First attempt of interspecific hybridization between the shrimps Penaeus kerathurus Forskal,1775 and Penaeus japonicus Bate,1888

Abstract

This paper reports preliminary studies designed to evaluate hybridization through natural mating and artificial insemination between female Penaeus japonicus Bate, 1888 and male Penaeus kerathurus Forskäl, 1775. Although both species were able to mature in captivity, natural copulation was not achieved. Different techniques, including manual squeezing in the base of the fifth pair of pereiopods, electrical stimulation and dissection, were used for the artificial insemination experiments. However, only dissection gave spermatophores. Stained sperm showed no malformations and its viability was very high. Seven out of 10 inseminations (70%) produced eggs, but the development of embryos was abnormal. It is suggested that the high genetic distance between these species is responsible for these results.

Interspecific hybridization of decapod crustacean species with commercial interest—A review

“…56 Artificial breeding, which involves selective breeding and inbreeding, can reduce genetic variability from generation to generation, leading to a higher risk of inbreeding and a decrease in hatching rates. 39 To address this problem, interspecific hybridization, which involves genetic manipulation, can be used as an option for stock improvement. 39 In aquaculture, genetic analysis is often used to predict the hybridization potential of two species 58,59 but it is not always a reliable indicator.…”

“…39 To address this problem, interspecific hybridization, which involves genetic manipulation, can be used as an option for stock improvement. 39 In aquaculture, genetic analysis is often used to predict the hybridization potential of two species 58,59 but it is not always a reliable indicator. 60 The study conducted by Graziani et al 30 showed that hybridization of M. roserbergii and M. carcinus was not successful either by natural mating or through AI despite having similarities in genetic characters.…”

“…39 Sexual pheromones, which are responsible for mating behaviour in several decapod species, are released in general by females [40][41][42] and detected by the males' first antenna or whip antennular (olfactory organs). 39,43,44 Particularly in shrimps, distance pheromones can be released both by females to stimulate searching and/or courtship behaviours in males, 40 or by males to attract females. 45,46 Postzygotic barriers are those that prevent the zygote from developing into a reproductive adult such as hybrid unviability or hybrid sterility.…”

“…35,49,112,125 The spermatophore used in the AI process is obtained by manually squeezing the base of the fifth pair of pereiopods, dissection or through electrical shock. 11,39 According to Red on et al, 39 dissection technique is a better method of obtaining spermatophore than the use of manual technique or electrical stimulation. This was because the latter methods attempted to obtain spermatophore for interspecific hybridization of two Penaeid species (female Penaeus japonicus and male Penaeus kerathurus) only obtained milts with no spermatophore following treatment with 1.5 V and 200 mA.…”

“…38 Pheromones, animal maturation and the moult stage are some factors that influence natural copulation in crustaceans. 39 Sexual pheromones, which are responsible for mating behaviour in several decapod species, are released in general by females [40][41][42] and detected by the males' first antenna or whip antennular (olfactory organs). 39,43,44 Particularly in shrimps, distance pheromones can be released both by females to stimulate searching and/or courtship behaviours in males, 40 or by males to attract females.…”