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991.
Three rapid agglutination assays for the identification of Staphylococcus aureus Monostaph (Bionor A/S, Skien, Norway), Staphyslide-Test (BioMerieux, Lyon, France) and Staph-Rapid-Test (Roche, Basel, Switzerland), were compared. A total of 104 Gram-positive, catalase positive cocci were tested: Nineteen Staphylococcus reference strains comprising 15 spp. (4 strains were coagulase positive), and 7 Micrococcus reference strains comprising 4 spp.; 22 food isolates comprising 13 S. aureus, 8 coagulase positive Staphylococcus spp., and 1 Micrococcus sp.; 56 animal isolates comprising 11 S. aureus, 9 S. hyicus subsp. hyicus, 2 S. intermedius, 15 coagulase positive and 19 coagulase negative Staphylococcus spp. Totally 54 strains were coagulase positive. Considering agglutination of a coagulase positive strain as a correct identification, Monostaph, Staph-Rapid-Test, and Staphyslide-Test correctly identified 52 (96.3%), 47 (87.0%) and 48 (89.0%) of the coagulase positive staphylococci, respectively. Monostaph, Staph-Rapid-Test and Staphyslide-Test showed 1 (2.0%), 4 (8.0%) and 4 (8.0%) false positive reactions respectively. Monostaph, Staph-Rapid-Test and Staphyslide-Test gave 0 (0.0%), 6 (5.8%) and 7 (6.7%) non-interpretable reactions, respectively. Monostaph may be a good alternative to the tube-coagulase test for rapid and reliable identification of coagulase positive staphylococci from both food and veterinary sources. However, false negative reactions may occur with coagulase positive strains of S. hyicus subsp. hyicus and S. intermedius. 相似文献
992.
O Stigen 《Acta veterinaria Scandinavica》1991,32(2):197-203
The vertebral columns of 327 clinically normal, 12 to 18 months old dachshunds, were x-rayed. This sample represented 16.1% of all dachshunds registered with the Norwegian Kennel Club in the period 1986-1988. Calcified intervertebral discs were identified in 79 (24.2%) of the dogs and the number of calcified discs in each individual varied from 1 to 11 with a mean of 2.3. Calcified discs were estimated to occur in 23.5% of Norwegian dachshunds. The occurrence of calcified discs in standard-sized dachshunds was higher in the wirehaired variety (27.1%) than in the smoothcoated (16.4%) or longhaired (9.1%) varieties. However, within the longhaired variety the occurrence was higher in dwarfs and kaninchens (36.0%) than in standard-sized dachshunds (9.1%). Calcification was identified in all cervical, thoracic and lumbar intervertebral discs other than T1-2, and was found to be most frequent in the caudal thoracic vertebral column. 相似文献
993.
The post-thaw motility and the acrosome integrity of semen from 4 boars frozen with a programmable freezing machine, in mini (0.25 ml) and maxi (5 ml) plastic straws and in 10 x 5 cm Teflon FEP-plastic bags (0.12 mm thick, 5 ml), were compared. The freezing of the semen was monitored by way of thermo-couples placed in the straws and the bags. Three freezing programmes were used, namely A: from +5 degrees C, at a rate of 3 degrees C/min, to -6 degrees C, held for 1 min at -6 degrees C, and followed by a cooling rate of 20 degrees C/min to -100 degrees C; B: a similar curve except that there was no holding time at -6 degrees C and that the cooling rate was 30 degrees C/min, and C: from +5 degrees C to -100 degrees C, with a cooling rate of 35 degrees C/min, followed by storage in liquid N2. Despite the freezing curve assayed, both the mini-straws and the bags depicted much shorter freezing point plateaus as compared to the maxi-straws. Post-thaw sperm motility as well as the amount of normal apical ridges were equally significantly higher when semen was frozen in mini-straws or in bags than in maxi-straws. Significant differences in these post-thawing parameters were obtained between the freezing curves used. The stepwise freezing procedure A appeared as the best alternative for boar semen, considering this in vitro evaluation. 相似文献
994.
W O Nelson 《Journal of the American Veterinary Medical Association》1991,199(6):696-701
995.
Amantadine resistance among hemagglutinin subtype 5 strains of avian influenza virus 总被引:3,自引:0,他引:3
Several avian influenza virus strains of hemagglutinin subtype 5 were assayed for sensitivity to the antiviral drug amantadine. Most strains exhibited little sensitivity to the drug as measured by plaque reduction. The A/Chicken/Scotland/59 (CS59), however, was highly sensitive, making it easily distinguishable from the other H5 strains. Drug sensitivity of the viruses was also assayed in chicken embryos. The in ovo patterns of amantadine sensitivity differed from those detected in cell culture. The CS59 isolate could not be distinguished from all the other strains on the basis of its response to amantadine in ovo. Although amantadine protected chickens inoculated with CS59 from morbidity and mortality, drug-resistant viruses were readily isolated from the infected birds. As found with other amantadine-resistant variants, the structure of the matrix gene was altered in the resistant isolates. These results demonstrate that amantadine resistance is widespread among avian influenza viruses of the H5 subtype, that drug sensitivity in cell culture does not necessarily reflect responses to amantadine in ovo and in vivo, and, as previously found, amantadine-resistant derivatives of H5 strains may be isolated from birds protected by the drug. 相似文献
996.
O Distl 《Berliner und Münchener tier?rztliche Wochenschrift》1991,104(11):375-383
In totally 3740 cows of the breed German Brown Swiss distributed over 115 herds risk factors for the occurrence of diseases were analysed using a threshold model. Disease data were recorded by ten practitioners in southern Bavaria. The most frequent diseases were fertility disorders, followed by metabolic, udder and calving disorders. The influence of the herds could demonstrated clearly for all diseases analysed. The effect of the lactation number contributed significantly to the frequency of milk fever, mastitis, retained placenta, endometritis/metritis and ovary cysts. Heritability estimates vary between h2 = 0.5% and h2 = 4.2% with exception of anestrus/acyclia (h2 = 8.8%). With higher milk yield of cows the disease frequencies increase, especially fertility diseases. However, increasing herd milk yield is associated with decreasing disease frequencies. A depression of A.I.-parameters and an increase of culling rate caused by diseases could be observed. In the case of the occurrence of uterus- and ovary disorders days open are elongated by 58 days in comparison to cows without diseases. Recording of disease data for use in electronic data processing seems necessary, in order to diminish production diseases by breeding and herd control programmes. An important prerequisite in organization of disease data recording is an efficient cooperation between the veterinary practitioner, farmer, inseminator and the official milk recording organisation. 相似文献
997.
Silvio Peixoto Wilson Wasielesky Jr Fernando D'Incao Ronaldo O. Cavalli 《Journal of the World Aquaculture Society》2003,34(1):50-56
The reproduction of wild-caught Farfantepenaeus paulensis in captivity has been successfully achieved since 1983. However, year-round supply of wild broodstock is costly and unpredictable. This study compares the reproductive performance of animals of similar size (females from 32–33 g and males from 19–21 g) but from different sources: estuary-caught juveniles reared indoors for 9 mo and wild-caught adults from shallow coastal waters. Groups of 20 males and 30 unilaterally eyestalk-ablated females were maintained for 60 d in four maturation tanks under controlled environmental conditions. A higher number of eggs per spawning event (78,414 ± 34,491) and total egg production (4,469,600) were observed for the wild females. Nevertheless, captive females produced a higher number of nauplii (1,788,259) due to their higher percentage of fertilized spawns. Therefore, within the size range of this study, the reproductive performance of estuary-caught F. paulensis juveniles over-wintered indoors was found to be equivalent to that of wild-caught females from shallow coastal waters. 相似文献
998.
R O Ramadan A A Gameel A M el Hassan 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1991,44(1):23-26
Squamous cell carcinoma was recorded in 22 Nadji and 3 Maeimi sheep aged 3-6 years, of which 22 were females. Sixteen tumours involved the eyes, 7 occurred in the skin at different body sites, one developed in the ear and another in the rectum. In five cases secondary deposits were seen in the lymph nodes, nasal passages and upper lip. Surgical treatment was successful in the early stages of tumour development, but in advanced cases recurrences were noted. Histologically the tumours were typical for squamous cell carcinoma and most of them were well differentiated. Solar radiation was pointed out as a possible factor in the aetioloy of the tumour. 相似文献
999.
P.I. Rekwot E.O. Oyedipe P.M. Dawuda V.O. Sekoni 《Veterinary journal (London, England : 1997)》1997,153(3):341-347
Serum testosterone concentrations and the spermiograms of prepuberal bulls fed two levels of protein diets were investigated at 7, 10, 14 and 18 months of age. Scrotal circumference, body condition score and total sperm counts of those animals on a high protein diet were significantly (P <0.05) higher than those on a low protein diet. However, sperm motility, total dead sperm and abnormal sperm did not differ between the treatment groups (P <0.05). One bull fed a high protein diet had significantly higher testosterone concentrations (basal and peak) than a bull fed low protein throughout the four sampling periods (P <0.05). Testosterone concentrations, scrotal circumference, volume of semen, sperm concentration and sperm output of bulls on low and high protein diets increased significantly with age (P <0.05). Peak testosterone concentrations ranged from 1.1. ng ml−1 at 7 months to a maximum of 5.3 ng ml−1 at 18 months. The 24 h secretory patterns of testosterone were episodic, pulsatile or temporal in nature. The peaks occurred mostly in the morning hours and ranged from one to five in number. Protein intake in prepubertal bulls could have significant influence on spermiogram and testosterone production. 相似文献
1000.