| dc.description.abstract | The objectives of the study were to assess colostrum quality and nutrients in
dairy cows in Isfahan, Iran, and to determine the effects of calving season,
parity, and volume of first colostrum on colostrum quality. Colostrum samples
were collected over the period January-December, from 365 Holstein
dairy cows from 12 dairy farms and analyzed for their IgG, IgM, total solids,
fat, protein, lactose, Ca, and P concentrations. The IgG and IgM contents were
measured to be 35.8 ± 17.6 and 5.8 ± 3.8 mg/mL, respectively. Mean percentages
of total solids, fat, protein, and lactose in the samples were 27.2 ± 5.8, 4.6
± 3.4, 18.5 ± 4.9, and 2.0 ± 0.9, respectively while calcium and P concentrations
were 2.69 ± 0.9 and 2.02 ± 0.88 g/kg. Colostral IgG and IgM concentrations
were found to be higher during the winter months. Calving season affected
lactose, Ca, and P concentrations as evidenced by the higher colostral
lactose percentages in cows calved in the fall but higher calcium and P concentrations
in those calved in the summer. Parity had no significant effects on
IgG and IgM concentrations. However, a decreasing trend was observed in Ca
and P concentrations with increasing parity. Volume of first milking colostrum
did not have any effect on colostral composition. The findings of this
study indicate that colostrum quality may be affected by calving season. | en_US |
