Coelomitis in Birds

INTRODUCTION

Inflammatory processes within the coelom can be seen secondary to a number of pathologic processes. Among the most common causes, diseases of the reproductive tract, “yolk coelomitis” is one of the more prevalent seen in clinical practice.

ANATOMY

The female reproductive tract consists of the left ovary and the left oviduct in most birds, and lies predominately within the coelomic cavity. 1 The left and right ovary and oviducts develop embryologically as paired structures, but, after hatching, the right ovary and oviduct degenerate. The left ovary is located in the coelomic cavity cranial to the left kidney and adjacent to the adrenal gland. The ovary is attached to the dorsal body wall by the mesovarian ligament, which can have considerably large blood vessels during an active breeding cycle. The ovarian arterial blood supply is usually from the ovario-oviductal branch of the left cranial renal artery, which comes from the descending aorta between the cranial mesenteric artery and the external iliac artery. The venous drainage is via two ovarian veins directly into the vena cava.

Ovarian developmental activity stages noted in the mature hen include: 1) Prenuptial acceleration - the enlargement of the ovarian follicles, 2) Culmination - Ovulation and oviposition, and 3) Refractory period - ovarian follicles reduce in size. It is predominately during the ovulation component of this cycle and less frequently during the ovipositional compoents that yolk coelomitis can be initiated. The left oviduct is attached to the dorsal body wall by the mesovarian ligament. Glandular development within the oviduct results in a thickening of its walls which differentiate it into five functional regions associated with egg formation. These portions are termed the infundibulum, magnum, isthmus, uterus and vagina. […]