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21.
A focal uterine adenomyosis is described in two bitches. In both cases, the uterus showed knobbly enlargements of 4 to 8 cm in diameter, which resulted in distinct clinical symptoms. Other pathological changes of the uterus were not present. One bitch was presented because of a history of vaginal discharge of several months' duration. Radiographs, as well as ultrasonography, revealed a soft tissue lesion at the cervix. The other bitch showed a marked reduction in its general condition and a sudden onset of a tense abdomen. Radiologically, a lesion of soft tissue opacity was observed in the mid-abdomen and was seen to originate from the left uterine horn during exploratory laparotomy. A torsion of the lesion was present, which explained the clinical signs in this second case.  相似文献   
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Sustainable animal production requires a healthy production system including healthy animals producing wholesome products. Epidemiology as a discipline is concerned with the occurrence of disease or disease indicators in populations as well as with factors influencing disease occurrence. By providing this information, epidemiology contributes significantly to the development and maintenance of healthy livestock. This is illustrated with the example of the enzootic pneumonia (EP) eradication programme of Switzerland. A series of observational studies were conducted in order to obtain the necessary knowledge to implement an area-wide EP eradication programme. The issues of economical eradication strategies at the herd level and the risk of re-infections were addressed. Simulation modelling and economical analysis were also applied. These research projects led to the successful start of a national eradication programme. The example of the EP eradication programme illustrates that applied epidemiological research provides critical information for the planning, implementation and evaluation of disease control programmes and is thus a key tool in developing sustainable animal production.  相似文献   
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Exposure of a group of horses to tetracycline-contaminated feed resulted in acute colitis and subsequent death in one horse and milder diarrhea in 3 others. The most severely affected animal demonstrated clinical and pathological findings typical of colitis X. The other herdmates responded well to administration of zinc bacitracin.  相似文献   
24.
An eight-month-old female rottweiler was presented with a history of intermittent lameness of the right hindlimb of 4 weeks duration. Radiographs showed a fragmentation in two plantar sesamoid bones of the metatarsophalangeal joint. Based on these clinical and radiographic signs sesamoid disease of the 2nd and 7th sesamoid bone in the right hindpaw was diagnosed. The fragmented sesamoids were surgically removed and histologically examined. The treatment was successful and the dog became lamnessfree. Additional radiographs showed fragmentations of sesamoid bones VII of both the forepaws, but they did not cause any lameness.  相似文献   
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The aim of this analysis was to characterise the temporal pattern of infection during the 1997/98 classical swine fever (CSF) epidemic in The Netherlands and hence identify and quantify risk factors for infection in different enterprise types and areas. Survival analysis and Cox proportional hazards regression were used to describe the epidemic. Substantial differences in temporal survival patterns (herd breakdown rate) were found between areas where different control policies operated. Factors with a significant influence on the infection hazard of individual herds included: sow numbers as a percentage of total sows and fatteners (HR = 3.38 for mixed herds (0.1–60% sows) vs. fattening herds (0% sows) and HR = 2.74 for breeding herds (60–100% sows) vs. fattening herds), the number of ‘transport contacts per month’ (>0.3 vs. <0.3; HR = 4.11), pig density (pigs/km2) in the area (HR1000 pigs 1.48) and herd size (HR100 pigs = 1.01).

Pre-emptive slaughter in an area appeared to be associated with lower subsequent disease levels. Higher frequency of transport contacts for welfare slaughter during the epidemic, however, well regulated and controlled, was associated with a substantially higher risk of becoming infected. The positive association of a higher pig density with CSF indicates the potential importance of local spread as a factor in disease transmission and emphasizes that dilution of the pig population can contribute to reduction in CSF occurrence. This analysis suggests however, that if pre-emptive slaughter can promptly be applied effectively in an area after initial diagnosis, pig density is then not a significant factor. Mixed and breeding herds had a higher probability of becoming infected than fattening herds, possibly due to different types and frequencies of inter-herd contacts. These contacts continue to some extent during the epidemic, despite the standstill of animal movements.  相似文献   

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Summary Increasing numbers of human and animal diseases have been shown to be disseminated by micro-organisms in aerial suspension. The viability of such airborne organisms declines progressively as the result of physical and other factors which are summarized in the text. Relative humidity strongly influenced viability in experimental studies, but strain differences also appear to play an important role in certain diseases. Laboratory results were confirmed by observations made in the field on poliomyelitis, smallpox, foot and mouth disease, rinderpest and Newcastle disease; it is probable that Marek's disease, avian infectious bronchitis and numerous other maladies spread in the same manner. Long range dissemination by airstreams may be influenced, to some extent, by the virulence of the causal agent and by the fall-out rate for particles of a size which is optimal for deposition at the predilection site of the specific organism. Furthermore, local geographical and climatic factors may greatly modify distributional patterns of airborne disease during major epidemics or epizootics: specific outbreaks are cited as examples.
Sumario Se ha demostrado que un número criente de enfermedades tanto en el hombre como en los animales son diseminadas por micro-organismos que se encuentran en suspension en el aire. La viabilidad de tales micro-organismos en el aire declina en forma progresiva como resultado de factores fisicos y otros factores sumarizados en el texto. La humedad relativa influencia de manera especial la viabilidad en estudios experimentales, pero las diferencias entre las cepas tambien parece jugar un importante rol en algunas enfermedades. Resultados de laboratorio fueron confirmados por observaciones hechas en el campo sobre poliomielitis, viruela, fiebre aftosa, peste bovina y enfermedad de Newcastle; Es probable que la enfermedad de Marek. la bronquitis infecciosa aviar y otras numerosas enfermedades seandiseminadas de la misma manera. La diseminación a grandes distancias por corrientes de aire puede ser influenciada, hasta cierto punto, por la virulencia del agente causal y por la tasa de acentamiento para particulas de un tama?o, las cuales son óptimas para su acentamiento en el lugar de predilección del organismo específico. Mas aun, factores locales geográficos y climáticos pueden modificar grandemente los patrones de distribución de enfermedades diseminadas por el aire durante grandes epidemias ó epizootias: Se citan como ejemplos brotes específicos.

Résumé Il a été démontré qu'un nombre croissant de maladies humaine et animale sont dísséminées par des microorganismes en suspension dans l'atmosphère. La viabilité de tels agents pathogènes décroit progressivement en fonction de l'influence des facteurs physiques et autres qui sont énumérés dans ce texte. L'humidité relative influence fortement cette possibilité de survie comme l'ont montré des études expérimentales, mais des différences de souches semblent aussi jouer un r?le important pour certaines maladies. Les résultats expérimentaux ont été confirmés par des observations faites sur le terrain à propos de la poliomyélite, la variole, la fièvre aphteuse, la peste bovine et la maladie de Newcastle; il est probable que la maladie de Marek, la bronchite infectieuse aviaire et de nombreuses autres infections se répandent de la même manière. La dissémination à longue distance par les courants aériens peut être influencée, dans une certaine mesure, par la virulence de l'agent causal et par le pourcentage de particules dont la taille est optimale pour leur arrivée au site d'élection du microorganisme spécifique. En outre, des facteurs géographique et climatique locaux peuvent grandement modifier le schéma épidémiologique des maladies disséminées par voie aérienne; des foyers spécifiques sont cités en example.


Based on a paper presented at a Meeting of the Central Canada Veterinary Association on 9th December 1970.  相似文献   
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