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71.
The present study reports the sublethal effects of the entomopathogenic fungus, Aschersonia aleyrodis(Webber) on Bemisia tabaci(Gennadius)(Homoptera: Aleyrodidae). A fungal suspension of A. aleyrodis isolate Aa005 containing 1×107 conidia mL~(–1) was sprayed against B. tabaci on eggplant leaves under greenhouse conditions. The effects of fungal application on survival as well as life table parameters of the whitefly were observed at different post inoculation periods. The results indicated that A. aleyrodis can significantly affect the survival of 1st, 2nd, and 3rd nymphal instars of B. tabaci. Developmental periods of different instar nymphs were not affected by fungal application. A. aleyrodis spores persisted well and significantly affected the survivorship of young instar nymphs of B. tabaci at different post incubation periods. Life table results suggested that A. aleyrodis has no impact on general fecundity and longevity of B. tabaci. When the pathogen was exposed to the open environment and maintained for a relatively longer period, a reduction in the reproductive rate and intrinsic rate of increase was caused by the fungal spores, though the sublethal effects were not as good as the control treatment. The results suggest that the ability of spores to suppress an increase in whitefly population persists well after incubation of spores to the external environment(up to 9 days).  相似文献   
72.
This paper presents the effects of particle size and mixing ratio on the properties including physical, mechanical, and decay resistance of wood plastic composites (WPCs). In addition, it also presents the effects of immersion temperatures on water absorption (WA) and thickness swelling (TS) of the WPCs. WPCs with a thickness of 6 mm were fabricated from Albizia richardiana King & Prain wood particles and recycled polyethylene terephthalate (PET) by the flat-press method. To prepare the WPCs, two different wood particle sizes (0.5–1.0 and 1.01–2.0 mm) were used along with four different mixing ratios (w/w). Subsequently, the physical properties include density, moisture content, WA, and TS, and mechanical properties include modulus of elasticity (MOE) and modulus of rupture (MOR) of the produced WPCs was evaluated. Furthermore, decay resistance was evaluated by the weight loss percentage method. Moreover, the effects of immersion temperatures on WA and TS of WPCs after 24 h of immersion in water at three different temperatures, i.e., 25, 50, and 75 °C were investigated. Results showed that the wood particle size had impact on WPC’s density (only 6% decreased with the increase of particle size); however, the density decreased by 29% when the wood particle content increased from 40 to 70%. The WA and TS gradually increased with the increase of particle content and decrease of particle size. In addition, WA and TS increased proportionately with increasing immersion temperature from 25 to 75 °C. Furthermore, the highest MOE (2570 N/mm2) was found for the WPCs fabricated from large wood particles having the ration of 50:50 (wood particle:PET). For decay resistance, WPCs consisted of larger particles and higher PET content showed greater resistance against decay. Therefore, it is comprehensible that fabrication of the WPCs from 50% large particles and 50% PET is technically feasible and further improvement of WPC performance like enhancement of MOE and reduction of density using coupling agent and agricultural waste fibers, respectively, in the WPC formulation is recommended.  相似文献   
73.
Stevia (Stevia rebaudiana Bertoni) is a perennial and subshrub herb of the Asteraceae family, which originates from South America. Stevia has long been used as a sweetener and herbal medicine throughout the world. The most important feature of stevia is its sweetness with zero calories. This natural feature of Stevia is of utmost importance to everyone, especially those with diabetes and those who diet. In this study, samples were taken from Stevia rebaudiana plants of different ages (2, 3 and 4 years) in different growth periods (H1: 1 July, H2: 1 August, H3: 1 September and H4: 1 October) and an evaluation was made on the nutritional content values, the chlorophyll and sugar rates found in these samples according to the age and growth period of the plant. It was determined that the age of the plant and the harvesting period had an effect on the macro-micro nutritional elements, and chlorophyll and steviol glycoside rates contained in the stevia plant. In addition, as a result of correlation analysis, significant correlations were determined between the parameters measured in the plant. The results of the study demonstrated that in the cultivation of stevia, the best values were obtained from plants that were 3 years old and harvested in July.  相似文献   
74.
This paper describes clinical findings and surgical treatment of a foal with multiple craniofacial defects (glossocheilognathoschisis; congenital midline cleft of the lower lip, mandible and tongue combined with bilateral persistent frenula linguae) admitted to the Surgery Clinics of Faculty of Veterinary Medicine, University of Kafkas, Turkey. A thorough clinical examination revealed cleft of the lower lip and mandible combined with glossoschisis (glossocheilognathoschisis) and bilateral extensive and restrictive membranous band (frenula) of tissue at the base of the tongue. Physical examination and radiography of the other organs and tissues of the foal were within normal limits. After sedation and general anesthesia, the persistent frenulas on the right and left parts of the tongue were transected, starting from normal tongue tissue, with the scissors. The tongue was completely freed after the transection of the remaining part of the frenulum, where right and left frenulas united, and the accompanying mucosal tissue on the mandibular symphysis was removed and underlying bone tissue was superficially curetted. Cerclage wire was placed under the mucosa of the mandible and was then passed among two drilled holes below the two incisors. These two pieces of wire were twisted together and anchored over the labial surface of the mandibular symphysis junction. The mandibular symphysis was then stabilized after cerclage wire tensing. A nasogastric tube was placed to permit enteral feeding. The foal was discharged 5 days after surgery. Telephone follow-up revealed that the foal had died 15 days after the surgical intervention.  相似文献   
75.
Rectal swabs from 100 dogs that were admitted to the veterinary clinic and from randomly selected 100 dogs from one kennel were examined for the presence of Salmonella spp. S. Enteritidis was isolated from a household dog and the strain was susceptible to all antibiotics that were tested. S. Typhimurium was isolated from a dog from the kennel and it was sensitive to all the antibiotics except streptomycin and neomycin. Even though, the occurence of Salmonella spp. in the feces of the dogs in this study was low, attention should always be given when handling canine feces or contaminated materials.  相似文献   
76.
This paper compared antibiotic sensitivity between Vibrio spp. isolated from diseased postlarval and marketable-sized white leg shrimp (Litopenaeus vannamei). Recently, white leg shrimp become target species of shrimp culture among shrimp farmers in Malaysia to replace tiger shrimp (Penaeus monodon) culture. However, the baseline information on antibiogram of pathogenic bacteria especially Vibrio spp., the causative agent of vibriosis in white leg shrimp culture is not well established. Therefore, this study was conducted to reveal the antibiogram of Vibrio spp. isolated from diseased postlarval and marketable-sized white leg shrimp. The information gained from this study is useful for shrimp farmers in selecting appropriate antibiotic during disease outbreak. Antibiogram of present bacterial isolates was determined through disk diffusion method against 21 antibiotics (oxolinic acid 2 μg, ampicillin 10 μg, erythromycin 15 μg, furazolidone 15 μg, lincomycin 15 μg, oleandomycin 15 μg, amoxicillin 25 μg, colistin sulphate 25 μg, sulphamethoxazole 25 μg, chloramphenicol 30 μg, doxycycline 30 μg, florfenicol 30 μg, flumequine 30 μg, kanamycin 30 μg, nalidixic acid 30 μg, novobiocin 30 μg, oxytetracycline 30 μg, tetracycline 30 μg, nitrofurantoin 50 μg, fosfomycin 50 μg, and spiramycin 100 μg). A total of 47 Vibrio spp. isolates (Vibrio parahaemolyticus, 24, and V. alginolyticus, 23) from postlarval white leg shrimp and 49 Vibrio spp. isolates (Vibrio parahaemolyticus, 13, Vibrio alginolyticus, 28, and luminous Vibrio parahaemolyticus, 8) from marketable-sized white leg shrimp were successfully identified. Results of antibiotic sensitivity test from the present study showed that more than 80% Vibrio spp. from diseased postlarval and marketable-sized white leg shrimp, respectively, were sensitive to 14 out of the 21 tested antibiotics. Vibrio spp. isolated from marketable-sized white leg shrimp were found more susceptible to the tested antibiotics than Vibrio spp. isolated from postlarval white leg shrimp. This was due to 100% sensitive case against eight antibiotics found among Vibrio spp. isolated from marketable-sized white leg shrimp, whereas only three antibiotics were found sensitive to all Vibrio spp. isolated from postlarval white leg shrimp. Furthermore, the multiple antibiotic resistance (MAR) index indicated that marketable-sized white leg shrimp were not under high risk exposure to the tested antibiotics. On the other hand, the postlarvae were highly exposed to the tested antibiotics.  相似文献   
77.
Cawson  Jane G.  Hemming  Victoria  Ackland  Andrew  Anderson  Wendy  Bowman  David  Bradstock  Ross  Brown  Tegan P.  Burton  Jamie  Cary  Geoffrey J.  Duff  Thomas J.  Filkov  Alexander  Furlaud  James M.  Gazzard  Tim  Kilinc  Musa  Nyman  Petter  Peacock  Ross  Ryan  Mike  Sharples  Jason  Sheridan  Gary  Tolhurst  Kevin  Wells  Tim  Zylstra  Phil  Penman  Trent D. 《Landscape Ecology》2020,35(8):1775-1798
Landscape Ecology - Fire behaviour research has largely focused on dry ecosystems that burn frequently, with far less attention on wetter forests. Yet, the impacts of fire in wet forests can be...  相似文献   
78.
The optimum dietary protein requirement of the Malaysian mahseer (Tor tambroides) fingerlings was determined in this study. In this completely randomized designed experiment, formulated diets of five levels of dietary protein (30, 35, 40, 45 and 50%) were tested on the T. tambroides fingerlings (initial body weight of 5.85 +/- 0.40 g), reared in aquarium fitted with a biofiltering system. The fingerlings were fed twice daily at 5% of biomass. The fingerling body weight and total length was taken at every two weeks. Mortality was recorded daily. The dietary protein had significant effects on the body weight gain and Specific Growth Rate (SGR) of the fingerlings. The body weight gain and SGR of fingerlings fed with the diet with the dietary protein level of 40% was significantly higher (p<0.05) than that of 30, 35 and 50%. The feed conversion ratio of the 40% dietary protein was the significantly lowest at 2.19 +/- 0.163. The dietary protein level of 40% was the most optimum for T. tambroides fingerlings.  相似文献   
79.
As no information is available regarding the efficacy of using rice protein concentrate (RPC) to replace fishmeal (FM) in diets for European sea bass (Dicentrarchus labrax), a trial was conducted to determine the optimum inclusion for European sea bass juveniles. Diets were formulated to replace 25%, 50% and 75% of fishmeal with RPC. Additional high level inclusion diets (50% and 75%) were supplemented with lysine and methionine to determine if these were limiting factors. Fish (18.0 ± 0.06 g) were fed the experimental diets for 12 weeks. The final mean weight and specific growth rate (SGR) were significantly higher in fish fed the control diet (diet FM) and low level RPC (diet RPC25) than in fish fed the other diets. The supplementation of the amino acids had a positive effect on growth, elevating the final weight of the high level RPC (RPC75 + AA) group above that of the non‐supplemented group (RPC75). However, this was still not comparable to fish fed FM and RPC25 diets. No significant differences in body composition were observed. A digestibility study demonstrated an inverse relationship between elevating inclusion levels of RPC and apparent digestibility coefficients (ADCs) for dry matter and lipid, with significantly lower values than the control being observed with RPC inclusions above 25%. The mesenteric fat index followed this trend. Circulating leucocyte levels, leucocyte ratios and serum lysozyme activity remained unaffected by dietary treatment. However, compared with the control group, fish fed RPC75, RPC50 + AA RPC75 + AA displayed significantly lower haematocrit values. The present study demonstrates that the inclusion of RPC at 140 g kg?1 (effectively replacing 25% of FM content) does not compromise European sea bass growth performance, body quality or basic haematological parameters. It is suggested that future studies including higher levels test the efficacy of additional amino acid supplementation (e.g. tryptophan).  相似文献   
80.
ABSTRACT: Suffolk sheep carrying the DRB1*1101 (previously referred to as-DRB1*0203 or G2) allele have been reported to show increased resistance to natural Teladorsagia circumcincta infection compared to non-carriers. The objective of this study was to compare the biochemical and physiological responses of DRB1*1101 carrier and non-carrier twin lambs to an experimental infection with 3 × 104 L3 Teladorsagia circumcincta. The variables studied included worm burden, faecal egg count, abomasal mast cells, IgA, IgE, IgG1 plus IgG2 and haematological parameters at 0, 3, 7, 21 and 35 days post infection (dpi), and duodenal smooth muscle contractility at 0 and 35 dpi. DRB1*1101 carrier lambs had significantly lower worm burden, higher mast cell and plasma platelet counts than the DRB1*1101 non-carriers (P < 0.05). Before infection, the non-carrier lambs exhibited significantly higher mucosal levels of all antibody isotypes measured compared to the carriers; these levels remained relatively stable over the course of infection in the non-carriers while there was a slow build up of these antibodies in the carriers up to day 21 post infection (pi). The DRB1*1101 non-carrier lambs had a significantly higher plasma lymphocyte count, and produced greater duodenal contractile force relative to the carrier lambs (P < 0.05). There was no significant difference between genotypes in the level of plasma eosinophils, monocytes, neutrophils or FEC. This evidence suggests that resistance conferred by DRB1*1101 is acquired rather than innate, depends on worm expulsion rather than fecundity and is dependent on mucosal mast cell proliferation, platelet activation, and IgA and IgE antibody responses.  相似文献   
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