Diagnostic tests for some conditions affecting cattle, such as tuberculosis, are often expensive and required over a prolonged period, so that the diagnostic tests involve more than one visit by a qualified vet. An alternative rapid and non-invasive diagnostic-test would be desirable. One possibility is the use of breath testing, which has been shown to have diagnostic potential in humans. The development of a device for taking a representative breath sample from a bovine animal is described. Six devices using different configurations were assessed, over three separate testing days, for their ability to take a representative breath sample which does not cause undue stress to the animal and for the ease of operator use. The main factor affecting the sample integrity was dead space, however temperature also played a role. The best samples causing the least stress to animals were taken using a nostril sampler. The nostril samplers were then used to take breath samples from cattle with and without tuberculosis which were then analysed using selected ion flow tube mass spectrometry and gas chromatography-mass spectrometry to demonstrate proof-of-principle. (c) 2012 IAgrE. Published by Elsevier Ltd. All rights reserved.