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991.
Michalsky EM Rocha MF da Rocha Lima AC França-Silva JC Pires MQ Oliveira FS Pacheco RS dos Santos SL Barata RA Romanha AJ Fortes-Dias CL Dias ES 《Veterinary parasitology》2007,147(1-2):67-76
Visceral leishmaniasis (VL) is a growing zoonosis with an increasing number of new cases and a rapid geographical spreading of the disease. In the present study, a canine survey was carried out in the city of Montes Claros (320,000 inhabitants), an endemic area of American visceral leishmaniasis in the state of Minas Gerais, Brazil. A total number of 4795 dogs were examined by serology, which showed a rate of seropositivity of 5%. Isoenzymatic analysis confirmed Leishmania infantum chagasi as the local aetiological agent of CVL. Canine tissues were assayed for the presence of Leishmania parasite DNA using different techniques. The infectivity of asymptomatic, oligosymptomatic and symptomatic seropositive dogs was tested by xenodiagnosis using laboratory reared Lutzomyia longipalpis. Rates of infection of 5.4%, 5.1% and 28.4% were found for the phlebotomine sand flies that fed in asymptomatic, oligosymptomatic and symptomatic dogs, respectively. Our results indicate that, under experimental conditions, symptomatic dogs are about four times more infective to VL vectors than oligosymptomatic or asymptomatic animals. The lower infectivity rates of dogs displaying any of the last two clinical forms of leishmaniasis, however, must be taken into account in the epidemiology of CVL. 相似文献
992.
Ramajo-Hernández A Oleaga A Ramajo-Martín V Pérez-Sánchez R 《Veterinary parasitology》2007,144(1-2):45-60
Schistosoma bovis is a parasite of wild and domestic ruminants that is broadly distributed throughout many tropical and temperate regions of the old world. S. bovis causes severe health problems and significant economic losses in livestock, but in contrast to human schistosomes, S. bovis has been little investigated at a molecular level. Since schistosome glycans and glycoproteins can play important roles in the host-parasite interplay, the aims of the present work were: (i) to characterize the glycans expressed by adult S. bovis worms on their excreted/secreted (ES) and tegumental (TG) glycoproteins and (ii) to identify their carrier protein backbones by mass spectrometry. Using a panel of lectins and monoclonal and polyclonal anti-glycan antibodies, we observed: (i) the absence of sialic acid in S. bovis; (ii) the presence of complex-type N-glycans and LDN antennae on ES glycoproteins; (iii) the presence of glycans containing the Fucalpha1-2Galbeta motif in many TG glycoproteins, and (iv) the presence of glycans containing the Fucalpha1-3GlcNAc motif on many ES and TG glycoproteins but, simultaneously, the absence of the F-LDN(-F) glycans from both the ES and TG glycoproteins. Interestingly, we also found the Lewis(X) and Lewis(Y) antigens co-expressed on several TG isoforms of ATP:guanidino kinase and glyceraldehyde-3-phosphate dehydrogenase. Finally, by ELISA we observed the presence of antibodies against Lewis(X), Lewis(Y) and F-LDN(-F) in the sera of sheep experimentally infected with S. bovis. 相似文献
993.
Baffi MA de Souza GR Vieira CU de Sousa CS Gourlart LR Bonetti AM 《Veterinary parasitology》2007,148(3-4):301-309
Chemical control based on the use of pyrethroid and organophosphate compounds has selected resistant genotypes in populations of Rhipicephalus (Boophilus) microplus. Point mutations in esterase-encoding genes represent one of the main resistance mechanisms in this species. In this study, the PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) technique was used to investigate the presence of mutations in a fragment of a putative carboxylesterase in a population of ticks with a history of resistance. The digestion of a fragment of 372 pb with EcoRI revealed three genotypes: W, H and M, observed in different frequencies. The homozygous wild-type genotype (W) was detected only in sensitive strains, with high frequency. The heterozygous genotype (H) was observed in all the strains, albeit with higher frequency in the strains with a moderate resistance, while the homozygous mutant genotype (M) was found only in the moderate resistant strain and resistant strains, with higher frequency in the resistant strains. A comparison of the sequences indicated the presence of other mutations, besides EcoRI polymorphism in the moderate resistant and resistant strains. Also found was the presence of stop codons generating truncated proteins in the sensitive and moderate resistant strains. A domain analysis revealed the presence of additional domains in the resistant strain. These findings suggest that different point mutations, as well as the influence of post-translational modification mechanisms, are altering the activity of the translated proteins and may be associated with resistance. 相似文献
994.
Schipper J Chanson JS Chiozza F Cox NA Hoffmann M Katariya V Lamoreux J Rodrigues AS Stuart SN Temple HJ Baillie J Boitani L Lacher TE Mittermeier RA Smith AT Absolon D Aguiar JM Amori G Bakkour N Baldi R Berridge RJ Bielby J Black PA Blanc JJ Brooks TM Burton JA Butynski TM Catullo G Chapman R Cokeliss Z Collen B Conroy J Cooke JG da Fonseca GA Derocher AE Dublin HT Duckworth JW Emmons L Emslie RH Festa-Bianchet M Foster M Foster S Garshelis DL Gates C Gimenez-Dixon M Gonzalez S 《Science (New York, N.Y.)》2008,322(5899):225-230
Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action. 相似文献
995.
Canul-Solis Jorge Angeles-Hernandez Juan Carlos García-Herrera Ricardo A. del Razo-Rodríguez Oscar Enrique Lee Rangel Héctor A. Piñeiro-Vazquez Angel T. Casanova-Lugo Fernando Rosales Nieto Cesar A. Chay-Canul Alfonso J. 《Tropical animal health and production》2020,52(5):2341-2347
Tropical Animal Health and Production - The aim of the present study was to develop and evaluate an equation to predict body weight (BW) using hip width (HW) in Pelibuey ewe lambs and ewes. Five... 相似文献
996.
Pinheiro Jessyca Karen Ferreira Raimundo Ribeiro Gonzaga Neto Severino Signoretti Ricardo Dias Henriques Lara Toledo de Oliveira Juliana Silva 《Tropical animal health and production》2020,52(3):1309-1314
Tropical Animal Health and Production - The present study aimed to evaluate the degradation dynamics of high-quality tropical forage according to the levels of nitrogen supplementation. In this... 相似文献
997.
998.
999.
Gabriel Soares Campos Bruna Pena Sollero Fernando Antonio Reimann Vinicius Silva Junqueira Leandro Lunardini Cardoso Marcos Jun Iti Yokoo Arione Augusti Boligon José Braccini Fernando Flores Cardoso 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(5):449-467
The aim of this study was to perform a Bayesian genomewide association study (GWAS) to identify genomic regions associated with growth traits in Hereford and Braford cattle, and to select Tag-SNPs to represent these regions in low-density panels useful for genomic predictions. In addition, we propose candidate genes through functional enrichment analysis associated with growth traits using Medical Subject Headings (MeSH). Phenotypic data from 126,290 animals and genotypes for 131 sires and 3,545 animals were used. The Tag-SNPs were selected with BayesB (π = 0.995) method to compose low-density panels. The number of Tag-single nucleotide polymorphism (SNP) ranged between 79 and 103 SNP for the growth traits at weaning and between 78 and 100 SNP for the yearling growth traits. The average proportion of variance explained by Tag-SNP with BayesA was 0.29, 0.23, 0.32 and 0.19 for birthweight (BW), weaning weight (WW205), yearling weight (YW550) and postweaning gain (PWG345), respectively. For Tag-SNP with BayesA method accuracy values ranged from 0.13 to 0.30 for k-means and from 0.30 to 0.65 for random clustering of animals to compose reference and validation groups. Although genomic prediction accuracies were higher with the full marker panel, predictions with low-density panels retained on average 76% of the accuracy obtained with BayesB with full markers for growth traits. The MeSH analysis was able to translate genomic information providing biological meanings of more specific gene products related to the growth traits. The proposed Tag-SNP panels may be useful for future fine mapping studies and for lower-cost commercial genomic prediction applications. 相似文献
1000.
Hudson H. V. Correia Laritza F. Lima Francisca Geovania C. Sousa Anna Clara A. Ferreira Jesus Cadenas Victor M. Paes Benner G. Alves Ariella Shikanov José Ricardo Figueiredo 《Reproduction in domestic animals》2020,55(1):105-109
The present study aimed to evaluate the effect of three culture systems on caprine primordial follicle activation in vitro: follicles cultured either in the isolated form within alginate (Isolated follicles + Alginate treatment), or enclosed in ovarian tissue (in situ), with or without alginate (Fragment + Alginate, and Fragment alone treatments, respectively). After culture, the Isolated follicles + Alginate treatment presented a percentage of morphologically normal follicles (MNF) similar to both the non-cultured control and the Fragment Alone treatments. Nevertheless, Fragment + Alginate treatment showed a significant reduction in the number of MNF when compared to the other treatments. Regarding follicle development, our results showed that regardless of the alginate, the presence of ovarian tissue limited primordial follicle activation during in vitro culture. Remarkably, the Isolated primordial follicle + Alginate treatment was the only one that significantly promoted follicle activation and increased both follicle and oocyte diameters during IVFC, pointing out a higher cell proliferation. In conclusion, the presence of ovarian tissue with or without alginate limited follicle development (activation) after culture. Nevertheless, when primordial follicles were isolated and encapsulated in alginate they presented suitable survival rates, higher rates of follicle activation and continued to grow throughout the culture period. 相似文献