Changes made by 91/643/EEC: Commission Decision of 22 November 1991 establishing a list of semen collection centres in the United States of America approved for the export to the Community of deep-frozen semen of domestic animals of the bovine species
EU Decision 1991/643
No changes made by 91/643/EEC: Commission Decision of 22 November 1991 establishing a list of semen collection centres in the United States of America approved for the export to the Community of deep-frozen semen of domestic animals of the bovine species are recorded.
From legislation.gov.uk's record of changes, the official one: see it there.