Placentation is formation of placenta. Placenta is attachment of
fetal membrane with the endometrium of dam to permit the
physiological exchange between dam and fetus. It is required till
term but once the animal delivers the calf then there is no need and
dam have to expel it out otherwise body will take it as foreign.
Most of dairy animals expel the placenta within 8 hours after
delivery of their calf. If placenta is not expelled for 12 hours or
more after parturition, it is indicative of abnormal condition and
called as retention of fetal membranes.
In last 10-15 days of gestation corticosteroid level increases in
blood and more estrogen is producted due to which contractions occur
and sharp edges of cotelydons become flat and detach easily.
Premature delivery or abortion leads to retention because of
If something is wrong with pituitary, there is proliferation of
epithelium in villi and a band like structure forms which interfere
with the detachment of plancentomes.
Lack of Uterine Contractions:
Lack of uterine contractions due to uterine inertia (primary or
secondary), low level of Ca, hormonal deficiency particularly of
estrogen, improper balance of progesterone and estrogen.
Placentitis or Cotyledinitis:
Associated with bacterial, viral, and fungal diseases e.g. Burcella
abortus, tuberculosis, Vibrio fetus, IBR, Staphylococcus aureus, E.
coli, Corynebacterium pyogenes and Pseudomonas, IPV virus and
various mold infections due to aspergilla or mucor
Associated with dystocia, hypocalcaemia, hydropic and other
Severe Deficiency of Selenium, Vitamin A, D, E:
Glutathione peroxidase splits H2O2 whose
integrity requires Se and Vitamin E. If there is deficiency of Se
and vitamin E, this enzyme will not work properly and ultimately
cells will be damaged by H2O2. Vitamin A is
required for maturation of epithelium
Short dry period, transport stress, changes in the locality in
advanced pregnancy, high milk production, parasitic infestations and
other causes of debility and underfed.
Loss of appetite
Decrease in milk production
High rise of temperature
May lead to all symptoms of toxemia
Extreme retention leads to pyometra and septic metritis.