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101.
100只1日龄艾维茵肉鸡随机分成2组(50×2)饲喂钙、磷含量不同的饲料.组I钙、磷含量基本正常,组Ⅱ钙偏低、且钙、磷比例不平衡,每周每组急杀5只,检测胫骨灰化度、血钙和血清无机磷浓度.组I骨灰化度曲线呈“S”状;血钙曲线呈驼峰状且在4周龄达到最高值(21.6mg/100ml);血磷曲线呈倒“S”状,并在3~4周龄形成底谷.组Ⅱ骨灰化度曲线呈双“S”型.即在3~4周龄时出现一个缓坡;血钙曲线为倒“S”状并在3~4周龄时形成底谷;血磷曲线略呈直线下降.结果表明,肉用仔鸡骨骼形成的主要时期在2~5周龄,佝偻病发生的敏感时期在3~4周龄. 相似文献
102.
Background
Heart rate and plasma cortisol concentration are often used in evaluation of physiological reactions to stress and fear, but arterial blood pressure is rarely measured in farm animals. Goats are prey animals and can be expected to react strongly to a predator, especially when they have kids. We hypothesized that exposure to a dog elicits a flight response during pregnancy and a fight response when goats have kids to defend. Arterial blood pressure and heart rate should increase in both these cases, due to a synchronized discharge of the sympathetic nervous system.Methods
Seven goats were exposed to a dog for 15 minutes at 12 ± 3 days before, and again at 10 ± 1 days after, parturition. Arterial blood pressure, heart rate, and activity were registered by telemetry. Behavioral data were collected during 5 minute sessions, followed by blood samples obtained via intrajugular catheters. Plasma cortisol concentration was analyzed by radioimmunoassay.Results
At the appearance of the dog, the mean arterial blood pressure of the goats increased from 90 ± 8 to 111 ± 8 mmHg (p < 0.001) during pregnancy and from 96 ± 8 to 108 ± 8 mmHg during lactation (p < 0.001). Heart rate did not change at dog exposure during lactation, but increased from 117 ± 6 to 126 ± 10 beats/min (p < 0.01) during pregnancy. Dog exposure resulted in plasma cortisol concentration increasing from 17 ± 1 to 43 ± 7 nmol/l (p < 0.01) during pregnancy and from 21 ± 1 to 49 ± 6 nmol/l (p < 0.01) during lactation. In response to the dog, goats vocalized at a higher frequency and started to ruminate later during lactation compared to pregnancy.Conclusions
When goats were exposed to a dog during pregnancy, their heart rate, blood pressure, and plasma cortisol increased, in contrast to lactation when only their blood pressure and plasma cortisol increased. However, when they were lactating, goats vocalized more and started to ruminate later compared to when they were pregnant. 相似文献103.
本文应用弹簧式血压计测定了144头中国黑白花奶牛尾动脉压,并就添加钠钾对血压的影响作了初步探讨。结果表明,用此型血压计测定奶牛尾动脉压是可行的;成奶牛尾动脉收缩压为137.10+16.32mmHg,舒张压为44.63±14.72mmHg;日粮添加钠钾可使血清钠钾浓度显著升高,尾动脉收缩压显著升高(P<0.05),舒张压极显著升高(P<0.01);建议改血压计气袋为梯形,以减少气袋与尾动脉接触不紧对血压值的影响。 相似文献
104.
《Journal of Exotic Pet Medicine》2014,23(2):129-141
Blood pressure monitoring of patients has become increasingly common in companion animal veterinary hospitals, especially during anesthesia, surgical procedures, critical care, and general health assessments. Determining an animal’s blood pressure has become a standard part of the routine diagnostic evaluation for monitoring hypertension in geriatric patients or patients affected with renal insufficiency, cardiac disease, vision loss, or endocrine disorders. To increase the standard of care in exotic and zoological medicine, new diagnostic techniques must be identified and implemented. Blood pressure measurements in avian species are more challenging because only direct blood pressure techniques have been reported to be accurate. Arterial catheterization and interpretation can be daunting without the knowledge of avian physiology and anatomy; however, techniques for placing arterial catheters are not difficult once clinicians have gained sufficient experience. This article describes the techniques, anatomy, and appropriate interpretation of blood pressure results obtained through arterial catheterization in birds. 相似文献
105.
CASE HISTORY: Death occurred in a 1.25 kg, 9-month-old female Pomeranian dog undergoing anaesthesia for surgical repair of partially healed fractures of the radius and ulna. CLINICAL FINDINGS: Following sedation, anaesthesia was induced using thiopentone and maintained with halothane in oxygen. An acute decrease in the dog's end-tidal carbon dioxide (EtCO2) measurements was noted approximately 50 min after induction, immediately following delivery of a 5-ml bolus of lactated Ringer's solution (LRS) administered to flush a small (0.06 ml) volume of fentanyl via a pre-placed intravenous (I/V) catheter. Venous air embolism (VAE) was suspected and the dog died despite interventive therapy. On post-mortem examination, several air bubbles were noted when the right ventricle was opened under water. Histologically, the kidneys appeared abnormal with immature glomeruli, and the lungs appeared diffusely mineralised. The origin of the air was probably small bubbles and microbubbles that may have been present in the extension set and 20 ml syringe used for the administration of fentanyl and I/V fluids to the dog. DIAGNOSIS: Renal dysplasia and diffuse pulmonary calcification, with VAE as the probable cause of death. CLINICAL RELEVANCE: In this case of VAE-associated anaesthetic death, it is further speculated that underlying pulmonary disease, in the form of pulmonary calcification, may have contributed to an increased sensitivity to the adverse effects of VAE. 相似文献
106.
Elena R Moldal Thomas Eriksen Jolle Kirpensteijn Ane Nødtvedt Annemarie T Kristensen Fiorella M Sparta H Andreas Haga 《Veterinary anaesthesia and analgesia》2013,40(1):63-73
ObjectiveTo evaluate the usefulness of intratesticular and subcutaneous lidocaine in alleviating the intraoperative nociceptive response to castration, measured by pulse rate (PR) and mean arterial pressure (MAP), and to test the applicability of heart rate variability (HRV) analysis in assessing this response.Study designRandomized, controlled, observer-blinded experimental trial.AnimalsThirty-nine healthy male cats admitted for castration.MethodsOne group received general anaesthesia and served as control group (GA), while the treatment group (LA) additionally received local anaesthesia (lidocaine 2 mg kg?1) intratesticularly and subcutaneously. PR and MAP were recorded at anaesthesia baseline (T0), treatment (T1), incision left testicle (T2), traction on spermatic cord (T3), tightening of the autoligature and resection of the cord (T4), incision on the right side (T5), traction on spermatic cord (T6), and tightening of the autoligature and resection of cord (T7). HRV analysis was divided into three 5-minute intervals: baseline (H0), treatment (H1), and surgery (H2).ResultsThere were significant increases in PR and MAP for both groups during surgery from T3 onwards; however, the increase in the treatment group (LA) was significantly lower than for the control group (GA). For HRV analysis, significant differences were found between groups in the following parameters during surgery: TP (total power), VLF (very low frequency), SDNN (standard deviation of NN intervals [=the interval between two consecutive R-waves in the ECG]), and TI (triangular index), which were lower in the LA group. Mean NN was significantly lower in the GA group, whereas LF (low frequency) and LFn (low frequency, normalized value) were lower in the LA group. HF (high frequency) and HFn (high frequency, normalized value) decreased significantly from H1 to H2 in both groups.Conclusions and clinical relevanceThe study showed that the nociceptive response to surgery was alleviated by the use of intratesticular and subcutaneous lidocaine and that HRV analysis is a promising research tool to estimate intraoperative nociception in cats during general anaesthesia. 相似文献
107.
108.
褐藻酸钠可食性膜制备工艺研究 总被引:1,自引:0,他引:1
以褐藻酸钠、羟丙基甲基纤维素为原材料,通过混合水平正交试验,使用溶胶、混胶、脱气、倒胶、钙化、干燥工艺制备可食性膜,研究了不同褐藻酸钠/羟丙基甲基纤维素配比、溶胶温度、氯化钙质量浓度、钙化时间、褐藻酸钠质量浓度以及羟丙基甲基纤维素质量浓度对膜性能的影响,结果显示优化工艺参数为:10mg/mL褐藻酸钠和50mg/mL羟丙基甲基纤维素按质量配比1∶1混胶,10mg/mL的氯化钙钙化10min;所得膜的厚度为0.14mm,抗拉强度为2.97 MPa,透光率为64.09%,干燥质量损失率为9.97%,人工胃液崩解时间超过24h,人工肠液崩解为2.07h。本工艺较为简单,成膜性较好,为进一步制备植源性空心硬胶囊壳奠定理论和实践基础。 相似文献
109.
用猪囊尾蚴细胞苗对一万余头仔猪进行免疫,通过ELISA法,经屠宰调查,其有效保护率达96.93%,表明该细胞苗具有良好的免疫保护力,为防制猪囊虫提供了有效的技术手段. 相似文献
110.
Ninomiya H 《Veterinary ophthalmology》2002,5(3):155-160
Vasculature of the ophthalmic rete (rete ophthalmicum) in the night heron (Nycticorax nycticorax) was studied using scanning electron microscopy of vascular corrosion casts and light microscopy on tissue sections. Most blood to the eyeball and a lesser volume of blood to the brain passed through the ophthalmic rete via the external ophthalmic artery. The collateral retial arterioles originated from the external ophthalmic artery forming a flat and fusiform-shaped arterial network at the ventrotemporal region of the eyeball. The arterial network was intermixed with a similar complex of the veins from the eye. The ophthalmotemporal artery, which supplied the eyeball posteriorly, and supraorbital and infraorbital arteries, which supplied the eyeball anteriorly, originated from the rete. Blood from the eye, which is a site of potential heat loss, drained into the ophthalmic rete via the ophthalmotemporal vein. On the casts of retial arterioles, slit-like cleavages at branching sites representing flap valves, which might play a role as sluice valves, were seen. In addition, marks of circularly running grooves, which might represent tufts of smooth muscle cells and might contribute to a sphincter activity, were observed. These anatomical specializations of the avian ophthalmic rete, involving parallel arrangement of arteries and veins, may function to facilitate counter-current heat exchange and to regulate blood pressure and volume to the eye and the brain. 相似文献