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941.
A summary and analysis have been carried out on data from over 6000 instances of flystrike in sheep in NZ, over a 16-year period, using a self-referral system where farmers submitted larvae and related information. The study covered a period of establishment and subsequent countrywide spread of the exotic blowfly, Lucilia cuprina. Comparisons are drawn between flystrike as it was perceived by surveys carried out before the 1940s, and the current situation with L. cuprina as an added major impediment. Briefly, the main differences are an increase in the prevalence of flystrike, changes in the representation and relative influence of individual primary blowfly species, an extension of the flystrike 'season', and an apparent increase in the importance of footrot as a factor predisposing to flystrike. Otherwise, flystrike is still primarily a disease of ewe lambs that are struck predominantly around the tail and perineum, mainly because of faecal staining. 相似文献
942.
Werners AH Bull S Vendrig JC Smyth T Bosch RR Fink-Gremmels J Bryant CE 《Veterinary immunology and immunopathology》2006,111(3-4):165-173
The inter- and intra-species differences in the response to lipopolysaccharides (LPS) are well recognised in mammalian species. It has been hypothesized that these differences can be attributed to genetic polymorphisms in the components involved in LPS signal transduction. These components include the cluster of differentiation factor 14 (CD-14), a membrane bound protein on the surface of mononuclear cells that recognises LPS and a receptor complex consisting of Toll-like receptor-4 (TLR-4) and myeloid differentiation factor-2 (MD-2). Sequencing of these three proteins in humans and mice revealed that all three are susceptible to polymorphic alterations, influencing the response to LPS. Previous experiments in the horse showed large inter-individual variations in the response to LPS. With the aim to assess this inter-individual variation, we performed a whole blood assay in 10 healthy horses as a functional assay to study the responsiveness to LPS. In 3 out of the 10 horses, LPS-induced TNF-alpha production was significantly lower compared to the overall mean. Subsequently the entire cDNA sequence encoding for the TLR-4, MD-2 and CD-14 protein was documented for each horse. Although mutations were observed in the sequence of TLR-4, these could not be related to an altered response to LPS in the concentration used in this study, as determined in the whole blood assay. Despite the various mutations found in the TLR-4 receptor protein, no alterations could be found in either the MD-2 or CD-14 gene, which are obviously more conserved structures. 相似文献
943.
Globoid cell leukodystrophy (GLD), or Krabbe's disease, is a progressive autosomal recessive disorder of the central nervous system in man and in various other species. GLD has been shown to result from various mutations in the gene encoding galactocerebrosidase (GALC), a lysosomal enzyme. We investigated the molecular basis of GLD in a related group of Irish setters. Sequencing of the GALC cDNA from an affected individual revealed an insertion mutation of 78 base pairs (bp) consisting of 16 bp of insertion site duplication and 62 bp of sequence derived from the U4 small nuclear RNA. We implemented a PCR-based test which is useful for identifying carriers of the mutation. 相似文献
944.
Bloom CA Labato MA Hazarika S Court MH 《Journal of veterinary pharmacology and therapeutics》2012,35(3):224-230
Fenoldopam is a selective dopamine-1 receptor agonist that causes peripheral arterial vasodilation, increased renal blood flow, and diuresis. Enthusiasm exists for the use of fenoldopam in nonpolyuric kidney injury in dogs, although pharmacokinetic data are lacking. The purpose of this study was to collect basic pharmacokinetic and hemodynamic effect data for fenoldopam when administered to healthy awake dogs. Six healthy, awake beagles were given a 180-min fenoldopam constant rate infusion at 0.8 μg/kg per minute followed by a 120-min washout period. Citrated blood was collected during and after infusion for the measurement of plasma fenoldopam concentration by HPLC with mass spectrometry. Heart rate and indirect systolic blood pressure were concurrently measured. Mean ± SD, steady-state plasma fenoldopam concentrations of 20 ± 17 ng/mL were achieved within 10 min of starting the infusion. Area under the plasma concentration-time curve was 3678 ± 3030 ng/mL · min, and plasma clearance was 66 ± 43 mL/min per kg. Elimination was rapidly achieved in all dogs. Heart rate and systolic blood pressure were unaffected by the fenoldopam infusion. Based on the results of this study, further evaluation of the effects of fenoldopam in dogs at differing doses and in dogs with clinical conditions such as acute nonpolyuric kidney injury is warranted. 相似文献
945.
946.
JD Mawyer CA Cavinder MM Vogelsang DH Sigler CC Love SP Brinsko TL Blanchard DD Varner CE Arnold S Teague RK Gordon 《Journal of animal science》2012,90(8):2532-2539
Stallions (n = 8) were implanted with a thermal sensory device in the muscle of the neck and the subcutaneous tissue of the scrotum and then assigned to either a nonexercise (Non-EX; n = 4) or exercise (EX; n = 4) group. A motorized equine exerciser was used to work EX stallions 30 min/d for 4 d/wk during a 12-wk period from July through October 2010. Temperatures (subcutaneous scrotal, intramuscular neck, and rectal) were recorded at 0, 22, and 30 min after the start of exercise, as well as 60 and 120 min post-exercise. Hourly ambient temperature and relative humidity data were also obtained. Semen was collected at 0, 4, 8, and 12 wk and analyzed for volume, sperm concentration, total sperm numbers, percentages of total and progressively motile sperm, sperm morphologic characteristics, and sperm DNA quality. No effect (P > 0.05) of exercise was observed on any of the measured semen variables. Implantation of thermal sensory devices had no demonstrable acute or chronic effects on the scrotal or neck tissue, indicating that the thermal sensory devices are a safe and effective way to measure subcutaneous scrotal and neck temperatures. At 22 and 30 min of exercise, rectal and neck temperatures increased (P < 0.0001) approximately 1.9 and 2.4°C, respectively, and scrotal temperatures simultaneously increased, although not significantly (P = 0.33), approximately 0.8°C. Correlations existed between scrotal, neck, rectal, and ambient temperatures, with the correlation between scrotal and rectal temperatures being greatest (r(s) = 0.76; P < 0.0001). Although moderate exercise for a short duration in extreme heat and humidity did significantly increase core body temperatures in stallions, scrotal temperatures did not significantly increase, and sperm parameters were unaffected. 相似文献
947.
A Pernthaner SJ Stasiuk JM Roberts IA Sutherland 《Veterinary immunology and immunopathology》2012,148(3-4):284-292
The glycolipid CarLA (carbohydrate larval antigen) is present on the epicuticle of the infective-stage larvae of gastrointestinal nematode parasites infecting livestock. The molecule is lost from the surface of the larvae in the few days post-ingestion by a host animal, and the resulting anti-CarLA antibody response has been demonstrated to be protective in vivo. Both the anti-CarLA response, and anti-parasite immunity in general, are slow to develop, and several months of natural exposure to ingested larvae is required. The current study was designed to provide information on how the anti-CarLA response develops, and focuses on the initial recognition of the molecule by human monocyte derived dendritic cells (mdDC) in vitro. Immunofluorescence and flow cytometry demonstrated that mdDC recognise and internalise both the purified and the native form of CarLA, in the case of the latter once it is shed from the larval surface. However, the recognition of CarLA did not result in classical maturation of DC, while there was only transient or minor up-regulation of CD86, CD83, HLA-DR and CD40. Exposure of mdDC to purified CarLA resulted in the increased production of the pro-inflammatory cytokines IL-6 and to a lesser extent of IL-8 and TNF-α, and a reduced production of the anti-inflammatory cytokine IL-1RA. CarLA therefore has little ability to mature and functionally alter monocyte derived dendritic cell function. 相似文献
948.
949.
Richard A.Murphy 《国外畜牧学(猪与禽)》2012,32(4)
过去的二十多年里,有机矿物质已作为微量矿物质的部分替代品使用,用以提高家禽某些方面的生产性能,如种鸡受精率、蛋壳强度及胴体和肉品质量.但是,当前研究发现:用更低水平但更易吸收的OTMs替代无机微量元素,可以最大限度减少矿物质排泄量并使与矿物质相关的生长性能性状最优化,这便给了我们更大的想象空间. 相似文献
950.
Ogundiyi AI Bemji MN Adebambo OA Dipeolu MA Onagbesan OM James IJ Osinowo OA 《Tropical animal health and production》2012,44(6):1263-1269
This study was carried out to assess the prevalence of mange in sheep and goats in five local government areas (LGAs) of Ogun State in South Western Nigeria. A total of 4,973 sheep and 7,902 goats of West African Dwarf breeds were sampled of which only 4 (0.08%) of sheep and 42 (0.53%) of goats were confirmed positive for mange infestation. In all the LGAs sampled, Odeda LGA had the highest concentration of sheep (39%) and goats (51%) while Abeokuta South had the least percentage of sheep (1%) and goats (1%). All the mange-infested cases in sheep were recorded in just one LGA (Ewekoro) which constituted 0.24% of the population within the location. For goats, three out of five LGAs namely: Obafemi Owode, Ewekoro and Abeokuta North had prevalence of 1.46%, 0.53% and 0.72% respectively. There was no significant (P > 0.05) difference between non-infested and infested animals in terms of packed cell volume (31.79 ± 0.87% vs. 31.41 ± 1.13%), haemoglobin (10.51 ± 0.21 g/100 ml vs. 10.28 ± 0.37 g/100 ml) and red blood cells (8.71 ± 0.29 × 10(12)/l vs. 9.40 ± 0.37 × 10(12)/l). The infested group however showed significantly (P < 0.01) higher white blood cells count (7.60 ± 0.22 × 10(9)/l) than the non-infested animals (6.81 ± 0.17 × 10(9)/l). Neutrophil, eosinophil, basophil and monocyte as well as chloride were not significantly affected by the health status of the animals. There existed significant (P < 0.01) difference between non-infested and infested animals in terms of total protein (5.42 ± 0.16 vs. 4.75 ± 0.20 g/dl), sodium (137.98 ± 1.53 vs. 128.92 ± 1.92 mEq/l) and potassium (4.04 ± 0.14 vs. 3.46 ± 0.18 mEq/l). It can be concluded from this study that the prevalence of mange mite infestation varied with location and was generally low or absent in some of the LGAs considered. Goats were particularly more susceptible to mange infestation than sheep. More concerted effort is needed to control mange in order to avoid spread since it is a contagious disease. 相似文献