NEUROPATHY WITH SPLAYED FORELIMBS (JNS)

The list below contains sires from the Select Sires, Accelerated Genetics and GenerVations lineups that are carriers for JNS.

The American Jersey Cattle Association (AJCA) recently shared news of a new undesirable trait known as Jersey Neuropathy with Splayed Forelimbs or JNS. Select Sires is working closely with the AJCA and researchers from USDA-AGIL to learn about this new undesirable trait. As your cooperative, we will continue to support you and provide you with the most up-to-date information.

Genetic research and genomic testing are more prevalent than ever before. As technology advances and we test more cattle, we will continue to make these types of genetic discoveries. While it is likely that many sires will carry this undesirable trait, we have the available genetic information and breeding strategies to avoid its impact. By using genetic test results, pedigree information and guidance from your Select Mating Service® (SMS®) genetic consultant, you can avoid carrier-to-carrier matings and successfully manage undesirable traits. This breeding strategy avoids economic loss while continuing to utilize the industry’s best genetics.

7JE1617 JX KIAWA {6}-P

7JE1831 ENSIGN

7JE5004 CHROME

250JE1793 CANDYMAN

507JE1930 DABO-P

614JE2083 SEISMIC-PP

ARTHROGRYPOSIS MULTIPLEX CONGENITA (AM)

A New Genetic Defect in Ayrshires

A new genetic defect was recently reported in the Ayrshire breed. The condition is called arthrogryposis multiplex congenita (AM) and is commonly referred to as “curly calf.” The defect causes malformation of affected calves where the legs are severely curved with stiff joints. The calves are stillborn and most often cause calving difficulties. The condition is inherited as an autosomal recessive.

The condition was first reported by researchers in Denmark based on cases of deformed calves in the Swedish Red breed. It appears the source animal for AM is the Swedish Red sire Peterslund. The frequency of carrier animals is estimated to be about 12 percent in the U.S. Ayrshire population and is approaching 20 percent in Canadian Ayrshires.

The carrier status of an animal can be identified with reasonable accuracy from genomic test results. CDCB has begun providing these results for genomic tested animals. In addition, assays that directly test for the mutation that causes AM are available from several DNA testing labs. Select Sires has completed the gene test on all our Ayrshire bulls with Peterslund in their pedigree and we have ONE current Ayrshire AM carrier: 9AY136 CHAOS.

We have submitted all other Ayrshire sires with semen available for AM testing but we do not anticipate identifying any additional carriers. A complete list of haplotype calls and/or gene test results will be reported along with the April 2023 genetic evaluations.

As previously noted, AM is inherited as a recessive trait. By using genetic test results and avoiding carrier by carrier matings, creating animals affected by AM can be completely avoided. This strategy avoids the economic loss caused by AM and allows our customers to continue to use the industry’s best genetics.

A similar condition also called “curly calf” has been reported in the Angus breed but the Angus version is caused by a mutation in a different gene located on a different chromosome.