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411.
为进一步分析黑色素皮质激素受体-1(melanocortin-1 receptor,MC1R)基因的分子特性,利用生物信息学方法对GenBank中已报道的赤狐MC1R基因完整编码区序列的碱基组成特点及其编码蛋白的结构特征进行了预测及分析,构建了12个物种MC1R蛋白的系统进化树。结果表明,赤狐MC1R基因编码区序列长度为954 bp,共编码317个氨基酸,为单一外显子,G+C含量高于A+T,编码的蛋白质是一种分子质量为34.8694 ku,等电点为9.13的亲水性稳定碱性蛋白;存在7个强跨膜区、7个广泛磷酸化位点和1个潜在的蛋白激酶C磷酸化位点(第157位的苏氨酸),α-螺旋为其主要二级结构元件;属于G蛋白偶联受体家族一员,包括多个潜在重要功能基序;同源性分析与分子进化树结果均表明,赤狐与北极狐、狗和貉的亲缘关系最近。 相似文献
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The objective was to compare horses' maintenance of fitness during extended periods of no forced exercise with that after stall confinement. Horses were divided into three groups: pasture turnout (P), stalled and exercised (E), or stalled with no exercise (S). Pre- and post-study body fat and bone mineral content were estimated, and horses performed a standardized exercise test (SET). Horses wore global positioning units to estimate distance traveled. The P group traveled a greater distance daily compared with the E and S groups (P < .01). Lateral bone density was greater for the P group after the study (P = .05). Comparing first and second SETs, the P group had lower heart rates at the trot (P < .01) and hand-gallop (P = .028), the E group had lower heart rates at the hand-gallop (P < .01), and the S group had higher 1-minute recovery heart rates (P < .01). Plasma lactate concentrations were higher at the peak of exercise (P < .01) and 10-minute recovery (P = .015) for the S group, whereas the P and E groups had lower rectal temperature at the peak of exercise (P = .029) and 10-minute recovery (P = .031 and P = .041, respectively). These data suggest that the S group lost fitness, whereas the P group remained as fit as the E group. The improvement for the P group compared with the E or S group was greater bone mineral content. Access to pasture appears to help maintain bone strength and exercise fitness ability. 相似文献
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Abstract Extract Most perennial ryegrass (Lolium perenne) plants in pastures in New Zealand contain a naturally occurring fungal endophyte, Neotyphodium lolii. Endophyte-infected perennial ryegrass produces alkaloids that vary in concentration during the year. Some alkaloids enhance the persistence and productivity of ryegrass pastures by protecting them against insect attack. However, when other alkaloids are consumed they can reduce animal performance and lead to health problems. The alkaloid lolitrem B, for example, causes the neuromuscular disorder ryegrass staggers (Fletcher et al 1999). Clinical symptoms of ryegrass staggers in animals range from slight muscular tremors through to staggering and complete collapse. Severely affected animals create management problems and are prone to accidental death. Outbreaks occur sporadically, particularly in summer and autumn and affect sheep, cattle, deer, horses, llamas (Lama glama) and alpaca (Lama pacos). Lolitrem B appears to be a stable compound, which tends to be concentrated in the leaf sheath at the base of the ryegrass plant and in the seed-heads (di Menna et al 1992; Keogh et al 1996). Hay made from endophyte-infected perennial ryegrass contains large numbers of seed-heads and lolitrem B concentrations can be high, especially if it is made in late summer or autumn and, consequently, animals fed such hay are at risk of developing ryegrass staggers. 相似文献
416.
BD Gartrell E Jillings BA Adlington H Mack NJ Nelson 《New Zealand veterinary journal》2013,61(6):344-349
AIMS: To screen tuatara undergoing translocation from a captive crèche to an island refuge for evidence of health and known diseases, and apply basic epidemiological techniques to assess the significance of disease test results. METHODS: Tuatara (n=353) were physically examined and samples were taken from a random selection (n=30) for estimated white cell counts, screening for haemoparasites, and culture for Salmonella, Yersinia, Aeromonas and Campylobacter spp. Direct faecal smears were carried out on-site, and faecal floats were later performed to assess levels of endoparasitism with helminths and protozoa (n=69). Modified Ziehl-Neelsen staining was used to screen faecal smears, and positive specimens were further screened using an immunofluorescence antibody (IFA) test for Cryptosporidium oocysts. RESULTS: There was no evidence of external parasites on any of the animals examined and only one animal had a gross abnormality. All estimated white cell counts were in the range 2.8– 17.5 × 109/L. No haemoparasites were observed. There were no enteric pathogens cultured, indicating the intestinal carriage of these bacteria in the tuatara was 9.4%. Of the 69 individual faecal samples examined, 12 (17%) had unidentified coccidial oocysts, 21 (30%) had nematode ova of various kinds, and 12 (17%) had intestinal carriage of motile protozoa consistent with Trichomonas spp and another unidentified organism. Nineteen (28%) tuatara had acid-fast oocysts present; however, IFA staining failed to detect any Cryptosporidium oocysts. CONCLUSIONS: Our understanding of the diversity of gastrointestinal endoparasites affecting tuatara is inadequate as many of the parasite ova seen could not be identified. This is the first record of tuatara as a host for Trichomonas spp of protozoa in the gastrointestinal tract. 相似文献
417.
Sheila M. Etue DVM Dominique G. Penninck DVM DVSC Mary Anna Labato DVM Susan Pearson BA CVT Amy Tidwell DVM 《Veterinary radiology & ultrasound》2001,42(4):330-336
The sonographic appearance of the feline pancreas and associated anatomic landmarks including the pancreatic duct, duodenum, duodenal papilla, portal vein, and gastric lymph node were evaluated in 20 healthy, awake cats. The pancreas appeared nearly isoechoic to surrounding mesenteric tissues, isoechoic to slightly hyperechoic to adjacent liver lobes, and hypoechoic to the spleen. The mean thickness measurements for the right pancreatic lobe, body, and left pancreatic lobe were 4.5 mm (range 2.8-5.9), 6.6 mm (range 4.7-9.5), and 5.4 mm (range 3.4-9.0), respectively. The pancreatic duct was consistently visualized in the left pancreatic lobe and had a mean thickness of 0.8 mm (range 0.5-1.3). It could be differentiated from the pancreatic vessel, by its central location, and the duct's lack of Doppler flow signal. The duodenum was used as a landmark to identify the right lobe of the pancreas. The mean duodenal wall thickness measurement was 2.8 mm (range 2.1-3.8) in sagittal section, and 3.0 mm (range 2.2-4.4) in transverse section. The duodenal papilla was identified in 4 of 20 cats. It ranged in size from 2.9 to 5.5 mm in width, and had a maximum height of 4.0 mm in transverse section. The portal vein was used as a consistent anatomic landmark for identification of the left lobe and body of the pancreas. The mean diameter of the portal vein at the level where the pancreatic body joins the left pancreatic lobe was 4.3 mm (range 2.7-5.9) when viewed in sagittal section, and 4.5 mm (range 3.6-6.1) in transverse section. The gastric lymph node was identified cranial and ventromedial to the pyloroduodenal angle in 6 of 20 cats. It had an asymmetrical shape with a larger caudal pole in five of the six cats. The largest dimensions of the gastric lymph node were 10 mm in length, and 6 mm in width for the larger caudal pole, and 5.1 mm in width for the smaller cranial pole. 相似文献
418.
Matthew W. Beal DVM DACVECC Arin M. Doherty BA Keith Curcio DVM DACVS 《Journal of Veterinary Emergency and Critical Care》2008,18(4):388-392
Objective: To describe the clinical course of a dog presented with peliosis hepatis and hemoperitoneum in concert with anticoagulant rodenticide intoxication.
Case summary: A 7.75-year-old spayed female Shetland Sheepdog presented with clinical signs consistent with hypovolemia, hemoperitoneum, and a history of bright green stool 3 days before the onset of clinical signs. Initial packed cell volume/total solids were consistent with acute hemorrhage. A coagulation profile showed prolongation in activated clotting time and prolongation of both prothrombin and activated partial thromboplastin time, suggesting abnormal coagulation. Abdominal hemorrhage persisted in the face of normalization of the hemodynamic status and coagulation profile, and treatment with Vitamin K1 . Abdominal ultrasound revealed multiple patchy hypoechoic areas throughout the caudate liver lobe. An exploratory laparotomy was performed 24 hours after presentation and revealed the caudate liver lobe as the source of the hemorrhage. Histopathologic examination of a specimen of the liver was consistent with peliosis hepatis. Toxicologic testing identified diphacinone levels in the blood consistent with anticoagulant rodenticide intoxication. Postoperative recovery was uneventful, and within 48 hours the dog was discharged. The dog returned to full function and a hepatic ultrasound performed 15 months postoperatively showed no significant abnormalities.
New or unique information provided: Exposure to anticoagulant rodenticides may be associated with the development of peliosis hepatis in dogs. 相似文献
Case summary: A 7.75-year-old spayed female Shetland Sheepdog presented with clinical signs consistent with hypovolemia, hemoperitoneum, and a history of bright green stool 3 days before the onset of clinical signs. Initial packed cell volume/total solids were consistent with acute hemorrhage. A coagulation profile showed prolongation in activated clotting time and prolongation of both prothrombin and activated partial thromboplastin time, suggesting abnormal coagulation. Abdominal hemorrhage persisted in the face of normalization of the hemodynamic status and coagulation profile, and treatment with Vitamin K
New or unique information provided: Exposure to anticoagulant rodenticides may be associated with the development of peliosis hepatis in dogs. 相似文献
419.
PEDV分离株S1基因的重组杆状病毒真核表达 总被引:1,自引:1,他引:0
为了研究猪流行性腹泻病毒(porcine epidemic diarrhea virus,PEDV)分离株(PEDV/LA/2014/02)纤突蛋白(S1)的真核表达及其反应原性,本研究利用杆状病毒真核表达系统表达出重组His-PEDV-S1蛋白。利用在线软件分析PEDV S1基因在sf9细胞内的稀有密码子,经优化密码子后的基因进行人工合成,合成后的PEDV S1基因被克隆至杆状病毒的穿梭载体(pFastBac HT A)中,转化大肠杆菌DH10Bac感受态细胞进行重组,PCR方法验证后将重组成功的杆状病毒基因组转染sf9细胞,获得包装成功的杆状病毒,该病毒进一步接种sf9细胞,显微镜观察重组病毒引起的细胞病变,RT-PCR方法验证PEDV S1基因的mRNA表达水平,SDS-PAGE、Western blotting方法验证重组PEDV S1蛋白的表达及其反应原性。结果显示,试验成功构建了重组穿梭质粒pFastBac HT A-PEDV-S1(pSL598),成功包装表达了PEDV S1的重组杆状病毒,重组杆状病毒能使sf9细胞出现细胞变大、胞内有空泡等典型病变,PEDV S1基因的mRNA获得表达,重组蛋白His-PEDV-S1在sf9细胞中得到表达,蛋白质大小为83 ku左右,主要存在于细胞沉淀中,表达的重组蛋白能与小鼠抗His抗体和猪抗PEDV阳性血清反应,说明该蛋白具有较好的反应原性。本研究为研制PEDV新流行毒株新型亚单位疫苗和防控该毒株的流行提供了材料。 相似文献
420.