Combined effect of temperature, salinity and density on the growth and feed utilization of Nile tilapia juveniles (Oreochromis niloticus)

Abstract

Based on Box-Behnken experimental design and response surface method, the joint effect of temperature (16-36°C), salinity (0-22 ppt) and rearing density (200-1000 fish.m À3 ) on the specific growth rate (SGR) and feed conversion rate (FCR) of Nile tilapia juveniles were studied under laboratory conditions. The entire experiment lasted for 1 month (30 days). Results showed that the linear and quadratic effects of temperature, salinity on both growth and feed utilization were highly statistically significant (P < 0.01). The linear and quadratic effect of rearing density on the growth was highly significant (P < 0.01); the linear effect of rearing density on feed utilization was significant (P < 0.05), but the quadratic effect nonsignificant (P > 0.05). Interactions between temperature and salinity, and between salinity and rearing density on the growth statistically differed from zero (P < 0.05). Interactions between temperature and salinity, between temperature and density on feed utilization was significant (P < 0.05). Model equations of the growth and feed utilization on temperature, salinity and density were established, with the coefficient of determination being 98.34% for growth and 98.11% for feed utilization, and could be applied to projection. The optimal temperature/salinity/density combination was obtained utilizing statistical optimization approach: 29°C/6 ppt/500 fish.m À3 , at which the maximal specific growth and feed utilization reached 4.228%.d À1 and 0.520 respectively, with the desirability being 0.989.

Influence of water salinity on the survival of embryos and growth of the sichel larvaePelecus cultratus(L.) under controlled conditions

“…Euryhaline fish are very tolerant to water salinity, both during the embryonic development and larval growth (Alderdice ). An excellent example of such a fish is the Nile tilapia Oreochromis niloticus , which – despite being a freshwater fish – tolerates water salinity up to 20 ppt (Watanabe & Kuo ; Watanabe, Kuo & Huang ; Suresh & Lin ; El‐Sayed ; Jun, Pao, Haizhen, Ruiwei & Hui ). Likewise, early developmental stages of such fish as Eurasian perch Perca fluviatilis , burbot Lota lota , salmonid fish ( Salmonidae ) (Morgan & Iwama ), whitefish Coregonus lavaretus , stickleback (Klinkhardt & Winkler ; Jobling ) are much more tolerant to water salinity than cyprinid fish.…”

温度和喂食影响摩拉吧笛鲷体长体重关系和肥满度的研究

“…Among abiotic factors, any change in ambient water temperature has the greatest effect on the physiological properties of fish (Johnston, 2006;Arnason et al, 2009;Jun et al, 2012;da Costa et al, 2016;Mazumder et al, 2015b;Zhang et al, 2015). Quite apart from temperature, the quality of food is thought to be another important determinant of fish physiology and ultimately their growth (Kooijman, 2000;Byström et al, 2006;Englund et al, 2011).…”

Use of response surface methodology to study the combined effects of temperature and salinity on hatching and deformity of the hybrid grouper,Epinephelus fuscoguttatus(♀) × Epinephelus polyphekadion(♂)

“…() found that the interactive effects of temperature and salinity were significant on the hatching of the fertilized eggs of Sepia pharaonis . Interaction can significantly change the growth and feed utilization of tilapia juveniles (Jun et al., ; Likongwe et al., ). Effects of interaction were significant during the early development of Pinctada martensii (Wang et al., ), Argopecten irradia (Tettelbach & Rhodes, ) and Ruditapes philippinarum (Sang et al., ).…”

“…It is well known that the interaction of different environmental factors causes synergetic effects on aquatic animals (Fiess et al, 2007;Jun et al, 2012). Full factorial designs are often used to study the interaction between temperature and salinity (Likongwe et al, 1996;Watanabe et al, 1993), showing the quadratic effects of factors or a combination of optimal factor levels (Jun et al, 2012).…”

“…It is well known that the interaction of different environmental factors causes synergetic effects on aquatic animals (Fiess et al., ; Jun et al., ). Full factorial designs are often used to study the interaction between temperature and salinity (Likongwe et al., ; Watanabe et al., ), showing the quadratic effects of factors or a combination of optimal factor levels (Jun et al., ). Response surface methodology (RSM) is usefully applied as an effective tool for the optimization of a process when the independent variables can exert a combined effect on the desired response (Caporaso et al., ).…”