Histological changes which occurred in the cervix of the ovariectomized rabbits without hormone and with hormones injection were investigated.             A total of 45 female rabbits were divided into three groups, the first group was used as a control, while, the second and third groups were used for experiments.             In control group the tunica mucosa thrown into branched folds which lined with simple cuboidal to columnar epithelium, and a lamina propria was well vascular dense irregular collagenous connective tissue and a tunica muscularis displayed double layers of smooth muscle fibers. In ovariectomized group without hormones injection, the tunica mucosa showed delicate mucosal folds which lined with low simple cuboidal epithelium and the tunica muscularis was very thin layer, and a significant decreased in the height and thickness of mucosal folds, thickness of lamina propria and tunica muscularis. In ovariectomized groups with hormones injection, the cervix was very thick walled organ and their mucosal folds were the tallest, pyramidal shaped and their epithelium turned into simple columnar epithelium. The thickness of tunica muscularis was increased due to their two layers those intermingled with much of collagen bundles. Statistically, a significant (P<0.05) increased in the values of all parameters.             The present study concluded that that cervix in doe has a narrower lumen with huge collagenous connective tissue content that increased in response to steroid hormones, in addition to hyperplasia and hypertrophy, consequently for keeping intrauterine during the preimplantation stage and pregnancy.

The present study aimed to investigate the esophagus's anatomical, histometrical, histochemical aspects in the Ring-necked parakeet and Black-shouldered Kite. The esophagus in the parakeet was shorter and narrower than the kite esophagus. The crop was a well-developed sac shape in the parakeet, while the crop was hardly recognizable in the kite. Histological study shows that the esophagus in both species was composed of four layers arranged from inner to outer (mucosa, submucosa, musculosa, finally serosa). These layers showed variances in the height of the fold, the glands number, and the wall layers' thickness. The mucosa in the esophagus of the kite consisted of non-keratinized stratified squamous epithelium, while in the parakeet, mucosa consisted of keratinized stratified squamous epithelium. The esophageal glands were compound tubuloalveolar in the parakeet, while in the kite, there were simple alveolar glands. The folds in the kite were longest and contained more esophageal glands, while the parakeet glands were more prominent and had fewer numbers within the submucosa. The submucosa layer in the parakeet was thicker than that of the kite. The histochemical results showed a positive reaction of esophageal glands with Alcian blue (PH 2.5), while reacting negatively with Periodic Acid Schiff (PAS) stains due to the acidic mucopolysaccharides secretions nature.