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191.
102 fattened pigs with known genetic origin were tested on a conveyor-belt 1--4 days before slaughtering. 64 animals run in the first passage in each case 154 m in a 4 minutes (0.64 m/s), compared to it the 38 animals of the second passage run in each case 770 m in 20 minutes. Measurements of heart frequency and breathing and body temperature were taken before and at intervals until 30 minutes after movement. After slaughtering the values of pH, colour and drip loss of the M. longissimus dorsi were measured. It turned out a difference in the meat quality with a high part of PSE-meat in the first passage (36%), caused by season. The criterion "recovery time of heart action after load" was able to value the stress susceptibility in dependence on meat quality p.m. Animals with a longer recovery time exhibited a lower pH45 value, a lighter colour and a higher drip loss of meat. But only after a certain stress intensity (2. passage) the assertion was given. 相似文献
192.
Elschner M Schrader C Hotzel H Prudlo J Sachse K Eichhorn W Herbst W Otto P 《Veterinary microbiology》2005,105(2):123-129
A total of 26 rotavirus positive faecal samples of diarrhoeal foals, and 8 equine rotavirus isolates were examined. Viral RNA patterns were generated, G typing was performed by PCR, and a P[12]-specific DNA probe was developed for P typing. Furthermore, five equine rotavirus isolates were sequenced in the genomic regions coding for VP7 and part of VP4. Rotaviruses of genotype G3 P[12] were found in 22 faecal samples and G14 P[12] type could be found in 4 faecal samples. These findings confirm that in Germany G3 P[12] is the predominating type of equine rotaviruses. 相似文献
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196.
We have made a biological model based on a Bayesian network for risk factors for infection with Mycoplasma hyopneumoniae (Mycoplasma) in slaughter pigs; prevalence of infection is based on veterinary examinations. The model is a probabilistic/stochastic determination based on the inherent biological uncertainty of the severity of infection with Mycoplasma and the derived stochastic effects on productivity for the herd. The conditional probabilities in the Bayesian network are based on published studies and expert opinions. We used the model to calculate how the risk factors and our evidence about the herd influenced our view on the severity of Mycoplasma, and how our view changed when we had more veterinary evidence. We also show how one can use the model to deal with conflicting examinations. 相似文献
197.
Otto CM Downend AB Serpell JA Ziemer LS Saunders HM 《Journal of the American Veterinary Medical Association》2004,225(6):861-867
OBJECTIVE: To evaluate early medical and behavioral effects of deployment to the World Trade Center, Fresh Kills Landfill, or the Pentagon on responding search-and-rescue (SAR) dogs. DESIGN: Prospective double cohort study. ANIMALS: The first cohort included SAR dogs responding to the September 11, 2001, terrorist attacks (deployed), and the second cohort included SAR dogs trained in a similar manner but not deployed (controls). Enrollment occurred from October 2001 to June 2002. PROCEDURE: Dogs were examined by their local veterinarians; thoracic radiographs and blood samples were shipped to the University of Pennsylvania for analysis. Handlers completed medical and training histories and a canine behavioral survey. RESULTS: Deployed dogs were older and had more search experience than control dogs. Serum concentrations of globulin and bilirubin and activity of alkaline phosphatase were significantly higher in deployed dogs, independent of age and training. Despite significant differences in several blood parameters, values for both groups were within reference ranges. No pulmonary abnormalities were detected on radiographs, and no significant differences in behavior or medical history were detected between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Within the first year following the September 11 attacks, there was no evidence that responding dogs developed adverse effects related to their work. Mild but significantly higher serum concentrations of globulin and bilirubin and activity of alkaline phosphatase in deployed dogs suggested higher antigen or toxin exposure. These dogs will be monitored for delayed effects for at least 3 years. 相似文献
198.
Since individual tree leaf area is an important measure for productivity as well as for site occupancy, it is of high interest in many studies about forest growth. The exact determination of leaf area is nearly impossible. Thus, a common way to get information about leaf area is to use substitutes. These substitutes are often variables which are collected in a destructive way which is not feasible for long term studies. Therefore, this study aimed at testing the applicability of using substitutes for leaf area which could be collected in a non-destructive way, namely crown surface area and crown projection area. In 8 stands of Norway spruce (Picea abies L. Karst.), divided into three age classes and two thinning treatments, a total of 156 trees were felled in order to test the relationship between leaf area and crown surface area and crown projection area, respectively. Individual tree leaf area of the felled sample trees was estimated by 3P-branch sampling with an accuracy of ±10%. Crown projection area and crown surface area were compared with other, more commonly used, but destructive predictors of leaf area, namely sapwood area at different heights on the bole. Our investigations confirmed findings of several studies that sapwood area is the most precise measure for leaf area because of the high correlation between sapwood area and the leaf area. But behind sapwood area at crown base and sapwood area at three tenth of the tree height the predictive ability of crown surface area was ranked third and even better than that of sapwood area at breast height (R2 = 0.656 compared with 0.600). Within the stands leaf area is proportional to crown surface area. Using the pooled data of all stands a mixed model approach showed that additionally to crown surface area dominant height and diameter at breast height (dbh) improved the leaf area estimates. Thus, taking dominant height and dbh into account, crown surface area can be recommended for estimating the leaf area of individual trees. The resulting model was in line with many other findings on the leaf area and leaf mass relationships with crown size. From the additional influence of dominant height and dbh in the leaf area model we conclude that the used crown model could be improved by estimating the position of the maximum crown width and the crown width at the base of the crown depending on these two variables. 相似文献
199.
Traute-Heidi Anderson Otto Heinemeyer Hans-Joachim Weigel 《Soil biology & biochemistry》2011,43(5):895-904
In soil ecology, microbial parameters have been identified as sensitive indicators of changes in the soil environment. The Braunschweig FACE project provided the opportunity to study the effects of elevated CO2 (550 μmol mol−1) as compared to ambient CO2 (370 μmol mol−1) on total microbial biomass (Cmic), Cmic-to-Corg ratio and the fungal-to-bacterial respiratory ratio together with total Corg, Nt, C:N ratio and pH over a six-year period. Field management followed a typical crop rotation system of this region with either a crop-related full nitrogen supply (N100) or 50% reduced N supply (N50). The soil microbial parameters responded to the elevated CO2 treatment in varying intensities and time spans. The fungal-to-bacterial respiratory ratio was the most sensitive parameter in responding to an elevated CO2 treatment with highly significant differences to ambient CO2-treated control plots in the third year of CO2 fumigation. After six years bacterial respiratory activity had increased in ascending order to 34% in FACE-treated plots (N50 and N100) as compared to control plots. Soil microbial biomass (Cmic) responded more slowly to the FACE treatment with highly significant increases of >12% after the fourth year of CO2 fumigation. The Cmic-to-Corg ratio responded very late in the last two years of the CO2 treatment with a significant increase of >7.0% only in the N100 variant. Total Corg and Nt were slightly but significantly increased under FACE around 10.0% with ascending tendency over time starting with the second year of CO2 treatment. No significant FACE effects could be recorded for the C:N ratio or pH.These results suggest that under FACE treatment changes in the soil microbial community will occur. In our study the fungal-to-bacterial respiratory ratio was superior to total Cmic as microbial bioindicators in reflecting changes in the soil organic matter composition. 相似文献
200.
Abstract The germination of alang-alang rhizome buds was found to be affected by the colour of the buds, the length of the rhizome sections, and the orientation of the sections in the cultural medium. The position of the buds on the sections did not affect the germination of the buds, nor did the differences in diameter of the rhizomes. Subsequent growth of the buds was positively affected by increasing the lengths of the sections. 相似文献