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41.
OBJECTIVE: To compare the efficacy of collars impregnated with 9% amitraz or 9% amitraz and 0.5% pyriproxyfen (PPF) for control of newly established tick infestations by Rhipicephalus sanguineus, Ixodes ricinus, and Ixodes scapularis in dogs and determine whether egg production by surviving female ticks was decreased. DESIGN: Prospective study. ANIMALS: 72 dogs. PROCEDURE: Dogs were fitted with 1 of 3 test collars impregnated with amitraz, amitraz and PPF, or only excipients (untreated controls). In 3 trials corresponding to each of the 3 tick species, dogs were infested with 150 unfed adult ticks on days 8, 10, 13, and 18. The number of feeding female ticks was recorded on days 10, 13, 18, and 28. Surviving females were weighed and permitted to oviposit under controlled conditions. RESULTS: Collars impregnated with amitraz and PPF decreased tick loads as efficiently as collars containing amitraz alone. Inclusion of PPF into the collar did not significantly decrease the efficacy of amitraz. The few female ticks that survived after feeding on dogs treated with collars containing PPF were unable to oviposit. CONCLUSIONS AND CLINICAL RELEVANCE: Collars impregnated with amitraz were efficient in preventing tick infestations in dogs but did not inhibit oviposition in the few surviving female ticks. Incorporation of PPF into the amitraz-impregnated collar resulted in impairment of the reproductive ability of ticks. 相似文献
42.
In a swine production herd dwarfs with extremely short limbs were observed in 3 litters sired by the same boar. Clinical, radiographical, and pathologic-anatomical examinations, showed the affected individuals to be chondrodysplastic dwarfs. Such dwarfism has not been reported previously in pigs. An inbreeding experiment conducted with a dwarf gilt and related boars indicated that the dwarfism was hereditary with a simple autosomal recessive inheritance. 相似文献
43.
Field monitoring and scenario-based modelling were used to assess exposure of small ditches in the UK to the herbicide sulfosulfuron following transport via field drains. A site in central England on a high pH, clay soil was treated with sulfosulfuron, and concentrations were monitored in the single drain outfall and in the receiving ditch 1 km downstream. Drainflow in the nine months following application totalled 283 mm. Pesticide lost in the first 12.5 mm of flow was 99% of the total loading to drains (0.5% of applied). Significant dilution was observed in the receiving ditch and quantifiable residues were only detected in one sample (0.06 microg litre(-1)). The MACRO model was evaluated against the field data with minimal calibration. The parameterisation over-estimated the importance of macropore flow at the site. As a consequence, the maximum concentration in drainflow (2.3 microg litre(-1)) and the total loading to drains (0.76 g) were over-estimated by factors of 2.4 and 5, respectively. MACRO was then used to simulate long-term fate of the herbicide for each of 20 environmental scenarios. Resulting estimates for concentrations of sulfosulfuron in a receiving ditch were weighted according to the prevalence of each scenario to produce a probability distribution of daily exposure. 相似文献
44.
Kenichi?TsuchiyaEmail author Christophe C.M.?d’Ursel Yuzo?Nozu 《Journal of General Plant Pathology》2004,70(1):27-33
Bacterial black spot disease of mango is caused by Xanthomonas campestris pv. mangiferaeindicae (Xcm), which consists of two genotypically and phenotypically distinct groups of strains. Monoclonal antibodies (MABs) were produced – 15 against CFBP 1717, a group I strain, and 9 against CFBP 2919 (yellow-pigmented), a group II strain – and were analyzed for their characteristics. On the avidin-biotin peroxidase complex enzyme-linked immunosorbent assay, the dilution limit of the MABs was between 100 and 200000 and was 10 times higher when measured on the corresponding ascitic fluid. All kinds of isotypes were represented among the MABs. All the Japanese Xcm strains, designated group I by hrp-restriction fragment length polymorphism (RFLP) analysis, reacted equally with MAB 1A7H12G3, which is the most specific for all but one worldwide group I strains, and to only one strain among group II. Also, to various extents, serological heterogeneity inside the two groups was consistently differentiated based on isozyme and RFLP analyses. MAB 1E2E1 against CFBP2919, because of its narrow specificity, and MAB 1A7H12G3 against CFBP1717, because of its broad specificity, will be useful for epidemiological studies or general control of the pathogen. 相似文献
45.
Castro-Hermida JA Pors I Otero-Espinar F Luzardo-Alvarez A Ares-Mazás E Chartier C 《Veterinary parasitology》2004,120(1-2):35-41
The efficacy of orally administered tablets containing alpha-cyclodextrin, an excipient used in the pharmaceutical industry with demonstrated anticryptosporidial activity in vitro and in neonatal mice, was evaluated in neonatal goat kids. The formulation was evaluated for hardness and was subjected to in vitro drug release studies. Twenty goat kids were orally inoculated with 10(6) oocysts of C. parvum within the first 6 days of age. Half of the animals were treated by oral administration of four tablets of alpha-cyclodextrin/day (500 mg/kg of body weight) for six consecutive days, the treatment beginning on the day of inoculation. Infection was monitored by daily examination of faecal samples from the first day to 25 days post-inoculation. The criteria studied in evaluating efficacy were: oocyst shedding, presence of diarrhoea and weight gain at 15 and 25 days post-inoculation. alpha-cyclodextrin was effective when given at the beginning of infection: there was a longer pre-patent period, a reduction in the patent period and a decrease in the intensity of infection, these differences being statistically significant (P < 0.05) compared with untreated neonatal kids. Moreover, except in one animal, the diarrhoea was prevented in infected neonatal kids. Animals from both groups increased the body weight and no significant differences were seen between the two groups. 相似文献
46.
Proteome analysis of the sarcoplasmic fraction of pig semimembranosus muscle: implications on meat color development 总被引:2,自引:0,他引:2
Sayd T Morzel M Chambon C Franck M Figwer P Larzul C Le Roy P Monin G Chérel P Laville E 《Journal of agricultural and food chemistry》2006,54(7):2732-2737
Two-dimensional electrophoresis was used to investigate sarcoplasmic protein expression in pig Semimembranosus muscles sampled 20 min after slaughter. Two groups (light and dark) of 12 animals were selected from 1000 pigs, based on meat L values measured 36 h postmortem. Twenty-two proteins or fragments (p < 0.05) were differentially expressed. Muscles leading to darker meat had a more oxidative metabolism, indicated by more abundant mitochondrial enzymes of the respiratory chain, hemoglobin, and chaperone or regulator proteins (HSP27, alphaB-crystallin, and glucose-regulated protein 58 kDa). Conversely, enzymes of glycolysis were overexpressed in the lighter group. Such samples were also characterized by higher levels of glutathione S-transferase omega, which can activate the RyR calcium channels, and higher levels of cyclophilin D. This protein pattern is likely to have severe implications on postmortem metabolism, namely, acceleration of ATP depletion and pH fall and subsequent enhanced protein denaturation, well-known to induce discoloration. 相似文献
47.
Dornez E Joye IJ Gebruers K Delcour JA Courtin CM 《Journal of agricultural and food chemistry》2006,54(11):4028-4034
The endoxylanases associated with wheat kernels consist of wheat endogenous endoxylanases on one hand and kernel-associated microbial endoxylanases on the other hand. Assessment of their presence, based on analysis of their enzymic activity, can be expected to be hampered by the presence in wheat of high levels of endogenous endoxylanase inhibitors, which are able to inhibit the wheat-kernel-associated microbial endoxylanases. On the basis of preliminary experiments aimed at clarifying the distribution of the wheat-associated endoxylanases, a method to estimate total endoxylanase activities in wheat kernels was developed. Extensive washing of wheat kernels with universal buffer of pH 8.0 provided near-quantitative separation of the microbial endoxylanases located on the surface of wheat kernels from the endogenous endoxylanases and endoxylanase inhibitors located in such kernels. The microbial or endogenous nature of the endoxylanases was confirmed by making use of the inhibition specificity of endoxylanase inhibitors. Determination of the endoxylanase activity in the washing liquid, corresponding to the microbial endoxylanase population, and the washed kernels, corresponding to the endogenous endoxylanase population, allowed estimation of the total endoxylanase activities associated with the wheat kernel. Results showed that microbial endoxylanases can account for over 90% of the total wheat-associated endoxylanase activity and that the latter can be at least 5 times higher than the apparent endoxylanase activity. 相似文献
48.
Dornez E Gebruers K Wiame S Delcour JA Courtin CM 《Journal of agricultural and food chemistry》2006,54(22):8521-8529
To gain insight into the distribution of arabinoxylans (AX), endoxylanases, and endoxylanase inhibitors in industrial wheat roller milling, all streams, that is, 54 flour fractions, 4 bran fractions, and the germ, were analyzed for ash, starch, and protein contents, alpha-amylase activity levels, total (TOT-AX) and water-extractable arabinoxylan (WE-AX) contents, endoxylanase activity levels, and endoxylanase inhibitor (TAXI and XIP) contents. In general, bran fractions were significantly richer in TOT-AX and WE-AX contents, endoxylanase activity levels, and endoxylanase inhibitor contents than germ and, even more so, than flour fractions. In the 54 different flour fractions, minimal and maximal values for TOT-AX and WE-AX contents differed by ca. 2-fold, whereas they differed by ca. 15-fold for endoxylanase activity levels. The latter were positively correlated with ash and negatively correlated with starch content, suggesting that the endoxylanase activity in flour is strongly influenced by the level of bran contamination. TAXI contents in the flour fractions varied ca. 4-fold and were strongly correlated with bran-related parameters such as ash content and enzyme activity levels, whereas XIP contents varied ca. 3-fold and were not correlated with any of the parameters measured in this study. The results can be valuable in blending and optimizing wheat flour fractions to obtain flours with specific technological and nutritional benefits. 相似文献
49.
Grassly NC Fraser C Wenger J Deshpande JM Sutter RW Heymann DL Aylward RB 《Science (New York, N.Y.)》2006,314(5802):1150-1153
The feasibility of global polio eradication is being questioned as a result of continued transmission in a few localities that act as sources for outbreaks elsewhere. Perhaps the greatest challenge is in India, where transmission has persisted in Uttar Pradesh and Bihar despite high coverage with multiple doses of vaccine. We estimate key parameters governing the seasonal epidemics in these areas and show that high population density and poor sanitation cause persistence by not only facilitating transmission of poliovirus but also severely compromising the efficacy of the trivalent vaccine. We analyze strategies to counteract this and show that switching to monovalent vaccine may finally interrupt virus transmission. 相似文献
50.