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981.
982.
Contrast‐Enhanced Ultrasound Examination for the Assessment of Renal Perfusion in Cats with Chronic Kidney Disease 下载免费PDF全文
E. Stock D. Paepe S. Daminet E. Vandermeulen L. Duchateau K. Vanderperren 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):260-266
Background
Contrast‐enhanced ultrasound examination (CEUS) is a functional imaging technique allowing noninvasive assessment of tissue perfusion. Studies in humans show that the technique holds great potential to be used in the diagnosis of chronic kidney disease (CKD). However, data in veterinary medicine are currently lacking.Objectives
To evaluate renal perfusion using CEUS in cats with CKD.Animals
Fourteen client‐owned cats with CKD and 43 healthy control cats.Methods
Prospective case‐controlled clinical trial using CEUS to evaluate renal perfusion in cats with CKD compared to healthy control cats. Time‐intensity curves were created, and perfusion parameters were calculated using off‐line software. A linear mixed model was used to examine differences between perfusion parameters of cats with CKD and healthy cats.Results
In cats with CKD, longer time to peak and shorter mean transit times were observed for the renal cortex. In contrast, a shorter time to peak and rise time were seen for the renal medulla. The findings for the renal cortex indicate decreased blood velocity and shorter total duration of enhancement, likely caused by increased vascular resistance in CKD. Increased blood velocity in the renal medulla has not been described before and may be because of a different response to regulatory factors in cortex and medulla.Conclusions and Clinical Importance
Contrast‐enhanced ultrasound examination was capable of detecting perfusion changes in cats with CKD. Further research is warranted to assess the diagnostic capabilities of CEUS in early stage of the disease process. 相似文献983.
Effects of Moringa oleifera silage on milk yield,nutrient digestibility and serum biochemical indexes of lactating dairy cows 下载免费PDF全文
B. Zeng J. J. Sun T. Chen B. L. Sun Q. He X. Y. Chen Y. L. Zhang Q. Y. Xi 《Journal of animal physiology and animal nutrition》2018,102(1):75-81
This study investigated the effects of Moringa oleifera (MO) as a partial substitute of alfalfa hay on milk yield, nutrient apparent digestibility and serum biochemical indexes of dairy cows. MO was harvested at 120 days post‐seeding. Fresh MO was cut, mixed with chopped oat hay (425:575 on a DM basis), ensiled and stored for 60 days. Sixty healthy Holstein dairy cows were allocated to one of three groups: NM (no MO or control), LM (low MO; 25% alfalfa hay and 50% maize silage were replaced by MO silage) or HM (high MO; 50% alfalfa hay and 100% maize silage were replaced by MO silage). The feeding trial lasted 35 days. The LM and HM diets did not affect dry matter (DM) intake, milk yield or milk composition (lactose, milk fat, milk protein and somatic cell count). The apparent digestibility of DM and NDF was lower for HM group than NM group. Additionally, there were no significant differences in serum biochemical indexes between the LM and NM groups. The HM group had lower serum concentrations of total cholesterol, high‐density lipoprotein cholesterol, and low‐density lipoprotein cholesterol and higher serum concentrations of urea than the NM group. The partial replacement of alfalfa hay (≤50%) and maize silage with MO silage had no negative effects on milk yield, in vivo nutrient apparent digestibility or serum biochemical indexes of lactating cows. 相似文献
984.
G. F. Difford D. W. Olijhoek A. L. F. Hellwing P. Lund M. A. Bjerring Y. de Haas 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2018,68(1):25-32
This study assessed the ranking of dairy cows using individual-level correlations for methane (CH4) emission on-farm using sniffers and in respiration chambers. In total 20 lactating dairy cows, ten Holstein and ten Jerseys were recorded using sniffers installed in milking robots for three weeks of lactation and subsequently in respiration chambers (RC) where they were each recorded on three occasions within the RC. Bivariate linear mixed models were used to determine the individual-level correlations (rI) between sniffer and RC phenotypes as proxies for genetic correlations. Despite differences in feeding and management, the predicted CH4 production from sniffers correlated highly with RC CH4 production rI?=?0.77?±?0.18 and CH4 breath concentration correlated nearly as well with RC CH4 production rI?=?0.75?±?0.20. These correlations between sniffers on-farm and RC demonstrate the potential of sniffers measurements as large-scale indicator traits for CH4 emissions in dairy cattle. 相似文献
985.
986.
Comparison of diagnostic accuracy of laparoscopic 3 mm and 5 mm cup biopsies to wedge biopsies of canine livers 下载免费PDF全文
987.
在漫长的进化过程中,高等真核生物从原核生物中获取了大量基因,对这些基因进行鉴定分析,可为研究高等植物系统演化及基因组水平比较分析提供理论依据。为了进一步解析大豆和百脉根古老原核基因在其基因组中所起的作用及进化关系,本研究利用生物信息学技术对大豆和百脉根基因组古老原核基因进行全基因组鉴定,并对其特征及功能进行了比较分析。研究结果表明,大豆(40.6%)古老原核基因的占比高于百脉根(33.9%),且多分布于内共生细胞器线粒体、叶绿体中。此外,古老原核蛋白质的结构域在大豆和百脉根基因组中的分布相似,表明其在大豆和百脉根进化过程中具有较高的共线性和保守性。通过GO注释发现大豆与百脉根中古老原核蛋白主要分布在膜系统、细胞、细胞组分中。在分子功能上,大豆古老原核蛋白更多地参与代谢和发育过程,这可能与其接受了更多的人为选育有关。在生物过程中,古老原核蛋白更多参与催化反应和结合反应,主要以酶的形式在发挥作用。通过比较分析,本研究揭示了古老原核蛋白在大豆和百脉根中进化的独特模式,可为其他豆科植物基因组分析提供一定理论基础。 相似文献
988.
989.
V. Sandilands F. Whyte L. K. Williams T. S. Wilkinson N. H. C. Sparks T. J. Humphrey 《British poultry science》2018,59(6):698-702
ABSTRACT1. Chicken-associated Campylobacter spp. are the cause of most food poisoning cases in Europe. In order to study the host–pathogen interactions, a reliable and reproducible method of colonising chickens with the bacteria is required.2. This study aimed to identify a more appropriate and less invasive method of colonisation (cf. gavaging) by seeding bedding material (litter) that commercial chickens are kept on with a mixture of Campylobacter spp., broth and faeces.3. The first phase of the study tested the longevity of Campylobacter spp. recovery in seeded litter over 24 h: significantly more Campylobacter spp. was recovered at 0 or 3 h post-seeding than at 6 and 24 h post-seeding, indicating that the pathogen can survive to detectable levels for at least 3 h in this environment.4. In the second phase, three groups of 10 broiler chickens (negative for Campylobacter spp. prior to exposure) were exposed at 21 days of age to one of three different Campylobacter jejuni and C. coli mixes (A, B, C), using the method above. At 28 days of age, birds were euthanised by overdose of barbiturate or cervical dislocation, and livers and caeca removed for Campylobacter spp. assessment.5. All liver and 28/30 caeca samples tested positive for Campylobacter spp., with mix A and C giving higher counts in the caeca than mix B. The method of euthanasia did not affect Campylobacter spp. counts.6. In conclusion, a successful method for reliably colonising broiler chickens with Campylobacter spp. has been developed which negates the need for gavaging and is more representative of how contamination occurs in the field. 相似文献
990.
A. Lecoindre D. Saade P. Barthez J. L. Cadoré P. Lecoindre 《The Journal of small animal practice》2018,59(5):311-314
A one‐year‐old female cocker spaniel presented with a 6‐month history of persistent diarrhoea. Abdominal ultrasonographic examination revealed mild diffuse thickening of the intestinal wall coupled with mesenteric lymphadenopathy. A connection between the duodenum and the colon was observed during an endoscopic procedure and confirmed by computed tomography. Surgical resection of the communication allowed remission of the diarrhoea. Histology showed a normal duodenal epithelium and muscular layer. A duodenocolic fistula is an abnormal connection within the digestive tract, which in humans is usually considered a complication of a local pathological condition. Due to the absence of a predisposing cause and, in view of the dog's age and histological results, a congenital origin was suspected. 相似文献