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151.
The Elo is a recently established dog breed in which the eye anomaly distichiasis has been frequently observed. Out of a total of 234 Elo dogs ophthalmologically examined over four years, 27.8% of the dogs showed between 1 and 31 distichia. There were twice as many distichia in the upper than in the lower eyelid. Litter size, the number of examinations of Elo dogs per ophthalmologist and the proportion of genes of the Eurasian dog had a significant influence on the prevalence of distichiasis. The error probability for the inbreeding coefficient and the proportion of genes of the Old English Sheepdog were just above the significance limit of p = 0.05. No significance was found for the remaining effects. Heritability for distichiasis was estimated using a linear animal model. After transformation of the linear observed estimate onto the underlying liability scale the heritability estimate was h2 = 0.43.  相似文献   
152.
The breeding of the dog breed Elo was started in 1987. This dog breed was established by using 16 dogs of nine different breeds. All pedigree information of the dogs from 1987 to 2002 was included for the analysis of the proportion of genes of the different founder breeds, of the inbreeding coefficient, and relationship coefficients. Additionally, the number of died puppies per litter were investigated. The Eurasian dog breed contributed about 48% of the genes in the whole Elo dog population. Old English sheepdog and Chow Chow contributed about 23% and 10% of the genes. The other dog breeds were of minor importance. The mean inbreeding and relationship coefficients of the whole Elo dog population were 12.04% and 19.22%, respectively. With the exception of 3.5% of animals, all Elo dogs were related to each other. The mean litter size was 6.39 puppies. The percentage of stillborn puppies per litter averaged at 9.47%. The inbreeding coefficients of the puppies and of their dams, the age of the sire and the dam at the time of birth of the puppies, the litter size, the puppies' year of birth and the proportion of genes of the Chow Chow showed a significant effect on the number of stillborn puppies per litter. The heritability for the frequency of stillborn puppies was estimated using a linear animal model. After transformation of the linear estimates to the underlying liability scale, the heritability amounted to h2 = 0.15.  相似文献   
153.
A timber volume regression model applicable to the state and communal forest area of the federal German state of Rhineland-Palatinate is identified using a combination of airborne laser scanning (ALS)-derived metrics and information from a satellite-based tree species classification map available on the federal state level. As is common in many forest inventory datasets, strong heterogeneity in the ALS data due to different acquisition dates and misclassifications in the tree species classification map had noticeable effects on the regression model’s performance. This article specifically addresses techniques that improve the performance of ordinary least square regression models under such restricting conditions. We introduce a calibration technique to neutralize the effect of misclassifications in the tree species variable that originally caused a residual inflation of 0.05 in adjusted \(R^2\). Incorporating the calibrated tree species information improved the model accuracy by up to 0.07 in adjusted \(R^2\) and suggests the use of such information in forthcoming inventories. We also found that including ALS quality information as categorical variables within the regression model considerably mitigates issues with time lags between the ALS and terrestrial data acquisition and ALS quality variations (increase of 0.09 in adjusted \(R^2\)). The model achieved an adjusted \(R^2\) of 0.48 and a cross-validated root-mean-square error (RMSE\(_{\mathrm{cv}}\)) of 46.7% under incorporation of the tree species and ALS quality information and was thus improved by 0.12 in adjusted \(R^2\) (5% in RMSE\(_{\mathrm{cv}}\)) compared to the simple model only containing ALS height metrics (adjusted \(R^2=0.36\), RMSE\(_{\mathrm{cv}}=51.7\)%).  相似文献   
154.
Host protection from infection relies on the recognition of pathogens by innate pattern-recognition receptors such as Toll-like receptors (TLRs). Here, we show that the orphan receptor TLR13 in mice recognizes a conserved 23S ribosomal RNA (rRNA) sequence that is the binding site of macrolide, lincosamide, and streptogramin group (MLS) antibiotics (including erythromycin) in bacteria. Notably, 23S rRNA from clinical isolates of erythromycin-resistant Staphylococcus aureus and synthetic oligoribonucleotides carrying methylated adenosine or a guanosine mimicking a MLS resistance-causing modification failed to stimulate TLR13. Thus, our results reveal both a natural TLR13 ligand and specific mechanisms of antibiotic resistance as potent bacterial immune evasion strategy, avoiding recognition via TLR13.  相似文献   
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157.
Minimizing the impact of fishing is an explicit goal in international agreements as well as in regional directives and national laws. To assist in practical implementation, three simple rules for fisheries management are proposed in this study: 1) take less than nature by ensuring that mortality caused by fishing is less than the natural rate of mortality; 2) maintain population sizes above half of natural abundance, at levels where populations are still likely to be able to fulfil their ecosystem functions as prey or predator; and 3) let fish grow and reproduce, by adjusting the size at first capture such that the mean length in the catch equals the length where the biomass of an unexploited cohort would be maximum (Lopt). For rule 3), the basic equations describing growth in age‐structured populations are re‐examined and a new optimum length for first capture (Lc_opt) is established. For a given rate of fishing mortality, Lc_opt keeps catch and profit near their theoretical optima while maintaining large population sizes. Application of the three rules would not only minimize the impact of fishing on commercial species, it may also achieve several goals of ecosystem‐based fisheries management, such as rebuilding the biomass of prey and predator species in the system and reducing collateral impact of fishing, because with more fish in the water, shorter duration of gear deployment is needed for a given catch. The study also addresses typical criticisms of these common sense rules for fisheries management.  相似文献   
158.
The Federal Institute for Risk Assessment wants to be a competent scientific adviser for politics, administration and the public in risk evaluation and risk communication regarding consumer products. Fields of research needed for this advice are compared with the research universities have to carry out. Examples were given.  相似文献   
159.
Endoscopic retrograde cholangio-pancreatography is a combination of endoscopy and fluoroscopy used for radiographic imaging of the biliary and pancreatic ducts. In order to assess its feasibility and to describe abnormal findings in dogs, this technique was performed in 30 dogs with nonspecific chronic gastrointestinal disturbances. Using an 11-mm side-view endoscope, retrograde cholangiography was successful in 20/30 dogs (67%) and pancreatography in 21/30 (70%). Success was affected by intraduodenal food, mucus or blood, problems in papillary cannulation, stomach overdistention, body size, and changes in duodenal mucosa. It was impossible to perform the procedure in dogs weighing < 10 kg with the available material. Endoscopic retrograde cholangiography revealed findings that differed from previous reports in healthy beagles in 5/20 dogs. Findings included enlarged common bile duct (n = 2), intraductal filling defects (n = 2), and deviated course of common bile duct (n = 1), and major papilla stenosis (n = 1). In the dog with major papilla stenosis and intraductal filling defects, endoscopic guided sphincterotomy was performed. Endoscopic retrograde pancreatography revealed an abnormal course of the accessory pancreatic duct in 2/21 dogs. In both dogs with proven end-stage pancreatic acinar atrophy, the left duct branch did not run distal the stomach to the left but went parallel to the right duct branch and the duodenum. Repeated clinical and laboratory examinations revealed no signs of complications after endoscopic retrograde cholangio-pancreatography. It was concluded that this imaging technique is promising for the diagnosis of biliary and pancreatic diseases in dogs. It also offers the chance for new treatment options such as endoscopic guided sphincterotomy in dogs.  相似文献   
160.
An experiment was conducted to evaluate the effects of a restriction to home-grown feedstuffs and abstinence from supplementation with synthetic amino acids (AA), as ideal objectives in organic pig production according to the IFOAM standards, on growth performance and carcass characteristics. One hundred individually housed pigs were allocated to four dietary treatments and fed from growing through finishing to compare three organic barley/wheat-based diets with an isocaloric conventional diet supplemented with synthetic AA. Protein sources in the organic treatments were either faba beans, supplemented with potato protein to the same AA level as the control diet, peas and lupines, or faba beans and lupines, both without further supplementation, leading to a lower level of limited AA. Supplementation of organic diets with potato protein resulted in the same performance as supplementing the conventional diet with synthetic AA, although crude protein levels differed markedly. Pigs fed the organic diets without AA supplementation grew more slowly (P < .05) and had a decreased feed intake in the grower period (P < .05) but nearly the same feed efficiency (P > .05) as pigs fed conventional or organic diets with AA supplementation. Carcass characteristics differed in percentage of lean meat and longissimus area, being lower in the treatments without AA supplementation (P < .05). However, the intramuscular fat was higher without AA supplementation (2.9% fat) than with supplementation (1.2% fat) (P < .01). The data show that the exclusion of AA supplementation resulted in a reduction in pig performance but in an increase in intramuscular fat content; the latter is an important aspect of eating quality characteristics.  相似文献   
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