A METHOD FOR ARTIFICIAL INSEMINATION OF Macrobrachium PRAWNS AND ITS POTENTIAL USE IN INHERITANCE AND HYBRIDIZATION STUDIES1

A simple method for artificial insemination of Macrobrachium prawns is described and observations on breeding behavior, spermatophores and spawning are reported. The insemination procedure involves mechanical extrusion and attachment of sperm masses and has proved successful for intraspecific crosses of M. rosenbergii and M. acanthurus. Further, more than one female can be bred simultaneously by using sperm from a single male, an important consideration for inheritance studies. The following interspecific crosses also have been attempted with this method but without success: M. acanthurus ♂ x M. rosenbergii ♀, M. rosenbergii ♂ x M. acanthurus ♀, M. acanthurus ♂ x M. ohione ♀, M. rosenbergii ♂ x M. ohione ♀, and M. ohione ♂ x M. rosenbergii ♀. Manually placed sperm masses were retained through spawning in a few of the hybridization attempts, but fertilization was not obtained. However, since only a relatively small number of crosses have been attempted, additional efforts in this area appear warranted. Specifically, we believe that trials with more closely related species than those tested to date might prove more fruitful. Also, the potential use of this procedure in captive breeding or hybridization of other species of shrimp is noted.