Growth Performance and Carcass Characteristics of Two Different Broiler Strains by Different Levels of Metabolizable Energy

Abstract

The objective of this study was to evaluate the effects of different levels of dietary ME on growth performance and carcass characteristics in two different strains of broiler chicken. A total of one thousand, 1-day-old A strain and R strain male chicks were randomly assigned into 8 treatments in a 2×4 factorial arrangement. They were fed iso-nitrogenic (CP 21%) crumbled diets formulated to contain metabolizable energy (ME) 2,950 to 3,250 kcal/kg in increment of 100 kcal/kg in the starter phase (1 to 21d) and iso-nitrogenic (CP 19%) pelleted diets containing same ME levels as in the finishing phase (22 to 38d). The body weight (BW) gain of chicks fed the lower ME diets (2,950 or 3,050 kcal/kg) were higher than those of the higher ME groups. The dietary energy level showed significant effects on feed intake and feed conversion rate (FCR) from 1 to 38 days of age (p<0.05). With the increment of dietary energy, feed intake tended to be reduced, whereas FCR was improved in the two strains of broiler chickens. The lowest FCR was observed at 3,250 kcal/kg diet groups in both of the two strains from 1 to 38 days of age. Feed intake and BW gain during 38 days were significantly affected by the strain factor. Increasing dietary energy up to 3,250 kcal/kg had no effect on the relative weights of breast meat and abdominal fat. The dietary energy and strains showed significant effects on the dressing percentage. There were no significant differences in various blood profiles except for GPT activity.

Impacts of Graded Levels of Metabolizable Energy on Growth Performance and Carcass Characteristics of Slow-Growing Yellow-Feathered Male Chickens

“…Supporting results were reported by Infante-Rodríguez et al [4], indicating that BW and ADG were not affected by the dietary energy; however, ADFI was reduced by a high caloric level, and FCR was improved with a moderate increase in dietary energy. The present results were consistent with the findings of Kim et al [29], who observed a reduced ADFI with higher energy levels than the standard diet. Other studies differed [30], where final BW and FCR in broilers increased with higher energy levels (2994 to 3013 and 3081 to 3111 kcal/kg ME, starter and finisher phases).…”

Effect of diets with different energy concentrations on growth performance, carcass characteristics and meat chemical composition of broiler chickens in dry tropics

“…In different reports on broiler chickens, there is no clear indication about the effects of energy level in diet on weight gain, feed intake or feed efficiency. In studies using diets similar to those of the current study, Tancharoenrat and Ravindran (2014) observed that an increase in energy level improved weight gain and feed conversion with no effect on feed intake, while Kim et al (2012) observed reduced feed intake with higher dietary energy. In studies with energy levels lower than those used in the present study, higher dietary ME improved broiler growth performance (Aftab 2009; Ullah et al 2012).…”

“…Others have reported similar responses in broiler chickens fed different energy levels (Nunes et al 2012; Kim et al 2012). In contrast, higher energy and protein diets increased yield of breast (Marcu et al 2013), weight of carcass and yields of breast and thigh muscle; whereas drumsticks, wings and other carcass components (head, neck, back and legs) were reduced (Marcu et al 2012b).…”

“…Several factors could have influenced the results of growth performance, carcass yield of cuts or meat chemical composition of broiler chickens fed diets with different nutrient density; one of them was genotype of broiler chickens. Kim et al (2012) reported different responses to energy concentration with different strains of broiler chickens.…”

Managing Dietary Energy Intake by Broiler Chickens to Reduce Production Costs and Improve Product Quality

“…Other authors report that changing the dietary energy content has no effect on broiler performance and carcass quality [16]. Kim et al [17] reported different responses to energy concentration with different strains of broiler chickens. The management of dietary energy intake in broiler chicken production aimed at reducing production costs and improve the product quality of broiler birds has been practiced for many decades with varying outcomes.…”