Growth of bovine tissues 1. Genetic influences on growth patterns of muscle, fat and bone in young bulls

Abstract

Carcass composition and growth patterns for muscle, fat and bone were compared among 277 young male progeny of eight sire breeds, serially slaughtered at 300 kg live weight, 12 months and 15 months of age. The sire breeds were Simmental (SIM), Charolais (CHA), Danish Red and White (DRK), Romagnola (ROM), Chianina (CHI), Hereford (HER), Blonde d'Aquitaine (BDA) and Limousin (LIM). Tissue growth patterns among breeds were examined by regression estimates from the allometric growth equation (Y = ax h ) and compositional differences were estimated from the intercepts. No significant sire breed differences were found in the regression of muscle, fat or bone on various size dimensions. In regressions involving fat, however, the fattest (HER) had higher regressions and the leanest (BDA) fattened more slowly relative to muscle and bone growth. Breeds differed significantly in amount of muscle, fat and bone when compared at standard weights. Sire breed ranking for muscle at common bone weights was LIM, BDA, CHA, SIM, HER, ROM, DRK and CHI, while at common carcass weights the ranking was BDA, CHA, LIM, CHI, ROM, SIM, DRK and HER, reflecting differences in fatness. Minor changes in ranking occurred when comparisons were made at a common live weight reflecting differences in dressing percentage. For fat at standard muscle, carcass or live weight the breeds ranked HER, LIM, DRK, SIM, ROM, CHA, CHI and BDA.

Fatores que influenciam a textura da carne de novilhos Nelore e cruzados Limousin-Nelore

“…Os animais foram separados aleatoriamente em cinco grupos, compostos por cinco animais de cada grupo gené-tico. Um dos grupos foi abatido no início do experimento e os demais permaneceram em sistema de criação em pasto, com suplementação nutricional, sendo abatidos de forma seriada ao longo de 204 dias, possibilitando a obtenção de animais em faixas crescentes de peso (Berg et al, 1978).…”

Adipose tissue growth, distribution and cellularity in steers of two biological types

“…In this regard, Mukhoty and Berg (1971) and Charles and Johnson (1976) reported breed differences in the rate of fat deposition, but Berg et al (1978a), working with breeds classified as late fattening, reported homogeneous allometric regression coefficients for fat deposition among sire breed groups.…”

“…Kempster et al (1976a), working with differ ent breeds, and Berg et al (1978a), using cattle of the three sexes, reported an increase in the ratio of subcutaneous: intermuscular fat with fattening. The discrepancies may be explained by differences in the cattle used and by the inclu sion of omental and mesenteric fat depots in our study.…”

“…However, more recent work by Berg et al (1978a) with European breeds of cattle concluded that breeds differed in the amount of total fat adjusted to a common side weight but no differ ences were found in the rate of fattening among breeds.…”

Estudo alométrico em codornas para corte alimentadas com treonina digestível

“…O tecido ósseo apresenta maior impulso de crescimento em menor idade, enquanto o tecido adiposo tem crescimento em idade mais avançada e o tecido muscular, em idade intermediária (Berg et al, 1978;Müller e Primo, 1986 (2012) com codornas de corte machos e fêmeas abatidas em diferentes idades, houve efeito no desenvolvimento alométrico para o desenvolvimento do osso do peito e da asa para os machos na idade de 35 dias, os quais apresentaram desenvolvimentos precoces (b<1) dado semelhante ao encontrado no presente estudo.…”