Abstract #M183

# M183
Post-weaning calf hepatic gene expression in response to maternal feeding with methyl donors pre-partum.
C. Bespalhok Jacometo*1, P. Montagner2, Z. Zhou3, F. Lopes4, D. Luchini5, M. Nunes Corrêa2, J. Loor3, 1Universidad de La Salle, Bogotá, DC, Colombia, 2Universidade Federal de Pelotas, Pelotas, RS, Brazil, 3University of Illinois, Urbana, IL, 4Adisseo SA, São Paulo, SP, Brasil, 5Adisseo NA, Alpharetta, GA.

The aim of this study was to assess the effect of feeding a methionine (MET) or choline (CHO) source to dams on post-weaning calf liver expression of genes related to methyl-donor pathways and energy metabolism. The experiment was conducted as a randomized complete block design with 2 × 2 factorial arrangement of MET (Smartamine M, Adisseo NA) and CHO (ReaShure, Balchem Inc.) level (with or without). Eighty Holstein calves born to cows receiving during the last ~4 wk of pregnancy MET (0.08% DMI; n = 20), CHO (60 g/d; n = 20), MIX (MET+CHO; n = 20) or control (CON; n = 20) were evaluated. Immediately after birth calves were separated from the dam, fed first colostrum within 6 h, housed individually and fed a common milk replacer twice daily. Liver biopsies were harvested (n = 8/group) at 50 d of age (~1 wk after weaning) for qPCR analysis. Data were analyzed using the MIXED procedure of SAS, with MET and CHO as a fixed effect, and also a methyl donor contrast effect was tested. Regarding methionine cycle and transsulfuration pathway, maternal feeding with methyl donors downregulated (P < 0.05) the expression of PEMT and CBS, namely due to feeding CHO, while the expression of other genes associated with this pathway (MTR, CHDH, MAT1A, MAT2A, BHMT and SAHH) were not affected by maternal diet. Maternal methyl donor feeding reduced (P < 0.05) CSAD (taurine metabolism) and GSR (glutathione metabolism) expression, while no effect was observed on CDO and GCLC expression. Additionally, MET maternal feeding downregulated (P < 0.01) GSR expression. Expression of PPARA was downregulated (P = 0.01) when the maternal diet was supplemented with methyl donors, primarily to feeding MET (P = 0.02), and GR and PCK1 tended (P = 0.08 for both) to be lower when cows were fed methyl donors. Other genes related to carbohydrate metabolism and hepatokines (SLC2A2, PC and FGF21) were not affected by maternal diet. Overall, the data suggest that maternal feeding with methyl donors during the last ~4 wk of gestation was associated with differences in calf hepatic gene expression in the post-weaning period and the response is different according to methyl donor source.

Key Words: amino acid, intrauterine nutrition, nutrigenomics