ARS | Publication request: Utilization of quail and chicken embryos for the detection of botulinum toxin type A activity

Submitted to: World Poultry Congress Proceedings
Publication Type: Proceedings
Publication Acceptance Date: December 20, 2007
Publication Date: June 29, 2008
Citation: Buhr, R.J., Bourassa, D.V., Cox Jr, N.A., Phillips, R.W., Richardson, L.J., Kelley, L.C., Wilson, J.L. 2008. Utilization of quail and chicken embryos for the detection of botulinum toxin type A activity. World Poultry Congress Proceedings. 64:(Suppl. 2)P.195.

Technical Abstract: Clostridium botulinum is a ubiquitous microorganism which can produce botulinum toxins and the ability to assess toxin activity in a food sample is critical. As an alternative to the mouse assay incubating quail (Coturnix coturnix japonica) and chicken (Gallus gallus domestics) embryos were evaluated. Quail were incubated for 15 d and chickens for 18 d under standard conditions. In a previous hatch quail chicks weighed 7g and chicken chicks weighed 48g, a 6.85 fold difference. To provide the same dosage (ng of toxin per g of embryo) quail embryos were injected at 0, 0.5, 1, 5, 10, 20, 50ng and chicken embryos at 0, 3.42, 6.85, 34.25, 68.5, 137, 342ng. Embryo viability was reassessed daily post-injection (PI). Day 2 PI quail embryos injected at 0ng hatched 90%, 0.5ng 25%, 1ng 30%, and 5 to 50ng 0%; while chicken embryos injected at 0ng hatched 60%, 3.4ng 30%, 6.8ng 25%, 34ng 40%, 68ng 5%, 137ng 25%, and 342ng 0%. Day 4 PI quail embryos injected at 0ng hatched 90%, 0.5ng and 1ng 35%, 10ng 5%, and 5ng, 20ng or 50ng 0%; while chicken embryos injected at 0ng hatched 100%, 3.4ng 50%, 6.8ng 56%, 34ng 55%, 68ng 5%, 137ng 40%, and 342ng 0%. Results demonstrate that these embryos are effective vertebrate models to detect the activity of botulinum type A toxin.