Comparative cervical cytology and conception rate in postpartum dairy cows

During the early postpartum period, multiple bacterial species invade the uterus of cows. Phagocytosis by polymorphonuclear cells is a primary mechanism involved in the elimination of bacteria and improvement of conception rate. Therefore, a relationship could exist between endometrial cytology and conception rate of postpartum dairy cows. In this study 50 postpartum healthy Holstein Frisian dairy cows were selected. They had a normal parturition history and had no mucopurulent discharge from vulva or abnormality in rectal palpation. Cervical mucosal discharge was collected from all cows on days 25 to 30 and 55 to 60 postpartum. Blood progesterone levels were determined in all cows by radioimmunoassay (RIA). Differential cellular counts were carried out from a Giemsa-stained smear of the mucosa. Data were analyzed by Independent T test, one-way ANOVA, and Duncan’s multiple range tests. There was no significant difference between cell percentages at different times or in number of postpartum artificial inseminations (P≥0.05). However, when cows were divided into two groups to progesterone above 1 ng/mL and below 1 ng/mL, there were significant differences (P<0.05) between neutrophil percentages at different times after parturition and artificial insemination number (1 and 2 or 3). The result of this study showed that cytological evaluation of cervical smear is helpful for diagnosis and treatment of subclinical endometritis and prognosis of postpartum fertility.