The Main Causes of Calf Mortality in Dairy Farms in Poland

Calf mortality is one of important problems of calf rearing in dairy farms worldwide. Besides, several noninfectious factors, such as management around birth, colostrum management, calf housing, feeding system, hygiene and pathogens, play an important role in calf rearing. The aim of the study was to show the most common causes of mortality of calves up to 90 d of their lives. Some data are available concering calf rearing management on small and medium size dairy farm typical for Polish regions. The research was conducted in seven selected herds of Polish Holstein-Friesian cows located in South of Poland. Data on calves mortality covered the period of three years from 2004 to 2007 and were collected using medical documentation and medical inquire in the farms. All evidence was enrolled untill three months of age of calves. There were 1,800 calves tested. The influence of such factors as maintaining system (free stalls barn and stalls barns), feeding systems and herd size on falls of calves was examined. Overall, mortality throughout the three months of study period was diarrhea, which increased the risk of death among calves younger than 90 d of age. Also, respiratory system disorders were the common cause of loss of calves. The calf mortality rate during 90 d in all herds registered in free stall barns was 61% and in stalls barns was only 29%. Effect of pneumonia in free stall barns was 18% and in stall barns was 29%. In all groups, calf mortality rates increased with increasing herd size.