Select Mating Service (SMS)


Managing Recessives and Haplotypes

You want to use the best sires to reach your herd goals, but have you ever avoided good sires because they carry genetic recessives or known haplotypes? SMS helps you benefit from the genetics of these sires by using pedigree information and genetic test results to avoid carrier-to-carrier matings with any of the haplotypes or recessives listed below.

Haplotype Timing of Pregnancy Loss
HH1 All Stages
HH2 Before Day 100
HH3 Before Day 60
HH4 Unknown
HH5 Before Day 60
JH1 Before Day 60
BH1 Before Day 100
BH2 Stillborn Calves
AH1 Unknown
Recessive(1) Effect on Offspring
Brachyspina (BY) Causes abortion and stillborn calf, shortened spinal cord, long legs and abnormal organs in Holsteins
Complex Vertebral Malformation (CVM) Abortion or stillborn calf in Holsteins
Bovine Leukocyte Adhesion Deficiency (BLAD) Deficiency of a normally occurring protein needed for white blood cells or leukocytes in Holsteins
Mule Foot Hoof toes are joined, forming a single hoof in Holsteins
Spinal Muscular Atrophy (SMA) Weakness of the rear legs at three to four weeks in Brown Swiss
Fishy Off-Flavor A fishy odor in the milk of Ayrshires

Haplotype for Cholesterol Deficiency (HCD) causes young calves to die if homozygous for HCD. Unlike previous haplotypes that cause early embryo loss, this haplotype creates a greater economic loss. The defective haplotype traces back to Maughlin Storm. Storm's sire and maternal grandsire do not carry HCD. This suggests that HCD is a result of a recent mutation that first appeared in Storm or his dam. Influential descendants of Storm that also carry HCD are Stormatic, September Storm and Goldwyn. Unfortunately, the haplotype carrying the defect is difficult to track. Part of the difficulty is caused because descendants of Comestar Laurie Sheik and Comestar Outside appear to have the HCD haplotype but do not appear to produce affected calves. For animals that have the haplotype and have both Storm and Outside in their pedigrees, it's difficult to know whether they transmit the defective condition or not. Animals that don't have the haplotype will be labeled as non-carriers. Animals that have the haplotype and it's determined the haplotype came from Storm will be labeled as carriers. Those animals that have the haplotype and it's determined the haplotype came from Outside will be labeled as non-carriers. Those animals that have the haplotype and it can't be determined whether it came from Storm or Outside will be labeled as suspect.

Heterozygous (carrier) animals may have reduced cholesterol levels, but homozygotes have no cholesterol and survive only a few months after birth.

Select Mating Service (SMS), Select Sires� dairy cattle mating program, controls inbreeding depression by using parentage records and genomic testing to reduce matings of related individuals.

"Up until about ten years ago I had been mating the cows myself. But, I learned it was nice to be able to have something to fall back on if I was gone. I know the SMS evaluators are good cow people who know what I am looking for in a mating. We also started using SMS to watch for undesirable recessives and inbreeding, which was much easier with a mating program. Over time, I have become very comfortable with the matings. They make sense and the evaluators are seeing what I am seeing. We contiue to use SMS for three reasons: having another person look at the cows, to control inbreeding and to protect against recessives."

-Dave Harvatine, manager at Aurora Ridge Holsteins, Aurora, N.Y.

For more information on recessives and haplotypes, visit the Animal Health, Diseases and Recessives section of our website.

(1) World Holstein Friesian Federation, http://www.whff.info/info/geneticrecessives.php.