TITLE:
A Study on the Mechanism Regulating Acetate to Propionate Ratio in Rumen Fermentation by Dietary Carbohydrate Type
AUTHORS:
Xueyan Lin, Zhiyong Hu, Shizhe Zhang, Guanwen Cheng, Qiuling Hou, Yun Wang, Zhengui Yan, Kerong Shi, Zhonghua Wang
KEYWORDS:
Rumen Acetic Acid Propionate Ratio, Calcium Pyruvate, Rumen Microbiome, Volatile Fatty Acid
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.11 No.8,
August
6,
2020
ABSTRACT: The research direction of our team is nutrition and physiology
of ruminants, including dietary nutrition metabolism and rumen microorganisms.
Previous research has shown that ruminal acetate-to-propionate ratio is related
to diet utilization efficiency. At present, it is believed that the main
factors affecting the ruminal acetate-to-propionate ratio are the degradation
rate of the diet and the rumen microbial structure, but the main mechanism is
unclear. This
study found that the effect of ruminal
acetate-to-propionate ratio was not affected by the concentration of the
fermentation substrate, but was affected by the structure of the rumen
microbiota. We believe that changes in the rumen microflora structure are the
main mechanism for regulating the ruminal acetate-to-propionate ratio. This
will help people to further understand the rumen physiology, thereby gradually
improving feed conversion efficiency and reducing production costs. Abstract: In order to explore the mechanism by which diet regulates the
acetate-to-propionate molar ratio (A: P ratio), we compared the effect on rumen
fermentation parameters and the microbiome by altering the ratio of dietary
concentrates to roughage ratio and calcium pyruvate infusion. The test animals
were Laoshan dairy goats, and were fed continuously through an automatic feeder.
The test groups were fed a base diet of low concentrates, and intraruminally
infused with calcium pyruvate at two concentrations. The infusion
concentrations were derived from the difference in the rate of carbohydrate
degradation of the high and low concentrate diets, and they were artificially
set such that the high concentration infusion group was infused with twice the
concentration as the low concentration infusion group. The control groups were
fed high concentrate (6:4)
and low concentrate (3:7) diets, respectively. The following results were
obtained by measuring rumen fermentation parameters and microbial composition:
the rumen A: P ratio was significantly lower in the high-concentrate diet group than in the low
concentrate diet group (P 0.05), while
infusion of high concentration calcium pyruvate significantly increased the
rumen A: P ratio (P effect on rumen microbial structure. The above
results indicate that increasing the concentration of the fermentation
substrate without affecting the composition of the microflora does not reduce
the A: P ratio. Microbiological results showed that the A: P ratio was more
closely related to the rumen microflora structure. Therefore, it is believed
that rumen microflora structure is the main mechanism regulating A: P ratio in
rumen fermentation.