The awareness of the demands for increased productivity has not been lacking. In fact, many attempts have been made to genetically improve livestock in the tropics. Although it should be recognized that improved livestock have been produced or successfully introduced in favourable areas of the tropics, e.g. in some highland areas, in maritime climates and in relatively intense peri-urban production systems, many attempts have failed [CS 1.3 by Mpofu]; [CS 1.6 by Mpofu & Rege]. There are at least three primary reasons for these failures:
- Lack of domestic resources and enough trained staff with animal breeding backgrounds. People from developed countries have usually been responsible for conducting improvement programmes. As a consequence of this lack of ‘indigenous’ knowledge, sophisticated methods, e.g. use of artificial insemination and progeny testing, have often been inappropriately applied, neglecting the necessary infrastructure [CS 1.3 by Mpofu].
- The introduction of cross-breeding with temperate high yielding breeds without a long-term plan on how to maintain either a suitable level of ‘upgrading’, or how to maintain the pure breeds for future use in cross-breeding. Upgrading to a level that is too high has generally led to animals without resistance to withstand environmental stress (Gibson and Pullin, 2005). However, there are examples of successful breed replacements in parts of India (Anjani-Kumar et al., 2003) and Africa (Ahuya et al., 2005), [CS1.40 by Chako] including the highlands of Kenya. Furthermore, use of cross-breeding and formation of synthetic breeds has been successfully demonstrated in Brazil and is one way of combining diverse genetic attributes of the different breeds (Madalena, 2005).
- The lack of analysis of the different roles of livestock in each specific area, usually leads to falsely defined breeding objectives and underrating the potentials of various indigenous breeds of livestock. Examples of these problems are illustrated in the case studies by Philipsson (2000) and in the comprehensive publications and reviews found in FAO (1993) and in Payne and Hodges (1997).
New approaches must better consider the potential of indigenous livestock breeds sometimes in cross-breeding with suitable exotic breeds, and realistic ways of improving them in the context of environmental and socio-economic demands and within the resources available. For this purpose, there is a great need to characterize the indigenous livestock breeds and their crosses to determine which are the most suitable ones for further improvement and to implement simplified, yet effective, breeding programmes [CS 1.7 by Khombe]; [CS 1.14 by Olivier]. Such programmes could be based on nucleus herds of pure and crossbred animals from which specified genotypes or semen can be widely disseminated to livestock herds (see Module 3, Section 4.3 & 4.4); [van der Werf in ICAR Tech. Series No. 3]; [Nitter in ICAR Tech. Series No. 3].