Published in Scientific Works. Series C. Veterinary Medicine, Vol. LXI
Written by Marcel Theodor PARASCHIVESCU, George Florea TOBĂ, Marcel PARASCHIVESCU, Mariana Sandu
Forced increased fertility in cattle can be obtained by multiple ovulation embryo transfer (MOET). This paper presents results of a trial to shorten interval between two pollyovulation treatments to the term determined by the natural estrus shown by donors after the previous embryos’ collection. Pollyovulation was provoked using FSH. Experiment started with 4 Romanian Black and White heifers, 17 month aged, but only two of them answered to the treatment for estrus synchronization. Both these heifers have shown heat in the same day, at 11 days after uterine washing. A total number of 27 yellow bodies were counted (14 units in one heifer and 13 in the other), but only 12 embryos were collected (11 embryos from the first heifer and 1embryo from the second). There is no explanation of the fact. The resulted interval between pollyovulation treatments was 53 days, 7 days less than the 60 days interval recommended by literature. More interesting was the presence of a total 26 atretic follicles in the 4 days (diestrus state) of embryo collection. They must pertain to the first wave of follicles starting maturation after prostaglandin injection given at embryo collection to prevent pregnancy. The fact suggests the possibility to stimulate these waves of follicles to have shorter interval between pollyovulation treatments. It is counted that the interval could be shortened up to 25 days. If that is possible MOET could be applied in heifers to increase selection precision of mother of sire dams by progeny testing them. New idea is to use MOET in dams of known genetic merit to discover better compatibility of parental pairs to obtaining the wanted type of the breed. Experiments are needed also to establish if more frequent uterine washings cause or don’t cause alteration of uterine mucosa functions.
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