Test results on a dog suspected of dying from toxic poisoning in Lough Ree are expected by Westmeath County Council's chief veterinary officer, Mr Sean O'Laoide, later this week.
The dog was one of two which died in separate incidents at Portlick on the eastern side of the lake, and Barrymore on the western side, in the past 10 days. Tests on the first dog, described by Mr O'Laoide as "a classic case" of poisoning from an algal bloom, were not conclusive.
The news is a setback for the campaign group Save Our Lough Ree (SOLR) which represents users and business interests in the area which spans Roscommon, Longford and Westmeath.
It was hoped that a new treatment plant in Roscommon would improve the quality of the river Hind, a feeder to Lough Ree, while reductions in the use of phosphate-based fertiliser would also help.
Last year a locum vet lost three of her five dogs after they went in the water during a lakeside walk, and locals fear similar incidents this year may have a catastrophic effect on tourism. "We don't yet know what the effect of the new treatment plants on the water is", said Mr Michael Ganley of SOLR, "but we are hoping it is good".
Mr Ganley said, however, that the death of two dogs, both privately owned pets, at separate locations was a bad indicator. "It is normally July or August when the water warms up, and there is no movement in the sheltered bays where the bloom occurs. This year it seems to have happened early," he said.
The members of SOLR are concerned that factors in the Lough Ree catchment area, from industries to agriculture to waste water, make it hard to ascertain what is causing the problem.
The incidence is also of concern to Mr O'Laoide, who told The Irish Times that it could be 10 years before the water has improved sufficiently to be safe for animals.
He said people could suffer from nausea, headaches, vomiting and soreness and he expected the local authorities in the area to put up signs warning people not to bathe in the lake.
"Even if the quality of the water is improving I would expect the algal blooms to go on for maybe as long as the next decade," Mr O'Laoide said.
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