LIMOUSIN TODAY October 2017 | Page 37

Reproduction replacement heifers a more cost-effective proposition in the dairy industry. The first is that most dairy cattle are straightbred and highly related to mainstream purebred genetics, and there are high accuracy genetic tests available for all traits in the selection index ($NetMerit). Culling rates on modern, well- managed dairy operations tend to be low, and widespread use of sexed semen has generated an excess of replacement heifers. Dairy producers are using genomic information to make decisions such as keeping versus culling heifers, flushing exceptional heifers, breeding certain high- value heifers with sexed versus conventional semen, and breeding with dairy versus beef semen. There may be some opportunity to use genomic testing of beef heifers in analogous ways, although the value proposition will need to be considered for each operation. OCTOBER 24, 2017 Selling an Elite Set of Limousin & Other Breed Show-Heifer Prospects ONLINE SALE AT CW CATTLE SALES It is important to remember the value of crossbreeding for fitness and survival traits such as longevity, lifetime production, and reproduction rate. Improvements in cow-calf production due to heterosis result from both the improved maternal performance of the crossbred cow (conception rate, percent born alive, percent weaned, age of puberty, milk production and increased longevity) and individual performance of the crossbred calf (percent born alive, percent weaned, weaning growth). Research from the US Meat Animal Research Center (USMARC) reported that the lifetime production of reciprocal- cross and straightbred cows showed the lifetime production weight of calves weaned was increased by about 36 percent due to the effects of heterosis. This was broken down into direct effects on crossbred calf survival (+4.9%) and growth (+3.8%), and maternal effects on weaning rate (+6.2%), increased weaning weight of progeny due to the crossbred dam (+5.8%), and longevity (+16.2%) of crossbred cows. Choosing the right management tools to make genetic improvement in the beef herd is critical to economic viability. Taking advantage of heterosis, along with good sire selection decisions are proven means of positioning the herd for profitability. It is important in genetic management, as in all other management practices, to weigh the cost/ gain balance of available tools. For every d ollar invested you should expect at least an additional dollar in return. To determine what that value is in regard to commercial heifer selection using genomics is complicated and involves many factors. Under current market conditions and technologies and in the absence of any other information the value seems to be approximately $24 in retained ownership with replacement heifer operations, but closer to $10 in a market at weaning, retained heifer operation. I 20129 450th Ave. • Arlington, South Dakota 57212 www.romnlimousin.com • [email protected] ADAM, MICHELLE, GREYSON & PALMER NIELSON: 605.203.0733 • 605.203.0732 ROBERT “COOKIE” & MARY NIELSON: 605.203.0903 • 605.203.0904 ROM’N LIMOUSIN & CLUB CALVES LIMOUSIN Today | 35