Studies on the nutrition of ruminants. II. The effect of level of crude fibre in maize-based rations on the carcass composition of Friesian steers

Abstract

Link to this article: http://journals.cambridge.org/abstract_S0003356100038460How to cite this article: H. Swan and G. E. Lamming (1967). Studies on the nutrition of ruminants. II. The effect of level of crude bre in maize-based rations on the carcass composition of Friesian steers. SOME effects of incorporating milled barley straw into beef fattening rations have been reported previously (Lamming, Swan and Clarke, 1966). In that work, when diets containing from 10 to 50% ground barley straw were given to yearling Friesian steers, a high rate of growth and efficient feed conversion were obtained. Carcass quality, determined by carcass measurement and visual appraisal, was not optimal, particularly in relation to fat deposition in animals receiving the highest intakes of straw. However, the method used (Agricultural Research Council, 1965a) is not sufficiently extensive to indicate the exact effect of treatment on carcass composition. Nevertheless, this information is essential, particularly where attempts are made to examine the effect of including ground roughage on the conversion of digestible energy of the complete diet into body energy, and thus to examine more critically the nature and energy cost of the live-weight gain achieved. It was therefore decided to repeat the experiments using three levels of straw inclusion which covered the range previously used, and to have carcasses dissected into bone, lean and fat. This procedure was undertaken by Messrs. T. Wall & Sons (Meat & Handy Foods) Ltd. As in the previous experiments, diets containing variable proportions of ground barley straw, ground maize and soya bean meal were fed ad libitum as cubes to Friesian steers. The results for performance and carcass dissection are recorded here. MATERIAL AND METHODS

Intensive beef production. II. Replacement of cereals with ground straw

“…The effect of metabolizable energy intake ( • • ) and energy concentration of the diet (^ O rj) on carcass gain. (^ A present experiment; • o,Swan and Lamming, 1967;• • , Lamming et al, 1966. ) …”

“…The effects of increasing the proportion of straw in the diets were similar to those found in our experiment, although overall, live-weight gains were lower. From the data of Swan and Lamming (1967) and Lamming et al (1966) we have calculated carcass gains for these experiments by assuming initial carcass weights of 144 kg (1967) and 170 kg (1966). These carcass gains, and those from our own experiment, have been plotted (Figure 1) against the metabolizable energy (ME) concentration of the diets, the latter being calculated from values for the dietary constituents suggested by the Agricultural Research Council (1965).…”

Scrotal circumference, bodyweight and serum testosterone concentration of Red Sokoto weaner bucks as influenced by dry season crop‐residue supplementation

“…It has been established that higher feed intake results in a faster rate of passage of digesta from the reticulo-rumen (Swan & Lamming 1967). This does not allow for effective degradation, hence lowering the digestibility of feed.…”

Crop-residue supplementation of pregnant does influences birth weight and weight gain of kids, daily milk yield but not the progesterone profile of Red Sokoto goats

“…It has been established that higher feed intake results in a faster rate of passage of digesta from the reticulo-rumen [8]. This does not allow for effective degradation, hence lowering the digestibility of feed.…”