STUDY ON CHEMICAL AND BIOLOGICAL PARAMETERS OF COLOSTRUM IN ROMANIAN BLACK AND WHITE COWS

Abstract

The aim of the paper was to evaluate the colostrum quality and changes in
composition during the first seven days postpartum. Researches were carried out on
five Romanian Black and White multiparous cows. Samples of colostrum and
transition milk were collected at calving and at 6-hour interval for seven days.
Samples were analyzed for chemical composition using an infrared spectrometer
(fat, protein, lactose and solids non-fat), for somatic cell count using a viscosimeter,
for density using a desimeter, for total bacteria count using the classic incubation on
Petri dish, and for immunoglobulin concentration using a colostrometer. For study
the evolution of the colostrum composition Wood incomplete gamma function was
employed (y=abx
e
(-cx)). Results showed a dramatic change in colostrum yield and
composition from the first milking right after calving until the next milking occurred
at 6-hour interval. Yield was very low in the first milking (0.9 kg) and increased
rapidly with each milking, reaching 11.2 kg in the seventh day postpartum. In the
first colostrum the concentrations of milk fat, protein and total solids were high
(11.56%, 17.73% and 32.08%, respectively) and were almost half in the second
milking, after 6 hours. Lactose concentration was low at the beginning (1.89%) and
increased slowly until the seventh day postpartum to 4.39%. Density was as high as
1.74 kg/liter in the first colostrum and decreased rapidly at 1.49 kg/liter. In the
seventh day the density was 1.029 kg/liter. Immunoglobulin content had an atypical
evolution. It was low in the first colostrum (34.48 mg/ml) and the highest in the
second milking (43.66 mg/ml). After that it was decreasing until the end of
experiment. Somatic cell count and total bacteria count were high in the first milking
(1,575,488 cells/ml and 46,834 cfu/ml, respectively) and decreased after that.