title: Validation of pressure measurements and electromyographic results for the uterus of cattle during the early postpartum period.
abstract: OBJECTIVE
  To evaluate methods for on-farm measurements of uterine contractility in postpartum dairy cows by comparing data simultaneously recorded by use of 2 intrauterine pressure (IUP) devices and quantified electromyographic (EMG) signals.
  
  
  METHODS
  5 cows during the first 48 hours after parturition.
  
  
  METHODS
  2 EMG electrodes were implanted on the surface of the gravid uterine horn. Parturition was induced by injection of a prostaglandin F2alpha analogue at day 274 of gestation. An open-tip catheter and pressure microtransducer were transcervically inserted and affixed to a caruncle immediately after calving. Changes in IUP were recorded concurrent with EMG recordings during 2-hour periods at 2, 6, 12, 18, 24, 36, and 48 hours after parturition. Novel acquisition and analysis software programs were used with a digital data-filtering capability for evaluation of IUP and EMG signals.
  
  
  RESULTS
  The method for intrauterine fixation of the 2 pressure measurement instruments was effective and allowed easy, externally guided removal of the devices 48 hours after parturition. There was a high correlation between the data obtained by the 2 pressure measuring systems. Good correlation was also found between pressure data obtained by the open-tip catheter system and EMG signals. Although the quantified IUP and EMG signals were highly comparable, synchronization was not always evident during visual inspection of these signals.
  
  
  CONCLUSIONS
  The open-tip IUP catheter system with a special fixation method is suitable for use in on-farm studies. It will enable investigators to record natural and pharmacologically influenced uterine contractility in early postpartum dairy cows.
authors.affiliation: Department of Farm Animal Health , Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, Yalelaan 1-7, The Netherlands.
authors.forename: Arpád Csaba
authors.initials: AC
authors.lastname: Bajcsy
authors.forename: Gijsbert C
authors.initials: GC
authors.lastname: van der Weijden
authors.forename: Arie
authors.initials: A
authors.lastname: Doornenbal
authors.forename: Vidya N A
authors.initials: VN
authors.lastname: Breeveld-Dwarkasing
authors.forename: Rineke C
authors.initials: RC
authors.lastname: de Jong
authors.forename: Ottó
authors.initials: O
authors.lastname: Szenci
authors.forename: Marcel A M
authors.initials: MA
authors.lastname: Taverne
mesh_terms: D000818:Animals; D002404:Catheterization / Q000379:methods / Q000662:veterinary; D002417:Cattle / Q000502:physiology*; D004576:Electromyography / Q000662:veterinary; D005260:Female; D009119:Muscle Contraction / Q000502:physiology*; D049590:Postpartum Period / Q000502:physiology*; D011312:Pressure; D014599:Uterus / Q000502:physiology*