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71.
Sweeney RW Divers TJ Zamos DT Spencer PA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1998,18(4):103-106
Sixty-three blood samples from 10 diarrheic calves were tested for glucose concentration by two methods. Plasma glucose concentration was measured by the conventional glucose-6-phosphate dehydrogenase method in the clinical laboratory, and the results compared to those obtained using a rapid reagent strip test for blood glucose concentration measurement. The rapid reagent strip test result could not be used to make an accurate prediction of the actual plasma glucose concentration as determined by the conventional method, due to the wide variability in actual plasma glucose concentrations corresponding to each rapid test result. 相似文献
72.
Adult body size and fecundity of a number of hemimetabolous aquatic insects depend largely on thermal conditions during the larval period. Small adults and reduced fecundity result when temperatures are either warmed or cooled with respect to more optimal thermal conditions. Temperature apparently affects adult size by altering the larval growth rate and the timing and rate of adult tissue development for each larva. The data suggest a new interpretation for the geographic distribution of aquatic insects. 相似文献
73.
Benedictus A Mitchell RM Linde-Widmann M Sweeney R Fyock T Schukken YH Whitlock RH 《Preventive veterinary medicine》2008,83(3-4):215-227
A Johne's disease control program, including stringent management practices and a test-and-cull program (whole-herd fecal-samples taken twice a year), was implemented on a medium-sized Pennsylvania dairy farm that was suffering losses from clinical Johne's disease. The data that emerged from the control program, combined with birthdates, culling dates, lactation information and pedigrees, yielded an extensive longitudinal dataset. The dataset was processed through SAS 9.1 for statistical analysis; herd-level disease dynamics and dam-to-daughter transmission parameters were calculated. After the implementation of the program in 1984, prevalence dropped dramatically from 60% to less than 20% in 1989. After an apparent prevalence peak (25%) in 1991 due to improved test sensitivity, prevalence maintained a plateau of 10% from 1996 to 2000. After the implementation of the program, 9.5% of the offspring from test-negative dams and 26.8% of the offspring from known-infected dams became infected with Mycobacterium avium subspecies paratuberculosis (Map) (χ2 = 14.7; p = 0.0001). Calves born shortly following the calving of an infected dam and calves growing up with a future high shedder were more likely to be infected compared to calves without this risk profile. It was concluded that, after the implementation of the control program, the most important causes of infections of susceptible calves were their own dams or infected animals which had calved recently. 相似文献
74.
This article examines a heretofore underexplored category of automotive-producing nation known as the semi-periphery. These nations are neither “core” automotive nations whose power derives from hosting headquarters of major automakers, nor are they low-cost members of the automotive “integrated periphery” like Mexico or countries in Central and Eastern Europe or North Africa. Through a case study of one semi-periphery country, Canada, the paper assesses automotive semi-periphery countries' capacity to transition to knowledge-based activities more typically associated with “core” automotive nations. In so doing, it raises implications for other “semi-periphery” automotive-producing nations as well as those currently categorized as “core” or “integrated periphery.” 相似文献
75.
Isao Yano Brian Tsukimura James N. Sweeney James A. Wyban 《Journal of the World Aquaculture Society》1988,19(4):204-209
Induction of ovarian maturation in Penaeus vannamei , by implantation of ganglion prepared from female lobster, Homarus americanus , with developing ovaries was investigated under tank culture conditions. Four of six females with thoracic ganglion implants were maturing while only two of thirteen females of the control groups with abdominal ganglion or no implant matured. Two ripe stage V were found 18 days after implantation of lobster's thoracic ganglion. This indicates that ovarian maturation of P. vannumei in tanks can be induced and accelerated by implantation of thoracic ganglion prepared from maturing females of another species. Ovarian maturation may be induced by a gonad-stimulating hormone, secreted by the thoracic ganglion of maturing females. This gonnd-stimdating hormone is not species specific in activity in the shrimp and lobster. 相似文献
76.
Raymond W Sweeney Robert H Whitlock Susan McAdams Terry Fyock 《Journal of veterinary diagnostic investigation》2006,18(1):2-6
Two thousand nine hundred fifty-two serum samples, collected once or twice annually from 545 cows of known fecal culture status were tested for antibodies to Mycobacterium avium subsp. paratuberculosis using a commercially available enzyme-linked immunosorbent assay (ELISA) test. Overall, 13.5% of the samples from 282 infected cows had positive ELISA results, but when tested multiple times, 38.3% of the cows had at least 1 serum sample with positive results. Among 263 fecal culture-negative cows, 98.1% of the serum samples had negative ELISA results, but when tested multiple times, 7.8% of the cows had at least 1 positive ELISA sample. Fecal culture was positive on a test before the first positive ELISA in 50 cows, ELISA was positive before fecal culture in 12 cows, and in 38 cows, both tests became positive at the same testing time. An additional 174 cows were positive on fecal culture and always negative on ELISA until culled. For cows that had ELISA sample:positive (S/P) ratios below the cutoff point, the change in S/P between sequential tests was evaluated to determine whether a rise in S/P could predict infection status. In this study, change in S/P was not a useful predictor of infection status in seronegative cows. 相似文献
77.
Raymond W Sweeney Robert H Whitlock Susan C McAdams 《Journal of veterinary diagnostic investigation》2006,18(6):587-590
Three methods of harvesting DNA from broth culture tubes for quantitative real-time polymerase chain reaction (qrtPCR) confirmation of Mycobacterium avium subsp. paratuberculosis (MAP) were evaluated. A commercial DNA extraction kit, the boil method (boiling for 5 minutes), or direct addition of broth culture media to the PCR reaction mix were tested. Samples were evaluated at 8 or 11 days of incubation and at the time of instrument-signal culture-positive. In total, when tested at time to instrument signal positive, 10/10 (100%) of samples extracted by the commercial method were positive on qrtPCR, whereas 9/10 (90%) were positive after the boil method, and 6/10 (60%) were positive after the direct method. Increased volumes of egg-yolk emulsion added to the culture tubes prolonged the number of cycles to threshold positive for the samples that were not subjected to commercial extraction or boiling. Samples were not reliably positive when tested at 8 or 11 days of incubation. The boil method appears to represent a reasonable time- and money-saving method to harvest DNA for qrtPCR confirmation of MAP in broth culture at time to instrument signal positive. 相似文献
78.
79.
Prion protein gene polymorphisms in pedigree sheep in Ireland 总被引:4,自引:0,他引:4
O'Doherty E Aherne M Ennis S Weavers E Roche JF Sweeney T 《Research in veterinary science》2001,70(1):51-56
The development of clinical signs of scrapie in sheep has been linked to polymorphisms in the prion protein (PrP) gene. The most important polymorphisms appear to be at codons 136, 154 and 171. The objective of this study was to investigate polymorphisms at these codons in five native (Belclare, Galway, Wicklow Cheviot, Donegal Blackface Mountain and Mayo Blackface Mountain) and five imported (Texel, Bleu du Maine, Rouge de l'Ouest, Vendéen and Charollais) sheep breeds in Ireland. A total of 13 genotypes were found. The percentage of the most resistant genotype AA(136)RR(154)RR(171)varied from 1.8 per cent in the Vendéen breed, 3.1 per cent in Donegal Blackface Mountain, 10.0 per cent in Texel, 11.1 per cent in Wicklow Cheviot, 12.9 per cent in Belclare, 22.0 per cent in Charollais, 25.6 per cent in Mayo Blackface Mountain, 33.3 per cent in Galway, 46.4 per cent in Bleu du Maine to 62.5 per cent in Rouge de l'Ouest. The results indicate that a significant amount of variation exists between the breeds analysed in this study. 相似文献
80.
Sweeney RW 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(4):463-467
The objective of the study was to test the tolerance of a rice-based oral rehydration formula when fed to calves. Six healthy Holstein calves, 1 week of age, were fed the formula instead of milk replacer for 3 days. Pre- and posttreatment results of clinical examination and laboratory parameters were compared. Vital signs, attitude, appetite, clinical hydration status, urine specific gravity, and most routine serum biochemistry test results did not vary and remained within the normal range. Five of the 6 calves developed diarrhea when fed the rice-based formula, which was accompanied by a reduction in fecal pH and presence of reducing sugars in the feces. This effect was reversed when calves were returned to the milk replacer diet at the end of the study. Diarrhea was accompanied by increased water consumption, which allowed the calves to maintain normal hydration status. These results suggest that calves are unable to properly digest the rice-derived carbohydrate, and this type of formula is not recommended for oral rehydration of calves. 相似文献