and the presence of orotic acid and amygdalin, which have been attributed with antineoplastic properties, sheep milk has dietetic and curative properties ...
Arch. Tierz., Dummerstorf 47 (2004) Special Issue, 129-134 Department of Sheep and Goat Breeding, Agricultural University of Krakow1, 2Department of Animal Products Processing, Agricultural University of Krakow
STEFAN CIURYK, EDYTA MOLIK , URSZULA KACZOR and GENOWEFA BONCZAR2
Chemical composition of colostrum and milk of Polish Merino sheep lambing at different times Abstract Chemical composition and fatty acid content of colostrum and milk were analysed in Polish Merino sheep lambing at different times. The sheep lambed in January and June, and were keep indoors throughout the experiment. It was found that the content of different components in colostrum and milk of sheep in both groups was comparable with the results obtained by other authors. Slight differences in the content of fat and fatty acids were probably due to lower milk yield of the sheep, whose lactation took place under a decreasing light day. Key Words: sheep, milk, colostrum, chemical composition, fatty acids profile
Zusammenfassung Titel der Arbeit: Chemische Zusammensetzung von Kolostrum und Milch der zu unterschiedlichen Zeiten ablammenden Polnischen Merinos Es wurden die chemische Zusammensetzung und das Fettsäurenmuster des Kolostrum und der Milch von zu unterschiedlichen Terminen ablammenden Mutterschafen des Polnischen Merinos untersucht. Die Schafe wurden ganzjährig im Stall gehalten und lammten im Januar und Juni ab. Die Zusammensetzung des Kolostrums und der Milch der Schafe aus unterschiedlichen Untersuchungsgruppen stimmten mit Literaturangaben überein. Kleine Unterschiede im Fettgehalt und Fettsäurenmuster sind wahrscheinlich auf die niedrigeren Milchleistungen der Schafe, die die Laktation bei verkürztem Tageslicht erlebten, zurückzuführen. Schlüsselwörter: Schafe, Milch, Kolostrum, chemische Zusammensetzung, Fettsäurenmuster
Introduction Raising sheep for milk is an alternative way of improving the profitability of sheep farming in Poland. In the European Union countries, no limits have been set on the production of sheep milk. With time, this may help to increase the interest in dairy use of sheep. The nutritive value and technological suitability of sheep milk resulting from its chemical composition have been highly appreciated for centuries. Compared to cow’s milk, sheep milk is almost twice higher in fat and protein (BONCZAR et al., 1999; DROŻDŻ, 1985). Thanks to the greater content of vitamins than in cow’s milk and the presence of orotic acid and amygdalin, which have been attributed with antineoplastic properties, sheep milk has dietetic and curative properties (BORYS, 2001). The rich composition of sheep milk determines its nutritive value and technological suitability, which should earn it a better position among animal-origin products than previously. The growing interest in the consumption of sheep milk products may help to increase the population of sheep in Poland. The primary function of the mammary gland in ruminants is to provide neonates with full-value food along with immune substances. This function is fulfilled by colostrum, a special secretion produced late in gestation and on the first days after parturition. Composition of colostrum is species related and has been observed to change within several hours of parturition (GORBAN et al., 2001; PATKOWSKA, 2001). Raising of sheep for meat, a practice that has been developed for many years in Poland, compels breeders to ensure continued supplies of live lambs. One way of satisfying the market needs is to
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apply different dates of lambing. Polish Merino is a breed that meets these requirements. Shortening the rearing period of lambs with mothers makes it possible to use them for milk. The objective of the present study was to determine the chemical composition of colostrum and milk obtained from sheep lambing on two different dates. Material and Methods The studies were carried out at the Experimental Station of the Department of Sheep and Goat Breeding, the Agricultural University in Krakow. Forty sheep in their third and fourth lactations were selected from a flock of 40 sheep. The sheep were assigned to two groups of 20. The first group, after previous synchronization of oestrus with the “Chronogest” method, were mated on 23-25 August. Lambing took place in the last decade of January. The second group was also synchronized with the Chronogest method and mated in the last decade of January, with lambing in the third decade of June. Lambs were reared with their mothers to 56 days of age and weaned, and mothers were designated for milking. Sheep were milked twice a day with an AlfaLaval milking machine until drying off. Until the end of the 4th month of gestation, sheep were fed traditionally (Normy żywienia, IZ 1998), and from the fifth month of gestation until drying off, mothers were kept indoors and fed with a pelleted diet (8.5 MJ net energy and 220 g CP) at 1.5 kg/day/sheep, and a hay supplement ad libitum. After lambing, colostrum samples were taken from the sheep at 1, 3, 6, 12, 24, 48 and 72 hours and bulk milk samples were collected from the first three months of lactation. Table 1 Chemical composition of colostrum of Polish Merino sheep ( x and SD) (Chemische Zusammensetzung der Kolostralmilch der Polnischen Merinos) Hours of lactation Lambing time Fat Protein Dry matter (%) (%) (%) 1 I 11.1A ± 3.4 21.2A ± 2.9 32.2A ± 4.8 II 10.2A ± 3.5 22.2A ± 2.1 33.4A ± 4.1 3 I 13.5B ± 3.5 15.3B ± 4.1 25.0B ± 4.7 II 16.3B ± 3.8 15.2B ± 3.8 26.5B ± 3.8 6 I 13.9B ± 3.8 13.9B ± 2.9 23.9B ± 4.2 II 14.3B ± 4.1 14.0B ± 3.2 24.9B ± 3.2 12 I 10.8A ± 3.5 6.6C ± 2.1 15.9C ± 1.9 II 9.3A ± 3.9 6.7C ± 2.3 16.2C ± 2.5 24 I 7.3C ± 3.2 6.6C ± 1.9 15.5C ± 1.8 II 8.5C ± 0.8 6.8C ± 2.1 15.5C ± 1.8 48 I 6.8CD ± 2.8 6.7C ± 1.8 13.8C ± 2.2 II 7.8C ± 1.1 6.9C ± 1.4 14.0C ± 2.0 72 I 6.6D ± 2.0 6.0C ± 1.3 16.8C ± 2.8 II 6.5D ± 2.5 6.2C ± 1.1 16.9C ± 2.3 A,B, C,D (a, b, c, d)– means within groups with different capital (small) letters differ P
