Tempo de trânsito intestinal, desempenho, característica de carcaça e composição corporal de frangos de corte alimentados com rações isoenergéticas formuladas com diferentes níveis de óleo de soja

Abstract

RESUMO -Este estudo foi conduzido para avaliar o efeito da inclusão de 0,0; 3,3; 6,6 e 9,9% de óleo de soja em rações isoenergéticas sobre o tempo de trânsito (TT), desempenho, características de carcaça e composição corporal de frangos de Intestinal Transit Time, Performance, Carcass Characteristics and Body Composition in Broilers Fed Isoenergy Diets Formulated with Different Levels of Soybean OilABSTRACT -This study was conducted to evaluate the effect of 0.0, 3.3, 6.6, and 9.9% soybean oil inclusion in isoenergy diets on transit time (TT), performance, carcass characteristics and body composition of broilers from 21 to 56 days of age. The TT was determined at 22 and 42 days of age. Eight hundred and fourty broilers, with initial average weight of 870 g, allotted to a completely randomized design, with four treatments, six replications and 35 broilers per experimental unit, were used in the performance experiment. The TT was reduced linearly at 22 and 42 days of age. From 21 to 42 days, the levels of soybean oil showed a quadratic effect on weight gain, feed:gain ratio, energy:gain ratio and a linear effect on feed intake and energy intake. In the total period, it was observed a positive linear effect of soybean oil on weight gain, energy intake and feed intake and a quadratic effect on feed:gain and energy:gain. Abdominal fat was quadractly influenced at 42 and 56 days of age. However, carcass yield was quadractly influenced only at 56 days of age. Total body fat was positively influenced by age at 56 days and ash decreased at the same age.

Effect of lipid sources and inclusion levels in diets for broiler chickens

“…Vet. Zootec., v.66, n.2, p.519-528, 2014 However, differently from the findings in this study, some researchers have demonstrated that the level of fat addition to the diet may cause variation in the chickens' abdominal fat content (Crespo and Esteve-Garcia, 2001;Andreotti et al, 2004a), as well as the saturation level of different lipid sources (Crespo and EsteveGarcia, 2001;Crespo and Esteve-Garcia, 2002;Villaverde et al, 2005;Wongsuthavas et al, 2008;Ferrini et al, 2008). According to Ferrini et al (2008), chickens fed polyunsaturated fatty acids presented a 30% reduction of abdominal fat when compared to chickens that had saturated fatty acids.…”

“…These results are in accordance with other studies which showed that greater levels of oil added to feed benefit chickens' growth (Raber et al, 2009). Considering that the diets were isonutritive, the improvement of weight gain is due to the replacement of carbohydrate (starch) by fat, showing fat superiority in chickens' weight gain compared to carbohydrates, possibly improved by the increase of feed intake, consequently resulting in greater nutrient intake (Pucci et al, 2003;Andreotti et al, 2004a). Still, it is important to point out that oils and fats present lower caloric increase than carbohydrates during digestion, destining greater amounts of energy to maintenance and production demands.…”

“…Another factor that may influence broiler chickens' growth is the level of lipid addition to the diet as shown by Andreotti et al (2004a), who observed an improvement in the broilers' weight gain with the addition of up to 9.63% of soybean oil. However, there are few papers that evaluate the interaction between the addition level and a tested fat source.…”

Crude protein and metabolizable energy levels for layers reared in hot climates

“…Another explanation for the lower feed intake of the hens fed 3100 kcal ME/kg was the high oil content of the feeds. Under these situations, feed passage from the gizzard to the duodenum is slower because the fat digestion in the duodenum is slow (Mateos & Sell, 1981;Mateos et al, 1982;Andreotti et al, 2004) because fats need to be emulsified, thereby reducing the appetite.…”

Effect of corn oil on the digestibility and economic viability of broiler chicken feed, and on the bromatological composition of breast meat

“…In addition to physical and chemical factors related to lipids, the correct evaluation of their true energetic contribution becomes extremely difficult in birds due to the physiological difficulty they have in digesting and using them during the first few weeks of life (ANDREOTTI et al, 2004).…”