Prevalence, Risk Factors and Differential Diagnosis of Cystic Ovarian Degeneration in Crossbred Cows

Abstract

The present study was conducted under field conditions on >90 days postpartum HF crossbred cows with cystic ovaries (n = 58). The
diagnosis was confirmed by history and trans-rectal palpation and ultrasonographic examinations twice at weekly interval using 5.0–7.5
MHz frequency probe and was later authenticated with plasma progesterone assay and treatment response. The animals with follicular
cysts were randomly treated with either conventional ovsynch or ovsynch + CIDR protocol with fixed time AI (n = 10 each), and those
with luteal cysts with either double PG injections 11 days apart or modified Ovsynch protocol (n = 16 each). Among 58 cystic cows,
the highest incidence (62.07 %) of the ovarian cyst was recorded in the age group of 5–7 years followed by above 7 years (36.21%) and
3–5 years (2.00%). The incidence was highest among cows of 3rd or more parity (70.69%) followed by 2nd parity (29.31%), and no case
was seen in primiparous cows. Of the total 36.21% were follicular type cyst and 63.79% luteal type cysts. The right ovary had a high
incidence of the cyst (51.72%) followed by the left ovary (36.21%), and bilateral (12.07%). Based on rectal palpation, the cystic ovary was
classified to have follicular cyst in 36.21% (21/58) cases and luteal cysts in 63.79% (37/58). Ultrasound examination showed follicular
and luteal cysts as 27.59% and 72.41%, whereas plasma P4 (</> 1 ng/mL) analysis revealed this as 20.69% and 79.31%, respectively.
The clinical diagnosis became more accurate with a combination of per rectal palpation and USG and was further improved by plasma
progesterone assay. The mean diameters and a wall thickness of cysts varied highly significantly (p <0.01) between groups/protocols.
The conception rates at induced estrus with FTAI in cows under ovsynch, ovsynch + CIDR, modified ovsynch and double PG protocols
were 50.00, 40.00, 50.00 and 43.75 percent, respectively. It is thus concluded that in crossbred cows luteal cysts are more common than
follicular cysts, particularly in prime aged animals of 3rd or 4th parity with more of left ovarian involvement. The differentiation of cyst
type is best achieved with the combined use of USG and/or plasma progesterone assay with rectal palpation, and that ovsynch protocol
appeared promising for the treatment of follicular cysts and Modified Ovsynch for luteal cysts.