Clinical disorders in holstein cows: Incidence and associations among lactational risk factors

Abstract

A retrospective study of possible associations among lactational incidence risks of clinical health disorders in the current lactation in dairy cows from selected Holstein herds in Lower Saxony (Germany) was carried out on the basis of data obtained from herd health and production management programme. The associations were studied using the χ2 test. Data on 2197 lactations of 1074 cows originated from 10 commercial herds participating for 2 to 5 years (from 1990 to 1996) in the programme. The herds had 48 dairy cows on average, milk yield of 8137 kg and mean parity of 2.9. We tested eight clinically identifiable health disorder complexes reaching the following lactational incidence risks: parturient paresis (7.0%), retained placenta (8.9%), displaced abomasum (1.1%), metritis (23.6%), clinical ketosis (1.7%), clinical mastitis (21.6%), ovarian cysts (11.7%) and claw diseases (19.5%). Dairy cows suffering from parturient paresis were at 1.4 (1.1-1.7) and 1.7 (1.3-2.2) significantly (P ≤ 0.05) greater risk of suffering from metritis and clinical mastitis, respectively, in the current lactation. Retained placenta was significantly (P ≤ 0.05) associated with 3.0 (2.6-3.5) times higher lactational incidence risk of metritis, which was a significant (P ≤ 0.05) risk factor for ovarian cysts (odds ratio 1.4; 95% confidence interval 1.1-1.8). These associations provide further support to the notion that health problems in dairy cows tend to occur as a complex, especially in the postpartum period.