Effect of sequestering agents based on a Saccharomyces cerevisiae fermentation product and clay on the ruminal bacterial community of lactating dairy cows challenged with dietary aflatoxin B1

Abstract

This study was conducted to examine the effects of clay (CL) and Saccharomyces cerevisiae fermentation product (SCFP) on the ruminal bacterial community of Holstein dairy cows challenged with aflatoxin B 1 (AFB 1 ). A second objective was to examine correlations between bacterial abundance and performance measures. Eight lactating dairy cows stratified by milk yield and parity were randomly assigned to 4 treatments in a 4 × 4 Latin square design with 2 replicate squares, four 33-d periods, and a 5-d washout between periods. The treatments included (1) control (basal diet, no additive); (2) T (control + 63.4 µg/kg AFB 1 , oral dose); (3) CL (T + 200 g/head per day of sodium bentonite clay, top-dress); and (4) CL+SCFP [CL + 19 g/head per day Diamond V NutriTek (Diamond V Inc., Cedar Rapids, IA) + 16 g/head per day MetaShield (Diamond V Inc.), top-dress]. Cows were adapted to diets containing no AFB 1 from d 1 to 25 (predosing period). From d 26 to 30 (dosing period), AFB 1 was orally dosed and then withdrawn for d 31 to 33 (withdrawal period). During the predosing period, compared with the control, feeding CL and CL+SCFP increased the relative abundance of the most dominant phylum, Bacteroidetes (55.1 and 55.8 vs. 50.6%, respectively), and feeding CL+SCFP increased Prevotella abundance (43.3 and 43.6 vs. 40.0%, respectively). During the dosing period, feeding AFB 1 did not affect the ruminal bacterial community, but the relative abundance of Fibrobacteraceae increased with CL+SCFP compared with T (1.45 vs. 0.97%); Fibrobacter abundance also tended to increase with CL+SCFP compared with T and control, respectively (1.45 vs. 0.97 and 1.05%, respectively). Feeding AFB 1 with or without CL or CL+SCFP did not affect ruminal pH or concentrations of NH 3 -N, total volatile fatty acids, or individual volatile fatty acids. Milk yield and milk component yields were positively correlated with the relative abundance of unclassified Succinivibrionaceae, unclassified YS2, or Coprococcus. Feed efficiency was positively correlated (r ≥ 0.30) with the relative abundance of unclassified YS2, Coprococcus, or Treponema. Feeding aflatoxin at 63 µg/kg, a common contamination level on farms, did not affect the abundance of dominant bacteria or rumen fermentation. When aflatoxin was fed, CL+SCFP increased the abundance of Fibrobacter, a major fibrolytic bacteria genus. Milk yield and DMI were positively correlated with abundance of Succinivibrionaceae and Coprococcus. Feed efficiency was positively correlated with abundance of Coprococcus, Treponema, and YS2. Future studies should speciate culture and determine the functions of the bacteria to elucidate their roles in the rumen and potential contribution to increasing the performance of dairy cows.

Characterization of rumen microbiome and immune genes expression of crossbred beef steers with divergent residual feed intake phenotypes

“…Muribaculaceae is a family of bacteria that produces enzymes capable of degrading complex carbohydrates and has been reported to produce short-chain fatty acids(Barouei et al, 2017;Obanda et al, 2018), which play important roles in regulating immune function and energy metabolism. A recent study revealed that the abundance of Muribaculaceae in the rumen is positively correlated with feed e ciency and other production traits such as milk components(Jiang et al, 2020) and negatively correlated with methane production in Holstein dairy cows(Cunha et al 2017).As seen in our result, the relative abundance of Moryella was greater and that Clostridium_sensu_stricto_1 was lower in low-RFI compared to high-RFI. Previous studies have shown that species of Moryella play a key role in the breakdown of complex carbohydrates and the production of volatile fatty acids (VFAs) such as acetate, propionate, and butyrate, which are important energy sources that support improved health and performance of ruminants(Carlier et al, 2007;Hu et al, 2020).A study correlating individual RFI values with bacterial abundances in feces reported that Clostridium I is associated with high RFI in chickens(Siegerstetter et al, 2018;Liu et al, 2021).…”

Alterations in rumen microbiota via oral fiber administration during early life in dairy cows

“…Tong et al 35 reported that Ruminococcus 2 and Muribaculaceae are relatively more abundant in dairy cows with higher milk yields. Another study reported that the abundance of Treponema and Muribaculaceae in the rumen is positively correlated with milk yield, milk fat content, milk protein content, and feed efficiency in dairy cows 36 . Furthermore, Cunha et al 37 suggested that the presence of Schwartzia , Treponema, and Muribaculaceae is negatively correlated with methane production in Holstein cows.…”

Characterization of rumen microbiome and immune genes expression of crossbred beef steers with divergent residual feed intake phenotypes

“…Muribaculaceae is a family of bacteria that produces enzymes capable of degrading complex carbohydrates and has been reported to produce short-chain fatty acids [ 38 , 39 ], which play important roles in regulating immune function and energy metabolism. A recent study revealed that the abundance of Muribaculaceae in the rumen is positively correlated with feed efficiency and other production traits such as milk components [ 40 ] and negatively correlated with methane production in Holstein dairy cows [ 41 ].…”