قابليت هضم چربي‌ها، غلظت اجزاي چربي و هورمون‌هاي استروئيدي در سرم خون و ذخيره و الگوي توزيع چربي در لاشۀ مرغ‌هاي گوشتي تغذيه‌شده با جيره‌هاي حاوي كارواكرول، منتول و تيمول

Lipids digestibility, blood serum concentrations of fat constituents and steroid hormones, carcass fat deposition and distribution pattern in broiler chickens fed carvacrol, menthol and thymol supplemented diets

اين پژوهش براي بررسي و ارزيابي تأثير افزودن مقادير 400، 200 و 200 ميلي‌گرم در كيلوگرم به ترتيب از كارواكرول، تيمول و منتول به يك جيرۀ شاهد بدون افزودني بر ذخيره و توزيع چربي در لاشۀ جوجه ­هاي گوشتي با استفاده از 96 قطعه جوجۀ گوشتي ماده از سن 12 تا 42 روزگي اجرا شد. افزودن كارواكرول، منتول و تيمول به جيره به ترتيب موجب كاهش معني­داري در قابليت هضم ايلئومي چربي خام به ميزان 8/02، 5/06 و 15/08 درصد شد (0/01p)، چربي گردن (0/05>p)، چربي زيرپوست (0/05p). بنابر نتايج اين آزمايش به نظر مي­رسد كه كارواكرول و تيمول موجب كاهش قابليت هضم ايلئومي چربي و كاهش چربي لاشۀ مرغ به‌ويژه در بخش چربي زيرپوستي مي­ شوند.

This research was conducted to examine the effect of addition 400, 200 and 200 mg/kg carvacrol, menthol and thymol, respectively, to a non- supplemented control diet on carcass fat deposition and distribution pattern in broilers. 96 female Ross 308 broiler chicks were used in 4 treatments and 12 replicates of two birds in each from 14 to 42 days of age. Ileal fat digestibility was decreased by 8.02, 5.06 and 15.08 percent in the birds receiving carvacrol-, menthol- and thymol-supplemented diets, respectively (P<0.01). The meanof carcass fat and feather fat percentage was reduced in the birds fed diets containing carvacrol by 6.08 and 31.57 percent, respectively, in comparison to control (P<0.05). The addition of carvacrol to diet resulted in 6.86 (P>0.05), 6.95 (P>0.05), 38.01 and 10.50 (P<0.05) percent reduction in abdominal, neck, subcutaneous and thigh intramuscular fat deposits, respectively. The back fat thickness of chicks receiving diets containing carvacrol, thymol and menthol was significantly (P<0.05) lower than that of control group. The blood serum concentration and ratio of estradiol, dehydroepiandrosterone, testosterone, cortisol and progesterone of chicks fed diets containing carvacrol, thymol and menthol had no significant difference with control (P>0.05). According to the results of this study, it seems that carvacrol and thymol will result to reduction in ileal fat digestibility and carcass fat of broilers especially in subcutaneous fat.