학술논문
Effects of waste milk feeding on rumen fermentation and bacterial community of pre-weaned and post-weaned dairy calves
Document Type
article
Author
Source
Frontiers in Microbiology, Vol 13 (2023)
Subject
Language
English
ISSN
1664-302X
Abstract
The objective of this study was to investigate the effect of waste milk with antibiotic residue on rumen fermentation and rumen bacterial composition of dairy calves during pre-weaned and post-weaned periods. A total of 24 Holstein male calves (43.4 ± 0.93 kg body weight, mean ± standard error) were allocated into four blocks based on birth date. Dairy calves were supplied 100% milk replacer (MR, n = 8), 50% milk replacer mixed with 50% waste milk (MM, n = 8), or 100% waste milk (WM, n = 8). Ruminal samples were collected at 49 and 63 days of age and then subjected to determinations of pH value, volatile fatty acids (VFA), ammonia nitrogen (NH3–N) and 16S rRNA gene amplicon sequencing. The results showed that feeding WM had no effect on the pH value, the concentrations of VFA (acetic acid, propionic acid, butyric acid, isovaleric acid, valeric acid), and NH3–N in dairy calves compared to feeding MR. However, from 49 to 63 days of age, the pH value (p