HL Deb 16 July 1998 vol 592 c40WA
The Countess of Mar

asked Her Majesty's Government:

What are the known immune system and reproductive system effects of deficiency in (a) copper and (b) selenium in cattle. [HL2589]

Lord Donoughue

Copper and selenium are essential constituents of the diet. Severe deficiency of either can result in death. Sublethal deficiencies can affect the normal function of a wide range of body systems.

Copper deficiency in cattle has been implicated in both impaired function of the immune defence system and poor fertility though, despite extensive investigation, neither has been conclusively proven.

There is some evidence that selenium deficiency in cattle affects animals' ability to mount antibody response to infection and animals' defence cells are less able to kill or remove pathogenic bacteria. The evidence regarding the effect of selenium deficiency on the reproductive system is conflicting. It has been associated with retained foetal membranes and inferior reproductive performance, but the scientific evidence is equivocal.