Abstract
► We evaluated mineral nutritive potential of fodder species irrigated by sewage water. ► Mg, Zn and Co concentrations in six fodder species affected by irrigation water quality were examined. ► The information may be used under similar agro-ecological conditions. ► Mineral supplementation may be given to control diseases for optimum animal production. ► Welfare effects depend on ex-ante or ex-post assumptions about quality information.
Investigation was performed to assess the effect of different sewage water treatments on the metal status of different fodder species consumed by ruminants under semi-arid conditions. Five samples each of six fodder species viz.,
Trifolium alexandrinum
,
Cichorium intybus
,
Avena sativa
,
Medicago polymorpha
,
Brassica campestris
and
Medicago sativa
were collected from three fields irrigated with canal water, mix water (canal water and sewage water) and sewage water, respectively. Fodder samples were analyzed to determine the Mg, Co and Zn concentrations in shoots. Higher values of these metals were found in fodder species irrigated with sewage water relatively. Mg and Zn concentrations in all the fodder species were found to be below the critical level among all treatments. Whereas, concentrations of Co in the different fodder species were significantly different (
p < 0.05
) and above the critical level. Consequently, ruminants feeding on these fodder species need continued mineral supplementation of Zn and Mg elements to prevent diseases caused by the deficiency of these elements, and to support optimum animal productivity.