Experimental material consisted of data concerning the course of calving in 1 094 Jersey cows kept in the years 1995-2001 at the Iwno Stud Farm. The percentage of difficult calvings, those assisted by a veterinary surgeon, and those using cesarean section was 9.68%. While analyzing the course of calving in terms of the division into primiparous and multiparous cows it was shown that difficult parturitions were twice as common in the group of primiparous cows than in the group of multiparous cows. A significantly higher percentage of animals in satisfactory condition was observed among primiparous cows and cows calving in winter and spring. No significant problems were observed with the departure of placenta, although it was found that this disorder was observed twice as often in multiparous cows and twice less often in cows calving in spring. Male calves were the cause of a slightly bigger number of difficult parturitions and all the cases of calving through cesarean section.

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