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Characterization of the temporal and spatial distribution and reproductive ratio of vesicular stomatitis outbreaks in Mexico in 2008
2011
Arroyo, Montserrat | Perez, Andres M. | Rodriguez, Luis L.
Objective--To characterize the temporal and spatial distribution and reproductive ratio of vesicular stomatitis (VS) outbreaks reported in Mexico in 2008. Procedures--The Poisson model of the space-time scan statistic was used to identify periods and geographical locations at highest risk for VS in Mexico in 2008. The herd reproductive ratio (Rh) of the epidemic was computed by use of the doubling-time method. Results--1 significant space-time cluster of VS was detected in the state of Michoacan from September 4 through December 10, 2008. The temporal extent of the VS outbreaks and the value and pattern of decrease of the Rh were different in the endemic zone of Tabasco and Chiapas, compared with findings in the region included in the space-time cluster. Conclusions and Clinical Relevance--The large number of VS outbreaks reported in Mexico in 2008 was associated with the spread of the disease from the endemic zone in southern Mexico to areas sporadically affected by the disease. Results suggested that implementation of a surveillance system in the endemic zone of Mexico aimed at early detection of changes in the value of Rh and space-time clustering of the disease could help predict occurrence of future VS outbreaks originating from this endemic zone. This information will help prevent VS spread into regions of Mexico and neighboring countries that are only sporadically affected by the disease.
اظهر المزيد [+] اقل [-]Molecular prevalence and species co-infection of bovine haemoparasites in Peninsular Malaysia
2017
Ibrahim A. R. | Maizatul A. M. | Chandrawathani P. | Jesse, F. F. A. | S. D., Ola-Fadunsin | Sani, R. A. | Amlizawathy A. | Sharma, R. S. K.
Bovine haemoparasites are cosmopolitan in distribution and are known to cause substantial losses to the cattle industry. In spite of their economic importance, there remains a dearth of information on their molecular epidemiology in many parts of the world including Malaysia. To ascertain the molecular prevalence and species co-infection of bovine haemoparasites in the country, blood samples were collected from 1,045 heads of beef and dairy cattle on 43 farms from six geographical zones throughout Peninsular Malaysia. Samples subjected to PCR amplification of parasite species-specific genetic fragments revealed that Anaplasma marginale was the most prevalent haemoparasite (72.6%),followed by Theileria orientalis(49.8%),Candidatus Mycoplasma haemobos ( 47. 0 % ),Babesia bovis(32. 5%), Babesia bigemina (30.5%) and Trypanosomaevansi(17.9%). A high percentage (92.1%) of cattle was infected with either one or more haemoparasites. Triple haemoparasite species co-infection was the most prevalent (25.6%), followed closely by double species co-infection (25.1%). The most common (8.8%) and significantly correlated(rs= 0.250; p<0.01) combination was A. marginale+ T.orientalis. The present study constitutes the first attempt in the country to document the molecular prevalence and species co-infection of bovine haemoparasites over a wide spatial distribution. The data obtained will facilitate treatment, control and prevention measures to improve the local cattle industry.
اظهر المزيد [+] اقل [-]Comparison of the width of the intervertebral disk space and radiographic changes before and after intervertebral disk fenestration in dogs
1991
Dallman, M.J. | Moon, M.L. | Giovannitti-Jensen, A.
Intervertebral disk space widths were measured on lateral radiographs of 73 anesthetized dogs. Weight was found to have a significant (P less than 0.01) effect on disk space width. Using weight-adjusted disk space width measurements for all subsequent studies, older (7- to 16-year-old) dogs and males had consistently, but not significantly, wider, disk spaces than did alternative groups. Cervical and lumbar intervertebral disk spaces tended to be wider than those in the caudal thoracic region. The widest cervical intervertebral disk spaces were C4-5 and C5-6 and the narrowest was C2-3. In the lumbar region, L2-3 was the widest disk space and L4-5 was the narrowest. Dachshunds generally had greater mean intervertebral disk space width than did other breeds of dogs. Cervical (n = 6 dogs) and thoracolumbar (n = 6 dogs) disk fenestration resulted in narrow intervertebral disk spaces, regardless of breed. When a ventral approach was used in thoracolumbar fenestration, the mean intervertebral disk space was narrower than that resulting from use of a dorsolateral approach. Spondylosis was found radiographically 1 to 4 years after intervertebral disk fenestration in 3 of 6 dogs that had cervical fenestrations and in 5 of 6 dogs that underwent thoracolumbar fenestration.
اظهر المزيد [+] اقل [-]Quantitative comparison of bone mineral density characteristics of the distal epiphysis of third metacarpal bones from Thoroughbred racehorses with or without condylar fracture
2016
Bogers, Sophie H. | Rogers, Chris W. | Bolwell, Charlotte | Roe, Wendi | Gee, Erica | Mcllwraith, Wayne
OBJECTIVE To compare regional proportions and spatial distributions of volumetric bone mineral density (BMDv) of the palmar aspect of the distal epiphysis of the third metacarpal bone (McIII) in limbs with or without a condylar fracture from Thoroughbred racehorses. SAMPLE McIIIs from cadavers of Thoroughbred racehorses with (n = 6 bones) and without (8) a condylar fracture. PROCEDURES BMDv and spatial distributions of BMDv in peripheral quantitative CT images of the distal epiphysis of McIIIs were quantitatively assessed with spatial analysis software. Relative proportions of voxels within 9 threshold categories of BMDv and spatial statistics for BMDv distribution were compared between fractured and nonfractured limbs. RESULTS No significant differences in BMDv characteristics were identified between fractured and nonfractured limbs, although fractured limbs had a lower proportion of voxels in the BMDv thresholds 700 to < 800 mg/cm3 and 800 to < 900 mg/cm3 but a higher proportion of voxels in the BMDv threshold 1,000 to < 1,100 mg/cm3 for the central condylar region of the medial condyle. Results of spatial analysis reflected the response of bone to race training rather than differences between fractured and nonfractured limbs. In both limb groups, uniform clusters of low BMDv with areas of high BMDv were identified. CONCLUSIONS AND CLINICAL RELEVANCE BMDv characteristics of the distal epiphysis of McIII reflected training load, and fracture characteristics were subtle. Serial imaging techniques in conjunction with detailed training data are required to elucidate the onset of the pathological response to load in horses.
اظهر المزيد [+] اقل [-]Evaluation of economic effects and the health and performance of the general cattle population after exposure to cattle persistently infected with bovine viral diarrhea virus in a starter feedlot
2009
To evaluate economic effects and health and performance of the general cattle population after exposure to cattle persistently infected (PI) with bovine viral diarrhea virus (BVDV) in a feedlot. 21,743 high-risk calves from the southeastern United States. PI status was determined by use of an antigen-capture ELISA (ACE) and confirmed by use of a second ACE, reverse transcriptase-PCR assay of sera, immunohistochemical analysis, and virus isolation from sera. Groups with various amounts of exposure to BVDV PI cattle were used. After being placed in the feedlot, identified PI cattle were removed from 1 section, but PI cattle remained in another section of the feedlot. Exposure groups for cattle lots arriving without PI animals were determined by spatial association to cattle lots, with PI animals remaining or removed from the lot. 15,348 cattle maintained their exposure group. Performance outcomes improved slightly among the 5 exposure groups as the risk for exposure to BVDV PI cattle decreased. Health outcomes had an association with exposure risk that depended on the exposure group. Comparing cattle lots with direct exposure with those without direct exposure revealed significant improvements in all performance outcomes and in first relapse percentage and mortality percentage in the health outcomes. Economic analysis revealed that fatalities accounted for losses of $5.26/animal and performance losses were $88.26/animal. This study provided evidence that exposure of the general population of feedlot cattle to BVDV PI animals resulted in substantial costs attributable to negative effects on performance and increased fatalities.
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