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181.
Keegan KG Messer NT Reed SK Wilson DA Kramer J 《American journal of veterinary research》2008,69(2):167-173
OBJECTIVE: To determine the effectiveness of administering multiple doses of phenylbutazone alone or a combination of phenylbutazone and flunixin meglumine to alleviate lameness in horses. ANIMALS: 29 adult horses with naturally occurring forelimb and hind limb lameness. PROCEDURES: Lameness evaluations were performed by use of kinematic evaluation while horses were trotting on a treadmill. Lameness evaluations were performed before and 12 hours after administration of 2 nonsteroidal anti-inflammatory drug (NSAID) treatment regimens. Phenylbutazone paste was administered at approximately 2.2 mg/kg, PO, every 12 hours for 5 days, or phenylbutazone paste was administered at approximately 2.2 mg/kg, PO, every 12 hours for 5 days in combination with flunixin meglumine administered at 1.1 mg/kg, IV, every 12 hours for 5 days. RESULTS: Alleviation of lameness was greater after administration of the combination of NSAIDs than after oral administration of phenylbutazone alone. Improvement in horses after a combination of NSAIDs did not completely mask lameness. Five horses did not improve after either NSAID treatment regimen. All posttreatment plasma concentrations of NSAIDs were less than those currently allowed by the United States Equestrian Federation Inc for a single NSAID. One horse administered the combination NSAID regimen died of acute necrotizing colitis during the study. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of a combination of NSAIDs at the dosages and intervals used in the study reported here alleviated the lameness condition more effectively than did oral administration of phenylbutazone alone. This may attract use of combinations of NSAIDs to increase performance despite potential toxic adverse effects. 相似文献
182.
Reed SD 《Journal of the American Veterinary Medical Association》2008,232(2):194; author reply 194
183.
Anatomical properties of the ringed seal (Phoca hispida) heart and associated blood vessels reveal adaptations related to requirements for diving. Seven adult ringed seals were embalmed and dissected to document the gross anatomical features of the heart. Computed tomography images of the thoracic cavity were taken on one seal prior to dissection. The shape and position of the heart is different from the typical carnivore heart. The most notable difference is its dorsoventral flattened appearance with its right and left sides positioned, respectively, within the thoracic cavity. The long axis of the heart is positioned horizontally, parallel to the sternum. The right ventricle is spacious with thin walls which extend caudally to the apex of the heart such that the apex is comprised of both right and left ventricles. The cusps of the left atrioventricular valve of the ringed seal heart resemble an uninterrupted, circular curtain making it challenging to distinguish the divisions into parietal and septal cusps. 相似文献
184.
Neville TL Ward MA Reed JJ Soto-Navarro SA Julius SL Borowicz PP Taylor JB Redmer DA Reynolds LP Caton JS 《Journal of animal science》2008,86(4):890-901
Pregnant Targhee ewe lambs (n = 32; BW = 45.6 +/- 2.2 kg) were allotted randomly to 1 of 4 treatments in a completely randomized design to examine the effects of level and source of dietary Se on maternal and fetal visceral organ mass, cellularity estimates, and maternal jejunal crypt cell proliferation and vascularity. Diets contained (DM basis) either no added Se (control) or supranutritional Se from high-Se wheat at 3.0 ppm Se (SW) or from sodium selenate at 3 (S3) or 15 (S15) ppm Se. Diets were similar in CP (15.5%) and ME (2.68 Mcal/kg of DM) and were fed to meet or exceed requirements. Treatments were initiated at 50 +/- 5 d of gestation. The control, SW, S3, and S15 treatment diets provided 2.5, 75, 75, and 375 microg of Se/kg of BW, respectively. On d 134 +/- 10 of gestation, ewes were necropsied, and tissues were harvested. Contrasts, including control vs. Se treatments (SW, S3, and S15), SW vs. S3, and S3 vs. S15, were used to evaluate differences among Se levels and sources. There were no differences in ewe initial and final BW. Full viscera and liver mass (g/kg of empty BW and g/kg of maternal BW) and maternal liver protein concentration (mg/g) and content (g) were greater (P < 0.04) in Se-treated compared with control ewes. Maternal liver protein concentration was greater (P = 0.01) in SW vs. S3 ewes, and content was greater (P = 0.01) in S15 compared with S3 ewes. Maternal jejunal mucosal DNA concentration (mg/g) was greater (P = 0.08) in SW compared with S3 ewes. Total number of proliferating cells in maternal jejunal mucosa was greater (P = 0.02) in Se-fed compared with control ewes. Capillary number density within maternal jejunal tissue was greater (P = 0.08) in S3 compared with SW ewes. Selenium treatment resulted in reduced fetal heart girth (P = 0.08). Fetal kidney RNA (P = 0.04) and protein concentrations (mg/g; P = 0.03) were greater in Se-treated compared with control ewes. These results indicate that supranutritional dietary Se increases cell numbers in maternal jejunal mucosa through increased crypt cell proliferation. No indications of toxicity were observed in any of the Se treatments. 相似文献
185.
Current strains of fowlpox virus (FWPV) carrying circulating reticuloendotheliosis virus (FWPV-REV) sequence are becoming more pathogenic to poultry. This is evidenced by the fact that vaccination with current available FWPV vaccines provides limited protection against them. To characterize REV insertions in a collection of both older and more recent field isolates, we developed three different types of adjacent oligoprobes and primer sets from specific genomic locations of FWPV and REV: REV-ENV (accession no. K02537, 1382-2260), FWPV-REV integration site (accession no. AF006064, 86-1328), FWPV (accession no. AF198100, 232461-232670), and REV-LTR (accession no. V01204, 305-496). The data indicated that the primers from the REV-ENV region and the TaqMan probes specifically targeted REV-ENV sequences of FWPV-REV strains. Furthermore, the strains were differentiated based on quantitative melting temperature (T(m)) of their amplified products using FRET-based probes. The amplified products were further characterized by sequencing and multiple sequence alignment analysis. The results suggest that integrated REV-ENV sequences are both common and mostly conserved in field isolates. However, the minor variations found within the short-targeted ENV sequence from FWPV-REV strains suggest that these strains could have either undergone periodic point mutational changes or integration with different REV-ENV subtypes. 相似文献
186.
DJ Leatherman SA Valdez BG Grant JC Cannon 《Journal of Equine Veterinary Science》1999,19(12):776, 778
Protein fractions of cerebral spinal fluid samples were analyzed in an effort to find a reliable, minimally invasive and cost effective method of diagnosing cervical vertebral myelopathy. There were six separate protein fractions analyzed by electrophoresis. In this study we specifically looked for a post beta spike in horses with spinal cord compression. There was no correlation in our study between horses with a post beta spike and CVM as diagnosed by a myelogram. 相似文献
187.
Access to the Internet is an essential determinant of innovation, which has received little attention in the literature. This paper emphasizes the role of Internet accessibility in lowering information costs and therefore boosting regional innovation activity. We construct a simple theoretical model to illustrate the positive impact of decreased discovery costs, proxied by the accessibility of the Internet, on innovation. To test this hypothesis, we exploit a county‐level data set in the U.S. and run three types of regression with and without instruments: OLS, negative binomial, and Poisson. Within each method, we employ four levels of download speeds. We find a positive relationship between the access to the Internet and the number of patents filed in that specific county. This effect is particularly strong in the case of access to download speeds of 10 Mbps. Our analysis suggests that access to the Internet lowers information disseminating costs and therefore encourages more patents filed in the county. The results also indicate that access to the Internet matters more than faster Internet speed for innovation. Policy implications for these results suggest that if there were a minimum Internet access initiative, there could potentially be a significant increase in innovation by the U.S. 相似文献
188.
- 1. Closure of the Taff/Ely Estuary by the Cardiff Bay barrage in 1999 resulted in the replacement of intertidal mudflats by a permanent freshwater lake. This led to an 89% reduction in the population of shelducks Tadorna tadorna.
- 2. The birds switched from foraging mainly for Nereis diversicolor and Hydrobia ulvae by scything with the bill as they walked across the mudflats at low tide, to feeding on benthic chironomid midge larvae while swimming in shallow water around the margins of the lake.
- 3. The population decline occurred as a consequence of a decrease in the area available for foraging — from about 1 km2 of mudflats to about 0.1 km2 of water shallow enough for shelducks to reach the bottom when dabbling, head dipping and upending.
- 4. Contrary to expectation, the amount of time shelducks spent feeding was similar pre‐ and post‐barrage, and their body and plumage condition improved.
- 5. A tidal rhythm in activity persisted, with a reduced amount of feeding at high tide, probably because of the slight rise in water levels that sometimes occurred at this time.
189.
190.
SUMMARY An investigation of sheep flocks with unknown histories of fleece derangement, selected at random from the main sheep raising areas of New South Wales, showed that Psorergates ovis was present in 53 of the 177 flocks surveyed and In 162 of the 3495 sheep examined. Of the single causes of fleece derangement, the most prevalent was grass seed contamination (15.7%) followed by Infestation with sheep body lice, Bovicola ovis, (14.7%) and Infestation with Itch mite (7.8%). The prevalence of fleece derangement was significantly higher on sheep In which lice were the only ectoparasites found than on those In which Itch mites were the only ectoparasites present. The greatest prevalence of P ovis was In flocks In the Young, Yass, Mudgee and Tenterfield districts. In most affected flocks, more than one potential cause of fleece derangement was present. Itch mite Infestation was more prevalent in flocks that received no treatment for ectoparasites than in those that had been treated in the year preceding the survey. Our results did not support a commonly held belief among farmers that arsenical compounds control Infestations of Itch mites more effectively than other types of pesticides. There was no significant difference in prevalence of fleece derangement between flocks treated with different pesticide groups and those that received no treatment, but mean fleece derangement score was significantly lower in sheep treated with organophosphates than in untreated sheep. Infestations of lice were significantly more prevalent in sheep from flocks treated with synthetic pyrethroids than from those treated with organophosphates or those that received no treatment. 相似文献