Effect of ovarian hormones on the phagocytic response of ovariectomized mares
Ganjam, V.K.; McLeod, C.; Klesius, P.H.; Washburn, S.M.; Kwapien, R.; Brown, B.; Fazeli, M.H.
Journal of Reproduction and Fertility. Supplement 32: 169-174
1982
ISSN/ISBN: 0449-3087 PMID: 6962850 Document Number: 193979
The reaction between ovarian hormones and experimental uterine infection (Streptococcus zooepidemicus) was investigated in three groups, each containing six ovariectomized mares. Group 1 served as controls ('anoestrus'), Group 2 mares were injected with oestrogen ('oestrus') and Group 3 with progesterone ('dioestrus') over a period of five weeks. All mares received an intrauterine inoculation of the bacteria one week after the start of hormonal treatment, and the results of the challenge were examined by endometrial biopsy and swabs once weekly. At the end of week 1 no bacteria were recovered from the mares in Group 2. Group 1 mares were free from bacteria at the end of week 2 but all Group 3 mares remained infected at least for the total period examined. Streptococcal phagocytosis was quantitated by chemiluminscence. Before the challenge-inoculation, phagocytosis was not significantly different in the three groups of mares. Bacterial cultures were negative for all three groups. However, within 48 h after infection, there was a significant increase in phagocytosis in Group 2 and significant suppression in Group 3 mares. Patterns of streptococcal clearance from the uterus closely paralleled the changes in the magnitude of chemiluminscence response. The results suggest that ovarian hormonal status can modulate the phagocytic response in episodes of streptococcal-induced endometritis in mares.