Data are given on growth rates and levels of energy intake of 16 pairs of identical twin calves during periods when one member of each pair received a reduced energy allowance as low, in some cases, as 80 percent of a ration sufficient to maintain body weight, and its co-twin received a more liberal energy allowance. From these data, equations have been derived for the determination of energy requirements for growth and for maintenance (defined as the energy requirement of an animal that is neither gaining nor losing weight). The energy requirement of a growing animal was found to be: Energy requirement in pounds' T. D. N. = 0.0553 X pounds' bodyweight 2/3 (1+0.805Xpounds' daily gain) This equation also can be used to determine maintenance requirements (growth = 0) of young cattle. Figures 12 and 13 can be used to estimate the energy requirements of animals weighing from 200 to 800 pounds for maintenance or for growth at any reasonable rate. Energy requirements for maintenance, and for growth at various rates, are shown in table 2.We then turn to figure 12 where we find that the maintenance requirement of a 420-pound animal is Table 1. ... Age at start Duration of experiment Mean daily gain in body weight fa Mean daily energy consumption (TDN) period of restricted anbsp;...
|Title||:||Energy requirements of beef calves for maintenance and growth|
|Author||:||Clarence Floyd Winchester, Walter Anton Hendricks|