Sire by Herd Interaction in Production Traits in Dairy Cattle

Sire x herd interactions for weaning weight in beef cattle.

Weaning weight records of 44,357 Australian Angus calves produced by 1,020 sires in 90 herds were used to evaluate the importance of sire x herd interactions. Models fitted fixed effects of contemporary group (herd-year-date of weighing subclass), sex, calf age, and dam age and random effects of sire or of sire and sire x herd interaction using REML. Effects of standardizing the data, including...

The frequency of photosensitization in a dairy cattle herd infected by Leptospires

Leptospirosis is a bacterial zoonotic disease, which can induce hepatic lesions. Photosensitization (PS)maybe is the result of accumulation of photodynamic agents in unpigmented area of the skin exposed tosunlight which occurred due to hepatic lesions. An outbreak of leptospirosis was occurred in a dairy cattleherd complex with 760 dairy milking cows in March (1990). Totally, 412 cows (54.21%) ...

Genotype by Environment Interaction for Automated and Traditional Fertility Traits in Dairy Cattle

estimation of genotype by environment interaction for production traits in iranian holstein cattle

in order to evaluation of genotype by environment interactions in holstein cows, iran was divided into cold, middle cold, temperate and hot climate regions. for this purpose used from 39570, 35813 and 18955 records for milk, fat and protein yields, respectively, to progeny test for 35 sires that have 50 daughters in each climate. the data were collected by the centre of breeding and improvement...

Sire X environment interactions for growth traits of Hereford cattle.

Twelve Hereford bulls were used to sire calves in each of three locations in North Carolina over 6 yr. Three bulls were bred artificially to a random one-third of the cows at each location each year. Locations represented the Mountain, Piedmont and Coastal Plain regions of the Southeast. As yearlings, steer progeny were fed a concentrate diet in a feedlot or grazed on pasture and then slaughter...