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101.
Effect of tibial tuberosity advancement (TTA) on the patellar ligament has not been described. Our purpose was to evaluate the patellar ligament radiographically and ultrasonographically before and after a TTA. Twenty‐one stifles (20 dogs) were evaluated preoperatively (T0), and at six (n=18) (T1) and 16 weeks (n=17) (T2) postTTA. Radiographically, proximal and distal thickness of the patellar ligament was assessed and a ratio to the total length of the ligament was calculated to compensate for the magnification. Ultrasound evaluation included measurements of the transverse thickness and cross‐sectional area at three different levels, as well as a subjective score of ligament changes. In comparison with T0, all radiographic and ultrasonographic measurements increased significantly, 6 weeks postoperatively (P≤0.04), and did not change 16 weeks postoperatively compared with T1. The subjective score worsened significantly from T0 to T1 and T0 to T2 (P<0.0001), and improved significantly from T1 to T2 (P=0.02). Larger cage size was associated with a more severe increase in radiographic proximal thickness to total length ratio and ultrasonographic middle transverse area at both follow‐up examinations (P0.02). Dogs in which arthrotomy was not performed appeared to have ultrasonographically less changes. In conclusion, patellar desmopathy was a common postoperative sequel to TTA. Surgical trauma, arthrotomy, perfusion injury, complete vs. partial cranial cruciate ligament rupture, larger tibial advancement, postoperative activity or altered insertion angle of the patellar ligament at the tibial tuberosity are suggested causes, that should be elucidated in a larger study cohort.  相似文献   
102.
Our goal was to investigate the effect of contrast medium injection duration on pulmonary artery peak enhancement and time to peak enhancement. Fourteen dogs were allocated into one of seven predefined weight categories, each category contained two dogs. Dogs in each weight category were assigned to group A or B. Animals in each group received a different contrast medium injection protocol. In group A, a fixed injection rate of 5 ml/s was used. In group B, the contrast injection rate was calculated as follows: flow rate=contrast volume/scan duration+10 s. Time to peak enhancement and peak enhancement of the main left and right pulmonary arteries were measured on single‐level, dynamic CT images for a fixed time of 30 s. Rank correlation (Spearman's) coefficients between injection duration and time to peak enhancement and between body weight and peak enhancement were calculated. For group A, there was a significant negative correlation between peak enhancement and weight (r=?0.94; P=0.005), while for group B, there was no significant correlation (r=?0.64 and P=0.18). There was a significant correlation between time to peak enhancement and injection duration in both groups (group A: r=0.99; P=0.006 and group B: r=0.85; P=0.02). In conclusion, injection duration is a key feature in a CT angiography injection protocol. A protocol with an injection duration adjusted to the scan duration seems to be particularly suitable for veterinary applications where a population with great weight variability is studied.  相似文献   
103.
The objective of this prospective observational cohort study in free-ranging female white-tailed deer (Odocoileus virginianus) was to compare the physiologic effects of two methods of anesthetic drug administration: hand-injection in Clover traps and remote injection by dart after ground-stalking. Six trapped and 14 darted female deer were injected with a median (minimum, maximum) of 590 microg/kg butorphanol (401, 1070 microg/kg), plus 235 microg/kg medetomidine (160, 429 microg/kg) intramuscularly. In the trap, the deer struggled when approached and were restrained for injection. Darted deer sprinted away after injection. Once immobilized, deer were transported to a veterinary hospital where blood was collected and vital signs were measured on admission. Admission data from a subset of deer in which measurements were taken within 40 min of trapping (n = 6) or darting (n = 5) were analyzed. After salpingectomy under isoflurane and while still anesthetized, another blood sample was collected from all 20 deer. Body weight and immobilization drug doses were not different between groups. On admission, most deer from both groups were hypoxemic, although the darted deer were significantly more hypoxemic. The median rectal temperature in trapped deer was higher than in darted deer, and temperatures higher than 39 degrees C only occurred in trapped deer. The median heart rate in trapped deer was more than twice that in darted deer. Trapped deer had lower median pH and base excess; in trapped deer, the median plasma lactate concentration was more than fivefold higher than in darted deer. After surgery, the median serum creatine kinase concentration was nearly 10-fold higher in trapped deer, and the median cardiac troponin I concentration was higher in trapped deer but undetectable in 10 of 14 darted deer. The white-tailed deer immobilized by hand-injection in Clover traps experienced more severe physiologic perturbations than deer remotely injected by dart after ground-stalking. These perturbations might be sufficient to cause myocardial damage.  相似文献   
104.
A granddaughter design containing five half-sib families from German Holstein–Friesian cattle was subjected to QTL analysis starting from the hypothesis of the existence of more than one QTL on chromosome BTA 6 affecting milk yield, fat yield, protein yield and content of fat and protein. The marker map consisted of 16 microsatellite markers with marker heterozygosity varying from 0.44 to 0.94. Two statistical methods were used: least squares (LS) and residual maximum likelihood (REML) allowing for two QTL simultaneously. The test statistics were calculated in steps of one cM along the chromosome. Significant QTL at the chromosome-wise 5% level according to the permutation test critical value were detected mainly in single families. The results were in conformance with the findings of several previous studies with approximate positions of putative QTL at 49 cM for milk yield, at 70 cM for fat and protein yield, and at 46 cM for protein content. Further QTL positions were suggested mostly for yield traits and protein content in the area of the casein gene cluster at 90…95 cM. The results of the two-QTL model analyses when using LS led to family specific inferences of a second QTL for fat yield and content of protein and fat, partly supported by the epistasis model.  相似文献   
105.
OBJECTIVE: To determine whether dorsolateral subluxation (DLS) scores in young dogs could be used to reliably predict which dogs would develop evidence of hip osteoarthritis and whether DLS scores measured at various ages correlated with each other. ANIMALS: 129 Labrador Retrievers, Greyhounds, and Labrador Retriever-Greyhound crossbreds. PROCEDURES: DLS scores were measured on radiographs taken at 4, 8, and 12 months of age and at necropsy (8 to 36 months of age). At necropsy, the hip joints were examined macroscopically and a score assigned for degree of cartilage degeneration. RESULTS: DLS scores at 4 (n = 35, r(s) = -0.62), 8 (n = 106, r(s) = -0.54), and 12 (n = 15, r(s) = -0.87) months of age were significantly correlated with cartilage degeneration scores, and DLS scores at 8 months of age were significantly correlated with scores obtained at the time of necropsy (n = 39, r(s) = 0.87). The DLS scores at 4 months of age were significantly different from scores at 8 months of age, but scores did not differ significantly thereafter. Likelihood ratios for cartilage lesions for low (< 45%), intermediate (> or = 45 but < or = 55%), and high (> 55%) DLS scores at 8 months of age were 8.0, 2.6, and 0.2, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that DLS score at 8 months of age was a reasonable, albeit imperfect, predictor of the condition of the hip joint cartilage at necropsy. Thus, the DLS method might be useful for early identification of dogs with hip dysplasia.  相似文献   
106.
107.
Measurement of heart-girth (chest circumference) is commonly used to estimate dairy heifer body weight from previously derived equations or tables. In this experiment, variability of heart-girth measurements as they are taken in the field was analyzed to determine the standard deviation within a group of 26 Holstein heifers of various ages weighing 42–590 kg. Standard deviations were 2.19 cm among 26 observers and 2.74 cm within any one observer. Repeatability between two heart-girth measurements by an individual observer on the same animal using a blind heart-girth tape was >0.99. Correlation coefficients between two measurements by different observers using blind measuring tapes on the same animal also were >0.99, with 99% of total differences due to observer and heifer, indicating very little random variation. A second part of this study was the validation of the most recently derived equation to calculate body weight from heart-girth. The equation was validated with data sets from universities across the United States and field data collected specifically for this study. Experimental and field data comprised of heart-girth and body weight measurements upheld the previously derived equation and support its continued use. These results allow more precise interpretation of heart-girth data collected from field studies with Holstein dairy heifers and provide more complete validation of existing body weight-prediction equations.  相似文献   
108.
Objective To measure the effects of dobutamine infusion on fetal oxygenation during isoflurane anaesthesia in pregnant ewes. Study design Prospective randomized experimental study. Animals Seven clinically normal adult pregnant Rambouillet‐Dorset cross ewes with fetuses of 117–122 days gestational age. Methods The ewes were anaesthetized with ketamine (2 mg kg?1) IM, and isoflurane (FE′ISO 2.0%) in oxygen. After instrumentation and stabilization, dobutamine was infused at 4 µg kg?1minute?1 for 60 minutes and 10 µg kg?1minute?1 for 60 minutes in random order, separated by a 20‐minute washout period. Catheters were placed in the maternal and fetal carotid arteries; these were used for continuous blood pressure measurement and intermittent blood sampling. Results Maternal mean systemic carotid arterial pressure was 60 mm Hg prior to dobutamine infusion. After 5 minutes of dobutamine infusion, fetal oxygen saturation increased (p < 0.05) from 0.62 (0.17–0.71, minimum–maximum) to 0.72 (0.28–0.78) at a dose of 4 µg kg?1minute?1 and to 0.70 (0.20–0.73) at a dose of 10 µg kg?1minute?1. These increases were maintained during the infusion and were not significantly different between doses. Maternal oxygen saturation remained constant at 1.0 before and during all infusions. Although maternal heart rate and blood pressure increased (p < 0.05) by 90% and 25%, respectively, with dobutamine, this stimulant effect was not evident in the corresponding fetal variables. Maternal haemoglobin concentration increased 30% (p < 0.05) with each infusion. Conclusions Dobutamine at 4 µg kg?1minute?1 increases fetal oxygenation that is not improved by a dose of 10 µg kg?1minute?1. This increase is largely due to an increase in maternal haemoglobin concentration that, in turn, increases oxygen delivery to the placenta. Clinical relevance The use of dobutamine to treat hypotension in pregnant sheep during isoflurane anaesthesia improves fetal oxygenation. This may be true in other species.  相似文献   
109.
Objective To evaluate the effectiveness of two insulin doses to maintain an acceptable range of blood glucose concentrations (70–200 mg dL?1) in the peri‐operative period in diabetic dogs. Animals Twenty‐four diabetic dogs with a median weight of 20.6 kg and a median age of 8 years old. Methods The dogs were randomly assigned to receive either 25 or 100% of their normal insulin dose subcutaneously on the morning of surgery. The anesthetic and feeding protocols were standardized. On the day before surgery, venous blood was collected for measurement of β‐hydroxybutyrate, cholesterol, glucose, glycosylated hemoglobin, hematocrit, total plasma protein and urea nitrogen. On the day of surgery, blood glucose concentrations were measured prior to anesthesia, prior to the start of surgery, 1 and 2 hours after beginning of surgery, 1 hour after extubation, at 16 : 00 hours and at 20 : 00 hours. β‐hydroxybutyrate concentrations were measured at 20 : 00 hours that day. At 08 : 00 hours the following day, β‐hydroxybutyrate and glucose concentrations were measured. The significance of differences between groups was tested with Wilcoxon's two‐tailed rank‐sum test, Chi‐square test and Fisher's exact test. Results There were no differences in insulin treatments, clinical signs, concurrent diseases and most clinicopathological parameters between the two groups of dogs at entry to the study. The 25% dose group had blood glucose values of 296 (102–601) mg dL?1 at 16 : 00 hours and 429 (97–595) mg dL?1 at 20 : 00 hours on the day of surgery. The 100% insulin dose group had lower corresponding values of 130 (55–375) mg dL?1 (p = 0.04) and 185 (51–440) mg dL?1 (p = 0.004). No other differences (p < 0.05) were detected between the two groups. Conclusions The administration of a full dose of insulin is only marginally advantageous for reducing glucose to normal (70–120 mg dL?1) after anesthesia but neither dose consistently induced glycemic values in an acceptable range (70–200 mg dL?1) or normoketonemia. Clinical relevance Blood glucose should be measured immediately before anesthesia and periodically throughout the peri‐operative period in all diabetic dogs because presurgical subcutaneous administration of 25 or 100% of the normal insulin dose resulted in unpredictable blood glucose concentrations.  相似文献   
110.
Our purpose was to assess the accuracy and precision of a point of care hemoglobinometer (HemoCue‐B hemoglobin photometer) for measuring hemoglobin concentration in horse blood. Samples of jugular venous blood from 12 healthy adult horses were collected in EDTA. In order to test the device over a wide range of values, each sample was divided into nine aliquots, and autologous plasma was added or removed from the aliquots to produce blood with PCV values that approximated 5, 10, 20, 30, 40, 50, 60, 70, and 80%, respectively. The aliquots were rocked to ensure mixing of plasma and cells. Then hemoglobin by HemoCue‐B (HbHQ) and hemoglobin by the cyanmethemoglobin method (HbCY) were measured on each aliquot. The PCV of each aliquot was also measured and this value was used for subsequent analyses. To test repeatability, hemoglobin was measured twice by the HemoCue‐B on approximately 40% samples. Samples with HbHQ >25.4 g dL?1 required dilution prior to analysis. HbCY ranged from 1.6 to 33.4 g dL?1. After regression, HbCY = ?0.16 + 1.04 HbHQ (n = 101; r2 = 99.6%). By inspection of a modified Bland‐Altman plot, HbHQ values <16 g dL?1 closely approximated HbCY; however, at greater values, HbHQ underestimated HbCY by as much as 3.2 g dL?1. The difference between repeated measurements with the HemoCue‐B was 0.02 ± 0.16 g dL?1 (mean ± SD; n = 10) and nonsignificant. After regression, PCV = ?0.76 + 2.78 HbHQ (n = 101; r2 = 99.4%). We conclude that HemoCue‐B can be used to measure hemoglobin concentration in horse blood, and that it is accurate when hemoglobin is <16 g dL?1. PCV can be estimated by multiplying HbHQ by 2.8 and then subtracting 0.8.  相似文献   
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