The effect of short-term fasting on performance traits and rectal temperature of broilers during the summer season

Abstract

1. The present study was conducted to determine if detrimental effects of high temperature on broiler performance could be overcome by short-term fasting and to examine the effect of food withdrawal on the responses of two commercial strains (S1 and S2). 2. An experimental design was used with three feeding groups and two strains. Birds in the control (C) group were fed ad libitum during the experimental period (0 to 6 weeks), while feed was withdrawn in the other groups between 10:00 and 16:00 h during weeks 5 and 6 (F1) or week 6 (F2), respectively. After standard brooding for the first 3 weeks temperature and humidity varied according to outside climate between 4 and 6 weeks of age. 3. Feeding strategy significantly affected body weight at week 6 (BW6) and daily weight gain during week 6 (DWG5-6). F2 gave the best results in BW6 and DWG5-6. Strain effect was significant on DWG4-5 and DWG5-6; S1 had higher DWG4-5 and S2 gained more at the last stage. S1C broilers had greater BW6 than S2C but the S2 strain gave a better response to short-term fasting compared with S1 and this resulted in significant strain by feeding interaction effect on BW6 and DWG5-6. 4. It was shown that short-term fasting was an effective method for controlling rectal temperature (RT) of broilers at 5 and 6 weeks of age. 5. Total food consumption (FCO-6), food conversion ratio (FCRO-6), mortality, and carcase characteristics were not affected by short-term fasting in the experimental conditions. 6. In conclusion, it can be recommended that broiler producers may practise 6 h of fasting during the hot period of the day without any adverse effect on slaughter weight and FCR when the birds are close to the average slaughter weight and a heat wave is expected. Strain differences in RT measurements also indicate the importance of choosing strains to be used in hot and warm climate conditions with attention to the thermoregulation ability of broilers.

Is sequential feeding a suitable technique to compensate for the negative effects of a tropical climate in finishing broilers?

“…Depending on the actual temperature endured by the chickens, the technique may have positive [10,5] or negative (present work) effects on growth and feed conversion. In general when the environmental conditions induce mortality (i.e., Ta > 33 °C for several hours during several consecutive days and Tb of some birds overpasses 44 °C, above which level survival is compromised) the feed withdrawal techniques show positive effects on overall performances.…”

The response of Ross 308 and Hybro broiler chickens to early and late skip-a-day feed restriction

“…Genetic potential not only affects the growth response and body composition of the bird because of its effects on nutrient requirements (Havenstein et al 1993;Gous et al 1999) but also affects compensatory growth of broilers subjected to feed restriction (Yu et al 1990). Ozkan et al (2003) reported significant strain as well as strain | feeding regime interaction effects on body weight and weight gain when two strains were subject to short-term early feed restriction. Also, Rosa et al (2007) reported significantly better performance and carcass yield and lower abdominal fat deposition in AgRoss 308, a commercial line than PCLC, a non-improved line and a significant interaction between genetic group and dietary metabolizable energy level for feed conversion.…”

Adaptation to hot climate and strategies to alleviate heat stress in livestock production

“…In poultry, temporary feed restriction before or during heat exposure is found to be an effective way to improve heat resistance by lowering metabolic heat production (Amand et al, 2004). In Turkey, Ozkan et al (2003) showed that feed withdrawal during the hottest period of the day reduced mortality without any negative effect on growth performance. Similar results were recently reported by De Basilio et al (2010).…”