Lactose-rich milk replacer modifies the proteome of bloodplasma in 2-week-old calves

Abstract

The aim of the study was to create a specific pattern of protein expression changes in the plasma of 2-week-old calves treated with excessive lactose doses. Identification of proteins, the expression of which changes during the short-term administration of lactose, may help to exclude or confirm the causes of diarrhea observed in newborn calves. The present study utilized 2-D electrophoresis combined with MALDI-TOF mass spectrometry and identified 6 blood plasma proteins, the expression of which changed under the influence of lactose added to the milk replacer. The pattern of expression of blood plasma proteins, including decreased expression of fibrinogen and apolipoprotein A-IV and increased expression of alpha-1B-glycoprotein, alpha-1-antiproteinase, and apolipoprotein E in 2-week-old calves fed with lactose-rich milk replacer, can be used to determine the causes of diarrhea in calves.

Excessive amount of lactose in the diet of two-week-old calves induces urinary protein changes

“…It may be hypothesised that the lactose oversupply was the main factor that influenced the abundance level of the two proteins (sex hormone-binding globulin and cytochrome P450 2E1), and the diarrhea may be the reason responsible for the observed alterations in the abundance of the remaining three proteins (alpha-1-antiproteinase, serotransferrin and ATP-citrate synthase). The results of the present and previous studies clearly indicate that excessive amount of lactose in a diet of calves induces changes not only in blood plasma proteins (Dratwa-Chałupnik et al, 2016a) but also in urinary proteins.…”

“…The calves studied that did not have access to water were fed only with milk replacer formulation twice a day. The values of blood plasma glucose concentration increased from 4.27 mmol L −1 (before lactose administration) to 4.08 mmol L −1 (after lactose administration); however, these changes were not significantly relevant (Dratwa-Chałupnik et al, 2016a). The increased supply of glucose (derived from the lactose breakdown), as in the previously described experiment (Kim et al, 2006), was most likely the cause of decreased abundance of CYP2E1 in the urine of calves.…”

“…Blood plasma concentration of potassium was analysed using inductively coupled plasma optical emission spectrometry (ICP-OES) with a 2000 DV spectrometer (Perkin Elmer Inc) -the results are presented in the study of Dratwa-Chał upnik et al (2016b). The blood glucose level was determined spectrophotometrically (Power-Wave Xa, Bio Tek)the results were previously published in the study of Dratwa-Chałupnik et al (2016a).…”

“…The results of this study can indicate that an increased supply of lactose disaccharide may also reduce the synthesis of SHBG; consequently, removal of this protein in the urine is reduced. Only a slight increase in plasma glucose level was observed in calves 12 h after the second dose of lactose administration (Dratwa-Chałupnik et al, 2016a).…”