Search Results (65)

In this study, eight treatment groups were set up with three replicates in each group to investigate the effects of Bacillus, Lactobacillus, and molasses on the chemical composition and fermentation quality of fermented rice straw. Furthermore, an animal experiment was conducted to determine the nutrition apparent digestibility, ruminal fermentation characteristics, and methane emission in Hu sheep. The results showed that the dry matter (DM) and crude protein (CP) content in the group treated with Bacillus megaterium and Lactobacillus acidophilus (BMLB) was significantly higher than that in the group with no additive (CK) (p < 0.05). Compared with the CK group, all treatments with single or composite addition of Bacillus significantly reduced the content of neutral detergent fiber (NDF) and acid detergent fiber (ADF) (p < 0.05). The content of acetate, propionate, and NH₃-N in the BMLB group were significantly lower than those in the CK group (p < 0.05). In addition, the Hu sheep in the BMLB group showed a significant reduction in daily methane emission per unit of metabolic body weight. In conclusion, the BMLB treatment significantly improved the nutritional value, fermentation quality, ruminal fermentation, and methane emission of rice straw haylage in Hu sheep. Full article

Saline–alkaline soils are increasingly reducing global forage productivity and may indirectly compromise the nutritional quality of animal-derived foods for human consumption. Alfalfa, grown under saline–alkaline conditions, often accumulates sodium, thereby altering its nutritional composition and digestibility. NaCl was added to an alfalfa-based total mixed ration (TMR) to model saline-alkaline alfalfa with high salt content. This method is a simplified modeling approach wherein sodium chloride is used to simulate saline stress. We have studied, using this model, changes in growth performance, nutrient digestibility, amino acid composition, and meat quality of AOHU (Hu × Australian White) lambs. The levels of dietary NaCl were set at 0.43% (to reflect the baseline NaCl content of standard alfalfa-based TMR and 1.71% (to reflect a level of high-salt alfalfa produced under saline–alkaline growing conditions). Compared to the control group, supplementation with NaCl enhanced the average daily gain, feed conversion efficiency, relative growth rate, and dry matter intake (p < 0.05). Apparent digestibility of dry matter, organic matter, crude protein, ether extract, fiber fractions (NDF and ADF), and gross energy was also improved (p < 0.001), reflecting enhanced nutrient utilization. Total saturated fatty acids had decreased, while meat redness increased, and the PUFA/SFA ratio increased, reflecting a leaner and healthier lipid profile. Moreover, essential amino acids-threonine, valine, methionine, isoleucine, leucine, and lysine-were significantly higher (p < 0.05), revealing a better meat nutritional quality. In summary, dietary NaCl supplementation in an alfalfa-based TMR effectively simulates saline–alkaline conditions that improve growth performance, nutrient digestibility, and meat nutritional composition. Results from this study show how NaCl supplementation in alfalfa-based rations—used here to mimic the elevated salt levels found in alfalfa grown on saline–alkaline soils—affects growth performance, nutrient digestibility, and meat quality in lambs, providing insight for feeding strategies in salt-affected production systems. Full article

This study investigated the effects of supplementing rumen-protected lysine (RPL; 60 g/d) and methionine (RPM; 30 g/d) on nutrient digestibility, rumen fermentation, and microbial composition in 30 early-lactation Holstein dairy cows under both heat stress (HS) and non-heat stress (NHS) conditions. Cows were paired based on parity, milk yield, and body weight, and then assigned to one of two dietary treatments: the control group (CON), receiving the basal diet only, or the RPLM group, which received the basal diet supplemented with 60 g/d of RPL and 30 g/d of RPM (n = 15 per group). All animals underwent a transition from HS to NHS conditions during the experimental period, allowing for within-animal comparison across thermal environments. Results demonstrated that RPLM supplementation significantly improved the apparent digestibility of dry matter (DM), crude protein (CP), and neutral detergent fiber (NDF) (p < 0.05), with a significant treatment × environment interaction observed for DM digestibility (p < 0.01). Under HS conditions, RPLM reduced ruminal NH₃-N concentration (p < 0.05) and increased total volatile fatty acids (TVFA), acetate, and butyrate levels (p < 0.01), suggesting enhanced nitrogen utilization and energy metabolism. No significant effects were observed on ruminal pH or the acetate-to-propionate ratio. 16S rRNA sequencing revealed that RPLM supplementation increased the relative abundance of fiber-degrading and butyrate-producing taxa, including NK4A214_group, Christensenellaceae_R-7_group, norank_f__Muribaculaceae, and norank_f__F082. These microbial taxa exhibited strong positive correlations with DM and CP digestibility (p < 0.001). LEfSe analysis further confirmed their status as key microbial biomarkers in the RPLM-NHS group. Collectively, concurrent supplementation of RPL and RPM modulates the ruminal microbiota, alleviates HS-induced reductions in digestive efficiency, and enhances overall nutrient utilization in dairy cows. Full article

This study evaluated the effects of including 0, 150, 300, 450, and 600 g/kg of dry matter (DM) of spineless cactus (SC; Nopalea cochenillifera Salm-Dyck) plus urea and ammonium sulphate (UAS) (9:1), replacing Tifton-85 hay (Cynodon spp. cv. Tifton 85), on nutrient intake and digestibility, feeding behaviour, water intake, and rumen dynamics. Five rumen-fistulated and cannulated crossbred wethers were randomly assigned in a 5 × 5 Latin square design. A roughage:concentrate ratio of 70:30 was supplied. Organic matter (OM) and metabolisable energy (ME) intakes showed quadratic responses (p < 0.05), with maximum values of 1157 g/day and 14.50 MJ/day estimated at SC+UAS levels of 364 and 410 g/kg DM, respectively. Apparent digestibilities of DM, OM, and non-fibre carbohydrates, as well as water excretion in faeces and degradation rate of DM, increased with SC+UAS inclusion (p < 0.05). Indigestible neutral detergent fibre (NDF) intake, feeding and rumination times, voluntary water intake, NDF degradation and passage rates, as well as the indigestible NDF passage rate, decreased with SC+UAS inclusion (p < 0.05). In wethers’ diets with a roughage:concentrate ratio of 70:30, a roughage combination of SC+UAS and Tifton-85 hay in a 41:29 ratio is recommended to maximise ME intake. Full article

This study evaluated the potential of utilizing Sesbania cannabina, produced during saline–alkali soil improvement, as a high-quality feed resource for ruminants. Mixed silages were prepared by combining S. cannabina and whole corn at ratios of 1:1 and 1:3, with or without a compound Lactobacillus (LAB) inoculant, and were assessed for fermentation quality, nutrient composition, ruminal degradation, intestinal digestibility, and energy value. Results: The addition of Lactobacillus (LAB) inoculants increased lactic acid content, crude protein effective degradability (CPED), gross energy (GE), and dry matter apparent digestibility (DMAD), while decreasing ammonia nitrogen (NH₃-N), acetic acid (AA), propionic acid (PA), neutral detergent fiber (NDF), acid detergent fiber (ADF), rumen undegradable protein (RUP), intestinal crude protein degradability (ICPD), and intestinal digestible crude protein (IDCP). Increasing the proportion of whole corn increased dry matter (DM) and gross energy (GE), while reducing crude protein (CP), NDF, ADF, Ash, rumen degradable protein (RDP), RUP, IDCP, and the effective ruminal degradability of NDF (NDFED) and ADF (ADFED). Overall, a 1:1 mixing ratio maximized S. cannabina utilization without compromising feeding value, and LAB inoculation ensured successful ensiling while enhancing nutrient utilization. Full article

Defining appropriate dietary fiber levels is essential for enhancing the sustainability of feedlot lamb production. Optimal dietary fiber levels can enhance meat yield, improve nutrient retention and utilization, and reduce environmental impact. This study aimed to determine the optimal level of dietary fiber to enhance nutrient intake, digestibility, feeding behavior, and rumen fermentation in feedlot lambs. Five rumen-fistulated Santa Inês male lambs (40 kg, 7 months old) were used in a 5 × 5 Latin square design. Diets contained increasing levels of neutral detergent fiber (NDF): 200, 320, 440, 560, and 680 g/kg dry matter (DM), with each period lasting 21 days (total 105 days). Nutrient intake responded quadratically to NDF levels (p < 0.05). Apparent digestibility was significantly affected (p < 0.05), except for crude protein. Feeding (p = 0.001) and rumination times (p = 0.002) increased linearly, while idling time decreased (p < 0.001). Feeder visits declined (p = 0.002), and idling events followed a quadratic trend. Feeding and rumination efficiencies for DM decreased (p = 0.006 and p = 0.010), while NDF rumination efficiency increased (p = 0.014). The ruminal pH rose (p < 0.001), and propionate decreased (p = 0.019); acetate and butyrate showed quadratic responses. Based on intake, digestibility, and fermentation patterns, dietary NDF should be included at 400 g/kg DM to optimize nutrient utilization and rumen function in confined lambs. Full article

Based on an established appropriate substitution level for corn distillers dried grains with solubles (DDGSs) replacing energy-supplying components in the basal diet for pregnant sows, the substitution method was employed to determine the available energy values of corn DDGSs. In Exp. 1, forty pregnant sows (gestation day = 50 ± 5 d; body weight = 220 ± 24.9 kg; parity, 4 to 6) were randomly allocated into five treatments. The control group was fed a corn–soybean basal diet, while test diets contained 20%, 30%, 40%, 50% corn DDGSs replacing the energy-supplying portion of the basal diet. In Exp. 2, the available energy of five corn DDGS sources was determined using the substitution method at a 30% substitution level. Twelve pregnant sows (gestation day = 50 ± 5 d; body weight = 225.4 ± 29.2 kg; parity, 4 to 6) were arranged in a 6 × 3 Youden square design. Dietary treatments consisted of the corn–soybean basic diet and five test diets incorporating different corn DDGS types. Increasing the substitution level of corn DDGSs displayed both linear and quadratic effects (p < 0.05) on the apparent total tract digestibility (ATTD) of dry matter (DM), organic matter (OM), acid detergent fiber (ADF), ether extract (EE) and gross energy (GE) in diets. The ATTD of neutral detergent fiber (NDF), digestible energy (DE) and metabolizable energy (ME) was quadratically affected by different substitution levels (p < 0.05), with the highest value achieved at the 30% substitution level. As the substitution level of corn DDGSs increased, the ATTD of ADF in corn DDGSs decreased. In contrast, the ATTD of crude protein (CP) increased either linearly or quadratically (p < 0.05), and a significant quadratic effect was observed for the ATTD of EE in corn DDGSs (p < 0.05). Although the GE, DE, and ME of corn DDGSs were not significantly influenced by the substitution level, the 30% corn DDGSs resulted in the lowest coefficients of variation (CV). Therefore, a 30% substitution level of corn DDGSs is recommended for energy-supplying components in the basal diet of pregnant sows using the substitution method. The ranges of DE, ME and net energy (NE) of five corn DDGSs samples were 15.58–18.07, 12.17–16.42 and 8.76–15.88 MJ/kg DM, respectively. The absolute value of relative error (|RE|) between the predicted available energy values obtained from the prediction equations established in Exp. 2 and the determined values were below 5%, except for ME for corn DDGSs N3 (5.81%). Full article

This study aimed to evaluate the effects of yeast culture (YC) supplementation on growth performance, dietary nutrient digestibility, ruminal fermentation characteristics, methane (CH₄) synthesis potential, ruminal bacterial composition, antioxidant and immune capacities in beef cattle. Thirty-six finishing Simmental beef cattle were employed for this experiment. The experiment included three dietary treatments: the basal diet (CON), the basal diet supplemented with Diamon V XP (XP; 50 g/day per cattle), and the basal diet supplemented with Keliben (KLB; 50 g/day per cattle). Various metabolites, such as acetophenone (12.7%), ascorbic acid (10.3%), citric acid (7.25%), D-(+)-proline (6.42%), succinic acid (5.70%), betaine (5.65%) and DL-malic acid (2.62%) were abundant in XP; and ascorbic acid (14.0%), oleamide (9.23%), citric acid (6.03%), betaine (5.88%), succinic acid (4.42%), indole-3-acrylic acid (2.85%) and DL-malic acid (1.73%) were abundant in KLB. Supplementing YC to the cattle increased the apparent total-tract digestibility of DM, OM, NDF and ADF, and tended to increase average daily gain. The supplementation of YC to the cattle had no effect on the rumen fermentation pathway as reflected by the unaltered molar percentage of acetate or propionate. The supplementation of XP decreased the concentration of rumen dissolved CH₄, although no effect on the concentration of dissolved hydrogen was observed. The supplementation of KLB to the cattle increased Paraprevotella relative abundance, while the supplementation of XP decreased Euryarchaeota relative abundance in the rumen. Supplementing XP to the cattle increased serum GSH-Px, catalase and T-AOC concentrations, and was accompanied by decreased MAD concentration, indicating improved antioxidant capacity. Supplementing XP to the cattle increased the concentrations of serum IgA, IgG, IL-2, IL-10, IFN-γ and C4, compared with the CON group, and the KLB group had higher concentrations of serum IgA, IgG, IgM, IL-10, IFN-γ, C3 and C4 compared with the CON and XP groups, which revealed that both XP and KLB can improve the immune function, and that KLB showed a stronger effect. Overall, the supplementation of YC is beneficial to the nutrient digestibility, growth performance and health of beef cattle. Furthermore, XP was more effective than KLB in improving antioxidant capacity and reducing CH₄ production, while KLB was more effective in improving the immune capacity of beef cattle than XP. Full article

A study was conducted using 144 Hy-Line Brown laying hens (22 weeks old) to assess the impact of exogenous enzymes on energy utilisation and ileal nutrient digestibility in diets containing 300 g/kg wheat distillers’ dried grains with solubles (DDGS). A basal diet was prepared and divided into eight treatments: a control (C) and diets supplemented with 2000 units/kg xylanase (XYL), 500 units/kg phytase (PHY), and 4000 units/kg protease (PRO), individually and in combination. The diets were fed for nine days to six coops, each housing three birds. Feed intake, weight gain, and feed conversion ratio were recorded. The feed and excreta were analysed for gross energy, and the apparent metabolisable energy (AME) was calculated. On the final day, the birds were euthanised, and ileal digesta were collected, freeze-dried, and analysed for the digestibility coefficients of dry matter (DM), nitrogen, fat, and neutral detergent fibres (NDFs). XYL supplementation improved (p = 0.035) dietary AME but did not affect (p > 0.05) DM, nitrogen, fat, or NDF digestibility. No significant effects (p > 0.05) were observed for PHY or PRO, and no interactions (p > 0.05) were found between enzyme combinations. Substrates in experimental diets involving various enzyme combinations should be given careful consideration. Full article

The objective of this study to evaluate the effects of two levels of concentrate supplementation (1 g/kg or 2 g/kg of body weight, BW) on the intake, apparent digestibility and performance of Girolando steers on tropical pastures during the post-weaning phase in the dry to rainy season transition. We used 20 Girolando steers (half Holstein x half Zebu), with an average initial BW of 151.15 ± 50 kg and 12 months of age. The steers grazed on Urochloa brizantha cv. Marandu pasture. The animals were randomly assigned supplementation with 1 g/kg of BW (SC1) or supplementation with 2 g/kg of BW (SC2) of a concentrate supplement. The forage dry matter intake (%BW), neutral detergent fiber intake (NDF) and NDF digestibility were higher (p < 0.05) for steers supplemented with a level of 1 g/kg of BW. Supplement intake (kg/day), non-fibrous carbohydrate (NFC) intake and NFC digestibility were higher (p < 0.05) for steers consuming 2 g/kg BW of the concentrated supplement. The body weight at slaughter (297 kg) and average daily gain (0.57 kg/day) were not influenced by the level of supplementation. The use of 1 g/kg BW of a concentrated supplement is recommended for post-weaning steers on tropical pastures during the dry to rainy season transition. Full article

Olive oil production generates by-products, such as olive cake (OC), which can be used in animal feed, reducing the environmental impact. This study assessed the effects of OC in pig diets on intestinal morphometry and blood parameters. Twenty-four Bísaro pigs were randomly assigned to three treatments: OC0 (control), OC15 (15% dehydrated OC), and OC25 (25% dehydrated OC) for 93 days. The apparent total tract digestibility (ATTD) of dry matter (DM), organic matter (OM), crude protein (CP), crude fat (CF), and fiber (NDF) was evaluated through total feces collection. No significant differences in average daily gain (ADG) or feed conversion ratio (FCR) were found (p > 0.05). However, average daily feed intake (ADFI) increased from 2.84 kg (control) to 3.46 kg (OC15) and 3.64 kg (OC25). OC inclusion increased the ADFI of CF (90.8 g to 171.5 g and 169.2 g) and NDF (586.8 g to 896.6 g and 1115.4 g). The ATTD of all parameters decreased with 25% OC. The digestible intake of DM, OM, and CP was unaffected, but CF intake was higher in OC-fed groups (p = 0.005). Histomorphometric analysis revealed no significant differences in villi size. Lymphocyte counts were higher in OC25 (p < 0.05). This study suggests that up to 15% OC inclusion is feasible without compromising the pigs’ performance. Full article

The olive oil agro-industry generates large quantities of by-products, such as olive cake (OC), whose sustainable valorisation in animal feed can contribute to the principles of circular economy, waste reduction, and resource efficiency. This study evaluated the effects of incorporating OC into the diets of growing Bísaro pigs, focusing on productive parameters and the apparent total tract digestibility (ATTD). Two trials were carried out. In the first trial, 25 pigs were fed five diets containing 0, 5, 10, 15, and 20% exhausted OC (EOC) for 15 days. The results showed a linear decrease in ATTD with increasing EOC levels (p < 0.001), but the increased feed intake compensated for the reduced digestibility, and growth performance was maintained. The initial and final live weight (LW), average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) were not affected (p > 0.05). In the second trial, 40 pigs were fed five diets for 82 days: a control diet and four diets incorporating 10% crude OC, 10% two-phase OC, 10% EOC, and 10% EOC with 1% olive oil. No significant differences were observed in final weight, ADG, ADFI, FCR, or the digestibility of DM, OM, CP, CF, and NDF. The results suggest incorporating moderate levels of OC into Bísaro pig diets could be a viable strategy for valorising by-products, reducing agro-industrial waste and increasing sustainability in animal production. In addition, the inclusion of OC had no negative impact on animal performance, highlighting the potential of OC as a sustainable ingredient for animal feed, which aligns with the objectives of the circular economy and sustainable livestock farming practices. Full article

Corn, as a raw material supplying energy, plays an important role in animal husbandry. But in recent years, problems related to insufficient energy supply from corn have attracted increasing attention. Therefore, it is highly important to develop new energy-supplying materials to replace corn in animal diets. To study the feasibility of replacing corn with fermented corn straw in ruminants, 16 Yichang white goats were divided into two groups: those kept on a grain-based diet with dry corn straw (DS) and those fed a grain-based diet with fermented corn straw (FS). Corn in the FS group was replaced with fermented corn straw at a ratio of 1.3:1. By increasing the surface area (p = 0.035) and width (p = 0.024) of the rumen epithelial papillae of Yichang white goats, the absolute enzyme activity of carboxymethyl cellulase and the relative enzyme activity of microcrystalline cellulase in the rumen contents increased with fermented corn straw, and the rumen digestibility of cellulose and the whole intestinal apparent digestibility of CP, CF, NDF, ADF, cellulose and hemicellulose increased. The timely removal of excess calcium through feces and urine prevented liver and kidney damage, improved the heart index and liver index, and sustained goat health. Due to an increase in the abundance of beneficial bacteria such as f-Lachnospiraceae and c_Bacilli in the rumen fluid and colon contents, the abundance of potentially harmful bacteria such as s_Turicibacter decreased. Through the rumen pentose phosphate pathway, carbon metabolism, the AMPK signaling pathway, pathways of neurodegeneration, multiple diseases pathways, vitamin b6 metabolism in the colon, the biosynthesis of nucleotide sugars, and the cysteine and methionine metabolism pathways, rumen fermentation and metabolism are regulated in the goat body, promoting animal health. In this study, we systematically evaluated the effects of replacing corn with fermented corn straw on the carcass index, organ index, calcium and phosphorus contents in tissues, serum biochemical parameters, nutrient digestibility, rumen epithelium and intestinal development, rumen fermentation, and microbial enzyme activity of the rumen contents of Yichang white goats. By combining these approaches with microbial 16S amplicon analysis of rumen fluid and colon contents, along with nontargeted metabolome analysis, we demonstrated the feasibility of substituting corn with fermented corn straw in ruminant feed, providing a new approach for the substitution of energy-supplying feed materials. Full article

This experiment aimed to evaluate the impact of various feed additive-treated silage corn straw on the growth performance, blood parameters, nutrient apparent digestibility, and rumen fermentation in Simmental cattle. Eighteen healthy Simmental bulls (275.64 ± 15.27 kg) were randomly assigned to three groups, each consisting of six bulls: a control group (CON) receiving a basal diet, an experimental group, (OS) wherein 20% of the rice straw in the control group’s diet was substituted with silage corn straw treated with organic acid, and another experimental group (MS) wherein 20% of the rice straw was replaced with silage corn straw mixed with corn flour, lactic acid bacteria, and organic acid. All cattle were fed at 08:30 and 16:30, twice each day, with unrestricted access to water throughout the study. The results indicated that silage had no effect on the growth and serum biochemical indexes of beef cattle among all groups. However, other parameters, mainly rumen fermentation parameters, nutrient digestibility, and rumen microorganisms, were affected by the silage. The MS group significantly increased the concentration of microbial protein (MCP) in the rumen of cattle compared to the CON group. The OS and MS groups had a similar apparent digestibility of ether extract and acid detergent fiber (ADF), but a higher digestibility of dry matter (DM) (p = 0.001) and crude protein (CP) (p < 0.001) compared to the CON group. The rumen bacterial community of the MS group had a lower abundance of Proteobacteria than the CON group (p = 0.016). The abundance of Firmicutes in the MS group was not significantly different from the CON group, but there was an increasing trend compared with the OS group (p = 0.054). A Spearman correlation analysis showed that the apparent digestibility of NDF and CP was negatively correlated with Succinivibrionaceae UCG-002 (r = −0.552, p = 0.018; r = −0.668, p = 0.002), Succinimonas (r = −0.774, p < 0.001; r = −0.513, p = 0.029), and Ruminobacter (r = −0.583, p = 0.011; r = −0.618, p = 0.006). The apparent digestibility of DM exhibited a negative correlation with Succinivibrionaceae UCG-002 (r = −0.538, p = 0.021) and Succinimonas (r = −0.642, p = 0.004). Overall, corn straw silage with mixed additives has more feeding value, which can improve rumen fermentation and regulate the rumen bacterial community. Straw silage can change the rumen microbial community structure to improve the apparent digestibility of nutrients. Full article

This study aimed to investigate the effect of varying levels of dietary protein on digestion, metabolism, serum biochemical indexes, and rumen microflora in Lanzhou fat-tailed sheep. A total of twenty 8-month-old healthy rams with an initial average body weight (BW 25.16 ± 1.09 kg) were selected and randomly divided into four dietary treatments with different protein levels P: 9.47%, MP: 10.53%, HP: 11.56%, and EHP: 12.61%. The rams underwent a 23 day adaptation period, and the experiment was conducted for 7 d. The results showed that with increased dietary protein levels, the apparent digestibility of dry matter (DM), crude protein (CP), acid detergent fiber (ADF), and urine energy significantly increased (p < 0.05), increasing by 8.65%, 7.31%, 6.22%, and 0.1%, respectively. In contrast, the digestibility of neutral detergent fiber (NDF) first increased and then plateaued with the increase in protein levels, and the digestibility of NDF in the HP group was the highest (p < 0.05). The Shannon, Simpson, Chao1, and Ace indices of rumen microorganisms in the four groups did not change significantly (p > 0.05). Additionally, at the phylum level, the relative abundance of Bacteroidota, Firmicutes, and Verrucomicrobiota collectively accounted for over 91% of the total phylum composition. At the genus level, there was an increase in the relative abundance of uncultured_rumen_bacterium and Rikenellaceae_RC9_gut_group in the LP group, whereas the relative abundance of Prevotella decreased. In comparison to the other three groups, the HP group exhibited an increase in the relative abundance of Firmicutes. In summary, dietary protein level had no significant effects on the rumen microflora structure and blood biochemical indexes. However, diets with a high protein level can improve the apparent digestibility of nutrients and energy use efficiency of Lanzhou fat-tailed sheep. Full article