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51.
The objective of this work was to estimate the abundance, diversity and constancy of families from the order Hymenoptera, such as the seasonality of those through a survey on the insect population in a silvopastoral system. We installed a Malaise-type trap in a Brachiaria decumbens area managed by a silvopastoral system in Coronel Pacheco, MG, from August 2006 to July 2008. The trapped insects were screened, and those of the order Hymenoptera were classified into their respective family categories and quantified. We adopted the methodology of Bodenheimer to calculate the indices of constancy, while other indices were estimated PAST program. We sampled 5841 specimens in total, which included 549 morphospecies and were distributed among 11 families. Of the total specimens sampled, 80% were Formicidae, which besides being the most abundant, was also the most diverse and constant family. When entomophagous insects were analyzed, the highest values for these indices were recorded for the families Ichneumonidae, Braconidae, and Vespidae. Pollinators were less prevalent compared to the total number of sampled individuals. The population density in the Hymenoptera was not correlated between the two sampling years and climate factors.  相似文献   
52.
Five proprietary and one experimental dressing were compared with no treatment in their ability to aid healing of mulesing wounds in over 1900 young lambs. Healing was judged as the completeness of shrinkage of the mulesing cuts and the condition of scabs on the new skin surface. When assessed at 21 d it was found that treatment with Heriots Crown Wound Powder or Coopers Mulesing Powder offered a significant advantage over leaving the wounds untreated. Neither aqueous organophosphate washes, Defiance nor Defiance containing 0.08% chlorfenvinphos offered any healing advantage over controls. However, washing the wounds with an aqueous organophosphate solution aided healing more than the Defiance-based dressings. It was considered that the powders or the washes encouraged quick scab formation either by creating a dry covering (powders) or by washing away blood and allowing fast drying of the wound. The Defiance-type dressings slowed healing by keeping the wound moist for up to 10 d, but healing was not significantly different to the untreated group by 21 d.  相似文献   
53.
During the last decade, oral cyclosporin (CsA) has proven to be effective, in randomized controlled trials, for the treatment of atopic dermatitis (AD) in human patients. The purpose of this blinded randomized controlled trial was to test the hypothesis that CsA was successful in reducing the gravity of clinical signs of AD in dogs. Thirty dogs with nonseasonal AD were randomly allocated to receive an oral solution of either NEORAL CsA (5 mg kg-1) or prednisolone (0.5 mg kg-1) once daily for 6 weeks. Before, and 3 and 6 weeks after therapy, skin lesions were graded by clinicians using the Canine AD Extent and Severity Index (CADESI). Pruritus was assessed by the owners using a visual analog scale (PVAS). In both groups, CADESI and PVAS values were significantly lower at 6 weeks post treatment than before the initiation of therapy (Friedman test, P < 0.0004). The percentage reductions in CADESI and PVAS values from baseline were not statistically different between groups (Mann-Whitney test, P > 0.3). In this experiment, the tolerability and safety of oral CsA and prednisolone appeared similar. One-fifth of dogs given oral CsA occasionally developed diarrhoea or soft stools. One dog that was given CsA developed a generalized papillomatous skin eruption during the second half of the trial. Our study provides randomized controlled trial evidence that CsA reduces the severity of clinical signs in dogs with nonseasonal AD. Moreover, the anti-allergic efficacy of CsA appears comparable with that of prednisolone. We propose that oral CsA should be considered as a valuable alternative to glucocorticoid therapy in dogs with AD.  相似文献   
54.
OBJECTIVE: To evaluate risk behaviors for transmission of zoonotic diseases at petting zoos during a period without a recognized disease outbreak. DESIGN: Observational survey with environmental microbiologic sampling. SAMPLE POPULATION: 6 petting zoos in Tennessee. PROCEDURES: Attendees were observed for animal and environmental contact, eating or drinking, hand-to-face contact, and use of a hand sanitizer. Hands were examined via bacteriologic culture on some attendees. Environmental samples were collected at three petting zoos. RESULTS: 991 attendees were observed; of these, 74% had direct contact with animals, 87% had contact with potentially contaminated surfaces in animal contact areas, 49% had hand-to-face contact, and 22% ate or drank in animal contact areas. Thirty-eight percent used hand sanitizer; children had better compliance than adults. Results of bacteriologic cultures of hands were negative for Salmonella spp and Escherichia coli O157; Salmonella spp were isolated from 63% and E coli O157 from 6% of the environmental samples. CONCLUSIONS AND CLINICAL RELEVANCE: High risk behaviors were common among petting zoo visitors, and disease prevention guidelines were inconsistently followed. This is an example of the importance of one-medicine, one-health initiatives in protecting the public health. Veterinarians, venue operators, and public health authorities must work together on targeted education to improve implementation of existing disease prevention guidelines.  相似文献   
55.
Shinji  Junpei  Nohara  Setsuo  Yagi  Nobuyuki  Wilder  Marcy 《Fisheries Science》2019,85(6):1055-1065
Fisheries Science - Crustacean aquaculture is a multibillion-dollar industry worldwide that continues to show significant growth. Shrimp farming has been intensified for decades, and...  相似文献   
56.
Changes in crustacean hyperglycemic hormone (CHH)-family peptides in response to stress were investigated in Litopenaeus vannamei. Stress treatments consisted of air exposure and low salinity. High-performance liquid chromatography was used to quantify CHH-family peptides in the X-organ?Csinus gland complex (XO?CSG) in the eyestalks. Among the CHH-family peptides analyzed, only the level of sinus gland peptide-G (SGP-G) in the XO?CSG was decreased. SGP-G was also detectable by Western blotting analysis in the hemolymph of animals subjected to stress. These results suggest that SGP-G was secreted from the XO?CSG into the hemolymph during stress. Glucose levels in the hemolymph increased under conditions during which SGP-G was detected in the hemolymph. Hyperglycemia was also observed when SGP-G was injected. SGP-G may function to shift energy use to deal with stress.  相似文献   
57.
Changes in hemolymph osmolality, ion concentrations, and enzymatic activities of carbonic anhydrase (CA) in the gills and epidermal tissue, and Na/K-ATPase in the gills during the molt cycle were investigated in the white shrimp Litopenaeus vannamei. Hemolymph osmolality was high in the intermolt and early premolt stages, but started to decrease prior to ecdysis through to postmolt stages A and B. Changes in Na+ and Cl ion concentrations paralleled those in hemolymph osmolality. CA activity levels in the anterior and posterior gills were low at intermolt stage C0 and premolt stage D0, and maximum at premolt stage D3. In the epidermal tissue, activity was relatively high at intermolt stage C0 and premolt stage D0, but fluctuated towards premolt stage D3 and postmolt stage A. On the other hand, Na/K-ATPase activity in the gills decreased between intermolt stage C0 and premolt stage D2, but increased at premolt stage D3 and postmolt stage A. The changes in patterns of CA activity during the molt cycle suggest that CA may be involved in supplying counter-ions for Na+ and Cl uptake during molting. Branchial Na/K-ATPase appears to be involved in producing local osmotic gradients in order to support water influx across the epithelium.  相似文献   
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59.
Eyestalk ablation is often used to induce ovarian development in female shrimp, but it possibly alters the animal’s hormonal balance, and affects its physiology and immune system. Therefore, this study was conducted to investigate alterations to the immune response during induced ovarian development by unilateral and bilateral ablation in Litopenaeus vannamei. Sub-adult female shrimp could be induced to undergo ovarian development over a 20-day period by both unilateral and bilateral eyestalk ablation; however, ovaries did not reach the final mature stage in which cortical rods are observed. In terms of immune response, total hemocyte count decreased significantly at 4 h after unilateral ablation, and at 20 days after bilateral ablation. After 20 days, expression in the hemocytes of the immune-related genes prophenoloxidase and peroxinectin in bilaterally ablated shrimp increased significantly, whereas that for penaeidin, for lipopolysaccharide- and β-glucan-binding protein, and for transglutaminase mRNA expression did not change significantly. The results of this study suggest that, while eyestalk ablation induces ovarian development, it may also bring about a hormonal imbalance that leads to immune-related genes being activated.  相似文献   
60.
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