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171.
The risk of seabird bycatch in trawl fisheries is increased by high numbers of seabirds attending vessels to feed on fish waste discharged. We conducted an experimental test of whether mincing fish waste prior to its discharge from a factory trawler reduced the number of seabirds attending the vessel. The trial was conducted on a mid-water trawler targeting hoki (Macruronus novaezelandiae) in New Zealand waters, and the experiment compared three treatments (1) discharging ‘unprocessed’ waste (fish offal and whole discards), (2) mincing all waste to a small particle size before discharge, or, (3) converting all waste to fishmeal and reducing discharge to sump water. The response to the experimental treatments was determined using seabird abundance within a 40 m-radius semi-circular area centred on the vessel stern. Mincing reduced the numbers of large albatrosses (Diomedea spp.) feeding astern of the vessel, but had no significant effect on other groups of seabirds. In contrast, reducing discharge to sump water resulted in a significant reduction in numbers of all groups of seabirds. In particular, the abundance of the small albatross group (principally Thalassarche spp.), and some smaller procellarids (e.g. sooty shearwater, Puffinus griseus, and white-chinned petrel, Procellaria aequinoctialis), was reduced to less than five percent of the number that were within the sweep area when unprocessed discharge was released. While mincing significantly reduced the abundance of large albatrosses at the vessel stern, relatively small numbers of these birds attend trawl vessels in New Zealand waters and associated bycatch rates are low. In contrast, reducing the quantity of fish waste discharge by mealing resulted in reduced abundances of a wide range of seabirds at the vessel. Therefore, compared to mincing, we recommend fish waste retention as a more effective management strategy for reducing seabird bycatch.  相似文献   
172.
Ketamine is widely used in equine anaesthesia. Beside its anaesthetic and analgesic properties, ketamine possesses a cytokine-modulating activity. However, to date, no data are available regarding the inhibitory effect of ketamine on the cytokine response in horses. In horses, cytokines such as tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) play a pivotal role in the pathogenesis of equine endotoxaemia following gastrointestinal disorders. Hence, the objective of this study was to assess the influence of ketamine on LPS-induced TNF-alpha and IL-6 formation in an equine macrophage cell line (eCAS cells). The results demonstrate a cytokine-modulating activity of ketamine in an equine cell line, suggesting a beneficial role for ketamine in the treatment of equine endotoxaemia.  相似文献   
173.
OBJECTIVE: To evaluate cytokine production by equine alveolar macrophages after exposure to lipopolysaccharide (LPS), Aspergillus fumigatus, and hay dust, and determine the effect of clenbuterol on the cytokine response. ANIMALS: 6 horses. PROCEDURE: Alveolar macrophages were exposed to PBS solution (negative control), LPS, hyphae and conidia of Aspergillus fumigatus (AF), or a suspension of hay dust (HDS) and incubated for 24 hours at 37 degrees C. Concentrations of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta were measured in the supernatant. The procedure was repeated with cells that were concurrently incubated with 0.5 microM clenbuterol. RESULTS: Exposure to HDS and AF significantly increased production of TNF-alpha by equine alveolar macrophages. The increase in TNF-alpha produced in response to HDS and AF was 5 and 7 times as great, respectively, as the increase measured in response to LPS. The concentration of IL-1beta in the supernatant was significantly increased after exposure of cells to AF. Clenbuterol was effective at inhibiting TNF-alpha production by cells exposed to LPS, HDS, or AF. CONCLUSIONS AND CLINICAL RELEVANCE: Increased production of TNF-alpha and IL-1 indicated that the pro-inflammatory cytokines produced by alveolar macrophages in response to allergens may play a role in recurrent airway obstruction (RAO) in horses. Equine alveolar macrophages are not only a primary pulmonary defense mechanism but may also influence the pathogenesis of equine RAO. The beta2-adrenoceptor agonist clenbuterol, a drug that is commonly used for treatment of equine RAO, promotes immediate bronchodilation and may also contribute to downward modulation of the inflammatory response.  相似文献   
174.
OBJECTIVE: To design a treatment that increases plasma corticosteroid concentrations to mimic prenatal stress in pregnant sows. ANIMALS: 24 pregnant sows. PROCEDURE: Sows were assigned to 1 of 4 treatment groups; treatment consisted of twice-daily oral administration of a placebo or 20, 60, or 180 mg of hydrocortisone acetate (HCA)/sow from 7 to 11 weeks of gestation. Blood and saliva samples for determination of cortisol concentrations were obtained hourly on treatment days 3 and 25 and twice weekly for the remainder of the treatment period. The WBC, neutrophil, and lymphocyte counts and concentrations of interleukin (IL)-2 and IL-4 were determined on 4 days during treatment. Litter characteristics were recorded. RESULTS: Plasma and salivary cortisol concentrations were significantly increased in sows that received 60 or 180 mg of HCA (0.30 to 0.37 mg/kg and 0.95 to 1.15 mg/kg, respectively), compared with control sows. Except for the second day of treatment, the number of WBCs and the IL-2:IL-4 ratio did not differ among treatment groups. The neutrophil-to-lymphocyte ratio was significantly higher in sows that received 180 mg of HCA. Gestation duration was significantly shorter in sows that received 180 mg of HCA. CONCLUSIONS AND CLINICAL RELEVANCE: Oral administration of 60 mg of HCA is suitable to increase plasma and salivary cortisol concentrations in pregnant sows in a controlled manner to concentrations comparable to concentrations detected after psychologic stressors. This model seems to be suitable to study the effects of increased maternal corticosteroid concentrations on young pig behavior, physiologic variables, and development.  相似文献   
175.
OBJECTIVE: To determine whether treatment of horses with antitussive agents before bronchoalveolar lavage (BAL) reduces the frequency and intensity of the cough reflex during BAL. ANIMALS: 8 healthy horses. PROCEDURE: Standard BAL was performed on each horse weekly for 6 weeks. Detomidine was used as a general sedative, and various antitussive agents were evaluated for their suitability to suppress undesirable coughing. Treatments administered prior to BAL consisted of saline (0.9% NaCl) solution (control treatment), codeine, butorphanol tartrate, glycopyrrolate, lidocaine hydrochloride (final concentration, 0.33%), and lidocaine hydrochloride at a final concentration of 0.66% (lidocaine 0.66%). Frequency and intensity of coughing were digitally recorded throughout the BAL procedure. The volume of BAL fluid collected was measured, and the fluid was cytologically examined to assess potential effects of the medications on composition. RESULTS: Coughing frequency was significantly reduced after intratracheal administration of lidocaine 0.66%. Moreover, intratracheal administration of lidocaine 0.66% or IV administration of butorphanol resulted in a significant reduction in the intensity of coughing episodes. All other treatments failed to significantly suppress coughing frequency and intensity, compared with results for the saline treatment. Glycopyrrolate caused obvious adverse clinical effects. Treatments did not influence the volume of BAL fluid collected nor composition of the fluid. CONCLUSIONS AND CLINICAL RELEVANCE: Intratracheal administration of lidocaine (final concentration, 0.66%) proved to be the most reliable method to reduce frequency and intensity of coughing in horses during BAL.  相似文献   
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178.
There is an increasing effort to understand the many sources of population variability that can influence drug absorption, metabolism, disposition, and clearance in veterinary species. This growing interest reflects the recognition that this diversity can influence dose–exposure–response relationships and can affect the drug residues present in the edible tissues of food‐producing animals. To appreciate the pharmacokinetic diversity that may exist across a population of potential drug product recipients, both endogenous and exogenous variables need to be considered. The American Academy of Veterinary Pharmacology and Therapeutics hosted a 1‐day session during the 2017 Biennial meeting to explore the sources of population variability recognized to impact veterinary medicine. The following review highlights the information shared during that session. In Part I of this workshop report, we consider sources of population variability associated with drug metabolism and membrane transport. Part II of this report highlights the use of modeling and simulation to support an appreciation of the variability in dose–exposure–response relationships.  相似文献   
179.
Drawing on an analysis of in‐depth interviews with returned migrant women from East Nusa Tenggara, Indonesia, this paper considers the links between migration, religious beliefs and subjectivity. Low‐skilled migrant women, including domestic workers, have often been represented as marginalised. This paper argues that in the context of migration, women constantly move through trajectories of power using religion as a spiritual resource. Against the commonly patriarchal characteristics of their religion and community, the women employ cognitive strategies to face challenges in migration. In each stage of their transnational migration, the women's experiences reveal the multitude of ways in which they continue to invest in their beliefs through everyday practices, rituals and networking. These experiences highlight the women's strategies in accessing different forms of power. This study demonstrates the significance of focusing on these women's experiences, including their everyday religious practices and their shifting sense of self, as a way of broadening the conceptual basis of our understanding of female migration.  相似文献   
180.
Prunus virginiana L. (chokecherry) fruit has potential to provide both food and energy and as annual yield of biomass and energy are much greater than annual crops such as canola and wheat. We determined chokecherry fruit weight fractions as well as pit and extracted seed oil concentrations and fatty acid composition. Gross energy for each of the fractions was determined, as were carbon and nitrogen content. Extrapolation of these data suggests that gross energy from pits alone over a 24-year period (890 GJ·ha(-1)) is equivalent to that from an entire canola/wheat rotation (850 GJ·ha(-1)). After maturity, pulp contributes an additional 1130 GJ·ha(-1) over 21 years from ~3.4 t·ha(-1)·year(-1) (dw), while wood from pruning could add another 60 GJ·ha(-1)·year(-1). Over this time period, chokecherry would produce 1.5-2.5 times the amount of oil produced by a canola/wheat rotation.  相似文献   
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