Effects of feeding varying dietary crude protein and digestible energy concentrations on performance of pigs raised in a humid tropical environment

This paper aims at investigating relationships and effects of varying protein and energy levels on growth performance, efficiency of feed conversion and efficiency of nutrient utilization of weanling pigs fed from of 9 to 60kg. A total of one hundred and twenty weanling pigs weighing ± 9kg were allotted randomly to sixteen groups of eight pigs each. for females and four castrated males in a 4x 4factorial design. The sixteen diets consist of four digestible energy levels (3,000: 3300: 3,600 and 3,900 kcal/kg) and four crude protein levels (18; 21: 24 and 27%). The pigs were fed these experimental diets until they attained a predetermined liveweight of 60 +1.5 kg. The effects of the varying crude protein and digestible energy were studied on growth and performance parameters Neither protein nor energy levels significantly affected daily feed intake, but significantly decreased daily feed intake at 27protein level. Daily protein intake was influenced by protein intake and digestible energy intake was also significantly influenced by digestible energy intake. There were no significant interactions between protein and energy levels with respect to feed intake and intake of protein and energy Energy but no protein levels significantly influenced rate of live weight gain. Feed conversion efficiency (FEC) was highly (P 0.001) influenced by energy but not protein levels. In both sexes, females and castrated males, increasing dietary levels of protein and energy resulted in improved efficiency of feed utilization within protein levels but there were significant differences between the two highest energy levels for castrated males and within the diets with 3.300, 3.600 and 3.900 kcal/DE/kg for the females. When high protein levels were combined with high energy levels feed intakes were depressed only on the 279% protein level. Feed conversion efficiency was maximized on the diet with 21 and 249% protein levels with appreciable sex diferences, with female pigs requiring more protein than males. Digestible Energy range of 3,300 and 3,600 kcalkg would be adequate for maximum gain and efficiency of feed utilization in pigs under the humid tropical environment tropical. Feed to gain ratio, a very important economic index should be an important index of the quality of any diet for promoting growth.