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Endoscopic and virological observations on respiratory disease in a group of young Thoroughbred horses in training 总被引:2,自引:0,他引:2
M H Burrell 《Equine veterinary journal》1985,17(2):99-103
A group of racehorses in training was examined on several occasions with a fibreoptic endoscope and monitored for viral infection. Only equine herpes virus-2 (EHV-2) infection was detected. Pharyngeal lymphoid hyperplasia (PLH) was present in all horses and decreased in severity with age. There was no association between PLH severity and antibody titres to EHV-1, or with the isolation of EHV-2. Finishing position in races was not affected by PLH severity. Exercise induced pulmonary haemorrhage (EIPH) was evident on 23 out of 49 (47 per cent) examinations after maximal speed training exercise. Eighteen out of 19 (95 per cent) horses examined on at least two occasions had EIPH but its occurrence was not predictable. Observable mucoid or mucopurulent exudate was present in the trachea in 60 out of 118 (50 per cent) examinations and the amount seen was increased following exercise. 相似文献
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Caitlin Lark Widener William M. Graves Kayla J. Alward Jillian F. Bohlen 《Reproduction in domestic animals》2019,54(11):1470-1476
The objective of this study was to examine the impact of a bovine respiratory disease complex (BRDC) vaccine with a temperature‐sensitive modified live vaccine (MLV) infectious bovine rhinotracheitis (IBR) component on oestrous cycle parameters and the follicular pool. Twenty‐four Holstein heifers (12.4 ± 0.5 months) previously calfhood vaccinated with an IBR MLV component were enrolled in two replicates (Spring; n = 10 and Fall; n = 14) and were blocked by pre‐vaccination bovine viral diarrhoea (BVD) serum neutralizing (SN) titres. Upon enrolment, heifers were oestrous synchronized with sampling beginning at detected oestrus. At their second heat, heifers were vaccinated with a BRDC calfhood vaccine with a MLV (MLV; n = 12) or killed (K; n = 12) IBR component and sampled for two additional cycles. Serum samples for oestrogen (E2) and progesterone (P4) as well as ultrasound data of ovarian structures were collected every other day. Serum samples for anti‐Müllerian hormone (AMH) were collected at oestrus and mid‐cycle for each cycle, and serum for titres was collected prior to and following vaccination. Data were analysed with the PROC MIXED and GLM procedures of SAS. There was no difference in pre‐ or post‐vaccination titres between MLV and K heifers (p > .5). Vaccination had no impact on P4 concentrations, P4 area under the curve, luteal tissue area, peak E2 production or oestrous cycle length (p > .05). Cycle number did impact AMH concentration (p < .05). In MLV heifers, AMH concentration was highest in cycle 1 (p < .05) while cycles 2 and 3 did not differ (p > .05). This was also true for the K heifers in the Fall replicate (p < .05). Within cycle 2, AMH concentrations were numerically lower between vaccine types (K = 308.22 ± 33.3 pg/ml, MLV = 181.13 ± 32.9 pg/ml; p > .05). Although no differences were seen in overall cycle parameters, differences in AMH concentrations may indicate a reduction of the follicular pool following vaccination and requires further investigation. 相似文献
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OBJECTIVE: To determine the effect of acute (clinical history of glaucoma for 相似文献
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Caitlin C. Rothacker Ashley G. Boyle David G. Levine 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(7):709-714
The purpose of this retrospective case series was to assess the outcome of an autologous vaccination procedure on single and multiple sarcoid lesions, determine complication rate, and report owner satisfaction. Medical records (18 cases) from January 2009 through May 2014 were evaluated to identify horses undergoing the procedure. Signalment, number, size, anatomic location of lesions, and type of historical treatment were recorded. Follow-up was obtained via standardized owner survey, veterinary examination, and digital images. Data recorded and analyzed included ancillary therapies post-procedure, decrease in number and/or size of sarcoid lesions, sarcoid regrowth, complications, and owner satisfaction. There was a decrease in number of lesions observed by owners in 75% of cases and a decrease in size of sarcoids in 93.8% of cases. Clinical regression observed by owners was noted in 68.8% of cases. There were complications in 43.8% of cases and owner satisfaction in 75% of cases. 相似文献
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Studies show that retrieval practices such as homework assignments that are completed during the encoding phase of learning benefit knowledge acquisition and retention. In addition, desirable difficulties, which are strategies that intentionally create a greater challenge during initial learning to enhance encoding and retrieval pathways, also benefit learning long term. Our objective was to determine whether weekly homework questions intended to create desirable difficulties by requiring higher-order cognitive skills (HOCS) benefited students’ long-term retention of physiology concepts compared to questions designed to require lower-order cognitive skills (LOCS). Undergraduate students in a junior-level animal physiology course were presented information during weekly laboratory periods, and then required to complete retrieval practices in the form of online homework assignments 5 d after each lab. Homework questions were formatted per Bloom’s Taxonomy to require HOCS (i.e., level 4 or 5) or LOCS (i.e., level 1 or 2). Information retention was assessed the next week via performance on an in-class quiz and again at semesters’ end via performance on a final practical exam. We observed no differences in performance on the in-class quiz or final practical exam between students randomly assigned to complete homework with HOCS questions compared to LOCS questions. However, students that received homework with HOCS questions had decreased (P < 0.05) performance scores on 9 out of the 11 homework assignments compared to those receiving homework with LOCS questions. These findings indicate that desirable difficulties were not created by our HOCS homework questions because students receiving these more difficult retrieval practices did not achieve equal success on them. As a result, this attempt to create variations in cognitive demand did not enhance retention of knowledge in this study. 相似文献
70.
Jane Kilcoyne Stephen Burrell Cíara Nulty Rafael Salas Elliott J. Wright Isabelle Rajotte Christopher O. Miles 《Marine drugs》2020,18(12)
Okadaic acid (OA) group toxins may accumulate in shellfish and can result in diarrhetic shellfish poisoning when consumed by humans, and are therefore regulated. Purified toxins are required for the production of certified reference materials used to accurately quantitate toxin levels in shellfish and water samples, and for other research purposes. An improved procedure was developed for the isolation of dinophysistoxin 2 (DTX2) from shellfish (M. edulis), reducing the number of purification steps from eight to five, thereby increasing recoveries to ~68%, compared to ~40% in a previously reported method, and a purity of >95%. Cell densities and toxin production were monitored in cultures of Prorocentrum lima, that produced OA, DTX1, and their esters, over ~1.5 years with maximum cell densities of ~70,000 cells mL−1 observed. Toxin accumulation progressively increased over the study period, to ~0.7 and 2.1 mg L−1 of OA and DTX1 (including their esters), respectively, providing information on appropriate harvesting times. A procedure for the purification of OA and DTX1 from the harvested biomass was developed employing four purification steps, with recoveries of ~76% and purities of >95% being achieved. Purities were confirmed by LC-HRMS, LC-UV, and NMR spectroscopy. Additional stability observations led to a better understanding of the chemistry of these toxins. 相似文献