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Large-colon torsion is a common cause of colic in horses and has a worse prognosis and higher cost than other causes of surgical colic of the large colon. During large-colon torsion, the colon wall becomes thick due to vascular occlusion. Therefore, we hypothesized that detecting increased colon wall thickness during ultrasonography would be an accurate preoperative test for large-colon torsion. The sample population consisted of 42 horses that were admitted for surgical treatment of colic localized to the large colon. The diagnosis was confirmed at surgery or necropsy examination. Twelve (29%) of these horses were diagnosed with large-colon torsion. Duplicate ultrasonographic measurements of colon wall thickness were made at six abdominal locations and an average measurement was calculated. For four of these six sites, a significant difference (P < 0.005) was detected between horses with and without large-colon torsion. All four tests were moderately sensitive and highly specific for diagnosing large-colon torsion using five decision criteria. Using a ventral abdominal window, a colon wall thickness > or = 9 mm accurately predicted large-colon torsion in eight of the 12 horses (sensitivity, 67%; confidence interval [CI], 36-98%) and correctly predicted that large-colon torsion was absent in 28/28 horses (specificity 100%; CI, 98-100%). Intraobserver repeatability was assessed by evaluating the difference between the first and second measurements obtained, which was < or = 2 mm. Therefore, detecting increased large-colon wall thickness during ultrasonography is a reproducible and accurate preoperative test for large-colon torsion in horses with surgical colic localized to the large colon.  相似文献   
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Anthelmintic resistance (AR) is a well-recognized challenge in farmed ruminants. The use of anthelmintics in combination is one of the strategies recommended to slow the rate of AR development. Two studies were undertaken in 2017 and 2019 to assess the efficacy of single-dose macrocyclic lactone (ML) anthelmintic and ML combination drenches. In total, 11 Faecal Egg Count Reduction Trials (FECRTs) were set up in 10 different beef herds, with results available from 10 of those FECRTs (9 herds). AR to a single ML anthelmintic was detected in all 9 herds, with resistance to Cooperia and Haemonchus spp on 9 farms, and resistance to Ostertagia and Trichostrongylus spp on 2 farms. In contrast, for the ML combination anthelmintics, all FECRTs resulted in efficacies of 99%–100%. The results suggest that cattle producers should strongly consider using combination drenches in their herds in preference to single actives.  相似文献   
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Greater depths of muscle are associated with better reproductive performance in ewe lambs, but, in adult ewes, reproductive performance also seems to vary with liveweight gain during the mating period. Therefore, in a large field study with Merino ewe lambs, we tested whether the relationships among eye muscle depth (EMD), fat depth (FAT) and reproductive performance depend on liveweight gain during the mating period. We selected lambs with a wide range in phenotypic values for depths of eye muscle (EMD) and fat (FAT) and assigned them to dietary treatments designed to achieve low (LOW, n = 244) or high (HIGH, n = 237) rates of liveweight gain during a 28‐day mating period. The LOW treatment maintained live weight, whereas the HIGH treatment gained 179 ± 3.8 g/day (p < 0.001). From those ewe lambs that attained puberty, first oestrus was detected at live weight 37.8 ± 0.2 kg and age 232 days. The proportion of ewes that attained puberty increased with EMD (p < 0.01). Ewes from the HIGH treatment were more fertile (pregnant ewes per 100 ewes exposed to rams) and had a higher reproductive rate (foetuses in utero per 100 ewes exposed to rams; p < 0.001) than those from the LOW treatment. Fertility and reproductive rate were positively correlated with weight gain during mating as well as live weight at the start of mating, FAT and EMD (p < 0.05 to <0.001). We conclude that faster growth, due to either extra nutrition during mating or higher phenotypic potential for fat and muscle, will increase reproductive performance in ewe lambs mated at 8 months of age.  相似文献   
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J. F. Innes  BVSc  PhD    M. Costello  MVB    F. J. Barr  MA  Vet.  MB    H. Rudorf  Dr. Med. Vet.    A. R. S. Barr  MA  Vet.  MB  PhD 《Veterinary radiology & ultrasound》2004,45(2):143-148
A radiographic scoring system for features of osteoarthritis of the canine stifle joint was devised. Intra- and inter-rater agreement was assessed by calculation of unweighted kappa statistics. "Global score," "effusion," "osteophytosis," and "intra-articular mineralization" were all features that had acceptable reliability, but "subchondral sclerosis" did not. The scoring system was used in a 13-month prospective study of the radiographic progression of osteoarthritis of the stifle joint, secondary to cranial cruciate ligament deficiency, in 58 dogs. In the index stifle joints all features were characterized by significant change over time, but osteophytosis had the greatest degree of change. In addition, 40% of contralateral joints showed progressive osteophytosis.  相似文献   
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The ultrasonographic findings in three small breed dogs with intracranial arachnoid cysts are described. Ultrasound images were obtained via the foramen magnum, temporal window and persistent bregmatic fontanelle (when possible). In transverse, dorsal and sagittal transcranial ultrasound images there was marked dilation of the lateral ventricles and a well-defined, oval to triangular-shaped anechoic area between the caudal aspect of the occipital lobes, dorsal to the midbrain, and rostral to the cerebellum. These findings were consistent with a diagnosis of concurrent hydrocephalus and an arachnoid cyst within the quadrigeminal cistern.  相似文献   
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Objective- The purpose of this study was to determine whether an endogenous benzodiazepine receptor ligand (EBZ) was present in the arterial and portal blood of dogs with congenital portosystemic shunts (CPSS).
Study Design- The presence or absence of an EBZ was determined by the collection of systemic and portal blood from dogs with CPSS.
Animals- Fifteen client-owned dogs with a confirmed CPSS. All dogs had historical signs compatible with hepatic encephalopathy. Eight healthy dogs were used as controls.
Methods- In all dogs, systemic blood samples were collected after they were anesthetized. Portal blood samples were collected intraoperatively. EBZ was measured by radioreceptor assay.
Results- In 10 of 15 dogs, the portal blood concentration of EBZ was significantly elevated compared with normal dogs (mean, 13.2 ±18.55 ng/mL). Five dogs had elevated systemic blood EBZ levels (mean, 8.2 ±16.08 ng/mL). Eleven of 15 dogs had a higher portal than systemic blood concentration of EBZ. In contrast, control dogs had extremely low EBZ concentrations detected in their portal blood (mean, 0.16 ±0.3 ng/mL) and systemic blood (0 ng/mL). The mean portal and systemic blood concentrations in dogs with CPSS were significantly greater than in control dogs ( P <.05).
Conclusions- Elevated blood levels of EBZ were found in dogs with CPSS. The portosystemic gradient noted in 11 dogs suggests the gastrointestinal tract as a possible source for the endogenous ligand.
Clinical Relevance- Generalized motor seizures have been reported in dogs after surgical correction of CPSS. If the presence of a CPSS results in stimulation of brain receptors for benzodiazepines, post-CPSS ligation seizures may result from a withdrawal of EBZ after ligation of the portosystemic shunt.  相似文献   
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