Beef: Pasture calving wins out over barn calving, study shows

Tuesday, June 3, 2008

A five-year research project shows that margins were higher, calves healthier and labour requirements less for pasture calving than for its barn equivalent. But a changeover will delay cash flow in the first year

by Susan Mann

Ten years ago, after a nasty outbreak of scours among his new born calves, cow-calf farmer Amos Brielmann decided to change his calving methods.

Brielmann recalls his snowsuit pockets being full of antibiotic bottles and needles as he and three full-time employees worked night and day to treat the calves at Pine River Ranch, near Rainy River in northwestern Ontario. At that time, his 300-cow herd was calving in late March, early April. 

"I decided we couldn't do this," he says. "It was way too hard on everyone."

Brielmann became intrigued by the idea that the natural calving time of cows is in June, near the longest day of the year. He visited ranches in Alberta to see cows calving on pasture. Brielmann came back convinced this was the way for him to go.

Just how does barn calving stack up to pasture calving? The Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) and University of Guelph researchers studied that question for five years at the university's New Liskeard Research Station. They compared animal performance, cost of production and labour efficiency.

The station's existing herd was split into two comparable sub-herds with similar genetics and age structure. Each year, the same sires were used in both groups. One group was bred to calve mid-February to mid-April in special indoor, unheated pens, while the other group was bred to calve in June or July on pasture. Winter housing for both groups was a naturally ventilated barn.

The study found that pasture-born calves weren't as likely to need help being born. Barn heifers had an assistance rate that was more than three times greater than their counterparts on pasture, while barn cows had an assistance rate five times greater than pasture cows.

That may be because summer-born calves were on average six pounds lighter than winter born ones. Another factor may be that the calving pens' location made it more likely for barn cows to be observed giving birth.

Pasture cows were checked at least twice daily. Initially, researchers were concerned that they would have problems with neonatal calf survival because workers weren't able to see every calving. "In fact, they saw very few calvings," says Tom Hamilton, OMAFRA's beef program lead for production systems, adding that cows preferred giving birth either in the late evening or early morning. Brielmann says that on his farm he doesn't see many calves being born.

The barn group of calves also had a much higher intervention rate for health reasons, such as hand-feeding colostrum and treatment with anti-diarrhea products. Those interventions resulted in both labour and product costs. In addition, about 30 per cent more bedding was needed annually for the barn calving group compared to the pasture group.

Researchers also treated fewer calves from the pasture group for illness.

"It was a healthier environment for them," Hamilton notes, adding that there isn't the same buildup of bacterial and viral diseases from manure as there can be inside a barn.
Calf survival was the same for mature cows in both groups, but the pasture group heifers had a significantly higher weaning rate – 92 per cent compared to the barn heifers' 80 per cent.

The cost of raising cattle was higher for the barn group compared to the pasture group. It took about $47 more per cow for the barn calving system compared to the pasture one. The net margin for the pasture group was $113 per cow exposed to breeding – 45 per cent higher than the $78 per cow for the barn group.

Researchers concluded that, for a given amount of labour, 25 per cent more cows could be kept with a pasture calving system compared with barn calving.

Physically it's not hard or expensive to switch to pasture from barn calving, Hamilton says. Just some fencing may be required to create calving paddocks.

What will be different is marketing. Switching calving dates delays cash flow in the first year. "After that, farmers need a plan for marketing those animals effectively," Hamilton says. "They're not going to be ready for the traditional fall sale of weaned calves in October. Those calves won't be ready to be sold until Christmas time." BF