SEX RATIO AND SEX UAL DIMORPHISM IN GROWTH OF GIANT GOURAMI (Osphronemus goramy) AND ITS IMPLICATION FOR SELECTIVE BREEDING STRATEGY.

Sularto, Rita Febrianti and Suharyanto
Research Intitute for Fish Breeding.
Sukamandi - Subang, West Java
Post Code  41263 Ph. 0260-520500 Fax:0260-520662
E-mail : sularto61@yahoo..com

Adult size of giant gourami (Osphronemus goramy, Lac.) has a distinctive shape morphometric particularly in male fish, it is easy to distinguish between male and female. Giant gourami  males have the distinctive shape that is prominent forehead and thick lips. The shape differences are common symptoms found in some species of fish. This research aims to know the sex ratio and growth performance between male and female of giant gourami.

This research was conducted at the Research Institute for Fish Breeding in June 2014 until May 2015. Animal tests  were the four seed population  progeny from four different populations of giant gourami, namely : Kalimantan, Jambi, Majalengka and Tasikmalaya, aged 14 months. Eggs incubations and seed rearing using Standard Operational Procedures (SOP) of giant gourami seed rearing. Rearing of seed carried out for 14 months.

The results showed that there were differences in the growth of both the character of the standard length and weight between male and female (P <0.05).  Differences of growth in all four populations ranged from 4.74 to 5.67% for the standard length character and 14.10 - 16.52% for the weight of the character. Based on the ratio of sex, number of fish female more than the number of male: female 62.83 - 82.61% and male 17, 39 - 37.17%. However, when done as well as selection based on the growth character, then the proportion of male will be more than female (Table 2). Therefore, needed the special strategy for selective breeding program on the giant gourami so that obtained sex ratio in accordance with the expectations.