Livestock is a primary source of income for small dairy farmers in developing countries. Dairy animals fed with a fodder containing a balanced nitrogen contents produce high quality milk. Excess use of nitrogen fertilizers in the soil cause excess accumulation of nitrates in fodder, which is the main source of nitrate poisoning in dairy animals. In the present study nitrate contents in fodder crops, viz., Sorghum bicolor (Jowar), Pennisetum glaucum (Bajra), Zea mays (Makai), Avena sativa (Jai), Brassica rapa (Shaljam) and Brassica Campestris (Sarson) were estimated twice a day i.e. early morning and afternoon. The fodder samples were collected from different villages of Okara, Pattoki and Ravi areas of the Province Punjab. Nitrate contents of different parts of the fodder plants were estimated qualitatively through the Diphenylamine Filed Test (DFT) and quantitatively by spectrophotometry. The nitrate levels were highest in Jowar, followed by Jai, Shaljam, Makai, Bajra and Sarson. The concentrations were lower in the afternoon in the leaves and in mature crops as compared to stem parts, immature plants, and in samples collected from plants during morning hours. The nitrate concentration was lower in samples collected from Ravi area, as compared to samples collected from villages of Pattoki and Okara. Blood samples were collected from animals feeding on above fodders; Spectrophotometry analysis of blood samples from these animals showed abnormally high levels of nitrite. In conclusion, nitrate contents were higher (>5000 ppm) in stem parts of common livestock fodder harvested in early morning and therefore, high level of nitrite found in blood of animals fed with the fodder containing high nitrate contents. This high level of nitrates in fodder crops constitutes a threat to the health and productivity of dairy animals.