ISSN:0165-2176    

DOI:10.1080/01652176.1996.9694709

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Emerging infections are being recognized at an alarming rate. In the case of emerging viral infections involving free‐ranging wildlife, the intrusion of urban and agricultural enterprises into wildlife habitats appears to be playing a major role in the exchange of infectious agents of domestic to wildlife species and vice‐versa. It is important that the veterinary profession prepares itself to respond to the threatening challenges. Creation of a course which addressed the principles of infectious diseases, diagnostic medicine, epidemiology, public health, population medicine and control are all imperative. This paper attempts to address some of the principle subjects matter areas which should be included in the course offering.

ISSN:0165-2176    

DOI:10.1080/01652176.1996.9694710

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

In recent years, mass mortalities among seals and dolphins have been attributed to infections with different morbilliviruses. In all cases, these marine top predators were exposed to high levels of persistent lipophilic environmental contaminants accumulated through the food chain. This observation led to the hypothesis that a contaminant‐related suppression of the immune system might have contributed to the severity of the virus outbreaks. We conducted a semi‐field feeding experiment, in which we fed two groups of harbour seals (Phoca vitulina) fish with different levels of contaminants. During a period of 21/2 years, blood samples were taken at regular intervals, and the functioning of different compartments of the immune system was monitored and compared. We found impaired natural killer (NK) and specific T cell responses in the seals fed contaminated fish. This is the first demonstration of immunosuppression in mammals following chronic exposure to environmental contaminants at ambient environmental levels.

ISSN:0165-2176    

DOI:10.1080/01652176.1996.9694711

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:0165-2176    

DOI:10.1080/01652176.1996.9694712

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:0165-2176    

DOI:10.1080/01652176.1996.9694713

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:0165-2176    

DOI:10.1080/01652176.1996.9694714

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:0165-2176    

DOI:10.1080/01652176.1996.9694715

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:0165-2176    

DOI:10.1080/01652176.1996.9694716

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Populations of animals which live in the wild are regulated by many biotic and abiotic factors. Parasites are one of the biotic factors. Parasites may influence their hosts in different ways. They may cause the death of the host due to a direct lethal effect or an indirect effect. Direct lethal effects may occur if killing is a part of the life cycle of the parasite or if hosts and parasites have not developed an equilibrium. The introduction of hosts or parasites into a new environment with suitable hosts or parasites is an example. Death by parasitism may also be caused by a combination of the emaciating effects of parasites combined with factors such as bad weather conditions, environmental pollution or human handling. Parasites may also influence the behaviour of their hosts. If the hosts are intermediate hosts in the life cycle of the parasites, the alterations in behaviour may make them an easier prey for their predators, the final hosts. Parasites may also influence the reproductive success of the hosts. In this respect the relationship between the red grouse (Lagopus lagopus scoticus) and the caecal nematodeTrichostrongylus tenuishas been well worked out.

ISSN:0165-2176    

DOI:10.1080/01652176.1996.9694717

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:0165-2176    

DOI:10.1080/01652176.1996.9694718

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor