Effects of protein grass hay as alternative feed resource on lamb's fattening performance and meat quality.

Protein grass hay (PGH) was used as a new feed source for lambs to study its effect on fattening performance and meat quality. Fifty-six male lambs were allotted to four experimental groups and fed for eight weeks either alfalfa hay (AH)-based diet (control) or diets in which AH was replaced with 33 %, 66 %, or 99 % PGH. The inclusion of PGH did not affect final body weight, dry matter intake, average daily gain, feed conversion ratio, or carcass weight. Moreover, substituting AH with PGH at any level did not influence the ruminal fermentation or serum biochemical parameters, meat color, water holding capacity, shear force, or amino acid profile. However, relative liver weight was increased with 66 % substitutions. Furthermore, replacing 99 % AH with PGH decreased the meat's pH at 24 h. Higher levels of C18:3n-3, C20:5n-3, and total n-3 PUFA and a lower ratio of n-6: n-3 PUFA were also observed in meat from lambs fed PGH at 99 %. These findings suggest that PGH could be incorporated into the lamb's diet up to 99 % without compromising fattening performance and body health while improving their meat n-3 PUFA deposition.

Initial timing of alfalfa hay supplementation manipulates blood parameters, rumen gene expression, and epithelial microbiota in pre-weaning lambs.

The present study aimed to investigate the impact of initiating alfalfa supplementation at either 14 d or 42 d of age on growth performance, blood parameters, rumen tissue gene expression, and epithelial microbiota in pre-weaning lambs. A total of 42 seven-day-old male Hu lambs (3.88 ±â€…0.92 kg) were selected for this study. After 7 d of adjustment period, 6 lambs were slaughtered at 14 d of age to establish a baseline control. The remaining 36 lambs were randomly allocated to 2 treatment groups, every 3 lambs were considered a unit, including fed milk replacer, starter pellets, and either alfalfa hay fed at 14 (EAF) or 42 d of age (LAF). Body weight and feed intake were recorded for lamb until 70 d of age. Blood samples, rumen tissue samples, and epithelial microbiota samples were collected from the lambs at 42, 56, and 70 d of age. The results indicated that average daily gain, starter intake, and total dry matter intake were greater in the EAF group compared to the LAF group from 14 to 42 d of age (P < 0.01), but no significant differences from 43 to 70 d of age or during the entire trial. Treatment and age interactively affected the alfalfa intake (P = 0.02) from 43 to 70 d of age. The concentration of serum immunoglobulin A (IgA) (P < 0.01) and the expression of the rumen gene insulin-like growth factor-1 (P < 0.01) were greater in the EAF group compared to the LAF group at 42 d of age. Furthermore, the concentrations of alkaline phosphatase (P = 0.03), albumin (P < 0.01), total protein (P = 0.03), urea (P = 0.04), lipopolysaccharide (P < 0.01), ß-hydroxybutyric acid (P = 0.02), interleukin-1ß (IL-1ß) (P < 0.01), IL-4 (P < 0.01), and tumor necrosis factor-α (P < 0.01) were affected by age. The abundance of Prevotella was lower (P < 0.05), whereas Megasphaera (P < 0.05) was greater in the EAF group compared to the LAF group at 42 d of age. The early addition of alfalfa promotes rumen epithelial microbiota colonization. In conclusion, this study demonstrated that alfalfa provision at 14 d of age promotes growth performance in lambs, but this effect disappeared at 43 to 70 d of age. Moreover, provision of alfalfa at 14 d of age enhances the immune response, promotes rumen tissue cell proliferation, and affects dynamical changes of rumen epithelial microbiota. Meanwhile, our findings showed that the rumen undergoes significant physiological challenges during the transition from a liquid diet to a solid diet.

Recent studies have shown that in pre-weaning ruminants, the addition of alfalfa hay is beneficial for growth and rumen development. However, the effect of alfalfa supplementation timing on the growth of pre-weaning lambs remains still unclear. This study aims to explore the growth performance, blood parameters, rumen epithelial microbiota, and rumen tissue gene expression in response to alfalfa supplementation starting from either 14 d or 42 d of age in pre-weaning lambs. Our results indicate that alfalfa supplementation at 14 d of age could increase the average daily gain, starter intake, and total dry matter intake, but did not persist over the long term. When compared with the consumption of alfalfa starting at 42 d of age, starting to consume alfalfa at 14 d of age could improve immune response and promote rumen tissue cells proliferation. Furthermore, the supplementation of alfalfa, starting at 14 d of age, not only increased the abundance of Megasphaera, but also affected dynamical changes in the rumen epithelial microbiota. Additionally, our findings suggest that the rumen undergoes significant physiological challenges during the transition from a liquid diet to a solid diet.

On-farm harvest timing effects on alfalfa weevil across the Intermountain West region of the United States.

Alfalfa (Medicago sativa L.) is an economically important commodity in the Intermountain Western United States. A major concern for alfalfa producers in this region is the alfalfa weevil (Hypera postica Gyllenhal). Insecticide resistance development coupled with regulatory changes in pesticide use has resulted in renewed interest by producers in non-chemical control methods such as cultural control. One such cultural control method is early harvest, which consists of producers timing their harvests early in the season to decrease alfalfa weevil damage. This method is thought to be effective by exposing weevil larvae to adverse conditions before significant damage occurs. Still, early harvest can be difficult to employ because recommendations are often vague. To better understand how early harvest impacts both alfalfa weevils and their natural enemies and how producers are using this method across the Intermountain Western United States, we conducted a study in alfalfa production fields in Colorado, Montana, and Wyoming over three growing seasons. We determined that the timing of the initial alfalfa harvest spanned more than 1 month across fields, and alfalfa plant stage at harvest ranged from late vegetative to early bloom. Harvest was more impactful on reducing alfalfa weevil densities the earlier it was implemented. Removing windrows in a timely manner is likely useful to further decrease alfalfa weevil densities. Harvest timing was not associated with parasitism rates of alfalfa weevil, but higher parasitism rates were associated with lower post-harvest alfalfa weevil densities. This work has increased our understanding of early harvest in an on-farm setting and to improve recommendations for producers across the Intermountain Western United States.

Alfalfa supplementation timing changes the rumen archaeal and fungal community composition and colonization in pre-weaning lambs.

The establishment of the rumen microbiota plays an important role in the rumen development. However, little is known about the effects of alfalfa supplementation time on rumen microbiota establishment. Here, a total of 42 Hu lambs, seven-day-old, were chosen for the study. After a week of adjustment, six lambs were sacrificed to establish a baseline. The remaining 36 lambs were randomly split into two groups: one receiving alfalfa hay at 14 days (EAF), the other at 42 days (LAF), both groups received milk replacer and starter pellets. Introducing alfalfa at 14 days of age significantly improved total dry matter intake between 28 and 42 days (p = 0.04) and average daily gain from both 14 to 28 days (p = 0.04) and 28 to 42 days (p < 0.01), but this effect disappears from 56 to 70 days (p > 0.05). At 42 days, the abundances of Naganishia, Ascochyta, and Neosetophoma in the EAF group were significantly higher (p < 0.05) than those in the LAF group (17.8% vs. 3.97, 10.89% vs. 1.77, and 1.27% vs. 0.09%, respectively). At 56 days, the abundances of Ascochyta, Wallemia, and Aspergillus in the EAF group were significantly lower (p < 0.05) than in the LAF group (3.53% vs. 16.40, 8.78% vs. 18.89, and 2.14% vs. 4.69%). At 70 days, Aspergillus abundance in the EAF group was significantly higher (p < 0.05) than in the LAF group (2.69% vs. 0.85%). The LEfSe analysis showed that Methanobrevibacter_smithii was the archaeal biomarker at 14 days in both groups. Methanobrevibacter_sp_AbM4 was enriched at 56 days in the LAF group. Compared to the LAF group, the specific fungal biomarkers in the EAF group included Sporobolomyces and Bullera at 14 days, Naganishia, Didymella, Cleistothelebolus, and Alloleptosphaeria at 42 days, Ascochyta, Neoascochyta, and Alfaria at 70 days. Correlation analysis results showed strong patterns of association both within and between archaea and fungi, which were influenced by alfalfa supplementation time. In summary, alfalfa supplementation at 14 days of age promotes the growth performance of lambs before weaning, and alfalfa supplementation timing significantly affects rumen archaeal and fungal communities and dynamical changes.

Partially substituting alfalfa hay with hemp forage in the diet of goats improved feed efficiency, ruminal fermentation pattern and microbial profiles.

The use of hemp as a forage source in livestock diets has been less studied because bioactive residues in animal tissues may pose a risk to consumers. This study investigated the effects of partial substitution of alfalfa hay (AH) with hemp forage (HF) in growing goat diets on growth performance, carcass traits, ruminal fermentation characteristics, rumen microbial communities, blood biochemistry, and antioxidant indices. Forty Xiangdong black goats with body weight (BW) 7.82 ± 0.57 kg (mean ± SD) were grouped by BW and randomly assigned into one of the four treatment diets (n = 10/treatment) in a completely randomized design. The goats were fed ad libitum total mixed rations containing 60% forage and 40% concentrate (DM basis). The diets included control (CON; 60% AH and 40% concentrate), 55% AH and 5% HF (HF5), 50% AH and 10% HF (HF10), and 40% AH and 20% HF (HF20). Increasing the substitution of HF for AH linearly decreased (P < 0.01) DM intake and improved feed conversion efficiency. However, final BW, average daily gain, carcass traits, meat quality, and most blood biochemistry indices did not differ among treatments. The ruminal NH3-N concentration and blood urine nitrogen linearly increased (P < 0.01) with increasing substitution rate of HF, whereas the total volatile fatty acids concentration quadratically changed (P < 0.01). Substitution of AH with HF had no effect on the diversity and richness of ruminal microbes, though it linearly decreased (P = 0.040) Prevotella_1 and linearly increased (P = 0.017) Rikenellaceae_RC9_gut_group. The cannabinoids and/or their metabolites were detected in both ruminal filtrates (8) and plasma (4), however, no detectable cannabinoid-related residues were observed in meat. These results indicate that the HF could be used to partially substitute AH in goat diets, whereas the effects vary between substitution rates of HF for AH. Although no cannabinoid-related residues were detected in meat, the presence of cannabinoids residues in blood warrants further study of HF feeding to confirm the cannabinoids residues are not present in the animal products.

Ruminal microbiota-host crosstalks promote ruminal epithelial development in neonatal lambs with alfalfa hay introduction.

Ruminal microbiota is gradually established after birth, while microbiota maturation could be highly diverse because of varied solid dietary accessibility. However, how the ruminal microbiota accreted from postnatal hay diets alters rumen epithelial development, and how this affects animal health remains largely unknown. Here, neonatal lambs were introduced to starchy corn-soybean starter or corn-soybean starter + alfalfa hay (AH) to investigate the influences of early life ruminal microbiome on rumen epithelial development using integrated 16s rRNA sequencing-metagenome-transcriptome approaches. The results showed that AH introduction elevated average daily weight gain, rumen weight and volume, rumen epithelial papillae length, and rumen muscle layer thickness. Meanwhile, the relative abundance of fibrolytic bacteria (Christensenellaceae R-7 group, Prevotellaceae UCG-001, and Succinivibrio), acetate producer (Acetitomaculum and Mitsuokella), and propionate producer Succiniclasticum was increased in the rumen content by AH supplementation (P < 0.05). Moreover, AH introduction decreased the relative abundance of total CAZymes, CBM, and GH and increased the abundance of KO genes related to volatile fatty acid (VFA) generation in the rumen content. AH lambs had a higher relative abundance of Succiniclasticum, Megasphaera, Succinivibrio, and Suttonella (P < 0.05), while a lower relative abundance of Cloacibacillus, Desulfovibrio, Dialister, Intestinimonas, Parabacteroides, and Pseudoscardovia (P < 0.05) in the rumen epithelial samples. Furthermore, these alterations in ruminal microbial structure and function resulted in ruminal epithelial cell proliferation and development pathways activation. In summary, AH introduction benefited ruminal fiber degradation and VFA generation bacteria colonization and promoted ruminal epithelial development. These findings provide new insights into ruminal microbial-host interactions in the early life.IMPORTANCEWhile it is established that a fiber-rich diet promotes rumen development in lambs, further research is needed to investigate the precise response of rumen microbiota and epithelium to high-quality alfalfa hay. Here, we observed that the inclusion of alfalfa hay led to a discernible alteration in the developmental trajectory of the rumen. Notably, there was a favorable shift in the rumen's volume, morphology, and the development of rumen papillae. Furthermore, ruminal microbial structure and function resulted in ruminal epithelial cell proliferation and development pathways activation, collectively provide compelling evidence supporting the capacity of alfalfa hay to enhance rumen development and health through ruminal micrbiota-host crosstalks. Our findings elucidate the functional response of the rumen to alfalfa hay introduction, providing new insights into strategies for promoting healthy development of the rumen in young ruminants.

In vitro assessment of ruminal biohydrogenation of polyunsaturated fatty acids in diets with different types and levels of protected fat and diverse sources of fibre.

The objective was to assess the in vitro rumen fermentation characteristics, methane production, and biohydrogenation of unsaturated fatty acids of diets with two protected fat (PF) sources from soybean or linseed oil, two levels of PF (0 and 6%) and two forage sources (canola silage (CS) or alfalfa hay (AH)) in a factorial 2x2x2 completely randomised design. Only fatty acids content at final incubation was affected (P<0.05) by triple interaction, where C18:2 was highest with AH plus 6% soybean PF (4.41mg/g DM), while C18:3 was with CS plus 6% linseed oil protected (1.98mg/g DM). C18:2 cis-9 trans-11 had high concentration (308 mg/g DM; P<0.05) with AH plus 6% PF regardless PF type, and C18:1 trans-11 was higher with 6% PF than without PF (13.41 vs 7.89 mg/g DM). Cumulative methane production was not affected by treatments (0.9973 ± 0.1549 mmol/g DM; P>0.05). Gas production and in vitro NDF digestibility were lower with 6% PF of linseed than soybean (160.88 vs 150.97 ml; and 69.28vs 62.89 %, respectively P<0.05). With linseed PF the NH3-N concentration was highest in CS than AH (41.27 vs 27.95 mg/dL; P<0.05) but IVDMD had the opposite result (78.54 vs 85.04). In conclusion, although methane production was not affected and in vitro digestibility and gas production were reduced with linseed PF, the concentration of C18:3 and C18:1 trans-11 was increased, which could improve the lipid profile of milk. The negative effects on digestibility were less with AH than of CS regardless of PF type and level.

Effects of Leymus chinensis hay and alfalfa hay on growth performance, rumen microbiota, and untargeted metabolomics of meat in lambs.

Objective: The objective of this study was to compare the effects of Leymus chinensis hay and alfalfa hay as the roughage on the rumen bacterial and the meat metabolomics in lambs. Methods: Fourteen male lambs were randomly assigned to two dietary treatments (one group was fed with concentrate and Leymus chinensis hay; another was fed with concentrate and alfalfa hay) with seven replicates per treatment. The feeding experiment lasted for 60 days. Lambs were slaughtered at the end of the feeding experiment. Growth performance, carcass performance, and weights of various viscera were determined. The longissimus dorsi and rumen contents were collected for untargeted metabolomics and 16S rDNA amplicon sequencing analysis, respectively. Results: The lambs fed with alfalfa hay showed a significantly increased in average daily gain, carcass weight, dressing percentage, loin-eye area, and kidney weight. Feeding Leymus chinensis hay and alfalfa hay diets resulted in different meat metabolite deposition and rumen bacterial communities in the lambs. The relative abundance of phyla Fibrobacteres, Bacteroidetes, and Spirochaetes were greater in the Leymus Chinensis hay group, while, the relative abundance of Firmicutes, Proteobacteria, Fusobacteria, and Verrucomicrobia were greater in the alfalfa hay group. Based on untargeted metabolomics, the main altered metabolic pathways included alanine, aspartate and glutamate metabolism, D-glutamine and D-glutamate metabolism, phenylalanine metabolism, nitrogen metabolism, and tyrosine metabolism. Several bacteria genera including BF31, Alistipes, Faecalibacterium, Eggerthella, and Anaeroplasma were significantly correlated with growth performance and meat metabolites. Conclusion: Alfalfa hay improved growth performance and carcass characteristics in lambs. Leymus chinensis hay and alfalfa hay caused different meat metabolite deposition by modifying the rumen bacterial community. These findings will be beneficial to future forage utilization for sheep growth, carcass performance, and meat quality improvement.

Alfalfa hay substitution for wheat straw improves beef quality via rumen microflora alteration.

The use of high-quality roughage to improve beef quality has become an important issue in China, as the country has become the world's largest beef consumer. This study aimed to evaluate the effects of different forage qualities (wheat straw vs alfalfa hay) on Simmental crossbreed cattle's meat quality, rumen fermentation and microbiota. AHG (Alfalfa hay group) improved the ADFI (Average daily feed intake) and ADG (Average daily gain) of the beef cattle, meat-to-bone ratio and EE (Ether extract). The C18:3n3 and C20:3n3 composition of LD in AHG was significantly higher than WSG. An increase in the relative abundance of Firmicutes and a decrease in Bacteroidetes was observed. AHG resulted in higher relative abundance of Saccharomonospora, Streptomyces. A negative correlation between Treponema and muscle PUFA was noticed. Prevotella was negatively correlated with starch and sucrose metabolism. In conclusion, current study demonstrates that feeding alfalfa hay can raise meat quality by altering the rumen microbiota, providing valuable information for the application of alfalfa hay in beef cattle breeding.

Comparison of Nutritional Components, Ruminal Degradation Characteristics and Feed Value from Different Cultivars of Alfalfa Hay.

The objective of this study was to evaluate the effects of different cultivars of alfalfa hay, including American Anderson (AA), American Golden Empress (GE), China Zhongmu No. 1 (ZM1) and China Gongnong No. 1 (GN1), on conventional nutrient composition, rumen degradation characteristics and feed value. Four healthy Holstein cows (137 ± 14 days in milk, 2.40 ± 0.50 parity) equipped with permanent ruminal cannulas were examined for the nylon-bag technique. The alfalfa hay samples were incubated in the rumen for 0, 4, 8, 12, 24, 36, 48 and 72 h according to the "gradual in/all out" schedule to detect the ruminal nutrients' degradability. Our results showed that various cultivars of alfalfa hay from different planting regions had significant differences on nutrient contents, rumen degradability and feed value. For nutritional components of alfalfa hay, the highest dry matter (DM) content was found in GE and the lowest in GN1 (p < 0.001); however, GN1 had the greatest concentration of ether extract (EE, p = 0.01), Ca (p < 0.001) and the lowest Ash (p < 0.001). Additionally, the lowest neutral detergent fiber (NDF), acid detergent fiber (ADF) and highest starch contents were observed in AA and GE (p < 0.001). Meanwhile, the cultivar of ZM1 represented the highest NDF, ADF and Ash contents, in conjunction with minimal CP and P concentrations (p < 0.001). In terms of rumen degradation characteristics, the effective degradation rate (ED) of DM in GE and ZM1 was significantly higher than that in AA and GN1 (p = 0.013). The NDF effective degradation was lower in ZM1 than the other three cultivars (p = 0.002), and in addition ZM1 also showed lower CP and ADF effective degradation than GE (p < 0.001). As far as feed value was concerned, the cultivar of alfalfa hay imported from the US, including AA and GE, exhibited higher relative feed value (RFV) and relative forage quality (RFQ) than Chinese alfalfa based on ZM1 and GN1 (p < 0.001). In conclusion, the results suggested that the cultivar of GE exhibited greater rumen degradable characteristics and feed value, while ZM1 showed the opposite status.

The Effect of Oat Hay, Alfalfa Hay, and Their Combined Diets on the Morphology and Function of the Pancreas in Preweaning Yak Calves.

In this study, we used a combination of animal nutrition and nontargeted metabolomics to investigate the effects of feeding different sources forages rations on the morphology and function of the pancreas in preweaning yak calves, providing theoretical guidance and important references for the healthy and high-quality rearing of yak calves. At 45 days old, 21 yak calf males were divided into OP, AP, and AOP groups, with seven animals in each group, which were fed with oat hay, alfalfa hay, and mixed oat and alfalfa hay, respectively. Five calves from each group were selected randomly to slaughter after a pretest period of 21 days and the official period of 120 days, when the average daily feed intake reached 1 kg. During the test, the growth and pancreas weight of yak calves were recorded, and the morphology and function of the pancreas tissues were determined using tissue sectioning methods, enzyme-linked immunosorbent assay (ELISA) tests, and nontargeted metabolomics strategies. The results showed that the body weight and pancreatic organ index of yak calves in the AOP group were significantly higher than those of the AP and OP groups. Compared to the AP and OP groups, the AOP group had considerably lower ratios of the area of the pancreatic endocrine component and overall percentage of that section of the organ, and the AOP group increased pancreatic amylase activity and a higher concentration of growth inhibitor. The AP group had significantly higher levels of the differential metabolites L-ascorbic acid, spermidine, spermine, and dopaquinone in the glutathione, ß-alanine, and tyrosine metabolic pathways than the OP group. The AOP group had significantly lower levels of the differential metabolites spermine and phenylacetylglycine in the glutathione and phenylalanine metabolic pathways than the AP group. In summary, compared to feeding oat or alfalfa hay alone, combined feeding oat hay and alfalfa hay is more beneficial to promote the morphological and functional development of the pancreas in preweaning yak calves, so as to enhance the digestion and absorption of nutrients in the diet and maintain the positive regulation of blood glucose levels. This provides an important basis for the optimized forage supply of healthy and high-quality rearing in preweaning yak calves.

Effects of Different Roughage Diets on Fattening Performance, Meat Quality, Fatty Acid Composition, and Rumen Microbe in Steers.

This study aimed to evaluate different roughages on fatting performance, muscle fatty acids, rumen fermentation and rumen microbes of steers. Seventy-five Simmental crossbred steers were randomly divided into wheat straw group (WG), peanut vine group (PG) and alfalfa hay group (AG), with 5 replicates of 5 steers each. The results showed a highest average daily gain and lowest feed/gain ratio in AG group (P = 0.001). Steers fed alfalfa hay had the highest muscle marbling score and n-3 polyunsaturated fatty acid (PUFA), and also the rumen NH3-N and microbial protein (MCP) concentration among the three groups (P < 0.05). Correlation analysis showed that ruminal NH3-N and MCP were negatively correlated with muscle saturated fatty acid (SFA), while ruminal MCP was positively correlated with muscle PUFA and n-3 PUFA (P < 0.05). 16S rRNA analysis indicated that fed alfalfa hay decreased the abundance of Ruminococcaceae_UCG-001(P = 0.005). More importantly, muscle SFA deposition were positively correlated to the abundance of Ruminococcaceae_UCG-001 (P < 0.05), while the muscle PUFA and n-3 PUFA deposition were negatively correlated to it (P < 0.01). Therefore, alfalfa hay provides a better fattening effect on steers. Alfalfa rich in n-3 PUFA would reduce the abundance of Ruminococcaceae_UCG-001 involved in hydrogenation, increase the rumen protective effect of C18:3 n-3, which is beneficial to the deposition of muscle n-3 PUFA and PUFA.

Effect of Providing Environmental Enrichment into Aviary House on the Welfare of Laying Hens.

This study aimed to determine the effects of providing environmental enrichment materials­pumice stone and alfalfa hay­to laying hens in the aviary system. A total of 2196 40-week-old Hy-Line Brown laying hens were randomly allotted to three treatment groups: (1) no enrichment (control; CON), (2) enrichment with pumice stone (PS), and (3) enrichment with alfalfa hay (HAY). Each treatment comprised four replicates of 183 hens each, and four of the same materials were provided per replicate. The experiment lasted for 26 weeks. Feed and water were provided ad libitum. As a result, the PS and HAY groups demonstrated increased egg production (p < 0.001). The HAY group showed a reduced rate of mislaid eggs (p < 0.01) and produced low egg weight and pale-yellow yolk (p < 0.05). Both enrichment materials decreased blood creatinine (CRE) or lactate dehydrogenase (LDH) in the blood and resulted in a significantly lower corticosterone (CORT) level (p < 0.05). However, the feather condition scores for the laying hens were similar across all treatments (p > 0.05). In summary, although pumice stone and alfalfa hay are effective in alleviating stress and improving the production of laying hens, additional environmental improvement studies are needed to contribute to reducing pecking behaviors in poultry farming.

Analysis of Chemical Composition, Amino Acid Content, and Rumen Degradation Characteristics of Six Organic Feeds.

The current study was designed to investigate the chemical composition, amino acid content, and rumen degradation characteristics (nylon bag method) of six organic feeds to illustrate their feeding values. The feeds analyzed were: corn grain (CG), soybean cake (SC), wheat bran (WB), corn silage (CS), oat hay (OT), and alfalfa hay (AF). Our results showed that the contents of crude protein (CP) (47.46%) and ether extract (EE) (8.23%) in SC were highest. The contents of neutral detergent fiber (NDF) (65.00%) and acid detergent fiber (ADF) (39.16%) in OT were highest. The contents of total amino acid (TAA) (42.95%) and essential amino acid (EAA) (19.73%) in SC were highest. Among SC, WB, and CG, the effective degradation rate (ED) of dry matter (DM) is SC (87.89%) > WB (73.32%) > CG (64.25%); the ED value of CP is CG (82.37%) > WB (82.40%) > SC (60.47%). Among CS, OT, and AF, the effective degradation rate (ED) of DM is CS (72.68%) > OT (59.97%) > AF (58.89%); the ED value of CP is AF (76.46%) > CS (72.03%) > OT (71.99%). In conclusion, the chemical composition, amino acid content, and rumen degradation rate of SC and AF were better than those of the other four feeds.

Mixed oats and alfalfa improved the antioxidant activity of mutton and the performance of goats by affecting intestinal microbiota.

Oat hay and alfalfa hay are important roughage resources in livestock production. However, the effect of the mixture of oat hay and alfalfa hay on the meat quality of Albas goats is unclear. This study aimed to investigate the effects of feeding different proportions of oat hay and alfalfa hay on the growth performance and meat quality of Albas goats. Therefore, 32 goats were fed for 70 days and randomly divided into four treatment groups on the principle of similar weight: whole oat group (OAT), oat alfalfa ratio 3:7 group (OA73), oat alfalfa ratio 7:3 group (OA37) and whole alfalfa group (Alfalfa), with eight goats in each group. Daily feed intake records, feces, feed samples, and rumen fluid collection were made throughout the trial. The goats were weighed on the last day of the trial, and four goats per group were randomly selected for slaughter. Cecum contents, meat samples, and hot carcass weight were collected, and data were recorded. Furthermore, the relationship between the rumen and cecal microbes on performance and meat quality was clarified by analyzing the rumen and hindgut microbiomes. The results showed that feeding alfalfa could significantly reduce the daily weight gain of fattening goats. Compared with the highest group (OA37), the daily weight gain decreased by 19.21%. Although there was no significant change in feed intake in the four treatments, the feed conversion rate of the alfalfa group significantly decreased by 30.24-36.47% compared to the other groups. However, with the increased alfalfa content, MDA decreased significantly, T-AOC was up-regulated, and the antioxidant activity of the fattened goat meat fed with the high alfalfa group was significantly higher than that of the low alfalfa group. Notably, the abundance of Bacteroidales_unclassified and Clostridium were strongly correlated with T-AOC and MDA. Therefore, increasing the proportion of alfalfa in the diet can affect the antioxidant activity of goat meat by improving the gut microbiota, while an oat-hay mixture can improve the growth performance of livestock.

Forage quality and beef cow preference is affected by wrap type of conventional and reduced-lignin alfalfa round bales stored outdoors.

Storing hay outdoors can result in detrimental changes in forage quality. Additionally, alfalfa (Medicago sativa L.) cultivar may influence dry matter intake (DMI) and hay waste when feeding livestock. The objectives were to determine the effects of conventional or reduced-lignin alfalfa round bales stored outdoors and wrapped with plastic twine, net wrap, or B-Wrap on forage quality, beef cow preference, and hay waste. Round bales made from reduced-lignin (n = 12) or conventional (n = 12) alfalfa cultivars were baled and stored outdoors for 16 mo. Within each cultivar, four bale replicates were bound with plastic twine, net wrap, or B-Wrap. After storage, bales were fed in a switchback design with period confounded with alfalfa cultivar to 18 lactating Angus cows (Bos Taurus L.). The pairs had ad libitum access to three round-bale feeders where bales of each wrap type were placed for eight 48 h periods. Position of round bale wrap type was rotated according to a Latin Square arrangement. Bales were weighed and waste surrounding each feeder was collected at 24 and 48 h to calculate DMI and hay waste. Statistical significance was set at P < 0.05. Alfalfa cultivar did not impact any of the response variables (P > 0.05). At feeding, round bales wrapped in net wrap had greater (P < 0.015) moisture content (16.4%) compared with those wrapped with B-Wrap (12.8%). Neutral detergent fiber was lower (P = 0.03) in bales wrapped in B-Wrap (46%) compared with twine-tied bales (49%) while net wrapped bales were not different. Total digestible nutrients (P = 0.02), and relative feed value (P = 0.04) were lower in twine-tied bales compared with B-Wrap while net wrapped bales were not different. Twine (7.1 × 106 colony forming units [CFU]/g) and net wrap (4.7 × 106 CFU/g) bales had greater (P < 0.0001) mold counts than B-Wrap bales (4.8 × 104 CFU/g), while concentrations of other forage components and yeast counts were not different among wrap types (P > 0.05). Total DMI, and DMI during the first 24 h, were greater (P ≤ 0.032) for B-Wrap bales compared to twine-tied bales indicating preference for hay wrapped in B-Wrap; net wrapped bales were not different. Dry matter intake in the first 24 h was negatively associated with the mold count (r = -0.52; P = 0.02), and hay waste was not affected by wrap type (P > 0.05). These results confirm that wrap type affected forage quality and mold counts, which in turn influenced beef cattle preference of round bales stored outdoors.

Selenium biofortified alfalfa hay fed in low quantities improves selenium status and glutathione peroxidase activity in transition dairy cows and their calves.

The hypothesis of the study was that feeding a relatively low amount of Se biofortified alfalfa hay during the dry period and early lactation would improve selenium status and glutathione peroxidase activity in dairy cows and their calves. Ten Jersey and 8 Holstein primiparous dairy cows were supplemented with Se biofortified (TRT; n = 9) or non-biofortified (CTR; n = 9) alfalfa hay at a rate of 1 kg/100 kg of BW mixed with the TMR from 40 d prior parturition to 2 weeks post-partum. Se concentration in whole blood, liver, milk, and colostrum, the transfer of Se to calves, and the glutathione peroxidase (GPx) activity were assessed. TRT had 2-fold larger (P < 0.05) Se in blood v. CTR that resulted in larger Se in liver and colostrum but not milk and larger GPx activity in plasma and erythrocytes but not in milk. Compared to CTR, calves from TRT had larger Se in blood but only a numerical (P = 0.09) larger GPx activity in plasma. A positive correlation was detected between Se in the blood and GPx activity in erythrocytes and plasma in cows. Our results demonstrated that feeding pregnant primiparous dairy cows with a relatively low amount of Se-biofortified alfalfa hay is an effective way to increase Se in the blood and liver, leading to greater antioxidant activity via GPx. The same treatment was effective in improving Se concentration in calves but had a modest effect on their GPx activity. Feeding Se biofortified hay increased Se concentration in colostrum but not in milk.

Increasing roughage quality by using alfalfa hay as a substitute for concentrate mitigates CH4 emissions and urinary N and ammonia excretion from dry ewes.

Twelve Hu sheep × thin-tail Han crossbred dry ewes with an average body weight of 32.6 ± 0.68 kg and an age of 3 years were arranged in a 3 × 3 Latin square design, with each experimental period of 24 d to evaluate the effect of substituting alfalfa hay in a portion of concentrate on nutrient intake, digestibility, N utilisation efficiency and methane emissions. The ratios of corn straw to alfalfa to concentrate for 3 diet treatments were 60:0:40, 60:15:25 and 60:30:10, respectively. Intake and digestibility were measured for each of the ewes, which were housed in individual metabolism crates for 6 d after an adaptation period of 14 d, and the feed was offered at 1.2 MEm to ensure approximately 10% orts. Methane emissions were determined in a respiration chamber for 2 consecutive d. An increase in the levels of alfalfa as a substitute for concentrate significantly increased the roughage, NSC and ADF intake and faecal N output as a proportion of N intake and manure N output. Furthermore, this increase in alfalfa input levels decreased DE, ME and N intake; nutrient digestibility; DE/GE, ME/GE and CH4 emissions per day; CH4 output expressed as a portion of the DM, OM and GE intake; and urinary N and ammonia N output, especially between extreme treatments. Alfalfa input levels had no effect on the BW, DM and GE intake; the EB or EB/GE intake; and the retained N. This study indicated that increasing alfalfa input as a substitute for concentrate could significantly decrease the digestibility, CH4 emissions and urinary N and NH4 + -N outputs; and shift the N excretion from urine to faeces; and could sustain a similar DM intake.

Substituting corn silage with reconstituted forage or nonforage fiber sources in the starter diets of Holstein calves: effects on performance, ruminal fermentation, and blood metabolites.

We examined the effects of replacing corn silage (CS) with reconstituted alfalfa hay (AH) or beet pulp (BP) in the starter diet on the nutrient intake and digestibility, growth performance, rumen fermentation characteristics, selected blood metabolites, and health status in Holstein dairy calves. Newborn female calves (n = 54; 3 d of age; 39.8 ± 1.36 kg BW) were assigned randomly to 3 groups receiving starter diets containing CS [10% dry matter (DM) basis; CS diet) and reconstituted AH (10% DM, RAH diet) or BP (10% DM; RBP diet). The starter diets had the same nutrient composition and DM content. The calves were weaned on day 50 and the study continued until day 70. Nutrient intake, body weight (at weaning and at the end of the study), daily weight gain, feed efficiency, and body measurements (including heart girth, withers height, body length, body barrel, hip height, and hip width) were not affected by the diet (P > 0.05). Health-related variables including rectal temperature, fecal score, and general appearance score were not influenced by the diets (P > 0.05). During the postweaning period, apparent total tract digestibility of DM, organic matter, and crude protein were higher for RBP (P = 0.001); however, digestibility of neutral detergent fiber was lower in RAH compared with CS or RBP (P = 0.001). Daily amount of nutrient digestibility did not change across the diets (P > 0.05). Rumen fluid pH and total volatile fatty acid concentration and profile were not different across the diets after weaning (P > 0.05). Calves fed RAH or RBP had higher blood concentration of ß-hydroxy butyric acid compared with CS only before weaning (P = 0.03). Blood albumin concentration was higher for RBP compared with CS or RAH during the preweaning (P = 0.006) and overall (P = 0.005) periods; however, it was lower for CS compared with RBP after weaning (P = 0.03). Concentration of other blood variables including glucose, blood urea N, total protein, and globulin did not change across the diets (P > 0.05). Calves, in general, were healthy, and replacing CS with RAH or RBP in the starter diet had no beneficial effect on their feed intake or growth performance indicating that CS and reconstituted AH or BP can be used interchangeably in dairy calf starter diets until 70 d of age, allowing dairy producers more choices in selecting the feed ingredients.

Lactation performance and rumen fermentation in dairy cows fed a diet with alfalfa hay replaced by corn stover and supplemented with molasses.

OBJECTIVE: The objective of current study was to investigate the lactation performance and rumen fermentation characteristics of dairy cows fed a diet with alfalfa hay replaced by corn stover but supplemented with molasses. METHODS: Sixteen Holstein cows in mid-lactation were randomly assigned to 1 of 2 dietary treatments: i) alfalfa based diet (AH), and ii) corn stover based diet supplemented with molasses (CSM). The experiment was conducted according to a 2×2 crossover design with 22-d each period, consisting of 17 d for adaptation and 5 d for data and samples collection. RESULTS: Dry matter intake and milk yield were higher for cows fed AH than CSM (p<0.01). Milk protein content and nitrogen conversion were higher (p<0.05), while milk urea nitrogen was lower (p<0.01) for cows fed AH than CSM-fed cows. Contents of milk total solids, fat and lactose were not different between two groups (p>0.10). Total rumen volatile fatty acid concentration tended to be higher (p = 0.06) for cows fed AH than CSM-fed cows. Molar proportion of acetate was lower (p = 0.04), but valerate was higher (p = 0.02) in cows fed AH than CSM-fed cows. Rumen concentration of propionate, and isobutyrate, and ratio of acetate to propionate tended to be different (p<0.10) between two groups. The feed cost per kilogram of milk was lower in CSM than AH (p<0.01). No differences were found in feed efficiency and most plasma parameters tested (p>0.10). CONCLUSION: In comparison with AH diet, CSM diet could be fed to dairy cows without negative effect on feed efficiency, ruminal fermentation, but economically beneficial, indicating that CSM could be an alternative choice for dairy farms instead of AH to feed mid-lactation dairy cows.