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The objective was to compare embryo yield and quality in lactating dairy cows superovulated (SO) with varying amounts of gonadotropins and FSH:LH ratios and inseminated with SexedULTRA? sex‐sorted semen. The SO treatments (n = 77) involved 3 protocols: groups F700 and F1000 were given total doses of 700 and 1,000 IU of Folltropin (FSH:LH ratio 49:1), respectively, whereas group F700P300 was given 700 IU of Folltropin + 300 IU of Pluset (FSH:LH ratio 1:1). Cows were artificially inseminated 3 times over a 10‐hr interval with frozen‐thawed SexedULTRA? sex‐sorted semen (total of 10 × 106 sex‐sorted sperm), starting 18 hr after onset of oestrus, with embryos/ova recovered 7 d after oestrus. Total number of recovered structures and transferable embryos were lower (p < 0.05) in F700 (4.7 ± 3.0 and 1.9 ± 1.7, respectively; mean ± SD) compared to F1000 (8.1 ± 3.8 and 4.4 ± 2.6) and F700P300 (8.5 ± 6.4 and 4.5 ± 3.3). Percentage of cows ovulating >50% of follicles ≥0.8 cm in diameter was lower (p < 0.05) in F700 (35.5%) than in F1000 (82.4%) and F700P300 (73.1%). Percentage of unfertilized oocytes was higher (p < 0.05) in F700 (45.0% vs. 27.7% for F1000 and 29.0% for F700P300) whereas percentage of morulae was higher (p < 0.05) in F1000 (19.3% vs. 8.7% for F700 and 12.2% for F700P300). Embryo quality was similar among groups (p > 0.05). In conclusion, embryo production in lactating dairy cows was improved by increasing total dose of gonadotropins from 700 to 1,000 IU, with SexedULTRA? sex‐sorted semen yielding satisfactory fertilization rates and embryo quality.  相似文献   

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Contrast‐enhanced ultrasonography provides a more functional diagnostic image than conventional ultrasonography. This prospective exploratory study compared the novel contrast agent, Visphere?, with commercial contrast agents in five healthy Beagle dogs. Visphere? has the smallest diameter and highest concentration compared with Sonazoid® and SonoVue®. Each dog received an intravenous injection of Visphere?, Sonazoid®, or SonoVue®. Images were recorded for 300, 600, and 60 s in the heart, liver, and left kidney, respectively. The mean pixel values of the regions of interest for each organ were expressed as time intensity curves (TIC). The agents all improved the visualization of left ventricular endocardial border delineation in the heart, and had similar TICs and clinical useful durations. In contrast, Visphere? expressed the highest mean pixel value in the liver parenchyma at an early observation time and maintained the intensity until 600 s, like Sonazoid®. The renal evaluation results indicated there were no statistically significant differences in time‐to‐peak for the renal cortex or medulla among the agents. Compared with the other two agents, SonoVue® had the lowest peak enhancement for the renal cortex and medulla. No dogs had any adverse reactions during or after the study. All three agents provided adequate results for left ventricular endocardial border delineation, and Visphere? may have the same potential as Sonazoid® to detect and characterize hepatic lesions. Visphere? and Sonazoid® may offer better visualization quality to evaluate renal function. In conclusion, the novel contrast agent, Visphere?, is comparable with commercial agents and could be applied in different major organs in dogs.  相似文献   

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Seven of nine colostrum‐deprived calves, free from infection with bovine virus diarrhoea virus (BVDV), were vaccinated with Rispoval? RS‐BVD on two occasions, 21 days apart, while the other two were kept as BVDV infection controls. The virus neutralizing (VN) serum antibodies induced by vaccination were tested for their ability to neutralize 18 European BVDV isolates, including laboratory reference strains and recent field isolates, both cytopathic and non‐cytopathic biotypes as well as genotypes I and II. The strains were isolated in Belgium, France, Germany and the United Kingdom. While there were large variations in the vaccine‐induced VN titres of the individual calves against all the strains, e.g. the titres against Osloss NCP, the European reference strain ranged from 1.7 to 6.7 (1 : log2), serum from each animal was capable of neutralizing between nine and all 18 of the strains tested. Nevertheless, from the results of this study, it can be concluded that in colostrum‐deprived BVDV seronegative calves, Rispoval? RS‐BVD can stimulate the production of VN antibodies capable of neutralizing a wide range of antigenically diverse European isolates of BVDV, including genotypes I and II.  相似文献   

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This study was designed to evaluate the effect of single layer centrifugation (SLC) and subsequent cold storage on stallion sperm capacitation‐like status and acrosome reaction. Three stallions were included in the study, with three ejaculates per stallion. The samples were examined 4, 24 and 72 h after collection, extension and SLC, with storage at 6°C. Sperm capacitation‐like status was investigated using the fluorescent dye chlortetracycline (CTC). There was no difference in capacitation‐like status between colloid‐selected and non‐selected spermatozoa. Sperm motility decreased significantly during cold storage, whereas the proportion of apparently capacitated spermatozoa increased. There was no change in the proportion of acrosome‐reacted spermatozoa. In conclusion, SLC through Androcoll?‐E does not adversely affect the capacitation‐like status of stallion spermatozoa, although it did increase with time during cold storage.  相似文献   

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Effective teaching of veterinary radiology can be challenging in a traditional classroom environment. Audience response systems, colloquially known as “clickers,” provide a means of encouraging student interaction. The purpose of this study was to compare student performance and course evaluations before and after using the Classroom Performance System? in the third‐year (fifth semester) didactic radiology course at the University of Tennessee College of Veterinary Medicine. Overall student performance was assessed by comparing median numeric final course grades (%) between years without and with use of the Classroom Performance System?. Grades of students were determined for individual instructors’ sections. Student evaluations of the radiology course were compared for the years available (2007–2010). Student interactions were also evaluated subjectively by instructors who used the Classroom Performance System?. There was a significant difference (p = 0.009) between the median student grade before (2005 – 2008, median 82.2%; interquartile range 77.6–85.7%; range 61.9–95.5%) and after use of the classroom performance system (2009–2010, median 83.6%; interquartile range 79.9–87.9%; range 68.2–93.2%). There was no statistically significant difference in median student grades for individual instructors over the study period. The radiology course student evaluation scores were significantly higher in years where the Classroom Performance System? was used in comparison to previous years (P = 0.019). Subjectively, students appeared more involved when using clickers. Findings indicated that the Classroom Performance System? may be a useful tool for enhancing veterinary radiology education.  相似文献   

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For 20 years, the cold temperature/S10/von Hagens' plastination technique was used to preserve biological specimens without challenge. It became the “gold standard” for preservation of beautiful, dry biological specimens. Near the end of the 21st century, a group from the University of Michigan and environs and Dow Corning?, USA, combined silicone ingredients, similar to the von Hagens' plastination products, however in a different sequence. The new polymer (Cor‐tech) was combined with the cross‐linker to design the “impregnation mix” which would invade the cellular structure of the specimen and yet was stable at room temperature. Later, curing would be by application of the catalyst onto the impregnated specimen. This unique sequencing of products would become the “Room temperature/Dow Corning?/Corcoran—Silicone plastination technique.” The results of this room temperature technique provided similar plastinates, beautiful and practical for demonstration, containing no toxic chemical residues and forever preserved. As the name implies, impregnation of this silicone mix could be done at room temperature, without having to be kept cold. Both processes (cold and room temperature) required the same four basic steps for plastination. As well, both processes used similar basic polymers and additives to produce plastinates. However, they were combined in a different sequence. Cold temperature combines polymer and catalyst/chain extender, which is not stable and therefore must be kept colder than ?15°C, while room temperature combines polymer with cross‐linker which is stable, and likely forever.  相似文献   

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Routinely, swim‐up method is used to separate high‐quality sperm; however, long processing time and close cell‐to‐cell contact during the centrifugation step are inevitable elements of oxidative stress to sperm. The objective was to evaluate Sephadex? and glass wool filtration to separate motile, intact and viable sperm for in vitro fertilization in buffalo. The cumulus–oocyte complexes (COC s) were collected from ovaries of slaughtered buffaloes by aspiration and matured for 24 hr in CO 2 incubator at 38.5°C and 5% CO 2. Matured COC s were rinsed twice in fertilization TALP and placed in the pre‐warmed fertilization medium without sperm. Cryopreserved buffalo semen was thawed at 37°C for 30 s and processed through Sephadex?, glass wool filtration and swim‐up (control). Total and motile sperm recovery rates were assessed, resuspended in fertilization TALP and incubated for 15–20 min in CO 2 incubator. Samples prepared by each method were divided into two aliquots: one aliquot was studied for sperm quality (progressive motility, membrane integrity, viability, liveability), while the other was subjected to co‐incubation with sets of 10–15 in vitro matured oocytes. Data on sperm quality were analysed by ANOVA , while in vitro fertilizing rates were compared by chi‐squared test using SPSS ‐20. Least significant difference (LSD ) test was used to compare treatment means. Glass wool filtration yielded higher total and motile sperm recovery rate, while Sephadex? filtration improved (<  .05) sperm quality (progressive motility, membrane integrity, viability, liveability). Sperm preparation through Sephadex filtration yielded higher in vitro fertilization rate in terms of cleavage rate compared to glass wool filtration and swim‐up (control). In conclusion, cryopreserved Nili‐Ravi buffalo sperm selected through Sephadex filtration showed improved quality and yielded better fertilization rates (cleavage rate) of in vitro matured/fertilized oocytes. Sephadex filtration could be a promising technique for use in in vitro fertilization in buffalo.  相似文献   

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To try new acrosomal probes for assessing ram spermatozoa, we compared the LysoSensor? probe, which labels acidic organelles, with the frequently used peanut agglutinin acrosomal probe (PNA‐PE; phycoerythrin as fluorescent moiety). The previous microscopic observations showed a lack of relationship of LysoSensor? with acrosomal status. Semen was obtained from five rams and frozen in four pools. Each pool was analysed carrying out a triple staining propidium ioide/PNA‐PE/LysoSensor? Green DND‐189 to test acrosome labelling, and a double staining SYBR‐14/PI, to assess sperm viability. Stained samples were analysed by flow cytometry. All measurements were replicated. Data were processed using agreement and repeatability tests. LysoSensor? labelling did not agree with PNA (mean of differences: 30.8%; coefficient of agreement: 22.6%), confirming microscopic observations. Nevertheless, when LysoSensor? was compared with SYBR‐14/PI, the agreement was high (mean of differences: ?0.05%; coefficient of agreement: 5.07%). Repeatability of both methods was high and similar. LysoSensor? did not seem to specifically stain the acrosome, but it may accumulate in the cytoplasm and label viable spermatozoa. Therefore, LysoSensor? might not be used as an acrosomal probe in ram spermatozoa, but it could be used in other kind of studies, taking advantage of its pH sensitivity.  相似文献   

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Objective To compare the Welch Allyn SureSight? wavefront autorefractor with retinoscopy in normal dogs. Animals studied Fifty privately owned dogs (100 eyes) of 20 breeds, free of ocular disease. Mean ± SD age: 5.7 ± 3.25 years (range: 6 months–13 years). Procedures The refractive error was determined in each eye by two experienced retinoscopists using streak retinoscopy as well as by an autorefractor operated by two different examiners. Measurements were performed before and approximately 30–45 min after cycloplegia was induced by cyclopentolate 0.5% and tropicamide 0.5% ophthalmic solutions. Results Mean ± SD noncyclopleged retinoscopy net sphere was ?0.55 ± 1.14 (range: ?3.75 to 3.5) diopters (D). Mean cyclopleged retinoscopy net sphere was ?0.52 ± 1.18 (range: ?4.25 to 2) D. Mean ± SD noncyclopleged autorefractor spherical equivalent (SE) was ?0.42 ± 1.13 D (range: ?3.36 to 2.73) D. Mean cyclopleged autorefractor SE was 0.10 ± 1.47 (range: ?5.62 to 3.19) D. Noncyclopleged autorefraction results were not significantly different from streak retinoscopy (whether noncyclopleged or cyclopleged, P = 0.80 and P = 0.26, respectively). Cyclopleged autorefraction results were significantly different from noncyclopleged or cyclopleged streak retinoscopy (P < 0.0001 in both states). There was no significant difference between noncyclopleged and cyclopleged streak retinoscopy (P = 0.97). Conclusions Noncyclopleged autorefraction shows good agreement with streak retinoscopy in dogs and may be a useful clinical technique. Cycloplegia does not significantly affect streak retinoscopy results in dogs.  相似文献   

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The objective of this study was to determine whether intestinal blood flow can be measured adequately in group-housed animals using the recently developed Physiogear™ I wireless flowmeter. We used the weaner pig as one of many possible animal models. Four 7-kg piglets were instrumented with a 3-mm flowprobe around the superior mesenteric artery (SMA) and SMA flow was measured pre- and post-weaning. During measurements, behavior was recorded. The piglets did not show any abnormal behavior and were not restrained by the flowmeter. Severe reductions (> 75%) in SMA flow coincided with nursing (pre-weaning) and aggressive behavior (post-weaning) and were only short-lived. Our results demonstrate that the Physiogear™ I flowmeter can be used to measure flow in group-housed animals without any human contact, providing the opportunity to relate flow measurements to undisturbed animal behavior.  相似文献   

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Soon after Ovuplant™, the sustained-release implant containing the gonadotropin releasing hormone (GnRH) agonist deslorelin, was approved for commercial use in the United States for induction of ovulation in mares, anecdotal field observations were reported that some Ovuplant™—treated mares that did not become pregnant experienced a delayed return to estrus and prolonged inter-ovulatory interval. Although those observations have been subsequently confirmed, further data on how mares respond to Ovuplant™ compared to human chorionic gonadotropin (hCG) during the post-treatment period is needed. The objective of this study was to further evaluate the clinical use of Ovuplant™ by comparing the reproductive performance of commercial broodmares treated with hCG or Ovuplant™. This retrospective study was completed by examining the 1999 reproductive records of 106 mares treated with hCG during 134 estrous cycles and 117 mares treated with Ovuplant™ during 151 estrous cycles. There were no differences (P > 0.10) in follicle size at the time of treatment (39.4 ± 0.5 vs. 38.9 ± 0.5 mm), interval from treatment to ovulation (2.2 ± 0.1 vs. 2.2 ± 0.1 days), proportion of mares that failed to ovulate after treatment (3.0 vs. 4.6 %), or per-cycle pregnancy rate (47.7 vs. 51.4 %) between hCG-and Ovuplant™-treated mares, respectively. The interval from ovulation to return to estrus (25.8 ± 1.3 vs. 15.5 ± 0.6 days) and the inter-ovulatory interval (30.4 ± 1.5 vs. 20.8 ± 0.6 days) were longer (P<0.001) for Ovuplant™-compared to hCG-treated mares, and the proportion of non-pregnant mares that failed to return to estrus within 30 days after ovulation (31.4 vs. 1.5 %) was higher (P<0.001) for Ovuplant™-compared to hCG-treated mares, respectively. For Ovuplant™—treated mares, follicle size at the time of treatment tended (P<0.1) to be smaller for mares that failed to return to estrus within 30 days compared to mares that returned to estrus within 30 days (37.1 ± 1.1 vs. 40.1 ± 0.6 mm, respectively). Also, the average date of ovulation during the calendar year was later (P < 0.05) for Ovuplant™—treated mares that failed to return to estrus within 30 days compared to those that returned to estrus within 30 days (May 15 ± 4 vs. April 30 ± 4 days). The results of this study confirm previous reports that although the ovulatory response and fertility were not different for hCG- and Ovuplant™—treated mares, mares treated with Ovuplant™ that did not become pregnant had a significantly delayed return to estrus and prolonged inter-ovulatory interval. Based on recently published information, it appears this effect is due to Ovuplant™—induced down-regulation of the pituitary gland, which suppresses subsequent follicular growth and development. This study also demonstrated that follicle size and/or season may influence the probability that Ovuplant™—treated mares would experience a delayed return to estrus/ovulation; therefore, further work is needed to determine whether these or other factors are related to this specific outcome following Ovuplant™—treatment.  相似文献   

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