Effects of delayed feeding on growth and survival of Channa striatus (Bloch) larvae

Abstract

Abstract. Newly hatched Channa striatus (Bloch) were tested for survival and growth under various delayed feeding regimes. Channa striatus larvae were found to be extremely tolerant to the delay in initial feeding. About 9% of the larvae died when initial feeding was delayed by 2 days after yolk absorption. However, mortality progressively increased with further delays in first feeding. Only 26% of larvae took food when it was offered 11 days after yolk absorption.‘Point of no Return’was reached only on the 14th day of starvation.

Genetic structure of the snakehead murrel, Channa striata (channidae) based on the cytochrome c oxidase subunit I gene: influence of historical and geomorphological factors

“…Hence, in order to effectively conserve and manage the fish, vital information on relevant population genetics is required, specifically through assessment of its genetic diversity and structuring for potential brood-stock identification. Previous studies have focused on reproductive biology ( Ali, 1999 ), medical and pharmaceutical properties ( Baie and Sheikh, 2000 ; Michelle et al , 2004 ), biochemical composition ( Zuraini et al , 2006 ; Zakaria et al , 2007 ), ecology ( Lee and Ng, 1994 ; Amilhat and Lorenzen, 2005 ), breeding ( Haniffa et al , 2000 ), diet ( Roshada, 1994 ; Arul, 2008 ) and morphological characters ( Chandra and Banerjee, 2004 ), with only limited available information on population genetics of the species, especially in Malaysia. Ambak et al (2006) and Mat Jais et al (2009) , when examining the genetic structure of snakeheads from Peninsular Malaysia based on RAPD and RFLP data, reported a positive co-relation between hydro-geographic factors (mainly due to the Titiwangsa Mountain Range) and population genetic differentiation, respectively.…”

Growth, survivorship, and predator avoidance capability of larval shortnose sturgeon (Acipenser brevirostrum) in response to delayed feeding

“…shortnose sturgeon, larval bloch, Channa striatus (a freshwater species) also had a PNR [61] well above that predicted by McGurk's regression equation. Shan et al [62] used degree-days to compare PNR across species.…”

“…Our observed PNR of 42 days post-fertilization was significantly longer than the predicted PNR of 30.7 days post-fertilization ± 0.43 SE by McGurk’s original regression equation (t s = 0.5 + 1.3*t y ; where t s is the time from fertilization to PNR and t y to yolk absorption). Like shortnose sturgeon, larval bloch, Channa striatus (a freshwater species) also had a PNR [ 61 ] well above that predicted by McGurk’s regression equation. Shan et al [ 62 ] used degree-days to compare PNR across species.…”

“…The oil globule (which was 45% ± 0.03 SE of the larval shortnose sturgeon total yolk volume at hatch) is absorbed more slowly than yolk during food deprivation and may contain higher energy than yolk proteins [ 64 , 65 ]. Thus, it may aid in prolonging or even avoiding PNR [ 36 , 60 , 61 , 64 , 66 ]. Alternatively, this variation may reflect differences in the quality of yolk constituents as a result of differences in feeding habit and selective pressures, between freshwater and marine fish.…”

“…Shortnose sturgeon have larger eggs and a much longer time to PNR compared to the 25 species analyzed by McGurk [60]. Lengthened time to PNR may be related to the presence of a large oil globule within the eggs of shortnose larvae similar to some other fish larvae [60][61][62][63]. The oil globule (which was 45% ± 0.03 SE of the larval shortnose sturgeon total yolk volume at hatch) is absorbed more slowly than yolk during food deprivation and may contain higher energy than yolk proteins [64,65].…”