Microscopic and morphometric study of the proventriculus and ventriculus of the Striated Scope Owl (Otus Scors brucei) in Iraq

The stomach of the Striated Scope Owl (OtusScorsbrucei) consist of two externally distinguishable chambers: that are the proventriculus (glandular part which secretes the gastric juices) and the gizzard (ventriculus) which has a mechanical function. The proventriculus of longitudinal shape is cranially continuous with the esophagus. The gizzard was rounded shape with a thin wall is extended caudally to the proventriculus. The proventriculus was thick-walled and short (the mean length was 11.4mm , 7.1mm in diameter and 1mm3 in volume). The wall was constructed of the four typical layers of the tubular organ, that are tunica mucosa, submucosa, tunica muscularisand tunica serosa. The average thickness of each tunicawas 3240 mm, 14280 mm, 960 µm and 120 µm, respectively. The Gizzard was rounded sac surrounded by fatty tissue. Noticeably, it lack the smooth muscles fibers which are usually found in the developing gizzard and absence of the keratinoid lining of the mucosal surface. The mean length was 24.34 mm, 12.7 mm in diameter and 3 mm3 in volume.Similarly to the proventriculus, the gizzard’s wall was constructed of the same four tunics that are tunica mucosa, submucosa, tunica muscularisand tunica serosa. The average thicknesses of these tunicae are 1560 mm, 1680 mm, 3240 µm and 120 µm, respectively.