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1.
沙罗拉纳(sarolaner)属异恶唑啉类化合物,是一种新型广谱杀虫药。沙罗拉纳已被证实通过特异性阻断昆虫γ-氨基丁酸受体和谷氨酸门控氯离子通道而显示出抗寄生虫活性。本文综述了近年来沙罗拉纳在国外伴侣动物体外寄生虫防治中的开发及临床应用情况,旨在为该药的深入研究和国内开发应用提供参考。近年来,该药主要用于犬猫等伴侣动物体外寄生虫的临床预防和治疗,对蜱类、蚤类、螨类等体外寄生虫有高效的杀灭作用。与其他杀虫药相比,该药在分子结构、作用位点和选择性等方面有显著差异,具有杀虫活性强、治疗剂量低、安全性高等优点。此外,该药通过与多种药物联合应用,可提高治疗效果,扩大治疗范围。就国外研究来看,沙罗拉纳是一种安全广谱的高效杀虫剂,拥有广阔的应用前景。 相似文献
2.
Peter B. Best 《African Zoology》2013,48(2):177-179
The catch per unit effort of Oreochromis mossambicus, Clarias gariepinus and Cyprinus carpio at different localities at Hartbeespoort Dam was investigated. Catches of the three species were between three and ten times higher on the southern shore of the lake than on the northern shore. The gradient of each locality was found to be the most important variable determining catch. Gill-net catches of O. mossambicus from littoral and limnetic stations indicated equal abundance of the species in these two habitats. The implications of the results for improved predictions of fish yield from lakes, and for management are discussed. 相似文献
3.
《African Zoology》2013,48(3):107-111
Enteromius mattozi Guimaraes, 1884, a popular eating fish among local people, were examined for monogenean parasites as part of a larger study to ascertain the feasibility of establishing aquaculture production in Limpopo, South Africa. In this study a new monogenean parasite of the genus Dactylogyrus was collected from the gills of E. mattozi, and described. It differs from known species of this group in the shape, size and structure of the heavily sclerotized vaginal prop. The proximal end of the vaginal prop has three layers similar to stacked funnels of decreasing sizes leading into a tube. The male copulatory organ is also much larger and robust than those of related species. The name Dactylogyrus mattozii is proposed for this new species. 相似文献
4.
Stephen Jess Sally L
B Kidd Trevor McCallion David I Matthews 《Pest management science》2000,56(12):995-1004
This is the third survey of control practices for ectoparasites on sheep farms in Northern Ireland, providing data comparative to those recorded in previous surveys in 1981 and 1988. Data relating to all aspects of ectoparasite control were collected from 210 farms representing 4% of the total sheep population. Quantitative data have been adjusted to provide accurate estimates of total pesticide usage. Since the previous survey in 1988, the number of sheep farms in Northern Ireland has increased by 10% to 11 692 with a consequent 39% increase in sheep population to 2.9 million. Despite this level of expansion, the total quantity of organophosphorus compounds used for ectoparasite control has remained approximately constant at 7–8 tonnes. The report considers that compulsory sheep‐dipping, prescribed since 1970 and revoked in 1993, impacted significantly on subsequent ectoparasite control practices and consequent pesticide usage. During 1997, approximately 20% of sheep farmers relied on alternative methods to control ectoparasites, including injectable formulations of avermectins and pour‐on formulations of insect growth regulators and pyrethroids. Dipping formulations containing pyrethroid compounds, which accounted for <1% of treatments in 1988, increased to 9% in 1997. Previously, regulatory sheep‐dipping periods were specified during the autumn months, which tended to increase dipping frequency. The majority of farmers dipping sheep during the summer strictly for blowfly maggot (Diptera: Calliphoridae) control were required to perform additional compulsory sheep‐dipping during the autumn. Withdrawal of compulsory sheep‐dipping has allowed farmers to synchronise dipping practices to control the major ectoparasites of sheep at a single dipping occasion. An estimated 7.5 × 106 litres of surplus dipwash required disposal and there were approximately equal numbers of farmers disposing dipwash immediately after sheep‐dipping or on occasions up to and including subsequent dipping. The decline in the number of farmers who allowed dipwash to run‐off into soakaways or surrounding soil observed in 1988 continued in 1997. The majority of farmers used tractor‐operated pumps to dispose of dipwash into slurry tanks for subsequent disposal onto permanent pasture. © Crown copyright 2000. Reproduced with the permission of Her Majesty's Stationery Office. Published for SCI by John Wiley & Sons, Ltd. 相似文献
5.
Adult and preadult Dissonus manteri attached to the gills of Plectropomus leopardus cause significant pathology in the form of large hyperplastic nodules on the afferent (leading) edges of gill filaments. Nodules result from the dual actions of parasite attachment and feeding. The host response is characterized by severe epithelial hyperplasia, supplemented by fibroplasia and inflammation. Parasites attach close to the gill arch near the base of filaments. They have little effect on gill vasculature as the maxillipeds penetrate the filament superficial to the efferent filament artery and do not interfere with the blood vessels of the secondary lamellae. Tissue proliferation is limited to the wide portion of filament 'edge' epithelium in the proximal third and also does not extend to the secondary lamellae. Nodules are most numerous towards the ends of hemibranchs and are generally absent from the central regions. Leading hemibranchs bear significantly more nodules than their trailing counterparts. Of the total number of nodules, 20.5% are located on the pseudobranchs. Distribution patterns are considered to be primarily the result of D. manteri avoiding strong water currents, although this cannot explain the difference between numbers on leading and trailing hemibranchs. 相似文献
6.
Samantha Bui Frode Oppedal Velimir Nola Luke T. Barrett 《Journal of fish diseases》2020,43(6):697-706
Problematic sea lice infestations on farmed Atlantic salmon (Salmo salar) have motivated extensive research and development into new methods to prevent, monitor and control sea lice. Most of these technologies require detailed information on the behaviour, spatial distribution and demography of lice on host fish. This study investigated how salmon lice (Lepeophtheirus salmonis) infestation density varies across the host's surface under sea cage farming conditions. Lice abundance, demography and attachment location were tracked over time, with repeated sampling of 300 individually tagged salmon across three replicate experimental sea cages. The data reveal clear differences in attachment locations according to sex and stage, but with an overall preference for the dorsal surface among mobile stages—dorsal head for adult females and dorsal-posterior section for males and pre-adults. Total lice abundance was highly variable between repeated measures of individual fish, consistent with frequent host-switching or mortality. Total lice numbers also declined between sampling dates, likely due to handling, with lost mobile lice being almost exclusively adult males. As the distribution of sea lice on hosts is likely determined by numerous factors, future image-based automated detection systems should be validated in settings that reflect the complex host–parasite interactions that occur in open farming systems. 相似文献
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8.
Markis Adames Manuel Fernández-Ruvalcaba Guadalupe Pe?a-Chora Victor M. Hernández-Velázquez 《Journal of insect science (Online)》2011,11(1)
The aim of this work was to assess the virulence of strain M379 of the fungus,
Metarhizium anisopliae (Metchnikoff) Sorokin (Hypocreales:
Clavicipitaceae) after different passages through a suitable host and at different
concentrations for the control of both acaricide-susceptible and resistant strains of
the tick, Rhipicephalus (formerly Boophilus)
microplus Canestrini (Ixodida: Ixodidae) in vitro. The
highest value of LC50 for the susceptible strain corresponded to zero
passage with 7.68 × 107 conidia/ml followed by the fourth passage
with 2.68 × 107, which reduced 2.87-fold the lethal concentration.
When comparing LC50 values of the fourth vs. the seventh passage (2.59 ×
105 conidia/ml), the lethal concentration was reduced 103.47-fold by
the seventh passage. In addition, in the resistant strain the LC50 highest
value corresponded to zero passage with 4.95 × 107 conidia/ml
followed by the fourth passage with 7.86 × 106, which reduced
6.30-fold the lethal concentration. When comparing LC50 values of the
fourth vs. the seventh passage (1.04 × 105 conidia/ml) in the
resistant strain, the lethal concentration was reduced 75.58-fold by the seventh
passage. These results suggest that the number of passages on M.
anisopliae through a suitable host increased its virulence on both
R microplus strains. When comparing LC50 of the zero
passage through a suitable host of both acaricide-susceptible and resistant strains,
the highest LC50 values corresponded to the susceptible strain with 7.68
× 107 conidia/ml followed by the resistant one with 4.95 ×
107, showing that on the resistant strain the lethal concentration is
reduced by 1.55-fold. When comparing the fourth passage, the highest values of
LC50 corresponded to the susceptible strain with 2.68 ×
107 conidia/ml followed by the resistant one with 7.86 ×
106 conidia/ml, showing for the resistant strain a 3.41-fold reduced
lethal concentration. Moreover, when comparing the seventh passages, the highest
values of LC50 corresponded to the susceptible strain with 2.59 ×
105 followed by the resistant with 1.04 × 105
conidia/ml, revealing for the resistant strain a 2.49-fold reduced lethal
concentration. These results suggest that the resistant strain needs a lower
concentration of conidia than the susceptible strain. In this case, the
acaricide-resistant strain is more susceptible to M. anisopliae of
zero- and seven-passage strains. 相似文献
9.
Amoebic gill disease (AGD) is a proliferative gill tissue response caused by Neoparamoeba perurans and is the main disease affecting Australian marine farmed Atlantic salmon. We have previously proposed that macroscopic gill health ('gill score') trajectories and challenge survival provide evidence of a change in the nature of resistance to AGD. In order to examine whether the apparent development of resistance was because of an adaptive response, serum was sequentially sampled from the same individuals over the first three rounds of natural AGD infection and from survivors of a subsequent non-intervention AGD survival challenge. The systemic immune reaction to 'wildtype' Neoparamoeba sp. was characterized by Western blot analysis and differentiated to putative carbohydrate or peptide epitopes by periodate oxidation reactions. The proportion of seropositive fish increased from 46% to 77% with each AGD round. Antibody response to carbohydrate epitope(s) was immunodominant, occurring in 43–64% of samples. Antibodies that bound peptide epitope were identified in 16% of the challenge survivors. A 1:50 (single-dilution) enzyme-linked immunosorbent assay confirmed a measurable immune titre in 13% of the survivors. There was no evidence that antibodies recognizing wildtype Neoparamoeba provided significant protection against AGD. 相似文献
10.
