title: Mass spectral analysis of urine proteomic profiles of dairy cows suffering from clinical ketosis.
abstract: BACKGROUND
  Ketosis is an important metabolic disorder in dairy cows during the transition period. The urine proteomics of ketosis has not been investigated using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS).
  
  
  OBJECTIVE
  The aim is to determine differences between urine proteomic profiles of healthy cows and those with clinical ketosis, and facilitate studies of the underlying physiological and biochemical mechanisms that lead to liver pathology in ketosis.
  
  
  METHODS
  We analyzed the urine samples of 20 cows with clinical ketosis (group 1) and 20 control cows (group 2) using SELDI-TOF-MS.
  
  
  RESULTS
  Thirty-nine peptide peaks differed between both groups. Polypeptides corresponding to 26 of these differential peptide peaks were identified using the SWISS-PROT protein database. We found that the peaks of 11 distinct polypeptides from the urine samples of the ketosis group were significantly reduced, compared with those of the control group as based on the Wilcoxon rank sum test. Among these were VGF (non-acronymic) protein, amyloid precursor protein, serum amyloid A (SAA), fibrinogen, C1INH, apolipoprotein C-III, cystatin C, transthyretin, hepcidin, human neutrophil peptides, and osteopontin.
  
  
  CONCLUSIONS
  These proteins may represent novel biomarkers of the metabolic changes that occur in dairy cows with ketosis. Our results will help to better understand the physiological changes and pathogenesis observed in cows with ketosis.
  
  
  CONCLUSIONS
  The SELDI-TOF-MS can be used to understand the physiological and biochemical mechanisms of ketosis and identify biomarkers of the disease.
authors.affiliation: a Department of Veterinary Medicine, College of Animal Science and Veterinary Medicine , Heilongjiang Bayi Agricultural University , Daqing 163319 , China.
authors.forename: Chuang
authors.initials: C
authors.lastname: Xu
authors.forename: Shi
authors.initials: S
authors.lastname: Shu
authors.forename: Cheng
authors.initials: C
authors.lastname: Xia
authors.forename: Pengxian
authors.initials: P
authors.lastname: Wang
authors.forename: Yuhang
authors.initials: Y
authors.lastname: Sun
authors.forename: Chuchu
authors.initials: C
authors.lastname: Xu
authors.forename: Changsheng
authors.initials: C
authors.lastname: Li
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000652:urine*; D002417:Cattle; D002418:Cattle Diseases / Q000652:urine*; D003612:Dairying; D003663:Decision Trees; D005260:Female; D007662:Ketosis / Q000652:urine / Q000662:veterinary*; D013058:Mass Spectrometry / Q000662:veterinary; D010455:Peptides / Q000652:urine; D025341:Principal Component Analysis; D014556:Urine
chemical_list: D015415:Biomarkers; D010455:Peptides
keywords: SELDI-TOF-MS; bovine; dairy cow; ketosis; proteomics; urine