Reproduction in Domestic Animals

242 Z RothEvaporative cooling systems used to maintain normothermiain high-lactating cows are likely to remainobligatory in dairy management during the hot season.However, since they only partially restore normalfertility, there is a compelling need for additionalapproaches. Beneficial strategies might involve hormonaltreatment to enhance the removal of impairedfollicles, for example: synchronization of recurringfollicular waves with the use of GnRH and PGF2a, orstimulation of follicular growth with brief treatments ofbST or small doses of FSH. More precise treatmentsdesigned to mitigate the deleterious effect on theendocrine milieu and to increase post-inseminationplasma progesterone should be further examined. Otherstrategies, such as timed embryo transfer, have beenmoderately successful. Therefore, optimizing the proceduresfor cryopreservation might allow producingembryos during the cool months of the year, when theoocytes are not subjected to heat damage. 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