Zmiany morfologiczne jajnika i macicy po antykoncepcji estrogenowej u suk

In the present study we have evaluated the effect of estrogen contraception on ovarian and uterine morphology in healthy bitches. 30 crossbreed bitches with physiological estrous cycle (1-3 y; 10-14 kg) were divided into control (n = 6) and two experimental groups of 12 bitches treated twice with different doses of estradiol benzoate (EB). The first group received 10 µg EB/kg BW (Mesalin, Intervet), and the second 100 µg EB/kg BW (Oestradiolum benzoicum, Polfa), given i.m. on day 3 and 5 after the first acceptance of a male. The ovaries and uteri were collected 14 or 28 days from the first EB injection. The histopathological evaluation and histomorphometric measurements were performed using computer assisted analysis. There was no significant effect of estrogen treatment on ovarian activities at either dose. The uteri of bitches from the control group have shown progressive regression of all endometrial elements typical for the middle part of the luteal phase of the estrous cycle. The low dose EB treatment caused glandular hyperplasia characteristic for early stages of cystic formation. The higher dose resulted in total inhibition of cell proliferation, stimulation of glandular hyperplastic (complex) changes and increased thickness of the uterine wall. At the latter time the cystic changes within the glandular part may cause endometritis or even pyometra. The results obtained indicate the need for clinical follow up of bitches treated with estrogens.