Prosztaglandin kezelés hatása a sárgatestre, a plasma progeszteron koncentrációra és a graaf-féle tüszöre

The results of three different prostaglandin treatment protocols are summarized in our summary: In the first experiment the effects of different doses (0 mg, 25 mg vs 35 mg) of prostaglandin treatments from the day of treatment (Day 0) were examined. The percentage changes relative to the corpus luteum area decreased, and the percentage changes relative to the largest follicle area increased faster, and even the oestrus started sonner in cocas treated with 35 mg PGF2a than in those treated with 25 mg PGF2a. However, these differences between groups were not statistically significant. At the same lime, the decrease in the percentage changes relative to the area of corpora lutea and to the concentrations of P4 was statistically significant in both groups. In the second experiment treatment of dairy cows with 2 luteolytic dosages of PGF2a or its synthetic analogue at an 8-h interval resulted in more cows (non-significantly) (18 vs. 21) being observed in oestrus within 5 d after treatment and having significantly higher conception rate (27,8% vs. 66,6%) than with 1 treatment. Further studies in progress should confirm the benefit of 2 prostaglandin treatments in a larger scale. At the same lime, the type and the number of prostaglandin treatments had no effect on the incidence of ovulations alter oestrus, the number of ovulations without oestrous signs, the number of cows without oestrus and ovulation, and the average lime from treatment to oestrus. In the third experiment the lime of ovulation was examined alter detected oestrus and A.I. (Day 0) in prostaglandin treated and non-treated dairy cows. Large variations in the area of the CL were detected in the prostaglandin treated and untreated cows. The areas of the largest follicles in treated cows were somewhat smaller during the experiment, than those in untreated cows however those differences between the groups and within the groups were not statistically significant. The area of the largest follicle in cows with no ovulation also did not differ significantly. Some of the cows (n=7) in treated and non-treated groups did not ovulate at all during the experiment. The mean area of the ovulatory follicle on the day before ovulation was somewhat greater but not significantly, if ovulation occurred later regarding to AI, The overall conception rate was > 50% in both groups, but when the cows ovulated too early or too late in relation to the lime of AI the conception rate was significantly louver, therefore determination of the optimal lime for AI is of great practical importance. If ovulation does not occur within two days alter AI second AI may be recommended. Further studies are needed to evaluate the benefit of the second AI