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971.
ALBANO BEJA‐PEREIRA EVE ZEYL LAHOUSINE OURAGH HAMID NAGASH NUNO FERRAND PIERRE TABERLET GORDON LUIKART 《Molecular ecology resources》2004,4(3):452-455
During the last century, North African ungulate species have suffered from habitat loss and over‐hunting. Gazella dorcas (Antilopidae subfamily) and Ammotragus lervia (Caprinae subfamily) are among the ungulates that have suffered most. To help to protect these species, conservation programs and population genetics studies are being implemented. Here, we tested 30 published microsatellite primer‐pairs from Bovids (cattle, sheep and goat) on eight individuals from each species. From the 30 loci tested, 20 amplified well and showed moderate allelic richness (3.75 and 4.65 mean number of alleles per species, respectively, for G. dorcas and A. lervia), and moderatly high heterozygosity (0.53 and 0.63 per species, respectively). These 20 polymorphic markers will facilitate conservation and genetic studies in these two species, and promise to be widely useful across divergent ungulate taxa. 相似文献
972.
Gbangboche AB Glele-Kakai R Salifou S Albuquerque LG Leroy PL 《Animal : an international journal of animal bioscience》2008,2(7):1003-1012
The objectives of this study were to compare the goodness of fit of four non-linear growth models, i.e. Brody, Gompertz, Logistic and Von Bertalanffy, in West African Dwarf (WAD) sheep. A total of 5274 monthly weight records from birth up to 180 days of age from 889 lambs, collected during 2001 to 2004 in Betecoucou breeding farm in Benin were used. In the preliminary analysis, the General Linear Model Procedure of the Statistical Analysis Systems Institute was applied to the dataset to identify the significant effects of the sex of lamb (male and female), type of birth (single and twin), season of birth (rainy season and dry season), parity of dam (1, 2 and 3) and year of birth (2001, 2002, 2003 and 2004) on the observed birth weight and monthly weight up to 6 months of age. The models parameters (A, B and k), coefficient of determination (R2), mean square error (MSE) were calculated using language of technical computing package Matlab®, 2006. The mean values of A, B and k were substituted into each model to calculate the corresponding Akaike’s Information Criterion (AIC). Among the four growth functions, the Brody model has been selected for its accuracy of fit according to the higher R2, lower MSE and AIC. Finally, the parameters A, B and k were adjusted in Matlab®, 2006 for the sex of lamb, year of birth, season of birth, birth type and the parity of ewe, providing a specific slope of the Brody growth curve. The results of this study suggest that Brody model can be useful for WAD sheep breeding in Betecoucou farm conditions through growth monitoring. 相似文献
973.
Xinxin Chen Jifei Yang Yanhong Ji Edward Okoth Bin Liu Xiaoyang Li Hong Yin Qiyun Zhu 《中国病毒学》2016,31(2):150-159
African swine fever(ASF) is a lethal hemorrhagic disease that affects wild and domestic swine. The etiological agent of ASF is African swine fever virus(ASFV). Since the first case was described in Kenya in 1921, the disease has spread to many other countries. No commercial vaccines are available to prevent ASF. In this study, we generated a recombinant Newcastle disease virus(r NDV) expressing ASFV protein 72(p72) by reverse genetics and evaluated its humoral and cellular immunogenicity in a mouse model. The recombinant virus, r NDV/p72, replicated well in embryonated chicken eggs and was safe to use in chicks and mice. The p72 gene in r NDV/p72 was stably maintained through ten passages. Mice immunized with r NDV/p72 developed high titers of ASFV p72 specific Ig G antibody, and had higher levels of Ig G1 than IgG2 a. Immunization also elicited T-cell proliferation and secretion of IFN-γ and IL-4. Taken together, these results indicate that r NDV expressing ASFV p72 might be a potential vaccine candidate for preventing ASF. 相似文献
974.
Transovarial transmission of African swine fever virus in the argasid tick Ornithodoros moubata 总被引:1,自引:0,他引:1
The aim of this study was to determine filial infection prevalence of experimentally infected colony Ornithodoros moubata Walton (Ixodoidea: Argasidae) ticks for African swine fever virus (ASFV). Three groups of ticks were used: an uninfected control group, one group orally infected with the VIC T90/1 isolate and another group orally infected with the LIV 13/33 isolate of ASFV. The results show that filial infection prevalences were not constant but were highly variable between egg batches from different ticks and between successive egg batches from the same tick. Filial infection prevalences ranged from 1.8% to 31.8% for ticks infected with the VICT90/1 isolate and from 1.2% to 35.5% for ticks infected with the LIV 13/33 isolate. A similar pattern was noted after the third feed. Immunohistochemisty showed that virus replicates in the developing larval cells and not in the yolk sac cells or within the outer layers of the eggs. The results show that ASFV can replicate to a high titre (10(5.1)log10HAD50) within the larval cells of the developing egg. 相似文献
975.
Jean Maley with the collaboration of Alex Chepstow-Lusty 《Vegetation History and Archaeobotany》2001,10(2):117-120
The oil palm (Elaeis guineensis) is naturally abundant in all the African rain forests. Because this tree is a heliophytic, pioneering species, it can rapidly
colonize the periphery of the rain forest and gaps created inside, regardless of the cause. In the majority of traditional
African societies, people exploit natural oil palm groves; no attempt is made to propagate the palm by sowing or transplanting
seedlings. The late Holecene phase of dramatic forest decline, around 2500 uncal. B.P., was particularly favourable to oil
palm expansion. The scale and timing of this palaeoenvironmental variation, and the subsequent response of this pioneer tree,
cannot be interpreted as indicating human activities, let alone an indication of cultivation.
Received December 4, 2000 / Accepted March 8, 2001 相似文献
976.
G. J. Measey 《Journal of Zoology》2001,254(4):547-555
977.
Michael I. Goran Richard N. Bergman Barbara A. Gower 《Obesity (Silver Spring, Md.)》2001,9(8):423-431
Objective: To examine whether total body fat (FAT) in general or visceral fat (VFAT) in particular is associated with greater metabolic risk in white and African American children. Research Methods and Procedures: A total of 68 white and 51 African American children had measures of insulin sensitivity (Si) and acute insulin response (AIR) by a frequently sampled intravenous glucose tolerance test, total body fat by DXA and abdominal fat distribution (visceral vs. subcutaneous) by computed tomography. The influence of FAT and VFAT on insulin parameters were examined by comparing subgroups of children with high or low FAT vs. high or low VFAT and by multiple regression analysis. Results: In whites, fasting insulin, Si, and AIR were significantly influenced by FAT, but not VFAT (e.g., for Si, 9.8 ± 0.8 in low FAT vs. 4.6 ± 0.7 × 10?4/min/[μIU/mL] in high FAT, p < 0.05; 6.8 ± 0.7 in low VFAT vs. 7.5 ± 0.8 × 10?4/min/[μIU/mL] in high VFAT, p > 0.1). In African Americans, fasting insulin and Si were also primarily influenced by FAT (e.g., for Si, 4.9 ± 0.4 in low FAT vs. 2.8 ± 0.5 × 10?4/min/[μIU/mL] in high FAT, p < 0.05) but not by VFAT, and there were no significant effects of either fat compartment on AIR. In multiple regression analysis, Si was significantly influenced by FAT (negative effect), ethnicity (lower in African Americans), and gender (lower in females), whereas fasting insulin was significantly influenced by VFAT (positive effect), ethnicity (higher in African Americans), and fat free mass (positive effect). Discussion: Body fat in general is the predominant factor influencing Si, but VFAT may have additional effects on fasting insulin. The lack of major effects of VFAT on Si in children may be explained by lower levels of VFAT or because VFAT affects aspects of whole body insulin action that are not measured by the minimal model. 相似文献
978.
Luigi Boitani Iacopo Sinibaldi Fabio Corsi Alessio De Biase Ilaria d’Inzillo Carranza Maria Ravagli Gabriella Reggiani Carlo Rondinini Patrizia Trapanese 《Biodiversity and Conservation》2008,17(3):605-621
The knowledge of the areas inhabited by a species within its distribution range and the connections among patches are critical
pieces of information for successful conservation actions. The internal structure of the extent of occurrence (EO) of a species
is almost always unknown, even for “well-known” flagship species. We developed a methodology to infer the area of occupancy
(AO) within the EO of a species using the limited available data. We present here the results of a three years project funded
by European Union to develop high-resolution models of habitat suitability for 281 medium- to large-sized African mammals
across the whole continent. The existing literature was reviewed and all data on the geographic distribution and environmental
preferences of the selected species were collected. For each species, these data were then expressed in terms of key variables
available as GIS layers at a resolution of 1 km2 over the entire African continent. The AO of each species was obtained merging the information on the ecological needs of
the species and the values of ecological variables over the region identified as EO. The habitat suitability models were evaluated
through direct field work in four countries (Morocco, Cameroon, Uganda, Botswana) chosen as representatives of the environmental
and species diversity of Africa. More than 81% of models had positive true skill statistics (TSS) values, indicating models
performing better than random. Rigorous modeling procedures supported by ad-hoc field evaluation allowed the production of
high-resolution habitat suitability models useful for conservation applications. 相似文献
979.
Mallari JP Shelat A Kosinski A Caffrey CR Connelly M Zhu F McKerrow JH Guy RK 《Bioorganic & medicinal chemistry letters》2008,18(9):2883-2885
Human African trypanosomiasis (HAT) is caused by the protozoan parasite Trypanosoma brucei. The cysteine proteases of T. brucei have been shown to be crucial for parasite replication and represent an attractive point for therapeutic intervention. Herein we describe the synthesis of a series of thiosemicarbazones and their activity against the trypanosomal cathepsins TbcatB and rhodesain, as well as human cathepsins L and B. The activity of these compounds was determined against cultured T. brucei, and specificity was assessed with a panel of four mammalian cell lines. 相似文献
980.
Park Y Zhang Z Laremore TN Li B Sim JS Im AR Ahn MY Kim YS Linhardt RJ 《Glycoconjugate journal》2008,25(9):863-877
Acharan sulfate content from African giant snail (Achatina fulica) was compared in eggs and snails of different ages. Acharan sulfate was not found in egg. Acharan sulfate disaccharide →4)-α-d-GlcNpAc (1→4)-α-l-IdoAp2S(1→, analyzed by SAX (strong-anion exchange)–HPLC was observed soon after hatching and increases as the snails grow.
Monosaccharide compositional analysis showed that mole % of glucosamine, a major monosaccharide of acharan sulfate, increased
with age while mole % of galactose decreased with age. These results suggest that galactans represent a major energy source
during development, while acharan sulfate appearing immediately after hatching, is essential for the snail growth. The structures
of neutral N-glycans released from eggs by peptide N-glycosidase F (PNGase F), were next elucidated using ESI-MS/MS, MALDI-MS/MS, enzyme digestion, and monosaccharide composition
analysis. Three types of neutral N-glycan structures were observed, truncated (Hex2–4-HexNAc2), high mannose (Hex5–9-HexNAc2), and complex (Hex3-HexNAc2–10) types. None showed core fucosylation. 相似文献