This issue of the ILCA Bulletin includes papers on the productivity of N'Dama cattle and their crosses with Sahiwals in Sierra Leone, the effects of diet restriction on the work performance of local Zebu and Friesian x Boran oxen in Ethiopia, ILCA's activities in agro-ecological zonation, and on animal breeding and performance studies in Africa.
The first paper examines the productivities of N'Dama cattle, introduced Sahiwal cattle and N'Dama x Sahiwal crossbreds in Sierra Leone. The authors found that the herd productivity of N'Dama cows with Sahiwal-sired calves was higher than that of N'Damas with N'Dama-sired calves, but that the productivity of purebred Sahiwals was not sufficiently greater than that of N'Dama cows with Sahiwal-sired calves to justify their use in Sierra Leone. The performance of the N'Dama x Sahiwal crossbreds needs further evaluation.
The second paper deals with the effects of diet restriction on the work performance and weight loss of local Zebu and Friesian x Boran oxen worked as singles. The crossbred oxen are heavier than the local cattle and generate more force, but also require more feed. In a trial carried out by ILCA it was found that the work performance of the crossbreds was significantly higher than that of the local animals, but that diet did not have a significant effect on this character. All the oxen in the trial lost weight during the 23-week cultivation season. The authors suggest that oxen in good condition at the beginning of the season are able to perform adequately as singles for at least 4 months even when they are poorly fed.
The third article examines ILCA's work in the field of agro-ecological zonation and its potential benefits. In a continent as large and as varied as Africa, much agricultural research is site specific - but with more precise definition of agro-ecological zones it is hoped that the applicability of research results to other areas of similar agro-ecological conditions can be more rapidly assessed. A greater understanding of the climate and its effects on agriculture will also enable increased use to be made of modelling to predict pasture, forage and crop responses to the environment, and hopefully will reduce the need for multilocation adaptation trials. Many other potentially exciting developments from this technology are outlined.
Little information is available in the literature that allows comparative studies to be made of animal breeding and performance in Africa, while much of the research done in Africa on these topics has never been published as journal articles or books with wide circulation. The fourth article in this issue of the ILCA Bulletin outlines the work being done by ILCA in collecting such "grey literature" and making it more widely available. It also summarises ILCA's studies of comparative breed performance using data from such "grey literature", and describes "IDEAS", a microcomputer-based animal performance recording system that will simplify the collection and analysis of animal breeding and performance data.
Paul Neate and
Inca Alipui, Editors
ILCA Bulletin, Publications Section, ILCA,
P.O.Box 5689, Addis Ababa, Ethiopia.
