Pratik N. Sheth

Cow urine is widely utilized for medicinal and agricultural purposes in rural areas of India, with urine from indigenous cow breeds (Bos indicus) believed to offer unique benefits compared to that of exotic (Bos taurus) breeds. This research aimed to profile the metabolites present in the urine of indigenous breeds of cows using gas chromatography-mass spectrometry (GC-MS) and to explore the potential applications of the identified compounds by referencing the established literature. The various cow breeds included in the study were Gir, Sahiwal, Gangatiri, Hariana, Kankrej, Rathi, Gaolao, and Jersey. Cows employed in the study to collect the samples from various locations differed in their body weight, age, and stage of lactation. GC-MS analysis revealed a range of compounds, including ethanone, cresol, bis(2-ethylhexyl) phthalate, phenol, eicosane, pentanol, isobutyl ester, ethyl ester, binapacryl, trifluoroacetate, xylene, amylene hydrate, dibutyl ester, and formamide. Notably, several compounds were consistently observed across multiple indigenous breeds. For instance, bis(2-ethylhexyl) phthalate and xylene were found in nearly all indigenous breeds, while ethanone was detected in Gir, Sahiwal, Gangatiri, Kankrej, Hariana, Gaolao as well as Jersey cows. Similarly, eicosane and pentanol were present in Gangatiri and Hariana breeds. These overlapping chemical signatures highlight potential metabolic similarities among the studied cow breeds. The identified compounds are known for their diverse industrial and pharmaceutical applications, including use in disinfectants, flavorings, cosmetics, and agrochemicals as well as metabolic engineering. Thus, this study-for the first time-comprehensively delineated the comparative metabolite profile of cow urine among different breeds of cows. The spectrum of urinary metabolites identified could offer opportunities to foster bio-based innovations having multifarious applications, including new product developments, across diversified fields.

The forecasted global population growth is poised to create a greater exigency for livestock-derived food production, leading to a significant waste generation from the industrial-scale livestock operations, which necessitates to develop sustainable waste management solutions. The heightened demand for livestock and dairy products has driven a surge in cow waste (CW) production. While CW is typically used as organic fertilizer or solid fuel, improper disposal poses potential environmental hazards. Anaerobic digestion and composting transform CW into valuable products, such as biofuels and organic fertilizers, with the potential for electricity and heat generation, biochar production, and advanced friction materials. The CW contains essential inorganic and organic compounds vital for plant functions, including lignin, cellulose, hemicellulose, nitrogen, and minerals such as potassium, sulfur, iron, magnesium, copper, cobalt, and manganese. Additionally, the rich microbial diversity in cow dung drives the production of bioenergy carriers like biomethane and biohydrogen, promoting cost-effective energy generation and environmental sustainability. This review employs bibliometric analysis to explore the latest trends in CW applications, with a particular focus on innovative applications such as cellulose extraction, biochar production, microbial fuel cells, and nanoparticle synthesis. It further evaluates the environmental impacts of these technologies and assesses their potential to advance sustainable and cleaner frontiers in the valorization of CW. Graphical Abstract