Effect of feed restriction on the maintenance energy requirement of broiler breeders.

Ferreira da Silva Teofilo, Guilherme; Riveros Lizana, Rony; de Souza Camargos, Rosiane; Balbino Leme, Bruno; Horna Morillo, Freddy Alexander; Lucas Silva, Raully; Kochenborger Fernandes, João Batista; Kazue Sakomura, Nilva

Objective: This study aimed to evaluate the effect of the ad libitum and restricted feeding regimen on fasting heat production (FHP) and body composition. Methods: Twelve Hubbard broilers breeders were selected with the same body weight and submitted in two feeding regimes: Restricted (T1) with feed intake of 150 g/bird/d and ad libitum (T2). The birds were randomly distributed on the treatments in two runs with three replications per treatment (per run). The birds were adapted to the feed regimens for ten days. After that, they were allocated in the open-circuit chambers and kept for three days for adaptation. On the last day, oxygen consumption (VO2) and carbon dioxide production (VCO2) were measured by 30 h under fasting. The respiratory quotient (RQ) was calculated as the VCO2/VO2 ratio, and the heat production (HP) was obtained using the Brower equation (1985). The FHP was estimated throughout the plateau of HP 12 hours after the feed deprivation. The body composition was analyzed by dual-energy X-ray absorptiometry scanning at the end of each period. Data were analyzed for one-way analysis of variance using the Minitab software. Results: The daily feed intake was 30 g higher to T2 (p0.75/d) and CO2 production ( 2.2 L/kg0.75/d). That resulted in a higher FHP 359±14 kJ/kg0.75/d for T2 than T1 296±17.23 kJ/kg0.75/d. In contrast, the RQ was not different between treatments, with an average of 0.77 for the fasting condition. In addition, protein and fat composition were not affected by the treatment, while a tendency (p<0.1) was shown to higher bone mineral content on the T1. Conclusion: The birds under ad libitum feeding had a higher maintenance energy requirement but their body composition was not affected compared to restricted feeding.

DUAL-energy X-ray absorptiometry; BODY composition; ONE-way analysis of variance; OXYGEN consumption; RESPIRATORY quotient; BODY weight

Animal Bioscience, 2022, Vol 35, Issue 5, p690

2765-0189

Academic Journal

10.5713/ab.21.0183