Fewer antibiotics needed to fatten calves, study shows

Researchers found that calves kept separately in the open air and vaccinated against pneumonia caught fewer respiratory and digestive tract diseases and had a lower death rate than animals on standard farms. Keystone / Laurent Gillieron

Swiss researchers have developed a unique method to reduce the use of antibiotics in calves while still maintaining the profitability of farms.

Farmers in Switzerland rely heavily on antibiotics in the process of fattening calves, even though efforts have been made in recent years to reduce their use. The drugs are commonly administered to treat pneumonia in the animals, an illness to which they are especially prone in the first weeks of life, said project leader Mireille Meylan of the veterinary school at the University of Bern.

The illness can spread quickly because calves are often transported to the fattening farm together with other animals and then join bigger groups of animals upon arrival.

In the approach developed by the researchers, farmers bought calves from nearby farms and transported them directly to avoid contact with other animals. In the first weeks, the calves were kept in individual pens in the open air and were vaccinated against pneumonia. This method was tested on 19 farms over a period of 12 months and their experiences were compared to 19 control farms that adhere to the IP-SUISSE labelExternal link, which signifies that farmers treat their animals according to defined standards of care.

The researchers, whose project was funded in part by the Swiss National Science Foundation, found that the “free-range calves” caught fewer respiratory and digestive tract diseases and had a lower death rate than animals on the control farms.

“This is remarkable, not least because the comparison farms also achieved quite exemplary results in terms of animal health,” said veterinary researcher Jens Becker. Only one in six of the free-range animals needed antibiotics in its lifetime, compared to every second calf on the control farms.

The team also calculated the costs for farmers to keep calves using this method and concluded they were similar to costs for an IP-SUISSE farm.

Meylan said that moving to a large-scale application of the method would require recognition from labels, federal agencies and large distributors but added that ultimately, the approach was viable both economically and as a way to fight antibiotic resistance.