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141.
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143.
Canine toxocariasis and the associated environmental contamination of urban areas in eastern Nigeria 总被引:1,自引:0,他引:1
The prevalence of canine toxocariasis in pet dogs in two urban towns in eastern Nigeria and the associated environmental contamination were studied through examination of 262 faecal and 400 soil samples. Infection rates in dogs varied from 6.67% to 42.35%, the prevalence rate being inversely related to the age of dogs. Sex and breed of dogs had no significant influence (P greater than 0.05) on the prevalence of infection. There was no evidence of widespread contamination of public places, as Toxocara ova were recovered only from some private premises, namely, those of a dog owner and the kennel of a veterinary hospital. 相似文献
144.
T Mattila J Syv?j?rvi N E Jensen M Sandholm 《American journal of veterinary research》1986,47(1):139-142
Interrelationships between N-acetyl-beta-D-glucosaminidase (indicating cellular damage) and antitrypsin (indicating increased permeability between the blood and milk compartments) were evaluated in 1,411 quarter-milk samples collected during routine herd surveys. N-Acetyl-beta-D-glucosaminidase was antitrypsin, whereas, in more severe mastitis, antitrypsin had a more constant deflection. The sensitivity of both determinants was associated with the virulence of bacteria. Production of bacterial hemolytic toxins was associated with a significant increase in both determinants. Penicillinase production by staphylococci was associated with selective increases of antitrypsin. 相似文献
145.
A Y-maze avoid-avoid choice test was used to elucidate pregnant ewes' relative preference for electro-immobilization as opposed to restraint by a squeeze-tilt table. Choices in successive trials evaluating three commercial electro-immobilizers were: electro-immobilizer-13, 13 and 8% for respective models; squeeze-tilt table-79, 57 and 71%; and no choice-8, 30 and 21%. In all trials combined, 56% of the ewes never chose the electro-immobilizer after once experiencing it, while 94% did choose the squeeze-tilt table one or more times after being restrained by it. Most ewes became more willing to enter the table as experience with it increased, but those that had been both electro-immobilized and table-restrained became more hesitant to pass the test facility's entrance gate as these experiences increased. Ewes accepted a feed reward only reluctantly if at all after being electro-immobilized, but readily after table restraint. Electro-immobilization was clearly more aversive to the ewes than was restraint by a squeeze/tilt table. When restraint by either electro-immobilization or squeeze/tilt table is necessary, use of the table would be indicated in terms of its being less aversive. 相似文献
146.
X-ray diffraction crystallography was used to determine the crystalline composition of 18 equine urinary calculi, including stones originating in the kidney, bladder and urethra. Calcium carbonate in the form of calcite was found to be the major component in all calculi examined. Other components commonly found included weddellite and substituted vaterite. Urine deposits from a number of normal horses were also examined. The significance of these findings, as well as those from a number of previous reports, are discussed in relation to the possible aetiology of urolithiasis in the horse. 相似文献
147.
Brain stem and cerebrocortical potentials were evoked by electrical stimulation of the infraorbital nerve of dogs and recorded through needle electrodes placed adjacent to the contralateral parietal bone. Five individual, short latency peaks were recorded in each averaged trigeminal nerve-evoked potential and were identified as I, II (A and B), III (A and B), PI (A, B, and C), and NI. Mean peak latencies +/- 1 SD were as follows: I = 0.9 +/- 0.1 ms, IIA = 1.7 +/- 0.1 ms, IIB = 2.5 +/- 0.1 ms, IIIA = 3.6 +/- 0.15 ms, IIIB = 4.1 +/- 0.2 ms, PIA = 5.2 +/- 0.15 ms, PIB = 6.4 +/- 0.2 ms, PIC = 7.3 +/- 0.3 ms, and NI = 11.0 +/- 0.6 ms. Trigeminal nerve-evoked potentials recorded through needle electrodes were essentially the same as potentials evoked by direct stimulation of the infraorbital nerve and recorded directly from the dura mater overlying the contralateral rostral suprasylvian gyrus. The specificity of the stimulating site was verified by recording before and after the infraorbital nerve was cut proximal to the stimulating site. 相似文献
148.
149.
T G Nagaraja L R Fina B A Lassman E E Bartley H D Anthony D A Sapienza B E Brent 《American journal of veterinary research》1979,40(1):35-39
Phenol-water extraction of Megasphaera elsdenii, a predominant gram-negative coccus in rumens of cattle fed high-grain diets, yielded material that exhibited typical characteristics of endotoxin. The extract was lethal to mice and to chicken embryos, caused biphasic fever in rabbits, leukopenia in mice, and local and generalized Shwartzman reactions; and induced tolerance to the lethal effect of the endotoxin in mice. The material contained carbohydrate, protein, lipid, phosphorus, and 2-keto-3-deoxyoctonate, but no nucleic acid. The beta-hydroxymyristic acid was absent. Results imply that M elsdenii endotoxin has many biological and chemical characteristics common to enterobacterial endotoxin. However, the median lethal doses in mice and in chicken embryos, and minimal dose required to elicit a local Shwartzman reaction, indicate that M elsdenii endotoxin's potency is low, which may explain why the large gram-negative bacterial population in the rumen of cattle is generally innocuous. 相似文献
150.
S T Ferrell B R Weeks B Abbitt R W Radcliffe 《Journal of zoo and wildlife medicine》2000,31(2):215-220
Three juvenile sable antelope (Hippotragus niger) were diagnosed with bilateral aural hyalohyphomycosis based on histopathology. All three animals were suspected to be immunodeficient based on low IgG levels determined using the zinc sulfate turbidity test. The serum and hepatic copper levels of one animal were below the bovine reference range. Clinical signs in the three animals included bilateral ventral deviation of the pinnae with multifocal subcutaneous aural tumefaction and poor body condition. Numerous septate, nonpigmented fungal hyphae were found within the auricular cartilage, dermis, and subcutaneous granulomas. No significant fungal agents were isolated by culture, and no signs of systemic fungal dissemination were identified except for a concurrent fungal rhinitis in one animal. 相似文献