Males More Stressed by Travel
Young male cattle have increased risk of respiratory disease during transport.
According to a study by researchers at Kansas State University (K-State), excessive travel can have detrimental effects on the respiratory health and overall performance of cattle. In a paper published online ahead of print by the Journal of Animal Science, the researchers reported that male cattle, postweaning cattle and cattle traveling during the summer showed increased risk for contracting bovine respiratory disease (BRD) complex. BRD can be fatal to cattle, and cattle that survive can have long-term lung problems.
The researchers measured the distance that cattle in different feedlots traveled across the United States and compared that distance with rates of BRD. They also looked at health indicators such as body weight they gained after travel and the weight of the unchilled carcass after slaughter.
Lighter-weight cattle were found to be at greater risk of BRD than heavier cattle, which White said may be because they were younger at time of transport. The risk of BRD is greatest in the early postweaning phase. Male cattle also showed an increased risk, though the reason for this is difficult to determine because this study did not distinguish between castrated and non-castrated males.
The study showed that cattle morbidity during transport peaks in the summer and early fall. According to White, this seasonal difference could be due to high temperatures and humidity in summer and the transport of less robust postweaning cattle in the fall.
“I think it is important to consider if strategies could be implemented prior to transit to mitigate the disease risk associated with these groups,” White said.
This study was observational, so White did not draw conclusions about the cause of the correlation between travel and BRD. However, he and his fellow researchers noted in the paper that the strength of the study is its wide representation of different groups of cattle. Across all groups studied, the same trends persisted; body weight, sex of the calf and time of the year were important factors in increased risk of BRD during transport.
The study was titled “Effects of body weight loss during transit from sale barns to commercial feedlots on health and performance in feeder cattle cohorts arriving to feedlots from 2000 to 2008.” It can be read in full at http://bit.ly/162db9q.
Editor’s Note: This article was provided by the American Society of Animal Science.