Dietry protein and energy requirements of meat type Japanese quail for growth

Abstract

A three square factorial experiment designed to study the dietary requirments of protein and energy for meat type Japanese quail (Coturnix coturnix japonica) for growth, under the hot-humid conditions of Kerala is presented in this thesis. Quail chicks of seven day old age were obtained in three batches at three weeks interval between batches. Each batch consisted of 324 quail chicks and were obtained from the same source in order to keep the genetic make up constant. The birds were randomly allotted to nine dietary protein-energy combination groups. The dietary protein levels employed were 22, 24 and 26 per cent and that of energy level were 2700, 2900 and 3100 Kcal ME/kg diet. General observations were made for three, six week periods. The body weight at fifth and sixth week of age was not influenced by the dietary levels of protein or energy used in the study. Whereas body weight at the earlier ages were influenced (p<0.01) by the dietary treatments. Higher dietary protein levels of 24 and 26 per cent resulted in significantly heavier (p<0.01) body weight. The body weight was found to be decreased with increase in energy levels in the diet. The body weight gains were no influenced by the dietary treatments except at the second week of age. The overall weight gain from 1 to 5 and 1 to 6 weeks of age revealed that both protein and energy influenced the character significantly (p<0.01). The feed consumption data reiterated the already established fact that feed intake is regulated more by the energy level rather than protein levels in the diet. The overall consumption from 1 to 5 and 1 to 6 weeks of age revealed that the protein levels did not influence the feed consumption whereas energy levels influenced. The feed efficiency in earlier ages was significantly (p<0.01) better with higher protein diet, but from fourth week of age it was inconsistent. However, the overall feed efficiency from 1 to 5 as well as 1 to 6 weeks of age indicated statistically superior ( The processing data both at fifth and sixth week of age were not influenced by the levels of the protein, energy or both employed in the study. The ready to cook yield and total offal at fifth week of age averaged 75.47 and 24.53 per cent respectively and those at sixth week of age were 77.78 and 22.22 per cent respectively. The breast constituted the highest followed by back, thigh, drumstick, wing and neck among the cut-up-parts at both ages. The meat-borne ratio at fifth and sixth week of age averaged 1.90 with range of 1.81 to 2.05 and 1.98 with a range of 1.93 to 2.05 respectively. The liver protein progressively increased with increase in protein content and liver lipid increased with increase in energy levels in the diet during both five and six weeks of age. Similar trend was observed in the case of serum protein and lipid at both these ages. The haemoglobin levels were not influenced by the treatments. Even though the values obtained on carcass analysis were well with in the normal biological limits, the ether extractive per cent at fifth and sixth week of ages were influenced (p<0.01) by the dietary treatments. All the birds showed a positive nitrogen balance irrespective of the protein or energy levels in the diet. Extremely poor deposition of abdominal fat in quails slaughtered at both these ages was observed. Even though the results of weekly body weight and weight gain tend to suggest a two stage requirement namely one from one week to three week of age and the other from four week of age down, the absence of any significant influence by either protein or energy levels in the diet on body weight at fifth and sixth week of age does not provide sufficient rationale for such suggestion. But the overall feed efficiency from initial to either fifth or sixth week did show significant influence of dietary protein levels, higher level of 26 per cent being superior over other levels. Thus it appears to set the energy and protein requirement at 2700 Kcal ME/kg diet and 26 per cent respectively. The better feed efficiency at fifth week of age when compared to sixth week of age and also the absence of any statistically significant difference in slaughter characteristics between fifth and sixth week of age tend to suggest fifth week of age as ideal age of slaughter.