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41.
The present work aimed to investigate the presence of T. vivax DNA in the semen of experimentally infected goats. Twelve male goats native to the Brazilian Northeast, adults, were randomly assigned to two experimental groups: the infected group consisting of six goats infected intravenously with 0.5 mL of blood containing approximately 1.25?×?105 trypomastigotes of T. vivax, and a control group composed of six uninfected goats. After the infection, clinical examinations aiming to evaluate rectal temperature, parasitemia and hematocrit were performed. Semen samples were collected from goats by electroejaculation on the 7th, 14th and 21st days post-infection (dpi). The recombinant DNA-encoding gene encoding the L-like-specific gene for T. vivax. The infection was characterized by increased rectal temperature, high parasitemia and significant reduction of hematocrit values. Results for T. vivax DNA detection using TviCatL-PCR were positive in all semen samples from the infected group collected on 7th, 14th and 21st dpi. The presence of T. vivax DNA in 7th dpi suggests the early invasion of the parasite in the reproductive organs. Also, the finding of T. vivax DNA in all periods analyzed may suggest the continued elimination of the parasite in the semen, which may increase the chances of sexual transmission. Thus, T. vivax DNA is recorded for the first time in the semen of infected goats. Thus, these data are of great importance, since the detection of the T. vivax genetic material in the semen may point to the possibility that the parasite may be transmitted through the sexual pathway.  相似文献   
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This study aimed to evaluate the effects of forage neutral detergent fiber (fNDF) levels on the voluntary feed intake, digestibility, ruminal fermentation and feeding behavior of goats fed diets with cactus pear. Five non‐lactating ruminally cannulated goats fed ad libitum were randomly assigned to a 5 × 5 Latin square design. Treatments consisted of levels of fNDF at 0, 109, 222, 339 and 463 g/kg of dry matter (DM) in cactus pear‐based diets. The intakes of DM and NDF were quadratically affected (p ≦ .045) by fNDF levels. Voluntary water intake (VWI) increased linearly as the fNDF levels increased in the diet. The digestibility coefficients of organic matter, NDF and ether extract and total digestible nutrients concentration were quadratically affected (p ≦ .048) by fNDF levels. The ruminal pH linearly increased (p = .001) with fNDF levels, ranging from 5.44 to 5.81 for diets containing 0 and 463 g fNDF/kg DM, respectively. The fNDF levels promoted a linear increase (p = .006) in chewing time, linearly decreased (p = .007) resting time and quadratically affected (p = .033) rumination time. The inclusion of fNDF in the diets provided favorable conditions for ruminal function, digestibility and feeding behavior in goats fed diets containing cactus pear.  相似文献   
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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   
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A pig was in left lateral recumbency with limb spasticity, accentuated prostration, and strabismus, and was euthanized. During autopsy, yellowing of the leptomeninges at the ventral pons to medulla oblongata was noted. In the cerebellar peduncles, there was a focally extensive black-to-yellow area at the level of the vestibular nuclei. Histologic examination revealed a cross-section of a nematode larva, consistent with Stephanurus dentatus, bordered by edema and marked infiltration of mononuclear cells, plasma cells, and a few eosinophils. Vacuolation of the neuropil, with rare gitter cells and axonal spheroids, was also observed. We diagnosed parasitic encephalitis caused by S. dentatus migration based on the pathology findings and characterization of the parasite.  相似文献   
45.
Some fish species have a limited ability to metabolize dietary carbohydrates. An important tool for understanding carbohydrate metabolism is the application of the glucose tolerance test, which can be performed orally or intraperitoneally. To evaluate carbohydrate tolerance in the fruit‐eating fish pacu, two experiments were performed, one with oral administration by gavage of three carbohydrate types (glucose, fructose and starch, 2.0 g/kg body weight (BW)) and the other with intraperitoneal injection (IP) of glucose (500 mg/kg BW). Oral glucose resulted in an increase in plasma glucose 2 hr later with the peak at 4 hr (8.30 mmol/L), and return to baseline between 6 and 12 hr; starch administration promoted a peak after 4 hr (7.70 mmol/L), returning to the baseline at 6 hr. The administration of fructose promoted a moderate peak after 2 hr (5.71 mmol/L), and return to baseline for the time points that followed. Elevated serum cholesterol levels were observed 2 and 24 hr after administration of glucose and starch. Hepatic glycogen levels increased within 24 hr, regardless of the type of carbohydrate administered. IP glucose load resulted in a peak of plasma glucose 3 hr post injection (6.91 mmol/L), returning to baseline 6 hr later. There was a reduction in the concentration of triglycerides at 24 hr. The results demonstrate that pacu metabolize both oral (glucose or starch) and intraperitoneal (glucose) carbohydrate loads after 6 hr, suggesting good ability to deal with dietary carbohydrates.  相似文献   
46.
Lunasin and Bowman-Birk protease inhibitor (BBI) are two soybean peptides to which health-promoting properties have been attributed. Concentrations of these peptides were determined in skim fractions produced by enzyme-assisted aqueous extraction processing (EAEP) of extruded full-fat soybean flakes (an alternative to extracting oil from soybeans with hexane) and compared with similar extracts from hexane-defatted soybean meal. Oil and protein were extracted by using countercurrent two-stage EAEP of soybeans at 1:6 solids-to-liquid ratio, 50 °C, pH 9.0, and 120 rpm for 1 h. Protein-rich skim fractions were produced from extruded full-fat soybean flakes using different enzyme strategies in EAEP: 0.5% protease (wt/g extruded flakes) used in both extraction stages; 0.5% protease used only in the second extraction stage; no enzyme used in either extraction stage. Countercurrent two-stage protein extraction of air-desolventized, hexane-defatted soybean flakes was used as a control. Protein extraction yields increased from 66% to 89-96% when using countercurrent two-stage EAEP with extruded full-fat flakes compared to 85% when using countercurrent two-stage protein extraction of air-desolventized, hexane-defatted soybean flakes. Extruding full-fat soybean flakes reduced BBI activity. Enzymatic hydrolysis reduced BBI contents of EAEP skims. Lunasin, however, was more resistant to both enzymatic hydrolysis and heat denaturation. Although using enzymes in both EAEP extraction stages yielded the highest protein and oil extractions, reducing enzyme use to only the second stage preserved much of the BBI and Lunasin.  相似文献   
47.
In this study, we tested the capability of enterobacterial repetitive intergenic consensus (ERIC) and repetitive extragenic palindromic (REP) polymerase chain reaction (PCR) to detect genetic diversity among Escherichia coli strains isolated from chickens bearing clinical signs of colibacillosis and compared the genotypes so obtained with the O:H serotypes and virulence of those strains. The DNAs from 50 avian E. coli strains and from E. coli ATCC 25922 were used to amplify ERIC and REP sequences. DNA from avian strains produced from 8 to 17 bands by ERIC-PCR and from 6 to 20 bands by REP-PCR; E. coli ATCC produced 11 bands by both methods. ERIC and REP-PCR showed good discriminating power, and the dendograms based on the different patterns revealed extensive genetic diversity among the avian strains. Those strains were allocated into four major clonal clusters, each one with 60% of similarity by ERIC and REP-PCR, and those clusters corresponded to strains with different degrees of pathogenicity. However, 56% of the pathogenic strains (28/50) belonged to two out of three major clonal clusters, and 86% of the nonpathogenic strains tended to group in one cluster and one subgroup. The 32 serotypes detected were distributed in all clusters, and within a serogroup, different DNA fingerprints were observed; however, strains with same serotypes tended to form clusters with similarity coefficients greater than 80%. These results suggest that no specific serotype and genotype is responsible for colibacillosis and that REP and ERIC-PCR are reproducible techniques that can improve the studies needed to clarify the pathways to the pathogenesis of colibacillosis.  相似文献   
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The present study was conducted to decipher the proteome of in vivo-produced pre-implantation ovine embryos. Ten locally adapted Morana Nova ewes received hormonal treatment and were inseminated 12 hr after ovulation. Six days later, 54 embryos (morula and blastocyst developmental state) were recovered from eight ewes and pooled to obtain sufficient protein for proteomic analysis. Extracted embryo proteins were analysed by LC-MS/MS, followed by identification based on four database searches (PEAKS, Proteome Discoverer software, SearchGUI software, PepExplorer). Identified proteins were analysed for gene ontology terms, protein clusters and interactions. Genes associated with the ovine embryo proteome were screened for miRNA targets using data sets of TargetScan ( http://www.targetscan.org ) and mIRBase ( http://www.mirbase.org ) servers. There were 667 proteins identified in the ovine embryos. Biological processes of such proteins were mainly related to cellular process and regulation, and molecular functions, to binding and catalytic activity. Analysis of the embryo proteins revealed 49 enriched functional clusters, linked to energy metabolism (TCA cycle, pyruvate and glycolysis metabolism), zona pellucida (ZP), MAPK signalling pathway, tight junction, binding of sperm to ZP, translation, proteasome, cell cycle and calcium/phospholipid binding. Sixteen miRNAs were related to 25 pre-implantation ovine embryo genes, all conserved in human, bovine and ovine species. The interaction network generated by miRNet showed four key miRNAs (hsa-mir-106b-5p; hsa-mir-30-5p; hsa-mir-103a-5p and hsa-mir-106a-5p) with potential interactions with embryo-expressed genes. Functional analysis of the network indicated that miRNAs modulate genes related to cell cycle, regulation of stem cell and embryonic cell differentiation, among others. Retrieved miRNAs also modulate the expression of genes involved in cell signalling pathways, such as MAPK, Wnt, TGF-beta, p53 and Toll-like receptor. The current study describes the first major proteomic profile of 6-day-old ovine embryos produced in vivo, setting a comprehensive foundation for our understanding of embryo physiology in the ovine species.  相似文献   
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