Inflammatory response and microflora in the bitch’s uterus after artificial insemination

Abstract

The present study aimed to obtain information about the uterine inflammatory reaction (number of polymorphonuclear neutrophilic granulocytes-PMNs)  in bitches after artificial insemination (AI), as well as to describe the endometrium of oestrus bitches and identify the uterine microflora present during that phase. The bitches were divided in three experimental groups according to the following treatments:  insemination with semen with extender (n=6), insemination with fresh semen ( n=6)  and no inseminated (n=6). The percentage of PMNs on the endometrial surface and within histological sections were evaluated together with the presence of aerobic bacteria in the uterine lume . For  endometrial cytology and histology, there was no significative difference on the number of inflammatory cells between bitches not inseminated and those inseminated with fresh semen; however in both groups the number of inflammatory cells it was smaller than in the inseminated with semen plus extender (p<0,05). The cells identified in the endometrial cytology were endometrial epithelial cells, leucocytes and red blood cells. Histology showed congestion of the conective tissue, proliferation of endometrial glands, inflammatory cells, fibroblasts and red blood cells. The microbiological exam  showed the presence of  Staphyloccocus sp and Proteus sp.  Although we postulate that the most used extender for semen freezing in dogs is a potent inducer of uterine inflammation; positive uterine cultures may be obtained during oestrus without the presence of endometrial inflammation or uterine infection.