Exigência de metionina mais cistina para codornas japonesas em crescimento

Abstract

RESUMO -Foram utilizadas 540 codornas fêmeas, com idade inicial de sete dias e peso médio de 21,50 g, durante 35 dias. O delineamento foi em blocos ao acaso, com cinco repetições e 18 aves por unidade experimental. Os tratamentos consistiram de seis relações metionina mais cistina digestível: lisina digestível (0,48, 0,53, 0,58, 0,63, 0,68 e 0,75). Foram estudadas as variáveis peso final (g), ganho de peso (g), consumo alimentar (g), conversão alimentar (g/g), empenamento (%), composição química corporal (matéria seca, água, proteína e extrato etéreo) e deposição de proteína e gordura corporais. Os tratamentos influenciaram de forma quadrática o consumo alimentar, a conversão alimentar, o empenamento, a composição química (matéria seca, água, proteína e extrato etéreo) e a deposição de proteína corporal, e linearmente o peso final e o ganho de peso das codornas. A melhor relação metionina mais cistina digestível: lisina digestível para as codornas japonesas em crescimento foi de 0,66, sendo a exigência em metionina mais cistina digestível estimada em 0,758%, para consumo de 91,43 mg de metionina mais cistina digestível.Palavras-chave: aminoácidos sulfurosos, codornas japonesas de postura, Coturnix coturnix japonica, digestibilidade, proteína ideal Methionine plus Cystine Requirement for Growing Japanese QuailsABSTRACT -Five hundred and forty 7-days old female quails, averaging 21.50 g, were used during 35 days. A completely randomized blocks design with five replicates and 18 females per experimental unity was used to study the effect of six digestible methionine plus cystine: digestible lysine ratios (0.48, 0.53, 0.58, 0.63, 0.68 and 0.75) on the traits evaluated during the growing period. Final weight (g), weight gain (g), feed intake (g), feed conversion (g/g), feather rate (%), chemical composition (%) (dry matter, water, crude protein and ether extract) and body protein and fat deposition (g). The effect of the amino acids on feed intake (g), feed conversion (g/g), feather rate (%), chemical composition (%) (dry matter, water, crud protein and ether extract) and protein deposition was quadratic and the effect on final body weight (g) and weight gain (g) was linear. The best estimated digestible methionine plus cystine: digestible lysine ratio was .66 and the estimated digestible methionine plus cystine requirement for growing Japanese quail was .758%, for a intake of 91.43 mg of digestible methionine plus cystine intake.

Ideal ratio of digestible methionine plus cystine to digestible lysine for growing Japanese quails

“…Thereafter, birds no longer require artificial heating because they present good feathering at the optimum maximum and minimum temperatures of 31 °C and 19 °C, respectively, with 60 to 65% relative humidity (Vohra, 1971;Reis, 1980;Singh and Narayam, 2002;Pinto et al ., 2003;Oliveira, 2004). In the adult phase (data from 41 to 100 days of age) the thermal comfort zone of quails is within 18 and 22 °C and air relative humidity is between 65 and 70% (Oliveira, 2004).…”

“…The diets were iso-caloric and iso-nitrogen. The ratios between amino acids and lysine proposed by NRC (1994) were maintained, except for methionine + cystine to lysine, which varied according to the recommendation by Pinto et al (2003). To make sure the diet was not deficient in any amino acid, 3% was added for each amino acid requirement, except for methionine + cystine and digestible lysine.…”

“…For the calculation of body fat and protein deposits, the value found in the sample was compared with the average weight of the live animal in each experimental unit, according to Pinto et al (2003).…”

“…Most research has focused on the nutritional requirements of quails during the laying phase and there is little information about requirements during the growing phase. Quails are characterized by early sexual maturity (40 days), demanding feeding programs that maximize growth by combining body development with sexual maturity, thus allowing uniformity of breeding stock and productivity (Pinto et al ., 2003).…”

Expressão gênica de IGF-I e GHR no fígado e no músculo do peito de codornas de corte suplementadas com diferentes níveis de metionina em duas gerações sucessivas

“…Porém, observa-se que as aves que nunca receberam metionina na dieta tiveram um pior ganho de peso. Os resultados estão de acordo com Belo (1997) e Pinto et al (2003), que também não observaram efeito dos aminoácidos sulfurosos sobre o peso final em codornas de postura.…”