Background and Objectives
Honey bees hygienic behavior is the primary natural defense against Varroa mite, American foul brood and chalk brood disease and are controlled by genetic and environmental factors. Hygienic behavior includes of three stages of detecting, uncapping and removing of infected or dead brood from the colony. However, this behavior is quite rare, with only 10% of unselected colonies showing high levels of hygiene. Beekeepers can potentially increase this by screening colonies for hygiene and breeding from the best. 
Materials & Methods
In this study hygienic behaviors and infestation rates of Varroa mite is evaluated in bee colonies. The study was accomplished on 100 honey bee colonies. The rate of uncapping and removal of dead broods was determined in resistant and control colonies. To determine the hygienic behavior, liquid Nitrogen was used to kill pupae. The number of uncapped and discharged cells were counted in the three periods of 24, 48 and 72 hours after the pouring of liquid nitrogen.
Results
According to results the examined colonies exhibited noticeable phenotypic variation for Hygienic behavior. At the first stage (spring) %21 and in the second stage (summer) %18 of colonies showed good hygienic behavior. Uncapping rates in days showed significant correlation with removing rates in the same recording day (P<0.01). Varroa mite population was evaluated in in three stages of spring, summer and autumn. The result demonstrated that the colonies with high level of hygenic behavior had the lowest infestation rates of Varroa mite (P<0.05). Moreover, the results showed that the contribution of hygienic behavior in the control of Varroa mite populations was %26.
Discussion
The results of this research and other studies conducted by other Iranian researchers show that Iranian honeybee has shown higher hygienic behavior against Varroa mite. In this study resistant and stable colonies were selected for bee breeding projects at the end of the year. By selecting and implementing good breeding programs, it is possible to increase the rate of these behaviors in order to create Varroa mite-resistant populations. It seems that hygienic colonies selecting for resistance to Varroa mite will have satisfactory results in the future.