Effects of temperature on the embryonic development of the striped trumpeter (Latris lineata Bloch and Schneider, 1801)

Eggs collected from females of striped trumpeter (Latris lineata) that were induced to ovulate with LHRHa were inseminated and incubated at six different temperatures ranging from 8.1 to 18.1 degrees C. Mortality was recorded for four embryonic periods (I: cell cleavage, II: epiboly, III: organogenesis and IV: organogenesis-growth). A power law was used to approximate the relationship between temperature and developmental time to four stages of embryonic development (visible peripheral periblast, yolk plug closure, heart beat and hatching). These models may have application for the ageing of striped trumpeter eggs. The time taken for 50% of embryos to hatch at 8.1, 10.5, 12.3, 14.1 and 16.2 degrees C was 13.0, 8.7, 6.4, 5.1 and 4.1 days, respectively. Embryos incubated at 18.1 degrees C developed abnormally and almost all died during epiboly. Embryonic mortality was high during epiboly at 8.1, 16.2 and 18.1 degrees C and during organogenesis-growth at 8.1 degrees C. Survival to hatch was highest at 10.5, 12.3 and 14.1 degrees C. The standard length and body depth at vent at hatching decreased with increasing temperatures but yolk volume was largest at 12.3 degrees C. The optimal temperature range for the incubation of striped trumpeter eggs was 10.5 to 12.3 degrees C, which is close to the mean sea-surface temperature during the spawning season (11.42-12.66 degrees C) and the ambient temperature experienced by the broodstock at spawning (11 degrees C). (C) 1999 Elsevier Science B.V. All rights reserved.