Disinfection of striped trumpeter (Latris lineata) eggs with glutaraldehyde

This study assessed the effect of immersing striped trumpeter eggs in 0 (control), 200, 400, 800, 1600 or 3200 ppm glutaraldehyde for 10 minutes, two days before hatching. High concentrations of glutaraldehyde (1600 and 3200 ppm) resulted in no eggs hatching and only 1% of eggs hatched after treatment with 800 ppm glutaraldehyde. Hatching success of eggs treated with 0, 200 or 400 ppm glutaraldehyde did not differ (77 ± 6%, n = 3). However, only 2% of larvae from the control treatment survived to day 5 post-hatching, compared to 45 and 69%, respectively of the larvae from the 200 and 400 ppm glutaraldehyde treatment. By day 9 post-hatching, larvae from the 400 ppm glutaraldehyde treatment had significantly higher survival (59%) than larvae from the 200 ppm glutaraldehyde treatment (28%). Thiosulphate citrate bile salt sucrose agar (TCBS) medium confirmed the presence of bacteria within the seawater medium, on all control eggs and on 83% of eggs disinfected with 200 ppm glutaraldehyde, but no bacterial colonies formed on eggs treated with 400, 800, 1600 or 3200 ppm glutaraldehyde. This study found highest survival of striped trumpeter larvae from eggs disinfected with 400 ppm glutaraldehyde and suggests that increased survival was a result of reduced bacterial loading.