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Simulation study of the mechanisms underlying outbreaks of clinical disease caused by Actinobacillus pleuropneumoniae in finishing pigs


, : Simulation study of the mechanisms underlying outbreaks of clinical disease caused by Actinobacillus pleuropneumoniae in finishing pigs. Veterinary Journal 202(1): 99-105

Actinobacillus pleuropneumoniae is a major cause of respiratory disease in pigs. Many farms are endemically infected without apparent disease, but occasionally severe outbreaks of pleuropneumonia occur. To prevent and control these outbreaks without antibiotics, the underlying mechanisms of these outbreaks need to be understood. Outbreaks are probably initiated by a trigger (common risk factor) changing the host-pathogen interaction, but it is unclear whether this trigger causes all cases directly (trigger mechanism), or whether the first case starts a transmission chain inducing disease in the infected contacts (transmission mechanism). The aim of this study was to identify conditions under which these mechanisms could cause A. pleuropneumoniae outbreaks, and to assess means for prevention and control. Outbreaks were first characterised by data from a literature review, defining an average outbreak at 12 weeks of age, affecting 50% of animals within 4 days. Simple mathematical models describing the two mechanisms can reproduce average outbreaks, with two observations supporting the trigger mechanism: (1) disease should be transmitted 50 times faster than supported by literature if there is a transmission chain; and (2) the trigger mechanism is consistent with the absence of reported outbreaks in young pigs as they have not yet been colonised by the bacterium. In conclusion, outbreaks of A. pleuropneumoniae on endemic farms are most likely caused by a trigger inducing pneumonia in already infected pigs, but more evidence is needed to identify optimum preventive interventions.

US$19.90

PMID: 25155305

DOI: 10.1016/j.tvjl.2014.06.015


Other references

Stomskaya, T.P.; Grigorian, I.A.; Ossovskaya, V.S.; Rybalkina, E.Y.; Chumakov, P.M.; Kopnin, B.P., 1995: Cell-specific effects of RAS oncogene and protein kinase C agonist TPA on P-glycoprotein function. We compared the influence of exogenous N-ras oncogene and treatment with PKC agonist 12-O-tetradecanoylphorbol-13-acetate (TPA) on P-glycoprotein (Pgp) function in various human, rat and dog cell lines. Two approaches were used: (a) flow cytometry...

Hoke G.D.Jr; Tawes J.W.IIi; Llewellyn G.C., 1976: Fertilization and pathology in rats intubated with afla toxin b 1. Virginia Journal of Science 27(2): 45

Gorman J.J.; Castaldi P.A., 1977: Characterization of multiple forms of human thrombin. Thrombosis & Haemostasis 38(1): 147

Johannsson, J.H.llur.; Gudjonsdottir, B., 1995: Atlas of breeding birds in Steingrimsfjordur and vicinity, NW-Iceland a survey 1987-1994 Varpfuglar i Steingrimsfirdi og nagrenni Konnun 1987-1994. Fjolrit Natturufraedistofnunar. Desember; 28: 1-76

Izakov, F.Y.; Ryss, A.M.; Malkiel' , G.I., 1989: Smooth regulation of calorifier output. A system of pipe and calorifier heaters designed for heating a 1500 msuperscript 2 greenhouse (hangar-type) with +or-1 degrees C accuracy is described. A specially designed instrument automatically regulates the speed of calorifier fans, taking in...

Doğan, M.Cem.; Haytac, M.Cenk.; Ozali, O.; Seydaoğlu, G.; Yoldas, O.; Oztunc, H., 2006: The oral health status of street children in Adana, Turkey. To determine the oral health status of street children and compare the results with a group of non-working children in Adana, Turkey. Street children are generally defined as any boy or girl for whom the street has become his or her habitual abode...

Hoffmeister, H.E., 1969: Clinical course and liver circulation following shunt operations in portal hypertension. Medizinische Klinik 64(50): 2332-2337

Manly, J.J.; Schupf, N.; Stern, Y.; Brickman, A.M.; Tang, M-X.; Mayeux, R., 2011: Telephone-based identification of mild cognitive impairment and dementia in a multicultural cohort. Telephone-based interviews can be used for screening and to obtain key study outcomes when participants in longitudinal studies die or cannot be seen in person, but must be validated among ethnically and educationally diverse people. To determine...

Campbell, J.M., 1982: Barn owl bringing down kestrel. British Birds 75.11: 536

Taksdal, G., 1959: Attack by L. campestris in carrot seed fields leads to reduced germination and yield. The following is based on the author's summary. Lygus campestris (L.) was found injuring the developing seeds of a carrot seed crop in Norway in 1956; other plants were also infested. The umbels were attacked by both nymphs and adults, and de...