The effectiveness of endozoochory and germination success of the weeds after passage through the animal gut are the important traits for dissemination and invasion of weeds. With this view, experiments were conducted during the Rabi season of 2017-18 and 2018-19 at ICAR-Indian Veterinary Research Institute (IVRI), Izatnagar Campus with the objective to assess the effect of endozoochorous dissemination of weed (Rumex dentatus) on late sown wheat productivity (Variety HD 3059) while using cattle shed water for irrigation. The results revealed that late harvesting of the berseem led to the development of   R. dentatus up to seeding stage. Berseem green fodder contaminated with seeds of R. dentatus was fed to the cattle and buffaloes. Application of carfentrazone at 25 days after sowing (DAS) reduced the population of existing broad-leaved weeds, however, use of cattle shed water for irrigation increased the population of R. dentatus from 35 DAS up to 17% at 50 DAS, 134% at 65 DAS and 186% at 80 DAS. Whereas, the adjacent plot irrigated with normal ground water, recorded the declining trend of R. dentatus population from 35 DAS i.e. up to 15, 32 and 50% reduction at 50, 65 and 80 DAS, respectively. Large infestation of R. dentatus due to use of cattle shed water contaminated with seeds of R. dentatus reduced wheat productivity up to 44% (2.14 t/ha) as compared to the grain yield 3.82 t/ha obtained from the plot irrigated with normal ground water. During second year, the entire field was irrigated with normal ground water and similarly carfentrazone was used at 25 DAS. These measures reduced the population of R. dentatus and weed showed declining trend up to 30, 71 and 79% reduction at 50, 65 and 80 DAS from 35 DAS. These results confirmed that R. dentatus has the endozoochorous mechanism of its dissemination and use of cattle shed water for irrigation may not be recommended if the berseem fodder is infested with seeds of R. dentatus.