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Bromatologic composition of the herbaceous species of the Northeastern Brazil Caatinga
Silva, D.S.;Andrade, M.V.M.;Andrade, A.P.;Carneiro, M.S.S.;Oliveira, J.S.;
Revista Brasileira de Zootecnia , 2011, DOI: 10.1590/S1516-35982011000400008
Abstract: the objective of this work was to evaluate the chemical composition of the pool and of four species of caatinga herbaceous vegetation in the rainy and dry seasons. the experiment was conducted in three selected shrub areas at different levels of conservation. four samples of each species (arachis pintoi, boerhavia diffusa, heliotropium ternatum, aristida adscensionis) were collected in each area and from a pool of species for determination of bromatologic composition. in the dry season, only the pool of species and the grass aristida adscensionis were evaluated. there was a significant effect of the studied area on the chemical composition of all analyzed species. the nutrient content found in the dry matter (dm) and the digestibility of the pool of species indicate that caatinga herbs presented improved quality in the rainy season. the qualitative variables of the studied species were most heterogeneous due to the variability found in caatinga. conservation conditions in caatinga and season of the year influence bromatologic composition of the species arachis pintoi, boerhavia diffusa l., heliotropium ternatum vahl. aristida adscensionis l. and of a pool of typical species found in caatinga.
Forage supply in thinned Caatinga enriched with buffel grass (Cenchrus ciliaris L.) grazed by goats and sheep
Formiga, Luiza Daiana Araújo da Silva;Pereira Filho, José Morais;Silva, Aderbal Marcos de Azevêdo;Oliveira, Nadjanara Souza;Soares, Diogo da Costa;Bakke, Olaf Andreas;
Acta Scientiarum. Animal Sciences , 2012, DOI: 10.4025/actascianimsci.v34i2.12548
Abstract: forage supply from herbs was assessed in a thinned caatinga enriched with buffel grass (cenchrus ciliaris l.) exposed to goat and sheep grazing. the 2.4 ha experimental area, located at the experimental station of the federal university of campina grande, in santa terezinha, paraíba state, brazil, was divided into four 0.6 ha paddocks, which were further subdivided into two 0.3 ha experimental plots. twelve f1 (boer x srd) goats and 12 santa inês sheep were divided in four groups of six animals of the same species. the herbaceous vegetation was separated into buffel grass (cenchrus ciliaris l.), dicotyledons and other grass species. treatments were randomized to plots according to a completely random design with two treatments, four replications, with measures repeated in time (july/1, aug/1, sept/1 and oct/1. buffel grass dry mater (dm) availability was higher in the sheep grazed than in the goat-grazed area. buffel grass dm supply did not change from july to september, while dicotyledons dm supply decreased. grazing affected availability, accumulation rate and supply of the forage produced (dm basis) by dicotyledonous herbs. buffel grass forage availability was not affected during the experimental period.
Inter-annual variations in the floristic and population structure of an herbaceous community of "caatinga" vegetation in Pernambuco, Brazil
Reis, Ana Maria S.;Araújo, Elcida L.;Ferraz, Elba Maria N.;Moura, Ariadne N.;
Brazilian Journal of Botany , 2006, DOI: 10.1590/S0100-84042006000300017
Abstract: the influence of climatic variations on the herbaceous component of the "caatinga" vegetation was examined in the state of pernambuco, brazil. a total of 105 1 × 1 m-plots were established, of which 35 were in a level micro-habitat, 35 in a riparian micro-habitat, and 35 in a stony microhabitat. during two consecutive years all herbaceous plants in these plots were counted, measured (height and diameter), and collected for identification. the shannon-wiener diversity index and the equitability were calculated for each year, as well as the density, frequency, dominance, total basal area and importance index for each species. the total annual pluviometric was 819.5 and 448.8 mm in 2002 and 2003, respectively. the herbaceous flora in the study area was composed of 71 species, of which 58 were sampled in the plots. the families with the greatest species richness were malvaceae (8 species), euphorbiaceae (7), poaceae (6), convolvulaceae (4), fabaceae (4), and portulacaceae (4). the diversity indices were 2.66 and 3.01 nats ind-1 in 2002 and 2003, respectively. the density, frequency, dominance and importance value of herbaceous populations, as well as, the height and diameter of plants were low in the dryer year. the riparian group was the most isolated of the microhabitats examined, both in terms of its floristic and its population structure. annual seasonal climatic variations greatly modified these populations structure during the course of this study, emphasizing the fact that long-term studies are needed in order to better understand the dynamics of the herbaceous component of the "caatinga" vegetation.
Potential of Caatinga forage plants in ruminant feeding
Santos, Mércia Virginia Ferreira dos;Lira, Mário de Andrade;Dubeux Junior, José Carlos Batista;Guim, Adriana;Mello, Alexandre Carneiro Le?o de;Cunha, Márcio Vieira da;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010001300023
Abstract: caatinga is the most important biome for the livestock in the brazilian semi-arid region. this review paper aimed to present information on different forage aspects of caatinga vegetation for ruminant feeding. caatinga vegetation is formed mainly by shrubs and small trees, usually presenting thorns, deciduous leaves, and leaf abscission occurring frequently at the onset of the dry season. additional components of the botanical composition in this biome includes the families cactaceae, bromeliaceae, and a herbaceous component formed by grasses, legumes, and forbs, often presenting annual cycle. quantitative information of caatinga vegetation is scarce in the literature, mainly for the herbaceous stratum. methodological aspects such as lack of standardization across evaluations make comparison regarding forage potential of caatinga plant species difficult. index species must be identified within each caatinga type. quantitative aspects of biological n2 fixation by caatinga species have not been extensively studied. regarding forage nutritive value, it is necessary to study n availability for ruminants in caatinga plants, since large proportion of this element may bind to fiber components (adin). manipulation of caatinga vegetation is an alternative to change forage quantity and quality for grazing animals, affecting their performance as a result. studies measuring qualitative and quantitative variability of native forage resources from caatinga are mandatory in order to improve animal feeding management, with the ultimate goal of creating sustainable animal production based on caatinga vegetation.
Characterization of indigenous rhizobia from Caatinga
Teixeira, Fernanda Cíntia Pires e;Borges, Wardsson Lustrino;Xavier, Gustavo Ribeiro;Rumjanek, Norma Gouvêa;
Brazilian Journal of Microbiology , 2010, DOI: 10.1590/S1517-83822010000100029
Abstract: the aim of this study was to characterize rhizobial isolates from cratylia mollis mart. ex benth, calliandra depauperata benth. and mimosa tenuiflora (willd.) poir. by means of rhizobial colonies morphology and restriction analysis of the 16s ribosomal gene (16s rdna-ardra). nodules were collected in the field and from plants cultivated in a greenhouse experiment using caatinga soil samples. sixty seven isolates were described by morphological analysis. forty seven representative isolates were used for ardra analysis using seven restriction enzymes. we observed high diversity of both slow and fast-growing rhizobia that formed three morpho-physiological clusters. a few fast-growing isolates formed a group of strains of the bradyrhizobium type; however, most of them diverged from the b. japonicum and b. elkanii species. cratylia mollis nodule isolates were the most diverse, while all mimosa tenuiflora isolates displayed fast growth with no ph change and were clustered into groups bearing 100% similarity, according to ardra results.
Polyembryony in angiospermous trees of the Brazilian Cerrado and Caatinga vegetation
Salom?o, Antonieta N.;Allem, Antonio C.;
Acta Botanica Brasilica , 2001, DOI: 10.1590/S0102-33062001000300007
Abstract: the occurrence of polyembryony was investigated in 75 woody species of the cerrado in central brazil and the xerophilous caatinga vegetation in northeastern brazil. fourteen species showed polyembryony, a type of anomalous angiospermous reproduction. polyembryony is reported for the first time for nine genera, astronium, byrsonima, cariniana, copaifera, hancornia, magonia, myracrodruon, tabebuia, and tapirira. the positive correlation found between polyembryony, sexual reproduction, and apomictic processes suggests that a number of angiospermous species may make regular use of multiple breeding systems.
Polyembryony in angiospermous trees of the Brazilian Cerrado and Caatinga vegetation  [cached]
Salom?o Antonieta N.,Allem Antonio C.
Acta Botanica Brasilica , 2001,
Abstract: The occurrence of polyembryony was investigated in 75 woody species of the Cerrado in central Brazil and the xerophilous Caatinga vegetation in northeastern Brazil. Fourteen species showed polyembryony, a type of anomalous angiospermous reproduction. Polyembryony is reported for the first time for nine genera, Astronium, Byrsonima, Cariniana, Copaifera, Hancornia, Magonia, Myracrodruon, Tabebuia, and Tapirira. The positive correlation found between polyembryony, sexual reproduction, and apomictic processes suggests that a number of angiospermous species may make regular use of multiple breeding systems.
Reproductive Biology of Bothrops erythromelas from the Brazilian Caatinga  [PDF]
Ver?nica Alberto Barros,Claudio Augusto Rojas,Selma Maria Almeida-Santos
Advances in Zoology , 2014, DOI: 10.1155/2014/680861
Abstract: The reproductive biology of Bothrops erythromelas, a small pit viper from the Caatinga, a semiarid biome in Brazil, is described based on analysis of individuals deposited in zoological collections. Males are smaller and also attain sexual maturity at a smaller size than females. Female reproductive cycle is seasonal with an extended period of secondary vitellogenesis and births occurring in a restricted period from late spring to early summer. Sperm storage in females may probably occur in infundibular tubular glands and uterine muscular twisting (UMT), which is a polymorphic condition within B. erythromelas. Seasonal spermatogenesis in males is variable with some intraspecific variation regarding the male reproductive stage per season. Most males are reproductively active during spring/summer and reproductively quiescent during autumn/winter, although some individuals vary (e.g., show testicular spermatogenesis and active sexual segment of the kidneys (SSK) during winter). The SSK could be identified in every male. Most males showed highly hypertrophied SSK in spring/summer and moderately hypertrophied SSK in autumn/winter. The ampulla ductus deferentis was observed and histochemical reactions were conducted. We discuss the probable influence of the unique environmental conditions of the Caatinga region and phylogenetic inertia in the reproductive patterns of this snake species. 1. Introduction The Caatinga domain, a mosaic of thorny bushes and seasonal dry forest, is a semiarid biome exclusive to Brazil. It is characterized by an extremely irregular rainfall pattern with severe dry seasons in some years [1]. Reptiles that live in arid environments may show physiological, behavioral, ecological, and morphological adaptations related to water scarcity in the environment [2]. Recently, a long-term study in the field showed that timing of parturition is influenced by rainfall seasonality in Crotalus atrox, a pit viper species from the Sonoran Desert [3]. To our knowledge, few studies addressed questions related to the influence of rainfall in the determination of reproductive strategies in snakes [3, 4]. Pit viper species from the Caatinga region are good models to explore questions on the influence of environmental variables in the reproductive cycles because this region has unique characteristics regarding patterns of temperature and rainfall [1], and some data on reproduction of pit viper species from the Neotropical region including species from the Caatinga region are available for comparisons [4–9]. Bothrops erythromelas is a terrestrial and
Curvas de crescimento para caprinos da ra a Anglo-Nubiana criados na caatinga: rebanho de elite e comercial Growth curve in Anglo-Nubian goats raised in caatinga: nucleus herd and commercial herd  [cached]
Carlos Henrique Mendes Malhado,Paulo Luiz Souza Carneiro,Jurandir Ferreira da Cruz,Divane Fernandes de Oliveira
Revista Brasileira de Saúde e Produ??o Animal , 2008,
Abstract: Os objetivos neste estudo foram analisar modelos n o-lineares para descrever o crescimento em caprinos da ra a Anglo-Nubiana na caatinga, oriundos de rebanho elite e comercial, e, após a defini o do modelo de melhor ajuste, calcular a taxa de crescimento absoluto e avaliar a influência de fatores ambientais (rebanho, tipo de parto e sexo) sobre os parametros da curva de crescimento. O rebanho elite foi constituído por animas puros de origem (PO) criados em sistema semi-intensivo de manejo. O rebanho comercial foi formado por animais criados no sistema tradicional da caatinga. Os modelos n o-lineares utilizados foram: Brody, Von Bertalanffy, Richards, Logístico e Gompertz. O modelo Von Bertalanffy apresentou o melhor ajuste. Os animais do rebanho comercial s o mais precoces e de menor peso adulto em compara o aos PO submetidos à cria o semi-extensiva. O tipo de rebanho e o sexo influenciaram significativamente (P<0,01) o peso assintótico (A). A taxa de crescimento (k) n o foi influenciada (P>0,05) pelos efeitos analisados. As correla es estimadas entre os parametros A e k foram negativas e iguais a -0,76 e -0,61 para o rebanho elite e comercial, respectivamente, indicando que os animais mais precoces possuem menor probabilidade de atingirem pesos elevados à idade adulta. The goal of this study was to evaluate the application of non-linear models in Anglo-Nubian goats on nucleus herd and commercial herd, both raised in the caatinga. After defining the best-adjusted model, the rate of absolute growth and the influence of environmental traits (breed, type of parturing and sex) on curve parameters were studied. The nucleus herd was composed of purebred animals (PO) raised under semi-intensive conditions. The commercial herd comprised animals raised under the traditional management system in caatinga. The non-linear models used were: Brody, Von Bertalanffy, Richards, Logistic and Gompertz. The Von Bertalanffy model presented the best adjustment. The animals from the commercial line are more precocious and present lower weights when adults than PO animals, semi-intensively raised. The type of breed and sex have significantly influenced (P<0.01) the asymptotic weight (A). The analyzed effects did not influence the growth rate (k) (P>0.05). The estimated correlation values between the parameters A and k were negative and equal to -0.76 and -0.61 for the nucleus herd and commercial herd, respectively, indicating that more precocious animals are less likely to reach higher weights when adults.
Richness of gall-inducing insects in the tropical dry forest (caatinga) of Pernambuco
Santos, Jean Carlos;Almeida-Cortez, Jarcilene Silva de;Fernandes, G. Wilson;
Revista Brasileira de Entomologia , 2011, DOI: 10.1590/S0085-56262011000100009
Abstract: diversity of gall-inducing insects in the tropical dry forest (caatinga) of pernambuco. we report on the richness of galling insects in the vegetation of caatinga of pernambuco state, brazil. we recorded 64 different types of galls collected primarily from leaves and stems of 48 species of host plants belonging to 17 families and 31 genera. the most common gall morphological types were spheroid and discoid, glabrous, predominantly green and with one chamber. the main gall inducing taxon was the cecidomyiidae (diptera). the results of this study contribute to existing knowledge of galling insect and host-plant diversity in caatinga.
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