تاثير استفاده از عوامل ليپوتروپيك بر عملكرد پاسخ هاي ايمني و و ضعيت پاتوفيزيولوژيك كبد در جوجه هاي گوشتي تغذيه شده با جيره هاي پر انرژي

چكيده انگليسي :

AbstractThe aim of present study was to investigate the effect of dietary choline and carnitine as the lipotropic agents on performance immune responses liver health and some serum biochemical parameters of broiler chicksfed diets with incremental levels of metabolizable energy ME A total of 540 day old Ross broiler chickswere randomly distributed between 9 experimental diets with 5 replicates of 12 birds each Dietary treatmentsconsisted of a 3 3 factorial arrangement with three dietary ME levels control value and 100 and 200kcal kg greater than and three situations of lipotropic factors control diet or diets supplemented with cholineor carnitine The experiment lasted 42 d and chicks had free access to feed and water throughout the trialperiod Average daily gain ADG and feed intake ADFI as well as feed conversion ratio FCR wererecorded periodically as 1 14 starter 15 28 grower and 29 42 finisher d of age Serum samples weretaken after immunization against Newcastle disease NDV and infectious bronchitis viruses IBV tomeasure antibody responses against mentioned antigens At 21 and 42 d of age sera samples were taken tomeasure blood biochemical parameters related to lipid metabolism At the end of trial two birds per replicatewere slaughtered to evaluate the carcass traits and liver fat percentage The results showed that increase indietary ME level caused P 0 05 significant increases in body weight gains during grower P 0 05 andfinisher P 0 01 periods However dietary utilization of carnitine or choline had no considerable impact onADG As expected increase in diet s ME level reduced P 0 01 feed consumption during finisher period Inaddition the least ADFI values were allotted to the chicks fed on choline supplemented diets followed bythose on carnitine diets Incremental levels of dietary ME resulted in a linear decrease P 0 01 in FCRvalues throughout the trial period Also dietary supplementation of both lipotropic factors improved FCRvalues at starter P 0 05 and finisher P 0 01 stages with the best values assigned to choline supplementedbirds Although dietary ME level had no marked effect on carcass measurements but dietary inclusion oflipotropic agents particularly choline resulted in significant decrease P 0 01 in abdominal fat and increase P 0 01 in carcass percentage Dietary choline or carnitine supplementation significantly P 0 01 reducedliver fat percentage Dietary ME level didn t affect serum high and low density lipoproteins triglyceridesand cholesterol at d 21 and 42 of age but carnitine caused a marked increase P 0 01 in serum triglyceridesat d 42 of age Carcass analysis showed that choline or carnitine didn t influence the relative weights of bursaof fabricius and spleen and antibody titers against two viral antigens while increase in ME level increased P 0 05 anti IBV antibody response Dietary supplementation of choline or carnitine decreased P 0 01 serum thiobarbituric acid reactive substance While increase in dietary ME level resulted in P 0 01 greateractivity of serum alanine aminotransferase ALT the activity of ALT P 0 05 and aspartate aminotrasferase P 0 01 were reduced as a result of introducing lipotropic agents into the diet Supplementation of lipotropic agents decreased P 0 05 serum ALT in birds fed on highest ME level Dietary inclusion of choline or carnitine elevated P 0 01 serum triiodotyronin T3 concentration Also using 100 kcal ME kg greater than control diet increased P 0 05 serum T3 but ME by lipotropic agentinteraction wasn t observed to affect thyroid activity Present findings suggest that while high energy dietsmay improve growth performance of broiler chicks dietary supplementation of choline and or carnitine couldremove unfavorable impacts of these types of diets via reducing liver fat consequently liver health and alsovia improvement of serum antioxidant capacity Keywords Broiler chicks Lipotropic agents Choline Carnitine Metabolizable energy Immune response Liver health

آزادمنش، وحيد

تاثير استفاده از عوامل ليپوتروپيك بر عملكرد پاسخ هاي ايمني و و ضعيت پاتوفيزيولوژيك كبد در جوجه هاي گوشتي تغذيه شده با جيره هاي پر انرژي

كولين , كارنيتين , انرژي قابل سوخت و سازه جيره , سلامت كبد