We investigated the
therapeutic effects of a
progesterone releasing intravaginal device (
PRID) on cystic
ovarian disease (COD) and reproduction performance of cows. The possible influence of
PRID on metabolic and/or health status was also examined. A total of 40 Holstein-Friesian cattle, with ovarian cystic structures, > or =2.5 cm in diameter, persisting for more than 7-14 days, without a corpus luteum (CL) were used for the study.
PRID or
placebos were inserted into the vagina for 12 days. Five animals lost the intravaginal device before removal and one was culled. Based on plasma
progesterone concentration on the day of treatment, 20 (17
PRID and 3
placebos) of the remaining 34 cows had
follicular cysts (
progesterone < or =1 ng/ml) and 14 (10
PRID and 4
placebos) had luteal
cysts (
progesterone >1 ng/m l). Fourteen (82%) of the
PRID-treated follicular cystic cows responded with formation of a CL within 14 days
after treatment, and an overall conception rate of 53.8%. Likewise, 70% of the treated luteal cystic cows responded with CL formation and 71.4% conception rate. No significant differences were observed in hematocrit (Ht), white blood cell count and serum levels of
glucose, blood urea nitrogen,
aspartate aminotransferase, and
alanine aminotransferase, between the day of
PRID insertion and removal, in animals with follicular and luteal
cysts.
PRID treatment resulted in ovulation 2-4 days later and formation of a CL in cows that recovered.