Effect of lactation stage, parity and body condition on the nutritional and amino acid composition of sow colostrum and milk

Previous research showed that one out of three sows produces insufficient colostrum and milk for the offspring. This may lead to reduced piglet performance. The most obvious solution is to increase the colostrum and milk production of the sow. However, optimizing the composition of sow colostrum and milk may also be a valuable preventive measure. Therefore, knowledge of the composition of the mammary secretions and influencing factors is important. The aim of this study was to investigate the effect of lactation stage, parity and body condition (BC) on the composition of sow colostrum and milk.

Fifty sows (parity 1-10) from one commercial pig herd were observed from D0 to D10 of lactation. Colostrum and milk samples were collected at D0, D3 and D10. Nutritional composition (fat, protein, lactose, dry matter) was determined with a Fourier Transform Infrared (FTIR) milk analyzer. Amino acid (AA) were analyzed by an AA analyzer after protein hydrolysis and immunoglobulin G (IgG) by a quantitative sandwich ELISA. Back fat was measured at D0, D3 and D10. Sows were divided into 3 groups based on parity (1, 2-4, > 4) and into 3 groups based on back fat thickness at farrowing (< 13 mm, 13-16 mm, > 16 mm). Repeated measures ANOVA was used to determine the effect of lactation stage, parity and BC, and to assess interactions between lactation stage, parity and BC.

Lactation stage had a significant effect on the nutritional composition and the IgG level of colostrum and milk. This was most pronounced in the first days of lactation (D0-3) with an increase of the fat and lactose content, and a decrease of the protein content and the IgG level. Parity and BC at farrowing had no significant effect on these components. Lactation stage had a significant effect on the AA concentrations and the AA proportions (concentration of each AA / total AA concentration) of colostrum and milk. Sows with a back fat thickness of 13-16 mm showed higher concentrations of Asp, Ser, Gly, Ala, Val, Tyr, Phe, Lys and Arg. Parity had a significant effect on the AA proportions of Ser, Ala, Met, Lys, and Arg. Mainly parity 1 sows differed from the older sows.

Apart from lactation stage, the AA composition of sow colostrum and milk varies with parity and BC. As the neonatal piglet has specific AA needs, part of the effect of parity and BC on piglet performance might be due to changes in the protein quality of colostrum and milk.

Disclosure of Interest: None Declared.