Interactions between temperature and size on the growth, size heterogeneity, mortality and cannibalism in cultured larvae and juveniles of the Asian catfish, Pangasianodon hypophthalmus (Sauvage)

Abstract

Temperature effects vary throughout the ontogeny, but are proportionally more variable during the early life stages than in older fish. The larvae of a few species have been studied but contrasting trajectories were observed, thereby making it difficult to predict how temperature impacts on the growth, survival and size heterogeneity in a particular species. This study examined these interactions in young [0.9 mg–1 g wet mass (WM)] Pangasianodon hypophthalmus, one of the most extensively cultured tropical fish. Fish were raised at five temperatures from 23 to 33 °C in a recirculated water system, fed in excess with a high‐energy feed (Artemia then a formulated feed, >50% protein), and examined at 1‐day (first feeding days) or 4‐day intervals (older fish). The temperature that produced the fastest growth (T°opt) was 31 °C at the start of exogenous feeding (0.9 mg); it increased to 32.7 °C at 8 mg then decreased by 0.7 °C for each 10‐fold increase of WM. Size heterogeneity was lower and survival was higher (70–85% from 0.9 mg to 1 g) when the temperature was close to T°opt. Comparisons with other species suggest that the slope of the relationship between T°opt and fish size has a strong latitudinal component, and may also reflect the fish sensitivity to oxygen.

Intracohort cannibalism and methods for its mitigation in cultured freshwater fish

“…Rearing temperature should fall within the thermal comfort zone, which is specific for a given species and population. Fish raised at different temperatures generally have different growth-feed ratios, thereby the comparisons of the survival rates between fish of identical ages is not informative, because they will be at a different level of ontogenetic development (Baras et al 2011a). However, due to the interval nature of this parameter, it is possible to rear fish closer to a lower or higher end of the comfort zone and, in this way, manipulate the metabolism rate.…”

“…In addition, the gastrointestinal content of a potential cannibal may be examined. In most species, fish of different sizes are differentially sensitive to handling, but handling generally has no significant effect on fish survival (Baras et al 2011a). However, special attention is needed when very small and fragile Percids larvae are examined, as they are by nature very sensitive to any handling and parameter alterations, which results in deaths (Król and Zieliński 2015) and may be mistaken for an outcome of cannibalism.…”

Business evaluation of Pangasionodon hypophthalmus nursery in Sukamandijaya Village, Subang

“…Jumlah wadah yang digunakan oleh para pembudidaya yaitu antara 10−17 bak per pembudidaya. Volume keseluruhan bak para pembudidaya yaitu 3.188 L−9.860 L. Menurut Baras et al (2011) dan Khan et al (2009) …”

Biology and culture of the clown loachChromobotia macracanthus(Cypriniformes, Cobitidae) : 4- Thermal biology of embryos and larvae

“…• C for a 10-fold increase of body mass; synthesis in Baras et al 2011). The value of T • opt can be further dependent on the feeding level (Kitchell et al 1977;Hogendoorn et al 1983) and on the energy or protein content of food (e.g.…”

“…Hurley 1999, 2000;Katersky and Carter 2007). Temperature impacts on growth, but also on size dispersal (Baras et al , 2011Baras and Florès 2006), which facilitates cannibalism (Hecht and Pienaar 1993;Baras and Jobling 2002). The mechanisms underlying these patterns are well understood, but the substantial variability between species makes it almost impossible to predict the adequacy of a particular temperature for a particular species or life stage in a particular environment, while such knowledge is indispensable to adjust rearing strategies in an aquacultural context.…”