Abstract:
:Specimens of the characid Brycinus nurse (N = 980) were collected in Asa reservoir, Nigeria, from November 1991 to October 1993. The diet was analyzed from stomach contents using the frequency of occurrence, numerical and gravimetric methods. Fish sex affected occurrence, number and weight of food items. The relative importance index (RI) indicates that diet varied seasonally. There was also a noticeable switch from insectivorous habits in small fish (less than 18 cm) to herbivorous feeding habits in larger fish. The ability of the fish to evolve trophic strategies that ensure optimum foraging despite seasonal changes can account for its success in the lake.
journal_name
Rev Biol Tropjournal_title
Revista de biologia tropicalauthors
Saliu JKsubject
Has Abstractpub_date
2002-03-01 00:00:00pages
233-8issue
1eissn
0034-7744issn
2215-2075journal_volume
50pub_type
杂志文章abstract::Simplification of natural habitats leads to a modification of the community associated with a host plant. Pequi trees (Caryocar brasiliense) are common to find in central Brazil, especially in the middle of monocultures, such as soy, corn, pasturelands or Eucalyptus plantations. On this scenario we hypothesized that h...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v60i3.1758
更新日期:2012-09-01 00:00:00
abstract::Abstract: Attacks by big cats on livestock are one of the major causes of human-felid conflicts and, therefore, an important factor in the conservation of these species. It has been argued that a reduction in natural prey abundance promotes attacks on domestic species, but few studies have tested this statement, and s...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v62i4.13199
更新日期:2014-12-01 00:00:00
abstract::We examined the protoplasmic assimilation of columnar cacti pollen grains in two species of Venezuelan desert glosophagine bats, Glossophaga longirostris and Leptonycteris curasoae, by determining the amount of empty (digested) pollen grains found in their fecal samples. To determine the amount of empty pollen grains,...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2005-03-01 00:00:00
abstract::Paternal behavior and testosterone plasma levels in the Volcano Mouse Neotomodon alstoni (Rodentia: Muridae). Although initially it was thought that testosterone inhibited the display of paternal behavior in males of rodents, it has been shown that in some species high testosterone levels are needed for exhibition of ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v57i1-2.11360
更新日期:2009-03-01 00:00:00
abstract::Actually, the germplasm of Jatropha spp. is conserved as whole plants in field collections. Under this storage method, the genetic resources are exposed to disease, pest and natural hazards such as human error, drought and weather damage. Besides, field genebanks are costly to maintain and with important requirements ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v60i1.2782
更新日期:2012-03-01 00:00:00
abstract::A sample of 15 Costa Rican scientific papers published since 1985 reported only 49% of the necessary information about laboratory animals and experimental conditions, slightly better than in the rest of Latin America (47%, sample = 15 papers) but lower than in the USA and Europe (60%, sample = 15). Adequate informatio...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:1997-09-01 00:00:00
abstract::Estimating feline abundance becomes particularly difficult, sometimes impossible, due to their elusive behavior and extensive space requirements. Available techniques are expensive and/or poorly efficient, therefore alternative methods are needed. The objective of this study was to assess the possibility of identifyin...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2008-12-01 00:00:00
abstract::We observed the mating behavior of the neck-banded snake Scaphiodontophis annulatus (a common species of colubrid in the South Pacific of Costa Rica) in the pre-montane wet forest of Las Cruces Biological Station (San Vito de Java, Costa Rica). Three S. annulatus were observed during courtship between 10-12 AM in a pa...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v54i2.13940
更新日期:2006-06-01 00:00:00
abstract::Biomarkers are a widely applied approach in environmental studies. Analyses of cholinesterase (ChE), glutathione S-transferase (GST) and lipid peroxidation (LPO) are biomarkers that can provide information regarding early effects of pollutants at different biochemical levels on an organism. The aim of this study was t...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v60i1.2769
更新日期:2012-03-01 00:00:00
abstract::Plant regeneration from seven-week-old callus cultures derived from mature embryos of several indica rice cultivars was achieved with frequencies of morphogenic calli from 10 to 47%. Three media were tested both for callogenesis and plant regeneration. For 3 of the 7 genotypes examined, the best combination of media f...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:1997-03-01 00:00:00
abstract::Abstract: Histology of gill, liver and kidney in juvenile fish Colossoma macropomum exposed to three temperatures. Water temperature is an important factor that affects growth and antioxidant enzyme activities in fish, and when adverse, it may trigger diseases in fish populations. C. macropomum is a freshwater neotrop...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2013-06-01 00:00:00
abstract::Occurrence of the bacterium Helicobacter pylori was compared for two Costa Rican sites with contrasting levels of gastric cancer incidence, Poás (incidence 15.13%) and Puriscal (83.53%). A sample of 185 adults of similar age and sex proportions was studied in each site, using both H. pylori antiserum tests and gastros...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:1998-09-01 00:00:00
abstract::Production and condition index of a turkeywing (Arca zebra) population were studied from August 1984 to August 1985 in Pariche, Cariaco Gulf, Venezuela. Production was studied through bimonthly collections using a method designed for populations with continuous reproduction and indistinguishable age classes. The popul...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2001-06-01 00:00:00
abstract::Thirteen representatives of Myxariaceae sensu Jülich: Heterochaetella brachyspora (Bourdot & Galzin) Luck-Allen, Myxarium atratum (Peck) Ginns & Lefebvre, M. granulum Hauersl., M. laccatum (Bourdot & Galzin) Reid, M. mesomorphum (Bourdot & Galzin) Haursl., M. mesonucleatum Kisim., Oberw. & L.D. Gómez nov. sp., M. subs...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2000-06-01 00:00:00
abstract::Liolaemus belongs to the Eulaemus subgenus, that is included in the Liolaemus montanus group or section, and is distributed in Argentina, Bolivia, Chile and Peru. The species members of this clade inhabit arid and high altitude environments, usually above 2800 m, and have a strong tendency to herbivory and a viviparou...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2013-12-01 00:00:00
abstract::Rhizosphere microbial communities are important for phytoremediation, plant nutrition, health and metabolism. Many factors, including plant species, pH and nutritional factors influence rhizosphere micro- biology. In this study, we analysed the effects of different forms of nitrogen on the structures of rhizosphere ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v64i1.18138
更新日期:2016-03-01 00:00:00
abstract::The study presents an interactive descriptive tool (MONRATE) for calculating and predicting reinfection rates and time of Ascaris lumbricoides following mass chemotherapy. The implementation was based on the theoretical equation published by Hayashi in 1977, for time-prevalence: Y=G [1-(1-X)(N-R)] as modified by Jong-...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v55i3-4.5951
更新日期:2007-09-01 00:00:00
abstract::The fish and invertebrates community structure in the Sabancuy estuary was analyzed in two seasons and 14 sampling stations (13 along the estuary and one in the marine adjacent coast). No significant differences were found between seasons. The environmental frame defines two zones within the estuary, the first extends...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2001-03-01 00:00:00
abstract::The dose dependent antiproliferative effect of an alkaloidal substance extracted from the sponge Amphimedon viridis was tested on Leishmania mexicana promastigotes. Sponges were collected in Isla Larga, Venezuela (10 degrees 20' 20" - 10 degrees 24" N, 64 degrees 19' - 64 degrees 22' W), cut and dipped in methanol for...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2000-12-01 00:00:00
abstract::Cattleya trianae is an endemic species from the tropical rainforest in the Colombian Andes. Its survival is currently threatened due to habitat loss and commercial overexploitation. This study evaluates ten substrates, some organic (pine bark, coconut fiber and wood shavings), some inert icopor (polystyrene foam), veg...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v55i2.6045
更新日期:2007-06-01 00:00:00
abstract::The development of the prothallia in nine species of Callipteris Bory (Woodsiaceae), four species of Diplazium, the genus from which Callipteris has been segregated, and one species of Dryoathyrium are studied in this paper. The data obtained are compared with the development of the prothallia of several other genera ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章,评审
doi:
更新日期:2003-03-01 00:00:00
abstract::The diet ofa neotropical fish species (Creagrutus bolivari) was studied using different methods: the Cortés 1997 graphic method and two relative importance indexes, one designed by George and Hadley in 1979 (% RIi) and another proposed by Cortés in 1997 (% IRIi). Only discrete prey (aquatic and terrestrial invertebrat...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2006-12-01 00:00:00
abstract::An avirulent T. gondii strain isolated from a owl (Glaucidium brasilianum) produces randomly distributed cysts in the brain of mice which can survive to inocula as high as 1000 oocysts. Cysts appeared for the first time after 15 days of infection. Regarding to humoral immunity development due to our TCR-2 strain, dete...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:1990-11-01 00:00:00
abstract::The Mato Grosso is a typical Atlantic Forest stream located on the East coast of Brazil, approximately 70 km from Rio de Janeiro city. From its source at about 800m a.s.l, the stream drains a 30km2 area of the Northwestern part of the municipality of Saquarema, state of Rio de Janeiro and flows into the Saquarema Lago...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v58i4.5425
更新日期:2010-12-01 00:00:00
abstract::The anti-inflammatory properties of Loasa speciosa and Loasa triphylla (Loasaceae), Urtica leptuphylla and Urera baccifera (Urticaceae), and Chaptalia nutans (Asteracene) were studied using the carregeenan induced rat paw edema model. Aqueous extracts of each plant were made according to the ethnobotanical use. The hi...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract::The coastal lagoons of Veracruz, Gulf of Mexico, include a great variety of biological resources. These resources, especially fish communities, have been barely described and that require more ecological studies. With this aim, this investigation analyzed the spatial and temporal variation of diversity, abundance and ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2014-03-01 00:00:00
abstract::The queen conch Eustrombus gigas is an important fisheries resource in the Caribbean region. In Cuba Island the studies about this resource are very scarce and particularly in the Southeastern regions of the country. With the aim to get important fishery information about this gastropod, adult Queen Conch density and ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v61i2.11165
更新日期:2013-06-01 00:00:00
abstract::Schistosomiasis remains a disease of major global public health concern since it is a chronic and debilitating illness. The widely distributed Schistosoma mansoni that causes intestinal schistosomiasis represents a great threat. Its world-wide distribution is permitted by the broad geographic range of the susceptible ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v64i4.21668
更新日期:2016-12-01 00:00:00
abstract::Turbinella angulata and Busycon perversum are two marine gastropods that support the 90% of conch fisheries in the Gulf of Mexico, nevertheless there is no information available to support a management strategy for both species. The aim of this work was to obtain preliminary fishery information to promote management a...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2013-03-01 00:00:00
abstract::A systematic list of the echinoderms of the Gulf of California, based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. A ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2005-12-01 00:00:00