An approach to alternative strategies to control avian coccidiosis and necrotic enteritis

Application of Bacillus amyloliquefaciens CECT 5940 influenced muscle satellite cells, PCNA and acute phase protein secretion in broilers

Despite the growing interest in the use of probiotics in broilers as feed additives, studies conducted to investigate the effect of probiotic administration on acute phase responses and the impact on muscle growth parameters in broilers are still limited. In this study, we investigated the effect of Bacillus amyloliquefaciens CECT 5940 on relative gene expression for growth factors involved in muscle development (insulin-like growth factors, myogenic factor 5, paired-box transcription factor), percentage of proliferating antigen cell nuclei in breast muscle, and secretion of acute phase proteins (serum amyloid A, haptoglobin, alpha1-acid glycoprotein) in the peripheral blood of broilers. Sixty one-day-old chicks from the experimental group were sprayed with a probiotic containing B. amyloliquefaciens at a dose of 1 × 1010 CFU/g directly after hatching and received the probiotic in drinking water (50 × 1010 CFU/1000 L) for 5 consecutive days of life. Sampling was performed on the 5th, 8th, and 12th day of life of the chicks. From the obtained results, we can conclude that B. amyloliquefaciens modulated the gene expression of selected growth parameters in the pectoral muscle, thereby increasing the number of satellite cells, however, their uptake into muscle fibers and thus increased hypertrophic growth was not proven at the time of the last sampling. At the same time, it demonstrated a potentiating effect on PCNA expression in chicken breast muscles in the early intensive growth phase of broiler chickens and modulated the production of acute phase proteins, which may contribute to improving adaptive processes during the growth and development of broilers.

Valine and isoleucine deficiency in necrotic enteritis challenge impact growth performance, intestinal health, and muscle growth in broilers

Necrotic enteritis (NE), an enteric disease caused by Clostridium perfringens, and antagonistic effects due to dietary branched-chain amino acid (BCAA) imbalance are key factors that negatively affect chicken growth. The current study was conducted to investigate the effects of valine and isoleucine deficiency in NE challenged broilers. A total of 336 seven-d-old male Cobb 500 were allotted to four treatments with six replicates. The four treatments were as follows: (1) non-challenged control (NC; leucine:lysine = 1.31, valine:lysine = 0.73, and isoleucine:lysine = 0.63), (2) NE-challenged group (NE), (3) NE-challenged with 85 % valine deficiency group (NE-VAL; valine:lysine = 0.62), and (4) NE-challenged with 85 % isoleucine deficiency group (NE-ILE; isoleucine:lysine = 0.54). E. maxima and C. perfringens were administered on d 14 and 18, respectively, and the experiment lasted until d 21. The NE-VAL group had the lowest growth performance measurements compared to the other groups (P < 0.001). All NE-challenged groups had significantly reduced overall growth performance measurements compared to the NC group (P < 0.001). The NE-ILE group showed no difference in any of the measurements compared to the NE group. On d 21, the NE group had significantly increased intestinal permeability, jejunal lesion scores, C. perfringens colony counts, and jejunal chemokine and cytokine gene expression levels, along with decreased intestinal morphology compared to the NC group (P < 0.05). The NE-VAL group had significantly decreased breast muscle yield, reduced lean and total tissue weight, and increased expression levels of mechanistic target of rapamycin pathway and BCAA catabolism-related genes compared to the NE group (P < 0.05). This may explain why the NE-VAL group had the lowest growth performance, as the two negative effects of NE infection and valine deficiency are separated. In conclusion, the negative effects of NE challenge and valine deficiency were independent; valine deficiency showed a similar response to that exhibited by high leucine levels, despite reduced feed intake caused by NE challenge.

A comparative evaluation of antibiotic and synbiotic supplementation on production performance and necrotic enteritis severity in broilers during an experimental necrotic enteritis challenge

The ban on antibiotics in the poultry diet resulted in re-emergence of several infectious diseases including necrotic enteritis (NE). These infectious diseases are leading to poor health and welfare as well as production and economic loss. Synbiotic could be a potential candidate to replace the antibiotics in poultry diet. Therefore, a 35-day study was conducted to compare the efficacy of synbiotic (PoultryStar®ME) and antibiotic (Stafac®50, Virginiamycin) supplementation during an experimentally induced necrotic enteritis infection. A total of 360 day-old chicks were randomly assigned to four treatment groups: Antibiotic, Challenge + Antibiotic, Synbiotic, and Challenge + Synbiotic, each with 6 replicates. The treatment groups referred as "Challenge + Antibiotic" and "Challenge + Synbiotic" were challenged, while their respective non-challenged treatment groups were "antibiotic" and "synbiotic". NE in birds was induced by gavaging 1 × 104 oocysts of Eimeria maxima on day 14 (D14) and 1 × 108 CFU/mL of Clostridium perfringens on D19, 20, and 21. Both synbiotic and antibiotic supplementation during the NE challenge did not improve BW gain, feed intake, and feed conversion ratio at the end of the experiment (D0-35). However, antibiotic supplementation reduced mortality during the week of the challenge (D14-21) (P < 0.001). At D21, both synbiotic and antibiotic supplementation during the NE challenge did not decrease the intestinal lesion score (P < 0.001) compared to their respective non-challenged treatment groups. At D21, synbiotic supplementation during the NE challenge did not decrease intestinal permeability (P = 0.04) compared to the synbiotic group. At D21, antibiotic supplementation during the NE challenge increased the CD4+:CD8+ T cells (P < 0.001) in the cecal tonsil. It can be concluded that synbiotic supplementation elicited an immune response, decreasing the inflammatory response in the intestine and ameliorating the NE infection. Therefore, synbiotic could be a potential alternative to replace antibiotics in the poultry industry, but their efficacy needs to be improved through blending additional probiotics and prebiotics, and further exploration is required.

Agglutination of Escherichia coli, Clostridium perfringens, and Salmonella enterica through competitive exclusion using potassium chloride with gum arabic

Bacterial infections causing necrotic enteritis and diarrhea pose a considerable economic loss to the animal industry. Using mannose oligosaccharides as competitive exclusion agents is an alternative method to antibiotic growth promoters; however, these materials are rapidly metabolized by gut microbiota, posing a challenge in sustaining their efficacy. The aim of this study was to identify an agglutination material that is effective against pathogens. Polysaccharides and salts were assessed using agglutination assays, microscopy, and zeta potential analysis. Gum arabic (GA) demonstrated strong agglutination against Escherichia coli and Salmonella enterica. Potassium chloride altered the cell form of Clostridium perfringens from rod-like to coccoid. When combined with GA, KCl effectively agglutinated all three bacterial species tested. Zeta potential analysis showed that agglutination resulted from bacteria, GA, and KCl interactions. Among various salts mixed with GA, KCl was found to strongly agglutinate C. perfringens upon its change into the coccoid form. Moreover, this combination has been shown to agglutinate mixtures of pathogens, such as C. perfringens and S. enterica. Thus, a combination of GA and KCl offers a potential solution to combat the pathogens associated with necrotic enteritis and diarrhea in animals.

Insights of early feeding regime supplemented with glutamine and various levels of omega-3 in broiler chickens: growth performance, muscle building, antioxidant capacity, intestinal barriers health and defense against mixed Eimeria spp infection

Early nutritional management approach greatly impacts broilers' performance and resistance against coccidiosis. The current study explored the impact of post-hatch feeding with a combination of glutamine (Glut) and different levels of omega-3 on broiler chickens' growth performance, muscle building, intestinal barrier, antioxidant ability and protection against avian coccidiosis. A total of six hundred Cobb 500 was divided into six groups: first group (fed basal diet and unchallenged (control) and challenged (negative control, NC) groups were fed a basal diet without additives, and the other groups were infected with Eimeria spp and supplemented with 1.5% Glut alone or with three different levels of omega-3 (0.25, 0.5 and 1%) during the starter period. Notable improvement in body weight gain was observed in the group which fed basal diet supplemented with glut and 1% omega 3 even after coccidia infection (increased by 25% compared challenged group) while feed conversion ratio was restored to control. Myogeneis was enhanced in the group supplemented with Glut and omega-3 (upregulation of myogenin, MyoD, mechanistic target of rapamycin kinase and insulin like growth factor-1 and downregulating of myostatin genes). Groups supplemented with Glut and higher levels of omega-3 highly expressed occluding, mucin-2, junctional Adhesion Molecule 2, b-defensin-1 and cathelicidins-2 genes. Group fed 1% Glut + omega-3 showed an increased total antioxidant capacity and glutathione peroxidase and super oxide dismutase enzymes activities with reduced levels of malondialdehyde, reactive oxygen species and H2O2. Post-infection, dietary Glut and 1% omega-3 increased intestinal interleukin-10 (IL) and secretory immunoglobulin-A and serum lysozyme, while decreased the elevated inflammatory mediators comprising interleukin IL-6, tumor necrosis factor-alpha, nitric oxide (NO) and inducible NO synthase. Fecal oocyst excretion and lesions score severity were lowered in the group fed 1% Glut and omega 3. Based on these findings, dietary Glut and omega-3 supplementation augmented restored overall broilers' performance after coccidial challenge.

Comparison of the effect of anticoccidial drug, probiotic, synbiotic, phytochemicals and vaccine in prevention and control of coccidiosis in broiler chickens challenged with Eimeria spp

The objective of this study was to investigate the effects of an anti-coccidiosis drug, vaccine, probiotic, symbiotic, and phytochemicals in the prevention and control of coccidia infection in broilers. A total of 525 one-day-old Ross 308 chicks were randomly allocated to 7 experimental diets with 5 replicates of 15 birds each in a completely randomized design. Experimental diets consisted of negative control (NC) without any additives and not challenged. The other 6 groups were challenged with mixed Eimeria and fed the basal diet with no additives (Positive Control, PC) or supplemented with Coxidine 100 (1 g / 1 kg), probiotic, synbiotic, Livacox T vaccine and phytobiotic additives based on the manufacturer's recommended dose. Body weight gain (WG), feed intake (FI) and feed conversion ratio (FCR) were recorded weekly. Oocysts per gram of excreta (OPG) were determined on d 25 to 33 and 42. One bird per cage was euthanized to analyze lesion score and jejunum and ileum inflammatory genes expression. Coccidial challenge reduced WG (P < 0.05) during 15 to 28 d and vaccine treatment was more effective in improving WG and FCR on d 29 to 42 and 1 to 42 (P < 0.05) than other treatments. Birds in the PC group had higher (P < 0.05) OPG than NC group for all days and the vaccine treatment resulted in the lowest rate of OPG compared to other treatments (P < 0.05) at 27, 28, 29, 30, 32, and 33 d of age and overall average. Relative mRNA levels of IFN-γ, IL-1β and IL-10 were significantly upregulated among treatments under coccidiosis challenge in jejunum and ileum except for IL-1β expression in the ileum. In conclusion, based on the results of this study the individual characteristics of feed additives for the prevention of coccidiosis can be different depending on the type and source of feed additives, duration, and amount used, levels of oocyst inoculation and Eimeria types.

Yeast cell wall supplementation affects the Salmonella enteretidis load in the ceca and ovaries of layer pullets

Salmonella enteretidis (SE) has a great propensity to translocate from the cecum into internal organs such as the spleen and liver. However, a major concern is the ability of SE to colonize the ovaries. This study aimed to evaluate the efficacy of cell walls from Saccharomyces cerevisiae to control the Salmonella load in the ceca and ovaries of commercial layer pullets. Ten-week-old layer pullets were divided into 2 groups: one group was fed a control diet with commercial feed without additives, and another group was fed the same diet supplemented with 0.5 kg/metric ton of yeast cell walls (YCWs). At 16 wk of age, the birds in both groups were challenged with 3.0 × 109 CFU/mL SE by oral gavage. The birds were euthanized on d 7 and 14 postchallenge to collect the ceca and ovaries for Salmonella load determination. The results demonstrated that there were no statistical differences in ovary SE infection rates. The trend in the prevalence of SE positivity in the ovaries was similar at 14 d, with 2.1% (YCW pullets) to 4.2% positive for the ovaries of the nontreated pullets. There was also no significant difference in the SE log10 MPN/gram between the YCW and the control groups. In the ceca, the high level of SE (3.0 × 109 cfu/pullet), which results in ovarian transmission, causes high intestinal tract inflammation. There was a significant difference in the prevalence of SE in the ceca at 7 d postchallenge but not at 14 d postchallenge. In conclusion, the reduction in Salmonella load observed in the ceca on d 7 in this study shows the potential of YCW supplementation for reducing Salmonella colonization in poultry.

Effect of Dietary Benzoic Acid and Oregano Essential Oil as a Substitute for an Anti-Coccidial Agent on Growth Performance and Physiological and Immunological Responses in Broiler Chickens Challenged with Eimeria Species

To overcome the antimicrobial residues in food, benzoic acid (BA) and oregano essential oil (OEO) are used in the broiler chicken industry. Independently, both exerted anticoccidial and antimicrobial actions and improved growth performance in broiler chickens. Their effect may be multiplied when they are used in combination. This present study was carried out to evaluate the efficacy of dietary BA and OEO alone or in combination as a substitute for a commercial coccidiostatic drug on growth performance and physiological and immunological responses in broiler chickens challenged with Eimeria species. A total of 252 unsexed 1-day-old broiler chicks were equally allotted to 36 pens, each pen containing seven chicks. The pens were randomly assigned to six treatments with six pens (replicates) for each treatment (n = 6)-(i) negative control, (ii) positive control, coccidia-challenged and non-treated, (iii) supplemented with salinomycin (an anti-coccidial drug) at 60 mg/kg of feed and coccidia-challenged, (iv) supplemented with BA at 500 mg/kg of feed and coccidia-challenged, (v) supplemented with OEOat 500 mg/kg of feed and coccidia-challenged (OEO), and (vi) supplemented with BA at 500 mg/kg of feed and OEO at 500 mg/kg of feed and coccidia-challenged (B&O). The liver enzymes and thyroxine and creatinine levels were not affected (p > 0.05) both in coccidia-challenged and supplemented chickens. The BA and OEO applied separately or in combination (B&O) significantly (p < 0.05) reduced gut pathogenic bacteria (Salmonella and Escherichia coli) and Eimeria spp., and concurrently enhanced (p > 0.05) the Lactobacillus population with better body weight gain, improved feed utilization, and superior hematological values. It also up-regulated (p > 0.05) the interferon-γ gene expression and down-regulated (p < 0.05) the interleukin-10 and Toll-like receptor-4 gene expression to protect the chickens from inflammatory reactions, which were not demonstrated in salinomycin-treated birds. The B&O supplementation increased (p < 0.05) the immune system by enhancing Eimeria-specific immunoglobulin Y titer and lymphocyte proliferation response. This study suggests that the combined application of OEO and BA can substitute for a commercial anti-coccidial agent (salinomycin) in controlling coccidiosis as well as improving growth performance, gut health, and immune responses in broiler chickens with a means of antimicrobial-resistant free food products.

The financial cost of coccidiosis in Algerian chicken production: a major challenge for the poultry sector

Coccidiosis, caused by parasites of the genus Eimeria, is a significant economic burden to the poultry industry. In this study, we conducted a comprehensive analysis to evaluate the financial losses associated with Eimeria infection in chickens in Algeria, relying on data provided by key stakeholders in the Algerian poultry industry to assess sub-clinical as well as clinical impact. We employed the updated 2020 version of a model established to estimate the cost of coccidiosis in chickens, taking into consideration specific cultural and technical aspects of poultry farming in Algeria. The findings predict economic losses due to coccidiosis in chickens of approximately £86.7 million in Algeria for the year 2022, representing £0.30 per chicken raised. The majority of the cost was attributed to morbidity (74.9%), emphasizing the substantial economic impact of reduced productivity including decreased bodyweight gain and increased feed conversion ratio. Costs associated with control measures made up 20.5% of the total calculated cost, with 4.6% of the cost related to mortality. These figures provide a clear indication of the scope and economic impact of Eimeria infection of chickens in Algeria, illustrating the impact of practices common across North Africa. They underscore the ongoing requirement for effective preventive and control measures to reduce these financial losses while improving productivity and welfare, ensuring the economic sustainability of the Algerian poultry industry.

Alternative to antimicrobial growth promoters in the diets of broilers challenged with subclinical necrotic enteritis

Necrotic enteritis (NE) is a disease of worldwide distribution, which affects young broilers and causes economic losses on a scale of 6 billion dollars per year. For decades, NE was controlled in poultry flocks by dietary administration of low doses of antimicrobial growth promoters (AGPs). However, an increase in NE incidence was noted after the AGP ban. This study aimed to compare the effect of an antibiotic (Enramycin) diet to a combination of sodium butyrate, hydrolyzed yeast, and zinc proteinate (ViligenTM) on broiler diets regarding performance, blood parameters, intestinal permeability, morphology and lesions, and carcass yield of broilers challenged with Eimeria spp. and Clostridium perfringens to simulate subclinical necrotic enteritis. A total of 1,150 one-day-old male broiler chickens with an initial average weight of 43.9 ± 0.65 g were allocated to 50 experimental pens. Animals were divided into 5 groups: Negative control (NC) without additives; Positive control (PC) with 0.12 g/ton of Enramycin (8%); V500, V1000, and V1500 with the addition of 500, 1.000, and 1.500 g/ton of Viligen, respectively. All animals were challenged by Eimeria spp. at 7 d of age and by C. perfringens at 17, 18, and 19 d for induction of subclinical NE. The broilers fed with all concentrations of Viligen showed similar performance, blood parameters, intestinal permeability, and carcass yield compared to PC broilers. However, NC broilers showed higher FCR compared to PC broilers from 1 to 33 d (1.42 vs. 1.39) (P = 0.048) and from 1 to 42 d (1.51 vs. 1.49) (P < 0.001). V1500 broilers had fewer intestinal lesions at 28 d when compared to the PC treatment (P < 0.05) and showed that higher Viligen inclusion resulted in lower intestinal damage. At 21 d, the V500 group showed higher intestinal morphology characteristics (VH:VD 4.9 vs. 3.5) compared to the PC treatment (P < 0.001). Thus, in this study, the dietary addition of Viligen to broilers challenged by an experimental model of subclinical NE resulted in lower intestinal damage and similar performance to that obtained by the addition of Enramycin.

Intestinal Microbiome Profiles in Broiler Chickens Raised with Different Probiotic Strains

The composition of the intestinal microbiota can influence the metabolism and overall functioning of avian organisms. Therefore, the objective of this study was to evaluate the effect of three different probiotics and an antibiotic on the microbiomes of 1.400 male Cobb® broiler raised for 42 days. The experiment was conducted with the following treatments: positive control diet (basal diet + antibiotic); negative control diet (basal diet without antibiotic and without probiotic); basal diet + Normal Avian Gut Flora (NAGF); basal diet + multiple colonizing strain probiotics (MCSPs); and basal diet + non-colonizing single strain probiotics (NCSSPs). The antibiotic (enramycin-antibiotic growth promoter) and probiotics were administered orally during all experiment (1 to 42 days), mixed with broiler feed. To determine the composition of the microbiota, five samples of ileal digesta were collected from 42-day-old chickens of each experimental group. The alpha and beta diversity of the ileal microbiota showed differences between the groups. MCSPs presented greater richness and uniformity compared to the positive control, negative control, and NCSSPs treatments, while the negative control exhibited greater homogeneity among samples than NCSSPs. MCSPs also showed a higher abundance of the genus Enterococcus. There were differences between the groups for low-abundance taxa (<0.5%), with NAGF showing higher levels of Delftia, Brevibacterium, and Bulleidia. In contrast, NCSSPs had a higher abundance of Ochrobactrum, Rhodoplanes, and Nitrospira. It was concluded that the treatments analyzed in this study induced modulations in the ileal microbiota of the chickens examined.

A comprehensive review of experimental models and induction protocols for avian necrotic enteritis over the past 2 decades

Necrotic enteritis (NE) is a severe gastrointestinal disease that poses a significant threat to the poultry industry. It leads to progressive damage to the small intestine, reduced performance, increased mortality rates, and substantial economic losses. With the removal of antimicrobial agents from chicken feed, there is an urgent need to find alternative approaches for NE control. Various approaches, including vaccination, prebiotics, probiotics, and plant-derived products, have been utilized to address NE in poultry management. To evaluate the efficacy of these preventive measures against NE, successful induction of NE is crucial to observe effects of these approaches in related studies. This study presents a comprehensive overview of the methods and approaches utilized for NE reproduction in related studies from 2004 to 2023. These considerations are the careful selection of a virulent Clostridium perfringens strain, preparation of challenge inoculum, choice of time and the route for challenge inoculum administration, and utilization of one or more predisposing factors to increase the rate of NE occurrence in birds under experiment. We also reviewed the different systems used for lesion scoring of NE-challenged birds. By gaining clarity on these fundamental parameters, researchers can make informed decisions regarding the selection of the most appropriate NE experimental design in their respective studies.

Combined Effect of Nigella sativa and Kefir on the Live Performance and Health of Broiler Chickens Affected by Necrotic Enteritis

Coccidiosis and necrotic enteritis (NE) are prevalent poultry ailments worldwide, leading to decreased live performance and elevated mortality rates without antibiotic usage. This study evaluated Nigella sativa (black cumin) seeds (BCS) and kefir as alternatives to antibiotics for broilers. An in vivo study over a 28-day period, using 384 Cobb 500 male broilers organized into six treatment groups as part of a completely randomized block experimental design was conducted. Each treatment group included eight replicates, with each replicate containing eight birds. The treatments included positive control, negative control, antibiotic control, 5% BCS in feed, 20% kefir in drinking water, and a combination of 5% BCS and 20% kefir. NE was induced in broilers by administering ~5000 oocysts of Eimeria maxima orally on day 14, followed by inoculation with about 108 CFU/mL of Clostridium perfringens (Cp) (strain Cp#4) on days 19, 20, and 21. Live performance metrics including feed intake, body weight gain, and feed conversion were assessed in broilers. Additionally, NE disease outcomes such as lesion scores, mortality rates, and Cp populations in cecum were determined during the study. The BCS, kefir, and the combination had no detrimental effect on broiler live performance. BCS-treated and combination groups had lower NE scores (p > 0.05) in comparison to the positive control and exhibited no significant difference (p > 0.05) from antibiotic control. Additionally, treatment groups and antibiotic control were not significantly different (p > 0.05) in mortality, whereas the BCS and kefir combination significantly reduced (p < 0.05) mortality to 14.1% compared to 31.3% for the positive control. C. perfringens vegetative cells significantly decreased (p < 0.05) in treatments with BCS, kefir, and their combination on days 22 and 28 compared to the positive control. On day 22, Cp sores were significantly lower (p < 0.05) for the kefir and combination treatments compared to the positive control. In conclusion, BCS and kefir successfully reduced C. perfringens infection and mortality without any detrimental impact on broiler live performance with the combined treatment being the most effective. These results suggest that BCS and kefir could serve as potential alternatives to antibiotics in managing NE.

Significance of successive feeding of sources of n-3 fatty acids to broiler breeders and their progeny on growth performance, intestinal lesion scores, lymphoid organs weight and plasma immunoglobulin A in broiler chickens challenged with Eimeria

The study examined the effects of successive feeding of sources of n-3 PUFA to broiler breeders (BB) and their progeny in broiler chickens challenged with Eimeria. The BB were fed: 1) control (CON), corn-soybean meal diet, 2) CON + 1 % microalgae (DMA), as a source of DHA and 3) CON + 2.50% co-extruded full fat flaxseed (FFF), as a source of ALA. Eggs were hatched at 34, 44, and 54 wk of age. Posthatch treatments (BB-progeny) were: CON-CON, DMA-CON, FFF-CON, DMA-DMA and FFF-FFF with diets formulated for starter (d 1-10) and grower/finisher (d 11-42) phases. All chicks were orally challenged with Eimeria (E. acervulina and E. maxima) on d 10. Relative to CON, DMA and FFF increased concentration of n-3 PUFA by ≥ 2-fold in hatching eggs and progeny diets. There were no (P > 0.05) interactions between treatment and BB age on d 0 to 10 growth. In general, BB age affected (P < 0.05) growth performance throughout the study. In the starter phase, successive exposure to DHA and ALA improved FCR over CON-CON (P < 0.01). The interaction between treatment and BB age in grower/finisher was such that DHA exposure to younger BB resulted in poor growth performance (P < 0.05) relative to exposure to older BB. In contrast, exposure to ALA had similar (P > 0.05) growth performance irrespective of BB age. Moreover, successive exposure to ALA resulted in higher BWG, breast weight and lower FCR compared to successive exposure to DHA (P < 0.05). There were no (P > 0.05) interactions between treatment and BB age on the intestinal lesion scores, lymphoid organ weights and concentration of plasma immunoglobulin A (IgA). Successive exposure to DHA resulted in higher (P = 0.006) jejunal lesion scores than CON-CON birds. The results showed that successive exposure of DHA and ALA improved FCR relative to non-exposed birds in the starter phase. However, responses in the grower/finisher phase depended on n-3 PUFA type, with birds on successive ALA exposure supporting better growth and breast yield than birds on successive DHA exposure.

Effect of dietary treatments on performance, oocysts shedding and lesion scores in broiler chickens experimentally challenged with Eimeria infection

Although anticoccidials effectively control coccidiosis, a needed reduction in the reliance on antimicrobials in animal production leads to the exploration of alternative compounds. The present study aimed to test five different dietary treatments to counteract the negative impact of coccidiosis on broiler chickens' health and performance. 1-day-old male Ross 308 broilers (n = 960) were randomly assigned to one of eight treatments, with six cages per treatment (20 birds/cage). To the diet of the broiler chickens of treatments (Trt) 1-5, a synbiotic was added from d0-10. From d10-28, birds of Trt1 and Trt2 were fed synbiotics, whereas birds of Trt3 were fed diets with glutamine, and birds of Trt4 and Trt5 were fed diets with a combination of β-glucans and betaine. From d28-35 onwards, birds of Trt1 were fed a diet with a synbiotic, whereas birds of Trt2-4 received diets with glutamine, and birds of Trt5 were fed a non-supplemented diet. Birds of the positive control group (PC; Trt6) were fed a standard diet supplemented with an anticoccidial (Decoquinate). The challenged negative control (NCchall; Trt7) and non-challenged negative control (NC) Trt8 were fed a standard diet without anticoccidial or other dietary treatment. At 7 days (d) of age, all birds were inoculated with 1 023, 115, and 512 sporulated oocysts of E. acervulina, E. maxima, and E. tenella, respectively, except for Trt8. Body weight gain (BWG), feed intake, and feed conversion ratio were assessed for each feeding phase (d0-10, d10-28 and d28-35) and overall experimental period (d0-35). Oocyst shedding, Eimeria lesion scores, cecal length, and relative weight were assessed at d13, d22, d28 and d35. Additionally, oocyst shedding was determined at d9 and d17. Litter quality was evaluated at d27 and d34, and footpad lesions at d34. During the starter (d0-10) and finisher (d28-35) periods, performance did not differ between the treatments. During the grower period (d10-28), Trt6 (PC) and Trt8 (NC) chickens had the highest BWG of all treatments (P < 0.001). Dietary treatment had no effect on litter quality and severity of footpad lesions. In the PC group (Trt6), low oocyst excretion and lesion scores were found. When comparing Trt1-5 with NCchall (Trt7), none of the treatments significantly reduced oocyst output or lesion scores. In conclusion, in this experiment, none of the dietary treatments performed similar or better compared to the PC group (Trt6) regarding performance or reducing Eimeria oocyst shedding or lesion scores.

Effects of phytase supplementation on broilers fed with calcium and phosphorus-reduced diets, challenged with Eimeria maxima and Eimeria acervulina: influence on growth performance, body composition, bone health, and intestinal integrity

An experiment was conducted to evaluate the effects of phytase in calcium (Ca) and available phosphorous (avP)-reduced diet on growth performance, body composition, bone health, and intestinal integrity of broilers challenged with Eimeria maxima and Eimeria acervulina. A total of 672 14-day-old male broilers were allocated to a 2 × 4 factorial arrangement with 6 replicates per treatment and 14 birds per replicate. Two factors were Eimeria challenge and 4 dietary treatments: 1) a positive control (PC; 0.84% Ca and 0.42% avP); 2) a negative control (NC; 0.74% Ca and 0.27% avP); 3) NC + 500 FTU/Kg of phytase (NC + 500PHY); and 4) NC + 1,500 FTU/Kg of phytase (NC + 1500PHY). On d 14, birds in the Eimeria-challenged groups received a solution containing 15,000 sporulated oocysts of E. maxima and 75,000 sporulated oocysts of E. acervulina via oral gavage. At 5 d postinoculation (DPI), the challenged birds showed a higher (P < 0.01) FITC-d level than the unchallenged birds. While the permeability of the NC group did not differ from the PC group, the phytase supplementation groups (NC + 500PHY and NC + 1500PHY) showed lower (P < 0.05) serum FITC-d levels compared to the NC group. Interaction effects (P < 0.05) of Eimeria challenge and dietary treatments on feed intake (FI), mucin-2 (MUC2) gene expression, bone ash concentration, and mineral apposition rate (MAR) were observed. On 0 to 6 and 0 to 9 DPI, Eimeria challenge decreased (P < 0.01) body weight (BW), body weight gain (BWG), FI, bone mineral density (BMD), bone mineral content (BMC), bone area, fat free bone weight (FFBW), bone ash weight, bone ash percentage and bone ash concentration; and it showed a higher FCR (P < 0.01) compared to the unchallenged group. The reduction Ca and avP in the diet (NC) did not exert adverse effects on all parameters in birds, and supplementing phytase at levels of 500 or 1,500 FTU/Kg improved body composition, bone mineralization, and intestinal permeability, with the higher dose of 1,500 FTU/Kg showing more pronounced enhancements. There was an observed increase in FI (P < 0.01) when phytase was supplemented at 1,500 FTU/Kg during 0 to 6 DPI. In conclusion, results from the current study suggest that dietary nutrients, such as Ca and avP, can be moderately reduced with the supplementation of phytase, particularly in birds infected with Eimeria spp., which has the potential to save feed cost without compromising growth performance, bone health, and intestinal integrity of broilers.

Coccidiosis in Egg-Laying Hens and Potential Nutritional Strategies to Modulate Performance, Gut Health, and Immune Response

Avian coccidiosis, despite advancements in management, nutrition, genetics, and immunology, still remains the most impactful disease, imposing substantial economic losses to the poultry industry. Coccidiosis may strike any avian species, and it may be mild to severe, depending on the pathogenicity of Eimeria spp. and the number of oocysts ingested by the bird. Unlike broilers, low emphasis has been given to laying hens. Coccidiosis in laying hens damages the gastrointestinal tract and causes physiological changes, including oxidative stress, immunosuppression, and inflammatory changes, leading to reduced feed intake and a drastic drop in egg production. Several countries around the world have large numbers of hens raised in cage-free/free-range facilities, and coccidiosis has already become one of the many problems that producers have to face in the future. However, limited research has been conducted on egg-laying hens, and our understanding of the physiological changes following coccidiosis in hens relies heavily on studies conducted on broilers. The aim of this review is to summarize the effect of coccidiosis in laying hens to an extent and correlate it with the physiological changes that occur in broilers following coccidiosis. Additionally, this review tries to explore the nutritional strategies successfully used in broilers to mitigate the negative effects of coccidiosis in improving the gut health and performance of broilers and if they can be used in laying hens.

Necrotic enteritis and antibiotic-free production of broiler chickens: Challenges in testing and using alternative products

The global trend towards raising broiler chickens without the use of in-feed antibiotics (IFAs) means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously provided. IFAs supported the productivity performance of chickens and played a key role in maintaining their health. Necrotic enteritis (NE) is an important disease of broilers that affects health, productivity, and welfare, and was previously well controlled by IFAs. However, with the reduction in IFA use, NE is resurgent in some countries. Vaccines and various feed additives, including pre-, pro-, and postbiotics, phytobiotics, fatty acids, and phage therapies have been introduced as alternative methods of NE control. While some of these feed additives have specific activity against the NE pathogen, Clostridium perfringens, most have the more general goal of reinforcing gut health. Extensive reviews of the effects of many of these feed additives on gut health have been published recently. Hence, rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative NE treatments and translating laboratory research to real world commercial production settings. The review is based on the author's particular experience, reading, thoughts, and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these issues. It is put forward to stimulate thinking and discussion on the issues covered.

Defining optimal dietary starch, oil, and amino acid inclusion levels for broilers experiencing a coccidiosis challenge

Alternative methods to alleviate coccidiosis in broilers are of interest to producers, including dietary strategies to minimize disruptions in growth rate and efficiency when faced with health challenges. Our objective was to determine optimal combinations of dietary starch, amino acids (AA), and oil to benefit productivity of broilers experiencing Eimeria-induced immune activation. Two trials were conducted using 1,536 male Ross 308 broiler chicks in floor pens randomly assigned to 1 of 17 experimental treatments. All birds received common starter (d 0-10) and finisher (d 24-35) diets, and only differed based on their assigned experimental grower diet (d 10-24). Trial 1 experimental grower diets ranged from 2,700 to 3,300 kcal/kg AME. Trial 2 included 10 experimental grower diets following a simplex lattice design consisting of 3 basal lots formulated to have the highest starch (45.4%), oil (10.2%), or AA density (120, 1.33% digestible Lys) and mixed in 4 equally spaced levels for each component (0, 0.33, 0.67, 1). These mixtures enabled varying densities of AA (80-120% of recommendation), starch:oil (4:1-20:1), and AME (2,940-3,450 kcal/kg). Bird and feeder weights were collected on d 0, 10, 24, and 35, and birds were exposed to an Eimeria challenge on d 11 or 12. In trial 2, excreta samples were collected for AME determination and carcasses were processed on d 36. Data were analyzed using ANOVA, t test, or regression. In Trial 1, BW gain and feed conversion were improved (P < 0.05) by increasing dietary AME. In Trial 2, birds receiving diets containing AA at 93 to 107% of recommendations and higher oil exhibited improved (P < 0.05) performance, but increased starch at the expense of oil reduced performance (P < 0.05). Relative breast and fat pad weights were not influenced by diet in Trial 2. We determined that broilers mildly challenged with Eimeria would exhibit highest BW gain when receiving diets containing 35.8% starch, 8.9% oil, and 101.3% of AA recommendations, which can be utilized by producers to maintain productivity under health-challenged conditions.

Effects of monensin sodium and live attenuated oocyst vaccine as coccidiosis management programs on productive performance, bone quality and mineral utilisation in broiler chickens

1. The following study was conducted to evaluate the influence of coccidiosis vaccine-induced metabolic stress on the utilisation of minerals in broilers. The starter, grower and finisher phase diets, including macro- and micro minerals at the recommended levels for the breed standards, were fed to chickens between 1 and 39 d of age.2. A total of 486, one-d-old male broilers were randomly distributed into three coccidiosis management programs (CMP) with six replications each. The CMP comprised: monensin sodium (MON), coccidiosis vaccine (VAC), not treated with MON or VAC (CNT).3. No significant differences between CMP were observed for body weight and weight gain among treatments. When compared to the CNT, the VAC program increased feed intake (P < 0.05) between d 1 to 13 and 14 to 26, while FCR worsened in the latter (P < 0.05) and the former (P = 0.05) periods.4. For birds in the MON and VAC programs, tibia bone length at d 13 and bone diameter at d 39 were both enhanced (P < 0.05). Meat yield characteristics were comparable among the CMP.5. Faeces of VAC birds had a lower (P < 0.05) dry matter and ash content than those in CNT program. CMP had no effect on serum or bone mineral concentrations at any point in time. For minerals, Mg, Na, and K faecal excretion was reduced (P < 0.01) as a result of the VAC program at d 13 with a trend at d 26.6. Compared to the CNT, the VAC program decreased the percentage ratio of drip loss (P = 0.08), water holding capacity (P < 0.01) and cooking loss (P < 0.01) in breast meat.7. Overall, the results showed that current broiler industry practices are capable of meeting the mineral needs of broilers vaccinated against coccidiosis.

Modulation of Broiler Intestinal Changes Induced by Clostridium perfringens and Deoxynivalenol through Probiotic, Paraprobiotic, and Postbiotic Supplementation

Deoxynivalenol (DON) is a predisposing factor for necrotic enteritis. This study aimed to investigate the effects of a DON and Clostridium perfringens (CP) challenge on the intestinal morphology, morphometry, oxidative stress, and immune response of broilers. Additionally, we evaluated the potential of a Lactobacillus spp. mixture as an approach to mitigate the damage induced by the challenge. One-day-old broiler chickens (n = 252) were divided into seven treatment groups: Control, DON, CP, CP + DON, VL (DON + CP + viable Lactobacillus spp. mixture), HIL (DON + CP + heat-inactivated Lactobacillus spp. mixture), and LCS (DON + CP + Lactobacillus spp. mixture culture supernatant). Macroscopic evaluation of the intestines revealed that the CP + DON group exhibited the highest lesion score, while the VL and HIL groups showed the lowest scores. Microscopically, all Lactobacillus spp. treatments mitigated the morphological changes induced by the challenge. DON increased levels of reactive oxygen species (ROS) in the jejunum, and CP increased ROS levels in the jejunum and ileum. Notably, the Lactobacillus spp. treatments did not improve the antioxidant defense against CP-induced oxidative stress. In summary, a Lactobacillus spp. mixture, whether used as a probiotic, paraprobiotic, or postbiotic, exerted a partially protective effect in mitigating most of the intestinal damage induced by DON and CP challenges.

Management and control of coccidiosis in poultry - A review

Poultry coccidiosis is an intestinal infection caused by an intracellular parasitic protozoan of the genus Eimeria. Coccidia-induced gastrointestinal inflammation results in large economic losses, hence finding methods to decrease its prevalence is critical for industry participants and academic researchers. It has been demonstrated that coccidiosis can be effectively controlled and managed by employing anticoccidial chemical compounds. However, as a result of their extensive use, anticoccidial drug resistance in Eimeria species has raised concerns. Phytochemical/herbal medicines (Artemisia annua, Bidens pilosa, and garlic) seem to be a promising strategy for preventing coccidiosis, in accordance with the "anticoccidial chemical-free" standards. The impact of herbal supplements on poultry coccidiosis is based on the reduction of oocyst output by preventing the proliferation and growth of Eimeria species in chicken gastrointestinal tissues and lowering intestinal permeability via increased epithelial turnover. This review provides a thorough up-to-date assessment of the state of the art and technologies in the prevention and treatment of coccidiosis in chickens, including the most used phytochemical medications, their mode of action, and the applicable legal framework in the European Union.

Anticoccidial effects of tannin-based herbal formulation (Artemisia annua, Quercus infectoria, and Allium sativum) against coccidiosis in broilers

Background

Avian coccidiosis is considered among the infectious disease of high cost in the poultry industry. Herbal extracts are safe and reliable substitute anticoccidial drugs for chemical feed additives as they do not sequel to drug resistance and tissue remnants.

Objective

The current study aimed to assess the anticoccidial effect of an herbal complex of 3 plants (Artemisia annua, Quercus infectoria, and Allium sativum) in broiler chickens compared to toltrazuril anticoccidial.

Methods

This experiment used one hundred twenty broiler chickens and divided them into four equally numbered groups. All the groups, except group (D), were experimentally infected with mixed Eimeria spp. (E. tenella, E. maxima, E. necatrix and E. brunetti) on day 14. Group (A) was treated with a herbal mixture, containing 75% Quercus infectoria with a minimum of 30% total tannin, 16% Artemisia annua with a minimum of 0.02% artemisinin, and 9% Allium sativum with a minimum of 0.4% total phenol contents. Group (B) was treated with toltrazuril. Group (C) did not have any treatment. Group (D) was healthy all the experiment period as a negative control group. During a 42-day breeding period, the study examined clinical signs, weight gains, feed conversion ratio, lesions scoring, casualties, and the number of oocysts in different bird groups.

Results

Group (D) showed the most significant weight gain, indicating the economic damage caused by coccidiosis. The best feed conversion ratio was observed in the unchallenged group, and coccidiosis negatively affected it in other groups. Clinical signs of dysentery, diarrhea, and lethargy were seen post-challenge but improved with treatment. Group (D) showed no losses; others had casualties and coccidiosis lesions. Lesion scores were lowest in the group (D), and the herbal mixture improved performance. The herbal mixture and toltrazuril reduced oocyst counts in feces earlier than the untreated group.

Conclusion

In conclusion, the anticoccidial activity of the mentioned herbal complex recommends its use as an alternative anticoccidial agent to chemotherapeutic drugs for controlling coccidiosis.

Eimeria maxima infection impacts the protein utilisation of broiler chicks from 14 to 28 days of age

In floor-raised broilers, coccidiosis is responsible for reducing the use of nutrients, mainly by impairing intestinal tissue function and activating the immune system. Understanding and quantifying how balanced dietary protein (BP) is used when birds are challenged will allow nutritionists to make decisions regarding challenged flocks. This study aimed to determine the effects of Eimeria maxima on broiler performance and body composition, and to calculate changes in the maintenance and efficiency of protein utilisation (Ep). A total of 2 400 male 14-day-old Cobb500 broiler chickens were randomly allotted to ten groups with six replications of 40 birds each, with a 5 × 2 factorial arrangement of treatments. Five levels of BP in reference to digestible lysine (3.6, 7.2, 10.8, 14.4, and 18.0 g/kg) were fed to unchallenged (NCH) and challenged (CH) broilers with 7 × 103E. maxima sporulated oocysts from 14 to 28 days of age. Performance and body deposition were measured using a comparative slaughter technique to compare BP maintenance requirements and Ep. ANOVA followed by a posthoc test was performed to compare the effects of BP levels, challenge, and their interactions. A monomolecular model describing the responses of NCH and CH broilers to BP intake, maintenance, and maximum protein deposition was compared. There were significant interactions between body weight gain and digestible lysine intake among the factors studied. Infection had a negative impact on all variables analysed, proving the efficacy of the challenge. The maintenance did not differ between the CH and NCH groups. Increased levels of dietary BP did not recover the maximum protein deposition in CH broilers. Eimeria maxima significantly reduced Ep by a factor of 0.09 times on Ep compared to the control group. The Eimeria maxima challenge was responsible to modify the use of BP altering the body composition and impairing broilers performance.

Efficacy of Bacillus subtilis to replace in-feed antibiotics of broiler chickens under necrotic enteritis-challenged experiments: a systematic review and meta-analysis

Necrotic enteritis (NE) and coccidiosis are among the most prevalent infectious diseases in broiler chickens, contributing to large profitability losses. Bacillus subtilis is a promising direct-fed probiotic to counter various pathogens infection in broiler chickens. Here, we performed a meta-analysis to investigate the effects of B. subtilis on broiler chickens performance. A total of 28 studies were selected according to a PRISMA checklist. Random-effect model and mixed-effect model of meta-analysis were fitted to estimate the overall effects of B. subtilis (BS) treatment compared to either the control group (CON) or NE-infected group (NEinf) as a baseline. Hedges' g effect size and its variance were used as estimators of standardized mean difference (SMD) calculation where the results were presented at a 95% confidence interval (95% CI) of the SMD. Overall, NEinf broiler chickens depressed (P < 0.01) body weight (BW), average daily gain (ADG), and feed intake, and elevated (P < 0.01) feed conversion ratio (FCR). Treatment with BS improved ADG and final BW of NEinf with no difference (P = 0.15) between BS and antibiotics (AB), indicating that they had comparable efficacy to treat NE in broiler chickens. BS supplemented to uninfected CON (BSS) improved (P < 0.01) final BW, ADG, and FCR. Compared to CON, BS, and AB failed to recover the FCR but these treatments decreased (P < 0.01) FCR when compared to the NEinf group with similar efficacy (P = 0.97). As expected, NEinf birds had a higher mortality rate (P < 0.01) and higher lesion score (P < 0.01) compared to CON, and treatment using AB and BS successfully decreased (P < 0.01) the mortality rate and lesion score. Compared to BS, AB was more effective to lower (P = 0.01) mortality rate, but comparable (P = 0.65) to minimize lesion score. To conclude, B. subtilis could be an effective natural additive to replace in-feed antibiotics in broiler chickens challenged with C. perfringens. However, the efficacy to reduce mortality rate was better with antibiotics treatment.

Effects of Eimeria maxima infection doses on growth performance and gut health in dual-infection model of necrotic enteritis in broiler chickens

The objective of this study was to investigate the effects of the different doses of Eimeria maxima (EM) oocysts on growth performance and intestinal health in broiler chickens challenged with a dual infection model of necrotic enteritis (NE) using EM and NetB+ Clostridium perfringens (CP). A total of 432 fourteen-d-old male Cobb 500 broiler chickens were divided into 6 groups with 6 replicates each. The six different groups were as follows: Control, non-challenged; T0+, challenged with CP at 1 × 109 colony forming unit; T5K+, T0+ + 5,000 EM oocysts; T10K+, T0+ + 10,000 EM oocysts; T20K+; T0+ + 20,000 EM oocysts; and T40K+; T0+ + 40,000 EM oocysts. The challenge groups were orally inoculated with EM strain 41A on d 14, followed by NetB+ CP strain Del-1 on 4 days post inoculation (dpi). Increasing EM oocysts decreased d 21 body weight, body weight gain, feed intake (linear and quadratic, p < 0.001), and feed efficiency (linear, p < 0.001) from 0 to 7 dpi. Increasing EM oocysts increased jejunal NE lesion score and intestinal permeability on 5, 6, and 7 dpi (linear, p < 0.05). On 7 dpi, increasing the infection doses of EM oocysts increased jejunal CP colony counts (linear, p < 0.05) and increased fecal EM oocyst output (linear and quadratic, p < 0.001). Furthermore, increasing the infection doses of EM oocysts decreased the villus height to crypt depth ratios and the goblet cell counts (linear, p < 0.05) on 6 dpi. Increasing EM oocysts downregulated the expression of MUC2, B0AT, B0,+AT, PepT1, GLUT2, AvBD3 and 9, LEAP2, and TLR4, while upregulating CLDN1, CATHL3, IL-1β, IFN-γ, TNFSF15, TNF-α, IL-10, and Gam56 and 82 on 6 dpi (linear, p < 0.05). Additionally, increasing EM oocysts decreased Pielou's evenness and Shannon's entropy (linear, p < 0.01). In conclusion, increasing the infection doses of EM significantly aggravated the severity of NE and exerted negative impact on intestinal health from 5 to 7 dpi.

Inclusion of Quillaja Saponin Clarity Q Manages Growth Performance, Immune Response, and Nutrient Transport of Broilers during Subclinical Necrotic Enteritis

Necrotic enteritis (NE) is an intestinal disease that results in poor performance, inefficient nutrient absorption, and has a devastating economic impact on poultry production. This study evaluated the effects of a saponin-based product (Clarity Q, CQ) during an NE challenge. A total of 1200 male chicks were randomly assigned to four dietary treatments (10 pens/treatment; 30 birds/pen): treatment 1 (NC), a non-medicated corn-soybean basal diet; treatment 2 (PC), NC + 50 g/metric ton (MT) of bacitracin methylene disalicylate (BMD); and treatments 3 (CQ15) and 4 (CQ30), NC + 15 and 30 g/MT, respectively. On the day (d) of placement, birds were challenged by a coccidia vaccine to induce NE. On d 8, 14, 28, and 42, performance parameters were measured. On d 8, three birds/pen were necropsied for NE lesions. On d 8 and d 14, jejunum samples from one bird/pen were collected for mRNA abundance of tight junction proteins and nutrient transporter genes. Data were analyzed in JMP (JMP Pro, 16), and significance (p ≤ 0.05) between treatments was identified by Fisher's least significant difference (LSD) test. Compared to PC and NC, CQ15 had higher average daily gain (ADG), while CQ30 had lower average daily feed intake (ADFI) and feed conversion ratio (FCR). NE lesions in the duodenum were lower in CQ15 compared to all other treatments. On d 8, mRNA abundance of CLDN1, CLDN5, AMPK, PepT2, GLUT2, and EAAT3 were significantly greater in CQ30 (p < 0.05) compared to both PC and NC. On d 14, mRNA abundance of ZO2 and PepT2 was significantly lower in PC when compared to all treatments, while that of ANXA1, JAM3, and GLUT5 was comparable to CQ15. In summary, adding Clarity Q to broiler diets has the potential to alleviate adverse effects caused by this enteric disease by improving performance, reducing intestinal lesions, and positively modulating the mRNA abundance of various tight junction proteins and key nutrient transporters during peak NE infection.

Dietary Palygorskite-Based Antibacterial Agent Supplementation as an Alternative to Antibiotics Improves Growth Performance, Blood Parameters, and Rumen Microbiota in Sheep

This research aimed to investigate the effects of a palygorskite-based antibacterial agent (PAA) as an alternative to antibiotics on growth performance, blood parameters, and rumen microbiota in sheep. A total of 120 sheep were randomly divided into five groups of six replicates with four sheep each. Sheep were fed a basal diet, an antibiotic diet supplemented with 500 g/t chlortetracycline (CTC), and a basal diet supplemented with 500, 1000, and 2000 g/t PAA for 80 d, respectively. Supplementation with 2000 g/t PAA and 500 g/t CTC increased the average daily gain (ADG) of sheep compared with the control group (p < 0.05). Diets supplemented with 2000 g/t PAA and 500 g/t CTC reduced (p < 0.05) the feed:gain ratio (F/G ratio) in the overall periods. Dietary supplementation with 1000 g/t PAA significantly increased albumin and total protein (p < 0.05). A significant positive correlation was found between growth hormone concentration and PAA supplementation (p < 0.05). In addition, compared to the control group, the CTC group had higher growth hormone concentration and lower lipopolysaccharide concentration (p < 0.05). No difference was observed between the five groups in terms of rumen fermentation characteristics (p > 0.05). At the phylum level, the relative abundance of Proteobacteria was lower in the PAA 2000 and CTC 500 groups than in the control and PAA 500 groups (p < 0.05). At the genus level, a significant decrease (p < 0.05) in the relative abundance of RuminococcaceaeUCG-010 was observed in the PAA 1000, PAA 2000, and CTC 500 groups compared with that in the control group. In addition, the relative abundance of Prevotella1 (p < 0.05) was higher in the PAA 2000 group than in the control group. These findings indicate that dietary supplementation with PAA has ameliorative effects on growth performance, blood parameters, and rumen microbiota, with an optimal dosage of 2000 g/t for sheep.

Pharmacological Effects of Grape Leaf Extract Reduce Eimeriosis-Induced Inflammation, Oxidative Status Change, and Goblet Cell Response in the Jejunum of Mice

Coccidiosis is a parasitic infection threatening poultry products globally. Parasite resistance to drugs is one of the barriers to Eimeria control. Natural products are one of the sources of compounds that prevent parasite infections. The current study was, therefore, conducted to evaluate the effect of Vitis vinifera leaf extract on anti-inflammatory response, oxidative status, and goblet cell response against Eimeria papillate infection in mice. Methanol was used as a solvent for phytochemicals. The mice were divided into six groups: The first group was the control. The second group was uninfected and treated with 200 mg/kg of extract to test toxicity, and the third, fourth, fifth, and sixth groups of mice received 1 × 10³ sporulated E. papillate oocysts. The third group received no treatment. The fourth and fifth groups were treated daily with 100 and 200 mg/kg of V. vinifera leaf extract, respectively, while the sixth group received 25 mg/kg of toltrazuril daily via gavage. On day 5 p.i., the animals were sacrificed, and jejunum samples were prepared for analyses of histological sections and oxidative stress. The phytochemical analysis using GC-MS of the extract showed the presence of 12 biologically active compounds. The most effective dose was 200 mg/kg, which significantly decreased the number of parasitic stages in the jejunal sections of the mice. The findings demonstrate that E. papillate infection in mice results in significant histopathological changes in the jejunum, including inflammation, epithelial vacuolation, villi loss, and a decrease in goblet cell density. When infected mice received treatment, the histological injury score within the infected jejunum tissue decreased by 63%, and the goblet cell quantity dramatically increased, approaching the control values. Finally, the extract ameliorated the changes in glutathione and malondialdehyde due to E. papillate infection. The extract was proven to have anti-inflammatory properties and reduce the number of oocysts. Overall, the findings show that V. vinifera leaf extract has significant anticoccidial effects in vivo.

Deconstruction of a multi-strain Bacillus-based probiotic used for poultry: an in vitro assessment of its individual components against C. perfringens

OBJECTIVE

Probiotics have been used in poultry production to improve the performance and health of chickens raised without antibiotics. The combination of different probiotic strains has been used with the hope of conferring multiple benefits to the host. However, the inclusion of several strains does not necessarily boost benefits. There is a lack of studies that compare the efficacy of multi-strain probiotics to their individual components. In this study, the effects of a Bacillus-based probiotic product mix containing B. coagulans, B. licheniformis, B. pumilus, and B. subtilis against Clostridium perfringens were tested in vitro using a co-culture method. The individual strains and different combinations of the strains used in the product were also tested against C. perfringens.

RESULTS

The probiotic product mix tested in this study did not show effects against C. perfringens (P = 0.499). When tested individually, the strain of B. subtilis was the most efficient strain to decrease C. perfringens concentrations (P ≤ 0.01), and the addition of other Bacillus species strains significantly decreased its efficacy against C. perfringens. We concluded that the probiotic mix of Bacillus strains used in this study (B. coagulans, B. licheniformis, B. pumilus and B subtilis) was not effective in decreasing C. perfringens concentrations in vitro. However, when deconstructing the probiotic, the strain of B. subtilis alone or combined with the strain of B. licheniformis were effective against C. perfringens. This suggests that the anticlostridial properties of the particular strains of Bacillus used in this study were negatively affected when combined with other Bacillus spp. strains.

In vivo anticoccidial activity and immune response of Moringa oleifera and Vernonia amygdalina leaves against Eimeria magna and Eimeria media in rabbits

Introduction

The aims of this study were to determine the immune response and the anticoccidial activity induced by Moringa oleifera and Vernonia amygdalina leaves in rabbits infected with Eimeria magna and Eimeria media.

Methods

Thirty-five-day-old rabbits, free from coccidia, were infested with 2.10³ oocysts of Eimeria magna and Eimeria media, then received the acetone extract of the leaves of Moringa oleifera and Vernonia amygdalina at different doses by oral gavage.

Results and discussion

The inhibition of the excretion of oocysts was evaluated by the McMaster technique and the levels of cytokines (IL-4 and IL-12) and immunoglobulin IgG were assayed by the ELISA method. The in vivo efficacy on E. magna and E. media oocysts was 95.43% and 96.53% for Moringa oleifera and Vernonia amygdalina at 1000 mg/kg bw against 98% for the positive control. Interestingly the plant extracts increased the production of interleukin (IL) and immunoglobulins (Ig) compared to controls. Plasma IL-4 levels (pg/ml) in rabbits were 128.94 and 131.38; those of IL-12 (pg/ml) were 395.55 and 426.56, and then for those of IgG (μg/ml) were 14.70 and 13.94 respectively with the acetone extracts of Moringa oleifera and Vernonia amygdalina on D14 PT at 1000 mg/kg bw. This study indicates that Moringa oleifera and Vernonia amygdalina can be used as an alternative to synthetic anticoccidials. These plants could be used to increase the resistance of the immune system of rabbits to infestations of Eimeria species in rabbit farms.

Impact of a Blend of Microencapsulated Organic Acids and Botanicals on the Microbiome of Commercial Broiler Breeders under Clinical Necrotic Enteritis

Previously, the supplementation of a microencapsulated blend of organic acids and botanicals improved the health and performance of broiler breeders under non-challenged conditions. This study aimed to determine if the microencapsulated blend impacted dysbiosis and necrotic enteritis (NE) in broiler breeders. Day-of-hatch chicks were assigned to non-challenge and challenge groups, provided a basal diet supplemented with 0 or 500 g/MT of the blend, and subjected to a laboratory model for NE. On d 20-21, jejunum/ileum content were collected for microbiome sequencing (n = 10; V4 region of 16S rRNA gene). The experiment was repeated (n = 3), and data were analyzed in QIIME2 and R. Alpha and beta diversity, core microbiome, and compositional differences were determined (significance at p ≤ 0.05; Q ≤ 0.05). There was no difference between richness and evenness of those fed diets containing 0 and 500 g/MT microencapsulated blend, but differences were seen between the non-challenged and challenged groups. Beta diversity of the 0 and 500 g/MT non-challenged groups differed, but no differences existed between the NE-challenged groups. The core microbiome of those fed 500 g/MT similarly consisted of Lactobacillus and Clostridiaceae. Furthermore, challenged birds fed diets containing 500 g/MT had a higher abundance of significantly different phyla, namely, Actinobacteriota, Bacteroidota, and Verrucomicrobiota, than the 0 g/MT challenged group. Dietary supplementation of a microencapsulated blend shifted the microbiome by supporting beneficial and core taxa.

Botanicals: A promising approach for controlling cecal coccidiosis in poultry

Avian species have long struggled with the problem of coccidiosis, a disease that affects various parts of the intestine, including the anterior gut, midgut, and hindgut. Among different types of coccidiosis, cecal coccidiosis is particularly dangerous to avian species. Chickens and turkeys are commercial flocks; thus, their parasites have remained critical due to their economic importance. High rates of mortality and morbidity are observed in both chickens and turkeys due to cecal coccidiosis. Coccidiostats and coccidiocidal chemicals have traditionally been added to feed and water to control coccidiosis. However, after the EU banned their use because of issues of resistance and public health, alternative methods are being explored. Vaccines are also being used, but their efficacy and cost-effectiveness remain as challenges. Researchers are attempting to find alternatives, and among the alternatives, botanicals are a promising choice. Botanicals contain multiple active compounds such as phenolics, saponins, terpenes, sulfur compounds, etc., which can kill sporozoites and oocysts and stop the replication of Eimeria. These botanicals are primarily used as anticoccidials due to their antioxidant and immunomodulatory activities. Because of the medicinal properties of botanicals, some commercial products have also been developed. However, further research is needed to confirm their pharmacological effects, mechanisms of action, and methods of concentrated preparation. In this review, an attempt has been made to summarize the plants that have the potential to act as anticoccidials and to explain the mode of action of different compounds found within them.

Bacillus subtilis Expressing Chicken NK-2 Peptide Enhances the Efficacy of EF-1α Vaccination in Eimeria maxima-Challenged Broiler Chickens

This study was conducted to investigate the synergistic effects of orally delivered B. subtilis-cNK-2 on vaccination with rEF-1α against E. maxima infection in broiler chickens. Chickens were assigned into the following five groups: control (CON, no Eimeria infection), non-immunized control (NC, PBS), component 1 (COM1, rEF-1α only), component 2 (COM2, rEF-1α plus B. subtilis empty vector), and component 3 (COM3, rEF-1α plus B. subtilis-NK-2). The first immunization was administered intramuscularly on day 4, and the second immunization was given one week later with the same concentration of components as the primary immunization. The immunization of B. subtilis spores (COM2 and COM3) was performed by oral administration given for 5 consecutive days a week later than the second immunization. On day 19, all the chickens except the CON group were orally challenged with E. maxima oocysts (1.0 × 10⁴/chicken). The results of the in vivo vaccination showed that all the chickens immunized with rEF-1α (COM1, COM2, and COM3) produced higher (p < 0.05) serum antibodies against EF-1α on 12 days post-E. maxima infection (dpi). The COM3 group showed a significantly (p < 0.05) higher average body weight gain (BWG) on 0-6, 6-9, and 0-12 dpi compared to those of the non-immunized chickens (NC). Immunization with rEF-1α alone (COM1) reduced the gut lesion score on 6 dpi and the fecal oocyst shedding on 9 dpi, whereas co-administration with B. subtilis spores (COM2 or COM3) led to further reduction in the lesion score. E. maxima infection increased the expression levels of IFN-γ and IL-17β in the jejunum, but these expressions were downregulated in the rEF-1α immunized (COM1) group and in the groups immunized with rEF-1α and orally treated with B. subtilis spores (COM2 or COM3) at 4 dpi. A reduced gene expression of occludin in the jejunum of the E. maxima-infected chickens on 4 dpi was upregulated following the immunization with COM2. Collectively, rEF-1α vaccination induced significant protection against E. maxima infection in the broiler chickens, and the efficacy of rEF-1α vaccination was further enhanced by co-administration with orally delivered B. subtilis spores expressing cNK-2.

Molecular Investigation of Eimeria Species in Broiler Farms in the Province of Vojvodina, Serbia

Coccidiosis is a significant poultry disease caused by the Eimeria species. This study aims to determine the prevalence of Eimeria spp. on broiler farms in Vojvodina, along with the identification of parasite species, and assess the implemented biosecurity measures. The study was conducted on 100 broiler chicken farms (28 small-sized; 34 medium-sized; 38 large-sized farms) from June 2018 to December 2021. One pooled sample of faeces was collected from three to six-week-old chickens from each farm, and assessment of biosecurity measures was carried out using a questionnaire. Using the PCR method, DNA of Eimeria was found in 59 samples (59%), while 41 samples (41%) were negative. Four species of Eimeria were identified, and their prevalence was the following: E. acervulina (37%), E. maxima (17%), E. mitis (25%) and E. tenella (48%). A significant difference (p < 0.05) was established in the number of oocysts in flocks from small-sized farms compared to medium-sized farms. It was found that regular implementation of disinfection, disinsection and deratisation measures, as well as all the biosecurity measures, can significantly reduce the occurrence of coccidiosis. These results will help to develop better strategies for the control and prevention of coccidiosis on farms.

Nutritional supplements for the control of avian coccidiosis

Coccidiosis is acclaimed as the most prevalent enteric parasitic ailment of poultry. It is caused by an apicomplexan protozoon of the genus Eimeria, which resides in chicken intestinal epithelium leading to intestinal damage. As a result, bloody droppings are there, feed efficiency is reduced, the growth rate is impaired, and egg production is temporarily decreased. Treatment and prevention of coccidiosis are primarily accomplished by inoculating live vaccines and administering anticoccidial drugs. Due to anticoccidials’ continuous and excessive use, the mounting issue is drug resistant Eimeria strains. The poultry industry has managed resistance-related issues by suggesting shuttle and rotation schemes. Furthermore, new drugs have also been developed and introduced, but it takes a long time and causes cost inflation in the poultry industry. Moreover, government disallows growth promoters and drugs at sub-therapeutic doses in poultry due to increased concerns about the drug residues in poultry products. These constraints have motivated scientists to work on alternative ways to control coccidiosis effectively, safely, and sustainably. Using nutritional supplements is a novel way to solve the constraints mentioned above. The intriguing aspects of using dietary supplements against coccidiosis are that they reduce the risk of drug-resistant pathogen strains, ensure healthy, nutritious poultry products, have less reliance on synthetic drugs, and are typically considered environmentally safe. Furthermore, they improve productivity, enhance nonspecific immunity, preventing oxidation of fats (acting as antioxidants) and inflammation (acting as an anti-inflammatory). The present manuscript focuses on the efficacy, possible mechanism of action, applications, and different facets of nutrition supplements (such as organic acids, minerals, vitamins, probiotics, essential oils, amino acids, dietary nucleotides, feed enzymes, and yeast derivatives) as feed additive for treating poultry coccidiosis.

Phenotypical Identification and Toxinotyping of Clostridium perfringens Isolates from Healthy and Enteric Disease-Affected Chickens

Clostridium perfringens is a ubiquitous spore-forming anaerobic pathogen that is frequently associated with enteric disease in chickens. Moreover, enterotoxin-producing C. perfringens has high zoonotic potential as well as serious public health concerns due to the emanation of food-borne intoxication. The present study was designed to isolate, identify, and toxinotype C. perfringens from both healthy and cases of necrotic or ulcerative enteritis chickens. A total of 110 samples were collected from July 2019 to February 2021. Among the samples, 38 (34.5%, 95% CI: 26.39-43.83) were positive for C. perfringens and were obtained from broiler 21 (33.3%, 95% CI: 22.91-45.67), Sonali 9 (34.6%, 95% CI: 19.31-53.88), and layer 8 (38%, 95% CI: 20.68-59.20). C. perfringens was highly prevalent (35.7%, 95% CI: 25.48-47.44) in enteritis chickens compared with healthy ones. In multiplex PCR toxinotyping, 34 (89.4%) isolates were identified as C. perfringens type A by the presence of the alpha toxin gene (cpa). Moreover, in addition to the cpa gene, 3 (14.3%, 95% CI: 4.14-35.48) broiler and 1 (11.1%, 95% CI: 0.01-45.67) Sonali isolates harbored the enterotoxin gene (cpe) and were classified as type F. However, none of the isolates carried genes encoding beta (cpb), epsilon (etx), iota (iap), or beta-2 (cpb2) toxins. Multivariable logistic regression analysis identified the following variables such as; "previously used litter materials" (OR 21.77, 95% CI 2.22-212.66, p ≤ 0.008); intestinal lesions, "presence of ulceration" (OR 30.01, 95% CI 3.02-297.91, p ≤ 0.004); "ballooned with gas" (OR 24.74, 95% CI 4.34-140.86, p ≤ 0.001) and "use of probiotics" (OR 5.24, 95% CI 0.74-36.75, p ≤ 0.095) act as risk factors for C. perfringens colonization in chicken gut. This is the first study of molecular toxinotyping of C. perfringens from healthy and enteric-diseased chickens in Bangladesh, which might have a potential food-borne zoonotic impact on human health.

Comparative efficacy of tannin-free grain sorghum varieties for the control of necrotic enteritis caused by Clostridium perfringens in broiler chickens

A 28-day battery cage study was conducted to test the efficacy of tannin-free grain sorghum varieties fed to Cobb 500 male broiler chickens (n = 512) and challenged with Eimeria maxima (EM) and Clostridium perfringens (CP). Birds were fed 1 of 8 treatments (corn, red/bronze, white/tan, or U.S. No. 2 sorghum) and were grouped by challenge method (challenged with EM/CP or unchallenged). On d 14, birds in the challenge group were orally inoculated with ∼5,000 oocysts of EM, and on d 19, 20, and 21, birds were given a broth culture of CP with ∼108 CFU/mL once daily. On d 21, three birds were scored for the degree/presence of necrotic enteritis (NE) lesions. Birds and feed were group weighed (d 0, 14, 21, and 28) to calculate average feed intake (FI), body weight gain (BWG), and adjusted feed conversion ratio (AdjFCR). Intestinal integrity was assessed through histological analysis of intestinal tissues, and change in transcriptome was determined using mRNA-sequencing on intestinal mucosa. Relative concentrations of secondary metabolites in grain sorghum were determined by LC-MS/MS analysis. Data were analyzed as a 2-way ANOVA with factors of treatment, challenge and their interaction. Regardless of challenge from 14 to 21 d, birds on the corn, white/tan, and U.S. No. 2 treatments were more efficient than those fed red/bronze treatment (P = 0.0026). From 14 to 28 d, BWG was significantly higher for the white/tan treatment (P = 0.024) compared to the red/bronze treatment. At 21 d, a significant interaction was observed for lesion score (P = 0.0001) in which, challenged birds fed red/bronze and white/tan treatments had reduced intestinal lesions compared to U.S. No. 2 and corn treatments. No differences among treatments were observed in jejunum morphology, but differential expression analysis showed an upregulation in defense response to bacteria and biotic stress in the challenged red/bronze treatment compared to the challenged corn. This study demonstrated improved gut health and minimal impact on growth and efficiency of broilers fed select grain sorghum varieties when challenged with EM/CP.

Production systems and important antimicrobial resistant-pathogenic bacteria in poultry: a review

Economic losses and market constraints caused by bacterial diseases such as colibacillosis due to avian pathogenic Escherichia coli and necrotic enteritis due to Clostridium perfringens remain major problems for poultry producers, despite substantial efforts in prevention and control. Antibiotics have been used not only for the treatment and prevention of such diseases, but also for growth promotion. Consequently, these practices have been linked to the selection and spread of antimicrobial resistant bacteria which constitute a significant global threat to humans, animals, and the environment. To break down the antimicrobial resistance (AMR), poultry producers are restricting the antimicrobial use (AMU) while adopting the antibiotic-free (ABF) and organic production practices to satisfy consumers' demands. However, it is not well understood how ABF and organic poultry production practices influence AMR profiles in the poultry gut microbiome. Various Gram-negative (Salmonella enterica serovars, Campylobacter jejuni/coli, E. coli) and Gram-positive (Enterococcus spp., Staphylococcus spp. and C. perfringens) bacteria harboring multiple AMR determinants have been reported in poultry including organically- and ABF-raised chickens. In this review, we discussed major poultry production systems (conventional, ABF and organic) and their impacts on AMR in some potential pathogenic Gram-negative and Gram-positive bacteria which could allow identifying issues and opportunities to develop efficient and safe production practices in controlling pathogens.

Probiotics as a Friendly Antibiotic Alternative: Assessment of Their Effects on the Health and Productive Performance of Poultry

Antibiotics have been used to maintain the overall health of poultry by increasing production efficiency, promoting growth, and improving intestinal function for more than 50 years. However, they have a number of side effects, such as antibiotic resistance, gut dysbiosis, destruction of beneficial bacteria, and the potential to spread diseases to humans. In order to address the aforementioned issues, a lot of effort is put into the development of antibiotic alternatives. One of them is the use of probiotics that can be added to the feed in order to increase poultry performance and avoid the aforementioned problems. Probiotics are live microorganisms consumed as feed additives or supplements. They function in the poultry gastrointestinal tract to benefit the host. Probiotics improve growth performance, bone health, meat and eggshell quality. The addition of probiotics to the diet also positively affects the immune response, intestinal microflora, and disease resistance. Careful selection of probiotic strains is of utmost importance. This review focuses on the significance of probiotics as a potential antibiotic-free alternative and the way in which they can be used as supplements in poultry feed for boosting production and safeguarding health.

The Importance of Dietary Antioxidants on Oxidative Stress, Meat and Milk Production, and Their Preservative Aspects in Farm Animals: Antioxidant Action, Animal Health, and Product Quality-Invited Review

The biological effects of oxidative stress and associated free radicals on farm animal performance, productivity, and product quality may be managed via dietary interventions-specifically, the provision of feeds, supplements, and forages rich in antioxidants. To optimize this approach, it is important first to understand the development of free radicals and their contributions to oxidative stress in tissue systems of farm animals or the human body. The interactions between prooxidants and antioxidants will impact redox homeostasis and, therefore, the well-being of farm animals. The impact of free radical formation on the oxidation of lipids, proteins, DNA, and biologically important macromolecules will likewise impact animal performance, meat and milk quality, nutritional value, and longevity. Dietary antioxidants, endogenous antioxidants, and metal-binding proteins contribute to the 'antioxidant defenses' that control free radical formation within the biological systems. Different bioactive compounds of varying antioxidant potential and bio-accessibility may be sourced from tailored feeding systems. Informed and successful provision of dietary antioxidants can help alleviate oxidative stress. However, knowledge pertaining to farm animals, their unique biological systems, and the applications of novel feeds, specialized forages, bioactive compounds, etc., must be established. This review summarized current research to direct future studies towards more effective controls for free radical formation/oxidative stress in farm animals so that productivity and quality of meat and milk can be optimized.

Antimicrobial monoglycerides for swine and poultry applications

The development of natural, broadly acting antimicrobial solutions to combat viral and bacterial pathogens is a high priority for the livestock industry. Herein, we cover the latest progress in utilizing lipid-based monoglycerides as feed additives to address some of the biggest challenges in animal agriculture. The current industry needs for effective antimicrobial strategies are introduced before discussing why medium-chain monoglycerides are a promising solution due to attractive molecular features and biological functions. We then critically analyze recent application examples in which case monoglycerides demonstrated superior activity to prevent feed transmission of viruses in swine and to mitigate bacterial infections in poultry along with gut microbiome modulation capabilities. Future innovation strategies are also suggested to expand the range of application possibilities and to enable new monoglyceride delivery options.

In Vitro Antiparasitic Activity of Propyl-Propane-Thiosulfinate (PTS) and Propyl-Propane-Thiosulfonate (PTSO) from Allium cepa against Eimeria acervulina Sporozoites

Among the alternatives to control avian coccidiosis, alliaceous extracts stand out due to their functional properties. Despite this, most of the references are focused just on garlic. In this study, we analyze the in vitro effects of propyl-propane thiosulfinate (PTS) and propyl-propane thiosulfonate (PTSO), two organosulfur compounds from onion, on MDBK cells infected with sporozoites of Eimeria acervulina. To this aim, two different experiments were performed. In the first experiment, sporozoites were previously incubated for 1 h at 1, 5 and 10 µg/mL of PTS or PTSO and added to MDBK cells. In the second experiment, MDBK cells were first incubated for 24 h at different concentrations of PTS or PTSO and then infected with E. acervulina sporozoites. Then, 24 h after inoculation, the presence of E. acervulina was quantified by qPCR. MDBK viability was measured at 72 h post-infection. Sporozoites incubated at 10 µg/mL of PTS and PTSO inhibited the capability to penetrate the cells up to 75.2% ± 6.44 and 71.7% ± 6.03, respectively. The incubation of MDBK with each compound resulted in a preventive effect against sporozoite invasion at 1 µg/mL of PTS and 1 and 10 µg/mL of PTSO. Cells incubated with PTSO obtained similar viability percentages to uninfected cells. These results suggest that the use of PTS and PTSO is a promising alternative to coccidiosis treatment, although further in vivo studies need to be performed.

Stimbiotic supplementation modulated intestinal inflammatory response and improved boilers performance in an experimentally-induced necrotic enteritis infection model

Background

Two experiments were conducted to establish an optimal NE challenge model and evaluate the efficacy of stimbiotic (STB) supplementation in necrotic enteritis (NE) challenged broilers. In Exp. 1, a total of 120 Arbor Acres (AA) broilers (45.0 ± 0.21 g) were randomly assigned to 6 treatments in a 3 × 2 factorial arrangement. Vaccine treatments included non-challenge (0), × 10 the recommended dose (× 10) or × 20 the recommended dose (× 20) by the manufacturer. Clostridium perfringens (CP) treatments were non-challenge (No) or 3 mL of 2.2 × 10⁷ CFU CP challenge (Yes). In Exp. 2, a total of 72 AA broilers (40.17 ± 0.27 g) were randomly assigned to 6 treatments in a 3 × 2 factorial arrangement. Dietary treatments included non-additive (CON), 100 mg/kg STB (STB) and 100 mg/kg STB on top of a typical commercial blend including an essential oil, probiotics, and enzyme (CB). Challenge treatments included non-NE challenge (No) and NE challenge (Yes) as established in Exp. 1.

Results

In Exp. 1, CP and vaccine challenge decreased (P < 0.05) body weight (BW), body weight gain (BWG) and feed intake (FI), and increased (P < 0.05) the number of broilers with diarrhea and intestinal lesions. The oral administration of × 20 recommended dose of vaccines coupled with 3 mL of 2.2 × 10⁷ CFU CP resulted in (P < 0.01) a significantly increased incidence of wet litter and intestinal lesions. Thus, this treatment was chosen as the challenge model for the successful inducement of NE in Exp. 2. In Exp. 2, the NE challenge negatively affected (P < 0.01) growth performance, ileal morphology, immunoglobulin contents in blood, caecal microbiota in the caecum, footpad dermatitis, intestinal lesion scores, tumour necrosis factor (TNF-α) and endotoxin in the serum compared with the non-NE challenged birds. The supplementation of STB and CB in diets enhanced (P < 0.05) growth performance, intestinal microbiota, and blood profiles by stimulating ileal morphology (VH and VH:CD) and propionate production in the cecum, and there were no differences in measured variables between STB and CB supplemented birds.

Conclusion

Overall, these results indicate that STB supplementation was able to reduce the inflammatory response and improve the performance of NE challenged birds, and the supplementation of STB alone was as effective as a typical commercial blend containing a number of other additives.

The effect of spices Coriandrum sativum L., Trigonella foenum-graecum L., Pimpinella anisum L., and their combinations on growth performance, carcass trait, and hematobiochemical parameters in broiler chicken

Background and Aim:

The incorporation of herbs and species has been shown to enrich the food with antioxidants and bioactive antimicrobial compounds, thereby preserving the safety and productivity of broiler chicken production. This study aimed to determine the effects of three phytogenic feed additives (PHT) on certain zootechnical and hematobiochemical parameters in broiler chickens. Coriandrum sativum L. (coriander), Pimpinella anisum L. (green anise), and Trigonella foenum-graecum L. (fenugreek) were used to formulate the PHT.

Materials and Methods:

A total of 360 1-day-old Cobb broilers for 42 days were randomly assigned to four dietary treatment groups: A control group (CTLG) and three groups fed a basal diet supplemented with 3% of coriander (PHT1G), 3% of a combination 50% coriander-50% fenugreek (PHT2G), and finally, 3% of a combination 50% coriander-50% green anise (PHT3G), respectively, and each experimental group included three repetitions of 30 birds. Zootechnical parameters, carcass productivity, and hematobiochemical properties were measured.

Results:

The birds in the PHT3G had the greatest body weight and organ weight (p < 0.05). However, the weight of abdominal fat remained unchanged. The same group of broilers had a significantly (p < 0.05) higher lymphocyte level of 120.10³/μL, followed by the PHT2G, which had 80.10³/μL. The levels of monocytes in the PHT2G and PHT3G were 66.10³/μL and 60.10³/μL, respectively. Regarding granulocytes, we observed 200.10³/μL in the PHT2 group and 102.10³/μL in the PHT3G. There was a statistically significant difference (p < 0.05) between the uric acid levels of the PHT1G, PHT2G, and PHT3G, with 50.4 mg/L, 59.84 mg/L, and 47.29 mg/L, respectively. All experimental groups had significantly lower uric acid concentrations than the control group (84.36 mg/L).

Conclusion:

The use of phytogenic feed additives may positively affect both weight gain and hematobiochemical parameters in broiler chicken, particularly the levels of various white blood cell subtypes and the uric acid rate.

Evaluation of Predisposing Factors of Necrotic Enteritis in Experimentally Challenged Broiler Chickens

Simple Summary

The ban of antibiotic growth promoters in animal feed increased the number of cases of necrotic enteritis (NE) in broilers, greatly affecting the poultry industry. The induction of experimental NE faces challenges, as it is a multifactorial disease and the pathogenesis is not fully understood, hampering the development of in vivo studies for disease control and prevention strategies. The literature reports several protocols using different factors to assist in NE induction. This study assessed predisposing factors, such as immunosuppression, infection or both, by Eimeria spp. in broilers (n = 99) fed a wheat-based diet and challenged with three different strains of Clostridium perfringens (CP). Under microscopy, Eimeria spp. had a negative effect on intestinal morphometry and favored the increase of intraepithelial lymphocytes. However, the macroscopic analysis did not show which factor was more effective in potentiating the lesions, suggesting a synergistic effect between the strain of CP used and the predisposing factors. Therefore, each experimental protocol should first be evaluated for the association of the CP strain with the predisposing factors.

Abstract

Clostridium perfringens is the etiological agent of NE, a disease that greatly affects the poultry industry. Experiments on the induction of NE are difficult to carry out, as it is a multifactorial disease, and thus different predisposing factors have been used. This study evaluated the effect of the Gumboro disease vaccine virus vaccine (IBDV-vac) associated or not with infection by Eimeria spp. in broilers, as a predisposing factor for NE. Broilers (n = 99) were divided into groups (11) challenged with IBDV-vac, Eimeria spp. CP type G (CP13, CP14 and CP03) or both. The macroscopic evaluation revealed that the highest average (3.45) of injury occurred for the CP13 + IBDV-vac group. The microscopic analysis showed that Eimeria spp. increased the population of intraepithelial lymphocytes and reduced the villus/crypt ratio in duodenum and jejunum when associated with CP13 or CP14. There was a synergistic effect between the CP strain used and the predisposing factors; nevertheless, it was not clear which was the most effective predisposing factor to potentiate the lesions, suggesting that the association of the strain with the factors should first be evaluated for each experimental protocol.

The influence of nutrition on intestinal disease with emphasis on coccidiosis

Ever since the poultry industry began to intensify early last century, coccidiosis has been a significant problem with which it has had to contend. Losses due to mortality and morbidity can be significant and before the advent of control agents there were several practices, some of which were nutritional, which were implemented to limit these losses. The development of coccidiostats reduced these problems considerably and as a result some of the more extreme intervention measures were no longer necessary. Modern day interpretation of what may have been happening with some of these early interventions provide interesting insights into what may be possible today should cocciodiostats be removed. More recent research has also indicated that the diet has a significant influence on the ability of poultry to resist and resolve an infection through direct and indirect effects on the pathogen, the immune system and on the litter. This paper reviews the role of dietary ingredients and nutrients on the pathogen to establish and the host to resist such an infection. There is clearly no panacea, but the combination of a few practices may reduce the overall challenge experienced by the poultry producer.

Standardized ileal digestibility of amino acids in broiler chickens fed single or mixture of feed ingredients-based diets with or without Eimeria challenge

The effect of Eimeria challenge on standardized ileal digestibility (SID) of amino acids (AA) in major poultry feed ingredients fed to broiler chickens was determined. A total of 840 male 9-day-old Ross 708 chicks were placed in 84 cages (10 birds/cage) and allocated to either a nitrogen-free diet (NFD) or one of the 6 test diets based on a single or mixture of feed ingredients as the sole source of AA (n = 12). Test diets were: 1) corn, 2) wheat, 3) soybean meal (SBM), 4) pork meal (PM), 5) corn, SBM, and PM (CSP), and 6) wheat, SBM, and PM (WSP). On d 10, birds in 6 cages/diet were orally gavaged with 1 mL of E. acervulina and E. maxima mixture and the other 6 cages with sham. On d 15, birds were bled for plasma AA and necropsied for intestinal lesion scores and ileal digesta samples. Challenge decreased (P < 0.05) plasma concentration of Arg, His, Thr, Asp, Gln, and Tyr and increased concentration of Lys, Ile, Leu, and Val. There was a diet by challenge interaction (P < 0.05) on intestinal lesion scores with birds fed mixed diets exhibiting more severe lesions than birds fed single ingredient diets. Diet by challenge interacted (P < 0.05) on ileal total endogenous flow (ITEF) of AA except for Arg, Met, Ala, Asp, and Cys, such that challenged birds fed the mixed, particularly WSP, had higher ITEF of AA compared to single ingredients birds. Diet and challenge interaction (P < 0.05) was observed for SID of Arg, Thr, Val, Glu, and Gly. Challenge decreased (P < 0.05) SID of most AA except for Met, Asp, and Cys with the largest impact seen on Lys, His, Ser, and Thr. With exception of Arg, Thr, Asp, and Cys, birds fed mixed diets had higher (P < 0.05) SID values compared to birds fed single ingredients. In conclusion, Eimeria reduced plasma availability and ileal digestibility of most AA. However, challenge interaction with diet composition on SID of some AA warrants further investigations.

Gastrointestinal Microbiota and Their Manipulation for Improved Growth and Performance in Chickens

The gut of warm-blooded animals is colonized by microbes possibly constituting at least 100 times more genetic material of microbial cells than that of the somatic cells of the host. These microbes have a profound effect on several physiological functions ranging from energy metabolism to the immune response of the host, particularly those associated with the gut immune system. The gut of a newly hatched chick is typically sterile but is rapidly colonized by microbes in the environment, undergoing cycles of development. Several factors such as diet, region of the gastrointestinal tract, housing, environment, and genetics can influence the microbial composition of an individual bird and can confer a distinctive microbiome signature to the individual bird. The microbial composition can be modified by the supplementation of probiotics, prebiotics, or synbiotics. Supplementing these additives can prevent dysbiosis caused by stress factors such as infection, heat stress, and toxins that cause dysbiosis. The mechanism of action and beneficial effects of probiotics vary depending on the strains used. However, it is difficult to establish a relationship between the gut microbiome and host health and productivity due to high variability between flocks due to environmental, nutritional, and host factors. This review compiles information on the gut microbiota, dysbiosis, and additives such as probiotics, postbiotics, prebiotics, and synbiotics, which are capable of modifying gut microbiota and elaborates on the interaction of these additives with chicken gut commensals, immune system, and their consequent effects on health and productivity. Factors to be considered and the unexplored potential of genetic engineering of poultry probiotics in addressing public health concerns and zoonosis associated with the poultry industry are discussed.