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391.
392.
Rectangular body wall specimens were extracted from 16 juvenile swine and 9 adult beagle hounds after euthanasia. The body wall specimen included the epidermis to parietal membrane, with falciform fat removed. Ten images of a reference phantom with known attenuation and 10 additional images of the phantom with the specimen placed between the transducer and phantom surface were collected with a 5-MHz ultrasound system and computer with frame grabber board. Mean pixel values were converted to relative echogenicities. Echogenicity versus depth yielded an estimate of attenuation. An unpaired t test was applied to compare reference attenuation values with and without body wall, and a Pearson correlation was applied to body wall parameters versus measured attenuation through body wall. Measured attenuation through body wall increased significantly in dogs (P = 0.0016) and swine (P < 0.0001) when compared with phantom material alone. Increased attenuation positively correlated to body wall thickness (r = 0.6442) and mean gray level within body wall (r = 0.5069) for swine but not in canine. The presence of body wall in images used for video signal analysis significantly increases the measured attenuation in a phantom. This increase does not correlate with a measurable body wall parameter in dogs.  相似文献   
393.
Quantitative thyroid scintigraphy using pertechnetate was performed in 43 cats with various T4 concentrations and compared to eight normal control cats. Quantitative parameters included percentage dose uptake of the radioisotope by the thyroid, thyroid:salivary ratio and rate of thyroid uptake. All cats were anesthetized for the scan, and images were obtained using both low-energy all purpose (LEAP) and pinhole collimators. All quantitative parameters were significantly correlated to the serum T4 concentration, but the best correlation was obtained using the 20-minute thyroid:salivary ratio using only the most intense of the two thyroid lobes. The thyroid:salivary ratio was a good predictor of the metabolic status of the thyroid.  相似文献   
394.
ULTRASOUND EVALUATION OF THE COXOFEMORAL JOINTS OF THE CANINE NEONATE   总被引:1,自引:0,他引:1  
The effectiveness of ultrasound in depicting the normal anatomy of the coxofemoral joint in puppies was evaluated. Ultrasound images were obtained from twenty Springer Spaniel puppies ranging from one day to twelve weeks of age. The anatomy of the hip joint could be identified up to eight weeks of age. By twelve weeks of age the degree of ossification prevented complete hip joint evaluation. Three different views were utilized. The longitudinal and dorsolateral views were the most useful. Motion of the femoral head within the acetabulum could be observed. Measurements of the acetabulum, femoral head and joint space could be obtained however these measurements were inconsistent. The technique appears to be useful for depicting the anatomy of the neonatal coxofemoral joint however, additional studies utilizing both normal and dysplastic puppies are recommended to determine if this examination will be useful in discriminating between normal and dysplastic puppies.  相似文献   
395.
Objective: To collate and describe emergency admissions to a large animal tertiary university referral hospital during a 12‐month period. Design: Prospective clinical study. Setting: Large animal tertiary university referral hospital. Animals: Large animal emergency patient admissions. Interventions: None. Measurements and main results: Information obtained from the medical record included the presenting complaint, clinical problem, admission time, duration of clinical signs before presentation, diagnostic procedures performed, therapies administered, and therapeutic procedures performed during the first 24 hours following admission, and survival to discharge. The most common category listed for the presenting complaint and clinical problem categories was gastrointestinal. Most emergency cases were admitted during the evening and in late spring, summer, and early fall. Most cases had a duration of clinical signs before presentation of >2 hours and ≤8 hours (27%) or >8 hours and ≤24 hours (29%). The most common diagnostic procedures performed during the first 24 hours were palpation per rectum, ultrasonographic examination, radiographs, and abdominocentesis. Antimicrobials, fluids, and nonsteroidal anti‐inflammatory drugs were the most common therapies administered. Approximately 25% of cases required surgery. An exploratory celiotomy was performed in approximately 15% of cases. Enterotomy, intestinal resection and anastomosis, cesarean section, or joint or sheath lavage was each performed in <5% of cases. Overall survival to discharge was 74%. Conclusions: Large animal emergency clinicians are required to have knowledge on a wide range of diseases and should be proficient at performing numerous procedures on an emergency basis. Gastrointestinal disease is the most common type of emergency and the diagnostic and therapeutic procedures performed during the first 24 hours following admission are a reflection of this type of case. Only 25% of cases required surgery. Additional research in the form of a multicenter study and surveying both private and university practitioners needs to be performed to further define the necessary skills for an ‘ideal’ large animal emergency clinician.  相似文献   
396.
Objective – To examine serum sodium, glucose, and tonicity in cats with diabetic ketosis. Design – Retrospective study. Setting – A university‐based referral hospital. Animals – Cats admitted to the ICU during the period 1998 to 2002 with a diagnosis of diabetic ketosis. Interventions – None. Routine clinical management of diabetes and associated conditions. Measurements – Serum biochemistry assessments. Main Results – Abnormalities of glucose, sodium and serum tonicity (ST) were common in the study group. Serum sodium but not glucose correlated closely with ST. A subset of cats treated with intravenous insulin and an isotonic sodium‐containing solution for 72 hours showed a significant decrease in glucose from admission values at 48 and 72 hours (but not at 24 hours). Serum sodium, potassium, and ST were not significantly different from admission values at any time over the 72‐hour period. However, the relative contribution of individual osmolytes varied over the course of treatment. Although glucose decreased >120% from admission values over the 72‐hour treatment period, the approximately 5% rise in serum sodium that occurred offset the osmotic effect of falling glucose and the overall ST change was <3%. Conclusions – The incidence of osmotic‐mediated neurologic complications during treatment of cats with diabetic ketosis is low in part because the minimal fluctuation in ST during treatment likely prevents the development of osmotic gradients between serum and central nervous system tissues. The use of isotonic sodium‐containing fluids in the treatment of feline diabetes acts to minimize large osmotic shifts by adding sodium to the serum compartment as the glucose concentration falls.  相似文献   
397.
The effect of different organic acids in diets of entire male pigs on the concentration of skatole in colon, plasma, and adipose tissue and on the composition of the microbiota in the gastrointestinal tract was evaluated. Entire male pigs (n = 60) of sows inseminated with boars disposition for high skatole levels (31.7 and 113.2 kg initial and final body weight, respectively) were fed either control, 1.0% formic acid, 0.85 % benzoic acid, 0.85% sorbic acid, 1.2% fat coated Ca-butyrate, or 1.5% fat and inulin coated Ca-butyrate diets. All levels of organic acids corresponded to 0.85% of pure acid. Digesta samples from colon descendens were analyzed for skatole, indole, and organic acids. Digesta samples for microbiological examinations were taken from proximal jejunum, colon descendens, and rectum. There were no differences in levels of skatole, indole, or organic acid levels in colon descendens among pigs fed organic acid supplemented diets and control diet. Plasma skatole levels were significantly reduced in pigs fed diets containing formic acid or benzoic acid compared with the control, but supplementing diets with organic acids did not affect skatole levels in adipose tissue. Pigs fed organic acids had significantly lower levels of coliforms, enterococci, and lactic acid producing bacteria (LAB) in all sampling sites of the gastro-intestinal tract. Pigs fed 1.5% fat and inulin coated Ca-butyrate had less reduction in the number of coliforms and LAB in the small intestine compared with pigs fed formic, benzoic and sorbic acid. Formic acid had a stronger antibacterial effect on coliforms than benzoic or sorbic acids in the small intestine. Pigs fed diets containing formic acid, benzoic acid, or sorbic acid had significantly higher average daily gain and better feed conversion ratio (FCR) than the control pigs during the grower phase, and tended to improve FCR during the overall period. The inclusion of fat coated Ca-butyrate or fat and inulin coated Ca-butyrate had no effect on growth performance of the pigs. In conclusion, supplementing diets with different organic acids reduced number of coliforms, enterococci, and LAB in the gastrointestinal tract, but did not affect skatole levels in colon or adipose tissue of entire male pigs.  相似文献   
398.
The reproductive cycle of the domestic dog features a long period of relative ovarian inactivity or anestrus. The mechanism of anestrous termination/oestrous resumption is not yet fully understood, which presents a challenge to the development of oestrous induction protocols. In this study, we assess the possibility that anti‐Müllerian hormone (AMH) might play a role in this transition by characterizing its patterns of expression in the circulation during the transition from anestrus to oestrous and in all stages of ovarian follicular growth. Serum samples from five beagles (2.0–4.5 years) were collected three times per week at least 30 days prior to the onset of oestrous and assessed for AMH concentrations. Serum AMH concentration increased significantly during the transition from anestrus to proestrus and then declined back to the anestrous baseline beginning on day ?4 before the luteinizing hormone surge, which was determined by changes in serum progesterone concentrations. Cortical sections of ovaries from females undergoing routine ovariohysterectomy (aged 8 months–5 years, n = 4) were evaluated for AMH by immunohistochemistry. Pre‐antral and small antral follicles were most strongly immunoreactive for AMH. These data suggest that the increase in the number of antral follicles is associated with the rise in serum AMH as the anestrous period comes to an end. The rise in AMH might be useful in predicting the onset of oestrus and therefore assist with the optimization of oestrous induction protocols and possibly other assisted reproductive technologies.  相似文献   
399.
YAN LU  MD    BRETT NEMKE  BS    DOUGLAS M. LORANG  PhD    ROEL TRIP  MD    HIROHITO KOBAYASHI  MS    MARK D. MARKEL  DVM  PhD  Diplomate ACVS 《Veterinary surgery : VS》2009,38(4):467-476
Objectives— To compare bone healing of tibial osteotomy repaired with Nitinol wire braid and hardened steel rods (Braid system) and polymethylmethacrylate bone cement with an interlocking intramedullary (IM) nail fixation in an ovine model.
Study Design— In vitro and in vivo experimental study.
Animals— Adult female sheep (n=22).
Methods— Using sheep tibia, a middiaphyseal transverse osteotomy was performed in the right tibia, which were then randomly assigned to the Braid system group or IM nail group (n=5). The left tibia were used as controls. The torsional properties of tibial constructs were compared. The study was repeated in vivo in 12 sheep and mechanical properties and bone healing were evaluated at 12 weeks.
Results— In vitro, there was no significant difference in torsional stiffness between the groups. In vivo, operative time for the Braid system group was significantly shorter than the IM nail group. At 12 weeks, there were no significant differences in maximum torque and torsional stiffness between IM nail and Braid system groups nor were there significant radiographic or histologic differences between the groups.
Conclusions— The Braid system might decrease operative time for repair of transverse middiaphyseal tibial fractures and result in similar bone healing at 12 weeks after surgery compared with an interlocking IM nail repair.
Clinical Relevance— A Nitinol Braid system may be a treatment option for transverse midshaft tibial fractures.  相似文献   
400.
Nutrition is a critical component of equine health. Horse owners' knowledge of nutrition is likely to affect their feeding practices. The aim of this study was to survey feeding practices, dietary supplement use, and knowledge about equine nutrition in New England by surveying a subpopulation of horse owners (67/337 or 19.8%) who brought their horses to the Large Animal Hospital at the Cummings School of Veterinary Medicine at Tufts University between July and September 2008. All owners reported feeding hay, with the majority feeding grass or timothy hay. Most owners (96%) reported feeding a concentrate in addition to hay. Approximately 84% of owners reported including at least one dietary supplement in their horse's daily feeding. The most commonly used supplements were chondroprotectives, electrolytes, and multivitamins. Survey questions designed to assess the owner's knowledge of nutrition suggested that many owners may not have a basic understanding of principles of equine nutrition; less than 50% knew the daily water and hay requirements for a horse, and 69% lacked knowledge about the proper use of concentrates in a diet. Most of the surveyed owners consulted multiple sources of information concerning equine nutrition, including veterinarians (n = 36), trainers (n = 27), feed stores (n = 10), and the internet (n = 7). Although the major source of information was the veterinarian, it appears that the communication between horse owners and their veterinarian about optimal feeding practices could be enhanced. This survey demonstrated areas in the veterinarian–client dialog that need to be addressed when evaluating the health and well-being of the horse.  相似文献   
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