Relationships Between Chemical Composition of Colostrum and Milk and Rearing Performance of Piglets During a 21-Day Lactation / Zależności Pomiędzy Składem Chemicznym Siary I Mleka A Wynikami Odchowu Prosiąt W Czasie 21-Dniowej Laktacji

Normal development of piglets is determined principally by the milking ability of the sows. This study attempted to determine the relationships between sow’s milk quality and rearing performance of the piglets. The experiment was carried out under uniform conditions, with standard feeding of the sows and a similar number of piglets per litter. The study accounted for 109 lactations of second- and third-parity Polish Large White (PLW ) sows and 123 lactations of second- and third-parity Polish Landrace (PL) sows. Colostrum and milk were collected from the sows at 1, 7, 14 and 21 days of lactation and analysed for solids, crude protein, fat, lactose and somatic cell count (SCC). Rearing performance of second- and third-litter piglets was determined based on the number and weight of piglets at birth and at 7, 14 and 21 days of age. The coefficients of correlation, estimated between basic composition of milk and rearing performance of the piglets over subsequent weeks of lactation were low and exceeded r = 0.200 only for some traits. The experiment showed that a higher content of basic milk components, in particular protein, may be one of the factors contributing to an increase in weight gain of piglets during a 21-day lactation. Milk fat content may be of significance for rearing performance of piglets only during their first week of life. Rearing performance of the piglets is unrelated to udder health expressed as milk SCC.