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151.
Pimentel Dde S Ramos CA Ramos RA de Araújo FR Borba ML Faustino MA Alves LC 《Veterinary parasitology》2012,185(2-4):286-289
This paper describes an outbreak of Trypanosoma vivax for the first time in the state of Pernambuco, Brazil, affecting dairy cattle in the municipality of Itambé in the northern coastal zone of the state. Clinical signs compatible with infection by blood protozoa and epidemic miscarriages were observed. The diagnosis of T. vivax was confirmed through biometric microscopy and molecular analysis with PCR and DNA sequencing. The T. vivax isolate detected in the present study proved to be genetically very close to other Brazilian isolates of the protozoan despite being geographically distant. 相似文献
152.
Portes Jde A Netto CD da Silva AJ Costa PR DaMatta RA dos Santos TA De Souza W Seabra SH 《Veterinary parasitology》2012,186(3-4):261-269
Toxoplasma gondii, the agent of Toxoplasmosis, is an obligate intracellular protozoan able to infect a wide range of vertebrate cells, including nonprofessional and professional phagocytes. Therefore, drugs must have intracellular activities in order to control this parasite. The most common therapy for Toxoplasmosis is the combination of sulfadiazine and pyrimethamine. This treatment is associated with adverse reactions, thus, the development of new drugs is necessary. In previous studies, naphthoquinone derivatives showed anti-cancer activity functioning as agents capable of acting on groups of DNA, preventing cancer cells duplication. These derivatives also display anti-parasitic activity against Plasmodium falciparum and Leishmania amazonensis. The derivative pterocarpanquinone tested in this work resulted from the molecular hybridization between pterocarpans and naphtoquinone that presents anti-tumoral and anti-parasitic activities of lapachol. The aim of this work was to determine if this derivative is able to change T. gondii growth within LLC-MK2 cells. The drug did not arrest host cell growth, but was able to decrease the infection index of T. gondii with an IC(50) of 2.5 μM. Scanning and transmission electron microscopy analysis showed morphological changes of parasites including membrane damage. The parasite that survived tended to encyst as seen by Dolichos biflorus lectin staining and Bag-1 expression. These results suggest that pterocarpanquinones are drugs potentially important for the killing and encystment of T. gondii. 相似文献
153.
Fabio Ribeiro Braga Jackson Victor Araújo Andr Ricardo Silva Juliana Milani Araujo Rogrio Oliva Carvalho Alexandre Oliveira Tavela Artur Kanadani Campos Giovanni Ribeiro Carvalho 《Veterinary parasitology》2009,163(4):335-340
The viability of a fungal formulation using the nematode-trapping fungus Duddingtonia flagrans was assessed for the biological control of horse cyathostomin. Two groups (fungus-treated and control without fungus treatment), consisting of eight crossbred mares (3–18 years of age) were fed on Cynodon sp. pasture naturally infected with equine cyathostome larvae. Each animal of the treated group received oral doses of sodium alginate mycelial pellets (1 g/(10 kg live weight week)), during 6 months. Significant reduction (p < 0.01) in the number of eggs per gram of feces and coprocultures was found for animals of the fungus-treated group compared with the control group. There was difference (p < 0.01) of 78.5% reduction in herbage samples collected up to (0–20 cm) between the fungus-treated group and the control group, during the experimental period (May–October). Difference of 82.5% (p < 0.01) was found between the fungus-treated group and the control group in the sampling distance (20–40 cm) from fecal pats. During the last 3 months of the experimental period (August, September and October), fungus-treated mares had significant weight gain (p < 0.01) compared with the control group, an increment of 38 kg. The treatment with sodium alginate pellets containing the nematode-trapping fungus D. flagrans reduced cyathostomin in tropical southeastern Brazil and could be an effective tool for biological control of this parasitic nematode in horses. 相似文献
154.
Leandro Maia MV MS Maria Vernica de Souza MV MS DS Pharmacist-Biochemical Jos Ivo Ribeiro Júnior BS MS DS Acio Carlos de Oliveira Geraldo Eleno Silveira Alves MV MS DS Larcio dos Anjos Benjamin MV MS DS Yamê Fabres Robaina Sancler Silva Bruna Mota Zandim MV Jos do Carmo Lopes Moreira MD MS 《Journal of Equine Veterinary Science》2009,29(8):618-626
This study was carried out to evaluate the effect of platelet-rich plasma (PRP) on the treatment of tendinopathy induced in the superficial digital flexor tendon (TFDS) of horses, by using histologic evaluation. Six healthy crossbred geldings aged 8 to 15 years (12 ± 3) were used. The TFDS tendinopathy was provoked in both forelimbs, by intratendinous administration of 2.5 mg collagenase (2.5 mg/mL), and this procedure was considered as the beginning of the experimental phase. At 12 days after induction of the tendinopathy, the animals were subjected to the following treatments: (1) in the lesion caused in the right superficial digital flexor tendon (PRP-treated group), 2.5 mL PRP activated with calcium chloride at 0.0125 mol/L at concentrations from 320,000 to 500,000 platelets/μL, were injected; (2) in the tendinopathy of the left SDFT (control group), 2.5 mL 0.9% saline solution was administrated. Thirty-six days after the treatments, a biopsy of the injured area was performed for histologic evaluation. In both groups, the histologic analysis showed an increase in the fibroblastic density, as well as the presence of neovascularization, lymphocytes, and plasmocytes infiltrate and tissue organization at variable intensity. In the PRP-treated group, the SDFT was more organized, with the collagen fibers and fibroblasts being better arranged on the tendon matrix. The numbers of the fibroblasts and blood vessels did not differ between the groups. Histologic evaluation 36 days after tendinopathy showed that injuries under a single PRP treatment present a more uniform and organized tissue repair when compared with the control group. 相似文献
155.
Siqueira AK Ribeiro MG Leite Dda S Tiba MR Moura Cd Lopes MD Prestes NC Salerno T Silva AV 《Research in veterinary science》2009,86(2):206-210
The aim of this study was to compare the prevalence of virulence genes in 158 Escherichia coli strains isolated from 51 clinical cases of UTIs, 52 of pyometra and from 55 fecal samples from healthy dogs by PCR. papC was found in 12 (23.5%) strains isolated from UTIs, 19 (36.5%) from pyometra and 10 (18.2%) from feces. papGII was observed in 3 (5.8%) strains from pyometra, and papGIII in 10 (19.6%) from UTIs, 15 (28.8%) from pyometra and 9 (16.4%) from feces. sfaS was detected in 22 (43.1%) strains from UTIs, 24 (46.1%) from pyometra and 19 (34.5%) from feces. hlyA was observed in 17 (33.3%) strains from UTIs, 18 (34.6%) from pyometra and 7 (12.7%) from feces, while cnf-1 was detected in 11 (21.6%) from UTIs, 21 (40.4%) from pyometra and 9 (16.4%) from feces. iucD was observed in 12 (23.5%) strains from UTIs, 9 (17.3%) from pyometra and 1 (1.8%) from feces. usp was found 17 (33.3%) isolates from UTIs and 36 (69.9%) from pyometra. 相似文献
156.
Mrcio Garcia Ribeiro Marconi Rodrigues de Farias Uwe Roesler Katja Roth Sabrina Mari Rodigheri Marco Antonio Ostrowsky Tatiana Salerno Amanda Keller Siqueira Marta Catarina Fernandes 《Research in veterinary science》2009,87(3):479-481
This is a case report of enteric protothecosis caused by Prototheca zopfii in an eight-year-old male mixed breed dog with a history of chronic bloody diarrhea, loss of appetite and weight loss. Algae were isolated from rectal scrapings in defibrinated sheep blood agar and dextrose Sabouraud agar. Cytological evaluation showed the presence of globular and cylindrical organisms with a defined capsule and variable number of endospores, characteristic of the genus Prototheca, in the rectum of the animal. Scanning electron microscopy of P. zopfii strains at different development stages confirmed the diagnosis of algal infection. Molecular identification using a conserved 18S rDNA gene sequence determined that the strain belonged to genotype 2. This report describes success on treatment of canine protothecosis, diagnosed based on clinical, cytological, microbiological, scanning electron microscopy and genotypical findings. 相似文献
157.
Henrique M. Ribeiro David Fangueiro Fátima Alves Ernesto Vasconcelos João Coutinho Roland Bol Fernanda Cabral 《植物养料与土壤学杂志》2010,173(1):39-45
The dynamics of C mineralization in an organically managed Cambic Arenosol amended with hen manure, a stabilized compost (compost), and three different combinations of both fertilizers (varying from a 1:100 to a 1:10 ratio) were studied during an incubation experiment to estimate the potential of such combinations to preserve/restore soil C content relative to single applications. A strong increase of the CO2‐C emissions relative to the unamended soil (control) was observed after soil application of all five organic‐fertilizer treatments. A significantly higher amount of applied C was lost in hen‐manure treatment (648 mg CO2‐C [g C applied]–1) when compared to compost (159 mg CO2‐C [g C applied]–1) or to the three combined treatments (176–195 mg CO2‐C [g C applied]–1). The first‐order exponential model and the double exponential model were used to fit the C‐mineralization data in the treatments considered. Results showed that mixing “small” amounts of hen manure with compost did not affect the total amount of potentially mineralizable C, but significantly increased the mineralization rate constant. Clearly, combinations of both fertilizers promoted an initial faster mineralization of the organic matter, and consequently a faster release of nutrients, without affecting the total amount of C sequestered in soil. 相似文献
158.
Moraes ML Ribeiro AM Kessler AM Ledur VS Fischer MM Bockor L Cibulski SP Gava D 《Journal of animal science》2012,90(8):2590-2598
An experiment was conducted to evaluate the effect of CLA on the immune response and performance of piglets when subjected to an immune challenge. A total of 32 weanling pigs (17 to 23 d of age) with an initial BW of 8.9 kg were allotted to a 3 × 2 factorial arrangement of treatments. There were 3 levels of dietary CLA (0%, 1%, and 2%) and 2 levels of lipopolysaccharide (LPS) challenge (unchallenged and challenged). Challenged pigs were challenged on d 7 and 21. On d 4 and 18, all pigs were inoculated with BSA for assessment of IgG production. There was no difference in growth performance among piglets receiving different CLA supplementation levels. However, LPS-challenged piglets had poorer BW (P < 0.05), ADFI (P < 0.01), and ADG (P < 0.001) compared with the control group at d 35 postweaning. Lipopolysaccharide-challenged piglets also had increased respiratory rate (P < 0.001) and rectal temperature (P < 0.001), and decreased plasma proteins, hematocrit, and white blood cell counts (P < 0.05). Production of IgG against BSA was increased in the 1% CLA supplementation group (P < 0.001), indicating that CLA has an immunomodulatory effect. Supplementation with CLA did not affect lymphocyte proliferation, percentage of CD4(+) and CD8(+) cells, plasma proteins, red and white blood cell count, respiratory rate, or rectal temperature after LPS challenge. Although CLA supplementation did not influence growth performance or certain immune system measurements, the increased IgG titers with 1% CLA dietary supplementation indicate that it has a beneficial effect on the humoral immune system of weaned piglets. 相似文献
159.
Evaluation of Soy Protein Concentrate and Meat and Bone Meal as a Replacement for Fish Meal in the Diet of Nile Tilapia Fingerlings 下载免费PDF全文
Manoel Joaquim Peres Ribeiro Rose M. Vidotti Leandro A. Ferreira Giovani Sampaio Gonçalves 《Journal of the World Aquaculture Society》2016,47(3):369-375
This experiment evaluated soy protein concentrate (SPC) and meat and bone meal as a replacement for fish meal protein (FP) in the diet of Nile tilapia fingerlings. Five diets were evaluated including a control diet (50.0% crude protein [CP], of which half the protein came from fish meal [FM]), and four diets in which FM was replaced by increasing amounts of SPC (25.5, 50.0, 75.5, and 100.0%) in combination with meat and bone meal. At the conclusion of a 60‐d growth trial, the following parameters were determined: final weight (FW), final length (FL), weight gain (WG), feed intake (FI), apparent feed conversion (AFC), survival (SUR), and production cost. The estimate of the best replacement value was determined by polynomial regression and the linear response plateau. The results showed significant (P < 0.05) improvement for WG and AFC ratio as FM was gradually replaced by SPC. The parameters FL and FI reached their optimum value at a replacement level of 100% SPC. These results show that it is feasible to use a combination of SPC and meat and bone meal in a balanced feed formulation as an alternative protein source in the diets of Nile tilapia fingerlings. 相似文献
160.
The diagnosis of acute babesiosis by direct examination of blood smears has some limitations and the indirect serological methods currently in use are designed for detection of IgG, which may not be detectable at an early stage of infection. There is a need, therefore, for rapid and reliable procedures to diagnose acute infections. An ELISA system using a crude antigenic preparation of Babesia bovis was standardized for the detection of IgM antibodies. Optimal dilutions of the antigen, using positive and negative reference sera, were determined by checkerboard titrations. Serum samples of cattle imported from tick-free areas collected before and during an immunization process were used to validate the tests. The specificity was 94% and sensitivity 100%. Specific IgM antibodies against B. bovis first appeared on the 11th day post-inoculation (p.i.) in animals infested with Boophilus microplus ticks and on the 19th day p.i. in animals which had been inoculated with infected blood. Antibody titers decreased after Day 33; however, all animals remained positive until the end of the experiment (124 days). 相似文献