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Prevalence and Heritability of Symptomatic Syringomyelia in Cavalier King Charles Spaniels and Long‐term Outcome in Symptomatic and Asymptomatic Littermates 下载免费PDF全文
M.S. Thfner C.L. Stougaard U. Westrup A.A. Madry C.S. Knudsen H. Berg C.S.E. Jensen R.M.L. Handby H. Gredal M. Fredholm M. Berendt 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(1):243-250
Background
Syringomyelia (SM) is common in the Cavalier King Charles Spaniel (CKCS). Dogs with syringes express clinical signs or might be clinically silent.Objectives
To investigate the prevalence and heritability of symptomatic SM, the association between clinical signs and magnetic resonance imaging (MRI) findings, and long‐term outcome.Animals
All CKCS registered in the Danish Kennel Club in 2001 (n = 240).Methods
A cross‐sectional questionnaire‐based prevalence study validated by telephone interviews and clinically investigated clinical signs of SM. Dogs were 6 years at the time of investigation. A prospective observational litter study including clinical investigations, MRI and 5‐year follow‐up of symptomatic and asymptomatic siblings. Heritability was estimated based on the scale of liability in the study population and litter cohort.Results
The cross‐sectional study estimated a prevalence of symptomatic SM at 15.4% in the population. Thirteen symptomatic and 9 asymptomatic siblings participated in the litter study. Spinal cord syringes were confirmed in 21 of 22 littermates (95%). Syrinx diameter and mean syrinx : spinal cord ratio were significantly correlated with clinical signs (P < .01). Estimated heritability of symptomatic SM was 0.81. Symptomatic SM motivated euthanasia in 20%. Dogs with syringes, which expressed no clinical signs at the age of 6, remained asymptomatic in 14/15 cases (93%).Conclusions and Clinical Importance
The prevalence of symptomatic SM is high and genetics have a high impact on clinical disease expression. Further investigations of factors influencing the outbreak threshold of clinical signs of SM are desirable. 相似文献43.
Low‐Field MRI and Multislice CT for the Detection of Cerebellar (Foramen Magnum) Herniation in Cavalier King Charles Spaniels 下载免费PDF全文
K. Kromhout H. van Bree B.J.G. Broeckx S. Bhatti L. Van Ham I. Polis I. Gielen 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(1):238-242
Background
Cavalier King Charles Spaniels (CKCS) have a high prevalence of Chiari‐like malformation (CM). Herniation of the cerebellum into the foramen magnum is a key diagnostic feature for CM. Midsagittal MR images are the preferred technique for visualizing cerebellar herniation (CH).Objective
To investigate whether CT can be used to diagnose CH.Animals
Fifteen client‐owned CKCS dogs referred for investigation of the brain and cranial cervical spine on MRI and CT.Methods
Two reviewers retrospectively analyzed midsagittal T1WSE and T2WSE MR images and midsagittal pre‐ and postcontrast 2D multiplanar reformatted CT images from each dog for the presence of CH. And, if present, the length (mm, CHL) of the herniation was measured. The results were analyzed statistically.Results
There was no significant difference between the different observers and techniques for the detection of CH and measurement of CHL. Overall, the CHL was longer on the CT images.Conclusion and Clinical Importance
Both techniques are useful for detecting CH and measuring CHL. Because CHL does not have a known direct impact on the clinical presentation of CM, CT can be used as a diagnostic tool in a routine clinical practice for CM in CKCS when MRI is not available. We emphasize that MRI is the standard screening technique in CKCS for breeding purposes to detect the presence of CM and SM and, at the current time, CT cannot replace MRI. 相似文献44.
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为探讨芒果感染畸形病过程中顶芽内糖含量及其相关酶的变化规律,以凯特芒为试验材料,测定了接种病菌(Fusarium mangiferae)后顶芽内光合色素、糖类和纤维素含量及蔗糖代谢相关酶的变化趋势,并对糖含量变化与病害发生的关系进行了分析。结果表明:接种病菌后,芒果顶芽内光合色素含量、可溶性总糖、还原性糖、蔗糖和葡萄糖的含量均先上升后下降,而淀粉和纤维素含量随着接种时间的延长而不断降低;接种病菌对芒果顶芽内酸性转化酶活性无明显影响;中性转化酶和蔗糖合成酶(分解方向)随着处理时间的延长活性不断上升。蔗糖合成酶(合成方向)呈现先上升后下降的趋势。蔗糖磷酸合成酶的活性在接种病菌30 d后不断下降。由此推断,F. mangiferae的侵染对芒果体内糖代谢具有明显的影响,糖代谢失衡可能是芒果对病菌侵染的直接反应。 相似文献
46.
We report a case of a layer hen (Gallus gallus forma domestica) with deviation in the morphology of the caecum, and unique opportunity to investigate the digestive performance of the animal compared with normal hens. In a study investigating digestive and reproductive performance, an atypical caecal arrangement was found in a hen that was unremarkable in regards to body mass, digestive performance and egg productivity in comparison to other hens fed a similar diet. Examination of the gastrointestinal tract revealed a singular tubular outgrowth from the ileo‐caecal junction, rather than the typical paired outgrowths. The single caecal duct bifurcated into two separate blind‐ended sacs. Similar caecal deviations have been described in adult and juveniles, but no indications of animal performance were reported in these cases. We conclude that if the presence of an abnormal caecal arrangement reduces digestive abilities they were not obvious, and some compensatory mechanism/s may exist. Alternatively, the abnormal caecal arrangement of our hen might function adequately, such that no compensation in feed intakes or reduced egg productivity was required or observed. 相似文献
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Congenital hypoplasia of the dorsal colon in a Quarter Horse filly with chronic,intermittent colic 下载免费PDF全文
K. A. Robinson S. T. Manning S. M. Barber B. K. Wobeser K. L. Lohmann 《Equine Veterinary Education》2017,29(5):270-273
Congenital colonic anomalies are rare in the horse and, to the authors' knowledge, no cases have been reported that include measurements of each segment of the large colon to confirm which section is abnormal. This case report describes chronic, intermittent colic in a Quarter Horse filly that had been attributed to chronic idiopathic hepatitis prior to an exploratory laparotomy. A colonic anomaly discovered at surgery became the primary differential for aetiology of the intermittent colic. Euthanasia of the filly and necropsy allowed further examination of the anomaly, where it was determined that the dorsal colon was short compared to the ventral large colon. In addition, the diagnosis of chronic idiopathic hepatitis was confirmed. 相似文献
50.