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151.
152.
J. K. Dunn D. E. Bostock M. E. Herrtage K. F. Jackson M. J. Walker 《The Journal of small animal practice》1993,34(7):325-331
This paper describes the clinical and pathological features of 11 dogs with insulin-secreting tumours of the pancreas. All the dogs showed episodic weakness or collapse. The diagnosis was made on fasting plasma glucose and serum insulin concentrations, the insulimglucose ratio, and the results of an intravenous glucose tolerance test. Ten of the dogs had exploratory laparotomy, and partial pancreatectomy was performed in nine of the cases. One case was euthanased at surgery because of widespread metastases. The tumours were graded histologically and the results compared with the time to recurrence of clinical signs and postoperative survival time. Postoperative survival time for dogs which died or were euthanased as a direct result of tumour recurrence, and time to recurrence of clinical signs were calculated from actuarial survival curves. The median time to recurrence of clinical signs after surgery was 12 months (range from four to 16 months; mean time to recurrence of clinical signs 12 months). Two cases died of unrelated disease, without recurrence of hypoglycaemic signs. The median postoperative survival time was 14 months (range 10 to 33 months; mean survival time 15 months). There is a suggestion that tumours with a high mitotic count carried a worse prognosis. 相似文献
153.
Thirty foals of mixed breeding, from two consecutive years, were used in two 120-d experiments to evaluate the effects of supplemental feeding (creep feed) on growth in nursing foals. At 10 d postpartum, foals were randomly assigned either to a creep-fed group (CF) or an unsupplemented group (NCF). Initial measurements of body weight (BW), height at the withers (WH), third metatarsal length (MtIII) and third metacarpal length (McIII) were made at 10 d of age and at 30-d intervals thereafter. Medial and lateral cortical peak values for radiographic bone density, cortical width and cortical area at the midpoint of the third metacarpal were used to assess bone quality. Creep feed containing National Research Council (NRC, 1978) recommended levels for all nutrients was offered at 1.5% of BW per day. When compared with unsupplemented foals, supplemented foals had greater gains in BW (P less than .05), in WH (P less than .10) and in MtIII (P less than .05). Mean gains during the trial in BW, WH, MtIII and McIII for the CF foals were 133.3 kg, 22.8 cm, 2.1 cm and 1.9 cm and for the NCF foals were 117.6 kg, 21.2 cm, 1.5 cm and 1.9 cm, respectively. The mean value for the lateral cortical peak was slightly lower (P less than .10) for the CF foals. No differences (P greater than .10) were observed for the medial cortical peak, cortical width or cortical area of the third metacarpal. The results of this study indicate that a creep feeding program that supplies NRC-recommended nutrient levels can increase the rate of skeletal growth with little decrease in quality of bone. 相似文献
154.
Uterine irrigation was carried out in eight Welsh pony mares using 50 ml of chlorhexidine gluconate solution diluted to give active ingredient concentrations of 0.25 per cent to 2 per cent. Treatment was repeated up to twice in mares showing no adverse effects and irritancy of treatment judged on clinical symptoms and uterine biopsy. Results indicated the inadvisability of using a higher concentration than 0.25 per cent. Three daily applications of a diluted surgical scub solution containing 2 per cent chlorhexidine gluconate to the penis of an arab stallion failed to produce symptoms or irritation. An in vitro minimum inhibitory concentration test performed with the contagious equine metritis organism confirmed its high sensitivity to both chlorhexidine gluconate preparations. 相似文献
155.
Observations on the egg output resulting from continuous low level infections with Ostertagia circumcincta in lambs 总被引:1,自引:0,他引:1
Faecal egg counts were determined twice weekly for two groups of four-month-old worm free cross Suffolk lambs experimentally infected with 100 and 320 Ostertagia circumcincta larvae, five times per week for 20 weeks. The group mean egg count in both groups rose to a maximum of approximately 500 eggs per gram during weeks 12 to 14 and had fallen to less than half of that value at slaughter. There was no statistical difference in egg output between these two groups or between them and a comparable group of lambs receiving 4000 Ostertagia circumcincta larvae per day. No significant changes in live weight gain or serum pepsinogen levels were observed in the lambs given 100 and 320 larvae per day. 相似文献
156.
157.
This study concerns the vestigial metacarpal and metatarsal bones, so called splint bones. The soft tissues, which stabilize the splint bones were carefully examined. The palmar metacarpal/plantar metatarsal fascia, the metacarpal/metatarsal interosseous ligaments and the fibres, which exit distally from the splint bone, were examined in depth. Cadaveric distal limbs were collected from 5 slaughtered or euthanized horses. The legs were examined both, microscopically and macroscopically. The palmar metacarpal/plantar metatarsal fascia is a very stable structure, which connects the splint bone with its environment. The connection between splint and McIII/MtIII, established through the metacarpal/ metatarsal interosseous ligaments, showed impressive differences between specimens examined. Macroscopic examination of the soft tissue in the distal region showed a band structure, which originates from the distal end of the splint bone and extends in dorsal and distal direction towards the proximal sesamoid bone. 相似文献
158.
159.
AIM: To describe the reproductive performance of beef cow herds in New Zealand and to develop reference ranges for assessing the reproductive performance of individual herds from in-calf rates, that take into account variation in the length of mating periods. METHODS: Veterinary practices throughout New Zealand involved in beef cattle work were asked to collect reproductive data from seasonally calving beef cow herds mated in the spring of 2001 through to the end of summer of 2002. An estimate of conception rate (termed calculated conception rate: CCR) was determined for each herd, assuming that the conception rate was constant for each 21-day interval of the mating period. The algebraic relationship between CCR and in-calf rate at pregnancy testing was defined for mating periods of different durations and, therefore, given the in-calf rate and the duration of the mating period, a CCR could be determined for each herd. Expected pregnancy rates were recalculated from CCR data for a range of mating period durations to produce a look-up table for assessing herd reproductive performance. Reproductive data describing regional differences in in-calf rates and CCRs, bull:cow ratios, breed characteristics, start dates of mating and durations of mating periods were summarised. The effect of study variables in explaining CCRs was examined using a general linear model (GLM). RESULTS: Data were collected from 1,005 beef cow herds distributed throughout New Zealand. The median in-calf rate for all herds was 91%, the lower quartile was < or =88% and the upper quartile > or =94%. The mean CCR for herds with complete reproductive data (862) was 55% (SD 11), the lower quartile was < or =48% and upper quartile > or =61%. Median in-calf rates for 2-year-old heifers (mated at approximately 15 months of age), 3-year-old heifers (mated at approximately 27 months of age), and mixed-age cows were 90%, 91% and 92%, respectively. The study variables that accounted for significant variation in breeding group CCR in a multivariate GLM were 'region' (p<0.01) and 'date mating commenced' (<0.01). The adjusted R2 for the model was 0.055. CONCLUSIONS: The reproductive reference range produced provides veterinarians and herd managers with a quantitative method for assessing reproductive performance of beef cow herds compared with industry averages, from in-calf rates at the time of pregnancy testing and durations of mating periods. 相似文献
160.
Mehl ML Kyles AE Pollard R Jackson J Kass PH Griffey SM Gregory CR 《Veterinary surgery : VS》2005,34(2):114-119
OBJECTIVE: To compare 3 techniques for ureteroneocystostomy in cats. STUDY DESIGN: Experimental surgical study. ANIMALS: Fifteen adult cats. METHODS: Cats (15) had ureteroneocystostomy with ureteronephrectomy of the contralateral kidney: 5 cats had an intravesical mucosal apposition technique (modified Leadbetter-Politano; intravesical-MA group), 5 cats had extravesical ureteroneocystostomy (modified Lich Gregoir) using a simple continuous suture pattern (extravesical-SC group) and 5 cats had an extravesical technique using a simple interrupted suture pattern (extravesical-SI group). Renal function was evaluated by measuring serum creatinine concentration. Ultrasonographic assessment of the kidney and ureteroneocystostomy site was performed the day after surgery, twice weekly for 3 weeks and once weekly for the remainder of the study. Cats were euthanatized 50 days after surgery. The kidney and ureter removed at surgery, the remaining kidney, ureter, ureteroneocystostomy site, and bladder were examined histologically. RESULTS: Two extravesical-SC cats were euthanatized because of azotemia and uroabdomen, and 1 died acutely at day 4 for unknown reasons. In the intravesical-MA and extravesical-SI cats, the serum creatinine concentration increased after surgery, peaking at a mean (+/-SD) of 9.4+/-2.4 mg/dL and 4.9+/-3.3 mg/dL on day 3, and decreasing to 3.4+/-5.7 mg/dL and 1.5+/-0.4 mg/dL on day 7, respectively. The extravesical-SI technique was associated with consistently lower serum creatinine concentrations for the first week after surgery compared with the other techniques. The mean serum creatinine concentration was within the reference range in cats in the intravesical-MA and extravesical-SI groups by days 10 and 5, respectively. Renal pelvic dilatation occurred in all cats but resolved more rapidly in cats after extravesical techniques. There was no significant difference in serum creatinine concentrations or renal pelvic dilation between the intravesical-MA and extravesical-SI techniques. Bladder mass height at the anastomosis site was significantly larger and persisted for longer with intravesical-MA technique. CONCLUSION: An extravesical-SI technique is seemingly the choice for ureteroneocystostomy in cats with undilated ureters. Renal pelvic dilation on ultrasound examination should be expected after ureteroneocystostomy in cats. CLINICAL RELEVANCE: An extravesical ureteroneocystostomy technique using a simple interrupted pattern for anastomosis should be considered in cats undergoing renal transplantation. 相似文献