Calf hormone implants can give environmental, financial wins

Glacier FarmMedia – Hormone implants in suckling calves have had a hard public relations slog with consumers, but cow-calf producers who use them are likely to see greater economic returns while also reducing environmental impacts, a Manitoba study shows.

Deanne Fulawka, a researcher from the University of Manitoba, presented her team’s findings at the Manitoba Sustainable Protein Research Symposium in Winnipeg July 7.

A main point of the study was to get local projections on how implants could impact emissions on Canadian cow-calf operations.

The study modelled scenarios for 130 calves. Under the simulated exercise, calves would have received hormonal implants at30 days old. Results were then compared with 130 simulated unimplanted calves.

Local farm conditions across south-central, southwestern and Parkland regions of the province were plugged into the model. Fulawka’s team estimated greenhouse gas emissions for the three regions using Agriculture Canada’s Holos model.

Ammonia projections were based on simulated manure outputs using Canadian research on beef feed intake, manure practices, body weight and temperature. Regional crop yields, estimated dry matter intake and water needs were taken into account.

The hypothetical revenue producers would get from those cattle was based on prices at local auction marts.

Numbers for birth and weaning weights and average daily gain were based on a 2015 South Dakota State University study, which used Angus and Angus-Limousin cross bull calves. It found that when calves born in March and April received their implants in May, their weaning weight increased by an average of 29 pounds compared to untreated calves. The calves from mature cows gained more than calves from immature cows.

Based on a price of $616 per hundredweight, the Manitoba study estimated that revenue at weaning for its hypothetical calves was $135.80 greater per implanted calf compared to untreated calves.

Total emissions were similar between implanted and non-implanted calves. For example, ammonia emissions for implanted calves were only 0.04 per cent lower.

However, due to the higher weight of implanted calves, the greenhouse gas intensity, measured as kilograms of carbon dioxide equivalent per kilogram of live weight, was 3.72 per cent lower when implants were used.

Implants didn’t change how much land was needed for production of feed (including pasture) or water. Again, however, land use intensity (hectare per kilogram of live weight) and water use (litre per kilogram of live weight) decreased by 3.92 per cent due to higher live weight when calves were marketed.

“There is an economic benefit to the producer, but we also want to send home that message that there is also environmental impact,” she said.

Fulawka noted that South Dakota researchers compared calves implanted at 30 days to calves implanted at weaning, which is when many producers would be implanting their calves. They found that later-implanted calves caught up to those implanted at 30 days and finished at similar weights.

She said Canadian beef producers have set a goal to reduce emissions, adding that every best management practice that is added will get the sector closer to that goal.

The Canadian Cattle Association has set a target to reduce primary production greenhouse gas emission intensity by 33 percent by 2030, according to its website.

It’s estimated that fewer than 30 per cent of producers in the cow-calf sector use implants, which makes this an area of significant opportunity to improve economic and environmental outcomes, Fulawka’s report said.

– Geralyn Wichers is a reporter for Glacier FarmMedia. Her article was published in the July 21, 2025 issue of the Alberta Farmer Express.