Characterization of beef cattle breeds by virtue of their performances in the National Beef Cattle Performance and Progeny Testing Scheme

Abstract

Average growth and body weight data, which comprised 745 400 weaning records and 14 990 Phase C growth records of young bulls of 16 breeds were obtained from the National Beef Cattle Performance and Progeny Testing Scheme and used in this re-analysis to characterize breeds for a variety of important traits. Phenotypically, mature breed size (X) was found to be significantly related to birth weight (Y = 2.85 + 0.066X), weaning weight (Y = 25.8 + 0.369X) and growth rate (Y = 320 + 2.28X). Nevertheless, some breeds deviate considerably from their predicted values. Productive efficiency was, however, unrelated to mature breed size and dual-purpose breeds tended to be the most efficient. They were also the breeds showing the highest degree of sexual dimorphism.

Gemiddelde groei-en liggaamsgewigdata, wat 745 400 speenrekords en 14 990 Fase C groeirekords van jong bulle ingesluit het, is van 16 rasse van die Nasionale Vleisbeesprestasie- en Nageslagstoetsskema verkry en herontleed ten einde die rasse vir 'n verskeidenheid van belangrike eienskappe te karakteriseer. Daar is aangedui dat geboortegewig (Y = 2.85 + 0.066X), speengewig (Y = 25.8 + 0.369X) en groeitempo (Y = 320 + 2.28X) fenotipies betekenisvol met ras volwasse gewig verband hou. Tog wyk 'n aantal rasse aansienlik van hulle voorspelde waardes af. Produksiedoeltreffendheid is egter onafhanklik van ras volwasse grootte en dubbeldoel rasse het geneig om die doeltreffendste te wees. Dit was ook die rasse wat die hoogste mate van geslagtelike dimorfisme getoon het.

Keywords: Beef cattle, breeds, characterization, growth, productive, efficiency