Aspects épizootiologiques des affections respiratoires porcines qui sévirent au Québec, de septembre 1980 à février 1981.

EPIZOOTIOLOGICAL ASPECTS OF PORCINE RESPIRATORY DISEASES WHICH WERE ENCOUNTERED IN QUEBEC FROM SEPTEMBER 1980 UNTIL FEBRUARY 1981: In the spring of 1981, a questionnaire was mailed to pig farmers of Quebec, in order to determine the epizootiological factors susceptible to account for the deaths which had occurred during the period extending from September 1980 until February 1981. The mortality rate was estimated at 4.5% for that period. It proved to be higher on the farms where hogs were fattened only (5.9%), compared to those where they were raised and fattened (3.4%) and for those where the hogs were owned (6.8%) compared to those where they were fattened by contract (4.3%). During that six month period, severe mortality problems (>/= 4%) were experienced by approximately 32% of the hog producers in Quebec, mainly by those who were fattening hogs. The mortality rate was found to be proportional to the size of the herds; it proved to be definitely higher when the pigs had been bought at auction sales or from livestock dealers and even higher when the pigs had been simultaneously obtained from both sources. The results of this investigation and the importance of some epizootiological factors are discussed. The economical loss for the Province was estimated at $15 120 000 for the 126 000 pigs which died during that six month period.