Effects of Salinity on Five Hormones in the Hemolymph of Female Eriocheir sinensis during Reproduction

Abstract

Background: The Chinese mitten crab (Eriocheir sinensis) is widely distributed in the coastal and coastal water of China and has important economic values. Salinity is the key environmental factor affecting the mating and spawning of E.sinensis. During the mating and spawning of E. sinensis, the hormone changes in the body are usually accompanied, but there is no report about the effects of salinity on related hormones in the process of breeding of E. sinensis. Methods: Mating salinity including 0‰, 2‰, 4‰, 6‰ and spawning salinity such as 3‰, 6‰, 9‰, 12‰, 15‰, 18‰, 21‰ were set up, three parallel groups are set for each salinity, 10 female and 5 male crabs are put in each tank. 5 samples were gathered to analyze the contents of 17α,20β-dihydroxy-4-pregnene-3-one (DHP), Gonadotropin (GTH), Prostaglandins (PG), Estradiol-17β (E2) and Testosterone (T) in the hemolymph of female E. sinensis after mating and spawning. Result: The contents of DHP, E2, PG and T in female crabs hemolymph decreased first and then added with the increase of salinity before spawning. DHP, PG and E2 added first and then declined with the increase of salinity after spawning. When salinity was 6‰, the contents of DHP, PG, E2 and T in the hemolymph of female crabs before spawning reached the highest, the contents of DHP and PG decreased and E2 and T increased after spawning. The comprehensive study indicated that salinity had a certain effect on five hormones in the hemolymph of female E.sinensis during reproduction, five hormones didn’t change significantly in the process of mating, DHP, GTH and PG were involved during the spawning of E.sinensis.