EFFECT OF DISEASES, PRODUCTION, AND SEASON ON TRAUMATIC RETICULOPERITONITIS AND RUMINAL ACIDOSIS IN DAIRY-CATTLE

Logistic regression was used to investigate the effects of host characteristics, production, and 23 veterinary diagnoses on the risks of two reticuloruminal disorders, ruminal acidosis and traumatic reticuloperitonitis among 61,124 Finnish Ayrshire cows. Lactational incidence risks were .3% for ruminal acidosis and .6% for traumatic reticuloperitonitis. The relative risk of ruminal acidosis was not related to parity, whereas the risk of traumatic reticuloperitonitis decreased with increasing parity. The risk of traumatic reticuloperitonitis was not related to milk yield of individual affected cows in their current or previous lactation (305-d, 4% FCM), whereas the risk of ruminal acidosis increased with current milk yield. Ketosis, early metritis, nonparturient paresis, and acute and chronic mastitis were risk factors for both reticuloruminal disorders. Parturient paresis was a risk factor for ruminal acidosis. Foot and leg problems were risk factors for traumatic reticuloperitonitis. Herd milk yield in the current or previous lactations was not a risk factor for either disorder nor were the two disorders risk factors for each other. Ruminal acidosis, but not traumatic reticuloperitonitis, had significant seasonal variation with the risk being least in summer. The low risk of ruminal acidosis in summer was not due to seasonality of calving. © 1990, American Dairy Science Association. All rights reserved.