COMPOSITION OF SOWS COLOSTRUM AND MILK .2. FATTY-ACID COMPOSITION, AND CONTENTS OF FAT, VITAMINS AND MACROELEMENT AND MICROELEMENTS

Total solids and fat contents, fatty acid composition, fat soluble- (A , D-3, E, K-3) and vitamin C contents, macro- and microelement content s were determined in colostrum and milk samples from 10 Danish Large W hite, 10 Danish Duroc and 10 Norwegian Landrace sows. It was establish ed that the total solids (24.03%) and fat content (5.32%) of first col ostrum increased to 48-72 h of lactation (total solids: 27%, fat conte nt: 13.1%), and afterwards decreased to 18.7% and 6.5% at the end of l actation. The fat of sow's milk contained saturated fatty acids with 4 -12 C numbers only in very low concentrations (in fact just above the limit of identification). Sow's milk contained significantly more unsa turated fatty acids than cow's milk. Particularly great differences we re found in the case of linolenic acid with sow's milk containing sign ificantly more than cow's milk. Sow's milk contained more ash (0.843%) , calcium (1965 mg kg(-1)), phosphorus (1510 mg kg(-1)), zinc (6.49 mg kg(-1)), iron (2.44 mg kg(-1)) and copper (1.34 mg kg(-1)), and less potassium (748 mg kg(-1)), sodium (387 mg kg(-1)) and magnesium (111 m g kg(-1)) than cow's milk, while there were no differences between the two species in manganese content. Potassium, sodium, iron and copper contents decreased, while calcium and phosphorus contents increased du ring lactation. Contents of vitamins A, D-3, E, K-3 and C of colostrum (1.61, 0.015, 3.69, 0.092 and 68.4 mg kg(-1)) were found, with the ex ception of vitamin K-3, to be one and a half to twice as great as that of late lactation milk (0.92, 0.009, 2.53, 0.089 and 45.3 mg kg(-1)). Sow's milk contained vitamins at two to three times the concentration s in cow's milk. There were no significant differences among breeds or interaction between breeds and time of sampling with regard to compos ition of colostrum and milk.