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71.
Antiparasitic efficacy of ivermectin against migrating Gasterophilus intestinalis was evaluated in 36 treated and 24 nontreated (n = 12) or vehicle-treated (n = 12) ponies experimentally and naturally infected with G intestinalis and naturally infected with G nasalis. Each pony was experimentally infected with 500 G intestinalis 1st instars in 2 divided doses on days -14 and -7 before treatment. On day 0, ivermectin was administered at the rate of 200 micrograms/kg of body weight by IV (n = 12) or IM injection (n = 12) or given as an oral paste (n = 12). Ponies were euthanatized and necropsied 21 days after treatment. In each nontreated or vehicle-treated pony, late 1st-, 1st- to 2nd- instar molt, and early 2nd-instars of G intestinalis were found in the mouth, and 2nd- and 3rd instars of G intestinalis and 3rd instars of G nasalis were found in the stomach. Bots were not found in any ivermectin-treated pony and, thus, ivermectin was 100% effective against oral and gastric stages. Adverse reactions were not observed in ponies given ivermectin by IM injection or orally, but 1 pony given the vehicle IV and 1 pony given ivermectin (in the vehicle) IV had an anaphylactic reaction, resulting in death of the ivermectin-treated pony. It was speculated that the adverse reaction was caused by histamines released in response to vehicle components given by IV injection.  相似文献   
72.
MicroLactin is a patented milk protein concentrate whose mode of action is proposed to inhibit neutrophil activation in inflammation and to bolster the immune response in musculoskeletal diseases. MicroLactin was empirically used in the treatment of a series of equine clinical cases. MicroLactin was given in two trials to 166 horses in which neutrophils were associated with an inflammatory response. The primary clinical groups having the greatest positive responders to the use of MicroLactin were: respiratory (92%), joint lameness/foot trauma (90%), muscle injury/myositis (92%), equine protozoal myeloencephalitis (EPM) (81%), skin trauma/hypersensitivity (89%), and toxic enteritis (89%). Positive clinical results were seen within 10 to 14 days when MicroLactin was used as a daily treatment either alone or in combination with other anti-inflammatory agents or as an adjunct to the primary treatment.  相似文献   
73.
Comprehensive and standardized biodiversity monitoring schemes are needed to build scientifically sound decision-making tools for biodiversity conservation. Based on a thorough review of published literature, we propose a novel biodiversity monitoring framework to unify conservation theory and practice. The framework is built on the inter-connection among different types of indicators, and on the systematic articulation of their relationships into seven indicator approaches. Semi-natural grasslands and shrublands in Europe, which still lack a common biodiversity monitoring scheme, are used as a model for the framework. Different biotic indicators have been widely used to estimate the state of biodiversity, but we integrate these with biodiversity drivers, i.e. factors driving changes in biodiversity, to track biodiversity response to environmental changes. Precise information on biodiversity drivers (e.g. past and present management or disturbance regimes, environmental conditions, landscape patterns) has an effective indicator value, but this is often not taken into account in monitoring schemes. Our framework can be used to detect gaps in available data, translate indicator systems into practical conservation, identify combined sets of indicators to monitor biodiversity in target habitats, and recognize most suitable surrogates when information for some indicators is missing. We also take into account the effect of regional species pools in order to consider large-scale historical and biogeographical processes. We propose general guidelines to create validate and launch biodiversity monitoring frameworks for target habitats in the light of current examples of biodiversity conservation schemes (e.g. Natura 2000 in Europe).  相似文献   
74.
O. Leblanc    M. Dueñas    M. Hernández    S. Bello    V. Garcia    J. Berthaud  Y. Savidan 《Plant Breeding》1995,114(3):226-230
A collection of embryogenic diploid calli of Tripsacum was established and treated with colchicine to induce chromosome doubling. Sections containing duplicated cells in calli were identified using flow cytometry and ploidy level was determined in the regenerated plantlets. Tetraploid plants from several origins were obtained. In contrast to wild polyploid plants, which show apomictic development, the regenerated tetraploid plants reproduced sexually. By hybridizing these plants with wild tetraploid apomicts, various populations were established; these will allow a study of the inheritance of apomixis in Tripsacum.  相似文献   
75.
A liquid chromatographic method for the assay of morphine sulfate and some preservatives and impurities in the bulk drug and in injections has been developed and collaboratively studied in 8 laboratories. Each collaborator analyzed 5 samples: 1 bulk drug, 3 different concentrations of injectable dosages, and 1 prepared mixture containing, in addition to morphine sulfate, phenol, 2-mercaptobenzothiazole, and pseudomorphine. The proposed method quantitates morphine sulfate and resolves the other components for identification using a C18 reverse-phase column with a mobile solvent containing 240 mL methanol, 720 mL 0.005 M 1-heptanesulfonic acid Na salt, and 10 mL acetic acid. Samples are prepared by direct dilution with mobile solvent minus 1-heptanesulfonic acid. All collaborators met system suitability requirements and performed the analysis without difficulty. No outliers were found when data were analyzed by the Dixon, Grubbs, double Grubbs, and Cochran tests. Relative standard deviations between laboratories (RSDR) for duplicate determinations of morphine sulfate ranged from 1.4 to 2.1%. Mean morphine sulfate recoveries for the bulk drug and the prepared mixture were 100.8 and 100.4%, respectively. The method has been approved interim official first action.  相似文献   
76.
We studied the nematofauna in cultivated Euvisols in the Spanish Central Region in terms of multivariate statistical relationships between nematode groups and environmental variables (habitat, hosts, soil lexture, and quantitative edaphic variables). Three large nematode associations were recognized, one group being characteristic of the region's rotational crops (Pratylenchus, Ditylenchus, Helicotylenchus, Tylenchorhynchus, Rotylenchus, other Dorylaimidae,Plectus, andTylenchus), a second group related to cereal monoculture and wild gramineae associated with bush formations (Heterodera, Criconemoides, Discolaimus, and other Rhabditidae), and a third group characteristic of uncultivated soils (Paratylenchus, Xiphinema, Hemicycliophora, Mononchus, Tripyla, andAlaimus).Paratylenchus andTylenchus species were shown to have an indicator value for certain edaphic properties, especially soil texture, and may be regulated by the clay content of the soil.  相似文献   
77.
78.
Nitrogen inputs, outputs and compartamentalization were quantified in a freshwater fish pond stocked with hybrid Oreochromis throughout a production cycle. The budget accounts for 91% of the nitrogen added to the system. Feed addition accounted for 87% of the nitrogen input and an additional 11% was attributable to nitrogen fixation, mainly in the water column. The balance of the nitrogen input was contained in the source water for the pond. Commercial-size fish accumulated 17.5% of the nitrogen added to the system. Most of the nitrogen was eventually deposited in the sediments. Nitrification constituted a major pathway for nitrogen transformation, but only 1% of the nitrogen input was lost through denitrification.  相似文献   
79.
The effects of different stressors on the atretic degeneration of ovarian vitellogenic follicles, as well as on the ovarian mass, were examined in female Atlantic bluefin tuna, Thunnus thynnus (L.), from the Mediterranean Sea. The stressors taken into consideration were short-term starvation (up to 14 days), long-term cage rearing (1 year) and crowding-induced severe panic frenzy. Wild-caught individuals were used as a control group. Fish subjected to either severe panic frenzy or starvation exhibited a decrease in gonad mass and had significantly higher intensity of α atresia in the vitellogenic follicles (means: 78% and 58%, respectively; range: 36-100%) than either wild or long-term caged individuals (means: 32% and 30%, respectively; range: 19-44%). The extensive atresia in fish stressed by severe panic frenzy was observed as early as 24 h after the stressing event. The present study represents the first evidence of the extreme susceptibility of Atlantic bluefin tuna to severe acute stress during vitellogenesis; it also shows that starvation is associated with progressive reabsorption of vitellogenic oocytes.  相似文献   
80.
Abstract

Zaprionus indianus Gupta (Diptera: Drosophilidae) is a successful invasive drosophilid that is currently impacting fig production in Mexico and Brazil. Very few studies have examined the improvement of trapping strategies for this pest. Here, we compared visual responses of Z. indianus to different colors and olfactory cues. Orange and brown colored traps were among the most attractive in choice and no-choice tests, with violet and white being the least attractive colors. Orange traps with brown circles around the access holes were more attractive than uniformly orange traps. Apple cider vinegar was significantly more attractive to adults than sugar cane vinegar or grape juice but was not significantly more attractive than white wine and red wine vinegars. Captures of Z. indianus in apple cider vinegar-baited traps were not improved by the addition of grape, pineapple or apple juices, or when compared against a sucrose solution or grape juice fermented with Saccharomyces cerevisiae, or grape juice fermented with Candida tropicalis. Pairwise comparisons of Z. indianus attraction to S. cerevisiae and C. tropicalis indicated a high dependence on the growth media used. Orange traps with brown circles baited with apple cider vinegar may prove useful for monitoring this pest under field conditions.  相似文献   
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