River Bray fisheries survey 1978-80

This is the River Bray fisheries survey 1978-80 report produced by South West Water Authority in 1981. This report aims to assess the possible effects of new abstraction conditions at Leahamford on the fish communities of the River Bray, surveys have been carried out in 1978, 197S and 1980. Field work was done in August and September each; year. Abstraction began in summer 1979. On the River Bray one site upstream and three downstream of Leahamford were chosen. One site on the River Mole was surveyed and is considered as a control site, being not directly affected by abstraction. The sketch map shows these sites in relation to Leahamford.

Binding of radio-iodinated gonadotropin to the ovary of exotic carp (Cyprinus carpio Lin.)

Heterologous murrel gonadotropic hormone (m-GtH) binds to common carp oocyte plasma membrane and enhances steroid secretion. With increasing concentration of radio-labelled hormone the receptor binding is also found to increase linearly up to a certain concentration and then decrease. The [¹²⁵I] murrel GtH binding characteristics to a preparation of common carp ovarian plasma membrane shows saturability with high affinity. Scat chard plot analysis gave dissociation constant (Kd) of 0.81 X 10(super -9) M and maximum binding capacity (MBC) of 22.05 f mole/mg protein.