Ovarian Histopathology of Bitches Immunized With Porcine Zonae Pellucidae

Abstract

The ovarian histopathology of bitches immunized with crude (cPZP) or partially purified (pPZP) porcine zona pellucida proteins was examined in order to determine the cause of abnormal estrous cycles. The majority of immunized bitches had ovarian cytes. Those immunized with cPZP had follicular cysts lined with a thin layer of granulosa cells, while in those immunized with pPZP, the cysts were lined by a basement membrane with a clump of luteinized cells. In two bitches immunized with cPZP, oocytes were present only in primordial follicles. Similar abnormalities were not found in a bitch immunized with human serum albumin or in 12 untreated bitches. Oocytes flushed from the oviducts of mated, immunized bitches were degenerating, which may have been a primary cause of infertility in such bitches. Ovaries studied 2-6 weeks after immunization showed no loss of gap junctional communication between oocytes and granulosa cells, nor was any inflammatory reaction seen. IgG was bound to the zona as revealed by fluoresceinated protein A staining of frozen sections of those ovaries. Abnormal estrous cycles in PZP-immunized bitches appear to result from follicular dysgenesis or cyst formation, but the etiology of these conditions is unresolved.

Porcine Zona Pellucida Immunocontraception: Long-Term Health Effects on White-Tailed Deer

“…It has (Miller et al 1999). In this study, we assessed the been suggested that PZP immunization may cause effects of repeated PZP immunization on the ovarian dysgenesis (Mahi-Brown et al 1988, Dun-health of female deer using a 22-test blood serum bar 1989, Tung et al 1996) and loss of primordial profile for treated and control animals over a 4-follicles. Kirkpatrick et al (1992) found that horses year period.…”

Contraceptive potential of porcine and feline zona pellucida A, B and C subunits in domestic cats

“…Therefore, fertility was not impeded by ZP vaccination using this protocol. Several ZP immunization regimes have been shown to affect ovary structure and function, which may or may not manifest as infertility (Mahi-Brown et al 1988, Bagavant et al 1999. It has been reported that ovarian damage is associated with CD4 C T-cell epitopes on the immunizing antigen (Lou et al 1995).…”

Does contraceptive treatment in wildlife result in side effects? A review of quantitative and anecdotal evidence

“…Most changes that occurred to the reproductive tract were changes to follicle number, weight and size with the use of GNRH formulations (McNeilly & Fraser 1987, D'Occhio & Kinder 1995, Gong et al 1995, Maclellan et al 1997) and PZP Side effects of contraceptive treatment treatment (Dunbar et al 1989, Kirkpatrick et al 1992, Kitchener et al 2002, Curtis et al 2007). However, more serious side effects have been reported including increased inflammation of the uterus by intrauterine devices (Daels & Hughes 1995) and alterations to ovarian function, oophoritis and cyst formation with PZP treatment (Mahi-Brown et al 1988, Sehgal et al 1989, Rhim et al 1992, Stoops et al 2006, Curtis et al 2007). In addition, MGA implants can increase mineralization and cystic hyperplasia in felids (Munson et al 2002) and cause endometrial hyperplasia (Sokolowski & VanRavenswaay 1976).…”