changes in the uropygial (preen) gland in fulani ecotype chicken (gallus gallus domestica) a post-hatch study

The uropygial (preen) gland, located dorsocranially to the pygostyle and rectrices in birds, is a bi-lobed structure responsible for secreting oil for plumage maintenance. this study investigated the morphological and histological features during post-natal development in the fulani ecotype chicken (gallus gallus domestica) with the aim of documenting anatomical information that will be useful for further biomedical and embryological studies. a total of 56 fulani ecotype chickens were sampled, and studied across four developmental phases, with each phase comprising 7 males and 7 females. for each bird, live body weight, uropygial gland weights and preen oil weights were documented. morphometric characteristics of the excised gland were documented before extraction  and measuring the preen oil. additionally, uropygial glands from selected birds per phase were excised, and fixed in 10% buffered formalin solution for gross and histological analysis. the gland appeared as early as week 2–3 post-hatch, presenting two pear shaped lobes and a short papilla. three layers of the secretory cells were recognised at 7-8 months post hatch. the results confirm that uropygial gland of the fulani ecotype chicken develops early, at week 2-3 post hatch, and that its weight increases with the body weight, reaching full histological development between 7-8 months post hatch.