The detailed analysis of evolution of Aujeszky’s disease (AD) in the Olsztyn voivodeship in 1987—1991 was performed. In 1987 this situation aggrevated. There were 12 outbreaks of AD, 6 in farms of pigs, 5 in cattle farms and 1 in a fur animal farm. Two main reasons of such situation were underlined, intensive and uncontrolled pig movement without their serological examinations and breeding of pigs and cattle in the same stable. To improve the epizootic situation in November 1987 the obligatory and strict pig movement control measures were introduced. They caused a considerable decrease of new outbreaks in next years. In 1990—1991 losses caused by AD in 2 dogs in individual farmers and in a dog and cat in owners living in towns and in 2 deers were noted.
Бактериологическим исследованиям подвергли 7243 птиц, павших на территории Ольштынского воеводства в 1985—1987 гг. Эти птицы происходили из обобщественных и частных ферм. Изолировали 1431 штамм из рода Salmonella (1041 от индеек, 327 от кур, 36 от уток, 27 от гусей). Нежгутикованные штаммы составляли 1,8%, жгутикованаые — 98,2%. В очередаые годы анализируемого периода отметилось незначительное понижение инфекций этим микроорганизмом, так как в 1985 г. отметили его у 22,0%, в 1986 г. у 19,54%, а в 1987 г. — у 18,2% птиц, исследуемых бактериологически. Изолированные штаммы Salmonella принадлежали к 17 серотипам. Чаще всего появлялись серотипы: S. typhimurium (36,15%), S. saint-paul (20,52%), S. enteritidis (18,62%), S. derby (6,22%).
The first case of Aujeszky’s disease in cattle was found in an individual farm in 1980, and the next ones in large scale breedings. Since 1985 the number of outbreaks showed an increased tendency. Eight outbreaks of the disease was noted in four farms with one or two recurrences in three of them between 1985—1987. The total number of outbreaks was 11 between 1980—1991. Sick or latently infected pigs were the source of the disease. It was confirmed by serological examinations of pigs kept in close contact with cattle. The disease occurred eight times in the period between November and April indicating to its seasonal appearance. Sensitiveness of cattle to infection was high independently on the age, sex and breed. The shorter incubation period and more acute course of the disease was observed in calves than in adult animals. The morbidity rate did not exceed 30—37% though every case was fatal within 24 hours since the first clinical signs. Cerebral signs (excitement), significant pruritus of the head and neck, anorexia, salivation, meteorism, dyspnoe, sweating, mooings and paresis and paralysis before death were observed. Gross lesions were poorly marked, except for local skin lesions. Histopathologically non purulent lymphocytar meningoencephalitis was predominant. From the brain of dead animals Aujeszky’s disease virus was isolated, however, serological test performed in sick or healthy animals were negative.
Quantitative and structural changes in firms during 1993-1996 period in the communities of the Olsztyn province were analysed. The quiekest growth in the number of firms was observed in the communities of average size. The number of inhabitants per one firm in communities of different sizes was levelled during the years analysed, on average it decreased more than twice andin 1996 amounted to 35.4 inhabitants per one firm. Moreover, the number of enterprises in one comunity increased from 1.8 to 4.0. The dynamic of growth in the number of firms decreased, what clearly means a change in organisation structure.