Performance of Domesticated (Vietnamese) versus Nondomesticated (Cambodian) Snakehead, Channa striata (Bloch 1793) with Regard to Weaning onto Pellet Feed

Abstract

The Cambodian government banned snakehead, Channa striata (Bloch 1793) aquaculture in 2004 due to the unsustainable practices. Recent research in Vietnam led to increased sustainability with regard to hatchery practices and feeds. As part of a project to transfer technology from Vietnam to Cambodia, a study was conducted to compare survival and growth of domesticated snakehead from Vietnam with those of non-domesticated snakehead from Cambodia. Cambodian broodstock fish were collected from Mekong River and Tonle Sap, and F1 Cambodian fish from previous breeding were also used. Domesticated broodstock were purchased from Vietnam. Larvae from spawns of the four broodstocks (Vietnam, Mekong River, Tonle Sap and F1 Cambodian fish) were subjected to a weaning protocol developed in Vietnam in a 60-d hatchery phase, followed by a 6-month grow-out in ponds. The experimental results showed that Vietnamese fish (10.88 g.fish-1) grew significantly faster than Cambodian fish (3.24 to 4.96 g.fish-1) in the hatchery, followed by continued rapid growth in the grow-out phase (324.2 g.fish-1for Vietnamese fish versus 132.9 to 148.1 g.fish-1for Cambodian fish), largely due to increased feed consumption. Cannibalism rates ranged from 40–42 % in the hatchery phase except for Mekong River fish (significantly higher at 57 %) and 12–45 % in the grow-out phase (Vietnamese and F1 fish significantly lower than the other two treatments). It is not known whether differences were due to inherent genetic differences between wild Vietnamese and Cambodian fish, or to selective breeding (intentional or not) in Vietnam. Results will be useful information for Cambodian aquaculture policy to develop snakehead hatcheries and feed mills, following the lifting of the ban in 201