Changes in connective tissue of M-semitendinosus as a response to different growth paths in steers

The effect of growth path, as opposed to advancing age, on the biophysical and biochemical properties of muscle connective tissue was investigated. Ni ne-month old Brahman-cross steers were grown across either an uninterrupted path, or paths that incorporated weight-loss and then weight gain on two d ifferent diets: one group was realimented on pasture, whilst the other was realimented on a grain-based diet. Biophysical attributes of connective tis sue toughness (Compression and Adhesion) in the semitendinosus muscle, were significantly reduced by treatment (P < 0.05). weight loss with grain real imentation being the least tough in regard to the connective tissue compone nt. Variance within the biophysical attributes was modelled statistically. Statistically significant models included terms for the post-slaughter conn ective tissue content as well as tissue contents of the enzymes lactate deh ydrogenase and isocitrate dehydrogenase. The data suggest that biochemical measurements made up to 100 days prior to slaughter, may have value as indi cators of final connective tissue toughness. (C) 1999 Elsevier Science Ltd. All rights reserved.