Influence of pregnancy, lactation, litter size and diet energy density on the pancreas of sows.

In a first experiment, each of 52 sows having raised one litter was randomly assigned to one of the five following groups: control (nongravid) for pregnancy (CP), 110 d pregnancy (P110), control (nongravid) for lactation (CL), 4 wk lactation with 8 (L8) and with 12 (L12) piglets. In a second experiment, each of 36 sows having raised three litters was randomly assigned to the following groups: control group (nongravid) fed a low energy density 1% tallow diet (CLED) and two lactation groups, one fed the low energy density diet (LLED) and the other fed a high energy density 10% tallow diet (LHED). At slaughter the pancreas was excised, freed from fat and weighed. Fragments were homogenized for evaluation of protein, amylase, chymotrypsin, RNA and DNA content. Pancreas weight was not affected by pregnancy, lactation or litter size. Pancreatic cellular mass (15.2%), amylase (42.6%) and chymotrypsin (34.6%) concentrations were smaller among pregnant sows (P110) than among their controls (CP). Amylase concentration tended to be lower among the L12 than among the L8 sows (P = 0.067). Sows fed the high energy diet (LHED) had greater pancreas weight (15.3) and chymotrypsin activity (48.1%) than those fed the low energy diet (LLED). Pregnancy, lactation, litter size and dietary energy density during lactation all had a significant effect on the pancreas of the sow.