Antibiotic Use In Beef Herds

By Dr. John Comerford

A recently completed survey of beef owners in Pennsylvania provided some insight into the use of antibiotics in commercial beef cattle operations in the mid-Atlantic. The project was funded by the Pennsylvania Department of Agriculture and was conducted by the Beef Extension Team at Penn State. Additional information included the types of cattle that were marketed and the demographics for the beef industry in the state.

Animal health

The primary purpose of the survey was to determine the health practices used on beef farms relative to vaccines and antibiotics. Just over half of the farms (56.4 percent) use vaccines on the farm, with a similar percentage that routinely administer boosters. Diseases most targeted with vaccines were the bovine respiratory complex, scours and pinkeye. More than 40 percent of farms replied that there were no major health problems on the farm. This would be typical of smaller, closed herds. Over 28 percent of farms never use a vaccine on the farm, which generally indicates there were no health problems identified that required control measures. Coupling those using no vaccines with nearly 60 percent that do, it's not surprising that a high percentage of the farms did not experience health problems. One of the more surprising results indicated 87.3 percent of farms had functioning animal handling facilities available, and significantly fewer of these farms appeared to use them for routine vaccination programs. The primary health issues that were identified from those farms that indicated any health issues were bovine respiratory disease (12 percent) and pinkeye (12 percent). Neonatal calf losses and internal and external parasites were reported in less than 5 percent of farms. Proper vaccination of calves can significantly prevent respiratory disease, while pinkeye and calf losses are generally based in management.

Antibiotic use on beef farms is very minimal. Less than 5 percent of all animals on 80.6 percent of farms received any antibiotics; over 90 percent of farms treated less than 10 percent of their cattle; and only one farm treated more than 50 percent of their cattle. Subtherapeutic antibiotic use is generally considered the most controversial use of antibiotics in food animals, and it was limited to about 16 percent of all farms using antibiotics (3 percent of all beef farms surveyed). Sixty-eight percent of the four to five farms using subtherapeutic levels used these treatments less than 10 days, with only one farm surveyed using antibiotics at this level for more than 30 days.

The summary of antibiotic use from the farms surveyed was that over 80 percent of farms used few or no antibiotics; when antibiotics were used, it was to treat sick animals; and subtherapeutic use was very limited and in place for very short periods of time.

Veterinary services were limited on most beef farms. Nearly 75 percent of farms had less than three visits from a veterinarian annually, but 10 farms indicated the veterinarian visited the farm more than seven times per year. Nearly half of all visits were for the treatment of sick animals, and about one-third were for preventive health practices. Less than 15 percent of all veterinarian visits were related to consultation and management issues.


The farms that were surveyed are representative of the typical beef farm, particularly in the Northeast. The respondents were well-sampled across the regions of the state, with 40 of 63 counties represented in the results. Typical of the region, average farm size was 187 acres and nearly half of all farms marketed 11 to 40 cattle. The primary products are feeder calves and purebred cattle. Finished beef sales will usually be regional in Pennsylvania because of the concentration of feedlots in the southeastern part of the state. There is a diversity of markets that are used because of the smaller farm sizes, with nearly one-fourth of all sales as freezer beef. Nearly all other markets are to other farmers, either directly or through auction barns. It is anticipated the purebred breeder component (16.5 percent) contributes heavily to direct sales to other farmers.

The typical Pennsylvania beef farmer is 55 to 65 years of age and uses the farm as supplemental family income. Most (78.9 percent) are the sole owner of the farm. Since the beef enterprise is not a full-time enterprise nor a major source of income to most of these farmers, innovation and adoption of new technology will be slower. Adoption will probably be narrowed to those activities that do not significantly disrupt the current conditions on the farm, yet practices will be adopted where there will be a perception of improved profitability. About 50 farms surveyed were not certified through the Beef Quality Assurance (BQA) program to learn best management practices on the farm relative to food safety and product wholesomeness. This result indicated that a significant pool of students remains for BQA training in Pennsylvania and possibly throughout the Northeast.


The results of the survey provide a snapshot of the industry. Since more than 55 percent of cattle are marketed through auction barns or sold directly to other producers, there is little use of value-added markets, except for the nearly one-fourth of farms that sell freezer beef. The lack of vaccine use will invite a "health wreck" on many farms. Vaccine use is fairly low, with just over half of the farms using them. Vaccines provide the best and cheapest resistance to disease, and disease can enter a herd in myriad ways - not just from outside cattle. Particularly troubling is that, for farms that use vaccination, nearly one-third do not use a booster vaccine, which renders the initial vaccine nearly worthless. As marketing programs and consumer preferences continue to change, new management activities will be needed to meet these changes.

Dr. John Comerford is an associate professor of dairy and animal science at Pennsylvania State University.