nAb titres by serum neutralizing tests (SNTs), clinical reaction indexes (CRIs) and the percentage of protection.

a. The respective serum neutralization titres were determined against 30–300 TCID50 of the indicated BTVs and expressed as the dilution of serum giving a 50% neutralisation endpoint.b. The clinical reaction index (CRI) was determined according to Huismans et al [24]. See also materials and methods.c. The percentage of protection was determined as 100-RR, in which RR is the CRI of each sheep expressed as a percentage of that of the average control.d. BTVac-6 was previously named rgBTV6 [17].e. CombiVac is a combination of BTVac-1, BTVac-6, BTVac-8.