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561.
Jenevaldo Barbosa da Silva Charles Passos Rangel Adivaldo Henrique da Fonseca Eziquiel de Morais Wagner Marcelo Souza Vinhote Danillo Henrique da Silva Lima Natália da Silva e Silva José Diomedes Barbosa 《Tropical animal health and production》2014,46(2):385-389
To evaluate the prevalence and possible risk factors for brucellosis caused by Brucella abortus in water buffaloes in the state of Pará, Brazil, 3,917 female buffalo serum samples from pregnant and non-pregnant animals were examined: 2,809 from Marajó Island and 1,108 from the mainland. The buffered acidified plate antigen (BAPA) screening test positively diagnosed 4.8 % (188/3,917) of the animals with brucellosis, and the 2-mercaptoethanol (2-ME) confirmatory test affirmed 95.7 % (180/188) of the results. The brucellosis prevalence was 4.17 times greater in mainland animals than on Marajó Island, with the highest prevalence in Tailândia (11.30 %) and Paragominas (12.38 %). Brucellosis seroprevalence was significantly influenced (p?<?0.05) by reproductive status, with pregnant females being most vulnerable. These results demonstrate that brucellosis infection is active in the Brazilian region containing the largest buffalo population and that this disease poses a threat to public health and buffalo production in Pará. 相似文献
562.
Felipe Pratalli Martins Erick Candiota Souza Fernanda Coelho Simas Bernardes Marcelo Abidu-Figueiredo Carlos Benhur Kasper Paulo de Souza-Junior 《Anatomia, histologia, embryologia》2021,50(1):212-217
Anatomical variation in wild canids is rarely described. Altered shapes, uni- or bilaterally situated, were observed in ventral laminae of C6 and/or in C7 vertebral body of two fox species: Lycalopex gymnocercus and Cerdocyon thous. The specimens were young adults, collected dead on highways in southern Brazil. Deformities were considered anatomical variations because apparently there was no interference in function. The occurrence of such variations in two related species from the same area can suggest an environmental common cause rather than genetic issues. Future studies may deepen the understanding between cause and effect of these vertebral deformities in wild canids. 相似文献
563.
Marcelo F.G. Boriollo Bianca S. Moreira Mateus C. Oliveira Taiane O. Santos Luciana R.A. Rufino Nelma M.S. Oliveira 《Canadian journal of veterinary research》2021,85(1):18
The aim of this study was to evaluate the occurrence of Shiga toxin (stx)-producing Escherichia coli (STEC) in diarrheic newborn calves, as well as the resistance profile of this microorganism against antimicrobials routinely used in veterinary therapy. The antimicrobial profile of Eugenia uniflora against E. coli clinical isolates was also analyzed. Specimens from the recto-anal junction mucosa were investigated by using chromogenic medium and identification of E. coli was done using microbiological methods (Gram staining, indole test, methyl red test, Voges-Proskauer test, citrate test, urease test, and hydrogen sulfide test). The stx1 and stx2 genes corresponding to the STEC pathotype were evaluated by using polymerase chain reaction and electrophoresis. The susceptibility profile to antimicrobial agents commonly used in veterinary therapeutic practice and the antimicrobial effect of lyophilized hydroalcoholic extract of E. uniflora L. leaves against E. coli clinical isolates were evaluated by disk diffusion and microdilution methods. Shiga toxin-positive E. coli was identified in 45% of diarrheic newborn calves (stx1 = 23.2%, stx2 = 4.0%, stx1 + stx2 = 18.2%). The frequency of stx-positive E. coli in the bacterial population was equal to 17.0% (168/990 clinical isolates): 97 (9.8%) stx1-positive E. coli, 12 (1.2%) stx2-positive E. coli, and 59 (6.0%) stx1 + stx2-positive E. coli isolates. All stx-positive E. coli analyzed showed resistance to multiple drugs, that is, from 4 to 10 antimicrobials per clinical isolate (streptomycin, tetracycline, cephalothin, ampicillin, sulfamethoxazole + trimethoprim, nitrofurantoin and nalidixic acid, ciprofloxacin, gentamicin, and chloramphenicol). Effective management measures should be implemented, including clinical and laboratory monitoring, in order to promote animal and worker health and welfare, prevent and control the spread of diseases, and ensure effective treatment of infectious diseases. The E. uniflora L. leaves showed inhibition of microbial growth based on the diameter of halos, ranging from 7.9 to 8.0 mm and 9.9 to 10.1 mm for concentrations of 50 and 150 mg/mL, respectively. This plant displayed bacteriostatic action and a minimum inhibitory concentration of 12.5 mg/mL for all clinical isolates. Its clinical or synergistic effects with antimicrobial agents must be determined from clinical and preclinical trials. 相似文献
564.
Juliana de Carvalho Delgado Thais Rose dos Santos Hamilton Camilla Mota Mendes Adriano Felipe Perez Siqueira Marcelo Demarchi Goissis José Buratini Mayra Elena Ortiz D’Ávila Assumpção 《Reproduction in domestic animals》2021,56(5):754-763
In vitro embryo production (IVP) efficiency is reduced when compared to in vivo. The basic knowledge of bovine in vitro oocyte maturation (IVM) mechanisms provides support to improve in vitro embryo production yields. The present study assessed the effects of bone morphogenetic protein 15 (BMP15), fibroblast growth factor 16 (FGF16) and their combined action on cumulus cells (CC) expansion, oocyte and CC DNA fragmentation, oocyte nuclear maturation, energetic metabolism and progesterone production in bovine IVM. Cumulus-oocyte complexes (COC) were matured in control or supplemented media containing BMP15 (100 ng/ml), FGF16 (10 ng/ml) or BMP15 combined with FGF16; and assessed at 0 and 22 hr of IVM. BMP15 alone or its association with FGF16 enhanced cumulus expansion. BMP15 decreased DNA fragmentation in both CC and oocytes, and improved oocyte nuclear maturation rate. In addition, BMP15 increased CC progesterone production, an effect not previously reported. The present study reinforces previous data pointing to a beneficial influence of BMP15 during IVM, while providing novel evidence that the underlying mechanisms involve increased progesterone production. 相似文献
565.
Sebastin Muoz‐Leal lvaro A. Faccini‐Martínez Jairo Prez‐Torres Sandra M. Chala‐Quintero Maria T. Herrera‐Sepúlveda Claudia Cuervo Marcelo B. Labruna 《Zoonoses and public health》2021,68(1):12-18
Bats have been implicated as reservoirs of relapsing fever group spirochaetes since the beginning of the last century. Recently, bat‐associated spirochaetes have been reported as human pathogens. In 1968, a spirochaete was detected in blood of the bat Natalus tumidirostris captured inside the Macaregua cave, Colombia. Data on this microorganism were never published again. The aim of this study was to evaluate the presence of Borrelia DNA in blood from bats of Macaregua cave. We performed molecular analyses using a genus‐specific real‐time PCR targeting the 16S rRNA to detect DNA of Borrelia in blood samples from 46 bats captured in the Macaregua cave. Positive samples were submitted to a battery of PCRs aiming to amply Borrelia 16S rRNA, flaB, glpQ, p66, ospC, clpA, clpX, nifS, pepX, pyrG, recG, rplB and uvrA genes. Seventeen samples were positive for Borrelia after real‐time PCR. With the exception of flaB gene, attempts to amplify further loci were unsuccessful. Nucleotide and amino acid divergences of four flaB haplotypes characterized from blood of Carollia perspicillata showed Borrelia burgdorferi sensu lato (Bbsl) as the most closely related group. A phylogenetic tree including 74 sequences of the genus confirmed this trend, since Borrelia genotypes detected in bats from Macaregua formed a monophyletic group basally positioned to Bbsl. Our results suggest that Borrelia genotypes characterized from bats roosting in the Macaregua cave might constitute a new taxon within the genus. This is the first molecular characterization of a Borrelia sp. in Colombia. 相似文献
566.
Juan Hirzel Pablo Undurraga Lorenzo León Marcelo Panichini Jorge Carrasco Jorge González 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(4):285-293
ABSTRACTThe incorporation of previous crop residues in agricultural management benefits soil fertility, crop production, and environment. However, there is no enough information about maximum residue application level without negative effect over next crop yield. To evaluate maize (Zea mays L.) yield under short-time conservation management with incorporation and/or importation of different residue levels, a biannual rotation experiment was conducted in ash volcanic soil in south-central Chile. The experiment consisted of two previous crops, canola (Brassica napus L.) and bean (Phaseolus vulgaris L.), and four levels of residue incorporation (0%, 50%, 100%, and 200% of generated residue; from 0 to 21.4?Mg?ha?1 for canola and from 0 to 19.0?Mg?ha?1 for bean). Previous crop species and residue level affected some nutrients concentrations in grain and plant and some soil chemical properties, without effect in maize yield, which averaged 16.6?Mg?ha?1. Bean residue increased Ca and reduced S in maize plant, increasing soil P, Ca, Mg and K (P?<?0.05). Maize grain Ca content was positively and proportionally affected by canola residue level and negatively and proportionally affected by bean residue level. All canola residue levels increased soil pH and Mg, but the highest level reduced soil S; soil P concentration increased proportionally with bean residue level. The highest bean residue level increased soil S. Different crop and levels of residue did not affect maize yield but did some plant nutrient concentration, and also affected some soil chemical properties. 相似文献
567.
568.
569.
Heisler LK Cowley MA Tecott LH Fan W Low MJ Smart JL Rubinstein M Tatro JB Marcus JN Holstege H Lee CE Cone RD Elmquist JK 《Science (New York, N.Y.)》2002,297(5581):609-611
D-fenfluramine (d-FEN) was once widely prescribed and was among the most effective weight loss drugs, but was withdrawn from clinical use because of reports of cardiac complications in a subset of patients. Discerning the neurobiology underlying the anorexic action of d-FEN may facilitate the development of new drugs to prevent and treat obesity. Through a combination of functional neuroanatomy, feeding, and electrophysiology studies in rodents, we show that d-FEN-induced anorexia requires activation of central nervous system melanocortin pathways. These results provide a mechanistic explanation of d-FEN's anorexic actions and indicate that drugs targeting these downstream melanocortin pathways may prove to be effective and more selective anti-obesity treatments. 相似文献
570.
Lira NS Montes RC Tavares JF da Silva MS da Cunha EV de Athayde-Filho PF Rodrigues LC da Silva Dias C Barbosa-Filho JM 《Marine drugs》2011,9(11):2316-2368
Aplysina is the best representative genus of the family Aplysinidae. Halogenated substances are its main class of metabolites. These substances contribute greatly to the chemotaxonomy and characterization of the sponges belonging to this genus. Due to their pharmacological activities, these alkaloids are of special interest. The chemistry of halogenated substances and of the alkaloids has long been extensively studied in terrestrial organisms, while the number of marine organisms studied has just started to increase in the last decades. This review describes 101 halogenated substances from 14 species of Aplysina from different parts of the world. These substances can be divided into the following classes: bromotyramines (A), cavernicolins (B), hydroverongiaquinols (C), bromotyrosineketals (D), bromotyrosine lactone derivatives (E), oxazolidones (F), spiroisoxazolines (G), verongiabenzenoids (H), verongiaquinols (I), and dibromocyclohexadienes (J). A compilation of their (13)C NMR data is also part of the review. For this purpose 138 references were consulted. 相似文献