Disinfection of Sparus aurata eggs with glutaraldehyde

This study was conducted to determine suitable conditions for disinfecting eggs of gilthead sea bream (Sparus aurata) with glutaraldehyde. Effects of the developmental stage (4-8 cells, morula, blastopore closure or heart beating), of the concentration (C = 200, 300 or 400 ppm) and of the duration of the glutaraldehyde treatment (T = 2 to 10 min) were investigated. Before the blastopore closure stage, egg manipulation and treatment induced mortality. After this stage, the toxicity of the glutaraldehyde treatment was negligible if the value of the product C x T was less than 1000. Above this value, the percentage of hatching and of normal larvae decreased and the percentage of imprisoned larvae increased. Toxic effects of glutaraldehyde varied according to the egg quality at the time of the treatment. It was concluded than 200 ppm glutaraldehyde for 4 min, at the blastopore closure stage or at the heart beating stage, were acceptable conditions for disinfecting gilthead sea bream eggs at 18 degree C.