Average weight of eggs laid by ticks engorged on groups of cattle immunized at weeks 0 and 4, showing anti-Bm86 antibody titers ranging from 1:640 to 1:81920. Animals included in the comparison were randomly selected from vaccinated and unvaccinated animals. The mean weight of eggs laid (black lines), confidence interval for 95% (grey squares) and standard deviation bars (in both senses) are indicated. A statistically significant difference (Friedman's test, indicated with an asterisk) was found between the negative control group and vaccinated animals. n: indicates the number of bovines that were grouped by antibody titers as indicated in the abscise axis.