Effect of different levels of crude protein on the growth of lambs under semi intensive management system

Twelve kooka male lambs were kept under semi intensive management system to examine the effect of various levels of crude protein (CP) on the growth performance, and evaluate feed conversation ratio and economic parameters of the experiment at Sindh Agriculture University Tandojam. Three lambs of almost equal weight were allocated in each group. The experimental groups A (fed 12% CP as control); B (14% CP), C (16% CP) and D (fed 18% CP). Before start of the experiment, initial body weight was recorded and later fortnightly observations were recorded on feed consumption and resultant live body weight. The data show that feeding response lambs indicated that lambs in group C (16% CP) consumed feed (26.8 kg/lamb/fortnight), followed by group B (14% CP) and group A (12% CP) with average feed consumption of 30.5 and 35.7 kg/lamb/fortnights, respectively. The lambs in group D (18% CP) consumed average maximum feed (39.8 kg/lamb/fortnights). The live body weight of lambs which fed 16% CP was highest (40.0 kg/lamb), while the lambs in group B (14% CP) and group D (18% CP) resulted in live body weight of 35.0 kg and 36.0 kg/lamb, respectively. However, the lambs in control group A (12% CP) produced lowest live body weight of 32.0 kg/lamb. The lambs in group C (16% CP) were found to be most efficient feed converters to gain feed conversation ratio 5.5:1 followed by lambs in group B (14% CP) with 6.4:1FCR and lambs in group A (12% CP) with 8.03 :1ratio; while the lambs in group D (18% CP) remained least in FCR (7.8:1). Economic evaluation of the experiment indicated that the total cost on lambs in groups A, B, C and D, fed on rations containing 12, 14, 16 and 18% crude protein were Rs. 7350, 7200, 7000 and 7540 rupees/animal, respectively. After soling generated total income of Rs. 7800, 7900, 8400 and 7900 rupees/lamb with a net profit of Rs. 450, 700, 1400 and 559 rupees/lamb, These figures indicated that lambs in group C, fed on ration containing 16% CP had remarkably higher net profit as compared to lambs which fed 12, 14 and 18% crude protein.The results of present study suggested that the live body weight of lambs fed 16% crude protein and 70% TDN was significantly (P<0.05) higher, further increase crude protein did not prove beneficial for growth of koka lambs. The kooka lambs fed on ration contain 16% crude protein were superior in feed conversation, resulted in remarkably gained higher net profit as compared to lambs fed on 12, 14 and 18% crude protein