TAILIEUCHUNG - Photoperiod manipulation in the induced breeding of the rabbit fish (Siganus guttatus)

In teleosts, reproductive development is a continuous process throughout ontogeny and is regulated by pituitary gonadotropins (GtHs). It has been established that fish has two distinct pituitary GtHs that parallel vertebrate follicle stimulating hormone (FSH) and luteinizing hormone (LH) with respective structural similarities. | Journal of Fisheries science and Technology No. 4 - 2018 PHOTOPERIOD MANIPULATION IN THE INDUCED BREEDING OF THE RABBIT FISH (Siganus guttatus) Pham Quoc Hung¹, Hua Thi Ngoc Dung¹, Augustine Arukwe² Received: ; Revised: ; Accepted: ABSTRACT In teleosts, reproductive development is a continuous process throughout ontogeny and is regulated by pituitary gonadotropins (GtHs). It has been established that fish has two distinct pituitary GtHs that parallel vertebrate follicle stimulating hormone (FSH) and luteinizing hormone (LH) with respective structural similarities. In the present study we investigated the spawning of the Golden rabbit fish Siganus guttatus after exposure to different photoperiod regimes. The role of photoperiod on spawning was studied by exposing female fish to three light regimes: 16h:8h light and dark; 16h:8h dark and light; and 24h continuous light. At every first quarter of the lunar cycle (new moon), the groups exposed to the photoperiod were induced to spawn by the injection of hCG at 2000 IU/kg fish. We observed that only 24 h exposure to continuous light induced successful spawning in female injected with hCG. Fish exposed to the other light: dark regimes could not be induced to spawn. Overall, these findings suggest that continuous light can be a triggering factor for the induction of maturation and spawning of this species under aquaculture conditions. Keywords: Siganus guttatus, photoperiod, induced breeding, spawning. I. Introduction Reproduction processes are generally regulated by environmental factors that activate internal signals into action leading to the successful production of viable progenies. During seasonal breeding, the release of gametes through spawning are controlled by appropriate environment stimuli or may be induced by appropriate hormones (Zohar et al., 2009). Thus, the internal signals that control breeding are apparently similar in most teleost species. Nevertheless, there are .

TÀI LIỆU LIÊN QUAN
TỪ KHÓA LIÊN QUAN
TAILIEUCHUNG - Chia sẻ tài liệu không giới hạn
Địa chỉ : 444 Hoang Hoa Tham, Hanoi, Viet Nam
Website : tailieuchung.com
Email : tailieuchung20@gmail.com
Tailieuchung.com là thư viện tài liệu trực tuyến, nơi chia sẽ trao đổi hàng triệu tài liệu như luận văn đồ án, sách, giáo trình, đề thi.
Chúng tôi không chịu trách nhiệm liên quan đến các vấn đề bản quyền nội dung tài liệu được thành viên tự nguyện đăng tải lên, nếu phát hiện thấy tài liệu xấu hoặc tài liệu có bản quyền xin hãy email cho chúng tôi.
Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.