Bracken (Pteridium aquilinum)

calendar icon 3 December 2018
clock icon 2 minute read

Bracken produces a toxin that destroys the vitamin thiamine. Pigs are normally resistant to bracken poisoning and it needs in excess of six weeks of constant exposure particularly to fresh bracken shoots and the rhizomes.

Clinical signs

Sudden death is often the only sign, although prior to this respiratory distress may be seen associated with oedema or fluid in the lungs.


This is based on history, clinical signs if seen and enzyme tests carried out on serum.

Treatment and control

  • If sows are likely to have access to large amounts of bracken, injections of thiamine should be given every two weeks. Where clinical signs are seen all the group at risk should be injected with thiamine.

Emily Houghton

Editor, The Pig Site

Emily Houghton is a Zoology graduate from Cardiff University and was the editor of The Pig Site from October 2017 to May 2020. Emily has worked in livestock husbandry, and has written, conducted and assisted with research projects regarding the synthesis of welfare and productivity of free-range food species.

More Disease guide

View all

Porcine Circovirus (PCV1/PCV2/PCV3) (PCVAD)

calendar icon 6 May 2022
clock icon 1 minute read


calendar icon 4 December 2018
clock icon 1 minute read


calendar icon 3 December 2018
clock icon 1 minute read
© 2000 - 2023 - Global Ag Media. All Rights Reserved | No part of this site may be reproduced without permission.