Effects of teat position on selected milk components of primiparous sows during lactation

The composition of sow colostrum and milk from single teats were characterized in 20 primiparous German Landrace sows at ten points throughout lactation time (after birth of the first piglet, and subsequently at 12 and 24 h, 3, 5, 7, 14, 21, 28 and 35 d postpartum). In these samples contents of protein, IgG, lactose and fat were analyzed. In the first 3 days of lactation protein- and IgG-contents drastically decreased, on the other hand the levels of energy resources lactose and fat increased. Significant effects of the single teat and the teat pair on the content of protein at farrowing and 12 h later as well as on the contents of IgG and lactose 12 h postpartum were found. The highest contents of protein and IgG were analyzed in colostrum of teats in the median udder section, the colostrum of cranial teats had the highest content of lactose. At days 3 and 5 of lactation milk showed large coefficients of variation (cv) in milk composition from teat to teat as well as from sow to sow (intraindividual cv: protein: 22%, IgG: 45%, lactose: 20%, fat: 34%; interindividual cv: protein: 36%, IgG: 85%, lactose: 27%, fat: 47%). During lactation period the intraindividual variation of milk parameters was lower than the interindividual variation. Possible reasons for these results are discussed.