Respiratory function of donkeys measured by Forced Oscillometry Technique (FOT) has not adequately been characterised. In addition, the respiratory efforts of the thorax and abdominal muscles of donkeys have not adequately been quantified. The aim of this study was to analyse the differences of thoracic and abdominal excursions during breathing by using Respiratory Ultrasound Plethysmography (RUP). Synchronisation, rhythm and relative contribution of the thoracic and abdominal muscles were analysed. Secondly, this study aimed to describe the magnitude of airway impedance (Zrs) and its two components, the airway resistance (Rrs) and the reactance (Xrs) in donkeys. Zrs, Rrs and Xrs were measured at oscillation frequencies (f) ranging from 2 Hz up to 7 Hz. Raw data was cleaned for outliers and statistically analysed. In total 18 donkeys were tested, but data of 2 animals had to be omitted entirely due to bizarre values and patterns. During the measurements, it appeared that some animals were coughing mildly and therefore post hoc the effect of coughing on group means was studied. The group mean differences of Rrs and Xrs were analysed by Mann Whitney-U test for independent samples. The RUP system in its current form is too sensitive to signal noise and generated data are difficult to quantify. Nevertheless, using an alternative algorithm the respiratory strategy of healthy and coughing donkeys appeared different. Within the oscillation frequency interval from 2 to 7 Hz, donkeys do not appear to show a clear frequency dependence of Zrs or Rrs unlike horses. However, Zrs and Rrs decreased slightly from 2 to 3 Hz, thereafter both parameters remained relatively stable. The group mean Xrs moved around 0. Not all animals showed the expected positive frequency dependent relation. It could be shown that the coughing group demonstrated Rrs compared to the healthy group, especially at the lower frequencies (f =2 to 5 Hz), whereas Xrs was significantly higher in the healthy donkeys at the higher frequencies. These findings suggest that coughing donkeys have increased respiratory resistance of the lower airways and reduced ability of the respiratory tract to store capacitive energy. The latter is associated with stiffness of the lung or with hyperinflation and loss of lung elastic recoil. The coughing was considered to be associated with mild bronchitis caused by lungworms (Dictyocaudus arnefeldii). The results of this pilot study indicate that subclinical bronchial disease of donkeys can be diagnosed using FOT. However further studies are needed to determine the optimal oscillation spectrum and improvement must be made for measuring procedures including the use of better masks before the method can be used for diagnostic purposes.
Publication(s) resulting from University thesis:
Güngör, O; Van, Den, Hoven, R
(2017): A study on observation of respiratory ultrasound plethysmography in Donkeys [Eşeklerde solunum ultrason pletismografisinin gözlemlenmesi üzerine bir çalışma].
Kafkas Universitesi Veteriner Fakultesi Dergisi 2017; 23: 797-801