Effect of breed type, sex, method of rearing, winter nutrition and subsequent grazing treatment on lifetime performance and carcass composition in a 20-month beef system: carcass characteristics

Abstract

In a lifetime study of spring-born cattle in a 20-month beef system the effects of production factors on carcass characteristics were examined using 302 serially slaughtered animals born in three consecutive years. A multifactorial design was used with three animal factors — maturity (early maturing Hereford crosses v. late maturing Charolais crosses), sex (heifer v. steer) and method of rearing (suckled calves v. bucket-reared calves). After an initial rearing period, feeding treatments were imposed during the subsequent winter period, followed by the imposition of two sward heights (low 6 to 8 cm and high 8 to 10 cm) during the subsequent grazing season. An initial representative group of 16 cattle was slaughtered at the start of the grazing season and most of the remaining cattle were subsequently slaughtered off grass at three randomly allocated slaughter times, on average 67, 110 and 154 days post turn-out. Interactions between the main production factors were not significant with the exception of slaughter date with winter feeding levels for fat in rib joint and weight of saleable meat, and slaughter date and sex for live weight, carcass weight and weight of saleable meat. Breed type, sex and method of rearing affected the weight of saleable meat off grass by 14·7, 14·8 and 5·6 kg respectively. The influence of the winter feeding treatments on the weight of saleable meat was small by the time the final group were slaughtered. Sward height had a transient effect on weight, condition and carcass composition, the effects becoming less evident as the grazing season progressed. The effect of delaying slaughter had the largest and most significant influence on carcass composition of all the production factors studied, although changes in body composition between slaughter dates were relatively slow.

Beef heifer production as affected by indoor feed intensity and slaughter age when grazing semi-natural grasslands in summer

“…If there are large enough differences among feed intensities, an increased feed intensity generally results in higher liveweight gains accompanied by higher carcass weights, as well as higher conformation and fatness scores of the carcasses, but not if the differences are minimal (Aalhus et al, 1992;Steen, 1995;Steen and Kilpatrick, 1995;Steen and Robson, 1995;Steinwidder et al, 1996). Increased slaughter ages have similar effects as increased diet concentrations on carcass traits (Aalhus et al, 1992;Hinks et al, 1999). In this study, increased slaughter age with accompanied higher carcass weight resulted in higher dressing percentages (Angus heifers only), conformation scores (Charolais heifers only), and fat deposits, which is in agreement with results from earlier studies (Steen and Kilpatrick, 1995;Hinks et al, 1999; Tables 2 and 3).…”

“…Increased slaughter ages have similar effects as increased diet concentrations on carcass traits (Aalhus et al, 1992;Hinks et al, 1999). In this study, increased slaughter age with accompanied higher carcass weight resulted in higher dressing percentages (Angus heifers only), conformation scores (Charolais heifers only), and fat deposits, which is in agreement with results from earlier studies (Steen and Kilpatrick, 1995;Hinks et al, 1999; Tables 2 and 3). Increased slaughter age and feed intensity (Charolais only) decreased the retail cuts expressed as percentages of hind quarter.…”

“…4). The decrease was more pronounced for Angus heifers at the high indoor feed intensity than at the low-feed intensity, probably due to a larger rumen and intestinal fill and also a lower herbage intake on pasture by heifers previously fed at a high indoor feed intensity (Wright et al, 1986;Hinks et al, 1999). A daily decrease of 1 to 1.5 kg liveweight during the first two weeks at pasture is usual in cattle grazing semi-natural grasslands (Wright et al, 1986;Steen and Kilpatrick, 1998;Spörndly et al, 2000).…”

Keeping conditions of cattle related with health and productivity during the winter season in the north-eastern Anatolia

“…One of the main aims of cattle breeding is high productivity (7). Physical conditions and applied practice have important effect on health and productivity of cattle (13,14).…”

“…On the other hand, all the stress factors have negative effect on production (4). Inappropriate hygiene, insufficient ventilation, over stocking rate, unsuitable humidity, misbehaviour of keepers on animals and disorder of feeding-watering can be count in stress factors (1,7,13,14). Stress can restrict growth and decrease animal resistance to diseases (5).…”