There was a 34% increase in bovine deaths on Irish farms in April 2013 compared the same month last year.
Figures show that 42,792 animals died in April, up from 31,739 last year.
Cattle deaths for the first four months of 2013 were up by 35% on the previous year at 157,000 - the highest on-farm death rate since 2008.
The increase follows the severe fodder crisis experienced across the country that started with last summer’s bad weather.
In a statement, Minister for Agriculture Simon Coveney said mortality rates fluctuate from year to year due to disease and environmental factors including weather and fodder related issues.