A REVIEW ON THE EFFECT OF ENDOCRINE DISRUPTORS ON REPRODUCTIVE PERFORMANCE OF SMALL RUMINANT

Abstract

Endocrine disruptors (ED's) exist in a wide range of forms, both naturally and artificially. Exposure of animals to ED's may happen in several ways, including feeding urea or human sewage sludge treated crop residues, straws, and stovers of crops treated with pesticides, cereals infected with mycotoxins, and fodder crops containing naturally offending endocrine-disrupting compounds, among others. The ED's can affect the animals’ endocrine system, fertility, and overall reproductive performance (RP) of both the parent and their offspring regardless of their sex. The adrenal gland and reproductive system are the most vulnerable to ED's. Moreover, they can cause health risks by compromising the animal immune system. Residues of these compounds may find their way to the human body by consuming affected animal products. On this note, the present review aimed to explore some of the available naturally occurring ED's in fodder crops, their effects on small ruminant (SR) endocrine functions, RP, and the measures that could be adopted to reduce the adverse effects of ED's on SR. Maintaining animals just before and at joining on forages containing offending ED's has negative consequences on the animals’ RP. The effect may be reflected in the RP of the affected animals’ offspring later in their life. Moreover, most of the studies on ED's containing forages were conducted on temperate forage crops. There is, therefore, a need for similar studies on tropical forage crops. Timely assessment of the ED's levels in the most widely use forages known to contain the offending ED's is also needed, as their quantity may vary with time due to consistent climate change, agronomic practices, and other human activities.

Keywords

• small ruminants
• reproductive performance
• fodder crops
• endocrine disruptors
• and phytoestrogens