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21.
Taciana MF Silva Roberio G Olinda Carla MF Rodrigues Ant?nio CL Camara Francisco C Lopes Wesley AC Coelho Múcio FB Ribeiro Carlos IA Freitas Marta MG Teixeira Jael S Batista 《Veterinary research》2013,44(1):1
The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25 × 105 tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes. 相似文献
22.
Neto JO Azevedo SS Gennari SM Funada MR Pena HF Araújo AR Batista CS Silva ML Gomes AA Piatti RM Alves CJ 《Veterinary parasitology》2008,156(3-4):329-332
The prevalence and risk factors for anti-Toxoplasma gondii antibodies were investigated in goats of the Seridó Oriental microregion, Rio Grande do Norte state, Northeast region of Brazil. Three hundred and sixty-six blood samples from goats collected by jugular venopuncture were used. For the serologic diagnosis of Toxoplasma gondii infection, the indirect fluorescent-antibody test (IFAT) with cut-off value 1:64 was carried out. The prevalence of anti-T. gondii antibodies was 30.6% [95% CI=25.9-35.6%] with titers ranging from 1:64 to 1:16,384. The multivariate logistic regression analysis showed that the risk factors associated to anti-T. gondii antibodies were presence of cats in the herd, extensive/semi-intensive management systems and lack of mineral supplementation. 相似文献
23.
We determined the chromosome number of 52 accessions of Paspalum from the germplasm collection of the Centro de Pesquisa de
Pecuária do Sudeste (CPPSE/EMBRAPA) originating from different regions in Brazil. All accessions belonged to the Plicatula
group, 13 of them being P. plicatulum, three P. guenoarum, two P. yaguaronense, two P. compressifolium, one P. atratum, and
31 still unidentified Paspalum sp. Except for a P. yaguaronense accession that presented 2n=60, all the remaining ones presented
2n=40 chromosomes. This is the first report of the chromosome number of P. atratum. Considering that the basic number for
most species in the genus Paspalum is ×=10, the accessions analyzed are tetraploids (2n=4×=40) and hexaploids (2n=6×=60).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
24.
Thomas H. Galley Frederico M. Batista Richard Braithwaite Jon King Andy R. Beaumont 《Aquaculture International》2010,18(3):315-325
The blue mussel Mytilus
edulis is a commercially important species whose fishery and culture generally relies on natural spat collection. Hatchery-production
could provide an alternative source of seed, enabling reliable expansion of the industry. Mussel spawning and larval rearing
trials were carried out to optimise elements of hatchery production. Culturing fertilised eggs at low density (20–200 eggs cm−2) rather than high density (400–720 eggs cm−2) significantly improved the quality of first veliger larvae and differences in this improvement were evident between the
eggs from different females (maternal effects). Veliger larval growth at 17 or 21°C was significantly faster than growth at
14°C. Feeding veliger larvae an identical total ration either daily or at 2–3 day intervals did not significantly affect their
growth. Different microalgal diets (1: Isochrysis sp. (clone T-ISO), 2: Chaetoceros
calcitrans forma pumilus, 3: C. muelleri, 4: mixed Isochrysis sp. (clone T-ISO) and C. calcitrans f. pumilus, and 5: mixed Isochrysis sp. (clone T-ISO) and C. muelleri) were tested on veliger larval growth and mixed diets outperformed single-species diets. 相似文献
25.
Lisandra Magna Moura Rafael Silva Ramos dos Anjos Renata Oliveira Batista Naine Martins do Vale Cosme Damião Cruz José Eustáquio de Souza Carneiro Juarez Campolina Machado Pedro Crescêncio Souza Carneiro 《Euphytica》2018,214(10):181
The objectives of this study were to obtain information about genetic parameters of a partial diallel in common bean, as well as to evaluate the effects of growing seasons, locations and generations in these estimates in order to define the best strategies for the use of diallel analysis as methodology of selection of parents and populations in common bean breeding. Twelve parents were crossed in a partial diallel scheme (5?×?7), and the F1 and F2 generations were evaluated in four experiments (I, II, III, and IV). The effects of seasons were determined in the Experiments I and II, in which the F1 generation was evaluated in two distinct growing seasons. To quantify the effect of locations, we used Experiments III and IV, in which the F2 generation was evaluated in the same season, but at different locations, and to quantify the effect of generations, the experiments II (generation F1) and III (F2 generation) were evaluated in the same season and location. As for grain yield the genetic control varied according to the environment. An effect of interaction on the genetic parameters of the diallel was observed for generation, whereas for grain yield, effects of season and location were observed. For plant architecture, parental combining ability should therefore be estimated using the F1 generation, while for grain yield, both the F1 and F2 can be used. The recombination between the best hybrids is a promising strategy for extraction of superior black bean lines. 相似文献
26.
Loss of genetic variability in the captive stocks of tambaqui,Colossoma macropomum (Cuvier, 1818), at breeding centres in Brazil,and their divergence from wild populations 下载免费PDF全文
Jonas da Paz Aguiar Paola Fabiana Fazzi Gomes Igor Guerreiro Hamoy Sidney Emanuel Batista dos Santos Horacio Schneider Iracilda Sampaio 《Aquaculture Research》2018,49(5):1914-1925
The loss of variability in farmed populations and the risks of interactions with wild populations support the need for the genetic monitoring of species farmed throughout the world. In Brazil, the tambaqui is the most widely farmed native fish species. Despite this, there are no data on the pedigree of the farmed stocks, and the potential for interactions with wild populations in the Amazon basin has raised concerns with regard to the genetic variability of these stocks. The present study analysed sequences of the mitochondrial Control Region and 12 microsatellites to characterize the genetic variability of seven historically important commercial tambaqui breeding centres located in four different regions of Brazil, and compared these sequences with those obtained from individuals collected from a wild population. High levels of genetic diversity were found in the wild population, whereas genetic diversity was reduced in both markers in most captive populations, except for the broodstock located near the Amazon River. High FST and DEST indices were recorded between the wild population and most of the captive stocks analysed. The drastic reduction in genetic diversity found in most captive stocks and the difference between these stocks and the wild population may have been the result of the small size of the founding populations and the absence of breeding management. The renewal of the broodstocks and the application of breeding management techniques are recommended. In the Amazon region, in addition, the use of broodstocks that are genetically very different from local wild populations should be avoided. 相似文献
27.
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29.
Castro Liliane Araújo Andrade-Porto Sanny Maria Oliveira Rebeca Guimarães Batista Yasmin Luzeiro Silva Felipe Moura Araújo Oliveira Christiane Patrícia Feitosa Affonso Elizabeth Gusmão Cruz Claudinei Tavares-Dias Marcos 《Aquaculture International》2021,29(6):2477-2488
Aquaculture International - This study investigated the efficacy of trichlorfon against Neoechinorhynchus buttnerae, as well as its palatability, residue analysis, and the blood parameters of... 相似文献
30.
Fabieli Pelissari Anderson Cleiton José Marco Aurélio Leite Fontes Antônio César Batista Matos Wilson Vicente Souza Pereira José Marcio Rocha Faria 《New Forests》2018,49(1):143-158
Knowledge of seed desiccation tolerance is fundamental for conservation and use of forest species. The protocol used for classification of seed desiccation tolerance and storage is time consuming and many times limited by the lack of information about optimum conditions for seed germination and treatments to overcome seed dormancy. This study evaluated 66 Brazilian tree species aiming to correlate seed characteristics with desiccation tolerance. For this purpose, a model was established to explain the relationship of tegument/seed mass ratio (SCR), seed mass, and water content of embryo + endosperm with desiccation tolerance. The principal component analysis showed the establishment of two groups, indicating the interaction between desiccation tolerance and seed characteristics. Recalcitrant seeds are more often associated with the water content of embryo + endosperm and water content of tegument + endocarp, while orthodox seeds are more associated with SCR and number of seeds per kilogram. The classification found using the model proposed was significantly correlated with desiccation tolerance and storage, with 92% confidence for the analyzed species. Seeds morphological characteristics can be used for prediction of desiccation tolerance and storage behavior; however, the use of a model that combines more variables increases the chance of accurate classification. 相似文献