Fig. 2: Father companionship changed the serum metabolomic profile of male offspring.

a Expression abundance of quality control for samples. b OPLS-DA plot between the father companionship and control group. c Volcano plot showing the differential metabolites between groups. d Bubble diagram of the KEGG enrichment pathway for significantly regulated differential metabolites. e The Lollipop map shows differences in up-regulated and down-regulated metabolites in the father companionship group compared with the control group. f The abundance of L-aspartic acid was elevated in the father’s companionship group compared to the control group (t₍₁₀₎ = 4.380, P = 0.001, t test). n = 6 per group. g The abundance of 3-sulfinoalanine was reduced in the father’s companionship group compared to the control group (t₍₁₀₎ = 9.374, P < 0.001, t test). n = 6 per group. h–j Correlation between the abundance of L-aspartic acid and defensive attack behavior. L-aspartic acid was positively associated with the frequency of biting (r = 0.706, P = 0.013). k–m Correlation between the abundance of 3-sulfinoalanine and defensive attack behavior. 3-sulfinoalanine was negatively associated with the frequency of biting (r = –0.617, P = 0.037). n = 12 (6 in the intervention group and 6 in the control group). FC father companionship, KSAHI Kaposi sarcoma-associated herpesvirus infection. PAC-DAP (2-Phenylacetyl) (2 R)-2,5-diaminopentanoate. * P < 0.05; **P  < 0.01; ***P < 0.001.