The objective of this study was to evaluate the effect of supplying ruminally-protected lysine (RPL), methionine (RPM), or the two in combination (RPML) to transition dairy cows on the immunity and performance of their offspring. Eighty heifer calves (n = 20 calves per group) were assigned to four treatments based on their dam diet; basal diet (CON), a basal diet with lysine [RPL, 0.33% of dry matter (DM)], a basal diet with methionine (RPM, 0.16% DM), or with the combination (RPML). Calves were fed colostrum from their dams within 2 h of birth. Calves were then fed milk only (d 2–22), a combination of milk and milk replacer (d 23–25), and milk replacer (d 25–60). Starter feed was fed to the calves twice daily after liquid feeding. Calves blood samples were collected after calving on 0, 12, 24, and 48 h and 5 and 7 d after birth. Data were analyzed by SAS software v9.4. Providing ruminally-protected amino acids (RPAA) to transition cows improved colostrum quality compared to the CON (Brix; P < 0.01). Serum total protein concentrations were higher in calves from supplemented cows than in calves from unsupplemented cows (P < 0.01). Calves born to dams in the RPM, RPL, and RPML groups had higher plasma immunoglobulin G (IgG) concentrations 0, 12, 24, and 48 h and 7 d after birth than those born to dams in the CON group (P < 0.05). The percentage of calves with adequate passive immunity transfer was increased with RPM and RPL or the two in combination (P < 0.01). However, there was no difference in the percentage of calves with adequate passive immunity transfer between the RPM and RPL groups (P = 0.21). Calves from cows that receive supplemental RPAA have a greater average daily gain (ADG) than those born to cows in the CON group (P < 0.01). These results indicate that maternal supplementation with RPM or RPL or the two in combination during the periparturient period could be an alternative strategy to improve the performance of calves, especially in accelerated growth programs in calves. Copyright © 2021 Wang, Elsaadawy, Wu and Bu.
Tag: amino acids
Nutritional and medicinal benefits of Oyster (Pleurotus) mushrooms: a review
Pleurotus mushrooms are the third largest commercially produced and the second most important cultivated mushroom in the world, consisting of about 539 species. This comprises 25% of total world production of cultivated mushrooms. Pleurotus mushrooms possess various nutritional and medicinal values. The fruitbodies of Pleurotus are rich in unique flavor and nutrients such as carbohydrates, protein, vitamins, minerals and dietary fibers. Bioactive compounds such as lectin, proteoglycans, laccase, lovastatin, phenols and uridine present in Pleurotus have shown some anti-tumor, anti-cancer, anti-bacterial, anti-fungal, anti-viral, anti-inflammatory, genoprotective, anti-oxidant, immuno-modulatory, anti-diabetic, anti-allergic, antimitogenic, anti-hypertensive and anti-hypercholesterolemic properties. The major nutritional and medicinal benefits of important Pleurotus species are discussed in the present review.
Suppression of amino acid and oligopeptide mineralization by organic manure addition in a semiarid environment
The rapid mineralization of organic nitrogen (ON) in semiarid soils frequently results in large N losses, reduced crop yields, and environmental pollution. The addition of manures to soil has the potential to promote microbial growth, increase N immobilization, reverse the decline in soil organic matter, and enhance soil quality. In this study, three contrasting organic manures were used to determine their influences on amino acid and oligopeptide dynamics in soil (as key component of the soil ON‐cycle) as well their effects on the size of the microbial biomass and N immobilization. Laboratory incubation experiments were set up with soil obtained from experimental field trial sites for growing maize. Treatments included soil amended with either poultry manure (PM), farmyard manure, pressmud, or unamended (control). Radio‐ and stable‐isotope (14C–15N) techniques were used to assess ON mineralization, immobilization, and leaching using the amino acids alanine and valine as well as the oligopeptides trialanine and valine–proline–proline as model substrates. Quantitative polymerase chain reaction was used to determine soil bacterial biomass. The results showed that all manures increased microbial growth and total soil amino acids as well as protein content. Greater immobilization and subsequently lower mineralization and leaching were also observed in the manure‐amended soils, with this being most pronounced in the PM treatment. The application of PM also enhanced the half‐lives of the ON compounds in soil and increased the size of the bacterial biomass. Overall, our findings indicate that manure amendments, particularly PM, can help promote more efficient ON cycling in semi‐arid ecosystem by controlling N mineralization, reducing amino acid leaching, and elevating oligopeptide immobilization.