To reduce the risk of zoonoses, it is necessary to understand the infection process, including the ecology of animals and vectors (i.e., the \'One Health\' approach). In temperate climates, ticks are the major vectors of zoonoses, so factors determining their abundance, such as host mammal abundance and microhabitat conditions, should be clarified. Sika deer (Cervus nippon) are a major tick host and are rapidly expanding their distribution in Japan. We established 12 plots along a gradient of sika deer abundance in Tochigi Prefecture, Japan. We monitored the occurrence of mammal species with camera traps and sampled questing ticks on a monthly basis by flagging along three transects (center of a trail, forest edge, and forest interior) at each site from April to November 2018. The camera traps recorded 12 mammal species, predominantly sika deer. Five Haemaphysalis species and three Ixodes species were sampled. The numbers of ticks sampled were explained by the photographic frequency of sika deer, and partly by that of other mammal species, depending on tick species and their developmental stages. The numbers of sampled adult and nymphal ticks were the highest at the forest edge, where vegetation cover was greatest. Thus, vegetation management in tick habitats and the control of sika deer populations may reduce tick abundance.

Mammalian zona pellucida (ZP) is composed of three to four glycoproteins, which plays an important role during fertilization. Mutations in the genes encoding zona proteins are reported in women with empty follicle syndrome, degenerated oocytes and those with an abnormal or no ZP further emphasizing their relevance during fertility. Immunization with either native or recombinant ZP glycoproteins/proteins leads to curtailment of fertility in various animal species. Observed infertility is frequently associated with ovarian pathology characterized by follicular atresia and degenerative changes in ZP, which may be due to oophoritogenic T cell epitope(s) within ZP glycoproteins. To avoid ovarian dystrophy, B cell epitopes of ZP glycoproteins have been mapped by using bio-effective monoclonal antibodies. Immunization with the immunogens encompassing the mapped B cell epitopes by and large led to amelioration of follicular atresia. However, their use for human application will require more rigorous research to establish their safety and reversibility of the contraceptive effect. Nonetheless, to minimize human-animal conflicts, ZP-based contraceptive vaccines have been used successfully in the population management of free-ranging animal species such as feral horses, white-tailed deer and elephants. To control zoonotic diseases, attempts are also underway to control the population of other animal species including stray dogs, which acts as one of the major vectors for the rabies virus.