EN
A dry extract from the bark of Uncaria tomentosa was evaluated as a potential immunomodulator in various formulations. Hens were immunised three times orally with a bovine serum albumin (BSA) supplemented with 7, 70, and 280 mg of the dry extract of the bark. Specific IgA antibodies in saliva and IgY antibodies in yolk were examined by ELISA. It was found that the birds inoculated with BSA in addition to 280 mg of Uncaria tomentosa bark extract had a higher amount of BSA-specific IgA antibodies in the saliva and BSA-specific IgY antibodies in yolk, than hens that received lower doses of the extract. Furthermore, the hens immunised with BSA alone had significantly lower immune responses to BSA than hens immunised with BSA supplemented with the bark extract. These results suggest that dry extract from bark of Uncaria tomentosa is useful as an oral adjuvant or immunomodulator for hens.