A survey of tick spatial and seasonal distribution in traditional managed N'Dama cattle over 1 year old was carried out in The Gambia over 16 months. Presence of Anaplasma marginale and Babesia spp. in the blood smears and their antibodies in the serum of same animals were also examined. Tick species, in decreasing order of abundance, were: Boophilus geigy, Rhipicephalus senegalensis, B.decoloratus, Hyalaomma truncatum, H.marginatum rufipes and Amblyomma variegatum. All tick species peaked during the rainy season. Additional B.geigy peaks occurred towards the end of the dry season. The most infested animal body areas were anogenital, udder and abdomen. A.variegatum, Hyalomma spp. and, to a lesser extent, Boophilus spp. showed strong preferences for these anatomical regions. Overall prevalence of A.marginale, B.bigemina and B.bovis haemoparasites were 3.2%, 0.9% and 0.1%, respectively. Peaks of A.marginale and B.bigemina occurred at the end of the rainy season-beginning of the dry season; an additional A.marginale peak was observed at mid-end dry season. Overall antibody seroprevalence were 29.6% for A.marginale, 44.7% for B.bigemina and 5.2% for B.bovis; monthly fluctuations in percentage of seroreactors were limited. Endemic stability for A.marginale and B.bigemina is postulated. Implications of the outcomes are discussed in relation to tick-control strategy in The Gambia.

SummaryThis paper reviews the successful N'Dama cattle genetic improvement programme implemented in a low input production system at the International Trypanotolerance Centre (ITC) in 1994, in The Gambia. The first part of the paper presents the genetic improvement programme. The second part deals with the analysis of the genetic improvement programme. The success of the genetic improvement programme expressed through genetic progress and the benefits for the farmers is encouraging. Recommendations to strengthen the implementation process in the field are made. RésuméCet article se donne pour objectif de passer en revue le programme d'amélioration génétique du bétail trypanotolérant N'Dama. La première partie de l'article fait découvrir le programme d'amélioration. La seconde partie traite particulièrement de l'analyse du programme, cette analyse se base sur le progrès génétique obtenu et les bénéfices que peuvent en tirer les éleveurs. Pour conclure, certaines recommandations pour le renforcement du programme d'amélioration génétique sont proposées.

A questionnaire and a census were carried out in 1998/99 on 201 cattle herds in 44 villages located in three different areas of The Gambia, in order to obtain information about the ownership pattern, management and breeding practices for optimizing and extending a pure breeding scheme for indigenous N'Dama cattle. The herds had an average of 58.5 head, of which 39.3% were cows, and most of them were multiowner herds, having on average 5.5 owners. Overall, women represented 38.3% of the owners, but they owned only 15.9% of the cattle. Some of the senior herdsmen received no payment, as they were family members, but most of them received payment in kind, i.e. milk off-take from the herd. Payment in cash only or cash as well as milk was rare. In larger herds it was quite common for additional herdsmen to be hired throughout the year, their payment shifting towards cash only or cash and milk. Many small herds had no older bulls or breeding bull and almost all breeding bulls were born within the herd. In most cases, it was the herd owner who was responsible for the selection of the breeding bull. Traits related to the growth and milk production of the dam were considered as most important for a good breeding bull. The results are discussed with respect to the extension of a pure breeding scheme for N'Dama cattle.

Goats are important in the low-input systems of West Africa and their main importance lies in their role for income and saving. In addition, it is known that milk offtake for home consumption is also important. In order to obtain information about the real importance of milk offtake, a recording scheme was operated in 27 villages in the Central River Division of The Gambia from July 1998 until January 2000. Detailed information was obtained from about 1500 kiddings. In the recording scheme, any sheep being milked as well as the goats of the International Trypanotolerance Centre nucleus flock were also recorded. In the villages, 36% of all lactations were used for milk offtake, but the fraction milked was lower for the first two lactations. The average length of lactation was 127 days and the average daily milk offtake was 0.18 L. Goats are milked once a day and the residual milk is left for the kids. Milking starts about one week after parturition and stops when the goat becomes pregnant or the kid(s) die or the goat is drying off. The repeatability of the 90-day milk offtake was 0.24 +/- 0.09. Sixty-five percent of goat owner were women and a large fraction of goat owners also owned cattle. Goat milk was used exclusively for home consumption. It is concluded that in breeding and extension work more attention should be given to aspects of milk production.

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