21 April 1995

Herds fertility could benefit

SPECIAL protein feeding in the dry period can shorten the time from calving to first heat, says Dr David Whitaker of the University of Edinburghs Royal Dick Vet School, and Dalgetys dairy herd health and productivity service.

"There could a benefit to fertility from feeding protein in the dry period," suggested Dr Whitaker, who said fertility at service would be affected by nutrition two to three months before that.

Reproductive cycles were triggered by lutenising hormone (LH) from the pituitary gland, and his trials had shown that well fed dry cows produced more.

Dr Whitaker advised against changes at calving. Cows should calve and start lactating without changes to nutrition and social environment. That was important, as eggs were released at calving for cows inseminated at 60 days calved. If a cow was stressed metabolically or nervously at ovulation she would be less fertile.