The Effect of various Val: Lys ratio based on SID recommendation on broiler performance

The experiment were conducted to determine the appropriate ratio of digestible Val: Lys among the various recommendations. Therefore various ratios of digestible Val: Lys (SID) was examined on performance of broilers. A total 500 Ross male broiler were allocated to 5 treatments with 4 replicate and 25 birds per replicate. Treatments according to the ratio of Val: Lys including 0.74, 0.77, 0.80, 0.83 and 0.86 are included, respectively. L- valine was used only in the starter period. Corn – and soybean meal – based diets was used for grower and finisher phase. At the end of starter phase 3 birds per replicate were slaughtered to evaluate Ash, calcium and bone phosphorus. At 15 and 28 days of age, 2 birds per replicate were blood sampling for antibody titer against Newcastle disease. Regression analysis was used to appropriate ratio Val: Lys. At the end of the experiment 2 birds per replicate were slaughtered to evaluate carcass traits. There were no significant difference between treatments for traits of weight gain, feed intake, in the end of starter phase and weight gain, feed intake, feed conversion, dressing percent, breast, thighs, abdominal fat, liver and ash, phosphorus and bone calcium in the end of experiment The only significant trait was antibody on 15 day of age which showed that Val: Lys = 0.86 has highest response to antibody, therefore was significant difference with other treatments(p<0.05). As well as was determined regression response of antibody 15 day of age from quadratic response.