Combining eight research areas to foster the uptake of ecosystem‐based management in fresh waters

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Evaluation of hemato-immunological parameters during the reproductive cycle of the scallop Nodipecten nodosus in association with a carotenoid-enriched diet

The cultivation of scallops Nodipecten nodosus is a promising activity emerging in Brazil. The purpose of this study was to characterize the immune system of N. nodosus and evaluate the modulation of some hemato-immunological parameters during the reproductive cycle, in association with an astaxanthin-enriched diet. It was hypothesized that a supplementation on astaxanthin could enhance scallop immune system and minimize stress of reproduction. Scallops were separated in different groups: juveniles (J), adults (A), sexually mature (M), and recently spawned (S) animals. The last two groups were fed standard (M and S) or astaxanthin-enriched (Ma and Sa) diets. Scallop hemolymph contained two hemocyte populations: hyaline (HH) and granular hemocytes (GH). Antimicrobial peptides, similar to mussel defensins and mytilins, were found by immunodetection within the GH granules, even though the scallop hemolymph did not exhibit significant antimicrobial activity against different bacteria, including marine vibrios. Scallop hemocytes were able to phagocytose zymosan and produce reactive oxygen intermediates (ROI–NBT reduction). The number of circulating hemocytes (Neubauer chamber) varied from 12 to 26.10⁶ cells mL^− 1, and the GH was always the predominant cell type (67–99%). The plasma of N. nodosus contained lectins, specific to galactose and sialoconjugates, and their agglutinating activity was partially calcium-dependent. A phenoloxidase (PO) activity (146–446 U min^− 1 mg^− 1) was observed in the scallop hemolymph. However, this activity was not induced by trypsin or components of microorganism surface, and was strongly enhanced by alkaline pH (≥ 8.5). The total protein concentration of the plasma varied from 240 to 660 μg mL^− 1. In general terms, all examined hemato-immunological parameters (hemograms, superoxide anion production, PO activity, lectin titers and total protein concentration) had a similar profile during all the scallop reproductive cycle. Their levels increased significantly from juveniles to adults (except PO activity), and declined markedly (immune depletion) in the sexually mature scallops. After spawning, the animals had a tendency to recover the standard levels of their immune parameters. Apparently, the astaxanthin-enriched diet had no effect on the tested immune parameters except for a slight influence on the scallop immune-oxidative reactions (ROI production). The results obtained in this study suggested the occurrence of a general immune depletion in the sexually mature scallops, confirming that the reproductive stage is a critical period in scallop life.     

Effect of Marcela Extract (Achyroclines satureiodes) on the Shelf Life of Minced Tilapia (Oreochromis niloticus) Sausages

The effect of marcela extract (ME) on the shelf life of minced tilapia sausages was evaluated in this study. The level of phenolic compounds in the ME was 114.1 ± 2.9 mg GAE/g extract, and the DPPH free radical scavenging activity was 94.95 ± 1.34%. The ME protected the samples from color changes during storage. The addition of 0.5 and 0.75% ME significantly decreased lipid oxidation and microbial growth. The ME did not impact the sausages’ sensory quality, and the addition of 0.75% prevented sensory rejection during storage.     

小麦水分状况的光反射测量

反射测量可用于对作物的水分状况进行快速而经济的评估。该研究以土壤最大持水量为标准，设65%、52%、39%、32.5%、26%和19.5%共6个水处理水平。小麦叶片光反射的测量用数码相机进行，测量结果用L*a*b*颜色系统进行评估和分析。在该三维系统中，参数a*和b*分别描述绿/红和蓝/黄颜色的比例，参数L*用来描述颜色的浅淡。结果表明，随水胁迫加剧，小麦叶片光反射参数a*(绿/红)和/或b*(蓝/黄)在9个特定波段表现出有规律的增加，植株含水率与光反射参数b*之间呈线性负相关关系，其中与510～780 nm波段的光反射参数b*之间的决定系数r^{2最大，达到0.95。因此光反射测量可以作为小麦水分状况测量的一个重要工具。}     

Design,optimization, and application of a conventional PCR assay with an internal control for detection of ‘Candidatus Mycoplasma turicensis’ 16S rDNA in domestic cats from Brazil

Background: ‘Candidatus Mycoplasma turicensis’ (CMtc) is a hemotrophic bacterial species that can, alone or in combination, induce anemia in cats. The diagnostic test of choice for hemoplasma infections is PCR. Conventional PCR assays have been developed for the detection of Mycoplasma haemofelis (Mhf) and ‘Candidatus M. haemominutum’ (CMhm) but not for CMtc. Although real‐time PCR assays have been reported for all of the feline hemoplasmas, the expense of necessary instrumentation precludes its use in Brazil and many other countries. Objectives: The goals of this study were to develop and optimize a conventional PCR assay to diagnose CMtc using an internal control to detect false‐negative results, and to evaluate the occurrence of CMtc infection in domestic cats from Brazil. Methods: Species‐specific primers were designed and a PCR assay was developed for the detection of CMtc 16S rDNA in cat blood. Sensitivity was determined by serial 10‐fold dilutions of plasmid and DNA extracted from blood from an experimentally infected cat. EDTA blood samples from 373 cats were collected. DNA was extracted using a silica‐based protocol and tested using the PCR assay. Results: Primer concentration, annealing temperature, and MgCl₂ concentration were optimized in the presence and absence of the internal control. Two samples negative for the internal control were excluded. Of the remaining 371 samples (117 healthy and 254 unhealthy cats), 17 (4.6%) were positive for CMtc. Conclusion: These results demonstrate the utility of an optimized PCR assay to detect CMtc in feline blood samples. We also report for the first time the prevalence of CMtc infection in domestic cats in Brazil.     

Correlations entre le thymus et les hormones sexuelles chez le cobaye

Relations between thymus and sex hormones in Guinea Pigs Male and female Guinea Pigs were treated for different periods of time with sex hormones and gonadotropins. There were changes in the cytology and architecture of the thymic parenchyma. The most important conclusion was that folliculin has a strong involuting effect on the thymus and leads to the appearance of cells with Foà-Kurloff bodies. This effect is independent of hypophyseal stimulation. The obtained results underline the existence of close relations between thymus and gonads, and especially between the thymus and the estrogen secretion in the theca interna of the ovarian follicle.     

Congenital sensorineural deafness in dogs: a molecular genetic approach toward unravelling the responsible genes

Deafness is often diagnosed in different dog breeds and has been identified as a significant problem for breeders, owners and clinicians. The aetiology can be inherited or acquired, and a distinction must be made between sensorineural and conductive forms of deafness. This paper provides a brief overview of the varieties of findings in different dog breeds and in one breed in particular including prevalence, phenotypic and gender associations, histology, modes of inheritance and the number of contributing genes in congenital sensorineural deafness. We have also described molecular genetic approaches to canine hearing loss and discuss how comparative genomics could help reduce the prevalence of deafness in affected breeds leading to new insights into the molecular mechanisms of auditory function in both dogs and humans.     

A prospective study of postoperative surgical site infections in dogs and cats

OBJECTIVE: To assess postoperative surgical site infection (SSI) rate and to identify associated predictive factors. STUDY DESIGN: Prospective clinical study. ANIMALS: Dogs and cats that had surgery (1010 interventions) during 58 weeks from April 1999 to June 2000. METHODS: Data sheets were completed by clinicians. Patients were controlled for clinical evidence of SSI at suture removal. Two definitions of SSI ("infection" and "infection/inflammation") were developed specifically for this study and used for statistical analysis. Logistic regression models were built in order to identify significant predictive factors for SSI. RESULTS: Wounds with "infection/inflammation" occurred in 5.8% and "infected" wounds in 3% of patients. The outcome "infection" was associated with 3 major risk factors (duration of surgery, increasing number of persons in the operating room, dirty surgical site) and 1 protective factor (antimicrobial prophylaxis). The outcome "infection/inflammation" was associated with 6 significant factors (duration of anesthesia, duration of postoperative intensive care unit stay, wound drainage, increasing patient weight, dirty surgical site, and antimicrobial prophylaxis). CONCLUSIONS: SSI frequency in companion animals is comparable with the frequency observed in human surgical patients. Several significant predictive factors for SSI in small animals surgery were identified. CLINICAL RELEVANCE: Baseline information for SSI surveillance in our hospital and for comparison with other studies was defined. The factors identified may help to predict infections in surgical patients and to take adequate preventive measures for patients at risk.