Níveis de triptofano digestível em rações para suínos dos 5 aos 60 kg

• Autor(a) principal: Apolônio, Lourdes Romão
• Data de Publicação: 2007
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1892
• topic: Suínos - Nutrição; Suínos - Desempenho; Triptofano na nutrição animal; Aminoácidos digestíveis; Pigs - Nutrition; Pigs - Performance; Tryptophan in animal nutrition; Digestible amino acids; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::NUTRICAO E ALIMENTACAO ANIMAL

Three experiments were conducted to evaluate the effect of dietary digestible tryptophan levels on performance and carcass protein deposition of swine from 5 to 60 kg. In the first experiment 105 crossbred piglets, males and females, weaned at 21 days of age and with average initial and final weight of 5.80 ± 0.69 kg and 15.30 ± 1.40 kg, respectively, were allotted to a completely randomized experimental block design, composed by five treatments (0.254, 0.273, 0.292, 0.310, and 0.329% of digestible tryptophan, corresponding to the relationships of 17.25, 18.50, 19.75, 21.00, and 22.75% to digestible tryptophan:lysine ratios), seven replicates and three animals per experimental unit. Quadratic effect of digestible tryptophan levels on body weight gain and feed intake was observed. Feed:gain ratio linearly decreased as the digestible tryptophan levels increased. It was concluded that the level of 0.295% of digestible tryptophan, corresponding to a relationship of 20.0% to digestible lysine, provided the best result of body weight gain for piglets from 5 to 15 kg. In the second experiment, 60 crossbred male castrated pigs, with average initial and final body weights of 15.50 ± 1,15 kg and 30.60 ± 1.35 kg, respectively, were assigned to a completely randomized experimental block design, composed by five treatments (0.149, 0.158, 0.168, 0.177, and 0.187% of digestible tryptophan), corresponding to the relationships of 16, 17, 18, 19, and 20% to digestible lysine, six replicates and two animals per experimental unit. Quadratic treatment effect on body weight gain was detected. Feed:gain ratio linearly decreased as the digestible tryptophan levels increased. It was concluded that the level of 0.175% of digestible tryptophan, corresponding to a relationship of 18.82% to digestible lysine, provide the best result of body weight gain for pigs from 15 to 30 kg. In the third experiment, 50 crossbred male castrated pigs, with average initial body weight of 29.7 ± 1,20 kg and final average weight of 60.4 ± 1,95 kg, respectively, were allotted to a completely randomized experimental block design, composed by five treatments (0.125, 0.133, 0.141, 0.149, and 0.157% of digestible tryptophan, corresponding to the relationships of 15, 16, 17, 18, and 19% to digestible lysine), five replicates and two animals per experimental unit. Linear effect of digestible tryptophan levels on body weight gain, feed intake and digestible tryptophan intake was observed. It was concluded that the level of 0.157% of digestible tryptophan, corresponding to a relationship of 19.0% to digestible lysine, provided the best performance results for piglets from 30 to 60 kg.