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991.
Abstract

Extract

An infectious epididymitis of rams caused by Brucella ovis (Buddie, 1956 Buddle, M. B. 1956. J. Hygiene, 54: 351351.  [Google Scholar]) infection, first described in Australia (Simmons and Boyes, 1953 Simmons, C. G. and Hall, W. J. K. 1953. Aust.vet.J., 29: 3333. [Crossref] [Google Scholar]) and New Zealand (Buddie and Boyes, 1953 Buddle, M. B. and Boyes, B. W. 1953. Aust.vet. J., 29: 145145. [Crossref] [Google Scholar]) was recognized subsequently in Czechoslovakia (Gdovin et al, 1955 Gdovin, T., Hrudka, F., Chladecky, E. and Koppel, Z. 1955. Shorn, ces. Akad. zemedelsk Ved., 28: 617617.  [Google Scholar]), the United States (McGowan and Shultz, 1956 McGowan, B. and Shultz, G. 1956. Cornel Vet., 46: 277277.  [Google Scholar]), South Africa (Van Rensburg et al, 1958 Van Rensburg, S. W. J., Van Heerden, K. M., Le Roux, D. J. and Snyders, A. J. 1958. J.S.Afr. vet. med. Ass., 29: 223223.  [Google Scholar]), Rumania (Tudoriu, et al, 1958 Tudoriu, C. D., Andrei, M., Draghici, D. and Moldoveanu, P. 1958. Anu. Inst. Pat.Igien. anim. Bucaresti, 8: 55.  [Google Scholar]), and South America (Dr Justo Zomara B, 1961, pers. comm.). As the infection can affect ram fertility and, further, can be responsible for abortion in ewes and perinatal mortality in lambs, attention has been directed to the development, evaluation, and application of control measures in a number of important sheep-raising countries.  相似文献   
992.
The aim of the present study was to evaluate the genetic and environmental factors affecting records of longissimus muscle area (LMA) and backfat thickness (BF) obtained between the 12th and 13th ribs, and rump fat thickness (RF) between the hook and pin bones, measured by real-time ultrasound in Nelore cattle. Also, weight records of 22,778 animals born from 1998 to 2003, in ten farms across six Brazilian states were used. Carcass traits as measured by ultrasound of the live animal were recorded from 2002 to 2004 in 2590 males and females with ages varying from 450 to 599 days. Fixed models including farm, year and season of birth, sex and type of feed effects, and the covariates age of dam (AOD) and age of animal at measurement were used to study the effect of environmental factors on these traits. The genetic parameters for LMA, BF and RF were estimated with two and three-trait animal models with 120-day weights using a restricted maximum likelihood method. All environmental effects significantly affected carcass traits, with the exception of year of birth for BF and RF and AOD for LMA. The heritability estimates for LMA, BF and RF were 0.35, 0.51 and 0.39, respectively. Standard errors obtained in one-trait analyses were from 0.07 to 0.09. Genetic correlation estimates between LMA and the two traits of subcutaneous fat were low (close to zero) and 0.74 between BF and RF, indicating that the selection for LMA should not cause antagonism in the genetic improvement of subcutaneous fat measured by real-time ultrasound.  相似文献   
993.
The use of a peroxidase labelled PCR generated probe followed by enhanced chemiluminescence hybridization assay detected infectious bursal disease virus directly from bursal imprints on a nylon membrane. Tissue imprint hybridization proved to be a simple, rapid and safe means of detecting IBD virus for screening large numbers of field samples. The PCR generated probe was highly specific for IBD virus and did not hybridize with cellular nucleic acids in control imprints. Tissue imprint hybridization was found to be a more sensitive method than conventional antigen detection assays.  相似文献   
994.
A cross-sectional coprological survey of liver flukes (Fasciola hepatica and Dicrocoelium dendriticum) was conducted on 81 bovine farms and 197 ovine farms with animals pasturing in an area (3971 km(2)) of the southern Italian Apennines. The farms were selected to be uniformly distributed throughout the study area using geographical information system (GIS) software. Between June 1999 and March 2000, faecal samples were collected from 975 cattle and 3940 sheep and examined using a modified McMaster technique. The results were subjected to statistical analysis and point distribution maps (PDMs) were drawn by GIS.Cattle of 9 of the 81 (11.1%) farms were positive for F. hepatica and of 43 (53.1%) for D. dendriticum. Sheep of 8 of the 197 (4.1%) farms were positive for F. hepatica and of 133 (67.5%) for D. dendriticum. Co-infection was found in cattle of 2 (2.5%) farms, and in sheep of 8 (4.1%) farms.The findings of the present survey show that D. dendriticum was the predominant liver fluke found in cattle and sheep with respect to egg count numbers for both farms and animals. In addition, the general trends of the PDMs show that D. dendriticum was widely and homogeneously spread throughout the study area, whereas F. hepatica was present only in a few concentrated zones of the study area that had both positive bovine and positive ovine farms.  相似文献   
995.
Avian pneumovirus (APV) or turkey rhinotracheitis virus (TRTV) is an important respiratory pathogen of domesticated poultry in many countries in Europe, Africa, and Asia. Until recently, the United States was considered free of APV. In late 1996, an atypical upper respiratory tract infection appeared in turkey flocks in Colorado and shortly thereafter in turkey flocks in Minnesota. An avian pneumovirus (APV-US) that was serologically distinct from the previously described TRTV was isolated as the primary cause of the new syndrome. The nucleotide sequence of a fragment of the APV-US fusion gene was determined and used to develop a polymerase chain reaction-based assay that specifically detects APV-US viral nucleic acid sequences in RNA extracts of tracheal swabs and turbinate homogenates. The assay is highly sensitive in that it can detect <0.01 TCID50 of APV. The availability of this assay enables the rapid and accurate determination of APV-US in infected poultry flocks.  相似文献   
996.
Radiation therapy of brain tumors in dogs typically involves administration of multiple fractions over several weeks. Fractionation is used to minimize damage to normal tissue. Radiosurgery uses multiple non-coplanar stereotactically focused beams of radiation in a series of arcs to deliver a single dose to the target with extreme accuracy. The large number of beams facilitates a high degree of conformation between the treatment area and the target tumor and allows for a steep dose gradient; the use of nonintersecting arcs minimizes exposure of normal tissue. Computed tomography with a stereotactic localizer secured to the skull allows generation of a 3-dimensional image of the target and provides accurate spatial coordinates for computerized treatment planning and delivery. Three dogs were treated with radiosurgery, using 1,000 to 1,500 cGy. A linear accelerator mounted on a rotating gantry was used to generate and deliver the radiation. Two dogs with meningiomas survived 227 and 56 weeks after radiosurgery. A dog with an oligodendroglioma survived 66 weeks. No complications were observed following the use of this technique.  相似文献   
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