Effects of rumen-protected folic acid on ruminal fermentation, microbial enzyme activity, cellulolytic bacteria and urinary excretion of purine derivatives in growing beef steers

Effects of rumen‐protected folic acid and dietary protein level on growth performance, ruminal fermentation, nutrient digestibility and hepatic gene expression of dairy calves

“…Recent studies demonstrated that the positive response of nutrient intake to the increased CP level could be observed only when dietary protein content was deficient in heifers (Detmann, Valente, Batista, & Huhtanen, ) or beef cattle (Silva, Pereira, Silva, Valadares Filho, & Ribeiro, ). The unchanged DM intake with RPFA supplementation was consistent with the findings of Wang et al, () in steers. The higher ADG was due to an improved nutrient utilization, as indicated by the lower FCR, and was also associated with a positive response of protein synthesis metabolism with increasing dietary CP level or RPFA supplementation.…”

“…Ruminal pH ranged from 6.51 to 6.73 and was optimum for cellulolytic bacteria growth and feed fibre degradation (Wales, Kolver, Thorne, & Egan, ). The higher ruminal total VFA concentration and acetate molar proportion indicated that cellulolytic bacteria growth and enzyme activity were stimulated with increasing dietary CP level or RPFA supplementation, as observed in the previous studies (Wang et al, ,). The degradation products of feed protein, including peptides, amino acids, ammonia N, isobutyrate and isovalerate, were essential for ruminal microbial growth (Granzin & Dryden, ).…”

“…Therefore, supplementation of RPFA spared amino acids for protein synthesis by improving the transfer efficiency of one‐carbon unit (Girard et al, ; Graulet et al, ), and causing the positive response of blood total protein and albumin. Additionally, the higher microbial protein synthesis (Wang et al, , ) also contributed to the increase in blood total protein and albumin with RPFA supplementation. The higher blood folate and lower Hcy indicated that dietary FA was absorbed efficiently, and more Hcy was transformed into cysteine and methionine to participant in protein synthesis (Girard et al, ).…”

“…Given the higher ruminal degradation rate (0.97) of supplementary FA (Santschi, Berthiaume, Matte, Mustafa, & Girard, ), a rumen‐protected folic acid (RPFA) supplements with the degradability of 0.304 was used in the current study. Moreover, previous studies demonstrated that ruminal total volatile fatty acids (VFA) concentration, nutrient degradability, cellulolytic bacteria abundance and enzyme activity increased with RPFA supplementation in steers (Wang et al, , ).…”

Effects of rumen‐protected folic acid and rumen‐protected sodium selenite supplementation on lactation performance, nutrient digestion, ruminal fermentation and blood metabolites in dairy cows

“…Considering the higher degradability of FA (0.97), rumen‐protected folic acid (RPFA) was a desirable FA supplement, which provided FA for microbial growth and allowed most of the FA to escape from the rumen . Our previous studies observed that supplementation of RPFA increased ruminal cellulolytic bacteria abundance, enzyme activity and total volatile fatty acid (VFA) concentration . Moreover, milk yield, milk protein concentration and nutrient digestibility increased with RPFA supplementation in dairy cows …”