Genetic trend estimates for milk yield production and fertility traits of the Girolando cattle in Brazil

Genetic Trend in Milk Yield of Exotic Cattle in India

Genetic Parameters for Milk Yield and Lactation Persistency Using Random Regression Models in Girolando Cattle

A total of 32,817 test-day milk yield (TDMY) records of the first lactation of 4,056 Girolando cows daughters of 276 sires, collected from 118 herds between 2000 and 2011 were utilized to estimate the genetic parameters for TDMY via random regression models (RRM) using Legendre's polynomial functions whose orders varied from 3 to 5. In addition, nine measures of persistency in milk yield (PSi) ...

Genetic Study of Dairy Cattle and Buffalo Bulls Based on Growth, Milk Production and Reproductive Traits

The present investigation aimed to conduct a genetic study of dairy cattle and buffalo bulls based on economic traits and their phenotypic correlation. The means of various economic traits in both the species are presented. Cattle bulls reported a better libido score, Flehmen response, requirement of mounting stimulus and semen volume, conception rate and expected predicted difference for milk ...

Estimation of Economic Values for Fertility, Stillbirth and Milk Production Traits in Iranian Holstein Dairy Cows

The objective of present study was to derive the economic values for number of inseminations to conception, calving interval, milk yield and stillbirth, using economic data of 10 Iranian Holstein herds. The economic values were derived by using the profit function methods and differentiating a profit equation with respect to the traits of interest. The cow fertility costs herd amortization or r...

Genetics of milk yield and fertility traits in Holstein-Friesian cattle on large-scale Kenyan farms.

Purebred Holstein-Friesian cows are the main exotic breed used for milk production on large, medium, and small farms in Kenya. A study was undertaken on seven large-scale farms to investigate the genetic trends for milk production and fertility traits between 1986 and 1997 and the genetic relationships between the traits. This involved 3,185 records from 1,614 cows, the daughters of 253 sires. ...