Animal Feed Science and Technology最新文献

{"title":"Effects of a Tithonia diversifolia and Senna spectabilis extract supplement on rumen microbiota of Hair Lambs","authors":"Saira Romero-Sanchez ,&nbsp;Román David Castañeda-Serrano ,&nbsp;Carlos F. Prada Quiroga","doi":"10.1016/j.anifeedsci.2026.116635","DOIUrl":"10.1016/j.anifeedsci.2026.116635","url":null,"abstract":"<div><div>The use of natural extracts is a promising alternative to antibiotic feed additives in ruminant nutrition. Bioactive compounds such as tannins and flavonoids are known to modulate ruminal microbiota. This study evaluated the effects of a <em>Senna spectabilis</em> (SE) and <em>Tithonia diversifolia</em> (TD) extract supplemention on the rumen microbiota of Hair Lambs. Sixteen male crossbred hair lambs were randomly assigned to four treatments (n = 4): control (CG), monensin (MG), SE, and TD. Microbial diversity and composition were assessed using high-throughput 16S rRNA gene sequencing. Bacterial richness was reduced in the MG group, while SE and TD had no significant effect on overall microbial community structure (p &gt; 0.05). The rumen microbiota was dominated by Firmicutes (38.87 %), Bacteroidota (37.86 %), and Proteobacteria (17.52 %), with Prevotella as the most abundant genus (24.87 %). <em>Prevotella</em> abundance was significantly higher in MG compared to other treatments (p = 0.019), although the difference between MG (35.39 %) and SE (27.02 %) was not significant (p &gt; 0.05). <em>Ruminobacter</em> was more abundant in CG (7.30 %) and significantly lower in SE (0.78 %) (p = 0.0227). Average abundances in MG and TD were 2.26 % and 2.76 %, respectively. TD supplementation resulted in lower animal performance and limited microbial modulation. Overall, these findings provide a detailed characterization of the ruminal microbiota in hair lambs and suggest that <em>Senna spectabilis</em> extract may serve as a natural alternative to monensin for modulating rumen microbial communities and potentially improving animal productivity.</div></div>","PeriodicalId":7861,"journal":{"name":"Animal Feed Science and Technology","volume":"333 ","pages":"Article 116635"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146034386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of dietary selenium supplementation on growth performance, rumen fermentation, antioxidant profiles, and meat quality in lambs on a high-concentrate diet","authors":"Bibo Li ,&nbsp;Xiong Li ,&nbsp;Long Cheng ,&nbsp;Jiahao Li ,&nbsp;Qianqiu Liu ,&nbsp;Guoqing Duan ,&nbsp;Yining Yan ,&nbsp;Yuhang Xu ,&nbsp;Junxing Zhao ,&nbsp;Bo Wang ,&nbsp;Chunxiang Zhang","doi":"10.1016/j.anifeedsci.2025.116614","DOIUrl":"10.1016/j.anifeedsci.2025.116614","url":null,"abstract":"<div><div>High-concentrate diet feeding causes oxidative stress, alters rumen fermentation, and impairs the immune functions of lambs during fattening. Selenium (Se) is a trace element that plays a crucial role in alleviating oxidative stress. This study aimed to investigate the effects of dietary Se supplementation on growth performance, antioxidant capacity, and slaughter parameters in fattening lambs. Twenty-four 3-month-old Dorper-Hu hybrid lambs were randomly divided into two groups: a control group (CON) fed a basic diet, and a treatment group (TRT) supplemented with 0.5 mg/kg dry matter (DM) Se for 105 days. The study revealed no significant differences between the CON and TRT groups in terms of growth performance and carcass characteristics (<em>P</em> &gt; 0.05). However, the TRT group tended to have an elevated serum malondialdehyde (MDA) levels (0.05 &lt; <em>P</em> &lt; 0.1) and significantly lower serum cortisol levels (<em>P</em> &lt; 0.05). Furthermore, muscle Se concentrations, superoxide dismutase (SOD), and glutathione peroxidase (GSH-PX) were higher in the TRT group (<em>P</em> &lt; 0.05), indicating reduced oxidative stress and improved stress resistance. Ruminal fermentation parameters improved in the TRT group, with increased pH, propionate, and valerate concentrations, and reduced NH₃-N levels (<em>P</em> &lt; 0.05). Meat quality also benefited from Se supplementation, as evidenced by increased redness (a*24 h) and reduced shear force (<em>P</em> &lt; 0.05). Additionally, Se supplementation led to higher liver IgA concentrations (<em>P</em> &lt; 0.05). In conclusion, 0.5 mg/kg Se supplementation alleviates oxidative stress, modulates immune responses, and enhances lamb meat quality.</div></div>","PeriodicalId":7861,"journal":{"name":"Animal Feed Science and Technology","volume":"333 ","pages":"Article 116614"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145847601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can saturated fatty acids spare essential fatty acids in freshwater fish? Evidence from growth, metabolism and gut microbiota in common carp (Cyprinus carpio)","authors":"Yang Long ,&nbsp;Zhiyi Cheng ,&nbsp;Rui Li ,&nbsp;Zeliang Su ,&nbsp;Chaobin Qin ,&nbsp;Guoxing Nie ,&nbsp;Yuanyou Li ,&nbsp;Dizhi Xie","doi":"10.1016/j.anifeedsci.2026.116639","DOIUrl":"10.1016/j.anifeedsci.2026.116639","url":null,"abstract":"<div><div>Saturated fatty acids (SFA) are an effective energy source for fish. This study investigated whether dietary SFA can spare essential fatty acids (EFA), specifically C18 polyunsaturated fatty acids (C18 PUFA), in juvenile common carp (<em>Cyprinus carpio</em>). Four isonitrogenous (36 % crude protein) and isolipidic (9 % crude lipid) diets formulated with graded C18 PUFA/SFA ratios of 0.66 (HS, high SFA), 1.11 (BPS, balanced C18 PUFA/SFA), 1.42 (HP, high PUFA), and 2.58 (VHP, very high PUFA). Fish (initial body weight approximately 5.0 g) were reared in net cages and fed for 10 weeks. A lower dietary C18 PUFA/SFA ratio significantly improved growth performance (final body weight, weight gain rate, specific growth rate) and feed efficiency (lower feed conversion ratio), with no significant impact on survival. Most serum biochemical parameters were not significantly affected by dietary; however, aspartate aminotransferase activity was significantly lower in the BPS group than in the VHP group. Hepatic and muscular tissues in the HS group exhibited elevated levels of SFA, long-chain PUFA (LC-PUFA), and α-linolenic acid (ALA). In contrast, LC-PUFA and n-3 PUFA contents were significantly lower in the HP group than those in the HS group. Histological examination revealed lipid vacuolation and nuclear displacement in hepatocytes of HP and VHP groups. Gene expression analysis indicated that increasing dietary C18 PUFA/SFA ratios downregulated hepatic fatty acid anabolic genes (<em>acc</em>, <em>srebp-</em>1, <em>fas</em>, Δ6<em>fads2, elovl5</em>), while lipid catabolic genes (<em>cpt-I, pparα, lpl, atgl</em>) exhibite a biphasic expression pattern. Gut microbiota diversity increased with higher dietary C18 PUFA/SFA ratios, accompanied by an elevation in the relative abundance of pathogenic <em>Legionella</em> and a reduction in beneficial <em>Cetobacterium</em>. This study demonstrated that low dietary C18 PUFA/SFA ratios (≤1.11) enhance growth and lipid homeostasis in common carp, whereas higher ratios compromise hepatic health and microbiota balance. These findings provide mechanistic insights for sustainable aquafeed formulation via SFA-mediated sparing of EFA.</div></div>","PeriodicalId":7861,"journal":{"name":"Animal Feed Science and Technology","volume":"333 ","pages":"Article 116639"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145973987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Silibinin supplementation alleviates weaning stress in Holstein calves through improved growth, antioxidant response, and gut microbiota","authors":"X.L. Zhang,&nbsp;X.T. Guan,&nbsp;Y.X. Cao,&nbsp;J.X. Ma,&nbsp;D. Gnagna,&nbsp;X.J. Yin,&nbsp;Y. Li","doi":"10.1016/j.anifeedsci.2025.116620","DOIUrl":"10.1016/j.anifeedsci.2025.116620","url":null,"abstract":"<div><div>This study investigated the effects of dietary silibinin (SLB) supplementation on growth performance, immune status, stress-related plasma biomarkers, and gut microflora composition in Holstein calves. Twenty neonatal female Holstein calves (initial body weight: 42.18 ± 2.65 kg) were assigned to two dietary treatments using a randomized block design, stratified by age and weight. The control group (CON; n = 10) received a basal diet with hydroxypropyl-beta-cyclodextrin (vehicle). The experimental group (n = 10) received the basal diet supplemented with 3.25 mg SLB per kg body weight as a feed additive. During the 61-day experimental period, the calves had ad libitum access to starter feed and water while housed in individual 1.5 m³ calf pens, with rice husks used as bedding, which was replaced every two days. The calves were weaned 56 days of age. Significant improvements in growth performance, including greater final body weight, higher average daily gain, and increased dry matter intake in the pre-weaning phase, were observed with SLB supplementation. Additionally, SLB enhanced fecal scores, antioxidant status and immune function during milk feeding. Plasma analyses revealed reduced levels of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) and lipid peroxidation (malondialdehyde), alongside increased immunoglobulin levels (IgG, IgM) and total superoxide dismutase activity. Furthermore, SLB supplementation improved fecal pH and increased fecal volatile fatty acid concentration both pre- and post-weaning. Microflora analysis indicated minimal shifts in dominant phyla within the hindgut pre- and post-weaning. However, SLB supplementation increased the relative abundance of <em>Bacteroidota</em> while decreasing <em>Firmicutes</em> and <em>Actinobacteriota</em>. At the genus level, SLB increased <em>UCG-005, Lachnoclostridium</em>, <em>Prevotella</em>, and <em>Ruminococcus</em>, but decreased <em>Lactobacillus</em> and <em>Peptoclostridium</em>. Metabolomic analysis of the fecal samples indicated that SLB induced enrichment in pathways for flavonoid biosynthesis, secondary bile acid biosynthesis, and the tricarboxylic acid (TCA) cycle. It increased the production of bile acid metabolites, amino acids, and nicotinic acid, while reducing concentrations of malic acid and citric acid. These results demonstrate that SLB supplementation mitigates stress responses and deleterious effects associated with weaning by enhancing growth performance, antioxidant capacity, gut microflora composition, and intestinal health parameters in dairy calves. This study provides valuable insights into the potential application of SLB in young ruminant nutrition.</div></div>","PeriodicalId":7861,"journal":{"name":"Animal Feed Science and Technology","volume":"333 ","pages":"Article 116620"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of corn gluten meal and fermented corn gluten meal supplementation on growth and physiological responses in Holstein dairy calves","authors":"Amir Hossein Sarzaeim ,&nbsp;Mahdi Ganjkhanlou ,&nbsp;Abolfazl Zali ,&nbsp;Mehdi Dehghan Banadaky ,&nbsp;Ashkan Fekri ,&nbsp;Lucrezia Forte ,&nbsp;Valiollah Palangi ,&nbsp;Pasquale De Palo ,&nbsp;Aristide Maggiolino","doi":"10.1016/j.anifeedsci.2026.116636","DOIUrl":"10.1016/j.anifeedsci.2026.116636","url":null,"abstract":"<div><div>This study evaluated the effects of incorporating corn gluten meal (CGM) and fermented corn gluten meal (FCGM) into calf starter diets on growth performance, nutrient utilization, ruminal fermentation, feeding behavior, and blood metabolites in pre-weaned Holstein calves. Thirty calves were randomly assigned to three dietary treatments: control (CON, 100 % calf starter), CGM (5 % inclusion, replacing an equal proportion of starter on a DM basis), and FCGM (5 % inclusion, DM basis). Outcomes were monitored from day 3 to day 60 of life. Data were analyzed using mixed-model ANOVA to assess diet and time effects. Calves fed CON exhibited the highest dry matter and crude protein intake; however, calves receiving CGM and FCGM showed improved feed conversion ratios with comparable average daily gains, indicating enhanced efficiency, particularly in the FCGM group. Relative to CON, FCGM increased apparent total-tract dry matter (DM) digestibility. Ruminal fermentation profiles were modulated, with an increased acetate:propionate ratio in FCGM-fed calves. Plasma metabolite patterns were consistent with improved nitrogen utilization in the FCGM group. Feeding behavior was largely unaffected by diet. Collectively, a 5 % inclusion of FCGM in the starter improved growth efficiency and aspects of rumen function over days 3–60 of life, without compromising intake, supporting FCGM as a viable early-life nutritional strategy.</div></div>","PeriodicalId":7861,"journal":{"name":"Animal Feed Science and Technology","volume":"333 ","pages":"Article 116636"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145973988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 hydroxy methionine zinc on growth performance, digestive enzyme activity, antioxidant, and immune competence of Australian red claw crayfish (Cherax quadricarinatus)","authors":"De-Hua Kong ,&nbsp;Yu-Xiang Ji ,&nbsp;Bao-Yuan Zhang ,&nbsp;Zi-Yan Liao ,&nbsp;Jing-Xiang Zhou ,&nbsp;Qiu-Ju Wang","doi":"10.1016/j.anifeedsci.2025.116624","DOIUrl":"10.1016/j.anifeedsci.2025.116624","url":null,"abstract":"<div><div>Zinc is an essential trace element in living organisms, which is recognized as the “life element”, hydroxy methionine zinc (Zn-MHA), as a fourth-generation zinc product, exhibits advantages such as well-defined and stable structure, easy absorption, and broad application potential in aquatic species. The current study assesses the efficacy of Zn-MHA in <em>Cherax quadricarinatus</em>. This breeding experiment was conducted in the greenhouse of Gongzhuling Rice and Fishing Base, Jilin Province, China. Five experimental diets were formulated by supplementing a basal diet with 0 (control, C0), 15 (Z1), 30 (Z2), 60 (Z3), and 90 (Z4) mg kg⁻¹ of Zn-MHA. Crayfish with an initial body mass of 0.50 ± 0.01 g were selected and fed for 8 weeks. The experimental results show that the group fed the zinc-free diet exhibited inferior growth performance, digestive enzyme activity, and antioxidant and immune-related indices compared to the zinc-supplemented groups. These results indicate that dietary Zn-MHA supplementation at 15–90 mg kg⁻¹ promotes growth, improves digestive function, and enhances antioxidant and immune capacities in red claw crayfish. Under the experimental conditions, the optimal dosage was determined to be 60 mg kg⁻¹. This can providing a scientific basis for its rational application in feed formulations.</div></div>","PeriodicalId":7861,"journal":{"name":"Animal Feed Science and Technology","volume":"333 ","pages":"Article 116624"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 soybean isoflavones modulate reproductive hormones and immunity by altering rumen microbiota in ewes","authors":"Mengqi Lou ,&nbsp;Xiongxiong Li ,&nbsp;Shengguo Zhao ,&nbsp;Jinlong Xu ,&nbsp;Qingshan Fan ,&nbsp;Yuzhu Sha ,&nbsp;Jie Bai ,&nbsp;Ting Jiao","doi":"10.1016/j.anifeedsci.2025.116618","DOIUrl":"10.1016/j.anifeedsci.2025.116618","url":null,"abstract":"<div><div>Soybean isoflavones may improve reproductive performance in ruminants by modulating rumen microbiota. We hypothesized that dietary soybean isoflavone (SI) supplementation would alter reproductive hormone profiles, antioxidant capacity, and immunity in ewes through rumen microbial alterations. Twenty Hu sheep ewes (1.5 months old; 17.82 ± 0.98 kg BW) received either a basal diet (CON) or a basal diet + 30 mg SI/kg BW throughout estrus (the day after completion of estrus synchronization treatment), pregnancy (on day 120 of gestation, with all ewes confirmed pregnant), and lactation (on day 30 of postpartum). The reproductive performance of the ewes was recorded, and the body weight of newborn lambs was measured at 15 - day intervals. Ewes blood and rumen fluid samples were analyzed for hormones, antioxidants, immune parameters, fermentation products, and microbial diversity via 16S rRNA sequencing. Although no significant changes were observed on ewes reproductive performance and the newborn lambs birth weight, SI supplementation increased (<em>P</em> &lt; 0.05) reproductive hormones (E2, FSH, LH, P4) across most reproductive stages compared with CON. Antioxidant enzymes (GSH-Px, CAT) increased (<em>P</em> &lt; 0.05) while malondialdehyde decreased during critical periods. Immunoglobulins (IgA, IgG, IgM) were enhanced (<em>P</em> &lt; 0.05) throughout the reproductive cycle. SI increased ruminal acetate and propionate during lactation and altered microbial composition, reducing the abundance of <em>unclassified_Clostridia</em> and <em>Lachnospiraceae_XPB_1014_group</em> during lactation (<em>P</em> &lt; 0.05). Correlation analysis revealed significant associations between altered microbial genera and improved physiological parameters. The results indicate that SI supplementation can modulate reproductive hormones profiles in ewes, enhance antioxidant defense capacity and immune function by modulating rumen microbiota, supporting its application as a natural feed additive in sheep farming.</div></div>","PeriodicalId":7861,"journal":{"name":"Animal Feed Science and Technology","volume":"333 ","pages":"Article 116618"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Economic and productive impacts of dietary turnip (Brassica rapa) leaf powder on Nile tilapia (Oreochromis niloticus) fingerlings","authors":"Samia Fawzy ,&nbsp;Sara Mohammed ,&nbsp;Haitham G. Abo-Al-Ela ,&nbsp;Mohamed A. Helal ,&nbsp;Seham El-Kassas","doi":"10.1016/j.anifeedsci.2025.116622","DOIUrl":"10.1016/j.anifeedsci.2025.116622","url":null,"abstract":"<div><div>The present study investigated the impact of the dietary inclusion of dried turnip leaf (DTL) powder on growth performance, hematological and immunological parameters, serum biochemistry, antioxidant and digestive enzyme activity, gut health and economic efficiency indices in mono-sex Nile tilapia. A total of 225 mono-sex Nile tilapia (<em>Oreochromis niloticus</em>) with an average weight of 2.13 ± 0.5 g were randomly assigned to five treatments, with three replicates each resulting in 15 glass aquaria (each containing 15 fingerlings). The DTL powder was included at 0, 2, 4, 6, and 8 % of the diet for DTL0, DTL2, DTL4, DTL6, and DTL8, respectively, and the experiment lasted for 65 days. The chemical analysis of DTL revealed several compounds, with <em>p</em>-coumaric acid, ferulic acid, chlorogenic acid, and caffeic acid present at the highest levels. The results revealed a significant improvement in Nile tilapia growth performance and feed utilization, as confirmed by increases in final weight, body weight gain, SGR, and PER and improvements in FCR, with a peak of 6 % DTL. The improved growth performance was correlated with enhanced gut health manifested by improved intestinal histomorphological features, reducing the total bacterial count with a favorable shift to beneficial <em>Lactobacillus</em> (<em>P</em> &lt; 0.05). Furthermore, the dietary inclusion of DTL powder markedly increased hematological indices (<em>P</em> &lt; 0.05), including the levels of antioxidants (SOD and CAT), accompanied by a reduction in the phagocytic activity of MDA and lysozyme activity without altering the serum lipid profile (<em>P</em> &lt; 0.001). Profitability and economic efficiency were also enhanced in all the DTL-containing groups, peaking at 6 % DTL (<em>P</em> ≤ 0.001). Therefore, the dietary incorporation of up to 6 % DTL powder could be a cost-effective alternative feed ingredient to increase the growth, feed utilization, general health, and immunity of Nile tilapia.</div></div>","PeriodicalId":7861,"journal":{"name":"Animal Feed Science and Technology","volume":"333 ","pages":"Article 116622"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of a simplified in vitro method to estimate the rumen protein degradation","authors":"Gonzalo Fernández-Turren ,&nbsp;Claudio Antonio Pozo ,&nbsp;José Luis Repetto ,&nbsp;Cecilia Cajarville ,&nbsp;Gilberto Vilmar Kozloski","doi":"10.1016/j.anifeedsci.2026.116634","DOIUrl":"10.1016/j.anifeedsci.2026.116634","url":null,"abstract":"<div><div>This study aimed to evaluate the reliability of a simplified method to estimate the ruminal degradability of crude protein (CP), based on ammonia N release <em>in vitro</em>, compared to the <em>in situ</em> conventional method. Two preliminary trials were conducted to evaluate the dynamics of ammonia N production and uptake by rumen microorganisms and its relationship with gas and purine bases (PB) accumulation <em>in vitro</em> as an indicator of microbial biomass. In Trial 1, starch, cellulose and casein samples were incubated and gas production and both ammonia N and PB accumulation were measured. No significant correlation was found between gas, ammonia N and PB accumulation. In Trial 2, casein and soybean meal samples were incubated with rumen inoculum added with 10 mg/L of (¹⁵NH₄)₂SO₄ and gas production, ammonia N accumulation and ¹⁵N concentration in the incubation medium were measured. Ammonia N uptake represented only 6 % of the total ammonia N released throughout the 48 h of fermentation of casein or soybean meal. The ¹⁵N concentration drastically decreased up to 24 h of incubation. Trial 3 evaluated whether the <em>in vitro</em> CP degradation parameters of ten moderate to high-protein feedstuffs were related to those obtained by the <em>in situ</em> conventional method. There was a positive linear relationship (<em>P</em> &lt; 0.05) between methods for estimating the potentially degradable CP (R² ≥ 0.80) and the fractional rate of CP degradation (<em>kd</em>; R² = 0.56), with the <em>in vitro kd</em> being, on average, 66 % lower than the <em>in situ.</em> Effective CP degradability (ECPD) of feedstuffs estimated in both methods was positively related (R² = 0.93; <em>P</em> &lt; 0.05). The simplified method based on ammonia N release <em>in vitro</em>, without correction for ammonia N uptake by microorganisms, may be used to estimate the extent or ruminal protein degradation of feedstuffs with moderate to high CP content.</div></div>","PeriodicalId":7861,"journal":{"name":"Animal Feed Science and Technology","volume":"333 ","pages":"Article 116634"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145973992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 effect of a water-based delivery of an Ascophyllum nodosum extract on animal performance, rumen microbiota, fermentation, and methane emissions of zero-grazed beef steers","authors":"Aaron Casey ,&nbsp;Tommy M. Boland ,&nbsp;Alan K. Kelly ,&nbsp;Zoe C. McKay ,&nbsp;Fionnuala Godwin ,&nbsp;Maria Markiewicz-Keszycka ,&nbsp;Marco Garcia-Vaquero ,&nbsp;Calum Bridson ,&nbsp;Padraig Hennessy ,&nbsp;Sivaprakash Balakrishnan ,&nbsp;Kieran J. Guinan ,&nbsp;John T. O’Sullivan ,&nbsp;Stafford Vigors","doi":"10.1016/j.anifeedsci.2026.116632","DOIUrl":"10.1016/j.anifeedsci.2026.116632","url":null,"abstract":"<div><div>This study evaluated the effects of an <em>Ascophyllum nodosum</em> (ASC) extract delivered via a water-based system on animal performance, rumen microbiota, fermentation, and methane (CH₄) emissions in beef steers. Thirty dairy-beef steers were randomly allocated to one of two dietary treatments (<em>n</em> = 15) for a 70-d period. Treatments consisted of either <em>ad libitum</em> zero-grazed grass (<strong>CTR</strong>; no extract) or <em>ad libitum</em> zero-grazed grass plus an ASC extract (<strong>ASCE</strong>) supplemented at 1.5 % of dry matter intake (DMI), administered via a water-based system. Additionally, all steers were offered a maximum of 1.4 kg/d of concentrate. Methane was measured throughout the study using the GreenFeed emissions monitoring system (GEM). A feed intake estimation period was conducted during week 5 and 10, while rumen fluid samples were collected on d-33 and d-68 for rumen microbiota and fermentation analysis. There was no difference between treatments for total DMI, average daily gain (ADG), or diet digestibility. Methane production was similar between treatments, averaging 206.6 g/d for CTR and 204.6 g/d for ASCE. Methane yield (g/kg DMI) and intensity (g/kg ADG) were also unaffected, averaging 24.8 g/kg DMI and 130.8 g/kg ADG, respectively. The proportion of butyrate was lower, and ammonia-nitrogen (NH₃-N) concentration was higher in ASCE-treated steers. Microbial abundances were unaffected, with <em>Bacteroidota</em> (51 %) and <em>Firmicutes</em> (38.3 %) being the most abundant phyla across both treatments. In conclusion, ASCE supplementation did not impact animal performance, CH₄ emissions or rumen microbiota.</div></div>","PeriodicalId":7861,"journal":{"name":"Animal Feed Science and Technology","volume":"333 ","pages":"Article 116632"},"PeriodicalIF":2.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}