Reviewing the palaeopathological evidence for bovine tuberculosis in the associated bone groups at Wetwang Slack, East Yorkshire

The excavations by T. C. M Brewster and J. S. Dent between 1964 and 1989 at the multiperiod site at Wetwang Slack, East Yorkshire, has gained international importance for its square barrow cemetery and multiple Arras-style Iron Age cart/chariot burials. A lesser known fact is that the excavations also produced the largest Iron Age faunal assemblage identified outside of southern Britain, in addition to several late Iron Age/early Romano-British articulated animal bone groups (ABGs). The presence of pathological human and articulated faunal remains provides the unique opportunity to review the macroscopic evidence for zoonotic diseases, specifically bovine tuberculosis (bTB) in an Iron Age community where close working relationships with animals, the use of animal by-products, and the consumption of infected dairy products all form potential avenues of infection. This paper presents the palaeopathological evidence for possible infectious disease in the ABGs at Wetwang Slack with a focus on bTB. Several cases of suspected tuberculosis are described in the human remains, with one example of gastrointestinal infection that could potentially indicate a case of bTB. Ancient DNA (aDNA) samples were taken from five ABGs testing for both Mycobacterium tuberculosis complex and Brucella pathogen DNA. The results were negative, but DNA degradation was highlighted as a contributing factor. This paper highlights the importance of considering the evidence for zoonotic diseases at sites where human and faunal assemblages are recovered and especially where articulated animal skeletons are present. The paper also emphasizes that future aDNA studies of diseased faunal remains should focus on smaller amplicons or whole genome sequencing to amplify pathogen DNA.