July 29, 2015 Comments are off Montana Stockgrowers Association
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Monitor Bulls for Activity and Injuries During Breeding Season

cobb charolais bullThe majority of beef herds in this region are in the heart of their breeding seasons, and many of those that aren’t will start their breeding seasons soon.

“From a management standpoint, the work isn’t over once breeding soundness exams are conducted and potentially fertile bulls are turned out to breeding pastures,” says Carl Dahlen, North Dakota State University Extension Service beef cattle specialist.

To ensure a successful breeding season, bulls should be monitored carefully for breeding activity, injuries and overall condition throughout their time in breeding pastures, he advises. The desire of a bull to breed, or libido, is not something that can be determined during a breeding soundness exam. In addition, breeding is a learned behavior, so producers should pay particular attention to monitoring yearling bulls.

“To monitor breeding activity, simply take the time to watch pastures and make sure bulls are actively seeking and breeding females,” Dahlen says. “While watching bulls, physical deformities (deviated penis, inability to extend penis, etc.) and other issues that can prevent successful intromission and ejaculation from occurring also can be identified. In these instances, a bull may be mounting cows in heat but not completing a successful breeding. Pay attention to the entire mating process to make sure erection, intromission and ejaculation all are occurring.”

Injuries are another major issue that can be identified while monitoring bulls. Some injuries can severely limit or eliminate a bull’s ability or desire to breed females successfully. A summary of breeding soundness exam results from North Dakota veterinarians revealed that injuries to reproductive organs were a major reason for mature bulls failing tests.

“As these injuries were identified during a breeding soundness exam and not during the breeding season, close observation is required,” Dahlen says.

Major injuries that would make bulls physically unable to perform, such as broken or sprained legs, likely would be easy to spot. Lacerations that result in a penis not being able to retract are easy to see as well. Other cases are not as easy to identify. For example, swelling just ahead of the scrotum may indicate a “broken penis” or a hematoma, and swollen or misshapen testicles may indicate testicular injuries.

Injuries may cause physical pain and a low libido, or a bull may be willing to breed but is no longer capable. In any case, part of the healing process can create scar tissue, and this scar tissue may interfere with future reproduction.

Dahlen recommends observing bulls interacting with females and females interacting with each other early in the breeding season because those interactions can give a good indication of the relative proportion of females that are cyclic.

If all cows are cyclic, producers should expect to see almost 5 percent in estrus on a daily basis. Fewer and fewer females will be in estrus on a daily basis from the middle to the end of the breeding season.

So if 65 percent of the cows became pregnant in the first 21 days, then only 35 percent of the herd remains to be bred. This means less than 2 percent of cows would be in estrus per day from day 22 to 42 of the breeding season. After day 42 of the breeding season, less than 1 percent of females should be in estrus every other day for the remainder of the breeding season.

Ideally, cows should be on an increasing plane of nutrition with sufficient supplies of mineral and high-quality pastures or feeds during the breeding season. If close observation of pastures reveals that a relatively similar proportion of cows are in estrus in the middle of the breeding season, compared with early in the breeding season, then some type of intervention is critical.

Once bulls have been evaluated for injuries, body condition and libido, and single-sire pasture bulls have been evaluated for the ability to mate successfully, producers should take active steps to rotate or replace bulls that are injured, have low libido or are in pastures with a high proportion of estrus cows late in the breeding season.

“Identifying potential issues before the end of the breeding season can allow a producer to take active steps to salvage the remainder of the breeding season and ensure a greater proportion of the herd becomes pregnant,” Dahlen says.

For more information, contact Dahlen at (701) 231-5588 or [email protected], or NDSU Extension veterinarian and livestock stewardship specialist Gerald Stokka at (701) 231-5082 or [email protected].

May 25, 2015 Comments are off Montana Stockgrowers Association
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Livestock Producers Need Stocking Rate Reduction Plan

moving cattle montana pastureLivestock producers should have a drought management plan in place prior to pasture turnout in case drought persists into the growing season this year, North Dakota State University Extension Service livestock and rangeland specialists say.

Producers need to have a good idea how to assess available forage, feed and water supplies to determine if they need to reduce their stocking rates or modify grazing plans before they turn their cattle out onto pasture this spring, according to beef cattle specialist Carl Dahlen. The stocking rate is the number of specific kinds of animals grazing a unit of land for a specified time.

Developing a plan early is important because 80 percent of the grass growth on rangeland is dictated by May and June precipitation. Drought conditions during that time will reduce the amount of grass available on pasture and rangeland for the duration of the grazing season, rangeland management specialist Kevin Sedivec says.

If producers don’t reduce the stocking rate to compensate for the loss of grass, overgrazing can result. Overgrazing affects the entire rangeland plant community, leading to a loss of plant species diversity and biomass, soil erosion, weed growth and a reduction in the soil’s ability to hold water, livestock environmental stewardship specialist Miranda Meehan explains. Drought conditions also can lead to increased risk of toxicity from selenium and nitrates in plants.

“It takes a lot longer for the entire ecosystem (plants, soils, water, etc.) to recover if you don’t prepare and take active steps to change management in response to drought,” she says.

She advises producers to use the National Drought Mitigation Center’s U.S. Drought Monitor to keep track of the conditions.

“Selective culling is a quick way to reduce the stocking rate,” Sedivec says.

It also could be profitable because cattle prices are high.

“It’s a seller’s market right now,” he notes.

Culling targets include cows that are old, have a poor disposition or physical structure, or had a difficult time giving birth this spring and have a low chance of rebreeding.

“The importance of records is magnified in times when tough culling decisions need to be made,” Dahlen says. “Good calving and production records can help producers pinpoint cows that could be culled.”

Locating sources of and feeding alternative feeds is another way to reduce the risk of overgrazing.

In cases when surplus wet distillers grains, a byproduct of ethanol production, are available as a result of dryer shutdown or reduced railcar availability, producers may have the opportunity to purchase those grains in early to midsummer at a relatively low cost, Dahlen says. The drawback is that the distillers grains are a wet product, but producers can use storage methods to preserve the nutrient quality until the feed is needed.

Producers also should evaluate hay and stockpiled forage remaining from last year that could be used to delay pasture turnout this year or supplement pasture grass later in the grazing season, Meehan says.

Other options the specialists suggest producers consider if warranted include weaning calves early, providing cattle with creep feed or feed supplements, and feeding cattle in drylots. Weaning early eliminates the cows’ energy demand for milk production, which may result in reduced intake of pasture grasses and improvements in body condition once the calves are removed, Dahlen says.

For more information on dealing with drought, contact the local county Extension office or visit NDSU Extension’s “Ranchers Guide to Grassland Management IV.”

–NDSU Extension Service