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The management rational of a protected area in general, the one to vocation cynegetique in particular, must rest on merely scientific bases. Information and the key information on vegetation, fauna and the ecological functions of the protected area, must be collected progressively so that they help to make assort a coh erent program of his/her/its planning. The administrators of these spaces must follow the evolution of these resources therefore regularly, and particularly to know the animal species and their movements. It is in this optics that the present survey has been undertaken in the Bay of Wali situated to the periphery of the National Park of Nouabale Ndoki in the goal to know the quality and the quantity of bi g mammals that frequent it. The present survey has been achieved during three months of January 15 to April 15, 2011 to the course of which we inventoried the big mammals in and to the periphery of the Bay of Wali. According to the results of this survey, the Bay of Wali presents a very rich, containing animal diversity thirty one (31) species different from big mammals, having preferences of very determined habitat. These preferences seem to be guided by the food needs and in mineral salts, the bodily cares and the type of plant formation. The results of the present survey could contribute to the setting up of a vast program of development of the vision tourism around the Bay of Wali and his/her/its periphery.

Five natural samples of a recent South America invader, the drosophilid Zaprionus indianus, were investigated with the isofemale line technique. These samples were compared to five African mainland populations, investigated with the same method. The results were also compared to data obtained on mass cultures of other populations from Africa and India. Three quantitative traits were measured on both sexes, wing and thorax length and sternopleural bristle number. We did not find any latitudinal trend among the American samples, while a significant increase in body size with latitude was observed in the Indian and, to a lesser degree, in the African populations. American populations were also characterized by their bigger size. Genetic variability, estimated by the intraclass correlation among isofemale lines, was similar in American and African populations. The intraline, nongenetic variability was significantly less in the American samples, suggesting a better developmental stability, the origin of which is unclear. A positive relationship was evident between intraline variability of size traits and the wing-thorax length correlation. Altogether, our data suggest that the colonizing propagule introduced to Brazil had a fairly large size, preventing any bottleneck effect being detected. The big body size of American flies suggests that they came from a high-latitude African country. The lack of a latitudinal dine in America seems to be related to the short time elapsed since introduction. The very rapid spread of Z. indianus all over South America suggests that it might rapidly invade North America.

Objectif: Ce travail, realise dans l’aulacoderie du Centre de Ressources Professionnel de Kombe de l’Institut AGRICONGO, est une contribution a l’etude de la croissance des aulacodes eleves en captivite etroite par l’utilisation de deux types de graminees fourrageres ( Penissetum purpureum et Hyparrhenia diplandra ) et de concentre. 35 aulacodes âges de 40 jours ont ete utilises. Methodologie et Resultats: Ces animaux ont ete repartis en deux groupes recevant chacun un type de fourrage. Les animaux ont ete peses par intervalle de 10 jours. Les parametres mesures sont la consommation de chaque type de fourrage et du concentre, l'indice de consommation et l’evolution du poids des aulacodes. Les resultats obtenus montrent que les deux types de fourrage utilises sont bien consommes par les aulacodes. Le fourrage de Penissetum purpureum est plus consomme que l'autre. Les valeurs obtenues sur la croissance ponderale sont tres indicatives au sevrage, a 2, 3 et 4 mois d’âge sur les deux types de fourrage. Les valeurs du coefficient de determination montrent que la croissance ponderale est fortement influencee par les consommations des deux fourrages (R²= 0,868 pour Penissetum purpureum et R²=0,911 pour Hyparrhenia diplandra ) et moyennement influencee par le (concentre (R²=0,561 et R²= 0,683). Conclusion et application des resultats: Les rations a base de fourrage de gaminees ( Penissetum purpureum , Hyparrhenia diplandra ) se trouvent etre bien valorisees dans la pratique de l’elevage des aulacodes eleves en captivite etroite dans une approche d‘etude de leur croissance en phase d’engraissement. Mots cles: Aulacodes, elevage en captivite, fourrages, concentre, croissance ponderale English Title: Growth of cane rats ( Thryonomys swinderianus Temminck , 1827) bred in captivity fed on fodder Penissetum purpureum and Hyparrhenia diplandra English Abstract Objective: This work, conducted in the aulacoderie Kombe Professional Resource Centre of the Institute AGRICONGO, is a contribution to the study of the growth of high cane rats in close captivity by the use of two types of grasses ( Penissetum purpureum and Hyparrhenia diplandra ) and concentrate. 35 cane rats aged 40 days were used. Methodology and Results: These animals were divided into two groups, each receiving a type of fodder. The animals were weighed 10 days interval. The measured parameters are the consumption of each type of fodder and concentrated feed efficiency and weight change grasscutters. The results show that both types of feed used are consumed by cane rats. Penissetum purpureum forage is consumed more than the other. The values obtained on weight gains are very indicative weaning, 2, 3 and 4 months of age on the two types of forage. The values of the coefficient of determination show that weight gain is strongly influenced by the consumption of two fodder (R² = 0.868 for Penissetum purpureum and R² = 0.911 for Hyparrhenia diplandra ) and moderately influenced by the concentrate (R² = 0.561 and R² = 0.683). Conclusion and Application of Results: The forage based rations, Grasses ( Penissetum purpureum , Hyparrhenia diplandra ) are to be valued in the practice of breeding high cane rats in captivity in the fattening phase. Keywords: cane rats, captive breeding, forage, concentrate, weight gain

Two sympatric populations of Drosophila melanogaster were collected in the Brazzaville area in Congo, one from the suburban countryside and the other from a brewery located in the city. They were compared for several genetically determined traits including morphology, allozymes, microsatellites, cuticular hydrocarbons, and sexual behaviour. The two populations were similar to other African populations for morphological traits, but differed significantly from each other for all other characters. The countryside population resembled other African populations, whereas the urban population was consistently similar to European populations. Mating choice experiments showed incipient reproductive separation between the populations. In agreement with the hypothesis that D. melanogaster originated in Africa and spread to the rest of the world by invading human-modified habitats, we suggest that man-adapted fruit fly populations have returned 'back to Africa', and remained partially isolated from older native stocks.

The objectives of this study were: (i) to test whether near infrared reflectance spectroscopy (NIRS) can be used to assess site fertility in sandy and ferralitic soils of the Congo; (ii) to evaluate the comparative advantages of this methodology with respect to classical regressions with chemical and physical analysis of soils; and (iii) to assess the ability of NIRS to predict concentrations of individual nutrients. Sixty-two plots were sampled in 20 selected forest stands with varying wood production. Site indices (Hlim) were estimated from the measured dominant height in the plots. Soil samples (N = 353) were analysed by NIRS, while physical and chemical analyses were carried out on 210 subsamples. Partial Least Squares regression (PLS) was used to model the site index from NIRS, while Variable Importance in Projection (VIP) allowed relating the main explicative frequencies to nutrient availability. A validation was performed based on an independent field trial (not used in the calibration set) in which soils were collected and analysed by NIRS. The measured dominant height growth was compared with the dominant height growth simulated from the site indices predicted using NIR spectra. Multiple regressions between site indices (Hlim) and soil properties failed to explain the variability in Hlim (R-2 = 0.36). This variability was better predicted by NIR spectra, with an R-2 = 0.64 and a predicted Root Mean Square Error of 7% for the mean value of Hlim. Based on analysis of VIP frequencies, the most important factors determining the site indices were organic matter, phosphorus, CEC, clay content, and pH. The comparison between measured and simulated dominant height in the validation set gave similar R-2 (0.61) than in the calibration set. These results demonstrate that mapping of site indices could be performed at an affordable cost in this region. The methodology developed here, which links PLS and VIP to assess the main factors determining soil fertility, is not specific to this study and could be used elsewhere. (C) 2011 Elsevier B.V. All rights reserved.

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Zaprionus indianus is a cosmopolitan drosophilid, of Afrotropical origin, which has recently colonized South America. The sexual dimorphism (SD) of body size is low, males being almost as big as females. We investigated 10 natural populations, 5 from America and 5 from Africa, using the isofemale line technique. Three traits were measured on each fly: wing and thorax length and sternopleural bristle number. Two indices of SD were compared, and found to be highly correlated (r > 0.99). For the sake of simplicity, only the female/male (F/M) ratio was further considered. A significant genetic variability of SD was found in all cases, although with a low heritability (intra-class correlation of 0.13), about half the value found for the traits themselves. For size SD, we did not find any variation among continents or any latitudinal trend, and average values were 1.02 for wing length and 1.01 for thorax length. Bristle number SD was much greater (1.07). Among mass laboratory strains, SD was genetically much more variable than in recently collected populations, a likely consequence of laboratory drift. Altogether, SD, although genetically variable and prone to laboratory drift, is independent of size variations and presumably submitted to a stabilizing selection in nature.

The plasticity of ovariole number relative to developmental temperature was studied in three populations of Drosophila melanogaster at both ends of the cline: a temperate French population and two equatorial Congolese. Ovary size was much greater in the French flies, in agreement with an already known latitudinal cline. Among isofemale lines, significant differences in genetic variability were observed between populations with a maximum variability at intermediate temperatures. Parameters of phenotypic variability (CV and FA) were not statistically different among lines or populations, but a significant increase at low temperature was demonstrated for both. The shapes of the response curves (i.e., the norm of reaction) were analyzed by adjusting the data to a quadratic equation. The parameters of the equation were highly variable among lines. On the other hand, the temperature for maximum value of ovarioles (TMV) was much less variable and exhibited only a slightly significant difference between temperate and tropical flies (22.2°C vs. 22.7°C). During its geographic extension toward colder places, D. melanogaster underwent a large, presumably adaptative, increase in ovariole number but very little change in the norm of reaction of that trait.

Alcohol dehydrogenase (Adh) (alcohol:NAD+ oxidoreductase, EC 1.1.1.1) gene frequencies and ethanol tolerance in Drosophila melanogaster are known to exhibit long-range latitudinal variations on different continents; this has led to the argument that the clines are adaptive. Accordingly, tropical populations are characterized both by a low frequency of Adh-F and by a low ethanol tolerance. In the urban area of Brazzaville (Congo) under an equatorial African climate, an original genetic structure of local populations has been found: Adh-F frequency varies from 3% to 90% when countryside and brewery populations are compared. This variation is accompanied by an increase of ethanol tolerance (from 6% to 13% alcohol). Such differences, which have remained stable for the past 3 years, were observed between collection sites less than 1 km apart. Two other enzyme loci exhibited a correlated variation with Adh-F--i.e., an increase of the S allele of glycerol-3-phosphate dehydrogenase (NAD+) (sn-glycerol-3-phosphate:NAD+ 2-oxidoreductase, EC 1.1.1.8) and of the F allele of glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate:NADP+ 1-oxidoreductase, EC 1.1.1.49). Such observations suggest very strong selective pressures exerted by environmental ethanol that oppose the gene flow due to adult dispersal between contiguous habitats. A functional relationship between the polymorphisms of the three enzyme loci seems likely, and a metabolic interaction involving NAD and NADP cofactors is proposed.

Short range genetic variations, sometimes occurring over less than a kilometer, were found at the Adh locus in natural populations from southern Spain and the Congo. Such variations seem to imply strong selective pressure exerted by environmental alcohol in cellars or in breweries. Field populations are apparently selected in an opposite direction, and the occurrence of opposite adaptive peaks seems to explain the genetic structure of samples collected. Three other enzyme loci exhibited correlated variations with Adh, i.e. Gpdh and Est-6 in Spain and Gpdh and G6pd in the Congo. By contrast, French populations are genetically homogeneous over a large area and could be considered to be a single panmictic unit. However, a release-recapture experiment of genetically marked flies suggested that the larval breeding sites in this country also correspond to small, dispersed and ephemeral patches.