Commission Decision of 30 March 1995 fixing the criteria for the testing of poultry for slaughter originating in a surveillance zone for Newcastle disease, in application of Article 5 (3) of Council Directive 91/494/EEC (Text with EEA relevance) (95/117/EC)

ANNEX U.K.

1. Sampling U.K.

At leat 60 samples comprising at least 30 cloacal swabs and 30 tracheal swabs shall be taken from each flock. At least 60 birds shall be sampled. The samples shall be taken five days before slaughter, and transported, chilled, but not frozen to the National Newcastle Disease Laboratory for testing.

2. Treatment of samples U.K.

Not more than five samples of each type may be pooled. Swabs should be placed in sufficient antibiotic medium to ensure full immersion and after agitation left for about two hours at ambient temperature (or longer periods at 4^o C) and then clarified by centrifugation (e.g. 800 to 1 000 x g for 10 minutes).

3. Antibiotic medium U.K.

A typical example for cloacal swabs is: 10 000 units/ml penicillin, 10 mg/ml streptomycin, 0,25 mg/ml gentamycin and 5 000 units/ml mycostatin in phosphate buffered saline at pH 7,2 to 7,4. 50 μg/ml oxytetracycline may be added. The antibiotic concentrations can be reduced five-fold for tracheal swabs. It is imperative when making the medium that the pH is checked after the addition of the antibiotics and re-adjusted.

4. Virus isolation in embryonated fowls' eggs U.K.

The clarified supernatent fluid should be inoculated in 0,2 ml amounts into the allantoic cavity of each of a minimum of four embryonated, fowls' eggs which have been incubated for 8 to 11 days. Ideally, these eggs should be obtained from a specific pathogen free flock, but when this is impracticable it is acceptable to use eggs obtained from a flock shown to be free of antibodies to Newcastle disease virus. The inoculated eggs are held at 37 ^oC and candled daily. Eggs with dead or dying embryos as they arise, and all remaining eggs four days after inoculation, should be chilled to 4 ^oC and the allantoic-amniotic fluids tested for haemagglutination activity.

5. Interpretation U.K.

The test should be regarded as negative if no haemagglutination activity is detected and no virus is isolated. Isolation of a Newcastle disease virus means that the flock is treated as a suspect flock and subjected to the requirements of Article 4 of Council Directive 92/66/EEC(1). If the virus proves to be of vaccinal origin, the sampling and testing should be repeated.

(1)

OJ No L 260, 5. 9. 1992, p. 1.