Two hundred and four cases of pre-parturient cervico-vaginal prolapse
(CVP) were examined in general practice over three years. An overal incidence
of 1.34% was found with some annual variation within flocks which was most evi¬
dent in upland or hill flocks. There was no true breed disposition but the Kerry,
Llyn, Suffolk and Texel breeds (and their crosses) were slightly overrepresented.
Affected ewes were of all ages and body conditions. Exercise, weather and to¬
pography did not affect the incidence or the severity.
Most cases (80%) occurred in the last 7 days of gestation and overall ewe
mortality was found to be 24% of affected ewes. The progeny of ewes affected
by CVP showed a high incidence of CVP (19%).
While affected ewes carried significantly more lambs than control ewes
(2.4 lambs/ewe respectively) the number of lambs carried did not affect the
severity. Ewes affected by the more severe forms of CVP carried heavier lambs
than either the control ewes or the ewes affected by the milder forms of CVP.
Lamb survival was worse amongst the more severely affected ewes.
Tenesmus and rectal prolapse were often encountered. The relief of
tenesmus was an important part of effective therapy. Post-mortem examina¬
tion showed no ewe to have a ruptured bladder but vaginal rupture, which carried
a poor prognosis for both ewes and lambs, was a complication of CVP in 13 cases.
Eleven treatment methods were compared and none was found to give
better lamb or ewe survival than the others except elective caesarian section
which improved ewe survival at the expense of lamb survival. Delayed caesarian
section resulted in an improved lamb survival but a reduced ewe survival. Ewes
subjected to elective caesarian section showed a reduced conception rate at the
next breeding season.
Inadequate cervical dilation ( ringwombi) was more common in affected
ewes than in controls (17% and 0% respectively) but there was no increase in the
proportion of ewes which suffered from post-parturient uterine prolapse. Post¬
partum recurrence of CVP occurred in 2% of cases.
Affected ewes showed a neutrophilia with left-shift and an elevated
hydroxybutyrate concentration when compared to control ewes. Serum calcium and
inorganic pnosphate were reduced in proportion to the severity of CVP. Blood
urea was frequently elevated and 80% of ewes with urea concentrations above
20 mmol/1 died.
Plasma progesterone levels were higher than in control animals but oestro¬
gen concentrations were lower. The possibility of an hormonal aetiology related
to fecundity, environment, management and anatomy is not discounted.