Analysis of the relationship between energy balance and properties of rumen fermentation of primiparous dairy cows during the perinatal period.

Short-chain fatty acids (SCFAs) produced in the rumen are key factors affecting dairy cows' energy balance (EB). This study aimed to quantitatively evaluate the effects of SCFAs production on EB in dairy cows. Primiparous dairy cows were divided into high non-esterified fatty acid (NEFA; group H) and low NEFA (group L) groups based on their blood NEFA levels at week 3 postpartum, which served as an indicator of EB.

Effect of residual methane emission on physiological characteristics and carcass performance in Japanese Black cattle.

This study investigated the physiological characteristics and carcass performance associated with residual methane emissions (RME), and the effects of bull differences on CH-related traits in Japanese Black cattle. Enteric methane (CH) emissions from 156 Japanese Black cattle (111 heifers and 45 steers) were measured during early fattening using the sniffer method. Various physiological parameters were investigated to clarify the physiological traits between the high, middle, and low RME groups.

Assessing the impact of three feeding stages on rumen bacterial community and physiological characteristics of Japanese Black cattle.

In Japan, Japanese Black cattle, known for their exceptional meat quality owing to their abundant intramuscular fat, undergo a unique three-stage feeding system with varying concentrate ratios. There is limited research on physiological and rumen microbial changes in Japanese Black cattle during these stages. Therefore, this study aimed to examine Japanese Black steers in these three stages: early (T1, 12-14 months), middle (T2, 15-22 months), and late (T3, 23-30 months).

Effects of a low-protein diet supplemented with essential amino acids on egg production performance and environmental gas emissions from layer-manure composting in laying hens in the later laying period.

We fed 330-545 day-old laying hens (later laying period) a low-protein diet supplemented with essential amino acids (LPS) and composted their manure. We then investigated the laying performance of the hens, the nitrogen balance and emission of nitrous oxide (N O), methane (CH ), and ammonia (NH ) from the composting, and several characteristics of the finished compost. There were no significant differences in the egg-laying rate, egg mass, egg weight, proximate compositions in egg yolk and egg white, or feed intake between the laying hens fed a Control diet (Cont) and those fed the LPS diet.