Fig. 2

Locomotory behaviour of six zebrafish strains at one month post fertilisation.

A) Mean distance swum in a 60-minute time interval by 1 month-old AB, ABstrg, casper, EK, TU and WIK juveniles. ABstrg swam significantly less than all other strains apart from casper. casper swam significantly less than EK, TU and WIK. For the statistics refer to table 2. AB n = 39; ABstrg n = 39; casper n = 37; EK n = 19; TU n = 39, WIK n = 27. B) Mean swimming speed of 1 month-old AB, ABstrg, casper, EK, TU and WIK juveniles during a 60-minute experiment. ABstrg swam significantly slower than the other fish strains. For the statistics refer to table 2. AB n = 39; ABstrg n = 39; casper n = 37; EK n = 19; TU n = 39, WIK n = 27. C) Mean time spent swimming during a 60-minute experiment for 1 month-old AB, ABstrg, casper, EK, TU and WIK juveniles. ABstrg, EK, TU and WIK swam for significantly more time than AB and casper. For the statistics refer to table 2. AB n = 39; ABstrg n = 39; casper n = 37; EK n = 19; TU n = 39, WIK n = 27. D) The distance swum every 5 minutes for each strain as function of time. Values are plotted every 300 seconds in a 60-minute experiment for 1 month-old AB, ABstrg, casper, EK, TU and WIK juveniles. AB, ABstrg, casper, EK and WIK fish show smoother locomotion curves than TU. For the statistics refer to table 1. AB n = 39; ABstrg n = 39; casper n = 37; EK n = 19; TU n = 39, WIK n = 27. E) Graph showing the correlation between fish size (measured by surface area) and swimming speed during a 60-minute experiment for one month old AB, ABstrg, casper, EK, TU and WIK juveniles. There is no correlation between size of fish and swimming speed for any strain analysed. We calculated the Pearson product-moment coefficient for each strain (r) with speed as independent variable and surface as dependant variable. AB r = 0.23 NS; ABstrg r = -0.28 NS; casper r = 0.07 NS; EK r = -0.12 NS; TU r = 0.17 NS; WIK r = 0.3 *p = 0.05. AB n = 29; ABstrg n = 39; casper n = 32; EK n = 19; TU n = 38, WIK n = 26. F) Relative size of 1 month-old juvenile fish, calculated by measuring the average number of pixels making up their surface area. casper mutant fish have a significantly smaller surface area than AB, ABstrg, EK, TU and WIK. Student′s t-test: AB vs ABstrg NS; AB vs casper ***p<0.001; AB vs EK NS; AB vs TU NS; AB vs Wik *p<0.05; ABstrg vs casper ***p<0.001; ABstrg vs EK NS; ABstrg vs TU NS; ABstrg vs WIK NS; casper vs EK ***p<0.001; casper vs TU ***p<0.001; casper vs WIK ***p<0.001; EK vs TU NS; EK vs WIK NS; TU vs WIK NS.