Some factors affecting yellow fat colour in cattle

J.H.L. Morgan, F.S. Pickering and G.C. Everitt

Ruakura Agricultural Research Centre, Hamilton

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Proceedings of the New Zealand Society of Animal Production. 1969, 29: 164-175

Fat colour intensity and carotene levels were higher in the Jersey than in Friesian and Aberdeen Angus cattle. Jersey crosses with Friesian, Charolais and Hereford sires were generally intermediate in fat colour with evidence that the Charolais sire was more effective than the Hereford in reducing the. colour. Appreciable variations within all breeds and crosses, especially in the Jersey, was observed with considerable overlap in breed distributions.

Neither colour intensity of fat, nor blood and fat carotene levels, were closely related to animal age, with no evidence of a sex effect.

Carotene levels in blood, channel and subcutaneous fat, and fat colour intensity, were all positively correlated but could not be reliably predicted from each other.

On carcass chilling, fat colour increased with surface drying but decreased with cooling of fat, the net result being largely dependent on chiller temperature. Rendering of fat did not eliminate the yellow coloration.

It was concluded that genetic. manipulation such as within-breed selection, cross-breeding and breed replacement can effectively reduce fat colour and largely eliminate the marketing problem of yellow fat.

Keywords: NZSAPAB;