Search Results (932)

Dactylis glomerata, a perennial forage grass widely distributed in Mediterranean areas, is recognized for its adaptability and nutritional quality. This study aimed to assess the chemical composition and fiber components of ten natural populations of Dactylis glomerata in order to characterize genetic variability in nutritional and fiber traits among populations. Seeds of all populations were established in a randomized complete block design with four replicates and cultivated for two consecutive years. Forage was collected at the boot stage, and analyses were conducted for crude protein, ash, crude fiber, neutral and acid detergent fibers, acid detergent lignin, hemicellulose, cellulose, digestible dry matter, dry matter intake, and relative feed value. Combined ANOVA indicated that genotypic effects were highly significant for all traits (p ≤ 0.001), with additional significant contributions from environmental and genotype × environment interactions. Crude protein ranged from 11.74% to 14.98%, neutral detergent fiber from 56.31% to 58.43%, and relative feed value from 100.1 to 106.4 among populations. Stability index analysis identified Kefalopotamos and Filyra as the most environmentally stable populations, whereas Kori and Xyloparoiko exhibited relatively higher values in selected forage quality traits. Broad-sense heritability values were high for the majority of traits (H² between 93.3% and 99.9%, except for hemicellulose), suggesting a strong genetic influence. Correlation analysis also revealed inverse relationships between protein content and fiber fractions and positive relationships with digestibility-related indices. Multivariate analyses revealed a clear separation between nutritional quality traits and structural fiber components, indicating consistent differentiation among populations. Overall, these results highlight the potential of local Dactylis glomerata populations as genetic resources for further evaluation in breeding and conservation programs under Mediterranean conditions. Full article

This study investigated the effects of different inclusion levels of defatted black soldier fly (Hermetia illucens: BSF) larval meal on growth performance, haematological and biochemical blood parameters, and nutrient digestibility in piglets. Forty-eight male piglets weaned at 28 days of age ((Landrace × Large White) × (Piétrain)) were randomly assigned to three experimental treatments. Each treatment included eight pens with two piglets per pen. Diets were formulated to be isoenergetic and isoproteic, containing defatted BSF meal as a partial replacement for fishmeal and soybean meal: Control (0% BSF), BSF3% (3% inclusion), and BSF6% (6% inclusion). Over the whole experimental period, dietary treatment did not significantly affect final body weight, average daily gain, average daily feed intake, or feed conversion ratio, although feed intake differed during the 7–28-day period. Red and white blood cell parameters were not influenced by diet. Apparent total tract digestibility of dry matter and organic matter increased at the 6% inclusion level, while crude protein and crude fat digestibility were not affected. These results indicate that defatted BSF meal can be used as a sustainable alternative protein source in piglet diets, maintaining growth performance and health status. Full article

Winter feeding represents a significant cost in beef production, requiring efficient strategies that maintain productivity while minimizing environmental impact. Forty-six pregnant cows (620 ± 61 kg BW) were used to evaluate an ad libitum hay-based diet (2.02 Mcal/kg ME; HFOR; n = 23) versus a corn-based diet (2.84 Mcal/kg ME) limit-fed at 1.2% BW (HCON; n = 23) from 50 d pre-calving to 84 d post-calving. Pre- and post-calving, HCON cows consumed less (p < 0.01) dry matter, crude protein, and water than HFOR cows. While CH₄ yield per kg DMI was greater (p < 0.01) for HCON cows, total daily CH₄ emissions and CH₄ per unit of NEm intake were lower (p ≤ 0.03) compared with HFOR cows. Behavioral data showed that HCON cows had fewer (p < 0.01) meals and spent less time eating, but had greater intake per minute. Cow BW differed by treatment over time (p < 0.01), with HCON cows weighing less through early lactation, though no differences were observed from d 84 to weaning. Calf BW remained unaffected (p ≥ 0.76). In conclusion, limit-feeding a corn-based diet improves feed and water use efficiency and reduces enteric CH₄ emissions without compromising calf growth, offering a viable alternative to traditional forage-based wintering systems. Full article

Yaks (Bos grunniens) on the Qinghai–Tibetan Plateau face severe nutritional limitations during the dry season due to dependence on highly lignified, low-quality roughage. Identifying safe and effective rumen regulators capable of enhancing fiber utilization in this species is therefore of great practical importance. This study employed a two-pronged approach integrating in vitro mechanistic investigation and in vivo validation to evaluate the effects of the amphoteric surfactant cocamidopropyl betaine (CAPB) on rumen fermentation, the micro-spatial distribution of digestive enzymes, apparent total tract digestibility, and the macroscopic growth performance of yaks. In the in vitro fermentation trial (Experiment 1), a randomized block design was employed where a straw-based high-forage diet was used as the substrate and supplemented with 0, 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0% CAPB (based on substrate dry matter, DM) for a 48 h batch culture. The results showed that as the CAPB supplementation level increased, cumulative gas production, the degradation rates of DM and neutral detergent fiber (NDF), and the yields of total volatile fatty acids and microbial protein all exhibited significant quadratic responses (p < 0.05), peaking at the 0.5–1.0% supplementation levels. Concurrently, CAPB significantly promoted the transfer and release of carboxymethyl cellulase and xylanase into the free liquid phase (p < 0.01). In the in vivo validation trial (Experiment 2), 24 healthy growing male yaks (initial body weight 131.2 ± 8.4 kg) were allocated in a completely randomized design to four groups and fed a basal diet supplemented with 0, 0.5, 1.0, or 2.0% CAPB for 44 days. The results indicated that, while maintaining a stable DM intake, the addition of 0.5% CAPB significantly increased the average daily gain (ADG) of yaks (p < 0.05), improved the feed-to-gain ratio, and significantly enhanced the apparent total tract digestibility of NDF and ether extract (p < 0.05). However, when the supplementation dose exceeded the safety threshold (≥2.5% in vitro and ≥2.0% in vivo), both fermentation parameters and growth advantages declined. In conclusion, under the present experimental conditions, 0.5% CAPB improved roughage fermentation efficiency, putatively through an ‘enzyme elution’ mechanism, and was associated with macroscopic improvements in NDF and EE apparent digestibility and ADG in growing yaks. These findings identify 0.5% CAPB as a promising candidate rumen regulator for improving roughage utilization in growing yaks; broader generalization will require larger-scale and longer-duration trials. Full article

The objective of this study was to evaluate the effects of dietary inclusion of increasing levels of soybean oil on milk yield, milk composition, and milk fatty acid profile in dairy cows. The experiment was designed as a 4 × 4 double Latin square with 21-day periods and used eight Holstein cows (body weight of 550 ± 19.5 kg and 200 ± 5 days in milk). The treatments evaluated were a basal diet without soybean oil and a basal diet added with 10, 20, or 30 g/kg DM of soybean oil. None of the treatments evaluated affected (p > 0.05) milk yield, dry matter intake, dry matter digestibility, or the concentration of fat, non-fat solids, protein, and lactose in milk. Furthermore, increasing levels of soybean oil included in the diets did not affect (p > 0.05) the milk concentration of butyric, caproic, caprylic, capric, lauric, pentadecanoic, palmitoleic, heptadecanoic, and linoleic fatty acids. However, dietary inclusion of soybean oil decreased (linear effect; p ≤ 0.05) the milk concentration of myristic, palmitic and oleic fatty acids. In contrast, higher concentrations (linear effect; p ≤ 0.05) of stearic fatty acids were observed in the milk of dairy cows fed soybean oil in their diet. In conclusion, dietary inclusion of increasing levels of soybean oil (30 g/kg DM) modifies the fatty acid profile of milk without affecting milk yield or the protein, fat, or lactose content. Full article

This study investigated the replacement of squid-liver powder (SLP) with different marine protein hydrolysates in diets for Pacific white shrimp (Litopenaeus vannamei) over an eight-week feeding period. A control diet contained 5% SLP, whereas four test diets replaced 1% of the diet (dry-matter basis) with tuna hydrolysate liquid (TH), shrimp hydrolysate powder (SH), fish hydrolysate powder (FH), or salmon silage liquid (SS), with soybean meal adjusted to maintain dietary protein balance. Shrimp fed the TH diet showed higher final body weight (15.76 ± 0.24 g shrimp⁻¹) and specific growth rate (3.18 ± 0.02% day⁻¹) than those fed the other experimental diets (p < 0.05). TH also increased feed intake (20.96 ± 0.49 g shrimp⁻¹) and was associated with higher trypsin activity (3236 ± 226 unit h⁻¹ mg protein⁻¹) and improved protein digestibility. Histological observations indicated greater hepatopancreatic cell density and increased intestinal villus height in the TH group. In addition, survival of shrimp fed TH (90.0 ± 2.8%) was higher than that observed in the FH and SS groups (p < 0.05), and hemolymph from TH-fed shrimp showed stronger inhibitory activity against Vibrio parahaemolyticus. Overall, among the evaluated hydrolysates, 1% tuna hydrolysate (dry-matter basis) produced the most consistent improvements across growth performance, digestive capacity, and selected health-related indicators, supporting its feasibility as a partial substitute for squid liver powder in shrimp diets. Full article

This study evaluated the effects of replacing soybean meal with cashew nut roasting residue (CNRR) on feed intake, nutrient digestibility, rumen fermentation, blood metabolites, and economic efficiency in lactating crossbred Saanen goats. Fifteen does were assigned to a completely randomized design with three treatments: 0% CNRR (T1), 10% replacement of soybean meal protein (T2), and 20% replacement (T3). Goats were fed pangola hay ad libitum and concentrate according to milk yield (1:2). Total dry matter, organic matter, crude protein, and fiber intake were not affected by dietary treatments (p > 0.05). However, crude protein digestibility decreased from 68.83% in the control group to 52.72% and 51.21% in the CNRR treatments (p < 0.05). Rumen pH and total volatile fatty acids remained within normal physiological ranges, suggesting stable rumen fermentation. Blood parameters, including packed cell volume, glucose, and blood urea nitrogen, were not influenced by CNRR supplementation (p > 0.05). Economic analysis showed reduced feed cost with increasing CNRR inclusion. In conclusion, CNRR can replace soybean meal protein at rates of up to 20% without affecting feed intake, ruminal pH, or measured blood metabolites; however, crude protein digestibility was reduced, indicating that dietary formulation may require adjustment. Full article

This study aimed to investigate the impact of dietary L-citrulline supplementation on the health of mares during late gestation. Thirty-two healthy mares in late pregnancy were randomly assigned to four groups: a control group (CON, 0 g/d) and three treatment groups receiving 15, 30, and 45 g/d/head of L-citrulline, respectively. The trial spanned 72 days, including a 12-day adaptation phase and a 60-day formal feeding period. A fixed daily feeding amount of 11.2 kg/head was provided, ensuring complete consumption and consistent dry matter intake across all groups. Results demonstrated that supplementation with 30 g/d/head of L-citrulline significantly improved the apparent digestibility of crude protein and nitrogen metabolism rate (p < 0.05), while notably increasing plasma superoxide dismutase (SOD) activity (p < 0.01) and reducing plasma malondialdehyde (MDA) concentration by 10.53% (p < 0.01). Furthermore, mares receiving 30 g/d of L-citrulline showed a 14.81% increase in plasma estradiol (E2) concentration (p < 0.01). Urinary concentrations of E2, estrone sulfate (ESS), and 17α-dihydroequilin sulfate (17α-DHEQS) were also significantly elevated (p < 0.05). This supplementation also enhanced plasma amino acid levels related to the urea cycle and improved the diversity of fecal microbiota, increasing the abundance of beneficial bacteria. A multi-indicator scoring system identified 30 g/d as the optimal supplemental dose of L-citrulline. These findings suggest that 30 g/d of L-citrulline may act as a nutritional regulator, offering valuable insights for enhancing the physiological and metabolic health of mares during late gestation. Full article

The objective of this study was to evaluate the productive performance, ruminal fermentation, in vivo digestibility, carcass yield, and physicochemical variables of meat when bovine rumen content (BRC) was included in the diet of lambs. Thirty-six Pelibuey-Dorper crossbred lambs of both sexes, with an average weight of 19.5 ± 1.5 kg, were used in a generalized randomized block design with the sex of the lambs as a blocking factor with four treatments: BRC₀, BRC₁₅, BRC₃₀, and BRC₄₅, corresponding to 0%, 15%, 30%, and 45% BRC inclusion in the diet, respectively. The results indicate that the dietary effect was not significant for any of the evaluated variables, whereas sex showed significant differences in final body weight, average daily gain, dry matter intake, and hot and cold carcass yield. Although specific treatment-sex combinations significantly influenced productive performance variables such as average daily gain, dry matter intake and ruminal fermentation parameters, such as propionic acid, there is no consistent evidence that the inclusion of bovine rumen content promotes superior productive performance or carcass quality in fattening lambs. Full article

The attraction of neonatal piglets to sow feces and their coprophagy suggests that fecal semiochemicals promote nutrient intake and gut colonization, but their microbial origin is poorly understood. This study explored associations between gut microbiota and fecal semiochemical/metabolic profiles in prepartum and postpartum sows. Fecal samples were collected from six crossbred sows at 4 days prepartum and 3 days postpartum. Nutritional components, volatile organic compounds (VOCs), untargeted metabolomics, and gut microbiota were analyzed. Nutritional composition remained largely stable postpartum, except that sodium increased while potassium, magnesium, and cellulose decreased. Skatole and p-cresol concentrations increased postpartum even after dry matter correction. Untargeted metabolomics identified 298 differentially abundant metabolites (250 up, 48 down) postpartum, enriched in nicotinamide/nicotinate metabolism, arginine biosynthesis, and others. Gut microbial alpha diversity (Shannon, Chao1, observed features) decreased postpartum. Fibrolytic and butyrate-producing bacteria (e.g., Ruminococcaceae UCG-005, Lachnospira) were enriched prepartum, whereas Escherichia-Shigella, Christensenellaceae R-7 group and Enterococcus were more abundant postpartum. Spearman correlations showed skatole and p-cresol were strongly negatively correlated with butyrate-producing bacteria and positively correlated with postpartum-enriched genera. This study uncovered prepartum-to-postpartum shifts in sow fecal components and microbiota, revealing a microbial basis for semiochemical production and offering probiotic insights using coprophagy to improve piglet health. Full article

This study evaluated the effects of sodium monensin or a blend containing condensed tannins and yeast products on intake, digestibility, performance, and methane emissions in lactating Holstein cows. Nine cows (three rumen-fistulated and six non-fistulated) were assigned to three 3 × 3 Latin squares. The treatments were: a control (CON), sodium monensin (MON; 12 mg/kg of dry matter [DM]), condensed Acacia tannins and Saccharomyces cerevisiae yeast blend (SUP; 2 g/kg of DM). The trial lasted 84 days, with three 28-day periods. Neutral detergent fiber (NDF) intake was higher in CON and SUP (p = 0.029). Milk yield, energy-corrected milk, and milk composition did not differ (p > 0.05). The total methane emissions were not affected by treatments (p > 0.05). Methane yield/Kg of DM intake (DMI), organic matter intake (OMI), and digestible OM tended to be lower in SUP (p = 0.091, p = 0.093, p = 0.086). SUP increased the DM, crude protein (CP), and NDF ingestion rates (p = 0.049, p = 0.028, p = 0.013) and decreased the CP rumen pool (p = 0.014). Rumen pH tended to be higher in SUP (p = 0.067). The potentially digestible NDF digestion rate decreased in MON (p = 0.007). Finally, SUP-treated animals showed a tendency to reduce their methane yield relative to DMI, OMI, and digestible OM. Further studies should investigate the long-term impacts of supplementation, rumen microbiome changes, and underlying mechanisms driving methane mitigation. Full article

Several studies have shown that supplementation with 100 to 130 mg of 3-nitrooxypropanol (3-NOP)/kg diet acts as a mitigating factor of enteric CH₄ production in ruminants. From an energy perspective, this effect could indicate improved feed energy utilization. Feed additives that reduce the acetate-to-propionate molar ratio and/or CH₄ production generally increase the efficiency of feed energy utilization and can alleviate the negative impact of high ambient heat loads on ruminant productivity. In seeking to test this assumption, the impact of supplementing 3-NOP in growing–finishing diets was evaluated in 24 intact male lambs (31.92 ± 3.77 kg). The experiment lasted 61 days. Treatments consisted of supplementing a total mixed growing–finishing diet (30:70 forage-to-concentrate ratio) with zero or 115 mg 3-NOP/kg diet. Lambs were assigned to 12 pens (two lambs/pen, six replicates per treatment). The temperature–humidity index (THI) during the experiment averaged 83.37 ± 6.4. The inclusion of 3-NOP tended to increase final weight (2.6%, p = 0.06) but increased dry matter intake by 10.6% (p = 0.03), thus decreasing the efficiency of dietary net energy utilization by 2.3% and 3%, respectively (p = 0.04). Lambs fed with 3-NOP showed greater (6.2%, p = 0.04) carcass weight and dressing percentage (3.3%, p = 0.03) without effects on the tissue shoulder composition. Supplemented lambs showed lower gastrointestinal (GIT) fill (9.3%, p = 0.02) and greater (1.3%) empty body weight (EBW, p < 0.01). Visceral organ mass (expressed as g/kg EBW) was not affected by 3-NOP supplementation. It was concluded that supplemental 3-NOP did not improve feed efficiency nor the efficiency of dietary energy utilization, but did improve carcass weight and dressing percentage in lambs fattened under high ambient heat load. The greater carcass weight observed in the present experiment was due mainly to a tendency for a greater final weight (p = 0.06) for 3-NOP lambs, whereas the improvement in dressing percentage was due mainly to a lower (p = 0.02) GIT fill. It is crucial to highlight that this is a pioneering study on the effect of 3-NOP on the productive efficiency of lambs subjected to high ambient heat loads. It is also important to note that enteric methane production was not measured in this experiment. Although the doses used in this experiment have consistently reduced methane production in several studies conducted under favorable climatic conditions, we cannot precisely determine the role of CH₄ production in the dietary net energy efficiency observed in lambs that received 3-NOP. The results presented here provide a basis for future research evaluating the anti-methanogenic and productive responses to the use of 3-NOP under high ambient temperature conditions. Full article

The objective of this study was to assess the contribution of oat (Avena sativa L.) and common vetch (Vicia sativa) hay supplementation as a forage-based strategy to improve the environmental and productive performance of grazing systems in the high Andean zone through its effects on enteric methane (CH₄) emissions and live weight gain. Twenty heifers grazed native grasses, and only half of the group received the supplement. The experiment was conducted as a crossover design. Methane emissions were quantified through sulfur hexafluoride methodology. Native pastures were characterized by low protein content, while lignin was lower in the oat hay plus common vetch hay than in the native grass mixture. On average, heifers consumed 7 kg dry matter per day (p ≥ 0.05) and ingested 24% more crude protein when supplemented (p = 0.0001). Digestible and metabolizable energy intakes were also significantly higher in supplemented animals (p ≤ 0.05). Live weight change was positive for supplemented animals (245 g/d). Net CH₄ production ranged from 179.6 to 196.3 g/d (p = 0.183). However, when CH₄ emissions were expressed relative to crude protein or acid detergent lignin intake, supplemented diets were found to emit less than native grass-based diets (p ≤ 0.05). These results suggest that supplementation with oat hay plus vetch is a feeding alternative for heifers during the dry season in the Peruvian Andean region to increase animal productivity without affecting CH₄ emissions. Full article

The objective of this study was to investigate the effects of supplemental starter feeding on the development of the ruminal epithelium in suckling yak calves using transcriptomic analysis. Twenty healthy one-month-old male yak calves with similar body weights were selected and randomly assigned to two groups. The pre-feeding adaptation period lasted 14 days, followed by a 120-day experimental feeding period. At the end of the trial, five calves from each group were slaughtered, and samples of abomasum tissue and ruminal contents were collected for subsequent analyses. The results demonstrated that early concentrate supplementation markedly increased the final body weight and ruminal NH₃-N concentration of calves in the RAS group compared with the control (RA) group (p < 0.05). Similarly, dry matter intake and ruminal microbial protein (MCP) content were significantly higher in the RAS group (p < 0.05). In contrast, the concentration of acetic acid in ruminal fluid was significantly higher in the RA group, whereas valeric acid concentration was higher in the RAS group. Furthermore, ruminal TNF-α, TNF-γ, and IL-2 concentrations were significantly elevated in the RAS group (p < 0.05), suggesting enhanced ruminal immune function. Transcriptomic analysis revealed that both up- and down-regulated gene expression contributed to the morphological development and overall health of the ruminal epithelium. Up-regulated genes were enriched in pathways related to chemical carcinogenesis, cytochrome P450 metabolism, steroid hormone biosynthesis, retinol metabolism, ascorbate and aldarate metabolism, drug metabolism-cytochrome P450, pentose and glucuronate interconversions, ovarian steroidogenesis, and porphyrin and chlorophyll metabolism. Conversely, down-regulated genes were mainly associated with cytokine–cytokine receptor interactions, mineral absorption, arachidonic acid metabolism, and viral protein interactions with cytokine receptors. Overall, early supplementation with concentrate feed enhanced the expression of genes associated with ruminal epithelial development, improved immune responses, and promoted better growth performance in suckling yak calves. Full article

Crude glycerin (CG) is an energy-dense ingredient capable of partially or fully replacing corn in high-concentrate diets for ruminants. Its rapid ruminal absorption, favorable fermentative profile, and absence of lactic acid production may support safer adaptation to intensive feeding systems. The aim of this study was to evaluate the effects of replacing corn with CG (300 g/kg DM) on growth performance, feeding behavior, rumen morphometry, and proteomic responses of ruminal papillae in feedlot lambs. Sixty-five Santa Inês × Dorper lambs were assigned to either a control diet or a diet containing CG and were evaluated during pre-adaptation, adaptation, and finishing phases. Replacing corn with CG slightly reduced average daily gain (p = 0.02), without affecting final body weight, dry matter intake, or carcass yield (p > 0.05). Lambs fed CG exhibited lower subcutaneous fat thickness (p = 0.04) and reduced neutral detergent fiber intake during feeding behavior assessments (p < 0.05). Rumen papillae showed higher mitotic index and greater epithelial activity throughout the feedlot period, regardless of treatment. Proteomic analysis revealed upregulation of proteins involved in epithelial integrity (Claudin-1, Occludin) and mitochondrial energy metabolism (ATP synthase β, glycerol kinase) in CG-fed lambs, alongside downregulation of proteins related to oxidative stress and inflammation (HSP70, Annexin A1, SOD1, Peroxiredoxin-6). These findings demonstrate that CG promotes beneficial molecular adaptations in the ruminal epithelium without compromising carcass traits, supporting its use as a safe, functional, and sustainable alternative to corn in lamb finishing systems. Full article