Effects of grain source, silage level, and slaughter weight endpoint on growth performance, carcass characteristics, and meat quality in Angus and Charolais steers

Abstract

2007. Effects of grain source, silage level, and slaughter weight endpoint on growth performance, carcass characteristics, and meat quality in Angus and Charolais steers. Can. J. Anim. Sci. 87: 167-180. Two growth performance trials were conducted to evaluate the effects of grain source (corn vs. barley), corn silage level (15 vs. 50%) and body weight (BW) at slaughter on growth performance, carcass characteristics, and beef quality. Gains were greater (P < 0.01) feeding corn vs. barley to Angus cattle slaughtered at 550 or 600 kg, most likely due to greater (P < 0.02) feed intakes for corn-fed cattle. Despite greater dry matter intake (DMI; P < 0.01) and feed to gain ratios (P < 0.08) with 50% silage diets, cost of production was lower (P < 0.01) feeding 50 vs. 15% silage diets. Grain source by BW endpoint interactions (P < 0.06) were present for Angus steers due to greater average daily gain (ADG) and lower feed to gain and cost of production in corn-fed cattle slaughtered at 600 versus 550 kg, while the converse was the case for barley-fed cattle. Carcass characteristics and palatability attributes were generally not affected (P > 0.05) by grain source or silage level in the diet. Grain source by silage level by slaughter endpoint interactions (P < 0.08) were present for measures of tenderness (shear force and taste panel assessment of tenderness, chewiness, and rate of breakdown). Gains were not affected (P > 0.27) by grain source for Charolais cattle, while barley feeding decreased (P < 0.10) DMI, feed to gain, and costs of production versus corn feeding. Silage level in the diet did not affect (P > 0.10) any growth performance trait in Charolais cattle. Grain source generally did not affect (P > 0.10) most carcass characteristics and shear force with the Charolais steers. The feeding of the 15% silage diet decreased (P < 0.10) measures of leanness and muscling. Many carcass characteristics were affected (P < 0.02) by slaughter endpoint in Charolais steers, with values changing as BW at slaughter increased from 600 to 700 kg. McEwen, P. L., Mandell, I. B., Brien, G. et Campbell, C. P. 2007. Incidence de la nature du grain, de la proportion d'ensilage et du poids à l'abattage sur la croissance, les paramètres de la carcasse et la qualité de la viande chez les bouvillons Angus et Charolais. Can. J. Anim. Sci. 87: 167-180. Les auteurs ont procédé à deux essais de rendement afin d'évaluer l'incidence du type de céréale (maïs c. orge), de la quantité d'ensilage de maïs (15 c. 50 %) et du poids corporel (PC) à l'abattage sur la crois-sance, les paramètres de la carcasse et la qualité de la viande. Pour les bouvillons Angus abattus au poids de 550 ou de 600 kg, le maïs assure un meilleur gain que l'orge (P < 0,01), sans doute parce que les animaux en ingéraient davantage (P < 0,02). Malgré l'ingestion d'une plus grande quantité de matière sèche (P < 0,01) et un meilleur ratio entre l'ingestion et le gain de poids (P < 0,08), l'usage d'une ration contenant 50 % d'ensilage entraîne de moins grands coûts de productio...

The growth performance and meat quality of goats fed diets based on maize or wheat grain

“…However, apart from marbling score, the proportions of moisture, protein and fat in the Longissimus dorsi muscle were not significantly different in the present study. Our results are in agreement with several studies over the past decade (Miller et al, 1996;Boles et al, 2005;Koenig and Beauchemin, 2005;McEwen et al, 2007), which found no differences in WarnerBratzler shear force measurements, and taste panel evaluations for tenderness, juiciness, and flavour when comparing beef from cattle finished on maize vs barley. Fiems et al (1999) also found that the proportion of rumen degradable starch in the diet had no effects on the proportions of moisture, protein and fat in the Longissimus thoracis muscle.…”

“…The body weight at post-weaning was greatest in calves fed a maize diet followed by those fed a wheat diet and then in those on barley and oat diets, with the differences being ascribed to differences between the cereal sources in rumen starch degradability (Khan et al, 2007). McEwen et al (2007) reported that maize-fed steers grew faster than those fed barley and suggested that differences in gain due to grain source may be due to the higher net energy values of maize vs barley. Also Tiffany and Spears (2005) attributed greater gains and better feed conversion for maize-vs barley-fed steers to lower ME in barley diets due to higher NDF concentrations.…”

“…Previous studies have demonstrated energy is the key factor for carcass and meat quality traits of meat ruminants (McEwen et al, 2007;Rhoades et al, 2007;Huuskonen, 2009). Ørskov et al (1974 a,b) found the differences in growth performance and the carcass fatty acid composition of lambs fed diets based on maize and wheat.…”

Effect of Concentrate to Roughage Ratio on Cost Effective Growth Performance of Brahman Crossbred Calves

“…The concentrate proportion in experimental diets did not affect ADG of Brahman crossbred calves, which are consistent with the results reported by McEwen [21,32] in beef steers fed on iso-nitrogenous diets of 40%-100% concentrate or McEwen and Mandell [8] in Angus steers between 70% and 35% corn level in diet. Helal et al [33] reported similar ADG (941-1,017 g) in buffalo calves fed with diets of varied concentrate levels (70%, 85% and 100%).…”

“…However, a trend towards higher gain costs was observed as grain level increased. In a trial of four iso-nitrogenous diets, cost estimates were greater (1 kg of gain) for cattle fed with the high grain or concentrate diet, and as grain levels increased, cost of gain estimates also increased [8]. Therefore, it is quite necessary to evaluate a range of C:R ratio in iso-nitrogenous and iso-caloric diets for feedlot cattle.…”