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991.
Sidaway BK McLaughlin RM Elder SH Boyle CR Silverman EB 《American journal of veterinary research》2004,65(9):1216-1222
OBJECTIVE: To objectively evaluate the effect of transecting the tendon of the biceps brachii muscle (BBT), tendon of the infraspinatus muscle (IFS), or medial glenohumeral ligament (MGHL) on shoulder joint stability in canine cadavers. SAMPLE POPULATION: 81 forelimbs from mature dogs. PROCEDURE: Cadaver forelimbs were placed in a testing frame and axially preloaded with 4 kg of weight. Shoulder joint stability was tested in neutral joint position, flexion, and extension before and after transection of the BBT (n = 37), IFS (37), or MGHL (7). Humeral translation relative to the glenoid was induced by applying a 3-kg load in each of 3 directions (cranial, lateral, and medial) and quantitatively measured by use of an electromagnetic motion tracking system. Peak translational data were compared in each joint position before and after transection of the BBT, IFS, or MGHL. RESULTS: When tested in neutral position, the cranial, lateral, and medial translation of the humerus was significantly increased after BBT transection. In the flexed position, translation of the humerus in the cranial and lateral directions was significantly increased after BBT transection. In the extended position, the medial translation of the humerus was significantly increased after BBT transection. Complete medial luxation of all humeral heads occurred following transection of the MGHL. CONCLUSIONS AND CLINICAL RELEVANCE: The BBT contributes to passive shoulder joint stability in dogs, particularly in the neutral and flexed positions. It also provides medial stability during shoulder joint extension. Complete luxation of the joint occurs when the MGHL is transected. 相似文献
992.
Kupper J Waidyasekera D Schönenberger W Demuth D Althaus RF Naegeli H 《DTW. Deutsche tier?rztliche Wochenschrift》2004,111(11):433-438
Poisonings can cause reduced performance and severe economic loss in farm animals. A swift and targeted action is required from veterinarians. We have established a computer-based decision support system for poisonings in ruminants and pigs. The system offers access to the most recent information available in clinical toxicology of farm animals. Towards this goal, relevant reports from the peer-reviewed literature were evaluated and organised according to the requirements of a structured database. The information provided for each toxic substance includes a summary of its chemical and physical properties, sources, commercial uses or natural occurrences, toxicokinetic data, mechanisms of action, threshold doses, clinical symptoms with brief case reports, sampling and analytical results, post-mortem abnormalities, differential diagnoses, therapeutic guidelines and references to the literature. This decision support system has been programmed with two user-friendly search functions: a search tool that allows the choice of clinical and pathological findings, and another function that serves to find a substance using its chemical name, the class of compounds to wich it belongs, a possible source or one of its main applications. CliniTox can be accessed directly via our webserver (http://www.clinitox.ch). 相似文献
993.
Maintenance of gastric pH above 4.0 aids the prevention of bile acid-mediated ulcerative damage to the pars esophageal tissue in pigs. One means of doing so is the addition of buffering compounds, such as sodium bicarbonate, to the water supply; however, any potential physiological effect of buffer consumption has yet to be determined. Experiment 1 tested the acute effects of buffer addition to the water supply on systemic acid-base and electrolyte balance in swine (BW 40.7 +/- 3.0 kg). Consumption of water calculated to a 200 mOsm solution with sodium bicarbonate for 24 h increased (P < 0.05) blood Na+, HCO3(-), and pCO2, although these effects were all within physiologically tolerable levels. Urine pH and Na+ excretion increased (P < 0.001) following the consumption of NaHCO3, with Na+ concentration almost threefold higher in treated pigs compared with controls. Experiment 2 determined the chronic systemic effects of buffer consumption by measuring blood and urine variables, with pigs consuming NaHCO3-treated water throughout. Water consumption increased (P < 0.001) during buffer consumption, although intake levels remained within normal ranges. Blood pH levels were not affected by long-term consumption of dietary buffer; however, blood HCO3(-) (P < 0.05), Na+, and pCO2 (P < 0.01) increased. Urine pH and urine Na+ concentration increased (P < 0.01) in buffer-treated compared with control animals. Results indicate that sodium bicarbonate can safely be added to the water supply for pigs, with no clinically relevant alterations in acid-base balance because the animals readily compensate for buffer intake. 相似文献
994.
Twenty-four calves were immunised four times with gE-deleted infectious bovine rhinotracheitis marker vaccines before being challenged with small doses of wild-type bovine herpesvirus type 1 (BHV-1). The repeated vaccinations induced strong immunity that prevented detectable virus replication and gE-seroconversion after the challenge infection in most of the calves. The hypervaccinated calves that shed virus after the challenge infection showed no delay in gE-seroconversion compared with unvaccinated control calves. Using a sensitive nested PCR, BHV-1 gE sequences could be detected in the trigeminal ganglia of several of the gE-seronegative, challenge-infected calves, possibly indicating the presence of wild-type BHV-1 DNA. 相似文献
995.
REASONS FOR PERFORMING STUDY: Sacroiliac joint (SIJ) disease is associated with poor hindlimb action, lameness and poor performance in horses. However, little is known about the biomechanics of this low-motion joint. OBJECTIVES: To determine in vitro the capacities of movement of the SIJ in the sagittal plane, and to test the effect of a sacrosciatic and sacrotuberal desmotomy on its stabilisation. METHODS: Six anatomical specimens underwent cycles of flexion-extension of the lumbosacral joint (LSJ) before and after desmotomy. Kinematic triads were linked rigidly to the sacrum, spinous process of vertebra L5 and iliac wing. Angles were measured using a joint coordinate system based on anatomical frames. RESULTS: The LSJ underwent regular movements of flexion and extension (overall mean +/- s.d. range 23.4 +/- 1.6 degrees). The only recorded movement of the SIJ was a nutation during LSJ flexion (overall mean +/- s.d. 0.8 +/- 0.5 degrees). Desmotomy induced an increase of that nutation (overall mean +/- s.d. 1.7 +/- 0.2 degrees). CONCLUSIONS AND POTENTIAL RELEVANCE: Movements of the SIJ were small and coupled only with the flexion of the LSJ. The ligaments surrounding the SIJ have a strong effect on the stabilisation of this joint. Due to the limited amount of movement, its biomechanical study in vivo seems to be difficult. Further in vitro studies would be useful to determine the role of each ligament, to better understand the clinical consequences of the tears frequently observed during necropsy. 相似文献
996.
PK-PD integration and modeling of marbofloxacin in sheep 总被引:1,自引:0,他引:1
The fluoroquinolone antimicrobial drug, marbofloxacin, was administered intravenously (IV) and intramuscularly (IM) to sheep at a dose rate of 2 mg kg−1 in a 2-period cross-over study. Using a tissue cage model of inflammation, the pharmacokinetic properties of marbofloxacin were established for serum, inflamed tissue cage fluid (exudate) and non-inflamed tissue cage fluid (transudate). For serum, after IV dosing, mean values for pharmacokinetic parameters were: clearance 0.48 L kg−1 h−1; elimination half-life 3.96 h and volumes of distribution 2.77 and 1.96 L kg−1, respectively, for Vdarea and Vss. After IM dosing mean values for pharmacokinetic variables were: absorption half-time 0.112 h, time of maximum concentration 0.57 h, terminal half-life (T½el) 3.65 h and bioavailability 106%. For exudate, mean T½el values were 12.38 and 13.25 h, respectively, after IV and IM dosing and for transudate means were 13.39 h (IV) and 12.55 h (IM).The in vitro minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) and ex vivo time-kill curves for marbofloxacin in serum, exudate and transudate were established against a pathogenic strain of Mannheimia haemolytica. Integration of in vivo pharmacokinetic data with MIC determined in vitro provided mean values of area under curve (AUC)/MIC ratio for serum, exudate and transudate of 120.2, 156.0 and 156.6 h after IV dosing and 135.5, 165.3 and 146.2 h after IM dosing, respectively. After IM administration maximum concentration (Cmax)/MIC ratios were 21.1, 6.76 and 5.91, respectively, for serum, exudate and transudate. The ex vivo growth inhibition data after IM administration were fitted to the sigmoid Emax (Hill) equation to provide values for serum of AUC24 h/MIC producing, bactericidal activity (22.51 h) and virtual eradication of bacteria (35.31 h). It is proposed that these findings might be used with MIC50 or MIC90 data to provide a rational approach to the design of dosage schedules which optimise efficacy in respect of bacteriological as well as clinical cures. 相似文献
997.
M.H.C. Aquino A.L.L. Filgueiras K.R.N. Santos M.C.S. Ferreira A. Tibana 《Research in veterinary science》2010,88(2):214-217
To compare the genotypes of Campylobacter jejuni and Campylobacter coli isolates of human and animal origin collected in Rio de Janeiro City, 30 C. jejuni and 35 C. coli isolates from animal sources (n = 45) and human patients with gastroenteritis (n = 20) were genotyped by PCR-based techniques, namely random amplified polymorphic DNA (RAPD-PCR) and enterobacterial repetitive intergenic consensus sequence (ERIC-PCR). RAPD-PCR identified 50 types and ERIC-PCR identified 22 genotypes, among the 65 Campylobacter isolates. Both PCR methods discriminated the C. jejuni and C. coli groups of isolates. Combining the results of both methods, no single genotype was shared between isolates from human and animal sources. Two groups of two C. coli isolates each with identical genotypes were found among poultry and pig isolates. A high level of genetic diversity observed among the Campylobacter isolates suggests lack of overlap between isolates from different sources. 相似文献
998.
Inhibin is a heterodimeric glycoprotein hormone involved in the regulation of FSH release from the anterior pituitary gland and it has been characterized from various animals. Although, multiple molecular forms of inhibin have been reported from different species, however, the molecular nature of inhibin has not been studied in buffaloes. In the present study, attempts were made to identify inhibin in buffalo ovarian follicular fluid. Buffalo ovaries were obtained from the local abattoir and follicular fluid was aspirated from surface follicle (with diameter ?5 mm). A combination of techniques (viz., gel filtration, SDS-PAGE, Western blot etc.) was employed for identification and isolation of inhibin(s). Inhibin bands were detected at 129 and 63 kDa by Western blot analysis in non-reducing conditions. In reduced SDS-PAGE, 63 kDa fraction produced a single band while 129 kDa fraction resolved into four components of 63, 43, 29 and 20 kDa. Out of them only 29, 63 and the native 129 kDa fractions produced bands on Western blot analysis. In total five fractions (63, 54, 39, 29, 25 kDa) were obtained by trypsin digestion of 129 kDa form. However, only 63 and 29 kDa fractions showed immunoreactivity. In this study, for the first time, we have identified two major forms of inhibin (129 and 63 kDa) with little proteolytic cleavage/processing of the large precursor in the buffalo follicular fluid. 相似文献
999.
Warman SM Helps CR Barker EN Day S Sturgess K Day MJ Tasker S 《The Journal of small animal practice》2010,51(10):534-539
Objective : The aim of this study was to investigate whether the two canine haemoplasma species, Mycoplasma haemocanis and “Candidatus Mycoplasma haematoparvum,” are commonly associated with immune-mediated haemolytic anaemia (IMHA) in UK dogs. Methods : Three groups of dogs were recruited to the study: anaemic dogs with primary IMHA (n=37); anaemic dogs not meeting the inclusion criteria for primary IMHA (n=77) and non-anaemic dogs (n=113). DNA was extracted from 100 μl of blood and subjected to real-time quantitative polymerase chain reaction (qPCR) assays for both species of Mycoplasma. Each assay incorporated co-amplification of canine glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an endogenous internal control. Results : Canine GAPDH was successfully amplified by qPCR from all 227 canine blood samples but none contained M. haemocanis or “Candidatus M. haematoparvum” DNA. Clinical Significance : Haemoplasma infection is uncommon in dogs in the UK and no evidence was found that these organisms act as triggers for IMHA. 相似文献
1000.
H Iwata H Tanaka T Kanke Y Sakaguchi K Shibano T Kuwayama Y Monji 《Reproduction in domestic animals》2010,45(5):888-895
Follicle growth, oocyte quality or oocyte growing environment (follicular fluid) were evaluated in cows with severe liver damage (haemorrhage, telangiectasis, cholangitis and abscess) that were visually diagnosed at the slaughterhouse. Holstein cows aged 40–90 months with either a healthy liver (HL cow) or damaged liver (DL cow) were selected as donors. Follicle development kinetics was evaluated by counting the follicles at various developmental stages. In addition, the biochemical characteristics of the follicular fluids, developmental competence of preantral follicles cultured for 16 days in vitro and the ability of oocytes to develop to the blastocyst stage 8 days after fertilization were examined. DL cows had fewer secondary follicles than HL cows, and the correlation between the number of secondary follicles and the number of primary follicles differed among DL and HL cows. The follicular fluid of DL cows contained significantly lower levels of albumin and a higher total protein content than that of HL cows. Oocyte nuclear maturation assessed at 5, 16 and 21 h after beginning of culture was slower in DL cows than in HL cows, although the final maturation rates did not differ. The rate of polyspermic fertilization was significantly higher and the proportion of cleavage at 48 h after insemination and blastulation lower in DL cows compared with HL cows. When preantral follicles were cultured in vitro, the rate of follicles with normal morphology was lower in DL cows than in HL cows. These findings suggest that the kinetics of folliculogenesis differ among DL and HL cows and the developmental ability of preantral follicles and oocytes is lower in DL cows than in HL cows. 相似文献