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These allow for examination for surface‐living external parasites and dermatophytes where the lesions are diffuse or extensive. Scrapings are better for deeper resident mite infestations.

 Use a sterile scalp brush or new toothbrush to brush firmly over the lesions (Mackenzie brush technique; Figures 1.4a and b). Place the brush in a paper envelope to protect it prior to submission for dermatophyte culture.

 A scalp brush or wooden tongue depressor can be used to collect debris directly into a sterile Petri dish for external parasites. Material should be examined promptly as chorioptic mange mites are highly motile and easily lost from sample containers.

Figure 1.4 (a) A coarse‐toothed brush (e.g. 90 mm Denman scalp brush) facilitates sampling of large areas of skin and coat. The collected hair can be removed and examined, or the teeth may be embedded in a fungal culture medium as illustrated. (b) Here Microsporum canis has been isolated using this technique.