The use of wastewater for rearing domestic animals is a common phenomenon in most of the developing countries like Pakistan that face a serious shortage of freshwater resources. However, most of the literature has only focused on the indirect effects of wastewater use on animal health or productivity, and literature on the direct effects of wastewater use is rare. Therefore, this study aims to investigate the direct and indirect effects of wastewater usage on the prevalence of animal diseases and animal health in Pakistan. The study is based on a household-level survey of 360 domestic water buffalo herds collected from 12 districts of Punjab Province, Pakistan. We tested the prevalence of the animal's diseases, animal's health, and wastewater-use preference with various econometric tools, such as the Poisson, negative binomial, and logistic regressions. The findings of the study show that the majority of the farmers use wastewater for buffalo bathing due to the shortage of freshwater resources. Results explore the prevalence of diseases such as clinical mastitis, tick infestation, and foot and mouth disease at the farm level significantly associated with buffalo bathing in the wastewater. Moreover, bathing in wastewater pre- and post-milking also plays a role in the occurrence of diseases. Particularly, if the buffalo's access to wastewater for bathing is within 60 min after milking, the probability of the animals being exposed to mastitis is higher. Furthermore, on investigation, a number of factors are found, such as the distance to the water source, power shortage, groundwater availability, and the education of farmers that influence farmers' behavior of letting their animals take a bath in wastewater. Moreover, the use of different preventive measures improves the animal's health.
Keywords: Animal’s health; Clinical mastitis; Foot and mouth disease; Logistic regression; Non negative binomial regression; Poisson regression; Tick infection; Wastewater.