Reduction of crude protein and supplementation of amino acids for barrows from 70 to 100kg

This experiment was carried out to evaluate the influence of crude protein (CP) reduction level of diet with amino acid supplementation on performance of barrows. A total of 48 crossbred barrows, with average initial weight of 70.12±1.56kg were used. The animals were allotted in a completely randomized experimental design with four treatments, 17.95; 16.45; 14.95; 13.45%CP, six replicates and two animals per experimental unit. The barrows were fed ad libitum during the experiment. No effect of decreasing dietary CP level on feed intake and weight gain was observed. There was a quadratic effect of the CP levels on feed:gain ratio with minimum estimated value for barrows fed 15,70% CP diet. There was no effect of CP levels on backfat thickness and lean meat. Reducing CP level from 17.95 to 13.45% in barrows diet with amino acids supplementation has no harmful effect on the performance and carcass characteristics.

amino acid; carcass; performance; finishing

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