NUTRITION-PARASITE INTERACTION- A REVIEW

There are number of internal and external factors that affect the production performance of
animals, among which parasites and parasitism are major of concern constraints to animal’s productivity
especially in tropical countries. The usual mode of control of these gastro-intestinal parasites (GIP)
by based on the repeated use of anthelmintics is now strongly questioned because of the increasing
development of resistance to these molecules. Among the alternative methods to anthelmintics currently
available, the manipulation of host nutrition in order to improve the host resistance and/or resilience
to parasitic infections seems to represent one of the most promising options to reduce the dependence
on conventional chemotherapy and to favor the sustainable control of GIP. This paper will discuss
the interactions between nutrition and parasitism and will also refer to quantitative (influence of
protein, energy, micronutrients and other phyto-additives) as well as to qualitative (organic livestock
farming, foraging) aspects of the diet. The beneficial effect of nutrition, more specifically, the
importance of protein nutrition for the maintenance of host immunity to parasitism, the potential
use of novel crops and possibilities for biological control have also been discussed. Biological control
of parasitic nematodes seems to hold promise for the future, but to be able to assist producers; the
optimal delivery system needs to be refined and further developed. In addition, more work will be
needed to define anthelmintic resistance, non-chemical alternatives to parasite control, modulation
of immunity to parasites by genetic and nutritional factor, integrated parasite control strategy and
the best use of these technologies in different geographic regions. Internal parasites are a potentially
serious threat to the health, welfare and productivity of organically managed livestock, the ultimate
goal of which is to eliminate dependence on antiparasitic drugs, however this is rarely achieved in
practice. It is now realized that chemical anthelmintic treatment, on its own, may not provide a long
term strategy for managing parasite in grazing ruminants. There is a growing awareness for strategic
nutritional supplementation with far reaching consequences, viz. increased production of meat, milk
and wool, and also of its quality, growth and reproductive efficiency, parasite control, enhancement
of immunity and disease resistance.