[Mortality by crushing in domestic pigs: study of the causes and their relationship to the time and the month of the year in the climatic conditions of Cuba].

In the course of 3 years a complex of 25,000 pigs were investigated once per week for the dead among the 398 sucking piglets, and in the case of losses due to crushing to death the type of lesions and the connection with diseases was investigated. Of the piglets investigated, 88 were crushed to death (21.2%), among them 65 (73.8%) diseased--mainly infected by coli bacilli (60 = 68.2%)--and 23 (5.8%) healthy animals. The losses due to crushing to death were highest in January and differed from all other months of the year (p less than 0.05). Another peak of losses in July was only significant (p less than 0.05) as compared with the values of April and November. January and July also exhibited the highest proportion of coli-infected piglets. The most frequent lesions were edema and cyanosis of the skin, of the mucous membrane, and the hypodermic tissue, haemothorax and haemoperitonaeum, liver cracks, lung cracks, kidney cracks, stomach cracks, large intestine cracks, and multiple fractures of the ribs and of the skull. It is concluded that the losses due to crushing to death can be related to the decrease in vitality of the piglets due to diseases, caused in winter by decreased vitality and in summer by pressure caused by coli infection.