Keynote Address - The future of the African bee: A call to mainstream beekeeping to enhance delivery of the Malabo declaration

No Abstract

Comparative digestive ability and rumen microbial community of N’Dama and N’Dama x Jersey cattle fed different diets

Rumen fluid collected from three rumen fistulated N’Dama and three crossbred animals fed three different diets at medium supplementation level, was used to compare the plant cell wall degrading community of the two breeds of cattle. In vivo digestibility was also examined and compared using 12 animals (six of each breed) fed the same diets. The microbial community of the rumen was analyzed by 16S rRNA hybridisation, using phylogenetic probes of different levels: a universal probe, domain-specific probes for Bacteria, Eukarya and Archaea, and probes targeting cellulolytic organisms: Chytridiomycetes, Fibrobacter spp., Ruminococcus albus and Ruminococcus flavefaciens. In vivo, organic matter (OM) and neutral detergent fibre (NDF) digestibility were significantly higher in N’Dama compared to crossbred animals when they were fed either baby corn stover and concentrate, or groundnut hay and moringa. In contrast, when the animals were fed groundnut hay and concentrate there was no difference in OM and NDF digestibility between the two breeds. Results of the microbial community analysis showed that RNA concentration of total Bacteria and Archaea was not affected by the breeds of animal, but were significantly affected by diet. The eukaryotic RNA concentration was higher in crossbred animals compared to the N’Dama and was not affected by the diet. Fibrobacter and R. flavefaciens RNA concentrations (μg/mL) were significantly dependent on diet and breed. Ruminococcus albus and Chytridiomycetes RNA concentrations were neither affected by the breed, nor by the diet of the animals. This suggested that the differences between breeds observed in digestibility could be partially explained by the composition of the cell wall degrading community._______________________________________________________________________________

Effects of Donor diets, breed and increasing level of supplementation on in vitro gas production parameters

In vitro fermentation studies were undertaken to evaluate the effects of donor diets and breeds on fermentation parameters. Rumen fluid from 3 N’Dama and 3 crossbred donor animals was used for 24 hour in vitro fermentations. The donor animals were fed consecutively the same three diets Baby corn Stover plus concentrate (BCS:Co), Groundnut hay plus concentrate(GNH:Co) and Groundnut hay plus moringa(GNH:Mo) at 20% level of supplementation. Each of these inocula was incubated with substrates consisting of BCS:Co, GNH:Co and GNH:Mo at 5 levels of supplementation, plus supplement alone. The breed of the donor animals did not significantly affect 24 hour gas production, but short chain fatty acid concentration was higher with rumen fluid from crossbreds when donors were fed BCS:Co and GNH:Mo. Moringa meal as supplement to donor animals changed the fermentation pattern of all the substrates, such that gas production and SCFA increased substantially in groundnuthay based substrates, whereas gas production of BCS:Co substrates decreased and SCFA did not substantially change. In vitro digestibility was higher with rumen fluid from N’Dama whatever the diet of donor animals and the substrate incubated. Thus, when testing a supplementation strategy in vitro, it should be important that donor animals are fed the same components (roughage and supplement) that will be combined at different levels in vitro, whilst the breed of donor animals may be of second importance. This work provides conclusive evidence that in vitro incubations may be used to design supplementation strategies, thus reducing the need for in vivo experiments

Investing in livestock to drive economic growth in Africa: Rationales and priorities

No Abstrac

Effects of gastrointestinal helminth infections and plane of nutrition on the health and productivity of F1 (West African Dwarf x Sahelian) goat crosses in The Gambia

A two by two factorial design including natural helminth infections (dewormed 'D' or not dewormed 'ND') and different levels of diet (basal 'B' or basal diet plus supplement 'S') was used to assess the effect of helminth infections and plane of nutrition on health and productivity of F1 (West African Dwarf (WAD) x Sahelian) crosses. The pasture composed the basal diet and supplemented animals received cottonseed and rice bran. Feed composition analysis revealed that the pasture did not provide sufficient nutrients for reproduction requirements. Feed supplementation had a significant effect on weight gain of does during pregnancy and lactation, and milk off-take was significantly higher in supplemented does compared to non-supplemented ones (31.3 +/- 2.5 1 versus 17.7 +/- 2.5 1 respectively, P < 0.01). A peri-parturient rise in strongyle egg output was noted, and diet supplementation tended to reduce faecal egg count and to increase packed cell volume (PCV), mainly during the dry season. Deworming had a significant effect on red blood cell (RBC) count, PCV and haemoglobin (Hb) concentration, mainly during the period of peak strongyle egg output (season x deworming: P < 0.001 for RBC and PCV and P < 0.05 for Hb). Helminth infections combined with a basal diet seriously affected weight gain but the interaction of deworming and diet was not significant. In groups receiving the basal diet, dewormed animals had a significantly higher milk yield than those that were not dewormed (23.5 +/- 3.31 versus 12.0 +/- 3.71, respectively; interaction diet x deworming: P < 0.05). The higher daily weight gains of offspring born from dewormed does might be explained by the fact that, in addition to the effect of deworming on milk yield in animals receiving basal diet, the kids were less exposed to helminth eggs, whereas does that were not dewormed constituted a greater source of helminth infection for their kids. (C) 2003 Elsevier Science B.V. All rights reserved