Search Results (706)

This study evaluated the effects of Nypa fruticans fruit pellet supplementation combined with different CP levels on rumen fermentation characteristics and CH₄ production using an in vitro gas production technique. A 3 × 4 factorial arrangement was used, consisting of three CP levels (12, 14, and 16%) and four levels of Nypa fruticans fruit pellet supplementation (0, 0.5, 1.0, and 1.5% of substrate dry matter), with incubation run included as a random effect in the statistical model. Rumen fluid from Thai native beef cattle was incubated under anaerobic conditions. Gas production kinetics, ruminal pH, ammonia–nitrogen (NH₃–N), protozoal populations, digestibility, volatile fatty acids (VFA), and CH₄ production were determined. Significant interactions between CP level and Nypa fruticans fruit pellet supplementation were observed for gas production kinetics. Ruminal pH was influenced by CP level at 24 h, while NH₃–N increased with higher CP levels but decreased with increasing supplementation. Protozoal populations were reduced by Nypa fruticans fruit pellets. Methane production was affected by CP level, Nypa fruticans fruit pellet supplementation, and their interaction. A clearer reduction was observed at 24 h, particularly at higher supplementation levels. At 24 h of incubation, total VFA, propionate, and butyrate concentrations increased with supplementation, whereas no clear effects were observed at 12 h. In vitro dry matter digestibility was affected at 24 h (p < 0.05), but no effect was observed at 48 h, while organic matter digestibility remained unchanged. In conclusion, Nypa fruticans fruit pellets, in combination with CP level, modified rumen fermentation patterns and were associated with lower CH₄ production under in vitro conditions, without negatively affecting digestibility. These findings suggest potential for further in vivo evaluation. Full article

This study aims to evaluate the blanching process of wasted Undaria pinnatifida as a ruminant feed source by assessing chemical compositions, in vitro nutrient digestibility, rumen fermentation characteristics, greenhouse gas emissions, and rumen microbes. The blanching process was conducted at different temperatures (15 vs. 80 vs. 90 °C) and times (2 vs. 4 min) to assess the chemical and mineral contents. Supplementation levels of U. pinnatifida (0 vs. 0.5 vs. 1 vs. 2%) were observed with the blanching process (non-blanching (NBL) vs. blanching (LOS)). Increasing blanching temperature and time decreased (p < 0.05) dry matter, crude ash, and the mineral contents, including sodium, phosphorus, and arsenic. Moreover, LOS treatment increased (p < 0.01) in vitro dry matter and neutral detergent fiber digestibility, ruminal pH, and the acetate-to-propionate ratio, but reduced (p < 0.01) CH₄ (mL/g NDFD). Additionally, 2% of LOS treatment reduced the abundance of protozoa, fungi, fibrolytic microbes, methanogenic archaea, Methanobrevibacter ruminantium, Methanosarcina barkeri, and Methanosphaera stadtmanae (p < 0.01). Therefore, blanching at 80 °C for 2 min improved the nutritional profile by reducing antinutritional minerals. Subsequent in vitro fermentation suggested that supplementing the diet with 0.5–1% of LOS improved digestibility and altered fermentation, potentially reducing methane yield (per NDFD). Full article

This meta-analysis and meta-regression evaluated how malic acid supplementation modulates rumen fermentation and its consequences for growth performance, nutrient digestibility, and carcass traits in lambs. Effect sizes (ES) were estimated using a random-effects model. Dietary composition was explored by meta-regression as a key source of heterogeneity, and subgroup analyses were used to compare free malic acid (FMA) and malate. Ruminal pH was not affected by malic acid supplementation. In contrast, total volatile fatty acid concentration increased with malic acid supplementation, particularly in studies using FMA. No effects were detected for propionate concentration, whereas acetate concentration increased (ES = 0.502; p = 0.036). A tendency toward a reduced ruminal acetate proportion was observed (ES = −0.683; p = 0.072). Malic acid supplementation tended (p = 0.057) to increase body weight gain (BWG; ES = 0.325) and final body weight (FBW; ES = 0.234). Malic acid supplementation did not affect carcass traits or overall nutrient digestibility. Meta-regression consistently identified fiber intake-related variables as major moderators of the effects of malic acid. Overall, the effects of malic acid supplementation on lamb performance appear to be primarily driven by its modulation of rumen fermentation and strongly conditioned by dietary context. Full article

The intensive lamb rearing and finishing systems are usually based on nutritionally balanced concentrate-based rations. However, the inclusion of feed additives is often necessary to avoid possible disturbances of digestibility. Artificial saliva plays an important role in ruminal buffering, improving the digestibility of the feed under conditions where natural saliva production may be insufficient. The study aimed to evaluate the effects of dietary artificial saliva (AS) on the total mixed ration (TMR) on lambs’ growth performance, carcass characteristics and the efficacy of ruminal fermentation. Forty-five male Naemi lambs (mean body weight of 23 ± 1.8 kg) were randomly assigned to five experimental groups (n = 9 per group) and kept in complete confinement with water and adlibitum feeding. During the 84-day feeding period, animals received isonitrogenous and isoenergetic TMRs that vary in AS inclusion by level: T0 (0% AS), T2 (1.5% AS), T3 (3.0% AS), T4 (4.5% AS), and T5 (6% AS). No significant differences (p > 0.05) were observed in the overall performance parameters. However, lambs fed the control diet (0% AS) had a higher body weight (BW), average daily gain (ADG), and feed intake (FI) than those receiving AS supplementation (p < 0.01). Ruminal pH measured 3 h after feeding and at slaughter remained comparatively stable in lambs fed 3% and 4.5% AS treatments, whereas it declined to 5.21 in the control group. Dietary inclusion of AS at 4.5% significantly increased (p < 0.05 < 0.05) the molar proportions of butyric acid, iso-valeric acid, and valeric acid in ruminal fluid while other levels of artificial saliva were associated with reduced concentrations of volatile fatty acids (VFAs). In conclusion, AS effectively functioned as a buffering agent, enhancing dietary safety without adverse health effects. Full article

Water-soluble carbohydrate (WSC) is the key to producing quality forage silage and an important energy source for ruminants. The aim of this study was to investigate the effect of different silages used as roughage sources [whole-plant sugarcane silage (WSS) vs. elephant grass silage (EGS)] with varying levels of WSC on silage quality, buffalo growth performance, apparent digestibility, rumen fermentation, and microbial communities. Sixteen healthy male crossbred buffaloes were randomly divided into two treatment groups, with eight buffaloes/treatment. One group was fed whole-plant sugarcane silage, and the other group was fed elephant grass silage. Compared with EGS, WSS had higher WSC, lactic acid, and ethanol, but lower pH, ammonia nitrogen, propionic acid, and butyric acid (BA) contents (p < 0.05). Potential probiotics (e.g., Lactiplantibacillus and Hanseniaspora) were more abundant in WSS than in EGS (p < 0.05). Moreover, the feed conversion rate was higher in HWS (p < 0.05). However, rumen fermentation parameters were unaffected by diet (p > 0.05). Moreover, feeding WSS had lower dry matter digestibility (DMD), organic matter digestibility (OMD), and lower acid detergent fiber digestibility (ADFD) (p < 0.05). After WSS feeding, ruminal Treponema_2 was strongly associated with DMD, OMD, and ADFD (p < 0.05), and also showed positive correlations with BA and PA contents in WSS (p < 0.05). Additionally, rumen Ruminiclostridium_5 and Pseudozyma was associated with DMD and ADFD after being fed EGS (p > 0.05), respectively, but the Pseudozyma was associated with BA (p < 0.05) and Clostridium_sensu_stricto_11 (p > 0.05) in EGS. Our findings indicated that WSS exhibited superior fermentation quality and harbored potential beneficial microbes, whereas EGS showed higher apparent nutrient digestibility in buffalo but also contained undesirable bacteria (e.g., Clostridium_sensu_stricto_11). Future research should investigate the long-term effects of WSS feeding on buffalo health, immunity, and production performance, as well as its impact on rumen microbiota stability, to fully assess its potential as a safe and sustainable roughage source. Full article

This study evaluated the effects of forage-free diets with reduced starch levels on the productive performance, metabolism, ruminal fermentation, nutrient digestibility, and meat quality of feedlot beef cattle. Two experiments were conducted. In Experiment 1, forty uncastrated Nellore steers were distributed into 20 pens in a completely randomized design, receiving diets with increasing inclusion levels of ground corn in the total diet: C400 (400 g kg⁻¹), C200 (200 g kg⁻¹), C100 (100 g kg⁻¹), and C50 (50 g kg⁻¹), formulated without forage and based on fibrous co-products. Increasing ground corn inclusion promoted linear improvements in final body weight and average daily gain, while dry matter intake and feed efficiency showed quadratic responses. Meat quality parameters were not affected by dietary treatments. In Experiment 2, eight crossbred steers were assigned to a double 4 × 4 Latin square design and fed the same experimental diets. Higher corn inclusion increased starch and fat intake, whereas dry matter, organic matter, and protein intake showed quadratic responses. Apparent total-tract digestibility of dry matter, organic matter, and starch also followed a quadratic pattern. Ruminal fermentation parameters were affected by dietary treatments, with greater ammoniacal nitrogen concentrations at higher corn levels and quadratic responses for propionate, butyrate, and methane production. Nitrogen metabolism indicated increased urinary nitrogen and uric acid excretion with increasing dietary corn inclusion. These results demonstrate that forage-free diets based on citrus pulp and soybean hulls with different levels of ground corn can be effectively used in finishing beef cattle, improving performance without impairing meat quality while modulating ruminal fermentation and nutrient utilization. Full article

Nigella sativa meal (NSM) is a by-product of the oil extraction process with potential use as a functional feed ingredient in ruminant nutrition due to its rich bioactive compounds and nutrient content. Therefore, this replicated (n = 6) completely randomized design (CRD) study aimed to firstly characterize NSM for its the bioactive compounds by chromatography–mass spectrometry (GC–MS) and liquid chromatography–MS (LC–MS). The effects of its dietary inclusion at 0%, 5%, 7.5%, and 10% NSM on in vitro rumen fermentation, gas production, CH₄ production, and rumen degradability were analyzed. Rumen fluid was collected orally from five sheep (body weight 20 ± 2 kg/head) and incubated with basal diets supplemented with pre-determined levels of NSM. The identified bioactive compounds identified included palmitic acid, oleic acid, linoleic acid, phenolic, flavonoid, thymoquinone, and saponin. The results showed that the dietary NSM supplementation in the diet significantly increased (p < 0.05) gas production at 18 and 48 h, NH₃–N concentration, IVDMD (In vitro dry matter degradability), and IVOMD (In vitro organic matter degradability). However, there was no significant effect (p > 0.05) on gas production at 12 and 24 h, and CH₄ production, pH, acetate, propionate, iso-butyrate, butyrate, iso-valerate, valerate, the acetate-to-propionate ratio (A:P), or total VFA concentration. Rumen fermentation was optimally modulated up to 10% without adverse effects on digestibility or CH₄ production. In this context, NSM acted as a functional feed ingredient in vitro. Therefore, in vivo analyses are required to confirm the efficacy under practical feeding conditions. Full article

The rumen simulation technique (RUSITEC^®) is a known model for research in rumen microbiology and fermentation. However, our research group observed inconsistencies in gas production across trials. This study investigated the effects of different gas outlet locations on digestibility, ruminal fermentation, gas production, and microbial protein synthesis. Fifteen fermenters tested three different gas outlet locations within the RUSITEC^® equipment: (1) gas outlet directly on the effluent vessel for output liquid (EV); (2) gas outlet directly on fermenter cap (F); and (3) gas outlet on both effluent vessel and fermenter cap (EVF). Data were analyzed using a completely randomized design in SAS (v. 9.4) with the MIXED procedure, and significance was set at p < 0.10. Results showed that altering the gas outlet location did not affect nutrient digestibility (p > 0.10), microbial protein synthesis (p > 0.10), and volatile fatty acid (VFA) production when expressed on a molar basis (p > 0.10). However, total gas production (p = 0.108) was higher in the EVF group and ammonia nitrogen produced in the fermenter was higher in group F (p = 0.081). Furthermore, methane (CH₄) production was underestimated when the gas outlet location was in just one of the locations when compared to the EVF group (p = 0.006). VFA proportion was also affected, with lower acetate (p = 0.005) and higher butyrate (p = 0.014) for group EV. These results indicate that the location of the gas outlet is an important methodological factor affecting fermentation measurements in the RUSITEC system, with outlets positioned in both the effluent and fermenter vessels enhancing gas recovery. Full article

In ruminant nutrition, the lignocellulosic complex is a primary constraint limiting the utilization of dietary fiber. The objective of this study was to evaluate the effects of inoculating lignin-degrading bacteria (LDB) isolated from the ruminant rectum on in vitro rumen fermentation characteristics. Rectal fecal samples were collected from healthy beef cattle, dairy cattle, buffaloes, and goats (n = 4 per species) using the grab sampling technique. Twenty-eight bacterial colonies were isolated through enrichment and screening on media containing sodium lignosulfonate. Lignin degradation efficiency was assessed spectrophotometrically, while laccase activity was determined using a 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) oxidation assay. Seven isolates exhibiting ligninolytic activity (1.4–5.6% degradation efficiency) were selected to evaluate their effects on in vitro rumen fermentation using a completely randomized design with four replicates. LDB treatments were standardized to a concentration of 2.4 × 10⁵ colony-forming units/mL of rumen fluid medium, while the control received an equal volume of a 0.85% sterile NaCl solution. A rice straw-based total mixed ration served as the substrate, with rumen fluid collected from beef cattle. All treatments were incubated for 48 h. Notably, isolate BC3 consistently enhanced in vitro dry matter digestibility (23.1%), total gas production (18.6%), and total volatile fatty acid concentrations (13.2%) relative to the control and other LDB isolates (p < 0.01). All seven LDB isolates were identified as Gram-negative, rod-shaped, facultative anaerobic bacteria that exhibit catalase activity and tolerate moderately acidic conditions. Phylogenetic tree analysis based on 16S rRNA gene sequencing identified isolate BC3 as being closely related to Escherichia coli strains. These findings demonstrate that the ruminant hindgut is a promising source of LDB with the functional potential to enhance feed digestibility and fermentation end-products in the rumen. Future research should prioritize in vivo trials to evaluate the safety and efficacy of LDB as a direct-fed microbial, specifically focusing on its impact on animal performance and health. Full article

Saliva is an important biological matrix that allows the investigation of various welfare parameters; in ruminants, it is abundant and can be easily collected without requiring professional veterinary intervention. The aim of the investigation was to provide additional information on both digestive and antioxidant enzymes of sheep farmed in good welfare conditions, assessed with the Animal welfare indicators (AWIN) protocol. Small surgical forceps holding a Salivette^® device (Sarstedt, Nümbrecht, Germany) were gently inserted into the sheep’s mouths without any force. The sheep chewed the swabs independently for a few seconds, allowing saliva collection. Seventeen enzymes from the saliva of 15 sheep were analyzed: antioxidant enzymes (catalase, glutathione S transferase), proteolytic enzymes (trypsin, chymotrypsin, N-aminopeptidases, carboxypeptidase A and B), carbohydrases (glucose oxidase, amylase, cellulase, lignin peroxidase, chitinase and α-glycosidase), and esterases (alkaline and acidic phosphatases, lipase and esterase). Esterase activity showed the highest value (12.95 ± 1.25 U/mg of proteins), whereas lignin peroxidase activity showed the lowest (2.23 ± 0.37 µU/mg of proteins). The activity of all enzymes was observed except for glutathione S transferase and α-glycosidase. Among the enzymes, lipase activity has already been identified as a biomarker of stress in sheep saliva. This investigation may represent a basis for further investigations into the diet and adaptive responses of sheep to different environmental conditions. Furthermore, samples collected using the Salivette^® device can be easily obtained without requiring specialized staff and without causing any stress to the animals. Further investigations into the origin of individual enzymes using a proteomic approach are desirable. Full article

This study evaluated the effects of increasing proportions of sudangrass sorghum forage in ruminant diets, with or without polyethylene glycol (PEG), on rumen fermentation, gas and methane production, nutrient digestibility, and protein fermentation metabolites. Three experimental diets containing 20%, 40%, or 60% sorghum forage (S20, S40, and S60) were incubated in vitro with cattle rumen fluid. Incubations were performed with or without PEG used as a tannin-binding agent. After 24 h of incubation, gas and methane production, in vitro dry matter digestibility (DMD), neutral detergent fiber digestibility (NDFD), ammonia nitrogen concentration (N-NH₃), and volatile fatty acid (VFA) production and profiles were measured. Increasing sorghum inclusion resulted in a significant reduction in DMD (p = 0.0012). In contrast, NDFD increased (p = 0.0005), likely due to differences in lignin content among diets. Methane production was unaffected by the proportion of sorghum, despite the increasing tannin content. PEG supplementation significantly increased N-NH₃ concentration (p = 0.042) and isobutyric molar proportion (p < 0.0001), indicating enhanced rumen protein degradation following tannin neutralization. The total VFA concentration was not influenced by either sorghum level or PEG treatment. However, higher sorghum inclusion was associated with shifts in the VFA profiles toward higher acetate (p = 0.0023) and lower butyrate proportions (p = 0.0114). Overall, the results suggest that moderate levels of condensed tannins (CTs) in sorghum forage may alter rumen fermentation patterns without markedly reducing methane production. PEG supplementation further confirmed the biological activity of tannins, especially regarding protein metabolism. Therefore, sudangrass sorghum may be considered a viable forage option for ruminant diets, provided its inclusion level and tannin effects are carefully managed. Full article

Current research is still striving to maximize the expansion of protein feed sources in order to reduce the production costs of the livestock industry. In this context, the current study aimed to evaluate the impacts of replacing soybean meal protein in diets with mulberry silage (at 50 and 100% substitution levels) on the growth, health status, and carcass characteristics of growing goat kids. Forty-five Xiangdong black goat kids weighing 18.2 ± 1.6 kg (approximately 6 months old) were divided into three experimental groups and fed one of the following diets: a control diet consisting of a 50:50 concentrate-to-roughage ratio on a dry matter basis (control), a diet replacing 50% of soybean meal protein with mulberry silage (MS-50), or a diet replacing 100% of soybean meal protein with mulberry silage (MS-100). The results show that replacing soybean meal protein with mulberry silage significantly increased (p < 0.05) the intakes of dry matter (DMI), crude protein (CPI), neutral detergent fiber (NDFI), and organic matter (OMI). However, no significant (p > 0.05) differences were observed in the digestibility of dry matter (DM), crude protein (CP), ether extract (EE), or neutral detergent fiber (NDF) among the groups, whereas the digestibility of OM and acid detergent fiber (ADF) was significantly reduced (p < 0.05) in the MS-100 group. Additionally, the MS-100 group exhibited significantly higher (p < 0.05) plasma total protein, albumin, and calcium levels. Total antioxidant capacity (TAC) was significantly enhanced in both the MS-50 and MS-100 groups compared to the control, although the MS-100 showed a significant increase (p < 0.05) in malondialdehyde (MDA) levels related to the other groups. In terms of growth performance, the MS-100 group improved (p < 0.05) final body weight, average daily gain, and carcass weights. Meanwhile, the MS-50 group recorded the highest contents (p < 0.05) of the following amino acids: aspartic acid, threonine, serine, glutamic acid, alanine, lysine, and proline. Overall, the results of the present study indicate that replacing soybean meal protein with mulberry silage generally produced comparable impacts, with additional positive effects on growth performance, meat quality, and health status of goats. Full article

Global demand for animal protein necessitates sustainable alternatives to soybean meal (SBM). This systematic review evaluated 177 peer-reviewed articles (2002–2023) across 12 categories to analyse the nutritional value of alternative protein sources for ruminant diets and to assess the associated environmental trade-offs. This was achieved through a targeted review, synthesising data from Life Cycle Assessments (LCAs) to create a multi-criteria matrix for ranking sustainability profiles. Results indicate that microalgae, insects, and single-cell proteins exhibit crude protein levels comparable to SBM. Moreover, insects, seaweeds, and animal by-products (ABPs) often present superior essential amino acid profiles and high intestinal digestibility. From an environmental perspective, insects, seaweeds and microalgae offer excellent land-use efficiency and significant enteric methane mitigation (17–74.6%), though current economic viability is hindered by high processing costs and emerging supply chains. Conversely, ABPs and agro-industrial by-products effectively embody circular economy principles, enhancing local system resilience. Ultimately, replacing SBM requires a multi-objective approach through a functional hybridisation model, carefully balancing metabolic efficiency with environmental sustainability. While microalgae, insects, and seaweeds demonstrate promising nutritional and mitigation potential, addressing economic barriers and ensuring biosecurity seems essential. Future LCA frameworks should prioritise bioavailable nutrient metrics to optimise the environmental impact of ruminant production. Full article

Milk is a highly nutritious food and a cornerstone of the human diet, supplying not only essential macronutrients but also a wide range of bioactive compounds with important functional and health-promoting properties. This study presents the first comparative analysis of ruminant (cow, goat, sheep) and equine (mare, jenny) milk samples collected in Serbia, with emphasis on their physicochemical properties, protein profile, redox characteristics, and nutritional potential. Ruminant milk had significantly higher protein concentrations, with cow and sheep milk containing the highest levels of protein. Two equine milks demonstrated a distinctive whey-to-casein protein ratio to ruminants, and a higher content of active sulfhydryl groups, correlating with improved digestibility and functional properties. Antioxidant potential was determined using spectrophotometric and electrochemical methods, confirming superior redox potential in mare’s milk, followed by jenny’s and sheep’s milk. Nutritional properties of milk separated by Principal Component Analysis highlighted species-specific profiles of equine milks as a promising alternative for individuals with an allergy to cow’s milk protein, offering enhanced antioxidant protection, bioactive compounds, and digestibility. These results support the potential of equine milk as a functional food with added value in human nutrition. Full article

The potential of Rhodotorula yeast culture (RYC) in animal production remains underexplored. This study investigated the effects of RYC supplementation on nutrient apparent digestibility, rumen tissue morphology, fermentation parameters, and fungal microbiota in sheep. Twenty-four three-month-old male Dorper × Han crossbred sheep (weight 36 ± 4 kg) were selected and randomly divided into four groups, with six sheep in each group: the control group (CON) was fed a basal diet, and the three treatment groups were supplemented with 10, 20, or 40 g/d of RYC (RYC10, RYC20, RYC40), respectively. The results showed that RYC supplementation significantly increased (p < 0.05) the apparent digestibility of dry matter, crude protein, neutral detergent fiber, and acid detergent fiber, and the apparent digestibility of CP and ADF was significantly higher in the RYC20 than in the other groups (p < 0.05). Rumen papillae length and muscular layer thickness were significantly greater (p < 0.05) in RYC-treated groups compared to the CON group, and the RYC20 group exhibited significantly greater rumen papilla length and muscularis propria thickness than the other experimental groups (p < 0.05). Furthermore, ruminal pH and bacterial crude protein content were significantly elevated (p < 0.05), while ammonia nitrogen concentration was significantly reduced (p < 0.05). The RYC40 group exhibited significantly higher rumen pH and BCP concentrations, and significantly lower NH3-N concentration, compared to the other experimental groups (p < 0.05). The concentrations of acetate, propionate, butyrate, and total volatile fatty acids were also significantly higher (p < 0.05) in RYC groups. For RYC20, rumen acetic acid, propionic acid, butyric acid, isobutyric acid, total volatile fatty acid content and the acetate-to-propionate ratio were significantly higher than those of the other experimental groups (p < 0.05). Analysis of fungal community revealed that RYC increased the relative abundance of fibrolytic fungi (e.g., Neocallimastix, Caecomyce, Piromyces). Supplementation of RYC at 20 g/d optimizes apparent nutrient digestibility and rumen tissue development in ruminants, while maintaining favorable rumen fermentation characteristics and selectively enhancing the growth of core fibrolytic fungi; this dosage achieves the optimal balance of biological performance and economic feasibility, and is thus recommended as the optimal practical supplementation dosage for ruminant production. Full article