Does low-protein diet improve broiler performance under heat stress conditions?

Abstract

Nutrition for broilers under high temperatures is extremely important for brazilian broiler chicken industry because the amounts of consumed nutrients and environmental temperature have great effects on bird performance and carcass quality. Among diet nutrients, protein has the highest heat increment; thus, during many years, diets with low protein level were recommended in order to reduce heat production in broiler chickens under heat stress. However, reports have shown that low-protein diets have negative effects on broiler performance when environmental temperature is high, because during heat stress, low food intake associated to a low diet protein induce amino acid deficiencies. Other studies have shown that broilers fed low-protein diets increase their energy requirement for maintenance with higher heat production. Thus, with the growth of broiler industry in tropical areas more challenges need to be faced by the farmers. So, both the ambient and nutritional conditions ought to be well managed to avoid negative effects on poultry production once they can affect the metabolism (body heat production under low temperature and body heat dissipation under high temperature) with consequence on poultry performance (meat and eggs)

Avaliação de níveis de glicina+serina em dietas de frangos de corte com reduzido teor de proteína bruta

“…Também de acordo com Furlan et al (2004), a deposição de aminoácidos na carcaça é pré-estabelecida geneticamente, não podendo ser modificada pela dieta.…”

Ajuste dos níveis de energia e proteína e suas relações para galinhas poedeiras em diferentes condições térmicas

“…De acordo com este conceito, todos os aminoácidos são proporcionalmente limitantes para o desempenho dos animais e, por esse motivo, a redução de qualquer aminoácido, independentemente do nível, pode ocasionar a sua deficiência (Furlan et al, 2004). Dessa maneira, vários estudos têm comprovado que excessos de proteína bruta na ração podem aumentar o calor metabólico e reduzir o desempenho das aves, além de aumentar a excreção de nitrogênio (Waldroup et al, 1976, Cheng et al, 1997, Aletor et al, 2000.…”

Effect of Sauropus Androgynus Leaves Extract (Sale) on Fat Deposition in Broiler Fed Low Protein Diets

“…One of the nutrients that can increase the risk of those diseases is animal fat. On the one hand, feeding low protein diets on broiler is important, because it will reduce production costs and pollution levels caused by excessive nitrogen excretion (El-Hakim et al, 2009;Hernandez et al, 2012), lower levels of air and water pollution, lower the conversion of nitrogen to ammonia gas and increase nitrogen digestibility efficiency (El-Hakim et al, 2009;Nahm, 2007) and lower levels of stress caused by heat stress (Furlan et al, 2004). Hernandez et al (2012) found that the reduction of protein levels by 1.5% or 3.0% decrease nitrogen excretion into the environment of 9.5 and 17% in male broilers, and 11.8 and 14.6% in females.…”