Cattle generally ovulate only one oocyte at a time, resulting, normally, in the birth of only one offspring per pregnancy. The reported incidence of twin births in dairy breeds is higher than that in beef breeds and historically ranges from 1.3% for Jerseys through 3.4% for Holsteiiis and up to 8.9% for Brown Swiss. However anecdotal reports of multiple births in dairy cattle would appear to be on the increase with some farms especially affected (Esslemont and Kossaibati, 1996, Kinsel et al, 1998). So it seems likely that the true incidence is higher than the historical figures suggest. The occurrence of triplets and quadruplets in cattle is even rarer with reported incidences of less than .001%.
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