NORBROOK Laboratories, which is owned by Senator Edward Haughey, has signed the largest single contract in the company's history, worth more than $33 million (£19.6 million).

It will supply sterile antibiotics to one of the world's largest veterinary pharmaceutical companies.

The name of the US multi-national is not being revealed for "reasons of commercial confidentiality". The contract is for 80 million cattle treatments of selected antibiotics to treat infections in dairy cows.

Mr Alan Patterson, managing director of Norbrook, said a multi-million pound capital investment at the company over two years ago had provided it with the facility and capacity to compete for and win such a lucrative contract.

A good workforce and a heavy investment in research and development had also contributed to the company's success, he added.