Avian amyloidosis.

Although amyloid deposits have been described for more than a century and a half, its proteinaceous and fibrillar nature was not revealed until after 1950. Biochemical characterization of amyloids has brought to light that several non-related proteins can re-organize into amyloid fibrils. In some domestic and caged wild birds, and especially waterfowl, amyloidosis is a well recognized pathological disorder and is an important cause of death in Anseriformes.

The effect of a live vaccine on the horizontal transmission of Mycoplasma gallisepticum.

The effect of a live Mycoplasma gallisepticum vaccine on the horizontal transmission of this Mycoplasma species was quantified in an experimental animal transmission model in specific pathogen free White Layers. Two identical trials were performed, each consisting of two experimental groups and one control group. The experimental groups each consisted of 20 birds 21 weeks of age, which were housed following a pair-wise design.

The effect of vaccination with a bacterin on the horizontal transmission of Mycoplasma gallisepticum.

The effect of an inactivated vaccine on the horizontal transmission of Mycoplasma gallisepticum was quantified in a transmission model. Twenty non-vaccinated and 20 vaccinated 23-week-old specific pathogen free hens were housed in pairs, while five individually housed hens acted as a negative control group. Each pair consisted of a challenged chicken (10(4) colony forming units intratracheally) and a non-challenged susceptible contact bird.

Genotyping of Mycoplasma gallisepticum and M. synoviae by Amplified Fragment Length Polymorphism (AFLP) analysis and digitalized Random Amplified Polymorphic DNA (RAPD) analysis.

Mycoplasma gallisepticum (MG) and M. synoviae (MS) are the cause of considerable economic losses in the poultry industry. Molecular differentiation of avian Mycoplasma strains may be helpful in tracing infections and in the evaluation of implemented intervention strategies.

An experimental model to quantify horizontal transmission of Mycoplasma gallisepticum.

Before interventions to control horizontal transmission of Mycoplasma gallisepticum can be tested, a suitable experimental model should be available. Transmission dynamics in a flock can be quantified by two parameters: the average number of secondary cases infected by one typical infectious case (R0) and the number of new infections that occur due to one infectious animal per unit of time (beta). The transmission dynamics of M.