Incidence, economic effects, and control of Haemophilus pleuropneumoniae infections in pigs.

This thesis synopsis reports the results of investigations on: the incidence of clinical and subclinical H. pleuropneumoniae infections on pig farms in North Brabant; the economic loss on fattening farms; the effect of husbandry; the possibility of eradicating H. pleuropneumoniae on infected breeding farms on the basis of serological testing; the possibility of control on fattening farms by means of vaccination. The principal findings were as follows: Clinical and subclinical H. pleuropneumoniae infections are widespread on pig farms in North Brabant: The greatest economic loss was due to mortality and veterinary fees; the daily weight again was not found to be affected. The effect of husbandry. Less mortality occurred: on farms where the animals were not shifted during the fattening period; in compartments where the all-in all-out method was systematically used; in compartments with thermostatically controlled warming of the incoming air; in compartments meeting all standards of a good housing climate. Various sanitation measures on infected breeding farms were not successful. Only one experimental vaccine afforded good protection, but because of a high percentage of injection abscesses this vaccine was unsuitable for use in practice.