Trace micro-nutrients may affect susceptibility to bovine tuberculosis in cattle

Area of Science:

• Veterinary Immunology
• Animal Nutrition
• Infectious Diseases

Background:

• Bovine tuberculosis (bTB) poses a significant challenge in British cattle herds.
• Micronutrients play a crucial role in maintaining a robust immune system in cattle.
• Understanding the relationship between specific micronutrients and bTB susceptibility is vital for herd health management.

Purpose of the Study:

• To investigate the association between the status of selenium, copper, and vitamin B12 in cattle and Mycobacterium bovis (M. bovis) infection.
• To determine if blood levels of glutathione peroxidase (GSHPx), copper, and vitamin B12 correlate with bTB infection in cattle.

Main Methods:

• Blood samples were collected from 200 tuberculin reactors and 200 in-contact cattle in England and Wales (2002-2005).
• Measurements included blood levels of GSHPx, copper, and vitamin B12; liver selenium and copper were also analyzed in a subset.
• bTB infection was confirmed through bacteriological culture and histopathology postmortem.

Main Results:

• Lower blood GSHPx levels were significantly associated with confirmed bTB (p<0.01).
• Higher blood copper levels showed an increased risk of confirmed bTB (adjusted OR 1.69, p<0.01).
• Lower liver copper levels were also linked to a higher risk of confirmed bTB (adjusted OR 0.15, p=0.05). Vitamin B12 and liver selenium showed no significant association.

Conclusions:

• Micronutrient status, particularly lower GSHPx and higher copper, may influence cattle susceptibility to M. bovis infection.
• These findings suggest a potential role for nutritional interventions in managing bTB risk in cattle herds.
• Further research is warranted to elucidate the precise mechanisms and explore practical applications.