Urea is a legitimate and economical source of non-protein nitrogen for ruminants, but the same compound turns into a serious hazard when it reaches dairy animals in the wrong amount, in the wrong form or at the wrong time. In India, which produced 247.87 million tonnes of milk in 2024-25 (DAHD, 2025), urea contamination of feed arises mainly from deliberate spraying of costly oilseed cakes to increase their apparent protein, from uneven mixing in compounded feed, and from careless storage of fertiliser urea on farms. In the rumen, urea is split into ammonia far faster than microbes can use it and the surplus can take over the liver within an hour. This article brings together the permissible level (1.0 percent of compounded cattle feed under IS 2052:2023), the toxic and lethal doses (0.3 to 0.5 and 1.0 to 1.5 g per kg body weight), the clinical picture, first-response steps, and a practical prevention plan that suits smallholder and commercial dairies. The priorities for quicker field testing, improved regulations and research on Indian cattle and buffaloes are highlighted in this article.