WHITE LEGHORN LAYER PERFORMANCE AFTER UROPYGIAL GLAND REMOVAL BEFORE THE AGE OF SEXUAL MATURITY

Abstract

This experiment was conducted to investigate the effect of uropygial gland removal before the age of sexual maturity on Layer performance of white Leghorn (WL) Laying hens. The study was carried out at Poultry farm of the College of Agriculture – University of Baghdad from the date of 4/5/2005 to 31/7/2006. The duration of the experiment was 15 months. A total of 180 WL pullets of 14 weeks old were randomly divided into four treatment groups. The Surgical removal for Uropygial gland (preen gland) were carried out at 16,18 and 20 weeks of age for the first three treatment groups (T1 ، T2 and T3) respectively. WL pullets at T4 were used as control group , so the uropygial gland of the hens for this group wasn't removed. Hen-Day (H.D) , Hen-House (H.H) egg production , Egg mass , and feed conversion rate (g. feed / g. egg) were measured monthly throughout of the experimental period which is lasted for 15 months. The data showed that Uropygialectomy were not significantly affected egg production , accumulative egg production and egg mass in WL Laying hens. The treatment of uropygial gland removal in age of 18 Wk. had the best feed conversion rate in age of 46-49 Wk. since the feed conversion rate for this treatment was 1.51 g. feed / g. egg in comparison with control group which the feed conversion rate for it was 2.22 g. feed / g. egg. The treatment of uropygial gland removal in age of 16 Wk. had the best feed conversion rate in age of 62-65 Wk. since the feed conversion rate for this treatment was 2.04 in comparison with control group which the feed conversion rate for it was 2.16 , while there was no significant difference between the other treatments in comparison with control group. The results can be summarize as follows : the uropygial gland removal of the WL before the age of sexual maturity had no effect on most of the productive properties of this chicken.