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911.
Natural and experimental astrovirus infection of cats 总被引:1,自引:0,他引:1
912.
H F Schryver D W Meakim J E Lowe J Williams L V Soderholm H F Hintz 《Equine veterinary journal》1987,19(4):280-287
The effect of level of protein intake on growth and calcium metabolism was studied in 24 foals. Starting at four months old, the foals were fed one of three diets containing all nutrients, with the exception of protein, at levels recommended by the United States National Research Council Subcommittee on Horse Nutrition for a 12 month period. The protein levels in the three diets were 9 per cent (low protein) 14 per cent (NRC recommended level) and 20 per cent (high protein). The foals fed the low protein diet were changed to the high protein diet after 140 days when they were nine months old. There were no significant differences in the rates of growth in weight, height, cannon circumference or in hoof growth and feed utilisation of the horses fed the 14 or the 20 per cent protein diets. However, growth, feed intake and feed utilisation by the foals fed the low (9 per cent) protein diet were significantly depressed. The average daily gains for the first 140 days for the 9, 14 and 20 per cent protein treatment groups were 64, 631 and 687 g in weight, 0.57, 0.83 and 0.87 mm in height and 0.04, 0.13 and 0.14 m in forecannon circumference, respectively. The average daily feed intakes for the 140 day period for the three groups were 2.7, 4.4 and 4.7 kg, respectively. After the change to the high protein diet the foals that had been fed the low protein diet maintained a higher rate of gain in bodyweight, height and cannon circumference, and utilised feed more efficiently than the other two groups throughout the second 140 days of the experiment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
913.
A 2-year-old female gyrfalcon (Falco rusticolus) was being used to hunt ducks in southeastern Wyoming during an outbreak of avian cholera in waterfowl and wild turkeys. While out overnight, the falcon consumed a bird. Within 24 hours the falcon was anorectic, and it was found dead approximately 48 hours following ingestion of wild prey. Gross and microscopic lesions were typical of avian cholera, and Pasteurella multocida serotype 1 was isolated from tissues of the falcon. 相似文献
914.
A severe outbreak of Emory milkvetch poisoning in cattle and sheep occurred near Roswell, New Mexico, in the spring of 1975. Mortality averaged 2% to 3% and morbidity averaged 15% to 20%. Emory milkvetch collected from the infested area contained miserotoxin measured as 5 to 9 mg of NO2/g of plant (dry weight). Chicks fed extracts of Emory milkvetch showed toxic signs when fed one dose as 300 mg of NO2/kg of body weight, and died within 5 to 8 hours when fed milkvetch as 400 mg of NO2/kg. A sheep fed Emory milkvetch for 7 days in the form of 38 mg of NO2/kg/day developed signs of nitro poisoning on the 7th day. Cattle were poisoned or died when fed Emory milkvetch as 12 to 20 mg of NO2/ig for several days. The toxic signs observed in the field and under experimental conditions were similar. 相似文献
915.
Tissue samples were taken from pregnant ewes and their 3-month fetuses 96 hours after intraruminal dosing of the ewes with tritiated choline. Starting 5 months before mating, one group of ewes had been given a manganese (Mn)-deficient ration and a second group had been given a Mn-supplemented (normal) ration. The results indicate that Mn depletion decreased the overall uptake of choline; the radioactivity of all tissues from the Mn-depleted group was lower than the radioactivity of the corresponding tissues from the group given a Mn-supplemented (normal) ration. The radioactivity of fetal tissues was also lower in the Mn-deficient group than it was in the Mn-supplemented group. Lower radioactivity concentrations were also observed in the whole plasma (sampled at various times after radioisotope dosing) and its lipid extract of Mn-depleted ewes than in the plasma and its lipid extract of Mn-supplemented ewes. There was no significant difference in the fatty acid composition of hepatic phosphatidyl choline between the two groups. However, the proportions of linoleic, stearic, and arachidonic acids were lower in fetal hepatic phosphatidyl choline than in maternal hepatic phosphatidyl choline. 相似文献
916.
Isolation of a herpsvirus from wild turkeys in Florida 总被引:1,自引:0,他引:1
917.
918.
Levamisole (LEV) was tested in four experiments to compare efficacy values against Ostertagia ostertagi when larval maturation was occurring (September), following inhibition and also when populations were expected to be largely adult (winter). A primary objective was to determine the importance of developing fourth-stage larvae (DL4) and inhibited, early fourth-stage larvae (EL4) in replacing adult worms lost through treatment and the effect of this on reduced efficacy against adult worms. Young crossbred beef calves ranging in weight from 150 to 230 kg were used in the first (September 1981), second (September 1983) and third experiments (January 1987). Jersey calves of 110 kg average weight were used in the fourth experiment (December 1988). Calves were randomized to groups according to weight and group sizes ranged from three to five calves. All parasite infections were naturally acquired, but a mixture of nematode third-stage larvae (L3) (22,500 per calf), including 20% Ostertagia ostertagi, was inoculated into Jersey calves of Experiment 4 following a 2 week exposure to natural infection. All LEV treatments were by subcutaneous injection at dosages of 6 and 8 mg kg-1. Treatment with ivermectin was used only in Experiment 3 as an efficacy reference. All calves were killed at 8-10 days after treatment. The efficacy of LEV against all developmental stages of Ostertagia ostertagi was consistently low in all experiments and a dose-dependent response was not evident. Large numbers of all Ostertagia ostertagi developmental stages were present in non-treated calves in both September experiments. Percent reduction of adults, DL4 and EL4 at the 6 mg kg-1 and 8 mg kg-1 dosages, respectively, were adults, 51.7 and 23.6 (1981), 8.7 and 51.3 (1983); DL4 40.3 and 13.2 (1981), 37.9 and 33.1 (1983); EL4, 19.6 and 0 (1981), 59.6 and 42.9 (1983). Smaller numbers of Ostertagia ostertagi were present in winter experiments and adult worms greatly outnumbered larval stages. Percent reductions of adults, DL4 and EL4, respectively, were (1987) LEV 6 mg kg-1, 40.2, 0 and 0; ivermectin 200 micrograms kg-1, 98.7, 97.7 and 100.0; (1988) LEV 6 mg kg-1, 62.4, 100.0 and 100.0; LEV 8 mg kg-1, 49.1 65.0 and 74.1. Too few larval stages were present in the latter experiment for valid efficacy values.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
919.
WALTER E. WEIRICH D.V.M. PH.D. WILLIAM E. BLEVINS D.V.M. M.S. 《Veterinary surgery : VS》1978,7(1):2-7
Twelve dogs and one cat were operated to close a ventricular septal defect. The method of patient selection, associated lesions, techniques used to correct the defect and significance to the total population of small animals with congenital lesions is discussed. Ten of 13 animals survived surgery. When indicated, this procedure can be safely performed to correct ventricular septal defect. 相似文献
920.
G Lust R J Todhunter H N Erb N L Dykes A J Williams N I Burton-Wurster J P Farese 《American journal of veterinary research》2001,62(11):1711-1715
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