Human chorionic gonadotropin manufacturer
1. Gonadotropin-releasing hormone (GnRH)
The use of GnRH and its analogues can induce oestrus ovulation in dogs, but
the effect is not consistent. Some studies have shown that GnRH injection is
only effective when follicles on the ovaries have developed to a certain extent.
GnRH does not increase the number of growing follicles, but only promotes the
ovulation of mature follicles.
Gonadotropin has been widely used to induce estrus in dogs. These hormones
are effective in stimulating follicle growth and ovulation in dogs. Due to the
short half-life and high price of FSH and LH, placental gonadotropin PMSG and
human chorionic gonadotropin HCG are commonly used in production practice.
Analysis of the reasons for the different effects after use suggests that,
firstly, it may be due to the different number of developmental follicles that
can respond to hormone treatment; secondly, it may be related to the different
response of the tested dogs to hormone; thirdly, it may be related to the
different response of the tested dogs to hormone treatment. And finally, of
course, it may have something to do with the quality of the hormones used. In
addition, PMSG combined with HCG can be used to induce estrus in female dogs,
especially those who have been in heat. However, the rate of oestrus induction
and ovulation was only 20%, far lower than that of natural oestrus. This may be
due to the use of exogenous hormones to shorten the normal maturation of
follicles, resulting in follicle growth and development of insufficient and
affected the quality of gametes. In addition, most of the females treated with
the combination of the two have abnormal lutein P4 level and insufficient lutein
function, thus unable to maintain the normal pregnancy.