The Association Between Neospora caninum Serological Status and Culling in Ontario Holsteins
Keywords:Neospora caninum, time until culling, culling risk, parasite, abortion
Neospora caninum is a protozoan parasite that is an important cause of abortion in cattle. To determine the economic impact of N. caninum on the dairy industry it is necessary to consider both the direct effect of infection, such as abortion, and potential indirect effects such as altered milk production, reproductive performance and culling. One study involving a large California dairy herd showed that seropositive first lactation cows are at greater risk of being culled than seronegative first lactation cows. However, it is unclear whether this increased risk of culling applies to all parity groups and all dairy herds with seropositive animals. The objective of the present study was to determine if N. caninum serological status in Ontario Holsteins is associated with time until culling and risk of being culled.