Japanese scientists have launched an investigation into a possible new strain of BSE after a bullock was diagnosed as having the disease. Confirmation of a new strain would be a setback for Japan’s cattle and beef industries which have struggled to regain public confidence after the first case of BSE was discovered in Japan two years ago.

The case differs from previous incidents of BSE because tests on the animal show that the prions, a self-replicating protein said to cause the disease, were arranged in different patterns from past cases. It also differs from previous cases because it involves a male animal.

In addition, the bullock was only 23 months old, making it the second youngest animal to have contracted the disease. The animal, a Holstein, was born in the Tochigi Prefecture in October 2001 before being raised in the Fukushima Prefecture from May 2002. The animal was slaughtered in the Ibaraki Prefecture.

The bullock was born one month after Japan banned the use of meat and bone meal which is regarded as the main route if infection. It is Japan’s eighth recorded case of BSE. The discovery of BSE in an animal of only 23 months is cause for widespread concern. In the UK, where BSE was first discovered in 1986, tests are performed only on animals of 24 months or older.