Deficiency on reproduction

O Gorman, J., F.H. Smith, D.B.R. Poole, M.P. Boland, and J.F. Roche. 1987. The effect of molybdenum-induced copper deficiency on reproduction in beef heifers. Theriogenology 27 265. 

Aside from these investigations, the effect of Mo deficiency on reproductive function has not yet been assessed (Anke et al. 

Tab. 9.4-22 Effect of iodine deficiency on reproductive performance of goats and mortality of kids...

The current leading hypothesis is that nuclear RAR and RXR play a direct role in this process. The retinoid receptors can be activated by physicochemical binding of free retinoic acid to RAR and RXR. Alternatively, covalent forms, such as retinoyl derivatives of RAR and RXR, might also exist. Interestingly, retinyl and retinoyl p-glucuronide stimulate the differentiations of HL-60 cells well without evident conversion to retinol and retinoic acid, respectively. Retinoic acid has also been implicated as a morphogen in embryonic development (18). The adverse effects of vitamin A deficiency on reproduction, growth, and the immune response, in all likelihood, are an expression of perturbations in the process of cellular differentiation. 

Quite often, retinoic acid, the acid form of vitamin A, is used to study the effects of vitamin A deficiency on reproduction, because it can be substituted freely for retinol and reti-naldehyde (the aldehyde form of vitamin A) for all physiological functions except reproduction and vision. 

Swenerton, H-, and Hurley, L, S, (1980), Zinc deficiency in rhesus and bonnet monkeys, including effects on reproduction. /. Wutr. 110,575-. 3. 

Anke M, Groppel B, Kronemann H and Fuhrer E (1983a) Influence of vanadium deficiency on growth, reproduction and life expectancy of goats. 

Anke M, Krause U and Groppel B (1987a) The effect of arsenic deficiency on growth, reproduction, life expectancy and disease symptoms in animals. In Hemphill DD, ed. Trace Substances in Environment Health — 21. University of Missouri, USA, pp. 533-550. 

Anke M, Keonemann H, Geoppel B, Henning A, Meissnee D and Schneider HJ (1980) The influence of nickel deficiency on growth reproduction longevity and different biochemical parameters of goats. In Anke M, Schneider HJ, Bruckner C, eds. 3. Spurenelement Symposium, Nickel, pp. 3-10. Wiss Beitr Karl-Marx-Univ. Leipzig u Friedrich-Schiller-Univ Jena. 

Anke M, Geoppel B, Keonemann H and Euheee E (1983) Influence of vanadium deficiency on growth, reproduction and life expectancy of goats. In Anke M et al., eds. 4. Spurenelement-Sym-posium, pp. 135-141. University Leipzig and Jena, Germany. 

At the most severe end of the spectrum this manifests as endemic cretinism, but even mild iodine deficiency can affect cognitive development and subsequent intellectual abifi-ties, as well as, causing deficits in hearing and reproduction (Bleichrodt and Born, 1994 Dunn, 1996 Hetzel, 2004). Detailed consideration of the effects of iodine deficiency on brain function can be found in the chapter in the handbook entitled Iodine Deficiency and the Brain by Basil Hetzel. 

Bedwal RS, Nair N, Mathur RS. 1991. Effects of zinc-deficiency and toxicity on reproductive-organs, pregnancy and lactation - a review. Trace Elements in Medicine 8(2) 89-100. 

Within cells, vitamin A (retinol, retinal, retinoic acid) functions mainly in vision, cellular differentiation, and embryogenesis. The adverse effects of vitamin A deficiency on complex physiological processes such as reproduction and the immvme response result primarily from defective cellular differentiation. 

Many nutrient deficiencies influence fertility indirectly, through their effects on the general metabolism of the animal. For example, phosphorus deficiency in grazing ruminants, which has often been associated with poor fertihty, appears to affect reproduction because it restricts many metabolic processes, hence food intake and the general plane of nutrition. However, there is also some evidence that phosphorus deficiency has a direct effect on reproduction through suppressing oestrous cycles. 

Deficiencies of protein, vitamins and minerais affect reproduction indirectiy, through their effects on the generai heaith of animais, but a few have more specific effects on reproduction. Thus, zinc deficiency in maies reduces the production of spermatozoa, and vitamin A deficiency causes congenitai abnormaiities in foetuses. 

Dunn T G and Moss G E 1992 Effects of nutrient deficiencies and excesses on reproductive efficiency of livestock. Journal of Animal Science 70 1580. 

Substances shall be classified in Category 2 for reproductive toxicity when there is some evidence from humans or experimental animals, possibly supplemented with other information, of an adverse effect on sexual function and fertility, or on development, in the absence of other toxic effects, or if occurring together with other toxic effects the adverse effect on reproduction is considered not to be a secondary non-specific consequence of the other toxic effects, and where the evidence is not sufficiently convincing to place the substance in Category 1. For instance, deficiencies in the study may make the quality of evidence less convincing, and in view of this. Category 2 would be the more appropriate classification. 

---