Animal Sciences Commons^™

Development Of Real-Time Pcr Assay For Quantitative Detection Of Clostridium Septicum, Bishnu Adhikari, Guillermo Tellez-Isaias, Tieshan Jiang, Brian Wooming, Young Min Kwon

Poultry Science Faculty Publications and Presentations

Cellulitis is an important disease in commercial turkey farms associated with significant economic loss. Although the etiology of cellulitis is not fully elucidated, Clostridium septicum (C. septicum) is one of the main causes of this infectious disease. In this study, we report the development of a quantitative real-time PCR (qRT PCR) assay targeting the alpha-toxin gene (csa), which involves a prior 15-cyle PCR using a nested pair of primers to increase the detection sensitivity. Additionally, the TaqMan probe was employed to increase the target-specificity of the assay. The performance of our nested qRT-PCR assay …

Phenotypic And Functional Characterization Of Bovine Adipose-Derived Mesenchymal Stromal Cells, Vitali V. Maldonado, Sriya Pokharel, Jeremy G. Powell, Rebekah M. Samsonraj Dr.

Animal Science Faculty Publications and Presentations

Background: Mesenchymal stem cells (MSCs) are increasingly trialed in cellular therapy applications in humans. They can also be applied to treat a range of diseases in animals, particularly in cattle to combat inflammatory conditions and aging-associated degenerative disorders. We sought to demonstrate the feasibility of obtaining MSCs from adipose tissue and characterizing them using established assays. Methods: Bovine adipose MSCs (BvAdMSCs) were isolated using in-house optimized tissue digestion protocols and characterized by performing a colony formation assay, cell growth assessments, cell surface marker analysis by immunocytochemistry and flow cytometry, osteogenic and adipogenic differentiation, and secretion of indoleamine 2,3-dioxygenease (IDO). Results: …

Evaluating Supplementation Programs For Growing Calves Grazing Bermudagrass Pastures, A. M. Womack, Beth Kegley, Shane Gadberry, T. Hess, D. Hubbell, P. A. Beck

Animal Science Faculty Publications and Presentations

Objective

Materials and Methods

Investigation Of Potential Gut Health Biomarkers In Broiler Chicks Challenged By Campylobacter Jejuni And Submitted To A Continuous Water Disinfection Program, Tilemachos Mantzios, Despoina E. Kiousi, Georgia D. Brellou, Georgios A. Papadopoulos, Vangelis Economou, Marili Vasilogianni, Elisavet Kanari, Evanthia Petridou, Ilias Giannenas, Guillermo Tellez-Isaias, Aglaia Pappa, Alex Galanis, Vasilios Tsiouris

Poultry Science Faculty Publications and Presentations

The exploration of novel biomarkers to assess poultry health is of paramount importance, not only to enhance our understanding of the pathogenicity of zoonotic agents but also to evaluate the efficacy of novel treatments as alternatives to antibiotics. The present study aimed to investigate potential gut health biomarkers in broiler chicks challenged by Campylobacter jejuni and subjected to a continuous water disinfection program. A total of 144 one-day-old hatched broiler chicks were randomly allocated to four treatment groups with four replicates each, according to the following experimental design: Group A received untreated drinking water; Group B received drinking water treated …

Ecotoxicity Of Commonly Used Oilfield-Based Emulsifiers On Guinean Tilapia (Tilapia Guineensis) Using Histopathology And Behavioral Alterations As Protocol, Davies Ibienebo Chris, Okechukwu Kenneth Wokeh, Guillermo Tellez-Isaias, Zulhisyam Abdul Kari, Mohamed Nor Azra

Poultry Science Faculty Publications and Presentations

This study examined the histological aberrations in the gill and liver tissues and behavioural changes of Tilapia guineensis fingerlings exposed to lethal concentrations of used Oilfield-based emulsifiers for 96 h. Various concentrations of the surfactants were tested, ranging from 0.0 to 15.0 ml/L. The behaviour of the fish was observed throughout the experiment, and the results showed that increasing concentrations of the surfactants led to progressively abnormal behaviour, including hyperventilation and altered opercular beat frequency. These behavioural changes indicated respiratory distress and neurotoxic effects. Histological analysis revealed structural aberrations in the gill and liver tissues, with higher concentrations causing more …

Effects Of Supplementing Selenium-Enriched Cardamine Violifolia To Laying Hens On Egg Quality And Yolk Antioxidant Capacity During Storage At 4 °C And 25 °C, Hubei Key, Xin Cong, Hui Wang, Mengke Yan, Xianfeng Xu, Mingkang Liu, Fulong Song, Dan Wang, Xiao Xu, Jiangchao Zhao, Shuiyan Cheng, Yulan Liu, Huiling Zhu

Animal Science Faculty Publications and Presentations

Oxidative stress occurs in the process of egg storage. Antioxidants as feed additives can enhance egg quality and extend the shelf life of eggs. Selenium-enriched Cardamine violifolia (SEC) has strongly antioxidant properties. The objective of this study was to assess the effects of dietary supplementation with SEC on egg quality and the yolk antioxidant capacity of eggs stored at 4 °C and 25 °C. Four hundred fifty 65-week-old, Roman hens that were similar in laying rate (90.79 ± 1.69%) and body weight (2.19 ± 0.23 kg) were divided into 5 groups. The birds were fed diets supplemented with 0 mg/kg …

Inducing Experimental Bacterial Chondronecrosis With Osteomyelitis Lameness In Broiler Chickens Using Aerosol Transmission Model, Andi Asnayanti, Anh Dang Trieu Do, Khawla Alharbi, Adnan Alrubaye

Poultry Science Faculty Publications and Presentations

Lameness disease attributed to bacterial chondronecrosis with osteomyelitis in broilers affects production, animal welfare, and food safety in the poultry industry. The disease is characterized by necrotic degeneration of the rapidly growing femora and tibiae due to bacterial translocation from the respiratory or gastrointestinal tracts into the blood circulation, eventually colonizing the growth plate of the long bones. To investigate the etiology, pathogenesis, and intervention measures for BCO, developing an experimental model that reliably induces BCO lameness is of the utmost importance. In the past, we have employed a wire -flooring model and a litter -flooring model administered with a …

Can Steam Be Usable As A "Plus" For Ventilation Shutdown?, A. V. Mendoza, S. Weimer, Z. Williams

Poultry Science Faculty Publications and Presentations

The American Veterinary Medical Association (AVMA), preferred depopulation methods (i.e., foam, containerized gassing, and mechanical methods) can be challenging when depopulating cage and aviary commercial laying hen houses for multiple reasons. When preferred methods are not feasible or resources are unavailable, ventilation shutdown plus (VSD+) heat and/or carbon dioxide (CO₂) is approved for emergency situations. Both recognized “pluses” work but can have issues as VSD+ heat typically causes a decrease in environmental humidity and can affect PVC structures, while CO₂ can be a human safety concern and has procurement problem during emergencies. …

Efficacy Of Powdered Alfalfa Leaves To Ameliorate The Toxic Effects Of Aflatoxin B1 In Turkey Poults, M.J. Nava-Ramírez, Jesus A. Maguey-Gonzalez, S. Gomez-Rosales, J. O. Hernandez-Ramirez, Juan D. Latorre, Xiangwei Du, C. Lopez-Coello, Billy Hargis, G. Tellez-Isaias, A. Vasquez-Duran, A. Mendez-Albores

Poultry Science Faculty Publications and Presentations

Abstract

This experiment was conducted to determine the effect of an adsorbent material based on powdered alfalfa leaves added in the aflatoxin B₁ (AFB₁)-contaminated diet of turkey poults on production parameters, blood cell count, serum biochemistry, liver enzymes, and liver histology. For this purpose, three hundred and fifty female Nicholas-700 poults were randomly assigned into five treatments: (1) Control, AFB₁-free diet; (2) AF, diet contaminated with 250 ng AFB₁/g; (3) Alfalfa, AFB₁-free diet + 0.5% (w/w) adsorbent; (4) AF+alfalfa, diet contaminated with 250 ng AFB₁/g + 0.5% (w/w) adsorbent, …

Unraveling Frontiers In Poultry Health (Part 1) – Mitigating Economically Important Viral And Bacterial Diseases In Commercial Chicken And Turkey Production, Yowande O. Fasina, David L. Suarez, George D. Ritter, Elise C. Griffen, Yahua Z. Farnell, Ross Wolfenden, Billy M. Hargis

Poultry Science Faculty Publications and Presentations

This symposium offered up-to-date perspectives on field experiences and the latest research on significant viral and bacterial diseases affecting poultry. A highlight was the discussion on the use of enteroids as advanced in vitro models for exploring disease pathogenesis. Outcomes of this symposium included identifying the urgent need to improve the prevention and control of avian influenza by focusing research on vaccine effectiveness. In this regard, efforts should focus on enhancing the relatedness of vaccine antigen to the field (challenge) virus strain and improving immunogenicity. It was also revealed that gangrenous dermatitis could be controlled through withholding or restricting the …

Can Moderate-Quality Bermudagrass Baleage Be Used To Stretch Wheat Pasture?, P. A. Beck, M. R. Beck, D. Hubbell Iii, T. Hess, A. P. Foote, M. S. Gadberry, Beth Kegley

Animal Science Faculty Publications and Presentations

Objectives

Materials and Methods

Clostridium Butyricum And Carbohydrate Active Enzymes Contribute To The Reduced Fat Deposition In Pigs, Lingyan Ma, Shiyu Tao, Tongxing Song, Wentao Lyu, Ying Li, Wen Wang, Qicheng Shen, Yan Ni, Jiang Zhu, Jiangchao Zhao, Hua Yang, Yingping Xiao

Animal Science Faculty Publications and Presentations

Pig gastrointestinal tracts harbor a heterogeneous and dynamic ecosystem populated with trillions of microbes, enhancing the ability of the host to harvest energy from dietary carbohydrates and contributing to host adipogenesis and fatness. However, the microbial community structure and related mechanisms responsible for the differences between the fatty phenotypes and the lean phenotypes of the pigs remained to be comprehensively elucidated. Herein, we first found significant differences in microbial composition and potential functional capacity among different gut locations in Jinhua pigs with distinct fatness phenotypes. Second, we identified that Jinhua pigs with lower fatness exhibited higher levels of short-chain fatty …

A Comprehensive Analysis Of Antibiotic Resistance Genes In The Giant Panda Gut, Feilong Deng, Yanhua Han, Yushan Huang, Desheng Li, Jianmin Chai, Linhua Deng, Ming Wei, Kai Wu, Huabin Zhao, Guan Yang, Jiangchao Zhao, Ying Li, Chengdong Wang

Animal Science Faculty Publications and Presentations

In this study, we have successfully constructed a comprehensive database of metagenome-assembled genomes (MAGs) pertaining to the gut microbiota of the giant panda. Through our analysis, we have identified significant reservoirs of antibiotic resistance genes (ARGs), namely Escherichia coli, Citrobacter portucalensis, and Klebsiella pneumoniae. Furthermore, we have elucidated the primary contributors to ARGs, including Streptococcus alactolyticus and Clostridium SGBP116, in both captive and wild pandas. Additionally, our findings have demonstrated a higher prevalence of ARGs in the metagenome, with notable expression of the RPOB2 gene in S. alactolyticus. Crucially, 1217 ARGs shared homology with human gut …

Antimicrobial Tolerance In Salmonella: Contributions To Survival And Persistence In Processing Environments, Tomi Obe, Aaron S. Kiess, Ramakrishna Nannapaneni

Poultry Science Faculty Publications and Presentations

Salmonella remains a top bacterial pathogen implicated in several food-borne outbreaks, despite the use of antimicrobials and sanitizers during production and processing. While these chemicals have been effective, Salmonella has shown the ability to survive and persist in poultry processing environments. This can be credited to its microbial ability to adapt and develop/acquire tolerance and/or resistance to different antimicrobial agents including oxidizers, acids (organic and inorganic), phenols, and surfactants. Moreover, there are several factors in processing environments that can limit the efficacy of these antimicrobials, thus allowing survival and persistence. This mini-review examines the antimicrobial activity of common disinfectants/sanitizers used …

Effects Of Environmental Enrichments On Welfare And Hepatic Metabolic Regulation Of Broiler Chickens, Seong W. Kang, Karen D. Christensen, Michael T. Kidd, Sara K. Orlowski

Poultry Science Faculty Publications and Presentations

The aims of this study were to find suitable environmental enrichment (EE) and evaluate the combined effect of two EEs, variable light intensity (VL) lighting program and EH, on mental health and hepatic metabolic regulation in commercial broilers. To find the advantageous EEs for broilers, three different EEs (board, hut, and ramp) were tested in trial 1. EEs were placed and the engagement of birds to EEs, dustbathing behavior, and daily physical activity were observed. Birds treated with huts showed higher engagement than the board- or ramp-treated birds (p < 0.05). The results of dustbathing behavior and daily physical activity indicated that the environmental hut (EH) is the most favorable enrichment for broilers. In the second trial, to test the effect of EHs on mental health and hepatic metabolic conditions, the brain and liver were sampled from the four treatment birds (20 lx_Con, 20 lx_Hut, VL_Con and VL_Hut) on day 42. The lower expression of TPH2 (tryptophan hydroxylase 2) of VL_Hut birds than those of VL_Con and 20 lx_Hut treated birds suggests the combining effect of EHs with the VL lighting program on the central serotonergic homeostasis of broilers. Reduced expressions of TH (tyrosine hydroxylase), GR (glucocorticoid receptor), BDNF (brain-derived neurotrophic factor) of VL_Hut treated birds compared to those of VL_Con and 20 lx_Hut birds suggest lower stress, stress susceptibility, and chronic social stress in VL_Hut treated birds. The expression of CPT1A (carnitine palmitoyl transferase 1) increased over three-fold in the liver of VL_Con birds compared to 20 lx_Con birds (p < 0.05). EHs treatment in VL birds (VL_Hut) significantly decreased CPT1A but not in 20 lx birds (20 lx_Hut). The expression of ACCα (acetyl-CoA carboxylase alpha) was significantly decreased in VL_Con birds compared to 20 lx_Con birds. There was no significant difference in the hepatic FBPase (fructose-1,6-bisphosphatase), GR, and 11β-HSD1 (11 β-hydroxysteroid dehydrogenease-1) expression between 20 lx_Con and VL_Con birds, but EHs significantly stimulated GR in 20 lx_Hut birds, and stimulated FBPase and 11β-HSD1 expression in the VL_Hut birds compared to 20 lx_Con birds, suggesting that the VL lighting program reduced fatty acid synthesis and increased fatty acid β-oxidation in the broilers’ liver and VL_Hut improved the hepatic de novo glucose production. Taken together, the results suggest that the stimulated voluntary activity by EHs in the light-enriched broiler house improved mental health and hepatic metabolic function of broilers and may indicate that the improved hepatic metabolic function contributes to efficient nutritional support for broilers.

Research Note: Evaluation Of Phytic Acid Disappearance, Ileal P Digestibility, And Total Tract P Retention In Canola Meal Supplemented With Increasing Levels Of Exogenous Phytase Using Conventional And Cecectomized Precision-Fed Roosters And Growing Chicks, Benjamin Parsons, Samuel Rochell

Poultry Science Faculty Publications and Presentations

Apparent ileal digestibility (AID) of P, apparent total tract retention (ATTR) of P, and phytic acid disappearance in canola meal were evaluated in the presence of increasing levels of exogenous phytase. In Experiment 1, a precision-fed rooster assay was used to determine phytic acid (myo-inositol 1,2,3,4,5,6-hexakis; InsP₆) and inositol phosphate (InsP_6-3; InsP-P) disappearance in conventional and cecectomized Leghorn roosters. Roosters were crop intubated with 25 g of canola meal mixed with 0, 500, 1,000, or 2,000 FTU/kg of exogenous phytase. In Experiment 2, InsP₆ and InsP-P disappearance and AID …

Leverage Of Salvadora Persica And Pulicaria Undulata Extracts In Escherichia Coli-Challenged Broiler Chickens, Mohamed A. Lebda, Ahd. A. Mansour, Esraa M. Elieba, Shahira A. Hassoubah, Fatemah Almalki, Mohamed Abu El-Magd, Sara I. Othman, Ahmed M. Allam, Guillermo Tellez-Isaias, Ayman E. Taha

Poultry Science Faculty Publications and Presentations

Escherichia coli (E. coli) is a significant challenge in the poultry industry due to their related use of antimicrobial compounds and the drastic losses in production and livability. This study investigated the preventive impacts of dietary supplementation of Salvadora persica (SP) and/or Pulicaria undulata (PU) extracts on growth traits, biochemical and immune parameters, and related gene expression of E. coli-infected broilers. A total of 120 one-day-old Cobb broilers were used. The chicks were allocated into eight equal groups (3 replicates/ group; 5 chicks per each replicate) as follows: G1; control negative, G2; SP-treated, G3; …

Metagenomics Reveals The Temporal Dynamics Of The Rumen Resistome And Microbiome In Goat Kids, Jianmin Chai, Yimin Zhuang, Kai Cui, Yanglin Zhu, Yangliang Bi, Naifeng Zhang

Animal Science Faculty Publications and Presentations

Background

The gut microbiome of domestic animals carries antibiotic resistance genes (ARGs) which can be transmitted to the environment and humans, resulting in challenges of antibiotic resistance. Although it has been reported that the rumen microbiome of ruminants may be a reservoir of ARGs, the factors affecting the temporal dynamics of the rumen resistome are still unclear. Here, we collected rumen content samples of goats at 1, 7, 14, 28, 42, 56, 70, and 84 days of age, analyzed their microbiome and resistome profiles using metagenomics, and assessed the temporal dynamics of the rumen resistome in goats at the early …

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 25 2024, Several Authors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Letter From The Faculty Editor, Beth Kegley

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Featured Faculty Mentor/Student Team, Austin Jones, Ashley Dowling, Baylie Day

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Evaluating Efficiency And Accuracy Of Three Texture Analysis Methods For Blackberry Fruit, Rhys M. Brock, Carmen Johns, Katelyn Lust-Moore, Margaret Worthington

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

A major objective of the University of Arkansas System Division of Agriculture (UADA) Fruit Breeding program is to improve the texture of blackberry (Rubus subgenus Rubus Watson). Blackberry varieties with improved fruit firmness transport and store well and may maintain superior quality under challenging postharvest conditions than softer varieties. Increased firmness may also make cultivars less susceptible to red drupelet reversion (RDR), a postharvest disorder of blackberries in which fully black drupelets revert to red after harvest. This research project aims to assess the efficiency and accuracy of three methods applied in evaluating blackberry firmness. The study compares instrumental analysis …

Stream Restoration Effectiveness In Mullins Creek In Fayetteville, Arkansas, Amadeo Scott, Shannon Speir

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Lotic waterways are vital for habitat, food, water, and flood protection, but urbanization poses a major threat to their integrity. Runoff from urban surfaces leads to pollution, flashiness, loss of biodiversity, and other symptoms, also known as Urban Stream Syndrome (USS). Streams can be restored in order to combat USS, but most restorations are not monitored, so their long-term effectiveness is unknown. This study quantitatively evaluated a decade-old stream restoration in Fayetteville, Arkansas, to assess its effectiveness in combating USS and achieving set restoration goals, and to gain insights for future restoration projects. Restoration goals included decreasing erosion and sedimentation, …

Diet And Monensin Influence The Temporal Dynamics Of The Rumen Microbiome In Stocker And Finishing Cattle, Jianmin Chai, Caleb P. Weiss, Paul A. Beck, Wei Zhao, Ying Li, Jiangchao Zhao

Animal Science Faculty Publications and Presentations

Background

Stocker cattle diet and management influence beef cattle performance during the finishing stage, but knowledge of the dynamics of the rumen microbiome associated with the host are lacking. A longitudinal study was conducted to determine how the feeding strategy from the stocker to the finishing stages of production affects the temporal dynamics of rumen microbiota. During the stocker phase, either dry hay or wheat pasture were provided, and three levels of monensin were administrated. All calves were then transported to a feedlot and received similar finishing diets with or without monensin. Rumen microbial samples were collected on d 0, …

Letter From The Dean, Jeff Edwards

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Contents, Discovery Editors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Instructions For Authors, Discovery Editors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Vitamin C And/Or Garlic Can Antagonize The Toxic Effects Of Cadmium On Growth Performance, Hematological, And Immunological Parameters Of Growing Japanese Quail, Waleed M. Dosocky, Soha A. Farag, Areej A/ Almuraee, Islam M. Youssef, Ohaad F.A. Awlya, Wafaa F. Abusudah, Alaah Qadhi, Ahmad F. Arbaeen, Mahmoud Moustafa, Hesham Hassan, Guillermo Tellez-Isaias

Poultry Science Faculty Publications and Presentations

This study used 300 1-day-old, sexless, developing chicks of Japanese quail to estimate the ability of vitamin C and/or garlic to antagonize the venomous influence of cadmium (Cd) on the hematological, immunological, and performance characteristics of developing Japanese quail. The quail was separated into 5 similar groups of 60 chicks apiece, and 6 duplicates (10 each) were given to each sub-group. The control group received a basal diet without any supplements. The Cd group was nourished with a basal diet of + 80 mg cadmium chloride (CdCl₂)/kg diet. The 3rd group was fed a basal diet …

In Vitro And In Vivo Evaluation Of Antimicrobial Activity, Oocyst Sporulation Rate, Oocyst Integrity And Oocyst Infectivity In Eimeria Maxima M6 Oocyst Suspensions Treated With Chlorhexidine Salts In Comparison With Potassium Dichromate, Lauren Laverty

Graduate Theses and Dissertations

Eimeria species oocysts cause coccidiosis, one of the costliest diseases in the poultry industry. Coccidiosis infections cause significant economic losses due to reduced performance in chickens and turkeys. The objective of this thesis was to determine fecal bacterial recovery from chlorhexidine (CHX) salt suspensions containing Eimeria maxima M6 oocysts and evaluate the effect of CHX salts on oocysts during long-term cold storage. For bacterial recovery experiments, CHX digluconate and CHX gluconate were tested at different concentrations on poultry fecal slurries during oocyst shedding. Eimeria maxima M6 oocysts were evaluated in CHX salt suspensions to test the effect on oocyst degradation …

Determination Of P Availability In Feedstuffs And The Effect Of Feedstuffs And Anti-Nutritional Factors On Secretory Iga Production And Host Nutrient Losses In Poultry, Benjamin Parsons

Graduate Theses and Dissertations

The availability of P in feedstuffs and the effect of feedstuffs, feed additives, and anti-nutritional factors on secretory IgA (sIgA) production in chickens were evaluated. A rapid method was developed using the precision-fed rooster assay to evaluate phytic acid disappearance, P digestibility, and phytase efficacy. Further, exogenous phytase was found to be effective at degrading myo-inositol 1,2,3,4,5,6-hexakis, however, the enzyme was less efficient at P release from lower inositol phosphates. The availability of P in feedstuffs was found to be affected by dietary Ca content, where increasing Ca linearly reduced (P < 0.05) both phytic acid hydrolysis and P digestibility. For example, the standardized ileal digestibility of P was reduced from 73 to 47% in soybean meal when the dietary Ca content was increased from 0.30 to 0.75%. The digestibility of P in distillers dried grains with solubles (DDGS) and corn fermented protein (CFP), however, was high across all Ca levels (71 to 80%). Relative P bioavailability based on tibia bone ash was also found to be high for DDGS and CFP, being 81 and 78%, respectively. Upon further evaluation, it was observed that utilizing low dietary Ca levels (0.30%) when P digestibility in individual plant-based feedstuffs was determined overestimated the P digestibility in practical grower diets by up to 16 percentage units. Utilization of higher Ca levels (0.75%) when P digestibility in individual plant-based feedstuffs was determined, however, resulted in calcualted P digestibility values that were within 1 to 3 percentage units of the measured digestibility in practical grower diets. Aside from P, feedstuffs were also evaluated to determine their effect on sIgA production in the intestine. Roosters excreted approximately 6 to 30 mg of sIgA / 24 h. Further, the proportional contribution of sIgA to total endogenous amino acid (AA) losses ranged from 1 to 13%, with the greatest contribution being observed for Trp. The addition of casein to a protein-free diet increased (P < 0.05) sIgA production in both roosters and broiler chickens. There was no change (P > 0.05) in sIgA production compared with the protein-free diet …