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901.
902.
Radiodiagnostic methods have not been used previously for studying the anatomy and diseases of the swimbladder of freshwater fish species. In this study, the radiographic anatomy of the swimbladder and species-related differences in swimbladder structure were studied on plain radiographs taken of 12 Hungarian fish species of major economic importance. Changes observed by radiography were also studied by conventional parasitological methods. The radiodiagnostic method reported here appears to be a useful complement to diagnostic examinations that have been based merely on dissection so far. It enables evaluation of the pathological lesions in live condition, without causing damage to the fish. 相似文献
903.
Occurrence of Grapevine Pinot gris virus in Friuli Venezia Giulia (Italy): field monitoring and virus quantification by real‐time RT‐PCR 下载免费PDF全文
G. L. Bianchi F. De Amicis L. De Sabbata N. Di Bernardo G. Governatori F. Nonino G. Prete T. Marrazzo S. Versolatto C. Frausin 《EPPO Bulletin》2015,45(1):22-32
Since 2003 the presence of a new syndrome characterized by symptoms of stunting, chlorotic mottling, leaf deformation, reduced yields and quality has been reported in some white berry varieties of Vitis vinifera in Trentino‐Alto Adige and Friuli Venezia Giulia vineyards. The identification of a new virus, provisionally called Grapevine Pinot gris virus (GPGV), in a cv. Pinot gris vine suggested an association between this new syndrome and the virus presence (Giampetruzzi et al., 2012), however the contemporary presence of GPGV in both symptomatic and asymptomatic plants has still to be explained. In this work, a large‐scale monitoring over a 3‐year period (2012–14) of Friuli Venezia Giulia vineyards and nurseries has shown a widespread presence of GPGV in symptomatic plants and also in asymptomatic vines, even if at a slightly lower percentage. Quantitative analyses of the virus titer revealed a great variability in the viral content of both symptomatic and asymptomatic plants but the mean GPGV quantity in symptomatic vines was significantly higher than in asymptomatic plants. 相似文献
904.
Four monoclonal antibodies (mAbs) (9.49, 24.27, 46.71 and 179.57) were produced against Fasciola hepatica excretory-secretory products. Isotype analysis revelead the antibodies to be IgM, IgG3, IgG1, and IgM. In immunoblot assays, the mAbs recognized different antigenic polypeptides migrating between 29 and 180 kDa. Specificity of the mAbs was evaluated by ELISA against antigens of Fascioloides magna, Anoplocephala magna, Stichorchis subtriquetrus, Haemonchus contortus, sheep liver extract (SLE), bovine liver extract (BLE), bovine serum albumin (BSA), bovine viral diarrhea virus (BVDV), and Madin-Darby bovine kidney (MDBK) cells. Monoclonals 9.49 and 24.27 were specific, and reacted only with Fasciola hepatica antigens. However, mAb 46.71 cross-reacted with antigens of Fascioloides magna, A. magna, Stichorchis subtriquetrus, and H. contortus but not with SLE, BLE, BSA, BVDV or MDBK cells. Monoclonal antibody 179.57 cross-reacted with Fascioloides magna, A. magna, S. subtriquetrus, H. contortus, SLE, and BLE, but not with BSA, BVDV, or MDBK cells. 相似文献
905.
Combined Campylobacter jejuni and Campylobacter coli Rapid Testing and Molecular Epidemiology in Conventional Broiler Flocks 下载免费PDF全文
G. Schallegger S. Muri‐Klinger K. Brugger C. Lindhardt L. John M. Glatzl M. Wagner B. Stessl 《Zoonoses and public health》2016,63(8):588-599
Campylobacter spp. are important causes of bacterial zoonosis, most often transmitted by contaminated poultry meat. From an epidemiological and risk assessment perspective, further knowledge should be obtained on Campylobacter prevalence and genotype distribution in primary production. Consequently, 15 Austrian broiler flocks were surveyed in summer for their thermophilic Campylobacter spp. contamination status. Chicken droppings, dust and drinking water samples were collected from each flock at three separate sampling periods. Isolates were confirmed by PCR and subtyped. We also compared three alternative methods (culture‐based enrichment in Bolton broth, culture‐independent real‐time PCR and a lateral‐flow test) for their applicability in chicken droppings. Twelve flocks were found to be positive for thermophilic Campylobacter spp. during the entire sampling period. Seven flocks (46.6%) were contaminated with both, C. jejuni and C. coli, five flocks harboured solely one species. We observed to a majority flock‐specific C. jejuni and C. coli genotypes, which dominated the respective flock. Flocks within a distance <2 km shared the same C. jejuni genotypes indicating a cross‐contamination event via the environment or personnel vectors. Multilocus sequence typing (MLST) of C. jejuni revealed that the majority of isolates were assigned to globally distributed clonal complexes or had a strong link to the human interface (CC ST‐446 and ST4373). The combination of techniques poses an advantage over risk assessment studies based on cultures alone, as, in the case of Campylobacter, occurrence of a high variety of genotypes might be present among a broiler flock. We suggest applying the lateral‐flow test under field conditions to identify ‘high‐shedding’ broiler flocks at the farm level. Consequently, poultry farmers and veterinarians could improve hygiene measurements and direct sanitation activities, especially during the thinning period. Ultimately, real‐time PCR could be applied to quantify Campylobacter spp. directly from chicken droppings and avoid non‐interpretable results achieved by culture‐dependent methods. 相似文献
906.
Pharmacokinetics of xylazine after 2-, 4-, and 6-hr durations of continuous rate infusions in horses
Klaus Hopster Lawrence R. Soma Xiaoqing Li Charlotte Hopster-Iversen Raymond C. Boston Bernd Driessen 《Journal of veterinary pharmacology and therapeutics》2020,43(6):557-564
Intravenous (i.v.) bolus administration of xylazine (XYL) (0.5 mg/kg) immediately followed by a continuous rate infusion (CRI) of 1 mg kg−1 hr−1 for 2, 4, and 6 hr produced immediate sedation, which lasted throughout the duration of the CRI. Heart rate decreased and blood pressure increased significantly (p > .05) in all horses during the first 15 min of infusion, both returned to and then remained at baseline during the duration of the infusion. Compartmental models were used to investigate the pharmacokinetics of XYL administration. Plasma concentration–time curves following bolus and CRI were best described by a one-compartment model. No differences were found between pharmacokinetic estimates of the CRIs for the fractional elimination rate constant (Ke), half-life (t1/2e), volume of distribution (Vd), and clearance (Cl). Median and range were 0.42 (0.15–0.97)/hr, 1.68 (0.87–4.52) hr, 5.85 (2.10–19.34) L/kg, and 28.7 (19.6–39.5) ml min−1 kg−1, respectively. Significant differences were seen for area under the curve ( ) (p < .0002) and maximum concentration (Cmax) (p < .04). This indicates that with increasing duration of infusion, XYL may not accumulate in a clinically relevant way and hence no adjustments are required in a longer XYL CRI to maintain a constant level of sedation and a rapid recovery. 相似文献
907.
908.
Hayden E Williams Brittany Carrender Cierra D Roubicek Ryan Maurer Joel M DeRouchey Jason C Woodworth Steve S Dritz Michael D Tokach Kyle F Coble Robert D Goodband Jordan T Gebhardt 《Journal of animal science》2021,99(3)
Two experiments were conducted to evaluate the effects of Fe injection timing after birth on suckling and subsequent nursery and growing-finishing pig performance. The injectable Fe source used in both experiments was GleptoForte (Ceva Animal Health, LLC., Lenexa, KS). GleptoForte contains gleptoferron which is a Fe macromolecule complex. In Exp. 1, a total of 324 newborn pigs (DNA 241 × 600, initially 1.6 ± 0.04 kg body weight [BW]) within 27 litters were used. Two days after birth, all piglets were weighed, and six barrows and six gilts per litter were allotted to 1 of 6 treatments consisting of no Fe injection or 200 mg of injectable Fe provided in a single injection on d 2, 4, 6, 8, or 10 of age. Pigs were weaned (~21 d of age) and allotted to nursery pens with all pigs in each pen having received the same Fe treatment. In Exp. 2, a total of 1,892 newborn pigs (PIC 359 × C40; initially 1.5 ± 0.02 kg BW) within 172 litters were used. One day after birth, piglets were weighed, and 11 pigs within each litter were allotted to 1 of 6 treatments consisting of no Fe injection or 200 mg of injectable Fe provided on d 1, 3, 5, or 7 of age, or 200 mg on d 1 plus 200 mg on d 12 of age. Pigs were weaned (19 d of age) and placed in a commercial wean-to-finish facility in a total of 15 pens with equal representation of treatments in each pen. In both experiments, not providing an Fe injection after birth decreased (P < 0.05) preweaning average daily gain (ADG), weaning weight, and hemoglobin and hematocrit values compared with all other treatments. In Exp. 1, increasing the age that piglets received an Fe injection until 4 or 6 d after birth provided marginal evidence for an improvement (quadratic; P = 0.070) in preweaning ADG. For the nursery period, increasing the age that piglets received an Fe injection improved (quadratic; P = 0.013) d 80 BW, but there was no evidence of a difference (P > 0.10) in d 173 BW at the end of the grow-finish period. In Exp. 2, increasing the age that piglets received a 200 mg Fe injection showed no evidence of difference (P > 0.10) for subsequent nursery and growing-finishing ADG. In both experiments, hemoglobin and hematocrit values were decreased (linear; P < 0.05) at weaning with increasing age when pigs received an Fe injection. These experiments suggest that providing a 200 mg Fe injection within 7 d after farrowing is sufficient for optimizing preweaning and subsequent growth performance. 相似文献
909.
910.