Journal of Applied Poultry Research最新文献

{"title":"Precise nutrition 1: Standardization of the KOH protein solubility test for soybean meal in a single commercial laboratory and correlation to in vivo poultry amino acid digestibility","authors":"Nelson Ruiz ,&nbsp;Carl M. Parsons ,&nbsp;Brian Steinlicht ,&nbsp;Dave Taysom ,&nbsp;Xin Wu ,&nbsp;Fiona Liu","doi":"10.1016/j.japr.2025.100550","DOIUrl":"10.1016/j.japr.2025.100550","url":null,"abstract":"<div><div>The KOH protein solubility (<strong>KOHPS</strong>) method to evaluate if a lot of commercial soybean meal (<strong>SBM</strong>) has undergone the Maillard reaction during processing was introduced to the animal feed industry by Araba and Dale (1990). Although it is used worldwide, there are 2 limitations that have not been addressed. There is large inter-laboratory variability of the test and an absence of a quantitative interpretation of the results in terms of amino acid (<strong>AA</strong>) digestibility that can be used by nutritionists and formulators for commercial SBM affected by the Maillard reaction. The objective of this study was to standardize the KOHPS method in a single commercial laboratory starting from the description by Araba and Dale (1990) by using commercial SBM samples whose in vivo AA digestibility status was known. For this purpose, 2 SBM samples, one with high solubility (80 to 85 % KOHPS) and another with low solubility (KOHPS ∼ 50 %), were used as reference samples to develop a preliminary protocol. Then adjustments in intensity of agitation were made with 4 SBM samples of known in vivo digestible Lys coefficients (0.88 to 0.96) to yield KOHPS values from 80 % to 85 %. The standardized protocol yielded KOHPS values from 50 to 56 % for the low solubility SBM reference sample and 3 samples known to have low in vivo digestible Lys coefficients (0.73 to 0.77). In conclusion, a standardized protocol is now available for the determination of KOHPS of commercial SBM that will allow regression equations to be developed for the estimation of digestible AA.</div></div>","PeriodicalId":15240,"journal":{"name":"Journal of Applied Poultry Research","volume":"34 3","pages":"Article 100550"},"PeriodicalIF":1.6,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144290559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mycotoxins as antinutritional factors: occurrence, impacts and management","authors":"Alexandra C. Weaver","doi":"10.1016/j.japr.2025.100543","DOIUrl":"10.1016/j.japr.2025.100543","url":null,"abstract":"<div><div>Mycotoxins are chemical metabolites produced by a variety of mold species. While mycotoxin form and concentration can vary from year to year, by location and by feedstuff type, mycotoxins are a contaminant that has global reach and has potential to influence the health of both animals and humans. In poultry, the negative effects of mycotoxins may be observed through changes in growth performance and efficiency, damage to internal organs, alterations in nutrient and mineral status, changes to hormone regulation and reproduction, and impaired immune function which could result in poor vaccination response or increased disease occurrence. Together, these effects lead to an overall reduction in production performance and bird health. Given the chemical nature of mycotoxins and their negative effects on birds, mycotoxins are similar to another category of compounds called antinutritional factors. These compounds are also metabolites, in this case produced by plants, that can result in adverse effects when consumed by birds. Attention has been given to antinutritional factors by poultry producers and nutritionists, and mycotoxins certainly deserve the same level of concern. However, through analysis of feedstuffs and feeds, understanding of mycotoxin risk, and proper management techniques, producers have the ability to mitigate the challenges posed by mycotoxins.</div></div>","PeriodicalId":15240,"journal":{"name":"Journal of Applied Poultry Research","volume":"34 3","pages":"Article 100543"},"PeriodicalIF":1.6,"publicationDate":"2025-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144107799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Handling and loading market-ready turkeys – Focus groups exploring the perspectives of live haul crew workers in the turkey industry","authors":"Luz A. Hernandez ,&nbsp;Victoria R. Merenda ,&nbsp;Monique D. Pairis-Garcia ,&nbsp;Maria Coady ,&nbsp;Alejandro Amaya ,&nbsp;Jesse L. Grimes ,&nbsp;Allison N. Pullin","doi":"10.1016/j.japr.2025.100547","DOIUrl":"10.1016/j.japr.2025.100547","url":null,"abstract":"<div><div>Improper handling and loading of market-ready turkeys during live haul presents significant challenges in the U.S. turkey industry. Bird injuries, such as bruises, scratches, and/or fractured or broken bones compromise animal welfare and lead to economic losses. However, the factors contributing to these handling challenges remain understudied. We aimed to identify barriers to implementing proper handling and loading techniques for market-ready turkeys through focus groups with commercial live haul crews. Participants identified three key themes: animal, farm, and human factors. Animal factors, such as bird sex, age, weight, and mobility, required crew members to modify handling strategies and varied the efficiency of live haul. The farm factors centered on the importance of preparing the barn environment for live haul. Adjusting lighting, ensuring good litter quality, scheduling nighttime shifts, using loading equipment correctly, and maintaining stable temperatures improve bird movement. Human factors included employee training methods, where informal training was the primary way in which crew members learned how to perform their tasks; the physical demands of the job, especially in challenging situations; and specific handling strategies to efficiently move birds and minimize injuries to animals and crew members. Animal, farm, and human factors are often interconnected, which compounds the complexity of ensuring proper animal handling for live haul. Future research in formal training, the design of farms, loading equipment, and personal protective equipment may mitigate the effects of these factors. Additionally, proactive teamwork and communication amongst veterinarians, producers, and live haul crews would better prepare farms for live haul.</div></div>","PeriodicalId":15240,"journal":{"name":"Journal of Applied Poultry Research","volume":"34 3","pages":"Article 100547"},"PeriodicalIF":1.6,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144290558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the impacts of xylo-oligosaccharides on growth performance of broiler chickens: A meta-analytical study","authors":"M. Naeem ,&nbsp;Dianna Bourassa ,&nbsp;Samuel Rochell ,&nbsp;Mike Bedford","doi":"10.1016/j.japr.2025.100546","DOIUrl":"10.1016/j.japr.2025.100546","url":null,"abstract":"<div><div>This meta-analytical study evaluated the impacts of xylo-oligosaccharide (XOS) supplementation on the growth performance of broiler chickens using data from 36 peer-reviewed studies, published between 2000 and 2024. The parameters analyzed included average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR). Results demonstrated that XOS supplementation increased (<em>P</em> &lt; 0.05) ADG by 6.445 % and ADFI by 1.544 %, and decreased (<em>P</em> &gt; 0.05) FCR by 7.147 %, compared to the control. Furthermore, XOS supplementation reduced the coefficient of variation (CV%) for ADG, ADFI, and FCR by 9.386 %, 5.759 %, and 4.037 %, respectively, indicating enhanced consistency in growth performance. Correlation analysis revealed a significant positive association between XOS levels and both ADG (R² = 0.023, <em>P =</em> 0.031) and ADFI (R² = 0.038, <em>P =</em> 0.009), while FCR showed no significant correlation (R² = 0.004, <em>P =</em> 0.391). A predictive model for ADG (R² = 0.850, RMSE = 0.135) accounted for 85 % of the variation and demonstrated reliability through cross-validation, making it a robust for forecasting growth performance based on XOS inclusion rates. The model also highlighted significant interactions between XOS levels and ADFI, suggesting that the effects of XOS are influenced by feed intake. These findings underscore the potential of XOS to optimize broiler productivity and sustainability. However, the variability in efficacy due to dietary composition, XOS purity, and environmental conditions warrants further investigation.</div></div>","PeriodicalId":15240,"journal":{"name":"Journal of Applied Poultry Research","volume":"34 3","pages":"Article 100546"},"PeriodicalIF":1.6,"publicationDate":"2025-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-phytate phosphorous requirements of pullets from 3 to 6 weeks of age and carryover effects of phosphorous deficiency at 18 weeks of age","authors":"A.M. Lyons,&nbsp;M.E. Persia","doi":"10.1016/j.japr.2025.100545","DOIUrl":"10.1016/j.japr.2025.100545","url":null,"abstract":"<div><div>The non-phytate phosphorous (nPP) requirement of 3 to 6 week old laying hen pullets was determined using body weight gain (BWG), mortality corrected feed conversion ratio (FCRm), tibia ash percent (TAP) and tibia ash weight (TAW). Potential carryover effects of early nPP deficiency at 12 and 18 wk were determined with the same parameters. A total of 1,008 Lohman LSL-Lite 3-week-old pullets were distributed across 42 cages and assigned 1 of 7 treatments (0.15, 0.22, 0.29, 0.36, 0.43, 0.49, and 0.56% nPP). There were 24 birds per cage and they were fed ad libitum. Pullets remained in respective treatment groups and phase-fed common diets from 6 to 18 wk. Body weight and FCRm were determined every 3 wk. At 6, 12, and 18 wk of age, 6, 2, and 2 pullets per pen, respectively, were euthanized for tibia ash determination. Data were analyzed using ANOVA in JMP Pro 16.0 and means were separated using Student’s t-test (P ≤ 0.05). Regression analysis from 3 to 6 wk was completed using BWG, FCRm, TAP, and TAW as response variables. The nPP requirement was 0.17% nPP for BWG, 0.14% nPP for FCRm, 0.16% nPP for TAP, and 0.14% nPP for TAW using linear broken line regression. The 0.15% nPP treatment from 3 to 6 wk reduced BW and TAW (P ≤ 0.05) at 6 wk of age. With at least 6 wk of recovery, measured parameters were not different starting at 12 wk (P &gt; 0.05). The nPP requirement for pullets from 3-6 wk of age was 0.16% to maximize bone ash percent with no carryover effects noted by 18 wk of age when adequate nPP was fed from 6 to 18 wks.</div></div>","PeriodicalId":15240,"journal":{"name":"Journal of Applied Poultry Research","volume":"34 3","pages":"Article 100545"},"PeriodicalIF":1.6,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143936988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review article: Recent advances in enzyme technologies for mitigating mycotoxin contamination in poultry feed","authors":"Christiane Gruber-Dorninger ,&nbsp;Markus Aleschko ,&nbsp;Andreas Höbartner-Gußl ,&nbsp;Sebastian Fruhauf ,&nbsp;Michaela Thamhesl ,&nbsp;Barbara Doupovec ,&nbsp;Dian Schatzmayr ,&nbsp;Wulf-Dieter Moll ,&nbsp;Chasity Pender","doi":"10.1016/j.japr.2025.100544","DOIUrl":"10.1016/j.japr.2025.100544","url":null,"abstract":"<div><div>Poultry feed is frequently contaminated with mycotoxins such as deoxynivalenol, zearalenone, fumonisins, aflatoxins, and ochratoxin A. As mycotoxins cause a variety of adverse effects, strategies to counteract the exposure of animals to these contaminants are urgently needed. The development of mycotoxin-inactivating feed enzymes shows great promise for mycotoxin risk management. In contrast to mycotoxin binders that are often applied as feed additives but known to effectively adsorb only some of the most prevalent mycotoxins (most notably aflatoxins), mycotoxin-inactivating enzymes can be tailor-made to specifically target each mycotoxin of concern. The development of mycotoxin-inactivating feed enzymes often starts with mining the natural diversity of enzymes that evolved in bacteria, fungi, plants, and animals. Promising enzyme candidates that lend themselves to biotechnological development are improved by enzyme engineering, formulated as feed additives, and rigorously tested in poultry feeding trials. Following this path, two feed enzymes were recently developed for inactivation of fumonisins and zearalenone in poultry, namely fumonisin esterase FumD (FUM<em>zyme</em>®) and zearalenone lactonase ZenA (ZEN<em>zyme</em>®). Upon ingestion, these enzymes effectively degrade their target mycotoxins to compounds of significantly reduced toxicity in the gastrointestinal tract of poultry. These successful developments highlight the great potential of mycotoxin-degrading feed enzymes.</div></div>","PeriodicalId":15240,"journal":{"name":"Journal of Applied Poultry Research","volume":"34 3","pages":"Article 100544"},"PeriodicalIF":1.6,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143928755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supplementation of live yeast (Saccharomyces cerevisiae) as natural feed additives on growth performance, meat quality and physiological status of broiler chickens","authors":"Maruf Hossain ,&nbsp;Amio Kante Das ,&nbsp;Kanan Talukder ,&nbsp;Md Momotaj Hossen ,&nbsp;Kanon Das ,&nbsp;Chondhon Bormon ,&nbsp;Mansur Ahmed ,&nbsp;Mohammad Al Mamun ,&nbsp;Mohammad Abujar Shuva ,&nbsp;Mahmoud Azzam ,&nbsp;Shad Mahfuz","doi":"10.1016/j.japr.2025.100542","DOIUrl":"10.1016/j.japr.2025.100542","url":null,"abstract":"<div><div>This study examined how supplementing broiler chickens with live yeast (<em>Saccharomyces cerevisiae</em>) affected their growth performance, carcass features, meat quality, hematological parameters, serum metabolic profile, and cecal bacterial counts. A total of 192 Arbor Acres broilers were randomly assigned to three treatment groups (8 replications, 8 chicks each). The dietary treatments were as follows: live yeast (600 mg/kg of basal diet), antibiotic (100 mg chlortetracycline /kg of basal diet), and control. Compared to control group, live yeast supplementation showed better feed conversion ratio (1.63 vs 1.83, <em>P</em> &lt; 0.05) and average daily weight grain (53.06 g/d vs 48.12 g/d, <em>P</em> &lt; 0.05) in whole study period. However, there were no appreciable variations (<em>P</em> &gt; 0.05) in the groups' respective feed consumption, internal organ weights and carcass traits. At 42 days of age, the broilers fed diets containing live yeast had a lower 7-day drip loss, a lower cooking loss, and a higher breast muscle pH at 45 min post-mortem (<em>P</em> &lt; 0.05) than the control group. Supplementing with live yeast also decreased serum triglycerides, total cholesterol, and heterophil/lymphocyte ratio (<em>P</em> &lt; 0.05). In comparison to the control, cecal bacterial examination showed lower <em>E. coli</em> and <em>Salmonella</em> spp. levels and higher <em>Lactobacillus</em> spp. counts in the LY and antibiotic groups. The findings indicated that inclusion of live yeast (<em>S. cerevisiae</em>) to the broilers diet can positively impact the development of growth, quality of meat, blood variables, and cecal microbiota of broilers. In conclusion, live yeast at 600 mg/kg of diet can be a viable substitute for antibiotic growth promoters for organic broiler production.</div></div>","PeriodicalId":15240,"journal":{"name":"Journal of Applied Poultry Research","volume":"34 3","pages":"Article 100542"},"PeriodicalIF":1.6,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of dietary inclusion of oyster mushroom (Pleurotus ostreatus) powder on live performance, physical meat quality, hemato-biochemical indices and cecal bacterial load in Sonali chickens","authors":"Atikul Islam ,&nbsp;Chondhon C. Bormon ,&nbsp;Kanon Das ,&nbsp;Momotaj Hossen ,&nbsp;Alvi H. Nimmi ,&nbsp;Sajib Paul ,&nbsp;Mohammad Al Mamun ,&nbsp;Mohammad Abujar Shuva ,&nbsp;Mahmoud Azzam ,&nbsp;Shad Mahfuz","doi":"10.1016/j.japr.2025.100540","DOIUrl":"10.1016/j.japr.2025.100540","url":null,"abstract":"<div><div>The current research aimed to assess the effects of oyster mushroom powder as potential alternative to antibiotic growth promoters on growth performance, physical meat quality, hemato-biochemical indices and cecal bacterial load in Sonali chickens. A total of 270 one-day-old male chicks were allotted in three experimental groups: control, antibiotic and mushroom. Each group had six replications of fifteen chicks. The control group was given a standard basal diet; the antibiotic group received basal diet plus 75 mg/kg chlortetracycline; and the mushroom group was fed oyster mushroom (<em>Pleurotus ostreatus</em>) powder (OMP) 300 mg/kg basal diet. Sonali chickens in mushroom group experienced significant improvements in the average daily gain (ADG), final body weight (FBW) and FCR than the control group. The mushroom group had a significant reduction in meat drip loss (at 30 days of aging) and cooking loss than both of antibiotic and control groups. Furthermore, OMP supplements significantly reduced serum LDLC, total cholesterol (TC), Urea–N and SGPT levels, while significantly elevated serum calcium and albumin than both control and antibiotic groups. Chickens in the mushroom and antibiotic group had a lower (<em>P</em> &lt; 0.05) <em>Enterobacter</em> and total aerobic bacterial population than control. In addition, <em>Lactobacillus spp</em>. were higher (<em>P</em> &lt; 0.05) in the mushroom group compared to the antibiotic and control groups. In summary, supplementing with 300 mg of OMP could be beneficial for safe broiler production due to its role in enhancing growth performance, improving meat quality, and supporting basic physiological and gut health functions.</div></div>","PeriodicalId":15240,"journal":{"name":"Journal of Applied Poultry Research","volume":"34 3","pages":"Article 100540"},"PeriodicalIF":1.6,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143890859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The comparative effects of ventilation shutdown with heat (VSDH), relative humidity (VSDHRh), or CO2 (VSDCO2) on broiler electroencephalogram (EEG), blood chemistry and gene expression","authors":"Kari L. Harding ,&nbsp;Emmillie Boot ,&nbsp;Jackson O. Evans ,&nbsp;Sanjay B. Shah ,&nbsp;Ramon D. Malheiros ,&nbsp;Kenneth E. Anderson","doi":"10.1016/j.japr.2025.100541","DOIUrl":"10.1016/j.japr.2025.100541","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Highly Pathogenic Avian Influenza (HPAI) outbreaks have highlighted major needs for multiple effective depopulation methods across all sectors and housing systems in the commercial poultry industry. Ventilation shutdown plus heat (VSDH), heat and relative humidity (VSDHRh), and carbon dioxide (VSDCO&lt;sub&gt;2&lt;/sub&gt;) were analyzed to understand how these methods affect broiler stress parameters and behavior. Two phases were used with both phases being conducted in sealable Plexiglass® chambers. Phase 1 (P1) analyzed electroencephalogram (EEG) of each broiler in each treatment along with blood chemistry, corticosterone, and heat shock protein 70 (HSP70) at time of death (TOD). Phase 2 (P2) looked at the progression of the stress parameters over time with specific physiological points when birds were removed from their respective chamber. There was a significant difference (P&lt;0.0001) between time of death (TOD) with VSDCO&lt;sub&gt;2&lt;/sub&gt; being significantly faster at 21.25 minutes compared to VSDH and VSDHRh at 63.75 and 58.25, respectively, in P1. However, there were no significant differences in the TOD between VSDH or VSDHRh. There was also a significant increase in chamber ending CO&lt;sub&gt;2&lt;/sub&gt;, for VSDCO&lt;sub&gt;2&lt;/sub&gt; compared to VSDH and VSDHRh. However, both VSDH and VSDHRh broilers had significantly greater (P&lt;0.0001) post core body temperatures indicating hyperthermia being the mode of action rather than hypoxia which is the mode of action in VSDCO&lt;sub&gt;2&lt;/sub&gt;. The HSP70 levels were significantly greater in VSDH at 1.23 CT&lt;sup&gt;-1&lt;/sup&gt; compared to both VSDHRh at 0.98 CT&lt;sup&gt;-1&lt;/sup&gt; and VSDCO&lt;sub&gt;2&lt;/sub&gt; at 0.90 CT&lt;sup&gt;-1&lt;/sup&gt;, which were not significantly different from each other. Blood chemistry parameters that were significantly higher in VSDCO&lt;sub&gt;2&lt;/sub&gt; treatment broilers when compared to VSDHRh were total CO&lt;sub&gt;2&lt;/sub&gt; (TCO&lt;sub&gt;2&lt;/sub&gt;), partial pressure of CO&lt;sub&gt;2&lt;/sub&gt; (pCO&lt;sub&gt;2&lt;/sub&gt;), partial pressure of oxygen (pO&lt;sub&gt;2&lt;/sub&gt;), Bicarbonate (HCO&lt;sub&gt;3),&lt;/sub&gt; and blood oxygen saturation (sO&lt;sub&gt;2&lt;/sub&gt;). When compared to VSDH, TCO&lt;sub&gt;2&lt;/sub&gt;, pCO&lt;sub&gt;2&lt;/sub&gt;, and sO&lt;sub&gt;2&lt;/sub&gt; levels were significantly greater in broilers undergoing the VSDCO&lt;sub&gt;2&lt;/sub&gt; treatment. There were also no significant differences in corticosterone between treatments in P1 with corticosterone levels for VSDH being 0.11 ng/mL, 0.10 ng/mL for VSDHRh, and 0.12 ng/mL for VSDCO&lt;sub&gt;2&lt;/sub&gt;. When analyzing the effects of these treatments on broilers over time in P2, there were no significant differences in corticosterone, blood chemistry, or HSP70 when compared within their respective treatments. Based on this research, VSDHRh may be an effective and useful depopulation method that may be used in the event of an outbreak. This is due to the equivalency of TOD in comparison to VSDH, with potential reduction in HSP70 levels. More research should be conducted on the effects of VSDHRh, especially in a non-environmentally controlled setting.&lt;/div&gt;&lt;/di","PeriodicalId":15240,"journal":{"name":"Journal of Applied Poultry Research","volume":"34 3","pages":"Article 100541"},"PeriodicalIF":1.6,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143899977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dietary lysine centered amino acid density tested across zinc levels in Ross male broilers","authors":"M.T. Kidd ,&nbsp;S.C. Wells ,&nbsp;V.G. Slick ,&nbsp;S.K. Orlowski-Workman ,&nbsp;K.B. Nelson ,&nbsp;K.M. Shafer ,&nbsp;A. Jasek","doi":"10.1016/j.japr.2025.100538","DOIUrl":"10.1016/j.japr.2025.100538","url":null,"abstract":"<div><div>Broiler nutritionists often increase amino acid density in market conditions where soybean meal price is below average, and breast meat prices are above average. Resultant diets typically have higher lysine levels, coupled with higher levels of other essential and nonessential amino acids and soybean meal. This work assessed dietary amino acid balance across organic Zn source because Zn metabolism spans all known-six enzyme classes and plays a role in protein synthesis. Ross male 708-by-product broilers were fed three Lys-driven amino acid density levels across four added Zn levels in the form of Zn Lys Zn Glu from 1 to 14, 14-28, and 28-42 d of age (12 treatments replicated 6 times). Average dietary digestible Lys ranged from below to above primary breeder guidelines and averaged Zn ranged from 0 to 60 added ppm. Intermediate and total period data consisted of live production, processing transportation weight loss, processing uniformity, processed yields, and subsequent meat quality, of which interactions were minimal, indicating the independency of dietary variables tested herein. Increasing amino acid density improved live performance and breast meat yields, but at the expense of deteriorated meat quality. Higher Zn was needed to improve early livability (1-14 d) and flock uniformity at 42 d. Regarding Lys, feeding broilers 1.30, 1.20, 1.10 % digestible of diet resulted in improved live performance whereas 1.4, 1.3, and 1.2 % digestible resulted in the highest breast yield improvements.</div></div>","PeriodicalId":15240,"journal":{"name":"Journal of Applied Poultry Research","volume":"34 2","pages":"Article 100538"},"PeriodicalIF":1.6,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143859724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}