INVESTIGATIONS ON PIGLETS AND STORE PIGS IN HIGH-CONCENTRATION STOCK TO ELUCITADE COLONIZATION OF NASAL-MUCOSA BY BACTERIAL SPECIES OF RELEVANCE TO RESPIRATORY-TRACT - BORDETELLA-BRONCHISEPTICA, PASTEURELLA-MULTOCIDA AND HAEMOPHILUS-PARASUIS

Studies were conducted into the dynamics of colonisation of nasal muco sa of growing pigs by three bacterial species of relevance to the resp iratory tract, H. parasuis, B. bronchiseptica and P. multocida. Testin g was based on 1,31 1 nasal swab samples taken from five pig herds on high-density units. Isolation was possible of the following strains: 4 11 H. parasuis, 157 B. bronchiseptica and 103 P. multocida, among them 26 toxiferous strains. H. parasuis was recordable from nasal mucosa o f piglets as of the first week of age. The polypepitde Type 1, charact erised as apathogenic, accounted for 85.2 percent of all isolates. LPS Type 2 was the most common LPS type in all isolates and accounted for 60.9 percent. P. multocida and B. bronchiseptica were recordable as o f the first week of age, with their trend rising up to the point of we aning. Intensity of recordability were affected by both stock size and keeping conditions.