Beef calf weights at 100 days and 205 days as indicators of dams' producing ability

The effect of certain factors on weaning weight and weaning grade of beef cattle

“…These estimates for bull calves agree reasonably well with those of Drewry (1964). His study was carried out on the Iowa State University Angus and Hereford herds within management (creep and non-creep) with sex included in the model.…”

“…Only the subject of interactions between environmental factors affect ing weaning traits of beef calves will be reviewed. For detailed re views of the effects of environmental factors on weaning weight see Drewry (1964), Cundiff (1966) and Petty and Cartwright (1966).…”

“…This is particularly true for the interaction degrees of freedom. Drewry (1964) deducted the degrees of freedom associated with farm-year, breed and inbreeding of the dam from the between dam degrees of freedom.…”

Cow weights and other factors affecting calf weaning weight

“…However, values as high as 70 to 85 percent were also re ported by a few authors (Carter, 1956;Thatcher, 1962 produced by the same dam; they were between 0.40 to 0.55 (Koch, 1951;Rollins and Guilbert, 1954;Minyard and Dinkel, 1960;Lueker, et 1963;Drewry, 1964;Minyard and Dinkel, 1965). The correlations between full-sibs obtained in this study were slightly smaller than the repeatabilities generally reported.…”

“…Minyard and Dinkel (1960) The effect of age of dam on calf weaning weight is generally curvilinear, as pointed out by Swiger (1961). A large increase in calf weaning weight has been reported to be for calves from cows between 2 to 4 years of age (Peacock, et a^., 1960;Drewry, 1964;Rovira, 1966). Cows reached their maximum production of calf weaning weight at 6 to 9 years (Botkin and Whatley, 1953;Rollins and Guilbert, 1954;Lasley, et al, 1961;Brinks, et al, 1962;Flower, et al, 1963;Warren, et al, 1965;and Roger, ^ , 1967).…”