Rumen bacterial composition in lambs is affected by β-adrenergic agonist supplementation and heat stress at the phylum level1

Effect of environmental temperature and β-adrenergic agonist supplementation on rumen volatile fatty acid production in sheep

“…The observed change in total VFA is contrary to Walker and Drouillard (2010) in which RH added directly to buffered ruminal fluid had no impact on VFA levels, showing that RH does not affect microbial growth or fermentation end products when grown in pure cultures. RH supplementation did not change bacterial composition in these sheep ( Duffy et al, 2018 ); however, RH and the interaction of RH with environment impacted production of VFAs. This implicates another mechanism, besides the change in the bacterial community itself in altered VFA production.…”

“…In addition, temperature and humidity have a notable effect on the rumen microbial composition which may lead to changes in VFA production ( Tajima et al, 2007 ). A significantly different microbial composition was present in these lambs comparing HS to TN conditions ( Duffy et al, 2018 ), therefore we expected to see a clear difference in VFA as well. However, these results suggest that the response due to the interaction between environment and supplementation is more complex.…”

“…With the profound role of VFA production in energy status of the ruminant, and given that heat stress (HS) events can affect ruminal microbial populations ( Tajima et al, 2007 ; Duffy et al, 2018 ) HS thereby may alter energy substrate available to the animal. Significant reductions in VFA levels have been reported during increased environmental temperature in both ad libitum and limit-fed animals ( Weldy et al, 1964 ; Kelley et al, 1967 ; Freestone and Lyte, 2010 ).…”

“…The objective of this study was to determine the impact of β1 agonists, β2 agonists, and HS on rumen VFA production using lambs as a model for cattle. Our prior work showed that heat stress, but not β-AA alone, changed the overall composition of the ruminant microbiome ( Duffy et al, 2018 ). These changes in the microbiome are postulated to change VFA production.…”

Individual differences in behaviour and gut bacteria are associated in collared peccary (Mammalia, Tayassuidae)

“…Given that both stress (e.g. Duffy et al 2018) and different levels of dietary fibre (e.g. Petri et al 2013;Henderson et al 2015) affect the gut microbial-community diversity and its products, we predicted that the diversity of the bacterial community in the forestomach contents of collared peccary would be linked with both the individuals' coping style and dietary fibre level.…”