Impacts of tea tree or lemongrass essential oils supplementation on growth, immunity, carcass traits, and blood biochemical parameters of broilers reared under different stocking densities

Consequences of dietary cinnamon and ginger oils supplementation on blood biochemical parameters, oxidative status, and tissue histomorphology of growing Japanese quails

The present study aimed to investigate the impact of various concentrations of ginger and cinnamon oils as antibiotic substitutes on some blood biochemical parameters, antioxidant capacity, and histopathological profile of the liver and gut of growing Japanese. A total of 900 Japanese quails were randomly allotted into 6 treatment groups. Each group had 5 replicates (30 chicks each). The first group received a basal diet and served as the control, while the second received a basal diet plus 0.5 g of colistin antibiotic/kg diet. The third and fourth groups were supplemented with 0.5 mL and 1.0 mL of ginger oil (GO)/kg diet, respectively. While the fifth and sixth groups received basal diet with 0.5 and 1.0 mL of cinnamon oil (CO)/kg diet, respectively. Results showed that adding herbal oils significantly (P < 0.05) decreased the aspartate aminotransferase (AST) and urea levels compared to control and colistin groups. Various levels of GO and CO significantly (P < 0.05) reduced cholesterol levels compared to control birds. Compared to the control and antibiotic groups, Japanese quails supplemented with various levels of herbal oils (GO and CO) had more extraordinarily significant (P < 0.05) values for total antioxidant capacity (TAC), superoxide dismutase (SOD), glutathione peroxidase (GPX), and glutathione reductase (GSR). Regarding histopathologic examination, the jejunum displayed a nearly empty lumen, a few fusions, and mild goblet cell metaplasia. On the other hand, the duodenum looked tall and had a few fusions of villi and remnants of removal in its lumina. It could be concluded that cinnamon and GO improved birds' blood biochemical parameters, electorate oxidative stress, and enhanced intestinal and hepatic histology of the treated quails. Also, the levels of 0.5 mL CO and 0.5 mL GO may be an acceptable substitute for antibiotics (colistin) in the diets of growing Japanese quail.

Evaluation of the Interaction between Gum Arabic Addition and Stocking Density on Growth Performance, Carcass Characteristics, and General Health Parameters of Broiler Chickens

The present study aims to investigate the interaction between the addition of gum arabic as a prebiotic and various stocking densities on performance indicators, intestinal morphology, carcass characteristics, lymphoid organs, and selected blood indices of broiler chickens. A total of 816 1-day-old male broilers (Ross 308) were used and randomly divided into six blocks as replicates with eight treatments per block (forty-eight floor pens) based on 4 × 2 factorial arrangements with four dietary treatments containing 0.00% (CONT), 0.12% gum arabic (T1), 0.25% gum arabic (T2), and 0.10% commercial prebiotic (T3) and two stocking densities (normal = 28 kg/m2; high = 50 kg/m2). All performance indicators were evaluated during the feeding phases. Blood biochemical indicators were analyzed at 36 days of age. At 37 days of age, carcass characteristics, lymphoid organs, and intestinal morphology were measured. On days 1-36, growth performance indicators were negatively affected at high stocking density, but all growth performance indicators except feed intake improved in chickens receiving T1-T3 compared to CONT (p < 0.05). The relative weight of total small intestine and weight-to-length ratio showed a significant interaction between treatments and stocking density (p < 0.05). A high stocking density decreased pre-slaughter weight, carcass weight, and dressing yield, while legs and thymus increased (p < 0.05). None of the interactions or treatments affected carcass characteristics or lymphoid organs (p > 0.05). Indicators of blood biochemistry were not affected by treatments, stocking density, or their interaction (p > 0.05), except for uric acid, creatinine, and aspartate aminotransferase, which were higher at a high stocking density (p < 0.05). In conclusion, gum arabic as a prebiotic improved growth performance, production efficiency, and intestinal morphology in broilers. In contrast, high stocking density negatively affected performance, production efficiency, some blood indices, carcass weight, dressing yield, and intestinal morphology. Further research is needed to determine the mechanism.

Dietary tea tree (Melaleuca alternifolia) essential oil as alternative to antibiotics alleviates experimentally induced Eimeria tenella challenge in Japanese quails

Coccidiosis is one of the most common infectious diseases seen in Japanese quails. The current study was conducted to evaluate the impact of tea tree essential oil (TTEO) on growth performance and intestinal health of quails in response to Eimeria tenella challenge. A total of 250 Japanese quails were divided into five treatments: untreated uninfected (negative control); untreated infected (positive control); infected + Amprolium; infected and 1% TTEO; infected and 2% TTEO. Except negative control, all groups were orally dosed with 5 × 10⁴ sporulated oocysts of E. tenella. The results revealed that supplementation of 1% TTEO and treatment of amprolium improved feed intake, weight gain and feed conversion ratio in infected quails compared to the positive control. Similarly, lesion score and mortality was significantly (p < 0.01) reduced in quails supplemented with 2% TTEO and amprolium treated birds. Moreover, oocysts counts and histological features of caecum in infected birds were reversed in 1% TTEO and amprolium treatment. The histological findings of amprolium and 1% TTEO supplemented quails showed intact intestinal villi with mild sloughed epithelium. In conclusion, 1% TTEO can be safely used to control coccidiosis in Japanese quails as natural effective compound.

Combined impact of lemongrass and spearmint herbs on performance, serum metabolites, liver enzymes, and meat quality of broiler

Objectives

This study aimed to assess the influence of feeding fresh lemongrass (Cymbopogon citratus) or spearmint (Mentha spicata) and their combination on performance, serum metabolites, liver enzymes, and meat quality in broilers.

Materials and Methods

A total of 168 day-old Indian River chicks were arbitrarily offered four experimental rations: (i) control ration (CT-R): corn-soya-based ration, (ii) lemongrass ration (LG-R): CT-R + 1.0% DM of lemongrass; (iii) spearmint ration (SM-R): CT-R + 1.0% DM of spearmint; and (iv) lemongrass-spearmint ration (LS-R): CT-R + 0.5% DM from both lemongrass and spearmint. Each ration was given to 42 birds for a duration of 35 days, with 3 replications and 14 birds each.

Results

Elevated body weight gain was observed in LG-R (1,502 gm), LS-R (1,492 gm), and SM-R (1,474 gm) compared to CT-R (1,451 gm) (p = 0.078). Herbal rations successfully reduced almost 3%-5% of serum and meat total cholesterol concentrations compared to CT-R. Compared to CT-R, the highest zinc and iron concentrations of serum and meat were measured in LG-R and SM-R, respectively, while both minerals of serum and meat were observed to be better in LS-R (p < 0.05). Herbal rations significantly improved serum liver enzyme activity and ameliorated the red color of breast and thigh meat but failed to improve the lightness and yellowness of both types of meat compared to CT-R.

Conclusions

LG-R, SM-R, and LS-R improved bird performance, liver health, and meat color, and lowered serum and meat cholesterol levels. But among them, LS-R efficaciously increased the serum and meat zinc and iron concentrations.

Comparative Proteomic Analysis Revealed the Mechanism of Tea Tree Oil Targeting Lipid Metabolism and Antioxidant System to Protect Hepatopancreatic Health in Macrobrachium rosenbergii

Tea tree oil (TTO) is a pure natural plant essential oil. The studies evaluated the hepatopancreas lipid metabolism and antioxidant efficacy of Macrobrachium rosenbergii fed with 0 (CT group) and 100 mg/kg TTO (TT group) by label-free quantification proteomic analysis. Compared to the CT group, the TT group improved growth performance and increased the survival rate after stress. Dietary TTO also decreased hemolymph AST and ALT activities and decreased hepatopancreatic vacuolation. At the same time, hepatopancreas lipids droplets and hemolymph lipids (TG, TC, LDL-C) were decreased, and the peroxidation products content (MDA, LPO, 4-HNE) was also decreased. In addition, the levels of hepatopancreas antioxidant enzymes (T-AOC, CAT, and SOD) were increased in the TT group. With proteomic analysis, a total of 151 differentially expressed proteins (DEPs) (99 up-regulated and 52 down-regulated) were identified in the hepatopancreas. Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein-protein interaction analysis showed that the 16 DEPs have interactions, which are mainly involved in the pathways related to lipid metabolism (fatty acid biosynthesis, fatty acid metabolism, glycerophospholipid metabolism) and redox reaction (cytochrome P450 enzyme systems). Furthermore, the mRNA expression of 15 proteins followed the proteomic analysis with qRT-PCR validation. Pearson correlation analysis showed that fatty acids and glycerophospholipid metabolism-related proteins were highly correlated to peroxide content, glycerophospholipid metabolism, and cytochrome P450 system-related proteins (CYP1A1, GSTT1, GPX4) were highly correlated to AST and ALT. Additionally, GPX4 is closely related to peroxide content and antioxidant enzyme activity. Our results revealed that TTO plays a protective role in the hepatopancreas targeting the critical enzymes and antioxidant reactions in lipid metabolism. Provides a new perspective to elucidate the action path of TTO in protecting invertebrate hepatopancreas, highlights the influence of lipid metabolism on hepatopancreas health and the interaction between lipid metabolism and antioxidant system in the regulation of TTO.

Morphological and molecular characterization of Ascaridia columbae in the domestic pigeon (Columba livia domestica) and the assessment of its immunological responses

Parasitism is a divesting problem that is frequently overlooked and may result in severe prominent clinical manifestation. This study aimed to investigate the seasonal and sexual prevalence of the gastrointestinal nematode Ascaridia columbae (A. columbae) infection among domestic pigeons in Giza governorate, Egypt, during the period from 2020 to 2021. One hundred and sixty suspected pigeons were clinically investigated. Blood & tissue samples were collected from infected birds to estimate serum zinc concentration, malondialdehyde (MDA), and nitric oxide levels. As well as tumor necrosis factor-alpha (TNF-α), interleukin 1β (IL1β) activity, and histopathological examination were estimated; also, worms were collected for morphological identification using electron microscope (SEM) and molecularly identified using polymerase chain reaction (PCR), further sequenced, and submitted in GenBank with accession number MZ343369. The average ascarid (length × breadth) were 72.4 ± 3.3 µm (70.5 - 79.9 µm) × 39.9 ± 2.5 µm (37.6 - 42.3 µm). The distinguishing morphological characteristics that have been noticed in ascarid worms were creamy white, cylindrical worm with triradiate lips with wide cephalic alae extending on both the lateral sides and filariform esophagus. In males, spicules were almost equal with the presence of precloacal chitinous-rimmed sucker. The prevalence of A. columbae infection was (63.1%) with a higher incidence in females (79.2%) than males (46.1%). The highest seasonal prevalence was observed in winter (92.5%), followed by summer and spring (87.5% and 55%), respectively while, the lowest prevalence was observed in autumn (17.5%). The intensity of worms in the infected intestine varied from 5 to 120 adult worms. The histopathological examination revealed the presence of chronic diffuse moderate catarrhal enteritis with roundworms in the lumen. Infected birds showed a significant increase in nitric oxide and MDA levels while serum zinc levels were lowered in infected pigeons. Infected pigeons revealed a marked increase in IL1-β and TNFα than apparently healthy ones.

Necrotic enteritis in broiler chickens: disease characteristics and prevention using organic antibiotic alternatives – a comprehensive review

In line with the substantial increase in the broiler industry worldwide, Clostridium perfringens-induced necrotic enteritis (NE) became a continuous challenge leading to high economic losses, especially after banning antimicrobial growth promoters in feeds by many countries. The disease is distributed worldwide in either clinical or subclinical form, causing a reduction in body weight or body weight gain and the feed conversion ratio, impairing the European Broiler Index or European Production Efficiency Factor. There are several predisposing factors in the development of NE. Clinical signs varied from inapparent signs in case of subclinical infection (clostridiosis) to obvious enteric signs (morbidity), followed by an increase in mortality level (clostridiosis or clinical infection). Clinical and laboratory diagnoses are based on case history, clinical signs, gross and histopathological lesions, pathogenic agent identification, serological testing, and molecular identification. Drinking water treatment is the most common route for the administration of several antibiotics, such as penicillin, bacitracin, and lincomycin. Strict hygienic management practices in the farm, careful selection of feed ingredients for ration formulation, and use of alternative antibiotic feed additives are all important in maintaining broiler efficiency and help increase the profitability of broiler production. The current review highlights NE caused by C. perfringens and explains the advances in the understanding of C. perfringens virulence factors involved in the pathogenesis of NE with special emphasis on the use of available antibiotic alternatives such as herbal extracts and essential oils as well as vaccines for the control and prevention of NE in broiler chickens.

Antioxidant and antimicrobial activities of phytonutrients as antibiotic substitutes in poultry feed

Globally, there is increasing demand for safe poultry food products free from antibiotic residues. There is thus a need to develop alternatives to antibiotics with safe nutritional feed derivatives that maximize performance, promote the intestinal immune status, enrich beneficial microbiota, promote health, and reduce the adverse effects of pathogenic infectious microorganisms. With the move away from including antibiotics in poultry diets, botanicals are among the most important alternatives to antibiotics. Some botanicals such as fennel, garlic, oregano, mint, and rosemary have been reported to increase the poultry's growth rate and/or feed to gain ratio. Botanicals' role is assumed to be mediated by improved immune responses and/or shifts in the microbial population in the intestine, with the elimination of pathogenic species. In addition, modulation of the gut microbiota resulted in various physiological and immunological responses and promoted beneficial bacterial strains that led to a healthy gut. There is thus a need to understand the relationship between poultry diets supplemented with botanicals and good health of the entire gastrointestinal tract if we intend to use these natural products to promote general health status and production. This current review provides an overview of current knowledge about certain botanicals that improve poultry productivity by modulating intestinal health and reducing the negative impacts of numerous pathogenic bacteria. This review also describes the efficacy, negative effects, and modes of action of some common herbal plants applied in poultry as alternatives to reduce the use of antibiotics.

The importance of nutrition in alleviating high stocking density stress in poultry

In recent decades, the number of birds reared per unit area has dramatically spiked to increase profitability in egg and meat production. However, nowadays, the increase in sensitivity to animal welfare and consumer demands brings along with it a raised interest in stocking density. Stocking density is defined either as the number of animals or body weight per unit area or as the area per animal. High stocking density, which is a stress factor, can be defined as an increase in the number of animals per unit area or a decrease in the area per animal. Stress caused by high stocking density negatively affects the bird’s physiology and performance as well as the quality of the product obtained. The ideal stocking density should be 9 laying hens, 35 kilogrammes for broilers, and 45 quails per square metre. Otherwise, one will observe stress indicators in birds reared in more than the recommended stocking density per unit area and, consequently, a decrease in bird growth, egg production, feed efficiency, and egg or meat quality. Apart from increasing the concentrations of amino acids such as lysine, methionine, tryptophan and arginine, minerals such as selenium and chromium, and vitamins such as C and E in the diet, the addition of additives such as probiotics, humates, phytophenol compounds, and propolis is also effective in reducing or eliminating these negative effects caused by high stocking density. As a result, regulations in the nutrition of animals are effective in reducing/preventing such negative effects, thus improving animal welfare and ensuring the maintenance of optimum yield.