Table 2.
The survival and hatchability of embryos, fry survival and mutation rate of the channel catfish embryos microinjected at the one-cell stage with sgRNAs/Cas9 protein targeting the myostatin (MSTN) gene.
| Treatment | Embryos injected | Embryo mean time to death (days) ± SEM | Live embryos and Hatch | Mean time to hatch (days) ± SEM | Fry survival | Fry mean time to death (days) ± SEM | Mutated dead embryos | Mutated hatched fry | |
|---|---|---|---|---|---|---|---|---|---|
| N | N | % | % | % | % | ||||
| MSTN-1 | 82 | 6.1 ± 0.30a | 44 | 53.7 | 7.2 ± 0.08b | 90.9 | 19.0 ± 0.05 | 100 | 88.6 |
| MSTN-2 | 28 | 4.6 ± 0.46b | 7 | 25.0 | 7.0 ± 0.00ab | 100 | No mortality | 100 | 100 |
| MSTN-3 | 88 | 6.3 ± 0.22a | 50 | 56.8 | 6.9 ± 0.04a | 84.0 | 18.3 ± 0.58 | 100 | 88.0 |
| MSTN-Mix | 82 | 5.2 ± 0.27b | 27 | 32.9 | 7.2 ± 0.08b | 85.2 | 18.3 ± 0.81 | 100 | 96.3 |
| iCTRL | 137 | 6.2 ± 0.20a | 83 | 60.6 | 7.1 ± 0.04b | 95.2 | 19.6 ± 0.24 | — | — |
| nCTRL | 284 | 7.6 ± 0.08 | 220 | 77.5 | 7.4 ± 0.04 | 93.6 | 20.0 ± 0.03 | — | — |
Three sgRNAs were microinjected individually (MSTN-1, MSTN-2 and MSTN-3) and multiplexed (MSTN-Mix). Two controls were used; injected control embryos (iCTRL) were full-siblings to the treatment groups and were injected with the same solution and volume, but without sgRNA or Cas9 protein. The second control was not injected (nCTRL). Hatch % is the number of live embryos in each treatment divided by the total number of embryos in the same treatment and multiplied by 100. Pairwise comparisons of mean survival and hatch time were performed using Log Rank (Mantel-Cox) test with SPSS 23.0 software. All data are presented as the mean ± standard error (SEM). Means followed by different superscript letters are significantly different (p < 0.05). Mutation rates are calculated based on Surveyor analysis of all dead embryos and hatched fry.