Towards household food and nutrition security in semi-arid areas: What role for condensed tannin-rich ruminant feedstuffs?

The global demand for food is projected to continue its upward trend for at least another 40 years while undernutrition among infants, young children, and women remains a major problem. These challenges of food and nutrition insecurity are particularly pronounced in the semi-arid regions of the world. In semi-arid areas, ruminant animal production often represents the best option to meet the projected demand for food since crop production is constrained by erratic rainfall patterns. However, the productivity of ruminant animals in these semi-arid regions is generally accepted to be too low to meet the demand for animal products. This yield gap occurs due to various production constraints that will be explored in this review. Chief among these constraints is the fluctuation in quantity and quality of feed due to growing conditions that only support seasonal growth of grasses in rangelands. Complementing grasses as a source of feed for ruminant animals, is a collection of shrub and browse tree products that can be used during the long dry seasons. Although ubiquitous and, as such, a potential solution to feed shortages, browse products tend to contain secondary plant compounds especially tannins, whose effect on the nutrition of the ruminant is far from being unequivocal. Recent evidence also shows tannins improve composition, quality and shelf life of ruminant products. This review is designed to explore ways through which the beneficial nutritional effects of tannin-rich browse products can be maximized to plug the animal product yield and quality gap and improve food and nutrition security in semi-arid areas of low-income food-deficit countries. (C) 2015 Elsevier Ltd. All rights reserved.