pressure

Different harness systems were tested (collars and pack saddles), controlling variables that can influence the results, such as draft work when performing different tasks, load displaced, balance of the load, etc.

Phase one:

Seven different collars were tested using pressure pads. Contact area, median, maximum and peak pressures were obtained for the whole collar and critical points. Eight donkeys pulled 20% and 40% of their body weight, using each collar, under controlled conditions.

This phase was mainly focused on the use of pressure pads, determining the force and pressure distribution beneath different harnessing and packing systems in 8 working donkeys (both static and dynamic tests).

Preliminary trials were performed, using a load cell coupling system (dynamometer), fitted between the equipment used, and the animal. Other preliminary tests included the evaluation of workload effort based on physiological parameters (heart rate using a Holter system), with the main purpose of obtaining more reliable parameters for equids’ performance and welfare; and the use of thermal camera to monitor and evaluate all the contact areas of the harnesses used in this project.

Phase two:

Based on the very promising results obtained during the preliminary trials of the first phase of this project; the researchers moved to the second phase. Controlled, real working operations (logging and agriculture) were performed with working donkeys to a) evaluate the three different collars, b) measure the force exerted by the equids using a swingletree dynamometer and c) evaluate the workload effort based on physiological parameters.