Search Results (907)

Ensuring high-quality forage under Mediterranean conditions requires careful evaluation of genetic resources. Two perennial forage species, cocksfoot (Dactylis glomerata L.) and tall fescue (Festuca arundinacea Schreb.), were evaluated to determine the stability and broad-sense heritability of major forage quality traits across Greek environments. The objective was to identify stable, heritable traits contributing to consistent forage quality under climatic variability. Measured traits included crude protein (CP%), crude fiber (CF%), ash, acid detergent fiber (ADF), neutral detergent fiber (NDF), cellulose, hemicellulose, acid detergent lignin (ADL), digestible dry matter (DDM%), dry matter intake (DMI%), and relative feed value (RFV). Significant genotype × environment (G × E) interactions were observed for most traits, highlighting the importance of multi-environment testing, except for RFV in cocksfoot, which was non-significant. Principal Component Analysis (PCA) helped clarify how these traits covary across environments. The traits Crude Protein, Ash Content, and ADL (on PC1) are largely independent of the traits Cellulose and Hemicellulose (on PC2) in the case of cocksfoot. The pattern of loadings in the case of Tall fescue revealed that hemicellulose represents a completely separate dimension of variation, which is uncorrelated to the rest of the traits that form a unified, highly correlated group. In both cases, the first two PCs explained over 82% of the total variance, separating genotypes and environments. By integrating stability (SI) and heritability (H²) results, Cock2D and T2fes were identified as the most stable and high-performing genotypes across environments. These findings could support breeding strategies for developing resilient forage cultivars with consistent quality and adaptability to Mediterranean environments, thereby enhancing sustainable livestock production. Full article

While livestock production is a significant source of greenhouse gas emissions, it remains vital for fulfilling the growing global demand for animal protein. Including by-products in ruminant diets can enhance food circularity and reduce competition for human food, while also increasing the likelihood of reducing methane (CH₄) emissions. This study aimed to evaluate the impact of fully replacing corn grain and urea in the control diet with local by-products, specifically corn distillers’ grains combined with either barley brewed grains or with wheat middlings, on enteric CH₄ emissions and performance of sheep. Diets were balanced to be isoproteic and isoenergetic with 2.6 Mcal ME/kg of dry matter (DM) and 160 g crude protein/kg DM, respectively. Corn silage is the only source of forage in the diet, and the forage-to-concentrate ratio was maintained to 60:40 on a DM basis. Twelve Highlander female sheep of 35.9 ± 3.12 kg initial body weight (BW, mean ± standard deviation), were used in a Completely Randomized Block design, with four sheep per treatment and two measurement periods under the same treatment. Experiment lasted 60 d, 30 d acclimatization and 30 d measurements. Dry matter intake (DMI) was restricted to 2.5% of BW. Enteric CH₄ emissions of individual sheep were quantified in respiration chambers over a 48 h period. Dietary treatments did not have a significant effect either on DMI or BW gain. The diet containing barley brewed grains significantly reduced total daily CH₄ production by 22.3%, CH₄ emissions per kg of DMI by 34% and energy loss as CH₄ by 38% compared to the control diet. In conclusion, the agro-industrial by-products combinations evaluated in this study effectively replaced corn grain and urea without compromising feed intake or animal performance. Additionally, the diet containing barley brewed grains significantly reduced CH₄ yield, and energy loss compared to the control diet. Full article

Variation in individual animal feed intake is influenced by factors such as bunk management, digestive physiology, social hierarchy, and health status. While previous research has primarily examined feeding behavior in cattle offered high-concentrate diets, limited information exists regarding these relationships in high-forage systems. Residual Feed Intake (RFI), defined as the difference between an animal’s actual and expected feed intake based on metabolic mid-test body weight and average daily gain, serves as a key measure of feed efficiency. Animals with negative RFI values are classified as more efficient, whereas those with positive values are less efficient. This study investigated associations between feeding behavior and feed efficiency in yearling purebred Angus bulls (n = 232) and heifers (n = 58) consuming forage-based diets using a Vytelle feeding system. Upon arrival, bulls averaged 350.3 ± 3.6 kg and heifers averaged 287.5 ± 5.0 kg, with a subsequent 14-day acclimation followed by a 49-day ad libitum feeding period. In bulls, RFI was positively correlated with bunk visits (r = 0.34, p < 0.0001) and negatively correlated with duration (r = −0.16, p = 0.0124). In heifers, daily visits were negatively correlated with intake (r = −0.88, p < 0.0001), and RFI was negatively associated with RADG (r = −0.53, p < 0.0001). Full article

Anaerobic fungi (phylum Neocallimastigomycota) play a crucial role in degrading forages and fibrous foods in the gastrointestinal tract of mammalian herbivores, particularly ruminants. Currently, they are classified into twenty-two genera; however, recent research suggests the occurrence of several novel taxa that require further characterization. Anaerobic rumen fungi play a pivotal role in lignocellulose degradation due to their unique enzymatic capabilities. This review explores the enzymatic systems of rumen anaerobic fungi, highlighting their ability to produce a diverse array of carbohydrate-active enzymes (CAZymes), such as cellulases, hemicellulases, and pectinases. These enzymes facilitate the breakdown of complex plant polymers, making anaerobic fungi essential contributors to fiber degradation in the rumen ecosystem and valuable resources for biotechnological applications. This review summarizes the structural and functional diversity of fungal CAZymes, and the mechanical disruption of plant cell walls by fungal rhizoidal networks is discussed, showcasing the ability of fungi to enhance substrate accessibility and facilitate microbial colonization. Recent studies using genomic, transcriptomic, and biochemical approaches have uncovered several novel CAZymes in anaerobic fungi, including multifunctional xylanases, β-glucosidases, and esterases. These findings highlight the continued expansion of fungal enzyme repertoires and their potential for biotechnology and feed applications. Continued research in this field will enhance our understanding of microbial ecology and enzyme function, paving the way for applications that address global challenges in energy, food security, and environmental sustainability. Full article

(1) Background: In arid regions, limited forage availability increases feeding costs for small ruminants. Sunflower hulls (SFH), a low-cost agro-industrial by-product, may serve as an alternative fiber source, yet their effects on pregnant Naemi ewes remain unclear. This study aimed to evaluate how graded levels of SFH affect intake, digestibility, rumen fermentation, and metabolic responses during gestation and early lactation. (2) Methods: Eighty-four ewes were assigned to diets containing 0%, 12%, 20%, or 28% SFH in a total mixed ration and monitored across early gestation, late gestation, and lactation. (3) Results: Increasing SFH significantly increased dry matter intake, with the highest intake in the 28% SFH group (p < 0.05). Body weight remained unaffected, whereas body condition score varied by physiological stage. Digestibility of major nutrients was unchanged; however, acid detergent lignin digestibility increased at 28% SFH (p < 0.05). Higher SFH levels (20–28%) reduced total volatile fatty acids by approximately 12–18% and lowered acetate and propionate concentrations, especially in late gestation. Blood metabolites differed among treatments but remained within physiological reference ranges, confirming metabolic safety. (4) Conclusions: SFH can be safely included at up to 28% of diet dry matter; however, 12–20% SFH appears most practical, supporting adequate fiber intake without compromising rumen fermentation efficiency. This provides a cost-effective strategy for ewe feeding under forage-limited arid conditions. Full article

Thirty-six Dorper × Katahdin intact male lambs [44.0 ± 0.27 kg initial body weight (BW)] were used in a randomized complete block design to evaluate the effects of supplementing different organic chromium (OrCr) sources on growth performance, dietary energetics, carcass traits, meat quality, and economic return. Treatments (n = 9 lambs/treatment) were (1) Control (no Cr), (2) chromium-enriched yeast (Cr-Yeast), (3) chromium–methionine (Cr-Met), and (4) chromium–propionate (Cr-Pr). All Cr sources were provided at 1.2 mg elemental Cr/lamb/d for 45 d. Lambs received a high-energy finishing diet (78:22 concentrate/forage; steam-rolled corn-based). Dry matter intake was not affected (p = 0.583; 1.27 ± 0.034 kg/d). Compared with Control, Cr-Pr increased final BW (+5%; p = 0.025) and average daily gain (+66%; p = 0.034), and improved feed efficiency (+59%; p = 0.045) and observed-to-expected net energy ratio (+22%; p = 0.042); Cr-Met and Cr-Yeast showed intermediate responses. No differences were observed (p > 0.05) in longissimus lumborum muscle area, cold carcass weight, dressing percentage, cooling loss, or zoometric traits. Rib and rump fat thickness decreased with Cr-Met (−15 and −12%; p = 0.024 and p = 0.048) and with Cr-Pr (−19 and −13%; p = 0.024 and p = 0.048), and all OrCr sources reduced omental (−6 to −25%; p = 0.034), mesenteric (≈−7%; p = 0.042), visceral (−12 to −16%; p = 0.034), and perirenal fat (−25 to −39%; p = 0.028). Empty body weight and hot carcass weight increased with Cr-Pr (p = 0.029 and p = 0.031, respectively). Cr-Yeast and Cr-Pr increased muscle proportion (+5 to +7%; p = 0.003) and reduced carcass fat (−20 to −27%; p = 0.018), improving the muscle/fat ratio (+42 to +50%; p = 0.045). Cr-Pr improved water-holding capacity (+27%; p = 0.014) without affecting pH_24h, purge loss, cooking loss, or Warner–Bratzler shear force (p > 0.05). Cr-Pr reduced cost per kg of gain (−31%; p < 0.001) and increased income (+188% live; +105% carcass; p < 0.001), whereas Cr-Met and Cr-Yeast provided moderate benefits. In conclusion, OrCr supplementation improved dietary energy utilization, growth, carcass traits, and meat quality, enhancing profitability in lambs finished at heavier weights, with Cr-Pr producing the greatest responses. Full article

This systematic review evaluated 28 peer-reviewed studies on the use of hydroponic forage in ruminant diets, following PRISMA 2020 guidelines. Hydroponic barley sprouts contain on average 14.8 ± 2.1% CP, 3.6 ± 0.4% EE, 12.9 ± 1.7% NDF, 7.8 ± 1.2% ADF, and 10.5 ± 2.8% DM (mean ± SD; n = 21 studies), and mineral content, though limited by high moisture and low dry matter yield. Among the included studies, 61% focused on barley, confirming its suitability for hydroponic cultivation. In dairy cattle, hydroponic forage improved milk fat content and oleic acid (C18:1), linoleic acid (C18:2), and α-linolenic acid (C18:3) and reduced saturated fatty acids without compromising yield. In buffaloes, inclusion enhanced cheese quality and reduced energy footprint, though costs were higher. For small ruminants and growing animals, moderate inclusion (5–25% dry matter) improved intake, digestibility, and growth, while excessive replacement reduced feed intake or digestibility, likely due to rumen microbiota shifts. Additionally, hydroponic feeding reduced methane emissions in lambs, highlighting its environmental potential. Overall, hydroponic forage can serve as a sustainable complement to conventional feed resources, promoting resource efficiency and animal performance when properly integrated into balanced diets. Further studies should define optimal inclusion rates and evaluate economic and environmental trade-offs under different production systems. Full article

Corvids exhibit avoidance behaviour when foraging in the presence of potentially risky stimuli, yet it remains unclear how stimulus characteristics influence the strength of such responses. In this paper, we present wild-caught Large-billed Crows (Corvus macrorhynchos) with five conditions: no visual stimulus, a cardboard box (non-biological, stationary), an immobile owl decoy (biological, stationary), a continuous-motion owl decoy (biological, moving), and a sensor-activated-motion owl decoy (biological, moving, and sudden). Avoidance was quantified using feeding latency, landing frequency, total time spent in the feeding area, and food consumption. Compared with the condition with no visual stimulus, the presence of any visual stimulus elicited increased latency, indicating that crows detect and respond to objects near food. Among the four objects, the sensor-activated-motion owl decoy produced stronger avoidance responses of the crows than the non-biological and stationary object (cardboard box). This indicates that they evaluate not only the presence of an object but also its motion characteristics and/or perceived biological cues when adjusting their foraging behaviour. Although sample size and individual variation impose limitations, these findings suggest that both the presence of visual stimuli and/or the complexity of their appearance play key roles in shaping avoidance behaviour in corvids. 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

Mitigating enteric methane emissions through diet formulation remains a significant challenge in cattle nutrition. This study developed a system to evaluate the methane production potential of feeds, expressed as the effective ruminal methane production rate (eRMR, mL/g dry matter [DM]), using a discontinuous in vitro ruminal fermentation system using rumen fluid. Sixteen concentrate feeds and two forages were tested, with a reference diet (ryegrass straw:corn:corn gluten feed = 1:1:1) included in each batch to standardize conditions and account for associative effects among feeds. Test feeds were incubated with the reference diet in closed bottles under strictly anaerobic conditions. Methane and total gas production were measured at 2, 4, 6, and 24 h, and true dry matter digestibility was calculated after 6 and 24 h. For each batch, sample feed values were corrected and standardized using those of the reference diet. The eRMR value was calculated by integrating a differential equation with parameters incorporating ruminal digestion and passage dynamics. The test feed eRMR values ranged from 1.2 mL/g DM (soybean meal) to 56.7 mL/g DM (soybean hull), with the reference diet at 14.8 mL/g DM. Evaluation of feed eRMR using data from two in vivo studies demonstrated strong correlations between predicted diet-specific eRMR values and measured methane emissions from Hanwoo steers (r = 0.93 and 0.85). This system, incorporating rumen dynamics with a reduced sampling schedule, provides a precise and practical tool for predicting in vivo enteric methane production and optimizing diet formulations to mitigate methane emissions from cattle. Full article

In the present context of climate changes, multipurpose and stress-resistant crops tend to be widely grown in areas with severe environmental conditions, such as drought and saline-alkali land. Due to its effective adaptation to high-temperature dry conditions, Sorghum bicolor (L.) Moench is a highly resistant and versatile crop. Sorghum is cultivated as a grain, sweet stem, forage material, and broomcorn, and is a source of fuel, alcoholic and non-alcoholic beverages, and building materials. Sorghum could be part of an integrated circular economy due to its special manufacturing possibilities. Despite having plenty of beneficial properties, sorghum is not very popular all over the world. Thus, the main purpose of our study is to reveal its benefits and various manufacturing possibilities. Currently known more for being used as animal feed and for biofuel production, once popularized, sorghum could become an important vector of food security. The present study reviews the latest data, highlighting the potential of sorghum to develop new food products, noting the functional and health properties of sorghum in foods and the processing possibilities of sorghum-based products. Full article

Lolium perenne L. (perennial ryegrass) has various applications, including as a high-quality forage species for livestock feed; in seed mixtures used for revegetation of eroded or degraded areas as well as for lawns due to its resistance and rapid germination; for erosion control on slopes and areas with excessive steepness; for phytoremediation of soils contaminated with potentially toxic elements due to its ability to accumulate metals in its tissues; and as a cover crop to improve soil conditions and control erosion. Accordingly, L. perenne provides several ecosystem services, primarily related to soil stability, agriculture, and recreation. Climate change poses challenges for L. perenne, particularly heat and drought stress, which can reduce its yield and alter its geographical distribution. Climate change also impacts the interactions between L. perenne and its environment, affecting aspects like phenology (e.g., flowering time), carbon fixation, and overall resilience. However, the species’ significant genetic and endophyte-related variability may allow for adaptation. The aim of the present study was to assess the drought tolerance of three Bulgarian varieties of L. perenne, namely Harmoniya (diploid), Tetrany, and Tetramis (tetraploids). We performed induced drought stress under laboratory conditions and monitored its effect on plants in the early stages of growth and development. A variety-specific response was found regarding the effect of different concentrations of sucrose on seed germination, primary root and stem elongation (cm), fresh biomass accumulation (g), as well as on seedling vigor index and plant development. Field experiments and yield elements were also used to assess drought susceptibility and sensitivity to stress in a real environment. The tetraploid perennial ryegrass varieties Tetrany and Tetramis showed better germination, growth, and development in laboratory tests and had higher and more stable field productivity under both optimal and stress conditions than the diploid variety Harmoniya. Ploidy was the factor that characterize them as drought-tolerant genotypes under water-limited conditions, and its potential could be used in future breeding programs. Full article

Accurate prediction of forage digestibility is essential for efficient livestock management and feed formulation. This study evaluated the performance of machine learning (ML) models to estimate the in vitro digestibility of leaf and stem components of Brachiaria hybrid cv. Ipyporã, using three datasets composed of pasture management variables, chemical composition variables, and their combination. Artificial neural network (Multilayer Perceptron, MLP), decision trees (REPTree and M5P), Random Forest (RF), and Multiple Linear Regression (LR) were tested. The principal component analysis revealed that 61.3% of the total variance was explained by two components, highlighting a strong association between digestibility and crude protein content and an opposite relationship with lignin and neutral detergent fiber. Among the evaluated models, MLP, LR, and RF achieved the best performance for leaf digestibility (r = 0.76), while for stem digestibility the highest accuracy was obtained with the LR model (r = 0.79; MAE = 2.42; RMAE = 2.87). The REPTree algorithm presented the lowest predictive performance regardless of the input data. The results indicate that chemical composition variables alone are sufficient to develop reliable prediction models. These findings demonstrate the potential of ML techniques as a non-destructive and cost-effective approach to predict the nutritional quality of tropical forage grasses and support precision livestock management. Full article

A high salt environment seriously affects the physiological metabolism and yield of plants. Hordeum brevisubulatum (Trin.) Link has high biomass and important ecological, feeding and economic values, but its growth conditions have serious saline-alkali effects. The NHX gene family plays a vital role in regulating intracellular Na⁺/K⁺ balance, pH homeostasis, and vesicle and protein transport in plants. In this study, the HbNHX2 gene was cloned from Hordeum brevisubulatum and functionally characterized through phenotypic, physiological, and molecular analyses in transgenic tobacco. Expression profiling revealed that HbNHX2 was most abundant in spikes and least abundant in root tips, and the expression level was significantly induced under salt stress. Overexpression of HbNHX2 led to decreased malondialdehyde (MDA) and superoxide anion (O²⁻) levels, while it enhanced the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). Additionally, the levels of glutathione (GSH), soluble proteins, proline, and chlorophyll were also increased. Several stress-responsive genes, including CBL1, ERF2, BI-1, Cu/Zn-SOD, Mn-SOD, POD, GR1, KC1, TPK1, TIP, P5CS, BAS1, STN7 and LTP1, were significantly upregulated, while SERK3B was downregulated. These findings suggest that HbNHX2 enhances plant salt tolerance by maintaining osmotic balance, scavenging reactive oxygen species (ROS), and regulating stress-responsive gene expression. This study provides new insights into the molecular mechanism of salt tolerance in Hordeum brevisubulatum and lays a foundation for breeding salt-tolerant forage crops. Full article

Enteric methane (CH₄) emissions from ruminants are one of the major contributors to greenhouse gas emissions (GHG) from agriculture. We hypothesized that increasing levels of whole cottonseed (WCS) in diets decreases CH₄ production in ruminants fed low-quality forages without compromising feed digestibility. Dietary lipid supplementation, particularly with oilseeds such as WCS, has the potential to reduce enteric CH₄ production by altering rumen fermentation pathways. This study aimed to evaluate the effects of WCS inclusion in a tropical forage-based diet on in vitro gas and CH₄ production, fermentation characteristics, and in vitro dry matter digestibility (IVDMD). Five treatments were tested using guinea grass hay (GG) supplemented with 0, 12.5, 25, 37.5, and 50% of WCS (DM basis). Results after 48 h of incubation showed a quadratic response of total gas production with increasing WCS inclusion (p < 0.01), with the highest values observed at 12.5% and 25% WCS. Methane production from digested DM significantly reduced at 50% WCS inclusion (−10.66% respect to control; p = 0.02), suggesting a mitigation effect without detrimental impacts on IVDMD (p = 0.16), which remained unaffected across all treatments. No effects were found in initial or final pH (p = 0.98 and p = 0.89, respectively) or total protozoa count among treatments (p = 0.99). However, levels of 50% WCS inclusion exceed the recommended limit of fat in ruminant diets (>6% DM). Further in vivo validation trials are recommended to confirm these in vitro results and evaluate long-term impacts on animal performance and CH₄ emissions. This article is a revised and expanded version of Whole cottonseed as an alternative to mitigate in vitro methane emissions on low-quality forage-based diets. Presented at the International Research Symposium on Agricultural Greenhouse Gas Mitigation. From Research to Implementation. 21–24 October 2024, Berlin, Germany. Full article