BRSV is a challenge, especially in young calves even when colostral antibodies are present.

John Ellis and the HIPRA R&D team have been working together in the design of the study and Ellis performed the experimental trial. The purpose of this study was to examine:

1) The efficacy in protecting calves from a virulent BRSV challenge after intranasal administration of NASYM to MDA+ calves in the first 2 weeks of life.

2) The longevity of the clinical immunity.

3) To characterize the immunological response to the vaccine before and after challenge.

Look at the amazing results obtained by J. Ellis and see how this information can help vets and farmers improve the outcome when facing BRSV.

The efficacy of NASYM against a virulent BRSV challenge was demonstrated in newborn calves vaccinated at the age of 7 to 17 days.

Protection was shown in terms of clinical signs, lung lesions, viral shedding, mortality, PaO2 and humoral response.

The longevity of the immunity was demonstrated at least until 10 weeks of age in the presence and the absence of MDA.