Meeting the Cow’s NUTRITIONAL NEEDS
Successful breeding depends on a targeted nutritional program. Producers must know the stress periods when a cow can experience nutritional deficiencies, as well as how to supplement available forage during those times.
By Terri Queck-Matzie
That was the message from Travis Mulliniks, Range Cow Nutritionist at the University of Nebraska West Central Research and Extension Center in North Platte, Nebraska.
He presented material outlining a cow’s nutritional requirements through the reproduction cycle at the 3-State Beef Conference held earlier this year in Greenfield, Iowa, Savannah, Missouri, and Syracuse, Nebraska. The conference is an annual event sponsored by Iowa, Missouri and Nebraska Extension.
Mulliniks says producers must know the stress periods when a cow can experience nutritional deficiencies, as well as how to supplement available forage during those peak times.
“Late gestation, generally 90 days before calving, and early lactation, 50-100 days after calving, are the times to pay the most attention to the cow’s nutritional needs,” says Mulliniks.
While some are reticent about over supplementing in the third trimester for fear the calf will be too large at birth, Mulliniks emphasizes the need to maintain a Body Condition Score (BCS) of 4 to 6. “A cow’s body condition score is a crucial element in her breeding and raising a calf successfully,” says Mulliniks.
A cow needs to be able to channel nutrients to the calf during this period of heavy calf growth without damaging her own condition.
Gestational nutrition can affect placental efficiency, fetal organ development, calf weaning weight, age at puberty and carcass quality. Calves may also experience passive immunity, with a greater risk of morbidity and respiratory infections. Calves born to cows who were thin at calving are shown to have ongoing immunity issues, with increased sickness and death in the feedlot.
Added to the challenge of keeping late-term spring calving cows well fed, in many parts of the country, is cold stress. Cattle energy needs to increase about 1% for each degree below 32 degrees in dry cold, in wet weather its 2% for each degree below 59 degrees. Kansas State University research shows a 1,200-pound cow subjected to 20 F in a 14 mph wind requires about 28% more energy than at 32 F with no wind.
“If you’re not providing what they need, cows can lose BCS quickly. A cow can drop .5 BCS (~35 lbs.) in about 2 weeks in a wet, cold snap,” says Mulliniks. “It’s important to intervene quickly in that environment.”
Mulliniks recommends sending forage/hay samples off to be analyzed for quality. Understanding the quality of feedstuff can help you save money and meet the nutrient requirements of your cows. Keep in mind, dry matter intake decreases as calving nears.
Get Ready For Breeding
A cow in poor condition is also less likely to rebreed on schedule, making the period following calving the second crucial segment of the breeding cycle. Cows in early lactation have the greatest protein and energy requirements of the production cycle.
The lactating cow needs ample high quality forage/roughage, preferably immature high quality grass or corn silage. Additional protein or energy may be needed in the form of a fiber-based energy supplement such as Dry Distiller Grains (DDGs) or wheat midds plus a protein supplement. Mulliniks says use caution with starch-based energy due to its impact on increasing milk production and potentially decreasing energy intake.
Protein supplements of more than 20% Crude Protein (CP) can be fed 1, 3 or 7 times per week without changing performance. Energy supplements need to be fed daily or at least every other day with a fiber-based energy source.
“It’s crucial to get them gaining as soon as possible,” says Mulliniks. “That’s more important in young cows than older ones who have been through it a few times.” And it isn’t easy. The cow will channel nutrients into her milk before reproduction. Mulliniks adds selecting breeding stock for high milk production may add to the problem, putting pressure on the cow’s ability to recover and rebreed.
If a cow is not recovering fast enough, the calf may need to be weaned early to allow the cow to improve her body condition before winter. Mulliniks says some producers find it helpful to sort thin and young cows from older cows to make early weaning easier and to reduce young cows competing for feed with older ones.
While her nutritional needs decrease once the calf is weaned, the cow still has some time to improve BCS. Mulliniks says a cow that is thin at weaning (BCS <5) needs protein and energy. If her BCS is >5, she needs protein. Both need a chance to consume abundant immature grass 3 to 5 weeks ahead of breeding season.
Not only does BCS affect the cow’s success in breeding back, but whether she is gaining or losing BCS matters. Research shows cows gaining BCS have a higher rate of conception and those losing BCS have a lower rate – no matter the starting point.
“Body condition score plays a big role in your breeding program,” says Mulliniks. “ It’s your insurance policy. But if you’re always playing catch-up on BCS post weaning, there’s something wrong – with your genetics, your timing, or your nutrition. Make sure you understand your cows’ nutritional requirements, especially during the stress periods, utilize as much good quality forage as you can, and supplement the nutritional shortages.