The number of cases of BSE in cattle this year is slightly up on last year, according to the Department of Agriculture.
The official Department figure for the total number of cases this year is 77, up three from 1996. The Department yesterday released details of December's BSE cases, which totalled seven, three down on the December 1996 figure of 11.
A Department spokeswoman said that in the second half of this year there were 40 herds infected by the disease; in the second half of 1996 there were 60 herds.
However, there is some confusion about the annual figure of 77 cases, as it does not include three cases announced in the Dail in November - and which included the discovery of a second case of BSE in the national herd at Moorepark, Fermoy, Co Cork.
Department scientists speak of the number of herds infected rather than individual animals.
If the number of individual cases is calculated, it comes to 80 and not 77.
Although the latest figures would appear to indicate a slowing down in the rate of infection, the fact that one cow with the disease is only three years old and two of the others are four years old is causing concern.
Scientists had expected the disease to be found only in older animals because of the ban on feeding bonemeal to cattle, thought to be the source of the disease, in 1990.
But contamination of cattle feed appeared to continue until January 1996, when it was decided, on EU advice, to ban compounding cattle feed at pig and poultry plants which still use meat and bonemeal.
The December cases were found in herds in Co Monaghan, Co Kerry, Co Westmeath, Co Cavan and Co Limerick.
The youngest animal, at three years, was in the Monaghan herd: the Kerry cow was six; the Westmeath cow five and the Cavan and Limerick cows were both four.
Details of two other cases were not disclosed because the farmers involved had not been informed.