Proliferation and differentiation of stromal-vascular cells in primary culture differ between neonatal pigs consuming maternal or formula milk

Proliferation and differentiation of preadipocytes from 7-d-old pigs consum ing maternal or formula milk were examined in primary culture of stromal-va scular (s-v) cells derived from subcutaneous adipose tissue. Unsuckled pigs were bottle-fed isoenergetically with colostrum and then sow's milk (SM) o r with formula milk alone (F) from birth to 7 d. Isolated cells were expose d to serum-supplemented medium and serum-free medium to determine prolifera tion and differentiation, respectively, proliferation estimated between d 3 and 4 of culture was higher (P < 0.05) in cells from F than SM pigs, In ad dition, the number of s-v cells isolated from 1 g of adipose tissue was hig her (P < 0.01) in F than SM pigs, Variables assessing differentiation were also affected, The percentage of differentiating cells and lipoprotein lipa se (LPL) activity were lower (P < 0.05) in F than SM pigs, whereas malic en zyme (ME) activity did not differ significantly between the two groups. In conclusion, formula milk increased the number of s-v cells and their capaci ty for proliferation, whereas the potential for cell differentiation was lo wer compared with cells from the maternal milk group, Further studies are r equired to identify the growth and/or nutritional factors that are implicat ed in the observed differences and to determine whether subsequent developm ent of adipose tissue is affected.