Abstract: The aim of this study was to assess the effects of transferring foreign genes on the growth characteristics, fatty acid content in the tissues and the distribution of intestinal microflora of mouse. The FAD3 gene-edited mice were used as the experimental group and the BDF1 mice were used as the control group. The mice were reared in the same condition and were killed at 45 days of age. The body weights, organ weights and unsaturated fatty acid contents in the muscles of the two groups of mice were measured, and the distribution of the cecum microflora was detected by PCR-DGGE targeting at the V₃ variable region of 16S rDNA. The results showed that the liver weight of the mice in the FAD3 group was significantly （P<0.05） lower than that in the control group, and there was no significant （P>0.05) difference in the weights of other organs and body weights between the two groups. The content of muscular n-6 polyunsaturated fatty acids （n-6 PUFAs） of the FAD3 group was lower than that of the control group, but there was no significant （P>0.05） difference; while the content of muscular n-3 PUFAs of the FAD3 group was significantly （P<0.05） higher than that of the control group. The cecum flora distribution of the two groups of mice displayed obvious individual differences, and no significant difference in cecum flora distribution was observed between the two groups. Anaerotaenia torta was a common dominant bacterial species of the two groups, while Flavonifractor plautii was probably a strain unique to the FAD3 group. The results suggest that the introduction of the foreign gene FAD3 has minor effects on growth performance and cecum microflora in mouse, and can increase the content of n-3 PUFAs in mouse muscle.

Key words: FAD3 gene, transgenic mouse, cecum microflora, unsaturated fatty acids