| Ticks are well known vectors transmitting a great variety of infectious pathogens and causing serious damage to human and livestock. In ticks, vitellogenesis is the central events of reproduction and the key of egg production and population size. Thus, researches on vitellogenesis have important significance on the theoretical and practical level.A series of researches were conducted on the reproduction of female Haemaphysalis longicornis Neumann, including the structure and protein components of the genital system, ovary structure, protein concentration and components, as well as their variation during different developmental stages, purification and partial characterization of vitellin, as well as the effects of juvenile hormone and molting hormone on vitellogenesis, using scanning electron microscope (SEM), Bradford method, SDS-PAGE, gel filtration and ion exchange chromatography, topical application and an in vitro culture methods etc. The present research will provide foundation for further investigations on reproductive biology of ticks in the future. The main result were as follows:1. The reproductive system of female H. longicornis consisted of ovary, paired oviducts, vagina, receotaculun seminis, accessory glands and Gene's organ, which was similar basically to other tick species reported. However, the oviducts were manifestly widened distally as ampul late and the Gene's organ horns were saccules. The two characterizations were different from other hard ticks. The protein components of female genital system were complexity and biodiversity. However, the proteins of different parts were not only identity but also particularity.2. The ovary changed obviously with the developmental stages. In unfedadults, the ovary was a simple tube-like structure and the oocytes were small (5.90 μm). At the early stage of attachment, the ovary increased obviously and the diameter of oocytes was 38.70μ m, many developing oocytes appeared at the outside of the longitudinal groove. At mating stage, the ovary continue increased and elongated, some folds were apparent in a part of it; the diameter of oocytes increased slowly (73.33 μ m). After engorgement, the ovary developed rapidly, there were lots of oocytes collocated at the inside and outside of the longitudinal groove, oocytes which lied at the outside developed quickly. The diameter of oocytes increased rapidly (270.00μ m), which was about 3.7 times than that of mated female, and reached its maximum value (286.33 P m) at ovipositing stage. During this period, the ovary expanded into the major hemocoele.3 The protein level of the ovary varied obviously during female developmental stages. The concentration of protein was low (1.73 μ g/tick), and increased rapidly at the early stage after attachment (15.60μg/tick), which was about 9 times than that of unfed female. At the mating stage, the protein level continue increased (26.72 μg/tick). After engorgement on dO and d2, the proteins were 99.33 u g/tick and 372.49 μg/tick respectively, and reached its maximum level (1512.91 μg/tick) at ovipositing stage. On d 2 after oviposition, the protein level declined (1184.18μ g/tick).4. In unfed females, only one main ovary protein band was detected. At early feeding and mating stages, protein band multiplied obviously, and maximized on the day of engorgement. Fifteen main protein bands of the three stages were the same. From engorgement to oviposition, the main protein bands changed. Five protein bands were disappeared, the molecular weights of them were 97 KD, 91 KD,64 KD, 54 KD, 53 KD respectively. On d2, d3 after engorgement and d0, d2 after oviposition, the 9 main protein bands were the same.5. The vitellin (Vn) was firstly purified from eggs of H. longicornis, whichwas only one kind of protein. The purified protein could be stained by Black B and periodic acid-ShchifT (PAS), so it was an hcmoglycolipoprotcin. The vitellin was composed of eight polypeptides with the molecular weight of 112, 103, 80, 78, 71, 68,62 and 52 KDa.6. Juvenile...
|
PDF Full Text Request