Characteristics of Fat from Heavy Ram and Wether Lambs

Abstract

Summary Effects of sex, diet, breed, weight group and geographical location on fatty acid composition, fat color and fat firmness were examined in a factorially arranged experiment involving 32 ram and 32 wether lambs. Thirty-two Suffolksired and 32 Rambouillet-sired lambs out of Finn x white-faced (mixed breeding) ewes were fed a high or a low energy diet at the MARC or the University of Wyoming. Lambs were slaughtered in two weight groups at 63 and 76 kilograms. Ram carcasses had softer, yellower fat than wether carcasses and lambs fed the high energy diet had softer, yellower fat than lambs fed the low energy diet. Fat from rams was higher (P<.05) in branched chain fatty acids and shorter chain fatty acids with odd numbers of carbon atoms, but lower in 16:0 and 18:0 than was fat from wethers. Feeding lambs a high energy diet also increased (P<.05) levels of odd-numbered and branched chain fatty acids. The effect of sex and diet on levels of 16:0, 18:0, odd-numbered and branched chain fatty acids appeared to be additive. Weight group, breed and location had little effect on fatty acid composition, fat firmness or fat color, but some weight x location interactions were significant.