Odde K G
Dept. of Anim. Sci., Colorado State University, Fort Collins 80523.
J Anim Sci. 1990 Mar;68(3):817-30. doi: 10.2527/1990.683817x.
Estrus has been synchronized in cattle with progestogens, prostaglandins (prostaglandin F2 alpha and its analogues), progestogen-estrogen combinations and progestogen-prostaglandin combinations. Progestogens administered for 14 to 20 d are effective in synchronizing estrus; however, fertility at the synchronized estrus is subnormal. Duration of progestogen treatment can be reduced by combining it with an estrogen. Syncro-Mate B is a progestogen-estrogen combination that results in a tightly synchronized estrous response. Prostaglandins can be used in double- or single-injection programs. Fertility of the estrus after prostaglandin treatment is similar to that of controls. Estrus also has been synchronized effectively by combining a 5- to 9-d progestogen treatment with prostaglandin at or near the end of treatment. When prostaglandin is used alone, cattle in the late stages of the luteal phase (d 11 to 15 of the estrous cycle) at the time of prostaglandin injection have a higher estrous response and may be more fertile than those injected with prostaglandin in the early part (d 6 to 9) of the luteal phase. More recently, a 14-d progestogen treatment has been combined with a prostaglandin injection given 16 to 18 d after progestogen withdrawal. This system places cattle in the late luteal phase of the estrous cycle at the time of prostaglandin injection and has resulted in an estrus with greater fertility than that immediately following progestogen treatment.
在牛身上，已使用孕激素、前列腺素（前列腺素F2α及其类似物）、孕激素 - 雌激素组合以及孕激素 - 前列腺素组合来同步发情。给予14至20天的孕激素可有效同步发情；然而，同步发情时的受胎率低于正常水平。将孕激素与雌激素联合使用可缩短孕激素治疗的持续时间。Syncro - Mate B是一种孕激素 - 雌激素组合，可产生紧密同步的发情反应。前列腺素可用于双注射或单注射方案。前列腺素治疗后的发情受胎率与对照组相似。通过在治疗结束时或接近结束时将5至9天的孕激素治疗与前列腺素联合使用，也可有效同步发情。当单独使用前列腺素时，在注射前列腺素时处于黄体期后期（发情周期的第11至15天）的牛比在黄体期早期（第6至9天）注射前列腺素的牛有更高的发情反应，且可能更易受孕。最近，14天的孕激素治疗已与在停用孕激素16至18天后给予的前列腺素注射相结合。该系统使牛在注射前列腺素时处于发情周期的黄体期后期，并且所产生的发情期受胎率高于孕激素治疗后立即出现的发情期。
