Abstract
Livestock plays an important role in the national economy and has a significant share in the gross domestic product of Pakistan. Parasitic diseases and worm infestations negatively affect their health, production, and reproductive performance. In addition, parasitic infestation in livestock reduces gross production values and renders huge economic losses globally. Among the parasites, the most important are nematodes. They are distributed worldwide and affect all kinds of livestock. This review aimed to elaborate on the main gastrointestinal nematodes, their mode of action, impacts on livestock and their control (physical, chemical or biological) strategies. Common examples of nematode worms infesting the livestock are Ascaris, Hemonchus, Strongyloids, Trichostrongyliods, Ostertagia, Trichuris, Dictyocaulus, Trichnellia, Enterobius, Cooperia, Gunagylonema, Chabertia, and Oesphagostomum. The gastrointestinal nematodes are detrimental to the animals’ health. Nematodes primarily affect animals’ feed consumption and efficiency, and severe ailments result in the death of the affected animals. The production and health losses primarily depend on the age of the animals, the degree of severity of worm infestation, epidemiology pattern of the parasites, management strategies of the flocks, and ecoclimatic conditions which are favorable for the worm’s infestation. To minimize these issues, farmers should be educated on the importance of intensive livestock management and environmental sanitation, as well as strategic deworming of cattle using efficient broad-spectrum anthelmintics, biological control of the parasites, and breaking their life cycle and intermediate hosts.