Credit: Journal of Animal Science, Volume 98, Issue 6, June 2020, skaa194, doi.org/10.1093/jas/skaa194
Publisher: American Society of Animal Science
Rights: Name must appear as a credit whenever the image is used- Journal of Animal Science, Volume 98, Issue 6, June 2020, skaa194, https://doi.org/10.1093/jas/skaa194
Description: Heat stress represents one of the more harmful effects experienced by livestock. The environmental insult causes a reduction in feed intake that only partially explains the deficits to performance outcomes (Belhadj Slimen et al., 2016). Short periods of heat stress lead to an increase in inflammatory cytokines as well as impaired insulin signaling in the muscle which may underlie poor growth responses (Ganesan et al., 2017; Ganesan et al., 2018). To offset heat stress, cattle fed an immunomodulatory supplement exhibited reduced core body temperatures during periods of elevated environmental temperatures which may contribute to welfare improvements (Colombo et al., 2019; Crook et al., 2020). In this issue, Swanson et al. (Swanson et al., 2020) report that ractopamine can improve muscle growth in lambs without further exacerbating the negative consequences of heat stress. These results, and others, bolster ongoing efforts aimed at improving our understanding of the physiological importance of heat stress and heat stress abatement.