ISSN: 2155-9600
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The response of growing Japanese quails (White Breasted line-CARI UJJWAL, n=900, divided into 36 subgroups) to three dietary levels of essential amino acids (EAA) at three different metabolizable energy (ME) levels (3×3 factorial design) on growth and immunity was investigated. Nine diets including three levels of ME (2700, 2900 and 3100 kcal/kg) each at three levels of EAA (low, medium and high) were formulated. Each diet was offered to 4 replicated groups of 25 Japanese quails up to 5 weeks of age. The ratio of lysine to protein and the level of methionine and threonine to lysine, as specified by NRC (NRC, 1994), remained almost similar in all the diets. Body weight gain, feed intake and feed conversion ratio did not differ statistically due to the treatments i.e. interaction of ME and EAA levels. However, there was linear increase in body weight gain with increased EAA levels during 0-3 or 0-5 weeks of age. Feed intake increased linearly with the decreased ME (P<0.01) and increased EAA (P<0.01) in diets. Feed conversion ratio (FCR) improved (P<0.01) linearly with increase in dietary ME concentration from 0-3, 3-5 or 0-5 weeks of age. Protein efficiency (PE) improved (P<0.01) with decreased EAA levels and also with the increase in dietary ME level during 0-3, 3-5 and 0-5 weeks of growing age, whereas energy efficiency is influenced by EAA levels during 0-3 and 3-5 weeks of age (P<0.01). Maximum performance index during 0-5 weeks of age was observed in diet with 3100 kcal ME/Kg and 115% EAA. Nitrogen retention per unit energy intake was increased (P<0.01) with the increased EAA levels and decreased energy levels. Humoral (SRBC) and cellular (PHA-P) immune response did not differ due to ME, EAA or ME x EAA. Thus, it was concluded that the optimum level of dietary ME is 2700 kcal/kg with CP 25.83%, lysine 1.49%, methionine 0.58% and threonine 1.17% on dry matter basis during 0-5 weeks of age was optimum for gain. However for optimum feed conversion, the growing quails required diet with ME 3100 kcal/kg with CP 23.23%, lysine 1.30%, methionine 0.50% and threonine 1.02% for 0-5 weeks of age.