Until now, two types of β-adrenergic agonists (βAA) have been regulated in cattle raised for human consumption. Since their first approval in 1999 by the United States Food and Drug Administration (FDA), the βAA agonists have been in-feed administrated to enhance lean muscle gain, increase growth rate, and increase feed efficiency. Additional uses for β-adrenergic agonists are in medical clinics for diverse acute interventions for asthma and chronic obstructive pulmonary disease (COPD) patients.
In clinical medicine, secondary unintended effects have been observed, including an increased risk of asthma exacerbations and hospitalizations, arrhythmias and myocardial infarction and death. Furthermore, even when being administered according to label directions, resulting in well-characterized and predictable improvements in weight gain, leanness and yield of edible beef products, there have been diverse anecdotal reports that associate the use of βAA with an increase of cattle mortality rate.
Concerned by the use of βAA, Dr. Guy H. Loneragan, from Texas Tech University and his colleagues, Dr. Daniel Thomson and Dr. Morgan Scott from Kansas State University, aimed to quantify the association between administration and mortality in feedlot cattle. The study consisted in the scrupulous analysis of three confidential datasets.
“Through our extensive analysis, we found that the incidence of death among cattle administered beta agonists was 75 to 90 percent greater than cattle not administered the beta agonists,” Loneragan said. “This increase in death loss raises critical animal-welfare questions. We believe an inclusive dialogue is needed to explore the use of animal drugs solely to improve performance, yet have no offsetting health benefits for the animals to which they are administered. This is particularly needed for those drugs that appear to adversely impact animal welfare, such as beta agonists.”
On February 18th, a mini symposium regarding the use of βAA was held at Texas Tech University, the key speaker, Dr. Temple Gradin, professor at Colorado State University said, “These problems have got to stop. I’ve laid awake at night about it. I’ve worked all my career to improve how animals are handled and these animals are just suffering. It has to stop.”
To conclude the symposium, Dr. Loneragan added “To paraphrase Dr. Grandin, we owe the animals we raise for food a decent life and a decent death. We certainly need to better understand the manner in which animals fed beta agonist die at the feedlot and work out how to balance the societal benefits of beta agonist use with societal expectations concerning the welfare of animals raised for food.”