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1.
Dehorning adult cattle is a surgical procedure causing distress of varying intensities that can be reflected in behavioural changes and alterations in plasma cortisol levels. Stress responses during the dehorning process were evaluated in 18 Red Pied cows. The cows were divided into 3 groups of six and kept in tie-stall housing. Those in the first group were dehorned under general anaesthesia (GA) induced by intravenous administration of xylazine and ketamine. The second group was dehorned under sedation and local anaesthesia (SLA) induced by intramuscular administration of xylazine and local anaesthesia with lidocaine. The third group was dehorned under local anaesthesia (LA) with lidocaine. Dehorning was performed with a foetotomy wire. Blood samples were taken 0.5 h before dehorning to determine cortisol levels, and, by means of a central venous catheter inserted into the jugular vein, during surgery at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7 and 8 h post-surgery. Concurrently, occurrence of stress behaviours was assessed. Cortisol levels were measured by enzyme immunoassay (EIA). The lowest mean peak levels of plasma cortisol (82.53 +/- 6.04 nmol l(-1)), the most rapid return of plasma cortisol levels to baseline values (1.92 +/- 1.11 h), and the lowest occurrence of stress behaviours (2.38 +/- 5.83%) were noted in the SLA group. The highest mean peak levels plasma cortisol (113.86 +/- 25.65 nmol l(-1)), the slowest return of plasma cortisol levels to baseline values (3.83 +/- 2.18 h) and the most frequent occurrence of stress behaviours (65.48 +/- 28.72%) were observed in the LA group. There were significant differences between the SLA and LA groups in peak plasma cortisol levels (p = 0.011) and in occurrence of stress behaviours (p = 0.003). Sedation induced by intramuscular administration of xylazine in conjunction with local anaesthesia with lidocaine is considered the most suitable method of anaesthesia when dehorning adult cattle. Local anaesthesia with lidocaine alone was least suitable.  相似文献   
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A desexed female ferret was presented with bilateral alopecic changes. Clinical examination revealed generalized alopecia and abdominal distension. A polycystic mass was found behind the right kidney, and the whole abdomen was filled with a large turgid mass. Radiography and ultrasonography confirmed the presumptive diagnosis of a hydrometra. Hematology and serum biochemistry showed regenerative anemia with light azotemia. Laparotomy showed the presence of a neoplastic mass at the location of the right ovary, a massive enlargement of the uterus filled with a clear fluid, and a subcapsular cyst on the left kidney. After surgery, histopathologic examination of the tissues diagnosed a leiomyoma of the right ovary with hyperplasia of the uterine wall.  相似文献   
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Zusammenfassung Es wird gezeigt, da? es m?glich ist, durch die Anwendung subletaler Konzentrationen des Insektizids DTHP, d. h. durch eine allgemeine Schw?chung des Organismus erwachsener Rüsselk?fer (Hylobius abietis L.), eine geeignete Disposition dieses Sch?dlings zur Infektion durch den parasitischen PilzBeauveria bassiana (Bals-Criv.) Vuill. herbeizuführen. Die K?fer, die in Fangrinden oder Fallen an Kiefern? stchen — welche in ein kombiniertes Pr?parat einer 0,05% DTHP-Suspension (Organophosphorverbindung vom Dipterex-Typ, technischer Block 0,0-Dimethyl-2,2,2-trichlor-1-hydroxy?thyl-phosphonat) mit 0,1% Sporen vonBeauveria bassiana getaucht worden waren — konzentriert wurden, nahmen keine Nahrung mehr auf und starben allm?hlich ab. Wie die histologischen Untersuchungen gezeigt haben, wurden Erkrankung und Tod der K?fer durch den genannten parasitischen Pilz herbeigeführt. Obwohl nur zwei Vergleichsfl?chen zur Verfügung standen, ist aus dem obengesagten klar, da? bei der Anwendung des kombinierten Pr?parates mit einer gewissen selektiven Wirkung gerechnet werden kann: W?hrend an der nur mit 1% DTHP behandelten Versuchsfl?che ungef?hr 2,5% nützlicher Insekten unter den get?teten K?fern festgestellt wurden (vor allem Laufk?fer der GattungPterostichus), betrug der Prozentsatz der get?teten nützlichen Insekten bei der Anwendung des kombinierten Pr?parates (DTHPBeauveria bassiana-Sporen) nur 0,25%. Die angeführten Versuche bewiesen die Anwendbarkeit der Kombination von Insektiziden — in subletalen Dosen oder Konzentrationen — mit Sporen parasitischer Pilze.  相似文献   
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This article describes the two separate programs of veterinary education offered at the University of Veterinary and Pharmaceutical Sciences in Brno, Czech Republic, which are directed to clinical veterinary medicine and to veterinary food safety, hygiene, and ecology, respectively. Both programs provide a level of training such that all graduates are competent for veterinary practice in any area of veterinary medicine; however, each offers an extended and deepened emphasis of training in clinical medicine, on the one hand, and food safety, on the other. A key feature is that the cohort of students for each program enters having pre-selected a career in one of these two areas. One of the important end results of this structure is that it fulfills the growing and important mission of providing a critical number of veterinarians in food safety and all of its allied fields.  相似文献   
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Total phenolic content, reducing power, antioxidant and free radical scavenging activities of ethanol extracts of five mosses were determined in vitro. No correlation between the total phenolic content and antioxidant or scavenging activities was found.  相似文献   
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The influence of differing soil management practices on changes seen in soil organic carbon (SOC) content of loamy Haplic Luvisol was evaluated. The field experiment included two types of soil tillage: 1. conventional tillage (CT) and 2. reduced tillage (RT) and two treatments of fertilization: 1. crop residues with nitrogen, phosphorus, and potassium (NPK) fertilizers (PR+NPK) and 2. NPK fertilizers (NPK). The results of SOC fluctuated from 9.8 to 14.5 g kg?1 and the tillage systems employed and fertilization status did not have a statistically significant influence on SOC. The SOC content was higher in RT (12.4 ± 0.86 g kg?1) than in CT (12.2 ± 0.90 g kg?1). On average, there was a smaller higher value of SOC in PR+NPK (12.4 ± 1.02 g kg?1) than in NPK (12.3 ± 0.88 g kg?1). During a period of 18 years, reduced tillage and application of NPK fertilizers together with crop residues build up a SOC at an average speed of 7 and 16 mg kg?1 year?1, respectively, however conventional tillage and NPK fertilizer applications caused a SOC decline at an average speed of 104 and 40 mg kg?1 year?1, respectively.  相似文献   
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Dendrobaena mrazeki is an endemic earthworm species inhabiting dry habitats such as pine and thermophilous oak forests in Central Europe. Metabolically, D. mrazeki showed some features typical for endogeic species and some of epigeic ones. In comparison with the related Dendrobaena octaedra, D. mrazeki was a larger earthworm with fresh body mass of adult and subadult individuals of W = 0.59 ± 0.05 g. Its body mass-specific oxygen consumption (M/W = 48 ± 5 μl O2 g?1 h?1, at 15 °C) was the lowest of all earthworms studied (Aporrectodea caliginosa, Aporrectodea rosea, D. octaedra, Lumbricus castaneus, Lumbricus rubellus and Octolasion lacteum), being strongly dependent on W (b from the equation M/W = aWb about ?0.8). D. mrazeki had low relative water content (77.4% of fresh body mass) and small relative amount of dry weight of the intestinal content (20.1% of dry body mass), which is similar to the epigeic D. octaedra. The respiration rate of D. mrazeki remained the lowest even after recalculating M/W to respiration rate per dry mass or per dry mass without the intestine content to correct for the differences among species in body water content and gut content.  相似文献   
10.
The lnbA gene of Lactococcus lactis ssp. lactis IL1403 encodes a polypeptide with similarity to lacto-N-biosidases and N-acetyl-β-D-hexosaminidases. The gene was cloned into the expression vector pET-21d and overexpressed in Escherichia coli BL21* (DE3). The recombinant purified enzyme (LnbA) was a monomer with a molecular weight of approximately 37 kDa. Studies with chromogenic substrates including p-nitrophenyl N-acetyl-β-D-glucosamine (pNP-GlcNAc) and p-nitrophenyl N-acetyl-β-D-galactosamine (pNP-GalNAc) showed that the enzyme had both N-acetyl-β-D-glucosaminidase and N-acetyl-β-D-galactosaminidase activity, thus indicating that the enzyme is an N-acetyl-β-D-hexosaminidase. K(m) and k(cat) for pNP-GlcNAc were 2.56 mM and 26.7 s(-1), respectively, whereas kinetic parameters for pNP-GalNAc could not be determined due to the K(m) being very high (>10 mM). The optimal temperature and pH of the enzyme were 37 °C and 5.5, respectively, for both substrates. The half-life of activity at 37 °C and pH 6.0 was 53 h, but activity was completely abolished after 30 min at 50 °C, meaning that the enzyme has relatively low temperature stability. The enzyme was stable in the pH 5.5-8 range and was unstable at pH below 5.5. Studies with natural substrates showed hydrolytic activity on chito-oligosaccharides but not on colloidal chitin or chitosan. Transglycosylation products were not detected. In all, the data suggest that LnbA's role may be to degrade chito-oligosaccharides that are produced by the previously described chitinolytic system of L. lactis.  相似文献   
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