Development of facial masks for indirect calorimetric studies for livestock

Abstract

With the use of a facial mask, it is possible to evaluate the gaseous exchange of an animal outdoors. But the question is: can an animal put on a facial mask for a long period of time without affecting its physiological responses? To answer this question, our research developed facial masks for different livestock species. The objectives were to design and built facial masks and to determine the effect of using a mask on the physiological responses of animals. Facial mask for poultry, sheep, goat and cattle were developed. In order to determine the effect of wearing a mask for a long period of time on the physiological responses of animals, we performed experiments and collected respiratory rates from different species of animals. We measured respiratory rates before and after putting the facial mask on the animal's muzzle for one hour at regular intervals of ten minutes (time: 0, 10, 20, 30, 40, 50 and 60). The respiratory rate at time zero was measured without using a mask. The facial masks developed for cattle and goats did not affect the respiratory-rate measurements during the 60-minute experimental period, but did for sheep. Therefore, in sheep, the mask must be used after the animal adapts to it. For poultry, a hood is more appropriate than a mask to avoid discomfort and leakage of air.