“Slick” gene helps cattle beat the heat

Nov 11, 2008
“Slick” gene helps cattle beat the heat

Pinpointing the chromo somal location of the Aslick@ gene identified by Agricul tural Research Service (ARS) scientists could help breeders develop cattle with shorter, slick hair that helps keep them cool in the sub tropical heat. In central Florida, exces sive summer heat can take its toll on cattle, leading to reduced milk production from dairy cattle and higher death rates among beef cattle. But the discovery of the slick gene by scientists at the ARS Subtropical Ag ricultural Research Station in Brooksville, FL, should help deal with these heat related issues.

Breeders could move the gene into other economically important breeds, such as Holstein or Angus, to im prove their heat tolerance.

The black-and-white Hol stein is the world’s top-pro ducing dairy animal. The typical Holstein herd pro duces more than 21,000 pounds of milk, 775 pounds of butterfat, and 683 pounds of protein per year. Angus is the most popu lar beef breed in the U.S., with more than 350,000 Angus cattle registered.

They are hardy, undemand ing and adaptable, and have a high carcass yield of marbled meat—the amount of intramuscular fat that gives the meat its marble pattern appearance—a highly sought trait in the meat industry.

Studies at Brooksville led by animal scientist Chad Chase have shown slick-haired animals to have internal tempera tures about 1 degree Fahr enheit lower during the summer than other cattle with normal hair coats.

Mapping the gene’s loca tion on the chromosome is the first step towards iden tifying the mutation re sponsible for the shorter, slick hair. These results suggest a role for marker-assisted selection to identify bulls that will produce only slick haired progeny. Some Se nepol bulls were tested us ing these markers, and the results indicated excellent potential for identifying bulls that will produce only slick-haired offspring. The same gene also appears to be responsible for the slick hair coat in Romosinuano cattle. — WLJ