Evaluation of the white-coat effect in cats

The diagnosis and management of systemic hypertension in cats requires a reliable method for measurement of systemic arterial blood pressure (BP) in clinical patients. Unfortunately, the setting of a clinical practice and the act of measuring BP might raise BP and heart rate (HR), an effect referred to as the white-coat effect in human patients. The purpose of the present study was to determine if a white-coat effect was experienced by cats. Radiotelemetric implants were used to measure BP and HR in 13 conscious cats in a research colony while undisturbed in their cages and while subjected to simulated visits to a veterinarian's office. The white-coat effect was taken to be the difference between the overall 24-hour average value for parameters of BP and HR and the corresponding value during the simulated office visit. A white-coat effect was observed in cats. In healthy cats, the systolic BP measured during the examination period of the simulated office visit exceeded the 24-hour average systolic BP by 17.6+/-1.5 mm Hg. However, marked heterogeneity occurred in the pattern and magnitude of the increase in systolic BP above the 24-hour baseline and the increase varied between 75.3 and -27.2 mm Hg for the healthy cats. Variation in response to the simulated office visit was observed among cats and among visits by the same cat. During an office visit, the magnitude of the white-coat effect tended to decrease, but not disappear, over time. The magnitude of the white-coat effect varied when cats were subjected to 5 repeat office visits, but did not diminish in the group as a whole. The mean increase in systolic BP during the examination (22.3+/-0.9 mm Hg) was greater (P < .05) in cats with renal insufficiency. Although the heterogeneity of response expected from companion animals might be greater than that observed in these colony cats, these results indicate that veterinarians should carefully consider the white-coat effect in evaluation of BP in cats. A quiet, undisturbed environment and adequate time for acclimation should be included in the standard protocol for measurements of BP. Because of day-to-day variation in the white-coat effect in individual cats, multiple serial measurements following a standard protocol should provide the best estimate of BP in cats.     

Percutaneous, ultrasonographically guided technique of catheterization of the abdominal aorta in calves for serial blood sampling and continuous arterial blood pressure measurement

The study describes a technique of ultrasonographically guided transcutaneous catheter implantation into the abdominal aorta of 29 6- to 8-week-old German Holstein calves. Catheters were implanted between the left transverse processes of L3 and L4, left in place for 2 days and used for serial blood sampling and continuous measurement of blood pressure. Complete cell counts and clinical examination were performed before, as well as 1 and 5 days after implantation. Catheterization was successful in all calves. The catheter was patent for blood sampling and pressure recordings at all times. A significant decrease in red blood cells was found in all animals after catheterization, which remained reduced for 5 days. Clinical signs of anaemia were absent. In conclusion, ultrasonographically guided catheterization of the abdominal aorta provides a continuous arterial access in calves, whereby the minimal invasive technique and the ultrasonographical guidance reduces accidental tissue trauma and pain for the animal.     

Intraocular pressure development after cataract surgery: a prospective study in 50 dogs (1998-2000)

Objective To study the course of intraocular pressure (IOP) after cataract surgery in 50 dogs. Design Prospective study. Animals Fifty dogs without preoperative ocular hypertension were selected for cataract surgery. Methods All dogs underwent cataract surgery: 25 by manual extracapsular extraction and 25 by phacoemulsification. For each dog, intraocular pressure was measured before surgery, and 1, 3, 5, 18 h, 1 week and 1 month post surgery. Results No significant difference of mean intraocular pressure between the two surgical methods was observed for each time measurement. Nine dogs had postoperative hypertension (IOP > 25 mmHg) during the first 5 hours post surgery. Incidence of postoperative hypertension was not significantly different with manual extracapsular extraction (16%) vs. phacoemulsification (20%). A decrease of mean IOP was observed 1 h after surgery (8.49 mmHg vs. 10.91 mmHg), then an increase 3 and 5 h post surgery (12.3 and 13.32 mmHg, respectively). At 18 h, 1 week and 1 month post surgery, mean IOP decreased. Mean IOP was 10.38, 10.38 and 8.84 mmHg, respectively. Conclusion In this study incidence of POH is not high. However, a follow‐up of IOP in the first hours after cataract surgery is required to avoid complications of the retina and optic nerve and to administer hypotensive treatment if necessary.     

Effect of topical anesthesia on evaluation of corneal sensitivity and intraocular pressure in rats and dogs

Objective To determine the effect of 0.5% proparacaine in tonometry by evaluating corneal touch threshold (CTT) and intraocular pressure (IOP). Animal studied Nine rats (18 eyes, Sprague–Dawley) and 10 dogs (20 eyes, Beagle) Procedures The IOP and CTT were measured in each eye before and after topical anesthesia with 0.5% proparacaine. The IOP was evaluated using Tonopen for dogs and Tonolab for rats. The corneal sensitivity was evaluated by CTT through a Cochet–Bonnet aesthesiometer. Results The mean IOP was not significantly changed in rats or dogs before and after topical anesthesia. However, after application of proparacaine, CTT was significantly increased in both animal groups compared with that before application of proparacaine. Conclusion From this study, topical anesthesia was found to significantly lower the corneal sensitivity but have little effect on IOP measurements. In ophthalmologic examination, topical anesthesia can be used to reduce corneal sensation without an effect on IOP.     

Comparison of a rebound and an applanation tonometer for measuring intraocular pressure in normal rabbits

Objective To compare intraocular pressure (IOP) measurements made on healthy adult rabbits without the effect of tranquilizers using the new applanation tonometer, Tono‐Pen Avia^®, and the rebound tonometer Tonovet^®. Methods Intraocular pressure was measured throughout the day (6:00, 9:00, 12:00, 15:00, and 18:00 h) in 38 adult New Zealand White rabbits (76 eyes). The animals were 20 males and 18 females, with a mean weight of 3.5 kg and an average age of 6 months. A complete ocular exam (including Schirmer tear test, fluorescein staining, slit‐lamp biomicroscopy, and direct ophthalmoscopy) was performed on all animals at the beginning of the trial. Rebound tonometry was performed, and after 10 min, anesthetic drops were instilled and applanation tonometry was carried out. IOP values obtained using the two techniques were analyzed statistically. Results The mean IOP was 9.51 ± 2.62 mmHg with Tonovet^®, and 15.44 ± 2.16 mmHg with the Tono‐Pen Avia^®. Significant differences between measurements with the two tonometers were observed (P < 0.001). The linear regression equation describing the relationship between the two tonometers was y = 0.4923x + 10.754 (y = Tonovet^® and x = Tono‐Pen Avia^®). High IOPs were recorded in the early measurements (6:00), but the average IOPs from both devices were statistically similar throughout the day (P = 0.086). The correlation coefficient was r² = 0.357. No significant difference in IOP regarding gender was observed. Conclusion The Tono‐Pen Avia^® recorded higher levels of IOP compared with the Tonovet^®. Early in the day, the IOP of rabbits was higher than later in the day, regardless of the tonometer used.     

蚕丝脱胶方法的比较分析

对高温高压水、尿素溶液和碳酸钠溶液煮沸的蚕丝脱胶方法作了比较研究。结果表明 ,蚕丝在高温高压条件下丝胶蛋白易于溶解 ,脱胶率达 80 %以上 ,获得的丝胶分子量大 (10～ 2 0 0kD) ;在碱性的碳酸钠溶液中煮沸脱胶 ,丝胶蛋白易于降解或水解 ,其回收的丝胶分子量 2 0kD以下。蚕丝在高温高压水或高温高压尿素溶液中的脱胶率都随着处理温度和压力的增大而提高 ,而回收的丝胶蛋白分子量随着处理温度和压力的增大而下降。高温高压水蚕丝脱胶法是一种高效率、低成本、无污染的脱胶方法 ,特别适用于绢纺厂、丝棉厂等蚕丝的脱胶与加工以及纺织厂生丝的精练等。     

不同稀释液生理参数对关中奶山羊精液 保存及冷冻效果的研究

[目的]探讨了不同pH值、渗透压的稀释液对关中奶山羊冻精品质的影响,以确定关中奶山羊精液最佳保存与冷冻效果。[方法]通过显微检测在不同pH值、渗透压的稀释液处理对降温前、平衡后与解冻后的精子的活率、复苏率、精子顶体完整率、精子畸形率及精子冻后存活时间等指标进行评估。[结果],关中奶山羊精液稀释液pH值为7.3时,降温前、平衡后与解冻后的精子活率最高,分别达到0.742±0.011%、0.645±0.011%、0.489±0.012%;冻后活率、复苏率及解冻后顶体完整率分别达到0.431±0.009%、63.1±0.427%、65.7±2.018%;精子存活时间在降温前、平衡后及解冻后分别达到12.50±0.141h、11.96±0.186h、11.61±0.753h,冻后 8 h 活率0.52±0.014%;当渗透压为Δ0.754℃时,其精子的保护效果最佳,降温前、平衡后与解冻后的精子活率分别达到0.752±0.045%、0.671±0.024%、0.649±0.036%;冻后活率、复苏率及解冻后顶体完整率分别达到0.481±0.019%、63.6±0.377%、69.9±1.068%;精子存活时间在降温前、平衡后及解冻后分别达到11.82±0.165h、11.94±0.145h、11.70±0.753h,冻后 8 h 活率达到0.43±0.033%。[结论]关中奶山羊精液稀释液最合适的pH值是7.3,最佳渗透压为Δ0.754℃,这一结果对奶山羊稀释液配方优化提供了一定的理论指导。     

超高压均质对牛乳中微生物和酶的影响研究进展

超高压均质作为一种新兴的加工方式,与传统热处理和静态超高压相比,动态超高压处理具有可连续化、经济及热负荷低等诸多优点.随着压力的提高,高压均质带来的剪切、湍流和空化现象急剧增加,产品在处理过程中的温度瞬间增加,这为牛乳的杀菌和灭酶提供了新的途径.本文总结超高压均质在牛乳微生物和酶中的应用研究,现有的研究表明超高压均质对...