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61.
Plots in two vineyards in the Golan Heights, Israel were treated with six botryticides during three growing seasons with 3 applications per season. Applications of fenhexamid, pyrimethanil and cyprodinil + fludioxonil were effective, resulting in 52–65% and 53–63% mean reduction in grey mould incidence and severity, respectively. Carbendazim, fluazinam and iprodione were ineffective or slightly effective. Five hundred and sixteen B. cinerea isolates were collected from infected berries or trapped from the air in the vineyards, and profiles of sensitivity to benomyl, fenhexamid, fluazinam, fludioxonil, iprodione and pyrimethanil were established for each of the isolates based on a mycelial growth test. Seventy-four percent of the isolates were sensitive to the six tested fungicides, and the other 26% of the isolates were classified into 10 phenotypes characterized by resistance to one or more fungicides. Resistant isolates showed fitness parameters similar or reduced in comparison to sensitive isolates. Resistance to benzimidazoles and to dicarboximides was the most frequent (up to 25%) and apparently pre-existed in the populations tested. Increased frequency of benzimidazole resistance, but not dicarboximide resistance, was observed following the 3 years of applications of the fungicides. High level resistance to pyrimethanil was present at a frequency of about 2% in both vineyards in the first 2 years of the sampling survey and reached 10% in the third year at Site 2. A few isolates were resistant to fenhexamid or fludioxonil (0.8 or 0.2%, respectively). No strong resistance to fluazinam was detected, although numerous, less sensitive isolates, presumably possessing multi-drug resistance traits, were recovered at higher frequency from the plots treated with fluazinam than from the untreated plots.  相似文献   
62.
Since 1956, when the Basle Zoo (Switzerland) initiated the breeding of lesser kudu (Tragelaphus imberbis), 43% of the lesser kudu juveniles died before reaching an age of 6 mo. In this study, the objective was to obtain the pathological findings, nutritional history, and family tree information in order to evaluate the influence of husbandry on juvenile mortality in these animals. The main cause of death was white muscle disease (WMD), diagnosed in 14 cases (26%) of the deceased juveniles. Although enclosure size had remained constant and animal accessibility to the public was constantly high, both herd size and juvenile mortality had increased from 1956-2004. The diet consumed by the whole group in 2004 had deficient levels of vitamin E and selenium. The increasing linear trend of the mortality rate since the 1960s was significant, and there was a significant correlation between herd size and overall juvenile mortality. In contrast, there was no correlation between herd size and the occurrence of juvenile mortality associated specifically with WMD. Other investigated factors (sex, inbreeding, and season) had no significant effect on overall mortality up to 6 mo of age or on mortality associated with WMD. These results characterize both a dietary and a husbandry problem, and are supported by a lack of similar juvenile mortality in another facility where the diet was supplemented with vitamin E, animal numbers were kept low, and the enclosure structure offered more retreat options for the animals.  相似文献   
63.
Experiments were conducted to assess the effect of gibberellic acid (GA3), a plant growth regulator, on Locusta migratoria migratoria fifth instar larvae. Newly emerged larvae were exposed to various concentrations of GA3 administered by topical application or by forced ingestion. Results showed that treated insects exhibited toxic symptoms with a dose-dependent mortality. GA3 toxicity was also demonstrated by perturbation of the moult processes. In fact, we noted that treated insects present exuviations difficulties due to the impossibility to reject the old integuments causing mortality in the 5th instar larvae. Histological study of proventriculus revealed alterations in the epithelial cells and absence of apolysis phenomenon. Data also showed that GA3 induced significant quantitative variation of haemolymph metabolites. These changes result in a significant decrease in the total concentration of proteins and carbohydrates and an increase in the total concentration of haemolymph lipids.  相似文献   
64.
The improvement in heat tolerance acquired during the acclimatization of laying hens to intermittent heat stress was lost or considerably reduced when energy intake increased following the addition of maize oil to the diet. The oxygen consumption (VO2) of acclimatised hens increased after the addition of maize oil to the diet. Reducing the environmental temperature (Ta) from 30 degrees to 10 degrees C prevented the development of acclimatization if the heat stress commenced soon after the change of Ta; if the heat stress commenced 5 weeks after the change of Ta acclimatization took place normally. Reducing the Ta from 30 degrees to 10 degrees C resulted in an increased VO2 and food intake. The administration of triiodothyronine increased VO2 and reduced the heat tolerance of acclimatised hens. It is concluded that heat tolerance, despite being reinforced by regular exposure to heat stress, remains susceptible to changes in energy metabolism brought about by dietary or environmental means.  相似文献   
65.
Diflubenzuron, topically applied (0·5 μg insect?-1) to Cydia pomonella (L.) at pupal ecdysis disturbed growth and development of oocytes. It delayed the adult ecdysis and caused a decrease in both thickness of the follicular epithelium and the size of the basal oocyte during the pupal development. On the other hand, the size of basal oocytes, the protein content per ovary and the number of oocytes per ovary recorded in newly emerged adults were significantly reduced after diflubenzuron treatment. These results, together with observations in several other species, indicate that the reduction in fecundity and egg viability is probably due to interference of diflubenzuron with the vitellogenesis process.  相似文献   
66.
Crimean–Congo Haemorrhagic Fever (CCHF) is a deadly viral zoonotic disease, which is endemic in Pakistan. We report a case study analysis of three cases of CCHF which occurred in Chakwal, Pakistan in 2016. The disease was suspected in three patients exhibiting clinical symptoms suggestive of CCHF; two of the three patients died. The presence of CCHF was detected by seroconversion (IgG) from the surviving patient, while the antigen was detected in Hyalomma ticks originating from animals in the vicinity. This report indicates increase threat emergence of CCHF in Pakistan and highlights its zoonotic implications requiring immediate interventions under the “One‐Health” concept.  相似文献   
67.
Migratory locusts represent the most important crop pests in Africa and Asia. Because environmental damages are associated with the use of synthetic insecticides in locust and grasshopper control, new environmentally acceptable approaches are becoming increasingly important. The effects of gibberellic acid (GA3), a plant growth regulator, was investigated by topical application and ingestion on the reproductive physiology and ecdysteroids production of the migratory locust Locusta migratoria at concentrations of 125, 625, 3125, 4125, 5125 and 6125 μg/mL. The treatment applied to adult females during the pre-ovipositional phase provokes a significant adverse influence on their reproductive potential. Indeed, GA3 significantly reduced both fecundity and fertility. Gibberellic acid also caused disturbances in the incorporation of the hemolymph metabolites (proteins, carbohydrates and lipids) in the oocyte resulting in a significant reduction in their concentrations in the ovaries. Ecdysteroid production was measured by an enzymo-immunoassay. GA3, administered by ingestion to the adult females, significantly reduced the ecdysteroid titers in ovaries and freshly laid eggs.  相似文献   
68.

Objective

To evaluate intravenous (IV) detomidine with methadone in horses to identify a combination which provides sedation and antinociception without adverse effects.

Study design

Randomized, placebo-controlled, blinded, crossover.

Animals

A group of eight adult healthy horses aged (mean ± standard deviation) 7 ± 2 years and 372 ± 27 kg.

Methods

A total of six treatments were administered IV: saline (SAL); detomidine (5 μg kg?1; DET); methadone (0.2 mg kg?1; MET) alone or combined with detomidine [2.5 (MLD), 5 (MMD) or 10 (MHD) μg kg?1]. Thermal, mechanical and electrical nociceptive thresholds were measured, and sedation, head height above ground (HHAG), cardiopulmonary variables and intestinal motility were evaluated at 5, 15, 30, 45, 60, 75, 90, 120 and 180 minutes. Normal data were analyzed by mixed-model analysis of variance and non-normal by Kruskal–Wallis (p < 0.05).

Results

Nociceptive thresholds in horses administered methadone with the higher doses of detomidine (MMD, MHD) were increased above baseline to a greater degree and for longer duration (MMD: 15–30 minutes, MHD: 30–60 minutes) than in horses administered low dose with methadone or detomidine alone (MLD, DET: 5–15 minutes). No increases in nociceptive thresholds were recorded in SAL or MET. Compared with baseline, HHAG was lower for 30 minutes in MMD and DET, and for 45 minutes in MHD. No significant sedation was observed in SAL, MET or MLD. Intestinal motility was reduced for 75 minutes in MHD and for 30 minutes in all other treatments.

Conclusions

Methadone (0.2 mg kg?1) potentiated the antinociception produced by detomidine (5 μg kg?1), with minimal sedative effects.

Clinical relevance

Detomidine (5 μg kg?1) with methadone (0.2 mg kg?1) produced antinociception without the adverse effects of higher doses of detomidine.  相似文献   
69.
The attachment of two strains of Mycoplasma bovoculi to erythrocytes was measured using 35S-methionine-labelled organisms. Receptor sites of M. bovoculi involved in this attachment are trypsin-sensitive, since mild trypsin treatment of the intact organisms abolished this process completely. Pretreatment of erythrocyt***es with trypsin or increasing concentrations of neuraminidase resulted in no measurable effect. Monoclonal antibody MA25.5 directed against a M. bovoculi surface antigen of 94 kDa termed p94 blocked 40% of the attachment, while MA18.13 directed against a 57 kDa protein band of M. bovoculi had no effect on the attachment process. Other properties of M. bovoculi were tested using six strains of the mycoplasma and erythrocytes from several animal species. None of the strains showed haemagglutinating or haemadsorbing activities.  相似文献   
70.
The basket cockle, Clinocardium nuttallii, is a candidate species for aquaculture in British Columbia, Canada. Previous research on broodstock conditioning, embryonic development and larval rearing of C. nuttallii demonstrated the potential for reliable hatchery production of cockle seed. In this paper, we investigated the effects of culture density (50% and 150% bottom cover in a monolayer) and substratum (none and fine sand) on cockle seed survival, growth, behaviour and shell morphology to improve the efficiency of the nursery production phase. Low stocking density (50% cover) yielded a shell length increase from 3 to 7 mm over a 4‐week period. High stocking density (150% cover) negatively impacted some of the growth and condition parameters studied, but did not have a statistically significant effect on seed survival. Growing seed without substratum did not significantly affect seed survival or growth, but led to shell deformities (at shell length >15 mm) and lower burrowing rates when cockles were subsequently placed on sand. We recommend planting seed for grow‐out at a shell length not exceeding 15 mm. Acclimating seed to the substratum before planting may increase the burrowing rates, thereby reducing the risks of seed dislocation and mortality. Additional studies are required to determine optimal substratum acclimation times and techniques.  相似文献   
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