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101.
Female chicks from 6 pure lines of broiler breeders were obtained from international broiler breeder companies. The lines were from three female and two male lines and a relaxed selection line derived from one of the male lines (M2) and maintained without selection for 25 years (generations). Replicate groups from each line were reared in floor pens and fed ad libitum. An additional group of the M2 male line was feed restricted and housed in similar pens. Twenty birds from each group were photostimulated after housing them in individual cages at 14 weeks of age. Ovarian follicular dynamics and follicular sensitivity were determined after the onset of lay. Female lines had a greater proportion of atretic follicles and more groups of multiple follicles than male lines. Body weights, fatness and age at puberty were similar in male and female lines. The relaxed selection line had more abdominal fat than any of the selected lines and the ovary contained a similar number of normal yellow follicles as the selected male line. Feed restriction decreased body weight, the numbers of yellow follicles, multiple yellow follicles and the proportion of atretic yellow follicles, and increased the age at onset of lay. The response of ovarian follicles of three different sizes to exogenous gonadotrophin stimulation with PMSG was similar in small yellow follicles, 5 to 6 and 2 to 3 mm white follicles in a female line, a male line and its relaxed line fed ad libitum. The results suggest that the original lines from which modern male-line broiler stocks are derived had a relatively large number of yellow follicles and a high propensity for multiple ovulation at the onset of lay. Separate selection for different traits in male and female lines has not had a dramatic effect on ovarian function or sensitivity to gonadotrophin stimulation. 相似文献
102.
Heinritz CK Gilson SD Soderstrom MJ Robertson TA Gorman SC Boston RC 《Journal of the American Veterinary Medical Association》2005,227(3):435-440
OBJECTIVE: To determine the history, clinicopathologic findings, and results of surgery for effusive-constrictive pericarditis associated with Coccidioides immitis infection in dogs. DESIGN: Retrospective study. ANIMALS: 17 client-owned dogs that underwent a subtotal pericardectomy and epicardial excision. PROCEDURE: Hospital records from May 1999 to June 2003 were reviewed. Data collected included history, clinicopathologic findings, treatments, and outcome. Follow-up information was obtained via recheck examination and by use of standardized telephone interviews with referring veterinarians and owners. RESULTS: All dogs were of large breeds, and most were male (mean age, 4.66 years). Ten dogs had no prior history of C. immitis infection, and 7 dogs had chronic infection with C. immitis. Having a chronic C. immitis infection reduced the odds of survival, compared with no previous infection. All dogs had clinical signs of right-sided heart failure. All dogs had serum titers (range, 1:8 to 1:256) for antibodies against C. immitis prior to surgery, and titers were not significantly associated with outcome. Predominant echocardiographic findings were thickened pericardium, reduced right ventricular filling, and pleural or pericardial effusion. All dogs underwent a subtotal pericardectomy and epicardial excision and had fibrosing pyogranulomatous pericarditis in biopsy specimens obtained during surgery. The perioperative mortality rate was 23.5%, and the 2-year postdischarge survival rate was 82%. CONCLUSIONS AND CLINICAL RELEVANCE: Surgical treatment via subtotal pericardectomy and epicardial excision is successful at relieving right-sided heart failure in dogs with effusive-constrictive pericarditis secondary to C. immitis infection, but long-term treatment with antifungal agents may still be required. 相似文献
103.
Robertson SA Taylor PM Sear JW Keuhnel G 《Journal of veterinary pharmacology and therapeutics》2005,28(1):87-93
Data allowing rational use of analgesics in cats are limited. Pharmacokinetics and pharmacodynamics of fentanyl were studied in cats. Plasma fentanyl concentrations were measured using radioimmunoassay in a crossover study in six cats after 10 microg/kg (i.v.) or by application of fentanyl in pluronic lecithin organogel (PLO) to the inner ear pinna. On a separate occasion thermal thresholds were measured after i.v. fentanyl (10 microg/kg) or saline. Plasma fentanyl concentrations reached 4.7-8.31 ng/mL 2 min after i.v. administration and were undetectable after 95 min. Fentanyl was not detected in plasma at any time after PLO use. Thermal thresholds did not change following saline administration but were increased above baseline from 5 to 110 min after i.v. fentanyl. In this model a plasma concentration of >1.07 ng/mL was required to provide analgesia. Plasma concentrations were measured in additional cats after intranasal or oral dosing (2 microg/kg) and after 30 microg/kg in PLO gel. After oral and nasal dosing, Cmax values were 0.96 and 1.48 ng/mL at 5 and 2 min, respectively. Plasma fentanyl was not detected after application of the higher dose of fentanyl in PLO. 相似文献
104.
Effects of treatment with omeprazole or ranitidine on gastric squamous ulceration in racing Thoroughbreds 总被引:1,自引:0,他引:1
Lester GD Smith RL Robertson ID 《Journal of the American Veterinary Medical Association》2005,227(10):1636-1639
OBJECTIVE: To compare the effects of oral administration of omeprazole and ranitidine on gastric squamous ulceration in Thoroughbreds in race training. DESIGN: Modified crossover study. ANIMALS: 60 Thoroughbreds in race training with gastric squamous mucosal ulceration. PROCEDURE: Horses were randomly allocated into 3 groups. Group 1 received no treatment for 28 days followed by administration of omeprazole (4 mg/kg [1.8 mg/lb], PO, once daily) for 28 days; group 2 received omeprazole (4 mg/kg, PO, once daily) for 28 days followed by no treatment for 28 days; and group 3 received ranitidine (6.6 mg/kg [3.0 mg/lb], PO, q 8 h) for 28 days followed by administration of omeprazole (4 mg/kg, PO, once daily) for 28 days. Ulceration was assessed endoscopically at days 0, 28, 42, and 56. Lesions were scored from 0 (no ulceration) to 3 (severe ulceration). RESULTS: After the initial 28 days of treatment, the decrease in ulcer severity was significantly greater after omeprazole treatment than after ranitidine treatment. Ulcer severity decreased significantly in group 3 horses after 14 days of treatment with omeprazole. Discontinuation of omeprazole resulted in worsening of ulcer scores; however, ulcer scores at completion of the study were less than at day 0. Horses that received omeprazole after 28 days of ranitidine treatment had a further reduction in ulcer severity. CONCLUSIONS AND CLINICAL RELEVANCE: Omeprazole was more effective than ranitidine in healing gastric squamous ulcers in Thoroughbreds in race training. Improvement was detected by 14 days and persisted in most of the group 2 horses for at least 28 days after omeprazole treatment was discontinued. 相似文献
105.
106.
107.
108.
S.S. Sutherland D.V. Le Cras A.G. Robertson J.M. Johnston R.J. Evans 《Veterinary microbiology》1982,7(2):165-175
New and currently used serological procedures were evaluated using sera from cattle that were challenged with B. abortus S544 (S544) after vaccination with either B. abortus S19 (S19) or B. abortus 45/20 (S45/20) as calves or adults. In animals vaccinated with S19, titres to the indirect haemolysis test (IHLT) rose more slowly, declined more rapidly and involved fewer animals than did titres to the complement fixation test (CFT). In animals vaccinated with S45/20 the rough antigen complement fixation test (RCFT) showed persistent titres. At slaughter the IHLT and CFT were found to be more specific and more sensitive than the Rose Bengal Plate Test (RBPT) and Serum Agglutination Test (SAT) in the detection of cattle infected with B. abortus. 相似文献
109.
VERTICILLIUM WILT OF LUCERNE IN BRITAIN 总被引:3,自引:3,他引:0
110.
S R Hance J T Robertson 《Journal of the American Veterinary Medical Association》1992,200(8):1107-1110
A 5-year-old Thoroughbred gelding was examined because of a small axillary wound sustained 5 days earlier and had resulted in extensive subcutaneous emphysema. Three days after admission, the horse's respiratory rate had increased to 72 breaths/min, and the horse appeared anxious and distressed. Thoracic radiography revealed pneumomediastinum and severe bilateral pneumothorax. Tube thoracostomy was performed on both hemithoraxes. The drains were connected to one-way suction valves and suction devices to decompress the thorax. A nasopharyngeal catheter was inserted, and oxygen insufflation was started. Cross ties were placed on the horse to limit movement, and the wound was packed. The horse improved within 30 minutes after initiating treatment. The horse was released 15 days after the development of pneumothorax, at which time the pneumothorax had resolved, the wound was no longer open, and the subcutaneous emphysema had greatly decreased. Although subcutaneous emphysema is usually regarded as a temporary cosmetic disfigurement, it can lead to serious complications such as pneumothorax. This case demonstrates that subcutaneous emphysema can lead to a life-threatening pneumothorax if the pressure is great enough to migrate through the mediastinum and into the pleural cavity. Horses with subcutaneous emphysema should be kept in confinement and monitored for the development of pneumothorax. 相似文献