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101.
Panagrellus redivivus is a nematode with a high protein content and low‐cost production. It is successfully used in the larviculture of shrimp, however, it has not yet been evaluated as feed for Betta splendens larvae. Thus, the objective of this study was to evaluate P. redivivus as feed for betta larvae maintained at different depths of water. The experiment was based on a completely randomized 3 × 2 factorial design, represented by two feed types and one alternating feeding regime plus two water depths (2.5 and 5.0 cm). The Artemia feed promoted the highest weight gain, followed by the alternating feeding regime. The single use of the nematode as live feed produced the poorest weight gain. The water depth and the feeding method influenced the specific growth rate (SGR). At a depth of 2.5 cm, the alternating feeding promoted similar SGR compared to fish fed with Artemia only. Furthermore, at the greater water depth an improvement in SGR was observed in fish fed Artemia only, but the similarity to alternating feeding regime remains. Thus, the inclusion of nematode is an appropriate and lower cost feed strategy for the betta larviculture independent of water depths.  相似文献   
102.

Objective

To evaluate the use of an experimental colloid model for teaching veterinary anesthesia residents ultrasound-guided technique for nerve blockade.

Study design

Prospective, blinded and randomized.

Methods

Colloid models were constructed for practice in ultrasound-guided needle location. Nine veterinary anesthesia residents with no prior experience of ultrasound-guided technique for nerve blocks were randomly divided into three groups. Each group received theoretical orientation. Two groups were assigned to practical training using the experimental model: group 1 (G1) received 2 hours of training and group 2 (G2) received 1 hour of training prior to testing with specific tasks. Group 3 (G3) received no practical training. During testing, the time required for task completion (e.g., display of structures and positioning a needle) and the number of failures were recorded.

Results

The average times to completion of the tasks and the number of technical failures were: G1, 47 seconds and 1 failure; G2, 68 seconds and 2 failures; G3, 187 seconds and 7 failures.

Conclusions and clinical relevance

In residents with no prior experience of ultrasound-guided needle placement, using an experimental colloid model and a longer training period was associated with increased accuracy and decreased time to task completion. Based on the results of this study, training with an experimental model can be recommended to improve the speed and accuracy of needle manipulation using ultrasound in clinicians with no prior experience of ultrasound-guided technique.  相似文献   
103.
The soil areas affected by salts have increased in recent years. Searching intensively for management and recovery strategies should help minimize these problems. Studies related to the response of halophytes to fertilization can provide important information regarding the most adequate management for phytoremediation. The aim of this study was to evaluate dry matter production and sodium extraction capacity of atriplex plants, in response to nitrogen doses, with and without phosphorus application. The experiment was carried out in a greenhouse at the Federal Rural University of Pernambuco (UFRPE), in Recife, Pernambuco, Brazil and was set up in a randomized block design, with four replicates, in a 2 × 5 factorial scheme (0 and 134 mg dm?3 of P and 0, 20, 40, 60, and 80 mg dm?3 of N). The addition of nitrogen (N) and improved sodium (Na) uptake increased Na contents by 4.1, 3.6, and 1.8 times, for P0, and by 4.0, 8.4, and 2.1, for P134, in leaves, stems, and roots, respectively. There was a decrease in Na both in the saturation-paste extract and in the exchange complex with the increase in N in soil. N supply potentiates Na extraction by Atriplex nummularia, being a feasible technique to recover saline soils through phytoremediation.  相似文献   
104.
This case study reported the presence of short tail sperm defect in the semen of three Nelore breed bulls. The sperm presented 0% of motility in the three animals evaluated and a total of 70%, 61% and 34% of pathologies of the intermediate piece of the tail respectively for animals 1, 2 and 3. It was identified that animals 2 and 3 had high degree of inbreeding, although no relationship was found with animal 1. Animal 2 was the only one that presented inbreeding coefficient (6.25%). His half‐sib (animal 3) and animal 1, from the same herd, had shown no inbreeding, showing that inheritance is not the only determinant factor for its incidence on Nelore males.  相似文献   
105.
Background: The efficacy of intravenous (IV) administration of azumolene (Az), an analogue 30‐fold more soluble than dantrolene, on pigs susceptible to malignant hyperthermia (MH) is incompletely understood. Objective: To evaluate efficacy of Az on MH crisis in pigs. Animals: Eight normal (MHN) and 7 susceptible to MH (MHS) pigs (Landrace × Large White × Pietran). Methods: Prospective, laboratory trial. Hypermetabolic crisis was observed in MHS pigs, but not in MHN pigs, after a combined administration of inhaled halothane (1.5%) and IV injection of succinylcholine (SCh; 2.5 mg/kg). Susceptibility was confirmed using a caffeine and halothane contracture test. Az was administered 15 minutes after administration of SCh. Results: Respiratory acidosis (pH 7.16 ± 0.02; Pco 2, 46.2 ± 9.1 mmHg, HCO3, 22.5 ± 2.3 mmol/L), fever (38.2 ± 1.1°C), cardiac arrhythmias, and muscle contracture were observed in MHS pigs. MHS pigs (n = 5) treated with Az (2 mg/kg IV) survived the crisis with attenuation of signs (pH 7.30 ± 0.10; Pco 2, 36.3 ± 4.5 mmHg; HCO3, 22.9 ± 2.3 mmol/L) and recovery of normal muscle tone and cardiac rhythm. Conclusions and Clinical Importance: Az represents a possible substitute for dantrolene to reverse MH crisis in susceptible pigs.  相似文献   
106.
Study of Biodegradation Processes of BTEX-ethanol Mixture in Tropical Soil   总被引:1,自引:0,他引:1  
In Brazil, gasoline is currently blended with ethanol and both compounds may contaminate the environment when spills occur. Ethanol preferential biodegradation delays gasoline degradation in the aquifer, as previously observed; in unsaturated soil a delayed recovery of culturable bacteria and removal of residues in the presence of ethanol suggest a similar situation. This study monitors microbial degrading activity in unsaturated soil with BTEX and BTEX-ethanol mixtures under tropical conditions as well as the effects of bioventing on contaminants degradation. Enzymatic activity was quantified by measuring fluorescein-diacetate hydrolysis by microorganisms, which determines total degrading activity in soil. As microbial enhanced activity may alter soil electromagnetic properties, soil dielectric constant shifts were monitored using Time Domain Reflectometry (TDR), while chemical analyses evaluated contamination residues throughout the experiment. Results suggest that ethanol delays BTEX biodegradation and that bioventing may compensate for this delay by providing oxygen for the continuation of microbial activity. Contamination and bioventing stimulated soil microbiota, while culturable populations were inhibited by contamination, showing soil toxicity. The presence of ethanol caused a higher and longer-lasting boost in enzymatic activity; TDR measurements did not follow these activity shifts, proving not to be an adequate tool for evaluating microbial activity in these experimental conditions. Residual BTEX were detected only in ethanol-containing non-ventilated soils after contamination. The set of results suggests that ethanol could delay BTEX degradation because of its constitutive degradation by soil microbiota, but this effect may be bypassed by bioventing.  相似文献   
107.
Virulence factors of avian Escherichia coli   总被引:9,自引:0,他引:9  
A total of 45 strains of Escherichia coli isolates from chickens with colisepticemia were examined for virulence factors commonly found in pathogenic groups of E. coli. These strains were studied for the following: pathogenicity in 1-day-old chicks; toxin, hemolysin, and colicin production; cell invasiveness and adherence; hemagglutination for fimbriae detection; serum resistance; aerobactin production in iron-limited conditions; and plasmid content. The characteristics exhibited by virulent strains were invasion for HeLa and chicken fibroblast cells, serum resistance, colicin V, and aerobactin production. None of the isolates were toxigenic or positive in hemagglutination tests. The molecular genetic studies of the virulence factors by agarose electrophoresis showed that the plasmids of these strains are of high molecular weight.  相似文献   
108.
The biochemical profiles of crossbred dogs experimentally infected with the parasite Angiostrongylus vasorum were studied. Two groups of five dogs were experimentally inoculated with 50 and 100 third stage infective larvae (L3) of A. vasorum per kilogram of body weight. A third group of five uninfected animals were used as control. Serum from these animals were used for biochemical tests to measure total and fractioned proteins, urea, creatinine and to determine the activities of aspartate (AST), alanine (ALT) aminotransferase, gamma-glutamyl transferase (GGT), alkaline phosphatase (PAL) and creatine kinase isoenzyme MB (CK-MB). The alpha-1, alpha-2 and beta-globulins fractions showed alterations during acute phase of the infection. No modifications were observed in the biochemical profiles of ALT, AST, GGT, PAL, urea and creatinine. CK-MB was shown to be a good early indicator of cardiac injury in dogs experimentally infected with A. vasorum.  相似文献   
109.
110.
OBJECTIVE: To evaluate characteristics of a large epidemic of sporotrichosis in cats. DESIGN: Retrospective study. ANIMALS: 347 cats with naturally acquired infection with Sporothrix schenckii. PROCEDURE: Medical records were reviewed for data regarding clinical, mycologic, histopathologic, and routine hematologic and serum biochemical findings; assays for FIV-specific antibodies and FeLV antigen; antifungal treatment; and follow-up. RESULTS: Lesions varied from small papules to extensive zones of necrosis.Ten cats had no skin lesions, 114 had skin lesions at a single site, 86 had skin lesions in 2 sites, and 137 had skin lesions in 3 or more sites. Respiratory tract signs were observed in 154 cats and were the most frequent extracutaneous sign. Anemia, leukocytosis with neutrophilia, hypoalbuminemia, and hyperglobulinemia were the main blood abnormalities. Antibodies against FIV were detected in 28 cats, FeLV antigen was detected in 2 cats, and both were detected in 1 cat among 142 cats tested. During the study, 118 cats were lost to follow-up and 124 died. Of 266 cats that were treated, 68 were cured. Complete healing of the lesions was observed regardless of the presence of extracutaneous signs, general condition, treatment schedule, or coinfection with FIV. CONCLUSIONS AND CLINICAL RELEVANCE: Feline sporotrichosis was evident in subclinical to severe forms; however, cats can respond well to regular and prolonged antifungal treatment.  相似文献   
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