Sires' own performance as an indication of progeny performance in testing Suffolk rams for growth rate

Abstract

Comparisons of performance for growth rate were made on 15 Suffolk rams and their 362 Suffolk × Welsh progeny from 2 to 16 weeks of age or to 100 lb. live-weight, whichever was earliest.The Suffolk rams were reared artificially from 7 days of age.A high negative correlation was found between growth rate and efficiency of food conversion.The correlation between the sires' growth rate and the growth rate of their progeny was 0·25. This was increased to 0·46 by limiting the performance test of progeny to the period between 8 to 16 weeks of age.Heritability estimates increased as animals grew older. An estimate of 0·52 ±0·012 was obtained for the period 8–16 weeks of age.