28 research outputs found
Genetic trends for growth in the Gudali and Wakwa cattle breeds of Cameroon
(South African J of Animal Science, 2000, 30, Supplement 1: 36-37
Amélioration génétique bovine par voie de croisement et de sélection en Afrique Tropicale : Expériences du Cameroun
Ce travail passe en revue les résultats des travaux de recherches sur l’amélioration génétique des zébus locaux (Goudali, White et Red Fulani) par voie de sélection et de croisement avec les races exotiques (Holstein, Montbéliarde, Brahman américain, Jersiais, Tarentaise, Limousine et Charolaise). Ces travaux ont été conduits depuis 1952 dans les Centres de Recherches Zootechniques de Wakwa et Bambui par l’Institut de Recherches Zootechniques (IRZ, aujourd’hui connue sous le nom de l’Institut de Recherche Agricole pour le Développement) du Cameroun, en système d’élevage semi-intensif dans les zones des hautes savanes guinéennes et des hauts plateaux de l’Ouest Cameroun. Les données proviennent des rapports d’activité et de consultations, des publications scientifiques et des entrevues. L’objectif est de ressortir les résultats saillants utiles pour les décideurs politiques, les chercheurs et les éleveurs. Les principaux résultats montrent que le potentiel laitier des croisés est généralement supérieur (>4 litres) à celui des races locales (>3,5 litres). Les génotypes ayant moins de 75% de sang exotique sont les plus performants en lait et viande. Les causes de mortalité par ordre d’importance sont nutritionnelles (36,8%), accidentelles (29,6%), pathologiques (21,1%), parasitaires (7,7%) et reproductives (4,8%). Par rapport aux autres produits de croisement, les croisés Holsteins ont été plus lourds à la naissance (34,75 kg) avec une vitesse de croissance plus élevée (0,46 kg), une production laitière plus élevée (5,47 ± 0,17 litres), plus précoces (40,87 mois) et moins susceptibles au stress Nuenvironnemental. Pour la filière bovin-à -viande, les performances de viande de la race synthétique Wakwa sont légèrement supérieures à celles des zébus Goudali sélectionnés dans le cheptel local. Cependant, le taux de susceptibilité à la dermatophilose est estimé à 71,0%, 34,4% et 5,0% chez le pur, ½ et ¼ sang Brahman, respectivement. La sélection massale du zébu Goudali (variété Ngaoundéré) et la race synthétique Wakwa a permis d’obtenir des progrès génétiques significatifs, soient, respectivement, 8,60 kg et 20,40 kg. Cependant, les corrélations génétiques négatives entre les effets directs et maternels montrent que le progrès génétique serait davantage plus important si la sélection était concentrée sur les performances directes et maternelles. Les expériences d’insémination artificielle menées à la SODEPA et à « Tadu Dairy Cooperative Society»montrent que l’industrie laitière est une entreprise rentable avec un rapport bénéfice-coût de 4,21.
This work reviews the results of research on the genetic improvement of local zebus (Gudali, White and Red Fulani) through selection and crossbreeding with exotic cattle breeds (Holstein, Montbeliard, American Brahman, Jersey, Tarentaise, Limousine and Charolais). This work was started since 1952 by Institute of Animal Research (IRZ, now known as the Institute of Agricultural Research for Development) at the Wakwa and Bambui Research Centers, under semi-intensive management conditions in the high Guinea savannah areas of the Adamawa Plateau and the highlands of West Cameroon. Data were obtained from activity and consultation reports, scientific publications and interviews. The objective is to highlight salient findings that are useful for policy makers, researchers and livestock producers. The main results show that the milk potential of crosses is generally higher (>4 liters) than that of local breeds (>3.5 liters). Genotypes with less than 75% exotic blood had the best milk and meat production performance. The reported causes of mortality in order of importance are nutritional (36.8%), accidental (29.6%), pathological (21.1%), parasitic (7.7%) and reproductive (4.8%). Compared to the others crosses, Holstein crosses were found to be relatively heavier at birth (34.75 kg) with a higher growth rate (0.46 kg), higher daily milk production (5.47 ± 0.17 liters), earlier maturing (40.87 months), but more adapted to the breeding conditions and less susceptible to environmental stress. For the beef industry, the meat performance of the synthetic Wakwa breed is slightly better than that of the Gudali zebus selected from the local herd. However, the susceptibility rate to dermatophilosis was estimated at 71.0%, 34.4% and 5.0% in pure, ½ and ¼ blood Brahman, respectively. Individual selection of the Gudali zebu (Ngaoundéré subtype) and the synthetic Wakwa breed has resulted in significant genetic progress, 8.60 kg and 20.40 kg, respectively. However, the negative genetic correlations between direct and maternal effects showed that genetic progress would be more important if selection was concentrated on direct and maternal performance. Artificial insemination experiments conducted at SODEPA and Tadu Dairy Cooperative Society showed that the dairy industry is a profitable enterprise with a benefit-cost ratio of 4.21
White Fulani cattle of West and Central Africa
The paperreviews information on the White Fulani cattle under the headings; origin, classification, distribution, population statistics, ecological settings, utility, husbandry practices, physical characteristics, special genetic characteristics, adaptive attibutes and performance characteristics. It was concluded that the breed is economically important for several local communities in many West and Central Africa countries. The population of the breed is substantial. However, introgression from exotic cattle breeds as well as interbreeding with local breeds represent the major threat to the breed. The review identified a lack of programmes to develop the breed as being inimical to its long-term existence
Gudali cattle of West and Central Africa
The objective of this paper was to compile the available information in the conventional and non-conventional literature on the origin, distribution, ecological settings, utility, husbandry practices and production systems of the Gudali, a West and Central African shorthorned zebu which is similar in conformation, size and origin to the East African shorthorned zebu. These animals are reputed not only for their beef and dairy qualities but also for their hardiness to the harsh northerly environments. Under the prevailing circumstances in the pastoral systems, natural selection is the primary force affecting any circumstances in the pastoral systems, natural selection is the primary force affecting any genetic change and, as a result, animals tend to perform relatively poorly. Most of the documented studies have been limited in scope and applicability. Therefore, further studies are needed to adequately characterize these animals under their different production systems
White Fulani cattle of West and Central Africa
The paper reviews information on the White Fulani cattle. Discussions and data on breed origin, classification, distribution, population statistics, ecological settings, utility, husbandry practices, physical characteristics, special genetic characteristics, adaptive attributes and performance characteristics. The breed is economically important for several local communities in many West and central African countries with a substantial population. However, exotic cattle breeds as well as interbreeding with local breeds represent the major threat to the breed. This review identified lack of programmes to develop the breed as being inimical to its long-term existence
Performance characteristics of some eastern and southern African Zebu cattle breeds
The zebu cattle "breeds" of eastern and southern Africa are broadly classified into "large" and "small" types. Boran, Karamajong and Sudanese Zebu are examples of the former, while those of the latter include Angoni, Nkedi and Nandi. The habitat of the large zebu is drier than that of the small types. Growth, fertility, survival, carcass and milk produciton are the traits reviewed. Most of these traits show evidence of tremendous variability which may be due partly to differences in the production systems and agro-ecological zones and partly to the genotype. As expected, improved standards of management and reduced disease risk contribute to the remarkable performance characteristics of some breeds, notably the Boran and Angoni. The small zebus are more fertile than the large types, as expected.They are, thus, better apt for low-input production systems than the latter. Under improved nutrition, both breed types demonstrate high aptitudes to gain weight and to aproduce reasonable carcasses. On the other hand, the "large" types (e.g. Western Baggara and Boran) have evolved adaptive mechanisms to enable them overcome the long periods of feed scarcity as reflected in their great capacity to rapidly build-up body reserves during periods of pasture abundance. They also show characteristic ability for high rate of compensatory growth which enables them to achieve rapid and exceptional gains when fattened. The "unimproved" Orma Borann show greater ability to resist trypanosomiasis than "improved" Boran in Kenya. Although they produce both meat and milk, Butana and Kenana manifest greater dairy aptitudes, while Western Baggara and Boran show greater beef potentials. Selective breeding is, Thus, expected to enhance their meat and dairy potentials under moderate to high standards of feeding, management and disease control. Further studies are deemed necessary to fully characterise the biological performance and adaptation of these breeds in their natural environments