THE EFFECTS OF TANNIC ACID ON THE EFFECTIVENESS OF EGG FERTILIZATION AND REMOVING CARP EGG ADHESIVENESS

Abstract

Egg adhesiveness is one of the major problems in carp artificial breeding. The appropriate elimination of egg adhesiveness impacts the effectiveness of the breeding. This article discusses two used methods of carp egg adhesiveness removal: tannic acid+water and milk+water+salt solutions. Milk, water and salt solution was based on the following proportions: 1 litre of milk + 7 litres of water +50g of NaCl. Adhesiveness is removed from fertilized eggs in bowls by mixing them with geese feathers for no shorter than 60 minutes. The tannic acid solution was prepared by mixing 7 grams of tannic acid powder with 5 litres of water. 1 litre of solution is immediately poured into a bowl with fertilized eggs. Adhesiveness is removed from fertilized eggs in bowls by intensively mixing them for 10 minutes. After fertilization and removal of adhesiveness, the eggs were transferred into Weiss jars. The results showed that during the process of incubation, 3.7 million eggs were fertilized; out of them 1.6 million were rid of adhesiveness by milk solution, 2.1 – by tannic solution. It is plausible that unfavourable environmental conditions influenced the low egg vitality. 750 000 (47%) carp larvae hatched from milk solution treated eggs, while 800 000 (38%) of larvae hatched from the eggs treated with tannic solution.

Keywords: fertilization, adhesiveness, tannic acid, common carp

Article DOI: http://doi.org/10.15544/RD.2017.016