Modulation of nutrient metabolism and homeostasis by the immune system

Sustainable land-based IMTA: Holistic management of finfish, mussel, and macroalgae interactions, emphasizing water quality and nutrient dynamics

This research aims to minimize the environmental impact and promote the sustainability of aquaculture by optimizing nutrient dynamics, improving water quality and enhancing species growth performance through a land-based Integrated Multi-Trophic Aquaculture (IMTA) system. The study focused on Black Sea trout (Salmo labrax), Mediterranean mussel (Mytilus galloprovincialis), and sea lettuce (Ulva lactuca), reared in interconnected tanks using Black Sea water over 90 days. The Black Sea trout more than doubled in size to 333.92 ± 6.60 g and significant improvements were observed in the specific growth rate (SGR) at 0.85% and the feed conversion ratio (FCR) at 1.38. The fish's proximate composition included 19.19% protein, 2.31% lipid, 70.35% moisture, and 1.34% ash, with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels at 6.06% and 13.50%, respectively. The macroalgae showed substantial growth, with a SGR of 0.34% and a weight gain of 310 ± 3.50 g. Additionally, it increased protein content by 13.41% and demonstrated significant nutrient removal efficiencies: 41.4% for nitrate, 66.7% for nitrite, and 90.8% for ammonia. EPA and DHA levels increased by 45% and 70%, reaching 4.66% and 2.19%, respectively. In contrast, the mussels experienced a weight loss, with a weight gain of -1.20 ± 0.00 g and an SGR of -0.20%. Initially, wild mussels had a composition of 77.56% moisture, 13.79% protein, 1.54% lipid, and 1.77% ash. The presence of mussels and macroalgae significantly improved water quality, notably reducing ammonia by 92.2%, nitrate by 44.6% and nitrite by 75%, benefiting the overall ecosystem. This study concludes that a land-based IMTA system enhances sustainable aquaculture by improving product quality and bioremediation, with macroalgae playing a crucial role in nutrient absorption and growth within the system.

A Meta-Analysis of the Effects of Dietary Yeast Mannan-Rich Fraction on Broiler Performance and the Implication for Greenhouse Gas Emissions from Chicken Production

Dietary supplementation of yeast-derived mannan-rich fraction (MRF) could improve the gastrointestinal health and production efficiency of broilers, and, consequently, lower the environmental impacts of chicken production. The objective of this meta-analysis was to quantify the retrospective effects of feeding MRF (Actigen®, Alltech Inc., Nicholasville, KY) on the production performance of broilers. The meta-analysis database included 27 studies and consisted of 66 comparisons of MRF-supplemented diets vs. basal (i.e., negative control) and antibiotic-supplemented (i.e., positive control) diets. A total of 34,596 broilers were involved in the comparisons and the average final age of the birds was 35 days. Additionally, the impact of feeding MRF on the carbon footprint (feed and total emission intensities) of chicken production was evaluated using the meta-analysis results of broiler performance (MRF vs. basal diets) to develop a scenario simulation that was analyzed by a life cycle assessment (LCA) model. A database of all trials (MRF vs. basal and antibiotic diets) indicated that feeding MRF increased (p < 0.01) average daily feed intake (ADFI; +3.7%), final body weight (FBW; +3.5%), and average daily gain (ADG; 4.1%) and improved (p < 0.01) feed conversion ratio (FCR; -1.7%) without affecting (p > 0.05) mortality. A subdatabase of MRF vs. basal diets indicated that dietary MRF increased ADFI (+4.5%), FBW (+4.7%), and ADG (+6.3%) and improved FCR (-2.2%) and mortality (-21.1%). For the subdatabase of MRF vs. antibiotic diets, both treatments exhibited equivalent effects (p > 0.05) on broiler performance parameters, suggesting that MRF could be an effective alternative to in-feed antibiotics. Subgroup analysis revealed that different study factors (year of study, breed/strain, production challenges, and MRF feeding duration) influenced the effect of dietary MRF on broiler performance. Simulated life cycle analysis (LCA) indicated that feeding MRF decreased feed and total emission intensities, on average, by -2.4% and -2.1%, respectively. In conclusion, these results demonstrate that dietary MRF is an effective nutritional solution for improving broiler performance, an effective alternative to in-feed antibiotic growth promoters, and reduces the environmental impact of poultry meat production.

Effects of a coccidiosis challenge on dietary methionine recommendations in broilers

Broilers are commonly exposed to coccidiosis infections, and the use of dietary strategies to reduce losses in growth performance has practical implications for the poultry industry. Methionine (Met) is typically the first limiting amino acid for broilers and is involved in metabolic and immunological pathways; however, literature is conflicting on how dietary Met requirements are affected by environmental stressors. Our objective was to assess how the Met requirement changes during coccidiosis based on results of growth performance, carcass traits, and health outcomes. Two trials were conducted using 780 male Ross 308 broiler chicks in floor pens randomly assigned to 1 of 12 experimental treatments. All birds received common starter (d 0-10) and finisher (d 24-35, Trial 2 only) diets, and only differed based on their assigned experimental grower diet (d 10-24). Trial 1 experimental grower diets ranged from 2.61 to 6.21 g/kg digestible Met. Trial 2 experimental grower diets were formulated to contain 15% below, at, or 15% above the Met requirement determined in Trial 1. Birds were exposed to a coccidiosis challenge on d 11, with blood and tissue collection (1 bird/pen) on d 18 and carcass processing on d 35 (2 birds/pen) in Trial 2. Data were analyzed using a 1- or 2-way ANOVA. A non-linear regression analysis was conducted in Trial 1 to determine the Met requirement of 4.32 g of digestible Met/kg of diet using BW gain. Coccidiosis infection reduced (P < 0.05) growth performance during the experimental grower and overall study periods in Trial 2. Increasing dietary Met from below requirement to meeting requirement during the grower period improved (P < 0.001) BW gain and feed conversion ratio (FCR), but this effect was only significant between treatments below and above the requirement for the overall study period. There was an interactive effect (P = 0.038) on FCR for the overall study period. These findings provide evidence that the Met requirement is likely increased during coccidiosis based on growth performance outcomes.

Garlic (Allium sativum) and mushroom (Agaricus bisporus) powder: Investigation of performance, immune organs and humoural and cellular immune response in broilers

BACKGROUND

Alternatives to antibiotics have been suggested by banning their use in the poultry industry. Garlic and mushroom are two important phytobiotic compounds in poultry nutrition.

OBJECTIVES

This study was conducted to evaluate the effects of supplementing diets with garlic and mushroom powder (MP) on growth performance, humoural and cellular immunity, and white blood cell counts of broiler chickens.

METHODS

Five hundred and seventy-six 1-day-old male broiler chickens (Ross 308) were assigned to 8 treatments with 6 replications (12 birds per replication) based on a completely randomized design in a factorial arrangement of 4 × 2 with 4 levels of garlic powder (GP; 0.00%, 0.50%, 1.00%, and 1.50%) and two levels of MP (0.00% and 1.00%).

RESULTS

No significant effects of GP and MP on the growth performance and cutaneous basophil hypersensitivity were observed (p > 0.05). According to the regression equation, with increasing levels of GP in the diets, the relative weight of the bursa of Fabricius and thymus increased (p < 0.05). The effect of increasing levels of GP on the Newcastle disease virus (NDV) titre was greater in the absence of MP (p < 0.05). With increasing levels of GP in the diets, the percentages of lymphocytes and heterophils to lymphocytes ratio increased and reduced, respectively (p < 0.05).

CONCLUSIONS

This experiment has revealed that increasing the level of GP improved the immune response of broilers without affecting performance. The effect of increasing the level of GP on the NDV titre was more significant in the absence of MP.

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.

Effect of rearing systems on immune status, stress parameters, intestinal morphology, and mortality in conventional and local chicken breeds

The majority of poultry meat used to be sourced from intensively housed birds. However, consumer preference has since demanded poultry producers develop more sustainable farming systems. Although free-range farming is considered beneficial for animal welfare, it is not as easy to standardize as an intensive system, which makes the choice of bird genotype appear crucial for alternative systems. In this study, we aimed to evaluate the effect of conventional and free-range rearing systems on the immune status, stress parameters, intestinal morphology and mortality in commercial hybrids (Ross 308) and local poultry strains, Bionda Piemontese (BP), Robusta Maculata (RM), BP x Sasso (BPxS), and RM x Sasso (RMxS). RNA was extracted from the jejunum and spleen to assess the mRNA expression of IL-2, IL-6, IL-10, IL-18, IL-1β, inducible nitric oxide synthase (iNOS), toll-like receptor (TLR)-4, and interferon gamma (IFN-γ). The heterophil:lymphocyte (H/L) ratio and intestinal histomorphometric evaluation were also calculated. We found that compared to the conventional system, the rearing system significantly affected the jejunum expression of IL-10, iNOS, IL-2, and IL-6, where these genes were upregulated in free-range system. A significant interaction between the rearing system and the genotype was also shown. More specifically, local breeds showed a significantly higher expression (P < 0.001) of IL-6 in the free-range system compared to the same genotypes in the conventional system. Moreover, IL-6 is constantly upregulated in local breeds within the free-range system compared to Ross hybrids. We also found significantly increased H/L and mortality rates in the latter, compared to the local breeds in the free-range reared system. The jejunum morphology also demonstrated a significantly higher villus height in BP and BPxS compared to the Ross hybrids. Overall, the results of our study confirm that the intense selection for growth in broiler chickens may have reduced their ability to react to the environmental stimuli related to free-range systems, resulting in a lower adaptability to a free-range environment, thus making them inappropriate for any farming system other than the conventional one. On the contrary, local chicken breeds are able to adapt and survive in the free-range system of rearing, and represent a genetic resource especially when adaptability to free-range conditions is required.

Chemical Composition and Functional Properties of Spray-Dried Animal Plasma and Its Contributions to Livestock and Pet Health: A Review

Spray-dried animal plasma (SDAP) is a functional ingredient derived from healthy animal blood, used as a nutritional additive in livestock and pet nutrition. SDAP is rich in macronutrients, micronutrients, and bioactive compounds such as immunoglobulins, albumin, growth factors, peptides, transferrin, and enzymes. This review focuses on the chemical composition of SDAP from porcine, bovine, and poultry sources, including protein quality and mineral profile. SDAP enhances performance and health in monogastric farm animals, aquaculture, and pets. It promotes growth rates and feed intake due to its high digestibility and superior amino acid profile compared to other protein sources. In pigs, SDAP's positive effects stem from tissue-specific actions in the gastrointestinal tract, impacting digestion, immunity, and barrier function. For poultry, SDAP shows promise as a substitute for antibiotic growth promoters, particularly in chick starter diets. SDAP contains functional proteins that regulate immune response, enhance intestinal health, and aid in stress conditions. It is also used as a binder in pet food, providing high protein content and other desirable properties. SDAP meets the dietary requirements of carnivorous pets, appealing to owners seeking animal-derived protein sources. Additionally, SDAP may help prevent cognitive impairment in senior dogs and cats.

Adapted tissue assay for the assessment of ileal granulocyte degranulation following in ovo inoculation with select bacteria or coccidial challenge in chickens

A previously described heterophil degranulation assay was adapted for use with ileal mucosal tissue via quantification of β-D-glucuronidase and assay end product 4-methylumbelliferone (4-MU). Three initial experiments evaluated the effect of in ovo inoculations of Citrobacter freundii (CF) or mixed lactic acid bacteria (LAB) on ileal granulocyte degranulation. Inoculations were administered on embryonic d18, body weights (BW) were recorded on day of hatch (DOH) and d10 to calculate body weight gain (BWG), and ileal mucosal scrapings were collected on DOH or d10 for the 4-MU assay. In all experiments, treatments were statistically analyzed relative to control groups. Treatments minimally affected BWG in all in ovo experiments (p > 0.05) relative to respective control groups. Similarly, ileal degranulation in in ovo treatments did not statistically differ (p > 0.05). Based on BWG, in ovo treatments may have induced low-level inflammation unable to elicit detectable changes via the 4-MU assay. Four subsequent experiments were conducted to evaluate effects of Eimeria maxima (EM) on ileal degranulation. Treatments included non-inoculated controls and low, medium, or high EM infection. Across all four experiments, final BW or BWG over the inoculation period were suppressed (p < 0.05) in EM groups relative to respective controls with the exception of EM-low (p = 0.094) and EM-medium (p = 0.096) in one trial. Ileal mucosal scrapings for the 4-MU assay were collected on day of peak lesions. Resulting values were reduced (p < 0.05) for EM treated birds in three experiments with the exception of EM-medium (p = 0.247). No differences were observed in one experiment (p = 0.351), which may have been attributed to a variation in strain of infecting Eimeria. Although refinement for low level inflammation is warranted, results indicate successful adaptation of the 4-MU assay for use with intestinal tissue during significant gastrointestinal inflammation.

Effects of Different Eimeria Inoculation Doses on Growth Performance, Daily Feed Intake, Gut Health, Gut Microbiota, Foot Pad Dermatitis, and Eimeria Gene Expression in Broilers Raised in Floor Pens for 35 Days

The study was conducted to investigate the effects of different Eimeria inoculation doses on the growth performance, gut ecosystem, and body composition of broilers in floor pens for 35 days. A total of 750 15-day-old broilers were allocated to five experimental groups with six replicate pens. The five experimental groups included unchallenged control (CON); Eimeria dose 1 (ED1): E. acervulina: 31,250/E. maxima: 6250/E. tenella: 6250; Eimeria dose 2 (ED2): E. acervulina: 62,500/E. maxima: 12,500/E. tenella: 12,500; Eimeria dose 3 (ED3): E. acervulina: 125,000/E. maxima: 25,000/E. tenella: 25,000; and Eimeria dose 4 (ED4): E. acervulina: 250,000/E. maxima: 50,000/E. tenella: 50,000. On D 21, BW were linearly reduced by increased Eimeria inoculation doses (p < 0.01). On D 35, the Eimeria challenge groups had significantly lower BW compared to the CON group. Increased Eimeria inoculation doses linearly decreased crude fat (CF) (p < 0.01) on D 21. Increased Eimeria inoculation doses tended to increase the relative abundance of the phylum Proteobacteria (p = 0.098) on D 21. On D 35, lean:fat was linearly reduced by increased Eimeria inoculation doses (p < 0.05). Eimeria infection negatively influenced growth performance and gut health in broilers in the acute phase, and the negative effects were prolonged to D 35 in floor pen conditions.

Behavior and Immune Response of Conventional and Slow-Growing Broilers to Salmonella Typhimurium

Fast growth rate in broiler chickens comes with welfare concerns and the contribution of growth rate to pathogen resistance and sickness behavior is relatively unknown. The objective of this study was to evaluate physiological and behavioral responses of conventional (CONV) and slow-growing (SG) male broilers challenged with Salmonella Typhimurium. CONV (n = 156) and SG (n = 156) chicks were raised in a pen with wood litter shavings until day 7 of age, when birds were transferred to 24 isolators (n = 11 chicks/isolator). On day 14 of age, half of the birds (n = 12 isolators) were challenged with S. Typhimurium (ST) and the other half (n = 12 isolators) received a control (C). On days 7, 13, 17, 21, and 24, body weight was recorded, and blood, jejunum and ileum sections were collected from 2 birds/isolator (n = 48 birds/sampling) to measure plasma IgA and IgG and intestinal histomorphology, respectively. On days 12, 16, 21, and 23, video was recorded to evaluate bird postures (sitting, standing, or locomoting) and behaviors (eating, drinking, preening, stretching, sham foraging, allopreening, and aggression). CONV birds were 70 g heavier (p = 0.03) on day 21 and 140 g heavier (p = 0.007) on day 24 than SG. On day 7, CONV jejunum villus height and crypt depth were 22 and 7 μm greater (p ≤ 0.001), respectively, than SG. On day 24, ST ileum villus height was 95 μm shorter (p = 0.009) than C. IgA increased after day 17 for all birds and at day 21, CONV IgA was greater (p = 0.01) than SG. Although SG IgG was 344 μg/ml greater (p = 0.05) than CONV on day 7, CONV IgG increased with age (p < 0.0001) to greater (p ≤ 0.03) concentrations than SG on day 21 and day 24 by 689 μg/ml and 1,474 μg/ml, respectively, while SG IgG remained at similar concentrations after day 13. Generally, a greater proportion of birds sham foraged as they aged (p < 0.0001). A greater proportion of CONV tended to sit (p = 0.09) and fewer locomoted (p < 0.0001) than SG as they aged. The results illustrate conventional and slow-growing broilers differ in their behavior, immunity, and response to Salmonella.

Role of diet-microbiota interactions in precision nutrition of the chicken: facts, gaps, and new concepts

In the intestine, host-derived factors are genetically hardwired and difficult to modulate. However, the intestinal microbiome is more plastic and can be readily modulated by dietary factors. Further, it is becoming more apparent that the microbiome can potentially impact poultry physiology by participating in digestion, the absorption of nutrients, shaping of the mucosal immune response, energy homeostasis, and the synthesis or modulation of several potential bioactive metabolites. These activities are dependent on the quantity and quality of the microbiota alongside its metabolic potential, which are dictated in large part by diet. Thus, diet-induced microbiota alterations may be harnessed to induce changes in host physiology, including disease development and progression. In this regard, the gut microbiome is malleable and renders the gut microbiome a candidate 'organ' for the possibility of precision nutrition to induce precision microbiomics-the use of the gut microbiome as a biomarker to predict responsiveness to specific dietary constituents to generate precision diets and interventions for optimal poultry performance and health. However, it is vital to identify the causal relationships and mechanisms by which dietary components and additives affect the gut microbiome which then ultimately influence avian physiology. Further, an improved understanding of the spatial and functional relationships between the different sections of the avian gut and their regional microbiota will provide a better understanding of the role of the diet in regulating the intestinal microbiome.

Supplemental feeding of northern bobwhite (

Northern bobwhites (Colinus virginianus) are a well known game bird that has been extensively studied and managed throughout its range for many decades. Despite this, bobwhites have continued a steady annual decline across the United States, irrespective of many well established conservation practices in place to mitigate this. Supplemental feeding is one such technique that is a widely used tool in bobwhite management, but the methods and results of the studies to investigate the effectiveness of this method are highly variable. The effectiveness of supplemental feeding practices is further hindered by the limited knowledge regarding the nutritional requirements of wild bobwhite because many of the guidelines that researchers follow are based on species of Galliformes that are primarily used for production. Here, we review supplemental feeding studies, nutritional requirements of bobwhite, and discuss future directions.

Effects of Clostridium butyricum, Sodium Butyrate, and Butyric Acid Glycerides on the Reproductive Performance, Egg Quality, Intestinal Health, and Offspring Performance of Yellow-Feathered Breeder Hens

Butyrate has been reported to promote the performance and growth of chickens. The specific roles and efficacy of different sources of butyrate remained unclear. Thus, the present study aimed to investigate and compare the effects of Clostridium butyricum (CB), sodium butyrate (SB), and butyric acid glycerides (tributyrin, BAG) on the reproductive performance, egg quality, intestinal health, and offspring performance of yellow-feathered breeder hens. A total of 300 Lingnan yellow-feathered breeder hens were assigned to five treatment groups: control (CL), 1×10⁸CFU/kg CB (CBL), 1×10⁹CFU/kg CB (CBH), 500mg/kg SB, and 300mg/kg BAG. Results showed that the laying performance and egg quality were increased by CBL, CBH, and BAG. Both CB treatments increased the hatchability of fertilized eggs. Maternal supplementation with both levels of CB significantly elevated the growth performance of offspring. Treatment with CBL, CBH, SB, and BAG all improved the oviduct-related variables and reduced the plasmal antioxidant variables. The CBH, CBL, and BAG treatments also improved the intestinal morphology to different degrees. Jejunal contents of IL-6 were decreased by CBH and BAG, while those of IL-4, IL-6, IL-1β, and IgY were decreased by SB. Transcripts of nutrient transporters in jejunal mucosa were also upregulated by CBH, CBL, and SB treatments and expression of Bcl-2-associated X protein was decreased by CBL, CBH, and BAG. In cecal contents, CBL increased the abundance of Firmicutes and Bacillus, while CBH decreased the abundance of Proteobacteria. Also, the co-occurrence networks of intestinal microbes were regulated by CBH and BAG. In conclusion, dietary inclusion of CB and BAG improved the reproductive parameters, egg quality, and intestinal morphology of breeders. CB also influenced the hatching performance of breeders and growth performance of the offspring, while SB improved the oviduct-related variables. These beneficial effects may result from the regulation of cytokines, nutrient transporters, apoptosis, and gut microbiota; high-level CB had more obvious impact. Further study is needed to explore and understand the correlation between the altered gut microbiota induced by butyrate and the performance, egg quality, intestinal health, and also offspring performance.

Adaptation of Livestock to New Diets Using Feed Components without Competition with Human Edible Protein Sources-A Review of the Possibilities and Recommendations

Simple Summary

Livestock feed contains components that can also be consumed by humans, which may become less available for livestock. Proteins are such components that may become less available for livestock feed. This review focuses on using alternative protein sources in feed. We may expect protein efficiency problems and we discuss how these could be solved using a combination of alternative protein sources and animal breeding. We make recommendations for the use and optimization of novel protein sources.

Abstract

Livestock feed encompasses both human edible and human inedible components. Human edible feed components may become less available for livestock. Especially for proteins, this calls for action. This review focuses on using alternative protein sources in feed and protein efficiency, the expected problems, and how these problems could be solved. Breeding for higher protein efficiency leading to less use of the protein sources may be one strategy. Replacing (part of) the human edible feed components with human inedible components may be another strategy, which could be combined with breeding for livestock that can efficiently digest novel protein feed sources. The potential use of novel protein sources is discussed. We discuss the present knowledge on novel protein sources, including the consequences for animal performance and production costs, and make recommendations for the use and optimization of novel protein sources (1) to improve our knowledge on the inclusion of human inedible protein into the diet of livestock, (2) because cooperation between animal breeders and nutritionists is needed to share knowledge and combine expertise, and (3) to investigate the effect of animal-specific digestibility of protein sources for selective breeding for each protein source and for precision feeding. Nutrigenetics and nutrigenomics will be important tools.

Field evaluation of feeding spray-dried plasma in the starter period on final performance and overall health of broilers

The effect of feeding spray-dried plasma (SDP) during the starter period was evaluated with a commercial broiler integrator on performance and overall health of broilers. The I See Inside (ISI) methodology assessing gut health in broilers was used as a tool to evaluate the impact of dietary interventions under commercial conditions. One hundred farms with approximately 1.1 million broilers were used at a Brazilian broiler integrator. Two groups of farms were fed either a control or an SDP diet containing 1% SDP, from 0 to 10 d of age. Diets were formulated to have similar nutritional density, containing zinc bacitracin and CuSO₄ from 0 to 28 d. After 10 d, both groups were fed common commercial diets. Performance data were analyzed together or by type of ventilation system: positive pressure or negative pressure. Birds were sent to market as they reached 3.05 kg; therefore, age at slaughter (AS) was evaluated as a dependent variable along with other performance measures. From the 100 farms in the trial, 35 (16 control and 19 SDP farms) were selected for the assessment of broilers health, biosecurity, and local management. For that, 6 broilers per farm at 14 ± 2 d of age were necropsied and ileum sampled for the ISI methodology evaluation. Biosecurity and management were also evaluated to obtain the influence of those parameters on animal health. SDP-fed birds demonstrated improved feed conversion ratio, reduced mortality, and 1 d less for AS (P < 0.05) vs. control group (P < 0.05) regardless of the type of ventilation. During necropsy, birds fed SDP showed lower coccidiosis and locomotor system lesions as the overall ISI score compared to controls. Histologic intestinal alterations were also lower in SDP-fed broilers (P < 0.05). In conclusion, feeding 1% SDP in the starter period to broilers resulted in improved performance and health under both good and bad management and biosecurity standards independent of the type of ventilation. Overall, there was good agreement between the ISI method and performance improvements observed.

Heat stress impairs egg production in commercial laying hens infected by fowl typhoid

Salmonella Gallinarum (SG) is an avian-restricted pathogen that causes fowl typhoid in poultry. Although it has been reported frequently over many decades in poultry flocks worldwide, the microorganism is more commonly associated with poultry in developing countries, particularly those with high ambient temperatures, where the acute form of the disease results in considerable economic losses. A more detailed investigation of environmental factors that affect the course of disease may assist in identifying effective prevention and control measures. Heat stress is known to impair the immunological response to a variety of pathogens and clearly may be an important contributory factor in the prevalence of disease in countries with warm or hot climates. Thus, the objective of the present study was to evaluate the effects of heat stress on chickens infected with SG. For this, light and semi-heavy commercial laying hens were distributed randomly within four groups as follows: infected and non-infected groups in rooms held at ambient temperature, and infected and non-infected groups under heat stress. Clinical signs, egg production, and mortality were recorded daily. Bacteriological counts in liver and spleen samples were estimated at 2, 5, 7, and 14 days post-infection. The results showed that both SG infection and heat stress had similar effects on egg production and a synergistic effect of the two stressors was observed. The data show an interaction between disease and heat stress which could point towards environmental and biosecurity approaches to resolving the possible 30% fall in production observed in such countries.

Comparative Studies of Inhibitory and Antioxidant Activities, and Organic Acids Compositions of Postbiotics Produced by Probiotic Lactiplantibacillus plantarum Strains Isolated From Malaysian Foods

Despite inflammation being a protective natural defense against imbalance stressors in the body, chronic inflammation could lead to the deterioration of immune response, low production, and poor performance in livestock as well as severe economic losses to the farmers. Postbiotics produced by Lactiplantibacillus plantarum has been reported recently to be a natural source of antioxidant, promoting growth performance, anti-inflammation, and immune responses. However, the effects of fermentation media on the compositions of L. plantarum postbiotic have not been reported elsewhere. Hence, a comparative study was conducted to compare the volatile compounds, organic acid composition, and antioxidant and antimicrobial activities of postbiotics produced by six strains of L. plantarum cultivated by using formulated media and the commercial de Man, Rogosa, and Sharpe (MRS) medium as a control. Postbiotics RG14, RI11, and UL4 produced by using formulated media exhibited higher inhibitory activity against Pediococcus acidilactici 446, Escherichia coli E-30, Salmonella enterica CS3, and vancomycin-resistant Enterococci except for Listeria monocytogenes LS55. As for the antioxidant activity, hydroxyl radical scavenging activity was enhanced in formulated media, whereas reducing power activity was the highest in postbiotic RI11. Three organic acids, namely, acetic acid, caproic acid, and lactic acid, were detected in the postbiotic produced by various L. plantarum strains. The concentration of acetic acid was influenced by the fermentation media, whereas caproic acid was detected as the highest in postbiotic RG11. Lactic acid was the predominant compound detected in all the postbiotics and had the significantly highest concentration in postbiotic RS5 when produced by using the MRS medium. Intermediary and pyrrole compounds were the other main compounds that were detected by using GC-MS. Positive correlations were found between organic acid production and inhibitory activity, as well as antioxidant activity exhibited by postbiotics. In conclusion, the compositions and functional characteristics of postbiotics produced by the six strains of L. plantarum were strain-dependent and affected greatly by the fermentation medium. The effects of postbiotic composition on the functional characteristics of postbiotics were elucidated in this study to warrant their applications as a promising beneficial natural growth promoter for the livestock industry.

Effect of vitamin E level and dietary zinc source on performance and intestinal health parameters in male broilers exposed to a temperature challenge in the finisher period

The objective of this study was to evaluate the interaction of zinc source (ZnSO₄ vs. zinc amino acid complex) and vitamin E level (50 IU vs. 100 IU) on performance and intestinal health of broilers exposed to a temperature challenge in the finisher period. A total of 1224 day old male Ross 308 broilers were randomly distributed among 4 dietary treatments (9 replicates per treatment). Dietary treatments were organized in a 2 × 2 factorial arrangement: two sources of zinc, 60 mg/kg of Zn as ZnSO₄ .7H₂ O or 60 mg/kg of Zn as zinc amino acid complexes (ZnAA) combined with two levels of vitamin E (50 or 100 IU/kg). Zinc and vitamin E were added to a wheat/rye-based diet that was designed to create a mild nutritional challenge. From day 28 until day 36 (finisher period), all birds were subjected to chronic cyclic high temperatures (32°C ± 2°C and RH 55-65% for 6 h daily). The combination of ZnAA and 50 IU/kg of vitamin E improved weight gain in the starter (day 0-10), finisher (day 28-36) and overall period (day 0-36) and feed conversion ratio in the starter (day 0-10) and finisher phase (day 28-36). Providing Zn as ZnAA significantly improved villus length and villus/crypt ratio in the starter, grower and finisher period and decreased infiltration of T-lymphocytes and ovotransferrin leakage in the finisher period. In conclusion, providing broilers with a diet supplemented with ZnAA and a vitamin E level of 50 IU/kg, resulted in better growth performance as compared to all other dietary treatments. Interestingly, under the conditions of this study, positive effects of ZnAA on performance did not occur when vitamin E was supplemented at 100 IU/kg in feed. Moreover, providing zinc as zinc amino acid complex improved intestinal health.

Differential expression of intestinal genes in necrotic enteritis challenged broiler chickens with 2 different Clostridium perfringens strains

The primary cause of necrotic enteritis (NE) disease in chickens is the NetB-positive Clostridium perfringens bacterium. Many factors are known to affect the severity of NE in the challenge models of broiler chickens, and one of these factors is the virulence of C. perfringens strain. This study was conducted to evaluate the effect of 2 pathogenic C. perfringens strains in a NE challenge model on gut health and mRNA expression of genes encoding apoptosis, tight junction, immunity, and nutrient transporters in broilers. Day-old Ross-308 male broilers (n = 468) were allocated in a 2 × 3 factorial arrangement of treatments with in-feed antibiotics (no or yes) and challenge (Non, C. perfringens strain NE18, and C. perfringens strain NE36) as the factors. The birds in the challenged groups were inoculated with Eimeria species on day 9 and with a fresh suspension of C. perfringens NE18 or NE36 on day 14 and 15. Sample collection was performed on 2 birds of each pen on day 16. Necrotic enteritis challenge, impaired feed conversion ratio during day 0 to 16 compared with the control group where the effect of the NE36 challenge was more severe than that with NE18 (P < 0.001). The mRNA expression of mucin-2, immunoglobulin-G, occludin (P < 0.001), and tight junction protein-1 (P < 0.05) genes were downregulated in both challenged groups compared with the nonchallenged counterparts. Antibiotic supplementation, on the other hand, increased weight gain, and feed intake in all challenged birds (P < 0.01), but upregulated mucin-5ac and alanine, serine, cysteine, and threonine transporter-1 (P < 0.05) only in the NE18 challenged birds. The challenge with NE36 significantly upregulated caspase-8 and claudin-1 (P < 0.001), but downregulated glucose transporter-2 (P < 0.001) compared with the NE18 challenge. These results suggest that NE challenge is detrimental to the performance of broilers through compromised intestinal health, and different C. perfringens strains can affect the severity of the disease through modulating the expression of intestinal genes encoding proteins responsible for apoptosis, gut integrity, immunity, mucus production, and nutrient transporters.

Effects of Laetiporus sulphureus-Fermented Wheat Bran on Growth Performance, Intestinal Microbiota and Digesta Characteristics in Broiler Chickens

Simple Summary

This study investigated the effects of a Laetiporussulphureus-fermented wheat bran (LS) supplementation on the microbiota and digesta characteristics of broiler chickens. Results showed that a 5% LS supplementation could potentially enhance the feed conversion ratio and European Broiler Index (EBI) of the broilers by elevating the family Lactobacillaceae and suppressing the phylum Proteobacteria’s population. This could also change the intestinal environments by elevating the ileal and cecal lactic acid concentrations as well as lowering the pH and ammonium nitrate, thereby potentially favoring the growth and health of the broilers.

Abstract

This study investigated the effects of a Laetiporus sulphureus-fermented wheat bran (LS) supplementation on the microbiota and digesta characteristics of broiler chickens. Two hundred and forty male broilers (Ross 308) were randomly allocated into three groups fed with a corn–soybean-based diet (control), and the control diet being replaced with 5% wheat bran (WB) and 5% LS, respectively. Each group had four replicates and 20 birds per pen. Metagenomics analysis results of the ileum microbiota showed that, at the family level, the 5% LS groups had over 40% higher Lactobacillaceae compared to the control group in a mean difference comparison. Heat maps showed that, at the phylum level, the population of Firmicutes was higher and Proteobacteria was lower in the ileum of 5% LS compared to the control group. Results of the stack column plots of the top ten OTUs at the family level showed that a 5% LS and 5% WB supplementation altered the broiler microbiota distribution by increasing the relative abundance of Lactobacillaceae. Cecal microbiota analysis showed that the 5% LS-supplemented group had approximately 5% and 3% higher Veillonellaceae and Lactobacillaceae, respectively. Stack column plots of the top ten OTUs indicated that the distribution of cecal bacteria in each group was not markedly different. Both the ileum and cecum digesta in the 5% LS supplementation group had a slight and not significant elevation on the total VFA, while the pH values and ammonia nitrogen were significantly lowered compared to the control and 5% WB groups (p < 0.05). In addition, the 5% LS supplementation group had a significantly higher lactic acid concentration in both the ileum and cecum compared to the control and 5% WB groups (p < 0.05). In conclusion, a 5% LS supplementation could potentially enhance the feed conversion ratio and European Broiler Index (EBI) of broilers by elevating the family Lactobacillaceae and suppressing the phylum Proteobacteria’s population, thus creating changed intestinal environments that may potentially favor the growth and health of the broilers.

Some aspects of the acute phase immune response to a lipopolysaccharide (LPS) challenge are mitigated by supplementation with a Saccharomyces cerevisiae fermentation product in weaned beef calves

This study was conducted to determine if feeding a Saccharomyces cerevisiae fermentation product (SCFP) to calves would alter the acute phase response to a lipopolysaccharide (LPS) challenge. Crossbred steer calves [n = 32; 274 ± 1.9 kg body weight (BW)] were randomly allotted to two treatment diets for 21 d: 1) control, fed RAMP (Cargill, Dalhart, TX) and 2) SCFP, fed the control ration supplemented with NaturSafe at 12 g/hd/d mixed into the TMR (NaturSafe, Diamond V, Cedar Rapids, IA). On day 22, steers were fitted with indwelling jugular catheters and rectal temperature monitoring devices and placed in individual bleeding stalls. On day 23, steers were challenged i.v. with 0.25 µg/kg BW LPS. Blood samples were collected at 0.5-h (serum) or 2-h (complete blood counts) intervals from -2 to 8 h and again at 24 h relative to the LPS challenge at 0 h. Sickness behavior scores (SBS) were recorded after the collection of each blood sample. Rectal temperatures were greater in SCFP steers from 6 to 11 h, at 13 h, from 15 to 20 h, and from 22 to 24 h following the LPS challenge compared to Control steers (treatment × time: P = 0.01). Additionally, SCFP-supplemented steers had reduced (P < 0.01) SBS compared to Control steers. Platelet concentrations remained greater in SCFP-supplemented steers compared to Control steers throughout the study (P = 0.05), while there was a tendency (P = 0.09) for SCFP steers to have greater white blood cells and eosinophils concentrations than Control steers. There was a treatment × time interaction for serum cortisol and glucose (P < 0.01). Specifically, cortisol was greater at 0.5 and 2 h postchallenge but was reduced at 3 h for SCFP steers compared to Control steers. Glucose was greater in SCFP steers at -0.5, 2, and 7.5 h compared to Control steers. Serum amyloid A was reduced in SCFP steers at 0.5 h, yet greater at 1 and 7.5 h postchallenge compared to Control steers (treatment × time: P < 0.01). Fibrinogen concentrations were greater (P < 0.01) in SCFP compared to Control steers. There was a treatment × time interaction (P < 0.01) for tumor necrosis factor-α (TNF-α) such that concentrations were reduced in SCFP steers from 1 to 2 h postchallenge compared to Control steers. Overall, these data suggest that supplementing calves with SCFP may have primed the innate immune response prior to the challenge, particularly platelets, which resulted in an attenuated sickness behavior and TNF-α response to LPS.

The Role of Arginine in Disease Prevention, Gut Microbiota Modulation, Growth Performance and the Immune System of Broiler Chicken – A Review

The effect of dietary arginine on disease prevention, immune system modulation, the gut micro-biota composition and growth of broiler chicken was reviewed. The main aim of poultry production is the maximization of profit at the least possible cost. This objective can mainly be achieved by ensuring that there is no interference in growth or disease outbreak and by feeding chicken with the best possible level of nutrients. With the ban on antibiotic growth promoters, attention is shifted towards other nutrition methods to prevent diseases and promote growth. More attention is therefore given to protein diets in animal nutrition due to their importance as essential part of active biological compounds in the body, assisting in the breakdown of body tissue and helping in the physiological processes of the animal. Arginine plays important function in serving as building blocks of proteins and polypeptides. It performs other roles during the regulation of important biochemical functions such as maintenance, growth, reproduction and immunity. Arginine cannot be synthesized by the body so it has to be supplemented in the diet. When arginine is supplemented above the recommended level, the gut mucosa is protected, immunosuppression is alleviated, diseases like necrotic enteritis, infectious bursal disease and coccidiosis in broiler chickens are prevented. There is an improvement in growth resulting from the increase in intestinal absorption, barrier function and microbiota composition.

Acetylation of Phenylalanine Hydroxylase and Tryptophan 2,3-Dioxygenase Alters Hepatic Aromatic Amino Acid Metabolism in Weaned Piglets

Weaning significantly alters hepatic aromatic amino acid (AAA) metabolism and physiological functions. However, less is known about the regulating mechanism of hepatic AAA metabolism after weaning. A total of 200 21-day-old piglets (Duroc × Landrace) were assigned randomly to the control group and the weaning group. In this study, weaning significantly decreased the concentration of phenylalanine, tryptophan, and tyrosine in piglet livers (p < 0.05). Additionally, through the detection of liver AAA metabolites and metabolic enzyme activity, it was observed that hepatic tryptophan catabolism was enhanced, while that of phenylalanine was weakened (p < 0.05). Intriguingly, acetyl-proteome profiling of liver from weaned piglets showed that weaning exacerbated the acetylation of phenylalanine hydroxylase (PAH) and the deacetylation of tryptophan 2,3-dioxygenase (TDO). Analysis of PAH and TDO acetylation in Chang liver cells showed that acetylation decreased the PAH activity, while deacetylation increased the TDO activity (p < 0.05). Furthermore, metabolites of AAAs and the acetylation statuses of PAH and TDO in primary hepatocytes from weaned piglets were consistent with the results in vivo. These findings indicated that weaning altered the PAH and TDO activity by affecting the acetylation state of the enzyme in piglets’’ livers. Lysine acetylation may be a potential regulatory mechanism for AAA metabolism in response to weaning.

A blend of fatty acids, organic acids, and phytochemicals induced changes in intestinal morphology and inflammatory gene expression in coccidiosis-vaccinated broiler chickens

Feed additives that promote gastrointestinal health may complement coccidiosis vaccination programs in antibiotic-free broiler production systems. This study examined the effects of a commercial feed additive blend (FA) on intestinal histomorphology and inflammatory biomarkers in vaccinated Ross 708 cockerels (N = 2,160). The study was a randomized complete block design (12 blocks) with 3 dietary treatments: CON (negative control), AGP (positive control: 55 ppm of bacitracin methylene disalicylate), and FA (1.5 kg/MT in starter; 1.0 kg/MT in grower; and 0.5 kg/MT in finisher). Birds were reared on re-used litter and fed a 3-phase feeding program (starter, 0 to 14 D; grower, 15 to 28 D; finisher, 29 to 36 D). One master batch of basal feed for each feeding phase was prepared and final experimental diets were manufactured by mixing the basal feed with the respective test ingredient prior to pelleting. Growth measurements, including pen body weight and feed intakes, and fresh fecal samples were taken throughout the study. On day 20, samples of intestinal tissue were collected from a subset of birds (n = 72, 1 block) for histomorphology and mRNA expression of tight junction and inflammatory genes. In the duodenum, the ratio of villi length to crypt depth was significantly lower in FA (and AGP) fed birds than those consuming the CON diet. Relative mRNA expressions of iNOS, IFN_Ɣ, and claudin-1 were upregulated in the jejunum of FA and AGP treatment groups compared to those in the CON group; the response in the FA was of lesser magnitude than AGP. Together, these results demonstrated that the FA treatment altered the microstructure of the duodenum and affected the expression of inflammatory genes in the jejunum. The timing of these changes coincided with peak oocyte shedding in feces and an observed reduction in feed efficiency in all dietary treatment groups.

Broilers fed a low protein diet supplemented with synthetic amino acids maintained growth performance and retained intestinal integrity while reducing nitrogen excretion when raised under poor sanitary conditions

The present study investigated the effects of supplementing a low protein (LP) diet supplemented with key essential amino acids (AA) to broilers on growth performance, intestinal tract function, blood metabolites, and nitrogen excretion when the animals were maintained under various sanitary conditions for 35 D after hatching. Three hundred eighty-four one-day-old male broilers (Ross 308) were randomly allotted to groups that received one of 6 dietary treatments in a 2 × 3 factorial arrangement (i.e., 2 environmental conditions and 3 dietary treatments) to give 8 replicates per treatment. Broilers were challenged with 2 environmental conditions (sanitary vs. poor sanitary). The dietary treatments were (1) high protein (HP) diet, (2) LP diet, and (3) LP diet with synthetic key essential AA (LPA): the LP diet was supplemented with synthetic AA up to the required levels for broilers. On day 14, birds consumed the LP diet impaired growth performance compared with those fed the HP diet, while the average daily weight gain-to-feed conversion ratio of birds fed the LPA diet improved to the level of birds fed the HP diet under poor sanitary conditions (P < 0.05). Broilers raised under poor sanitary conditions and fed the LP diet displayed higher (P < 0.05) zonula occludens (ZO-1) expression on day 14 than broilers fed either the HP or LPA diet. Under sanitary conditions, birds fed HP and LPA diets showed higher villus height and crypt depth compared with those of broilers fed the LP diet on day 35. Moreover, broilers raised in the poor sanitary environment had higher (P < 0.05) serum endotoxins than those raised in the sanitary environment. Broilers fed the LPA diet showed reduced (P < 0.05) nitrogen excretion on days 14 and 35 compared with those fed the LP and HP diets independent of the environment. In conclusion, the LPA diet did not impair growth performance under poor sanitary conditions for 14 D after hatch while resulting in lower nitrogen excretion in any environment conditions throughout the experiment.

Impact of Spray-Dried Plasma on Intestinal Health and Broiler Performance

Spray-dried plasma (SDP) is a functional ingredient commonly utilized in swine production and calf milk replacers to improve performance, feed efficiency, and health. The improvements noted with SDP in animal production are more pronounced under commercial production conditions compared to cleaner research settings. Multiple modes of action of SDP have been proposed, including either directly influencing the immune inflammatory response locally or systemically, and/or through the indirect modification of beneficial microbial populations. Spray-dried plasma included at various dietary levels and duration of feeding in broilers has been evaluated in different production and challenging conditions with beneficial effects on broiler performance, as noted in other animals. The purpose of this review is to discuss research related to the modes of action of SDP on immunomodulation and improved intestinal health and specifically discuss research conducted utilizing SDP in feed for poultry. Collectively, the data available indicates that SDP improves early intestinal health and supports an efficient immune system response both locally at the intestine and systemically, thereby benefiting growth, feed efficiency, and survival of broilers in conventional commercial production and under challenging conditions such as disease or environmental stressors.

Potential crosstalk of oxidative stress and immune response in poultry through phytochemicals - A review

Phytochemicals which exist in various plants and fungi are non-nutritive compounds that exert numerous beneficial bioactive actions for animals. In recent years following the restriction of antibiotics, phytochemicals have been regarded as a primal selection when dealing with the challenges during the producing process in the poultry industry. The selected fast-growing broiler breed was more fragile when confronting the stressors in their growing environments. The disruption of oxidative balance that impairs the production performance in birds may somehow be linked to the immune system since oxidative stress and inflammatory damage are multi-stage processes. This review firstly discusses the individual influence of oxidative stress and inflammation on the poultry industry. Next, studies related to the application of phytochemicals or botanical compounds with the significance of their antioxidant and immunomodulatory abilities are reviewed. Furthermore, we bring up nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and nuclear factor kappa B (NF-κB) for they are respectively the key transcription factors involved in oxidative stress and inflammation for elucidating the underlying signal transduction pathways. Finally, by the discussion about several reports using phytochemicals to regulate these transcription factors leading to the improvement of oxidative status, heme oxygenase-1 gene is found crucial for Nrf2-mediated NF-κB inhibition.

Performance effects of feed-borne Fusarium mycotoxins on broiler chickens: Influences of timing and duration of exposure

In commercial practice, broiler chickens may be exposed to Fusarium mycotoxins either during specific growth stages or throughout the entire production cycle. A 34-day feeding trial was conducted to identify sensitive periods for mycotoxin effects during the growth cycle of broiler chickens. A total of 420 newly-hatched Ross 308 male broilers were randomly assigned to 60 cages with 7 birds/cage. Sources of clean wheat (<0.5 mg/kg deoxynivalenol [DON]) and Fusarium-contaminated wheat (11.4 mg/kg DON) were used to formulate the starter diets (0.41 and 6.62 mg/kg DON) provided from 1 to 21 d of age and the grower diets (0.54 and 7.90 mg/kg DON) provided from 22 to 34 d. Control and DON diets were provided to broilers according to treatments (control, DON 1 to 14 d, DON 15 to 21 d, DON 22 to 34 d and DON 1 to 34 d). Birds were monitored daily for morbidity or mortality. Broiler growth performance (body weight, average daily gain, average daily feed intake and feed to gain ratio) was measured weekly. Segments of duodenum, jejunum and ileum were collected at 21 and 34 d and morphometric parameters (villus height, crypt depth, villus width, muscularis thickness and villi:crypt ratio) were measured. Birds fed the DON starter diet during the first 14 d did not exhibit any changes in growth performance; however, growth performance was suppressed in birds fed DON-contaminated diets during the grower period (22 to 34 d). At 34 d, birds that received the DON grower diet (DON 22 to 34 d and DON 1 to 34 d) were lighter (1,433 vs. 1,695 g) than birds fed the control diet. Feed to gain ratio was higher in birds fed the DON grower diet from 22 to 28 d (1.77 vs. 1.56) and 28 to 34 d (2.24 vs. 1.85) compared with corresponding controls. These results suggest that providing older broiler chicks (22 to 34 d) feed contaminated with Fusarium mycotoxins (specifically DON) may result in production losses. Histopathological analysis of the ileum region revealed that birds provided the DON diets throughout the entire trial (1 to 34 d) had shorter villi (506 vs. 680 μm) and shallower crypt (85 vs. 115 μm) than control birds. Taken together, these results indicate that DON-induced growth suppression may be a result of adverse effects on intestinal morphology during later growth phases of broilers.

Porcine epidemic diarrhea virus reduces feed efficiency in nursery pigs

Porcine epidemic diarrhea virus (PEDV) infects enterocytes and in nursery pigs, results in diarrhea, anorexia, and reduced performance. Therefore, the objective of this study was to determine how PEDV infection influenced growth performance and repartitioning of amino acids and energy in nursery pigs. A total of 32 barrows and gilts, approximately 1 wk post-wean (BW = 8.46 ± 0.50 kg), and naïve for PEDV were obtained, weighed, and allotted based on sex and BW to one of two treatments: 1) Control, PEDV naïve and 2) PEDV-inoculated (PEDV) with eight pens of two pigs each per treatment. On day post-inoculation (dpi) 0, PEDV pigs were inoculated via intragastric gavage with PEDV isolate (USA/Iowa/18984/2013). Pig and feeder weights were recorded at dpi −7, 0, 5, and 20 in order to calculate ADG, ADFI, and G:F. Eight pigs per treatment were euthanized on dpi 5 and 20, and tissues and blood were collected. At dpi 5, all PEDV pigs were PCR positive for PEDV in feces. Overall, PEDV pigs tended (P < 0.10) to increase ADFI, which resulted in reduced (P < 0.05) feed efficiency. At dpi 5, PEDV pigs had reduced (P < 0.05) villus height and increased (P < 0.05) stem cell proliferation in the jejunum compared with Control pigs. Pigs inoculated with PEDV had increased (P < 0.05) serum haptoglobin and increased insulin-to-glucose ratios compared with Control pigs at dpi 5. Markers of muscle proteolysis were not different (P > 0.05) between treatments within dpi; however, at dpi 5, 20S proteasome activity was increased (P < 0.05) in longissimus dorsi of PEDV pigs compared with Control pigs. Liver and jejunum gluconeogenic enzyme activities were not different (P > 0.05) between treatments within dpi. Overall, PEDV-inoculated pigs did recover the absorptive capacity that was reduced during PEDV infection by increasing proliferation of intestinal stem cells. However, the energy and nutrients needed to recover the epithelium may be originating from available luminal nutrients instead of muscle proteolysis and gluconeogenesis. This study provides insight into the effects of an enteric coronavirus on postabsorptive metabolism in nursery pigs.

The influence of oral copper-methionine on matrix metalloproteinase-2 gene expression and activation in right-sided heart failure induced by cold temperature: A broiler chicken perspective

This study was designed to investigate the expression, activation and activity of matrix metalloproteinase-2 (MMP-2) in the heart of broiler chickens reared in cold conditions and fed with copper-methionine supplement at different levels. The chickens (n=480) were randomly allotted to six treatments and four replicates. Treatments included two rearing temperatures (i.e. normal and cold temperatures) each combined with three levels of supplemental copper-methionine (i.e. 0, 100 and 200mg/kg). On d 38 and 45 of age, four broilers from each treatment were sacrificed and their hearts were stored at -80°C. Right-sided heart failure, as evident from abdominal and pericardial fluid accumulation, was observed in broilers under cold stress and not receiving supplemental copper. This clinical observation was confirmed at molecular level through increased MMP-2 expression, activation and activity in this group. Birds reared under normal temperature, however, were not involved in right-sided heart failure nor benefitted from copper-methionine supplementation. In contrast, gelatin zymography and real-time PCR demonstrated that dietary supplementation with copper-methionine decreased pro-MMP-2 and MMP-2 in the heart of chickens reared in cold conditions. However, gelatin reverse zymography did not show any difference between treatments in tissue inhibitor of metalloproteinase-2. Level of supplementation showed similar effects on parameters determined. It is concluded that dietary supplementation with copper-methionine reduced right-sided heart failure at clinical and molecular levels in cold-stressed chickens.

Heat Production and Energy Efficiency of Broilers Infected With Necrotic Enteritis

Necrotic enteritis (NE) in poultry is the most important bacterial disease in terms of economic losses. The present study was conducted to evaluate the effect of an experimental challenge with necrotic enteritis on respiration and heat production in birds pretreated with dietary acylated starch or antibiotics (AB) zinc bacitracin (50 mg/kg) plus salinomycin (60 mg/kg). In total, 48 1-day-old Ross 308 male broilers were assigned to floor pens until day 10. On day 11, birds were randomly placed into 16 calorimetric chambers with four replicates of three birds per treatment. Treatments were: control, AB, acetylated high-amylose maize starch (SA), or butyrylated high-amylose maize starch (SB). Birds were NE challenged by inoculation with 5000 sporulated oocysts each of Eimeria maxima and Eimeria acervulina and 2500 sporulated oocysts of Eimeria brunetti on day 9 and Clostridium perfringens (3.8 × 10(8) colony-forming units) on day 14. The results showed that heat production (HP), respiratory quotient (RQ), heat increment, weight gain (WG), feed intake (FI), and livability (LV) of birds fed control, SA, and SB diets were lower than birds fed AB at 19 and 42 hr postinoculation (P < 0.05). At 65 hr postchallenge, increased FI and WG of birds were observed, indicating recovery from NE. During the entire period, from day 14 to day 17, birds fed control, SA, and SB had lower WG, FI, HP, RQ, metabolizable energy intake (MEI), and metabolizable energy (P < 0.01) than those fed AB. The data demonstrate that Eimeria sp. and C. perfringens challenge reduces growth performance, HP, RQ, metabolizable energy, and MEI of birds fed control, SA, and SB but not AB diets.

Performance of pigs kept under different sanitary conditions affected by protein intake and amino acid supplementation

There is growing evidence that requirements for particular AA increase when pigs are kept under low sanitary conditions. The extent to which reduction in growth performance is related to these increased requirements is unclear. To evaluate this relationship, an experiment (2 × 2 × 2 factorial arrangement) was performed with 612 male pigs (9 per pen) kept under low sanitary conditions (LSC) or high sanitary conditions (HSC) and offered ad libitum access to either a normal CP concentration diet (NP; 17, 15, and 15% CP for the starter, grower, and finisher phase, respectively) or a low CP concentration diet (LP; 20% CP reduced relative to NP for each phase), each of which containing a basal AA profile (AA-B) or a supplemented AA profile (AA-S). The supplemented diet type contained 20% more Met, Thr, and Trp relative to Lys on an apparent ileal digestible basis compared with the basal diet type. Pigs were followed for a complete fattening period and slaughtered at a targeted pen weight of 110 kg. Haptoglobin concentrations in serum (0.92 g/L for LSC and 0.78 g/L for HSC) and IgG antibody titers against keyhole limpet hemocyanin (3.53 for LSC and 3.08 for HSC) collected in the starter, grower, and finisher phases and pleuritis scores at slaughter (0.51 for LSC and 0.20 for HSC) were greater for LSC pigs compared with HSC pigs ( ≤ 0.01), illustrating that sanitary conditions affected health conditions. The ADG and G:F were greater for HSC pigs compared with LSC pigs ( ≤ 0.01). The number of white blood cells (WBC) was higher in (AA-S)-fed pigs compared with (AA-B)-fed pigs when kept at LSC but not at HSC [SS (sanitary conditions) × AA interaction, = 0.04]. Pigs fed NP had a lower number of WBC compared with pigs fed LP ( = 0.02). The number of platelets in pigs fed AA-S diets was higher compared with pigs fed AA-B diets ( ≤ 0.01). A 20% reduction in dietary supplementation of Met, Thr, and Trp relative to Lys decreased G:F more in LSC pigs than in HSC pigs (interaction, = 0.03), illustrating that dietary requirements for these AA differ depending on sanitary conditions. This study, performed under practical conditions, shows that AA requirements are dependent on sanitary conditions. Furthermore, supplementation of diets with particular AA may improve performance, especially under poor hygienic conditions. Dietary protein concentration as well as Met, Thr, and Trp supplementation can modify immune status, which may influence resistance to subclinical and clinical diseases.

Effects of Graded Dietary L-arginine Supply on Organ Growth in Four Genetically Diverse Layer Lines during Rearing Period

Little information has been available about the influence of genetic background and dietary L-arginine (Arg) supply on organ growth of chickens. Therefore, the present study examined the effects of a graded ad libitum Arg supply providing 70, 100 and 200% of recommended Arg concentration on organ growth of female chickens from hatch to 18 weeks of age. The chickens derived from four layer lines of different phylogeny (white vs. brown) and laying performance (high vs. low). Based on residual feed and absolute body and organ weights recorded in six-week-intervals, feed consumption, changes of relative organ weights and allometric organ growth were compared between experimental groups. Surplus Arg caused higher feed intake than insufficient Arg (p<0.01) that induced growth depression in turn (p <0.05). During the entire trial chicken's heart, gizzard and liver decreased relatively to their body growth (p<0.001) and showed strong positive correlations among each other. On the contrary, proportions of pancreas and lymphoid organs increased until week 12 (p<0.001) and correlated positively among each other. Due to their opposite growth behaviour (p<0.001), internal organs were assigned to two separate groups. Furthermore, insufficient Arg induced larger proportions of bursa, gizzard and liver compared with a higher Arg supply (p<0.05). In contrast to less Arg containing diets, surplus Arg decreased relative spleen weights (p<0.01). The overall allometric evaluation of data indicated a precocious development of heart, liver, gizzard, pancreas and bursa independent of chicken's genetic and nutritional background. However, insufficient Arg retarded the maturation of spleen and thymus compared with an adequate Arg supply. In conclusion, the present results emphasised the essential function of Arg in layer performance, and indicated different sensitivities of internal organs rather to chicken's dietary Arg supply than to their genetic background.

AMPK and mTOR: sensors and regulators of immunometabolic changes during Salmonella infection in the chicken

Non-typhoidal Salmonella enterica induce an early pro-inflammatory response in chickens, but the response is short-lived, asymptomatic of clinical disease, results in a persistent colonization of the gastrointestinal (GI) tract, and can transmit infections to naïve hosts via fecal shedding of bacteria. The underlying mechanisms that facilitate this persistent colonization of the ceca of chickens by Salmonella are unknown. We have begun to concentrate on the convergence of metabolism and immune function as playing a major role in regulating the host responsiveness to infection. It is now recognized that the immune system monitors the metabolic state of tissues and responds by modulating metabolic function. The aim in this review is to summarize the literature that has defined a series of genotypic and phenotypic alterations in the regulatory host immune-metabolic signaling pathways in the local cecal microenvironment during the first 4 d following infection with Salmonella enterica serovar Enteritidis. Using chicken-specific kinomic immune-metabolism peptide arrays and quantitative real-time-PCR of cecal tissue during the early (4 to 48 h) and late stages (4 to 17 d) of a Salmonella infection in young broiler chickens, the local immunometabolic microenvironment has been ascertained. Distinct immune and metabolic pathways are altered between 2 to 4 d post-infection that dramatically changed the local immunometabolic environment. Thus, the tissue immunometabolic phenotype of the cecum plays a major role in the ability of the bacterium to establish a persistent cecal colonization. In general, our findings show that AMPK and mTOR are key players linking specific extracellular milieu and intracellular metabolism. Phenotypically, the early response (4 to 48 h) to Salmonella infection is pro-inflammatory, fueled by glycolysis and mTOR-mediated protein synthesis, whereas by the later phase (4 to 5 d), the local environment has undergone an immune-metabolic reprogramming to an anti-inflammatory state driven by AMPK-directed oxidative phosphorylation. Therefore, metabolism appears to provide a potential critical control point that can impact infection. Further understanding of metabolic control of immunity during infection should provide crucial information of the development of novel therapeutics based on metabolic modulators that enhance protection or inhibit infection.

A Comparison of the Chicken and Turkey Proteomes and Phosphoproteomes in the Development of Poultry-Specific Immuno-Metabolism Kinome Peptide Arrays

The use of species-specific peptide arrays for the study of animal kinomes has a proven track record of success. This technique has been used in a variety of species for the study of host–pathogen interactions and metabolism. Species-specific peptide arrays have been designed previously for use with chicken but a turkey array has never been attempted. In addition, arrays designed around individual cellular functions have been designed and utilized, but cross-function immuno-metabolic arrays have not been considered previously. Antecedent to designing separate chicken and turkey immuno-metabolic kinome peptide arrays, we show that while the chicken and turkey genomes are quite similar, the two species are much more distinct at the proteome and phosphoproteome levels. Despite a genome identity of approximately 90%, we observe that only 83% of chicken and turkey orthologous proteins display sequence matches between the two species. Further, less than 70% of kinase recognition target sequences are exact matches between chicken and turkey. Thus, our analysis shows that, at the proteome and kinome level, these two species must be considered separately in the design of novel peptide arrays. Our ultimate array design covers numerous immune and metabolic processes including innate and adaptive immunity, inflammatory responses, carbohydrate, protein, and fat metabolism, and response to hormones. We have shown the proteomic and phosphoproteomic diversity of chicken and turkey and have designed a valuable research tool for the study of immuno-metabolism within these two species.

Changes in the amount of lysine in protective proteins and immune cells after a systemic response to dead Escherichia coli: implications for the nutritional costs of immunity

The nutritional demands of the immune system may result in tradeoffs with competing processes such as growth and reproduction. The magnitude of the nutritional costs of immunity is largely unknown. Thus, we examine the lysine content of the systemic components of the immune system in adult male chickens (Gallus gallus domesticus) in a healthy condition (maintenance) and following a robust Escherichia coli-specific immune response. Lysine was used as a metric, because it is found both in leukocytes and in protective proteins. The dynamics of subsets of leukocytes were monitored in primary and secondary immune tissues (thymus, bone marrow, and spleen) that would be expected to be involved in the response following iv injection of E. coli. The systemic immune system at maintenance has the same lysine content as 332 average-sized feathers, 16% of an egg, or 5.4% of a pectoralis muscle from an adult chicken. During the acute-phase response to E. coli, the additional lysine needed would equal 355 feathers, 17% of an egg, or 5.5% of a pectoralis muscle. The acute-phase proteins accounted for the greatest proportion of lysine in the immune system at maintenance and the proportion increased substantially during an acute-phase response. Hypertrophy of the liver required more lysine than all of the leukocytes and protective proteins that were produced during the acute-phase response. Size of the liver and levels of protein during the acute phase returned to normal during the time when the adaptive response began to utilize significant quantities of lysine. The catabolism would release a surfeit of lysine to provision the anabolic processes of the adaptive response, thus making proliferation of lymphocytes and production of immunoglobulins very cheap.