Effects of natural infection by L. borgpetersenii serovar Hardjo type Hardjo-bovis and L. interrogans serovar Pomona, and leptospiral vaccination, on sheep growth

In the absence of an overall growth response to vaccination, widespread adoption of vaccination would unlikely yield an economic response at the industry level. However, the inconsistency observed when comparing animals based on their exposure status suggests that the actual effect of leptospirosis on growth is difficult to predict. A study of the effect on sheep reproduction is needed to fully assess the effect of vaccination on sheep production.