Meeting Abstract
Bio-control of prawns from the Macrobrachium genus over snails has been proven to be an efficient strategy under laboratory conditions, and is suggested to be used in field studies. We propose to use all-male populations of prawns generated by a temporary intervention via RNAi to silence the expression of the insulin-like androgenic gland encoding gene, creating broods with 100% male progeny. The advantages of the use of an all-male population lies in its temporal and non reproductive nature thus minimizing the risk of bio-invasions. Moreover, unlike females, male prawns do not tend to migrate and therefore will ensure predation within specific snail-infested sites. In addition, male prawns grow faster and larger than females, therefore a selective harvest of larger prawns would encourage the smaller prawns to grow faster and support the bio-control task while the larger prawns can be harvested as a byproduct for local human consumption. Here we present two case studies where all-male prawn populations could be used for different bio-control snail targets, snails carrying disease and invasive snail populations. The first case is the epidemiological challenge posed by the parasitic disease schistosomiasis (Bilharzia) that occurs mostly in Africa. The introduction of all-male populations of prawns is suggested in areas that suffer from high infection rates of freshwater snail Biomphalaria and Bulinus spp. , which serve as intermediate hosts of schistosomiasis. The second challenge is a globally devastating ecological and agricultural invasive species, the Apple snail Pomacea spp. The suitability of male prawns as bio-control agents has been studied under laboratory conditions with results suggesting that this can be a temporal sustainable solution from a conservation point of view.
