Domestic milk intake by creameries and pasteurisers was estimated at 775.5m litres for April 2015, according to the CSO.
It says this was 14.5% above the corresponding 2014 figure.
Increased milk production last month comes on the back of the ICBF showing that dairy calf registrations are running 10% ahead of last year.
To date some 1,066,544 dairy-bred calves have been registered with the ICBF. This compares to 970,000 at the same stage last year.
The figures mean some 96,000 extra calves have been registered by dairy farmers this year.
Comparing the April 2015 milk produce figures with those for April 2014 also shows that total milk sold for human consumption decreased by 1.9% to 36.2m litres. Meanwhile butter production was up 15.3% to 19,900t.
Despite high supplies so far this season the IFA says there are still reasons for co-ops to hold May milk prices.
IFA National Dairy Committee Chairman Sean O’Leary has said that recent reports from France Agrimer and Germany’s ZMB suggest that milk supplies for the January to mid-May period were significantly below last year’s level, by 2.45% for France and 2% for Germany.
He said that as those two countries alone account for over 40% of all milk produced in Europe, this is an important indication that the expected ‘wall of milk’ in post-quota Europe had yet to materialise.
He added that with major droughts in California and an El Nino event declared for Australia that could also affect New Zealand supplies, the global supply/demand balance could tip over sooner rather than later.
He urged co-ops to bear this in mind, and to continue to support milk prices at least for May milk.