Incorporation du coprah et des cuticules de cacao et d’arachide dans l’aliment du (tilapia du nil( (Oreohromis niloticus, linné, 1758) eleve en etang : Effet sur la croissance et la composition biochimique

Dans le but de réduire le coût de l’alimentation du tilapia en élevage, quatre aliments exogènes pulvérulents dont un industriel (Ivograin) servant de référence (AR) et trois tests locaux (A1, A2 et A3) formulés uniquement à base de sous-produits locaux ont été utilisés. La composition de base des aliments tests est : A1 (cuticules de de fève de cacao, son de maïs, tourteaux de soja et coton) ; A2 (cuticules de graine d’arachide, son de maïs, tourteaux de soja et coton) et A3 (tourteaux de coprah, soja et coton et son de maïs). Tous les aliments titrent environ 28 % de protéines. L’expérience est conduite à la ferme « Blondey » (Côte d’Ivoire) sur des juvéniles de Oreochromis niloticus d’un poids initial de 33,3 ± 0,4 g. Des juvéniles ne recevant pas d’aliment exogène ont servi de lot témoin (At) pour apprécier l’effet de l’aliment endogène. La densité de stockage était de 2 poissons/m2. Trois étangs par traitement ont été utilisés. La ration journalière a été distribuée à 9 h et à 15 h. Après 180 jours d’expérience, les poids moyens finaux ont atteint des valeurs respectives de 273,42 ± 26g ; 295,08 ± 18,5 g ; 352,1 ± 20,7g ; 309,38 ± 22,3 g et 101,06 ± 4 g pour A3, A2, A1, AR et At. Au niveau des aliments exogènes, le meilleur quotient nutritif (Qn= 2,22) et de croissance journalière (1,77 g/jour) ont été obtenus avec A1. Le plus grand Qn (2,88) et la plus faible croissance journalière (1,33g /jour) sont enregistrés avec A3. La comparaison de tous les lots indique que la plus faible croissance (0,38 g/jour) est enregistrée chez les poissons non nourris à l’aliment exogène (At). Les lipides corporels (16 - 17 %) sont plus élevés chez les poissons nourris aux aliments tests que ceux des lots de référence (14 %) et témoins (13 %). Par rapport à l’aliment AR, les aliments tests réduisent le coût de revient de l’aliment et le coût de l’alimentation par unité de prise de poids de 15 - 18 % et 3,1 - 27,4 %, respectivement.Mots clés : Aliments, arachide, cacao, coprah, cuticules, Oreochromis niloticusEnglish AbstractIncorporation of coconut oil cake, cocoa bean shell and peanut skin in diet for nile tilapia (Oreohromis niloticus, linné, 1758) reared in pond : Effect on growth and biochemical compositionIn order to reduce feeding cost of rearing tilapia, four powdered diets including an industrial product (Ivograin) (as reference = AR) and three practical diets (A1, A2 and A3) formulated using local by-products were used. Formulated diets were designated as A1 (cocoa bean shell, corn bran, soybean oil cake, cottonseeds oil cake, premix), A2 (peanut skin, corn bran, soybean oil cake, cottonseeds oil cake, premix) and A3 (corn bran, soybean oil cake, cottonseeds oil cake and coconut oil cake). The four diets contained approximately 28 % crude protein. The experiment was carried out at farm « Blondey » (Ivory Coast) on fingerlings Oreochromis niloticus with an initial body weight of 33.3 ± 0.4g. In addition, fingerlings non-fed with exogenous diet were used as control group to assess the impact of the natural food. The used stocking density was 2 fish/m2. Three replicate ponds were assigned to each of the treatment. Fish were fed twice daily (9.00 h and 15.00 h). After 180 days of experiment, the final body weight observed were respectively 273.42 ± 26 ; 295.08 ± 18.5 ; 352.1 ± 20,7 ; 309.38 ± 22.3 g and 101.06 ± 4 g for A3, A2, A1, AR and At. Considering the four diets (A1, A2, A3 and AR), the best daily weight gain (1.77 g/day) and feed conversion ratio (2.22) were obtained with A1 which were significantly different (p < 0.05) from values obtained for the other groups. The poorest weight gain (1.33 g/day) and the highest feed conversion ratio (2.88) were recorded for A3. The comparison of all groups (A1, A2, A3, AR and At) revealed that the poorest value of the daily weight gain (1.33 g/day) was recorded for the control group (At). Fat deposition was highest (16 - 17 %) in fish fed practical diets, while fish fed diets AR and control fish (At) recorded respectively (14 %) and (13 %). Practical diets reduced the feed cost and feeding cost per unit of weight gain by 15 - 18 % and 3.1 - 27.4 %, respectively.Keywords : Diets, peanut skin, cocoa bean shell, coconut oil cake, Oreochromis niloticu

Rupture Uterine Par Accident De La Voie Publique: A propos d’un cas.

Un cas de rupture utérine par accident de la voie publique associée à une fracture de l’humérus droit et du bassin est décrit. Les pronostics maternels et foetal sont discutés à la lumière de la revue de la littérature

Water quality and water-use conflicts in Lake Taabo (Ivory Coast)

The Lake Taabo (Ivory Coast, Africa) results of the construction of the Taabo dam on the Ban- dama River. The changes in the water level of the 69-km² lake depend on 1) the rainfall linked to alternating dry/wet seasons; 2) the extraction of water for human uses; 3) the discharge of water from the upstream dam and the volumes tur- bined by the Kossou dam; 4) the various an- thropic effects (discharge of untreated waste water from towns and industries, and leaching from agricultural land). The average concentra- tions of nutrients (NH4-N: 1.1 mg/L, NO3-N: 1.62 mg/L, PO4-P: 10 mg/L, SiO2: 15 mg/L) and chlo- rophyll a (from 4.8 to 16.5 μg/L, average 11.4 μg/L) indicates some degree of eutrophication. The cumulated effects that threaten the ecosys- tem (degradation of water quality and eutrophi- cation) are such that they are likely to interfere with various water uses. In a context of growing health and environmental concerns in Africa, this study demonstrates conflicts between dif- ferent uses of this water resource and the urgent need for an appropriate policy including specific monitoring of lake water quality, wastewater control, and a programme to reduce agricultural fertilizers

Production de Oreochromis niloticus avec des aliments à base de sousproduits agricoles

Des alevins de Oreochromis niloticus (0,7 ± 0,06 g) ont été nourris dans seize étangs avec quatre aliments dont trois aliments tests (A1, A2 et A3) formulés uniquement à base de sous-produits agricoles. La composition de ces aliments tests est la suivante : A1 (tourteaux de soja, de coton, sons de maïs et de mil) ; A2 (tourteaux de soja, de coton, sons de maïs et de riz) et A3 (tourteaux de soja, de coton, sons de mil et de riz). Le quatrième (At), contenant de la farine de poisson, est un produit industriel et a servi de témoin. Deux densités de mise en charge (10 et 13 ind./m2 ) ont été appliquées pour chaque traitement alimentaire. Chaque densité d\'élevage a été répliquée une fois. Après 120 jours d\'élevage, tous les poissons ont atteint au moins 25 g (poids seuil de sexage). Les meilleures performances zootechniques sont obtenues avec l\'aliment A1, suivi de l\'aliment A2. Les poids moyens finaux observés aux densités 10 et 13 ind./m2 sont de 54,69 ± 7,76 et 46,77 ± 5,87 g (A1), 46,32 ± 6,71 et 41,23 ± 5,32 g (A2) ; 40,90 ± 7,64 et 37,31 ± 5,73 g (A3) puis de 41,72 ± 6,57 et 37,45 ± 5,84 g (At). Les quotients nutritifs respectifs correspondants sont de 1,13 ; 1,30 ; 1,87 et 1,72 (10 ind. /m2), puis de 1,40 ; 1,63 ; 1,74 et 1,80 (13 ind. /m2). Les aliments A1 et A2 permettent un niveau de production supérieur à celui du témoin. Comparés au témoin, des taux de réduction respectifs de 30 % et d\'environ 14 à 37% des coûts des aliments tests et de production des fingerling ont été obtenus..Alevins of Oreochromis niloticus (0.7 ± 0,06 g) were fed with three test diets (A1, A2 and A3) formulated using agricultural by-products and a commercial one containing fish meal (control diet = At). The composition of these test diets is: A1 (oilcakes of soy, of cotton, bran of corn and of millet); A2 (oilcakes of soy, of cotton, bran of corn and of rice) and A3 (oilcakes of soy, of cotton, bran of millet and of rice). Two stocking densities (10 and 13 ind. / m2) were applied for each experimental diet. At the end of 120 days of rearing, all experimental fish reached more than 25g (doorstep weight for manual sexing). Diets A1 and A2 displayed the better growth and food utilization performances. Final mean weight of fish at stocking densities 10 and 13 ind. / m2 respectively, ranged from 54.69 ± 7.76 to 46.77 ± 5.87 g (A1), 46.32 ± 6.71 to 41.23 ± 5.32 g (A2); 40.90 ± 7.64 to 37.31 ± 5.73 g (A3) and 41.72 ± 6.57 to 37.45 ± 5.84 g (At). The corresponding food conversion rates were 1.13; 1.30; 1.87 and 1.72 (10 ind. /m2), then 1.40; 1.63; 1.74 and 1.80 (13 ind. /m2). Test diets A1 and A2 produced more yield than the control one. Relatively to the assessment economic aspect, test diets reduce the diet cost and fingerlings production cost, respectively of rate about 30 % and 14 to 37 %, compared to that of the control diet. Keywords: Oreochromis niloticus, feeding, agricultural by-products, production, Côte d\'Ivoire.Sciences & Nature Vol. 5 (1) 2008: pp. 89-9

FISH DIVERSITY ALONG THE LONGITUDINAL GRADIENT IN A MAN–MADE LAKE OF WEST AFRICA, TAABO HYDROELECTRIC RESERVOIR, IVORY COAST

Fish assemblage patterns in Taabo Reservoir, a hydroelectric lake of Ivory Coast, were studied and related to the longitudinal gradient (river–dam gradient) composed of riverine, transitional, and lacustrine zones. Data were collected at 5 stations and each one was sampled during 5 surveys. Fish community structure was analysed using alpha and beta diversity indices. In total, 53 fish species were obtained in the whole ecosystem. Total species richness recorded at each ecological zone was 42, 43 and 45 species respectively in the riverine, transitional and lacustrine zones. Alpha diversity did not differed significantly along the longitudinal gradient but reached the highest value (33 species) in the transitional zone and the lowest (18 species) occurred in both the riverine and lacustrine zones. Temporal variability of Alpha diversity according to the hydrological regime of the lake differed with the zone. Beta diversity showed that fish assemblages similarity was higher between the transitional and the riverine zones (βw = 0.43) and lower between the riverine and the lacustrine zones (βw = 0.79)

The diurnal primate community of the Tanoé Forest: species composition, relative abundance, distribution, polyspecific associations and conservation status

The Tanoé Forest is located within the original distribution area of the Miss Waldron red colobus (Piliocolobus badius waldronae), the diana roloway (Cercopithecus diana roloway) and the white napped mangabey (Cercocebus atys lunulatus). These three monkey species are classified by IUCN among the 25 most threatened monkeys of the world. Surveys conducted in their believed distribution area in Côte d’Ivoire from 2004 to 2007 highlighted an advanced degradation of habitats, an intensive hunting activity and a subsequent local extinction of some primate species. Field survey conducted in the Tanoé Swamp Forest shown that there is an exception in this dramatic context since this forest still housing threatened species such as the Diana roloway, the white-napped mangabey, and other monkeys of conservation concern: the Geoffroy’s colobus (Colobus vellerosus) and the olive colobus (Procolobus verus), and probably a viable Miss Waldron monkeys population (Piliocolobus waldronae). In addition, this forest hosts the Lowe’s guenon (Cercopithecus campbelli lowei) and the lesser spot-nosed guenon (Cercopithecus petaurista petaurista), that are widespread in the Tanoé Swamp Forest.Keywords: Tanoé forest, primate community, endangered, Swamp Forest, distributio

RAZNOLIKOST RIBA U UMJETNOM JEZERU ZAPADNE AFRIKE, HIDROELEKTRANA TAABO, OBALA BJELOKOSTI

Fish assemblage patterns in Taabo Reservoir, a hydroelectric lake of Ivory Coast, were studied and related to the longitudinal gradient (river–dam gradient) composed of riverine, transitional, and lacustrine zones. Data were collected at 5 stations and each one was sampled during 5 surveys. Fish community structure was analysed using alpha and beta diversity indices. In total, 53 fish species were obtained in the whole ecosystem. Total species richness recorded at each ecological zone was 42, 43 and 45 species respectively in the riverine, transitional and lacustrine zones. Alpha diversity did not differed significantly along the longitudinal gradient but reached the highest value (33 species) in the transitional zone and the lowest (18 species) occurred in both the riverine and lacustrine zones. Temporal variability of Alpha diversity according to the hydrological regime of the lake differed with the zone. Beta diversity showed that fish assemblages similarity was higher between the transitional and the riverine zones (βw = 0.43) and lower between the riverine and the lacustrine zones (βw = 0.79).Uzorci riba jezera hidroelektrane Taabo u Obali Bjelokosti proučavani su u odnosu na uzdužni gradijent (rijeka — nasip) koji se odnosi na riječnu, prijelaznu i jezersku zonu. Podaci su sakupljani na pet lokaliteta. Struktura zajednica riba analizirana je s pomoću alfa i beta–indeksa raznolikosti. Ukupno u cijelom ekosustavu bile su 53 vrste riba. Ukupno bogatstvo vrsta zabilježeno na svakoj ekološkoj zoni jest 42, 43, odnosno 45 vrsta, i to u riječnoj, jezerskoj i prijelaznoj zoni. Alfa–raznolikost nije se značajno razlikovala duž uzdužnoga gradijenta već je dosegla najvišu vrijednost (33 vrsta) u prijelaznoj zoni, a najnižu (18 vrsta) u riječnoj i jezerskoj zoni. Beta–raznolikost je pokazala da je veća sličnost riba kod prijelazne i riječne zone (βw = 0,43), a niža između riječne i jezerske zone (βw = 0,79)

A Theoretical Exploration of Birhythmicity in the p53-Mdm2 Network

Experimental observations performed in the p53-Mdm2 network, one of the key protein modules involved in the control of proliferation of abnormal cells in mammals, revealed the existence of two frequencies of oscillations of p53 and Mdm2 in irradiated cells depending on the irradiation dose. These observations raised the question of the existence of birhythmicity, i.e. the coexistence of two oscillatory regimes for the same external conditions, in the p53-Mdm2 network which would be at the origin of these two distinct frequencies. A theoretical answer has been recently suggested by Ouattara, Abou-Jaoudé and Kaufman who proposed a 3-dimensional differential model showing birhythmicity to reproduce the two frequencies experimentally observed. The aim of this work is to analyze the mechanisms at the origin of the birhythmic behavior through a theoretical analysis of this differential model. To do so, we reduced this model, in a first step, into a 3-dimensional piecewise linear differential model where the Hill functions have been approximated by step functions, and, in a second step, into a 2-dimensional piecewise linear differential model by setting one autonomous variable as a constant in each domain of the phase space. We find that two features related to the phase space structure of the system are at the origin of the birhythmic behavior: the existence of two embedded cycles in the transition graph of the reduced models; the presence of a bypass in the orbit of the large amplitude oscillatory regime of low frequency. Based on this analysis, an experimental strategy is proposed to test the existence of birhythmicity in the p53-Mdm2 network. From a methodological point of view, this approach greatly facilitates the computational analysis of complex oscillatory behavior and could represent a valuable tool to explore mathematical models of biological rhythms showing sufficiently steep nonlinearities

Noise Amplification in Human Tumor Suppression following Gamma Irradiation

The influence of noise on oscillatory motion is a subject of permanent interest, both for fundamental and practical reasons. Cells respond properly to external stimuli by using noisy systems. We have clarified the effect of intrinsic noise on the dynamics in the human cancer cells following gamma irradiation. It is shown that the large amplification and increasing mutual information with delay are due to coherence resonance. Furthermore, frequency domain analysis is used to study the mechanisms