The physiological dissimilarities of Holstein dairy cows with different milk yields

Abstract

Background Even if breed, parity, dietary and environmental management are same, dairy cows still have notable differences in milk yield that may be underpinned by physiologic differences. Objectives This study aimed to investigate the physiological dissimilarities of dairy cows with different milk yields. Methods Thirty cows were sorted into high milk‐yielding cows (group H: 58.93±2.31 kg/day), moderate milk‐yielding cows (group M: 44.99±0.54 kg/day), and low milk‐yielding cows (group L: 24.99±6.83 kg/day) according to milk yield. Blood was collected and serum parameters were assessed. Rumen fluid was collected for the evaluation of rumen fermentation parameters (RFPs) and bacterial community composition (BCC). Results Serum prolactin, growth hormone, glutathione peroxidase, immunoglobulin A and non‐esterified fatty acid had a significantly positive correlation with milk yield ( p < 0.05), whereas serum glucagon and total antioxidant capacity had a significantly negative correlation with milk yield ( p < 0.05). The concentration of valeric acid and the ratio of acetic acid to propionic acid in the rumen fluid in group H was significantly lower than that in group L ( p < 0.05). The concentration of acetic acid and butyric acid in group H was significantly lower than that in groups M and L ( p < 0.05). The relative abundances of Ruminococcaceae_NK4A214 _group, Prevotella_1 , Rikenellaceae_RC9_gut_group , Christensenellaceae_R‐7_group , Muribaculaceae , and Ruminococcus_2 were negatively correlated with milk yield, whereas the relative abundance of Succinivibrionaceae_UCG‐001 , Lachnospiraceae_NK3A20_group, Shuttleworthia and Dialister were positively correlated with milk yield ( p < 0.05). Conclusions This study indicates that dairy cows with different milk yields have clear divergence in serum indicators, RFPs, BCC and rumen microbial metabolism.

Capsaicin as a Dietary Additive for Dairy Cows: A Meta-Analysis on Performance, Milk Composition, Digestibility, Rumen Fermentation, and Serum Metabolites

“…Likewise, in Holstein calves [49] and non-ruminants [11,14], supplementation with CAP increases the serum concentration of immunoglobulins A (IgA), growth hormone (GH), glutathione peroxidase (GPX), and superoxide dismutase (SD). Similar effects of CAP consumption in dairy cows could be related to the observed increases in MY and FE since a recent study [50] reported that serum levels of IgG, GH, SOD, and CAT are positively correlated (r between 0.56 and 0.64) with MY and FE in dairy cows.…”

“…Likewise, the lack of changes in ruminal NH 3 -N concentration explains the lack of changes observed in MUN because these two parameters have a positive relationship [55]. Likewise, Dong et al [50] indicated that serum BHB levels are mainly used to diagnose ketosis in dairy cows. Therefore, in the current study, the lack of changes detected in BHB suggests that CAP does not modify the incidence of ketosis.…”

Mechanistic insights into rumen function promotion through yeast culture (Saccharomyces cerevisiae) metabolites using in vitro and in vivo models

“…Serum was subsequently collected and stored at −40°C for future analysis. Serum levels of growth hormone (GH), cortisol, insulin (INS), and leptin (LEP) were analyzed using a commercial sheep enzyme-linked immunosorbent assay kit (Shanghai Enzyme-Linked Biotechnology Co. Ltd., Shanghai, China; Dong et al, 2022 ; Zhao et al, 2024 ). Quantitative colorimetric kits (Nanjing Jiancheng Bioengineering Institute, Nanjing, China) were used to determine the concentration of glucose (GLU, Vieira et al, 2010 ).…”