SAO PAULO, May 21 (Reuters) - Brazil's state of

Tocantins has ruled out the occurrence of highly pathogenic

avian influenza, known as bird flu, in a local commercial farm

citing preliminary test results, according to a statement sent

to Reuters on Wednesday.

Adapec, as the state's farm agency is known, said

authorities started the investigation on a local commercial

chicken farm after seven animals, out of about 40,000

individuals, presented "torticollis", the statement said.