Incidence. Dystocia is defined generally to
include any calving in which assistance is
required. It has been scored quantitatively in
various ways. Calving difficulty or dystocia
averages about 5.8%, ranging from .9 to 13.7%
in eight studies comprising 218 herds (predominantly
Holstein) and 40,828 calvings
(Table 2).
Predisposing Factors. Much has been written
about dystocia in cattle, including several
reviews concerning its economic significance in
terms of calf loss and subsequently impaired
reproductive performance (42, 65, 72). The
etiology of dystocia is not completely clear, but
it is primarily a function of the size of the calf