INTERSPECIFIC HYBRIDIZATION OF THE TIGER PRAWNS PENAEUS-MONODON AND PENAEUS-ESCULENTUS

Interspecies hybrids were produced by artificial insemination of Penaeus monodon females with P. esculentus males. Successful spawnings were achieved from two of the 13 matings attempted. Hatch rates were low (< 4%) but 85% of the vigorous larvae produced survived to PL1. The hybrid identity of the larvae was confirmed by allozyme analysis at five diagnostic loci. Tank-reared juveniles grew at an overall rate of approximately 0.09 g day-1 to a weight of 10 g in tanks until the prawns were stressed at 4.5 months. A number of viral diseases were expressed subsequently, including IHHNV, and the experiment was terminated. There was no indication of hybrid vigour in growth rates, and the high growth rate of P. monodon was not combined simply with the colour patterns of P. esculentus. A variety of body colour and pattern variants, ranging between those of P. monodon and P. esculentus, was observed in the hybrids.