Effects of two yeast based direct fed microbials on performance of high producing dairy cows

Abstract

Highlights A yeast culture (XPC) or yeast/microbial culture (YST) were added to a Control (C)  Milk yield was higher with YST, but not XPC, and NE output was higher vs C for both  There were no impacts of either YST or XPC on measures of rumen fermentation  Lower apparent digestion of OM and CP for YST vs C and mainly higher plasma AA  A post-ruminal YST effect improved gut health causing higher absorption efficiency AbstractOur aim was to determine effects of two S. cerevisiae yeast based direct fed microbial (DFM) feed additives on the productive response of high producing early lactation dairy cows. The study consisted of three high producing Holstein cow pens (± 315 cows/pen) in a 3 x 3 Latin square design experiment with 3 periods of 28 d each. The 3 treatments were: 1) Basal total mixed ration (Control), 2) Control supplemented with "XPC" yeast culture at 14 g/cow/d and, 3) Control supplemented with "Yeasture (YST)" DFM at 10 g/cow/d. Milk (P = 0.01), milk true protein (P = 0.01), lactose (P = 0.01) and energy (P = 0.02) outputs were higher for YST cows, and there was a tendency for milk fat (P = 0.07) to increase compared to Control cows. In contrast, milk and component yields were not impacted by feeding XPC.2 Total net energy (NE) output was higher for both DFM treatments versus Control (YST (P < 0.01) and XPC (P = 0.01)), but neither treatment impacted the NE level of the diets. Total tract apparent digestibility of organic matter (OM) and crude protein (CP) tended to be lower (P = 0.08 and 0.05) than Control for the XPC treatment, while total tract apparent digestibility of OM and CP for YST cows was lower (P = 0.02 and < 0.01 respectively) than Control. Total tract apparent digestibility of ash-free neutral detergent fibre (aNDFom) and starch were not affected by treatment, and there was no effect of either DFM treatment on microbial CP (MCP) flow from the rumen. Total plasma essential amino acid (EAA) concentrations tended to be higher (P = 0.07) with YST, which was mainly driven by increases in threonine (P = 0.03), tryptophan (P = 0.02), valine (P = 0.08) and histidine (P = 0.06). Although total plasma non-essential amino acids (NEAA) did not differ with YST feeding, there was an increase in concentrations of glycine (P = 0.04), asparagine (P = 0.03), tyrosine (P = 0.05), serine (P = 0.07), proline (P = 0.06) and taurine (P = 0.07). In contrast, XPC had no impact on plasma concentrations of any AA. Overall, MCP flow and whole tract aNDFom data suggest no substantive impact of either yeast additive on rumen fermentation, but whole tract digestibility of OM and plasma AA concentrations suggest a post-ruminal effect of YST wherein gut health improved thereby leading to increased efficiency of nutrient absorption.

In vitro evaluation of Lactobacillus plantarum as direct-fed microbials in high-producing dairy cows diets

“…Furthermore, studies with less than 30% starch levels in the diets have reported no increase in nutrient digestibility when yeast or lactobacilli were added to the diets since there were no abundant substrates for lactate production ( Doreau and Jouany, 1998 ; Raeth-Knight et al, 2007 ; Hristov et al, 2010 ). Also, Williams and Newbold (1990) and Leicester et al (2016) suggested that supplementation of microbial additives such as yeast may reduce total tract OM digestibility estimation because of an improvement in intestinal health, which could increase the endogenous secretion of OM to the intestine, leading to an underestimation of the true OM digestibility ( Leicester et al, 2016 ).…”

“… Contreras-Goveaa et al (2013) reported that L. plantarum inoculums may improve silage and ruminal fermentation through a reduction in the silage of AA deamination and NH 3 -N concentration, and an increase on ruminal fermentation of microbial N, although ruminal VFA production is not altered. Leicester et al (2016) reported that adding LY or YFP to high-producing dairy cows’ diet reduced total tract protein digestibility which may also be a consequence of reduced feed protein fermentation. In the preliminary Exp.…”

“…Yeast treatments also tended to have different gas pool sizes ( P = 0.06) and YFP was greater than LY treatment as a consequence of the greater OM digestibility. Specifically in in vivo studies, YFP and LY have been shown to have similar effects on apparent total tract OM digestibility ( Doreau and Jouany, 1998 ; Hristov et al, 2010 ; Leicester et al, 2016 ). However, these differences, together with the lack of responses in VFA concentration among yeast additives, may have happened because of an improved fermentation efficiency of LY treatment.…”

“…As an alternative to LY, yeast fermentation product (YFP) containing yeast bioactive compounds and culture media, yet not viable yeast, has recently been used as additives for high-producing dairy cows because it has shown more consistency in its effects. Robinson and Erasmus (2009) , summarized studies with YFP supplementation, and showed increases in milk production; however, some studies did not find positive responses when YFP was fed to high-producing dairy cows ( Hristov et al, 2010 ; Leicester et al, 2016 ).…”

Dietary synbiotics improved the growth, feed utilization and intestinal structure of largemouth bass (Micropterus salmoides) juvenile

“…The similar results were also reported in caspian roach ( Rutilus rutilus ) (Chitsaz, Akrami, & Arab, ), European lobster ( Homarus gammarus ) (Daniels et al, ) and leopard grouper ( Mycteroperca rosacea ) (Reyes‐Becerril et al, ). Leicesterab, Robinsonb, and Erasmus () used a commercial synbiotics (Cenzone Yeasture) containing Bacillus subtilis , yeast, β‐glucan and MOS to feed dairy cow (5 g per cow per day) and observed that the milk production was significantly promoted. However, the effect of this synbiotic has not been reported in aquaculture.…”