Amino Acid Supplementation into High Fat Broiler Diet for Reducing Abdominal Fat Deposition

Abstract

Fats or oils are used in poultry nutrition as source of energy, essential fatty acids and carrier of fat soluble vitamins. Most oil that used in Indonesia feed industry is palm oil that has metabolizable energy 8000 kcal kg-1. Fatty acids contained in palm oil are greatly palmitic acid of 39.23% and oleic acid of 38.21%. Palm oil utilization up to 6% do not affect abdominal fat deposition. Abdominal fat become a problem in modern broiler chicken industry. Abdominal fat do not only reduce carcass yield percentage and feed efficiency, but is also rejected by costumer. Abdominal fat might be reduced with the increasing digestibility and metabolisibility fat in the diet by amino acids supplementation. Glycine and taurine were amino acids that have role to synthesize bile salt for fat emulsification. Lysine and methionine were precursor to synthesize L-carnitine that has function to transport fatty acid for -oxidation process in mitochondria. The aim of this study was to elaborate appropriate amino acids supplementation into high fat broiler diet to improve fat absorption and metabolism in order to reduce abdominal fat deposition. This study used 240 day old broilers Cobb strain. They were placed randomly into 24 pens with density of 10 birds/m2. Broiler chickens were given feed and water ad libitum for 42 days. At 21st and 42nd day, each treatments were taken four broiler chicken come from each replication. They were slaughtered and their blood serum were taken. The treatments diet were R0 (basal diet contained 5% palm oil), R1 (R0 + 0,25% glycine), R2 (R0 + 0,25% taurine), R3 (R0 + 15% total lysine and methionine of basal diet), R4 (R0 + 0,25% glycine + 0,25% taurine), and R5 (R0 + 0,25% glycine + 0,25% taurine + 15% total lysine and methionine of basal diet). Completely randomized design (CRD) with 6 treatments and 4 replicates was used in this study. The variables measured were performances, serum metabolites, gall bladder characteristics, apparent digestion coefficient of nutrients, nutrients content of meat, and relative weight of carcass and organs broiler chicken. Data were subjected to analysis of variance and if any means significant differences were continued by Duncan multiple range test, except mortality. The results showed that all amino acids supplementation significantly reduced feed consumption, body weight and weight gain at 1-42 day old broiler chickens. Feed conversion broiler chicken for 1-42 day old fed R2 and R3 significantly increased, R1 and R4 were not significant, and R5 significantly reduced compared control. Chicken fed R3 had highest mortality than those of other groups. All supplementation of amino acids significantly increased serum uric acid and triglyceride, but significantly reduced serum cholesterol broiler chicken at 21 and 42 days old. Gall blader relative weight for 21 days fed R1 and R4 significantly increased, but fed R2 significantly increased at 42 days. All amino acid supplementations increased gall blader weight broiler chicken at 21 days, except fed R3. Whereas, broiler chicken fed R3 significantly reduced gall blader weight at 42 days. Weight and volume of bile liquid broiler chicken fed R1, R2 and R4 at significantly increased 21 days, but there were no differences at 42 days. All amino acid supplementations significantly reduced bile liquid density broiler chicken at 21 except R1, but there were no differences at 42 days. Apparent digestibility coefficient of dry matter broiler chicken for 21 days fed R1 significantly increased, nevertheless fed R1, R2 and R4 were significantly increased at 42 days. Furthermore, apparent digestibility coefficient of crude fat broiler chicken for 21 days fed R1 and R4 significantly increased, but fed R3 sigificantly reduced at 42 days. Apparent digestibility coefficient of crude protein broiler chicken for 21 days significantly increased with fed R3 and R4, but increased with fed R1 at 42 days. Apparent digestibility coefficient of energy broiler chicken for 21 days fed R3 significantly reduced. Moreover, apparent digestibility coefficient of energy fed R3 significantly reduced, R2 and R5 were not significantly different, then R1 and R4 significantly increased at 42 days. Meat dry matter broiler chicken at 21 days fed R4 and R5 significantly increased, but fed R2 and R4 significantly increased at 42 days. Meat crude protein broiler chicken at 21 days fed R2 significantly increased, but other amino acid supplementations did not effected meat crude protein broiler chicken at 21 and 42 days. Meat crude fat broiler chicken at 21 days fed R1, R3 and R5 significantly increased. Furthermore, all amino acid supplementations significantly increased meat crude fat broiler chicken at 42 days. All amino acids supplementation did not affect to relative weight of carcass, liver, and pancreas broiler chicken at 21 and 42 days. Broiler chicken given feed R3 had tendency reduced meat L-carnitine, but they fed R5 increased at 21 and 42 days old. Abdominal fat relative weight broiler chicken at 21 days fed R2 significantly increased, R1, R4 and R5 did not significant, and R3 significantly reduced. Nevertheless, all amino acid supplementations did not effect to abdominal fat relative weight at 42 days. It is concluded that mixed of supplementations of lysine and methionine (R3) could reduce abdominal fat at 21 days old from 1.30 be 0.76%. Mixed supplementation of glycine, taurine, lysine and methionine (R5) tendency improve L-carnitine meat content of broiler chicken at 21 and 42 days with each concentration 15.28 and 12.70 mg 100 g-1. Supplementations of glycine, taurine, or both mixed could improve bile liquid volume and fat apparent digestibly coefficient, especially at 21 days old. Bile liquid volume increased up to 97.10%, then fat apparent digestibly coefficient increased 2.24%.