The incident occurred on September 21 when over 180 goats were killed
Nitrate containing water went into the rumen of the animals
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/death-goats-due-consumption-nitrate-dissolved-water-tnpcb
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/hindu-chennai
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-pollution
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/cattle
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/state-pollution-control-board-spcb-0
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/tamil-nadu
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/tiruppur