Sleep studies and the association of sleep quality with productive, ruminal and metabolic efficiency of beef cattle

Abstract

Like humans, cattle also require a minimum amount of restorative sleep for their metabolic functions to be properly regulated, resulting in improved performance and in a reduced risk of inflammation. The stages of sleep are basically divided into 1) REM (rapid eye movement), 2) non-REM (also known as deep sleep), and 3) light sleep. It is during the REM and non-REM sleep stages that hormone depletion occurs, as well as muscle and neurological recovery. However, little is known about the relationship between sleep quality and beef cattle productivity and welfare, and the few studies available in the literature focused on the sleep physiology of dairy cows. Therefore, we propose in this project an evaluation of a methodology to measure sleep, as well as to develop a noninvasive device that can measure sleep stages in beef cattle. In this regard, five studies will be carried out: 1) The aim is to validate a noninvasive device (accelerometer) that can measure sleep stages in beef cattle, and how it relates to immune function, health, and productivity; 2) The aim of the study will be to evaluate and promote final validation of the use of an accelerometer to measure beef cattle sleep and associate it with ruminal parameters, blood metabolites, and environment in two seasons of the year. Another objective is: based on the results of experiments 1 and 2 to create a classification of sleep quality; 3) The aim will be to evaluate the sleep quality measured in beef cattle and associate it with animal performance, carcass characteristics, feeding behavior, ruminal and cecum morphometrics; 4) The aim is to evaluate the relationship between sleep quality in different breeds of beef cattle, as well as their effects on ruminal and metabolic parameters; and 5) The aim of the study will be to evaluate the relationship between sleep quality and ruminal methane emissions, animal performance, carcass traits, feeding behavior, rumen, and cecum morphometrics of Nellore cattle. Our hypothesis is that cattle presenting improved sleep quality are more efficient in terms of productivity, which can improve animal health and welfare. Identifying the most productive and efficient animals based on sleep quality may generate significant gains in performance and beef production, and reduce environmental impacts. (AU)