Starch-protein interaction in the rumen of weaned dairy calves

Effects of Replacing Soybean Meal with Cottonseed Meal, Peanut Meal, Rapeseed Meal, or Distillers' Dried Grains with Solubles on the Growth Performance, Nutrient Digestibility, Serum Parameters, and Rumen Fermentation in Growing Lambs

Considering the frequently large price fluctuations for soybean meal, an alternative is the increased use of locally produced high-protein ingredients. The objective of this study was to evaluate the effects of the total replacement of soybean meal with different sources of protein on the growth performance, nutrient digestibility, serum parameters, rumen fermentation parameters, and bacterial communities in growing lambs. Sixty sheep with similar body weights (38.46 ± 0.71 kg) were distributed to one of five treatments: soybean meal (SBM); cottonseed meal (COM); peanut meal (PEM); rapeseed meal (RAM); and distillers' dried grains with solubles (DDGS). The experiment lasted 62 days with a 10-day adaptation period and a 52-day growing period. The results indicated that the body weight and average daily gain were not affected by different protein sources (p > 0.05), but the dry matter intake of the SBM group was lower than that of the other groups (p < 0.05); otherwise, the feed efficiency was higher (p < 0.05). The digestion of dry matter was higher in the SBM, COM, and RAM groups than in the DDGS and PEM groups (p < 0.05). Meanwhile, compared to the other groups, the SBM group had the highest digestion of gross energy and crude protein (p < 0.05). In addition, the concentration of glutathione peroxidase was highest in the SBM group (p < 0.05). Regarding the rumen fermentation, the SBM group had the highest concentration of NH3-N (p < 0.05). The rumen bacterial community was not affected by treatments (p > 0.05). In conclusion, the total replacement of soybean meal with cottonseed, peanut, rapeseed, or DDGS reduced digestibility but did not impact the body weight or average daily gain of growing lambs and had no effect on the immune function and rumen bacterial community; thus, they can be used to substitute the soybean meal.

Effects of corn grain processing and protein source on calf performance, rumen fermentation, and blood metabolites

The objective of this study was to investigate the effects of the interaction between corn grain processing and protein source on feed intake, growth performance, rumen fermentation, and blood metabolites of dairy calves. Seventy-two 3-day-old Holstein calves with an initial weight of 39.1 ± 3.24 kg were randomly assigned (n = 12 calves (6 male and 6 female) per treatment) to a 2 × 3 factorial arrangement of treatments with the factors of physical form of the corn grain [coarsely ground (CG) and steam-flaked (SF)] and protein type [canola meal (CAN), canola meal + soybean meal (CASY), and soybean meal (SOY)] were assigned. The study showed a significant correlation between corn grain processing method and protein source on calf performance, including starter feed intake, total dry matter intake (DMI), body weight, average daily gain (ADG), and feed efficiency (FE). The CG-CAN and SF-SOY treatments resulted in the highest feed intake and DMI in the post-weaning and total period, respectively. Interestingly, corn processing did not affect feed intake, ADG, and FE, but the highest ADG was observed at SF-SOY and CG-CAN. In addition, the interaction between corn processing method and protein source improved FE in calves fed CG-CAN and SF-SOY during the preweaning period and throughout the period. Although skeletal growth parameters were unchanged, calves fed SOY and CASY had greater body length and withers height than calves fed CAN during the preweaning period. Rumen fermentation parameters were also not affected by the treatments, except that calves fed CAN had a higher molar proportion of acetate than calves fed SOY and CASY. Corn grain processing and protein source did not affect glucose, blood urea nitrogen (BUN), or β-hydroxybutyrate (BHB) concentrations, except for the highest blood glucose level observed in the CAN treatment and the highest BUN level observed in the preweaned calves fed SOY. However, a two-way interaction was observed for BHB concentration, suggesting that ground corn grain resulted in higher BHB concentration during the preweaning and postweaning periods than steam-flaked corn. In summary, it is recommended to incorporate canola meal with ground corn or soybean meal with steam-flaked corn in calf starters to enhance calf growth.

Average Daily Gain in Lambs Weaned at 60 Days of Age Is Correlated with Rumen and Rectum Microbiota

Colonization of gastrointestinal microbiota in mammals during early life is vital to host health. The objective of this study was to investigate whether lambs with high and low ADG have a different rumen and rectum microbial community. Thus, we investigated potential relationships between rumen and rectum microbiota and average daily gain (ADG) in weaned lambs. Sixteen lambs with similar body weights (7.63 ± 1.18 kg) were selected at 30 days of age. At 60 days of age, lambs were weaned, and ADG was calculated from 60 to 90 days. Then, two groups were generated: higher ADG (HG, 134.17 ± 13.48 g/day) and lower ADG (LG, 47.50 ± 19.51 g/day). Microbiota was evaluated at 30, 60, and 90 days of age. The final live weight and ADG at 90 days of age was higher (p < 0.05) in the HG group compared to the LG group. The maturity of bacterial and fungal communities was increased (p < 0.05) in the HG group for the 30 days vs. 90 days comparison and 60 days vs. 90 days comparison. Linear discriminant analysis effect size (LEfSe) analysis revealed a total of 18 bacterial biomarkers that are ADG-specific in the rumen and 35 bacterial biomarkers in the rectum. Meanwhile, 15 fungal biomarkers were found in the rumen and 8 biomarkers were found in the rectum. Our findings indicated that ADG is related to the rumen and rectum microbiota in lambs.

Diets containing processed barley grain as a potential rumen bypass starch source enhance productive responses of lactating Holstein dairy cows

Effect of diets containing untreated or processed barley grain [treated with sugar beet pulp extract (SBPE) or double sulphate of aluminium and potassium (ALUM)] and different levels of rumen undegradable crude protein (RUP) on production, rumen fermentation and blood metabolites of lactating Holstein cows were investigated. Untreated soybean meal (SBM) or xylose protected 'Yasminomax soy® (YAS)' was included to represent a low (LR, 4.2% DM) and high (HR, 5.4% DM) RUP diets, respectively. Experimental diet was as follows: (a) untreated barley grains with high RUP (HRCON); (b) untreated barley grains with low RUP (LRCON); (c) ALUM-treated barley grain with high RUP (HRAL; (d) ALUM-treated barley grain with low RUP (LRAL); (e) SBPE-treated barley grain with high RUP (HRSE); and (f) SBPE-treated barley grain with low RUP (LRSE). The experiment was conducted as a completely randomized design with lactating dairy cows (n = 36) averaging 215 ± 18 days in milk, milk yield 31.7 ± 5.8 kg/day, 620 ± 61 kg body weight. Diets containing processed barley grain increased feed intake, while decreased both rumination and eating (p < 0.001). Feed intake of dairy cows on Low RUP and High RUP were 23 and 24 kg/day, respectively (p < 0.01). Daily production of milk fat, protein, lactose and total solids was improved when the processed barley grain was included in the diets (p < 0.05). Present study pinpointed that the inclusion of the processed barley grain in diets might improve production indices of dairy cows.