02032naa a2200289 a 450000100080000000500110000800800410001910000210006024501460008126000090022752012290023665000140146565000210147965000160150065000100151665000240152665000110155065000160156165000150157765000130159265000110160565300140161665300110163070000180164170000210165977300620168020781552017-10-25       1967    bl uuuu     u00u1 u    #d1 aROBERTSON, I. S.  aGrowth in castrated cattle. Growth, carcase composition and sexual development in bulls, steers and cattle castrated by Baiburtcjan's method.  c1967  aAbstract : Groups of 12 male Hereford × Friesian cattle were left entire or castrated conventionally or by Baiburtcjan's method. They were fattened mainly on concentrate from 4 months of age to a liveweight of about 940 lb. In each group 6 cattle were housed individually in stalls and the other 6 were kept in a group in a yard. Bulls gained faster than bullocks, ate less feed per unit gained and had leaner carcasses of lower grade; the Russian castrates were intermediate, resembling bullocks rather than bulls. Bulls in yards were most active but management was not difficult. A significant increase in percentage lean in the carcass of cattle in yards was the main difference found between the systems of housing. Fructose and citric acid in semen and weight and histology of genital organs showed that secretion of androgens was greatest in bulls. Most of the Russian castrates resembled bullocks but in some there were signs of androgen secretion. There was a close association between androgenic activity and lean content of carcass. Although sterility in every case was not ensured by Russian castration the method may be useful in modifying carcass composition. Bulls are most suited for production of lean meat.  aAndrogens  abody composition  aBody weight  aBulls  aCarcass composition  aCattle  aCitric acid  aEpididymis  aFructose  aSêmen  aCarcasses  aStalls1 aWILSON, J. C.1 aMORRIS, P. G. D.  tThe Veterinary Recordgv. 81, n. 4, p. 88-103, Jul. 1967.