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61.
The helminths of 25 kudu, Tragelaphus strepsiceros, from 3 localities in the eastern Cape Province were collected, counted and identified. The majority of kudu harboured no worms, and the burdens of those infected were small. A race of Cooperia rotundispiculum, a Dictyocaulus sp., a Haemonchus sp., Nematodirus helvetianus and Ostertagia ostertagi were recovered. Two parasites, Nematodirus helvetianus and Ostertagia ostertagi can be added to the list of helminth parasites of kudu in South Africa. 相似文献
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Serum neutralizing antibody titers in dairy cattle administered an inactivated vesicular stomatitis virus vaccine 总被引:1,自引:0,他引:1
M A Gearhart P A Webb A P Knight M D Salman J A Smith G A Erickson 《Journal of the American Veterinary Medical Association》1987,191(7):819-822
Two doses of a formalin-killed, cell culture-derived vesicular stomatitis virus (vsv)-New Jersey serotype vaccine were administered intramuscularly, 30 days apart, to all lactating and nonlactating cows in a 350-cow dairy herd. Serum specimens were obtained serially from 96 cows before vaccination and at 30, 52 and 80 days after vaccination and from 24 of these cows 175 days after vaccination. Serum neutralizing antibody titers to vsv-New Jersey serotype were determined from serum-dilution, plaque-reduction tests. Serum neutralizing antibody titers also were determined during the same period for 67 nonvaccinated heifers in the herd. Peak group geometric mean serum neutralizing antibody titers of 1:530.46 +/- 1.14 (group geometric mean titer log10, 2.725 +/- 0.055) developed 21 days after the second vaccination, but decreased to a low value of 1:65.36 +/- 1.38 (group geometric mean titer log10, 1.815 +/- 0.142) by 175 days after vaccination. The nonvaccinated group had no detectable antibody titer to vsv-New Jersey serotype throughout the study. All serum specimens from the vaccinates and controls were negative for heterologous reactivity to vsv-Indiana serotype. 相似文献
66.
M R Irwin C A Holmberg H D Knight C A Hjerpe 《American journal of veterinary research》1976,37(2):223-226
In a study on the primary humoral response of calves vaccinated against infectious bovine rhinotracheitis (IBR) and simultaneously given levamisole, mild but consistent suppression of the group's geometric mean serum-neutralization titer to IBR virus occurred between 12 and 59 days later. The quantitative determination of circulating immunoglobulins (Ig) over the same period indicated a slight decrease in the IgG concentrations from an initial geometric mean concentration of 18.28 mg/ml before calves were vaccinated to 15.29 mg/ml after vaccination, and the control calves (vaccinated and given saline solution only) maintained their prevaccination IgG geometric mean concentration of 20.92 mg/ml. Difference was not observed in the circulating IgM values of the 2 groups. Levamisole had no apparent effect on the circulating Ig-bearing lymphocyte values when compared with control calves during the 24 hours of treatment. It was concluded that a single treatment of levamisole may mildly suppress the primary humoral response to IBR vaccination in calves, but it is unlikely that this would affect the animal's capability to recover from, or maintain resistance to, IBR infection. 相似文献
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Exotic Diseases of Animals: a field guide for Australian veterinarians , Geering WA, Forman AJ and Nunn MJ
Student's Guide to Bovine Clinics , 2nd edition, C Pasquini & S Pasquini 相似文献
Student's Guide to Bovine Clinics , 2nd edition, C Pasquini & S Pasquini 相似文献
70.
V E Mendel M R Witt B S Gitchell D N Gribble Q R Rogers H J Segall H D Knight 《American journal of veterinary research》1988,49(4):572-578
Nine adult horses were fed alfalfa hay cubes containing approximately 10% Senecio vulgaris until all horses had consumed approximately the same amount of toxic components of S vulgaris, pyrrolizidine alkaloids (PA). The amount of PA consumed was determined by the amount that induced clinical signs of PA toxicosis in 3 horses. The 6 other horses were given similar amounts per kilogram of body weight. An initial decrease of feed intake was observed when horses' diets were changed from alfalfa cubes to alfalfa/Senecio cubes, and feed intake was decreased further over 89 to 98 days. From 50 to 159 days, body weight decreased in all horses. Liver disease was induced in all 9 horses after they ate an average of 233 +/- 9.2 mg of PA/kg of body weight. Eight horses died or were euthanatized. Treatment with branched chain amino acids had no effect on mortality, but appeared to reduce neurologic problems. Clinical signs of PA-induced liver disease included ataxia, head pressing, and decreased feed intake. Other clinical signs of toxicosis were observed individual horses, but did not develop in most horses. Megalocytic hepatopathy developed. Liver abnormalities proceeded as PA was consumed and were severe in 8 of 9 horses before clinical signs of toxicosis appeared. Sulfobromophthalein sodium clearance did not decrease until PA-induced liver disease was advanced. Bile acid (BA) concentrations increased to greater than or equal to 50 mumol/L, in the 8 horses that died. One horse had hepatopathy and increased BA concentration, but survived. In this horse, BA concentration peaked at 33 mumol/L and then decreased.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献