Pine processionary development, pine processionary caterpillars are highly irritating to the skin. Contact with the hairs of the caterpillar can cause severe rashes (urticaria) and eye irritation. Some individuals may have an allergic reaction to the caterpillar's hairs. 5th stage larvae can eject hairs when threatened or stressed; the hairs, which have the form of harpoons, then penetrate and irritate all areas of exposed skin nearby with an urticating protein. Allergic reactions may follow in susceptible individuals on subsequent exposure to the hairs. The pine processionary is an economic pest in coniferous forests in southern Europe. It is controlled to some extent
Animal Health Trust internship and residency training programmes. The Continuous Professional Development (CPD) programme has also expanded in recent years. The AHT publishes papers detailing its research and clinical findings in journals and online, for the veterinary and science professions. It also has its own open-access library. Housing journals, publications and findings, it is available for use by anyone studying animal health. The Animal Health Trust’s veterinary clinics provide referral services to small animal and equine veterinary practitioners. It has two clinical centres: the Centre for Small Animal Studies and Centre for Equine Studies. It also offers diagnostic laboratories and DNA testing services.