Genetics may be part of the equation for beef producers finishing on grass, but forage management may be what really adds up.
Jason Rowntree, former chair of the Grassfed Exchange and faculty co-ordinator at Michigan State University’s Lake City Research Centre, says new grass-fed ranchers should only tie up 20 per cent of investment into genetics.
The remaining 80 per cent should go into improving forage growth, pasture productivity, legume integration and infrastructure for adaptive multi-paddock grazing (also called mob grazing or AMP), one of the founding tenants behind Rowntree’s system and a commonly cited practice for producers tied into regenerative agriculture and soil health.
Why it matters: Producers looking to finish beef on grass are looking for a different set of genetic traits, although experts say most of the investment should go into the feed at first.
“Once I’ve got that moving in the proper direction, then later, maybe five years or further down the road, then I can perhaps start to think more about investing in genetics,” he said. “The point being that I would much rather have average genetics on good grass versus good genetics on poor grass.”
Likewise, a producer may not need to immediately look outside their usual breed. Rowntree does not swear by one single breed, he said, and he has seen anything from Simmental and Charolais to Angus thrive in a grass-fed system.
“It’s not a breed-versus-breed debate,” he said. “It’s identifying those genetics that can work and typically, generally speaking, cattle that shut off faster — meaning that they don’t continue to grow bone and grow muscle, but they grow quickly and then they flatten off and they begin to put on more body condition — those are the types of genetics that we want to see in grazing systems.”
Many breeds can tick those boxes, he said, although British breeds may boast more cows within the breed with those more moderate frames and lower energy maintenance requirements.
Rowntree, himself, looked to replace the Lake City Research Centre’s large-framed herd after joining up with Michigan State University. Today, animals average closer to 1,200 pounds, he said.
Ian Grossart, who finishes his own herd on grass south of Brandon, has noted many of the same things.
“We started trying to bring Devon and some of those genetics in and I found some of the cows that we used to have, that had the Charolais influence or Red Angus, they’ll fit just as well in the program,” he said.
He has, likewise, attempted to draw down animal size through selection.
Small frames, however, may not translate to low feed intake. In one of his trials, Rowntree compared animal performance and forage consumed between five larger-sized and five smaller-framed cattle, with both groups on an irrigated, four-acre paddock. The smaller cattle ate far more than Rowntree expected, based on existing literature. Conventional knowledge would put cattle intake at 1.1 per cent of body weight, he said, while the Michigan State University trial suggested that those smaller-framed cattle were eating closer to two per cent of body weight.
The study found no difference in forage consumed according to size, but smaller cattle averaged 20 kilograms more weight gain. Body condition was likewise higher on the smaller cows by the end of the summer, something Rowntree argued would lower feed requirements for those cattle through winter.
Farm management should also play a part once producers start thinking seriously about genetics, Rowntree said.
“If I’m then thinking about genetics, I’m really looking at how the seedstock herd are being managed and are the cattle being managed in a way that replicates what I want to do? Or are they potentially in a very cushioned environment where there’s a lot of supplementation?” he said.
That selection may take place within the herd over time as producers select bulls and tailor their females, culling any that do not take as well to the system and prizing those that trend towards higher intake of lower-quality ruffage.
Brian Harper, whose own adaptively managed pastures near Brandon have earned him accolades, including last year’s national TESA award for environmental stewardship, says he singles out animals with a large, hard girth, “with room for lots of forage.”
His herd is selected for adaptability, high forage intake and hardiness in the face of disease and environment pressures, he said.
“For us it’s just the hard girth and matching the hard girth with the body length,” he said.
Grazing to finish
Cows may have never seen grain if slated for the grass-fed market, but grass fed does not always mean grass finished.
Many of the downfalls of grass-fed beef may be due to improper finishing, Rowntree argued, and things like off-flavour meat may be due to insufficient fat insulation when the carcass is cooled. His own finishing system hopes to see three-tenths of an inch of back fat at the last rib on a finished carcass.
Rowntree also urged producers to be more deliberate with rotational grazing. His own system started by moving cattle arbitrarily three times a day, but quickly found that schedule overgrazed legumes while overresting grasses. True AMP grazing should be deliberate, he argued, with a certain stock density chosen for a certain paddock at a certain time and for a certain length of time to achieve a certain goal on the landscape.
Farmers may need to push the recommended rest period when finishing, he said. While he normally gives paddocks 45-60 days between grazing — a number that researchers in Manitoba have put closer to 75 for finishing, he returns when plants are more vegetative and higher in feed value. Those same paddocks, however, are then first in line for a long rest to avoid mining fertility and overgrazing.
Rowntree’s system takes 18- to 20- months to finish a calf, although he says farmers in Manitoba may find a longer window more forgiving.
Grossart has courted that 18-20 month period, with similar 600-pound carcasses, although he has also pushed the window back to two years.