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41.
The duck growth hormone encoding gene and its promoter region were amplified by polymerase chain reaction (PCR). A total of 5.25 kb were cloned and sequenced. Duck growth hormone (GH) consists of five exons and four introns and is structurally similar to mammalian and chicken GH gene. Although the distal region of duck GH promoter showed no similarity to chicken and turkey promoters, the proximal region of the promoter contained two putative Pit‐1 binding sequences, and showed similarity to chicken and turkey GH promoters. Genetic variation was detected at five positions of the promoter region. The results of this study indicate that the expression of duck GH is likely regulated in a similar manner to that of chicken GH via enhancer‐type cis‐acting elements and the presence of genetic variation in the duck GH gene may be applicable to marker‐assisted selection.  相似文献   
42.
Sixty female dogs with untreated mammary carcinoma, comprising equal numbers of dogs in tumour stages I to IV, were evaluated for haemostatic abnormalities using the following tests: platelet count, prothrombin time, activated partial thromboplastin time, thrombin time, plasma activity of factor V, VIII and X, plasma concentration of fibrinogen, fibrin monomers and fibrinogen degradation products, and plasma antithrombin III activity. Two-thirds of all dogs had one or more haemostatic test abnormality of which the likelihood and frequency was increased in those with stage III and IV neoplasia. Haemostatic abnormalities were more frequently observed in dogs which had mammary tumours with distant metastases, extended tumour necrosis, inflammatory carcinomas, tumours fixed to underlying structures, or tumours in which there was penetration of the tumour capsule by tumour cells. As in humans with mammary carcinoma, these haemostatic abnormalities might be used as prognostic indicators, but their clinical importance remains unknown.  相似文献   
43.
The sampling of living insects should be avoided in highly endangered species when the sampling would further increase the risk of population extinction. Nonlethal sampling (wing clips or leg removals) can be an alternative to obtain DNA of individuals for population genetic studies. However, nonlethal sampling may not be possible for all insect species. We examined whether remnants of traffic-killed specimens of the endangered and protected flighless longhorn beetle Iberodorcadion fuliginator (L., 1758) can be used as a resource for population genetic analyses. Using insect fragments of traffic-killed specimens collected over 15 yr, we determined the most efficient DNA extraction method in relation to the state of the specimens (crushed, fragment, or intact), preservation (dried, airtight, or in ethanol), storage duration, and weight of the sample by assessing the quantity and quality of genomic DNA. A modified cetyltrimethyl ammonium bromide method provided the highest recovery rate of genomic DNA and the largest yield and highest quality of DNA. We further used traffic-killed specimens to evaluate two DNA amplification techniques (quantitative polymerase chain reaction [qPCR] and microsatellites). Both qPCR and microsatellites revealed successful DNA amplification in all degraded specimens or beetle fragments examined. However, relative qPCR concentration and peak height of microsatellites were affected by the state of specimen and storage duration but not by specimen weight. Our investigation demonstrates that degraded remnants of traffic-killed beetle specimens can serve as a source of high-quality genomic DNA, which allows to address conservation genetic issues.  相似文献   
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45.
A juvenile male mixed breed dog was presented for lethargy, exercise intolerance, and aggression when touched on the head. Cyanosis, tachycardia, and tachypnea were observed and persisted during oxygen supplementation. Arterial blood gas analysis by co‐oximetry identified an increased methemoglobin concentration (27%; normal, <2%) with normal arterial oxygen tension. The methemoglobinemia and associated clinical signs resolved after administration of methylene blue (1 mg/kg) IV, and the dog was discharged. The affected dog's whole‐genome sequence contained 2 potentially causal heterozygous CYB5R3 missense mutations suggesting that cytochrome b5 reductase deficiency was responsible for the methemoglobinemia. This hypothesis was confirmed by enzyme analysis that identified cytochrome b5 reductase activity in the affected dog's erythrocytes to only approximately 6% of that in a control sample. Clinical signs recurred 11 days after discharge but normalized and the methemoglobin concentration decreased with methylene blue administration PO (1.5 mg/kg, initially daily and then every other day).  相似文献   
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Alternative poultry production with special reference to free range broilers has increased significantly since the nineties in many regions of the world. Numerous factors influence the productive performance of this type of broilers: genotype (namely the use of naked neck animals), feeding and access to an outdoor area. The aim of this paper is to study the influence of each of these factors on the productive performance of free range broilers under commercial rearing conditions. A total of 3200, day old chicks of both sexes from naked neck and normally feathered genotypes were used in this trial. After a joint initiation phase, animals were divided into four different treatments with the combination of two concentrates (high vs low energy content) and management (access to outside park or not). Experiment lasted a total of 12 weeks. Live weight date was recorded weekly and a samples of animals from the trial were sacrificed at the age of 8, 10 and 12 weeks, when carcass characteristics were determined. Besides sex, the only factor that seems to affect growth characteristics was genotype as naked neck animals had poorer growth rates than normally feathered. No effect was detected on carcass yields and percentages of carcass components for any of the variables. From the data presented in this trial the practises associated with free range production are of relative inconsequence to the technical animal production parameters and can only be justified by a pressing need to differentiate these products from standard poultry products in what concerns both welfare issues and meat characteristics. The results also indicate that genetic material from alternative poultry production in Europe can be a useful option in poultry production development projects in the tropics.  相似文献   
48.
Background: Testing for canine blood types other than dog erythrocyte antigen 1.1 (DEA 1.1) is controversial and complicated by reagent availability and methodology. Objectives: The objectives of this study were to use available gel column technology to develop an extended blood‐typing method using polyclonal reagents for DEA 1.1, 1.2, 3, 4, 7, and Dal and to assess the use of gel columns for cross‐matching. Methods: Dogs (43–75) were typed for DEA 1.1, 1.2, 3, 4, 7, and Dal. Methods included tube agglutination (Tube) using polyclonal reagents, a commercially available DEA 1.1 gel column test kit (Standard‐Gel) using monoclonal reagent, and multiple gel columns (Extended‐Gel) using polyclonal reagents. Blood from 10 recipient and 15 donor dogs was typed as described above and cross‐matched using the gel column technique. Results: Of 43 dogs typed for DEA 1.1, 23, 25, and 20 dogs were positive using Standard‐Gel, Extended‐Gel, and Tube, respectively. Typing for DEA 1.2 was not achievable with Extended‐Gel. For 75 dogs typed for DEA 3, 4, and 7, concordance of Extended‐Gel with Tube was 94.7%, 100%, and 84%, respectively. Dal, determined only by Extended‐Gel, was positive for all dogs. Post‐transfusion major cross‐matches were incompatible in 10 of 14 pairings, but none were associated with demonstrable blood type incompatibilities. Conclusions: Gel column methodology can be adapted for use with polyclonal reagents for detecting DEA 1.1, 3, 4, 7, and Dal. Agglutination reactions are similar between Extended‐Gel and Tube, but are more easily interpreted with Extended‐Gel. When using gel columns for cross‐matching, incompatible blood cross‐matches can be detected following sensitization by transfusion, although in this study incompatibilities associated with any tested DEA or Dal antigens were not found.  相似文献   
49.
Background: While screening programs have reduced the risk of infectious disease transmission by donors in human and veterinary blood banking, bacterial contamination of blood products has emerged as a major complication in human medicine. Objectives: To describe a Pseudomonas fluorescens (Pf)‐contaminated feline packed RBC (pRBC) unit and experimentally investigate Pf‐contaminated canine pRBCs. Methods: Canine pRBCs were inoculated with Pf‐rich pRBCs from the sentinel feline unit and stored at 4°C or 20°C for 72 hours. Aliquots from the pRBCs were serially evaluated by microscopy, culture, and a eubacterial 16S rRNA real‐time PCR assay. Results: One Pf‐contaminated feline unit turned black after 22 days of storage and was removed from the blood bank; a source was not found, and no other contaminated units were identified. Canine pRBCs spiked with 5 or 25 μL of the sentinel unit became culture‐ and/or 16S PCR‐positive at ≥8 hours at 20°C and 48 hours at 4°C and developed a color change at ≥24 hours. Sensitivity studies indicated that without incubation, inoculation of ≥100 μL Pf‐rich pRBCs was necessary for a positive 16S PCR test result. Conclusions: P. fluorescens grows in stored pRBCs slowly at 4°C and rapidly at 20°C. Screening of blood products for color change, estimating bacterial concentration with microscopy, and 16S PCR testing are simple and fast ways to detect bacteria in stored blood. Aseptic collection, temperature‐controlled storage, and regular visual monitoring of stored units is recommended. Discolored units should not be transfused, but examined for bacterial contamination or other blood product quality problems.  相似文献   
50.
Since 1993, Rhizoctonia crown and root rot (Rhizoctonia solani AG 2–2 IIIB) has represented an increasing problem for sugar beet production in Germany. Up to now, the outbreak of the infection and the spread of the disease within a field cannot be predicted and effective countermeasures are not available. Although little is known about the living conditions of R. solani in soils, abiotic soil properties are likely to influence the disease occurrence. Investigations were carried out based on 60 pairwise comparisons, each consisting of a disease‐affected and an adjacent nonaffected patch on farmers' fields in 2002 and 2003. Soil samples from the top soil layer (0–30 cm) were collected before harvest, and eight of the most frequently mentioned soil properties potentially influencing Rhizoctonia crown and root rot infection were examined: bulk density, texture, carbonate carbon, potassium, phosphorus, organic carbon, total nitrogen, and pH. The occurrence of the disease was significantly related to the soil C : N ratio, indicating the influence of soil organic matter on the disease occurrence. Examinations of soil thin sections showed that organic‐matter particles in the soil serve as a substrate for R. solani. All other soil physical and chemical properties examined did not differ between the disease‐affected and nonaffected patches and seem to be of minor importance.  相似文献   
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