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A cross-sectional study was carried out to determine the seroprevalence and risk factors associated with bovine respiratory syncytial virus (BRSV) infection in non-vaccinated dairy and dual-purpose cattle herds from Ecuador. A total of 2,367 serum samples from 346 herds were collected from June 2008 to February 2009. A questionnaire, which included variables related to cattle, health, management measures, and the environment, was filled out in each herd. Presence of antibodies against BRSV was analyzed using a commercial indirect ELISA test. A logistic regression model was used to determine risk factors associated with BRSV at herd level. The individual seroprevalence against BRSV in non-vaccinated herds in Ecuador was 80.48% [1,905/2,367; 95% confidence interval (CI)?=?78.9-82.1]. The herd prevalence was 91.3% (316/346; 95% CI?=?88.3-94.3), and the intra-herd prevalence ranged between 25% and 100% (mean, 90.47%). The logistic regression model showed that the existence of bordering cattle farms, the dual-purpose farms, and the altitude of the farm (more than 2,338?m above sea level) were risk factors associated with BRSV infection. This is the first study about BRSV prevalence in Ecuador. It shows the wide spread of the BRSV infection in the country. The risk factors found will help to design effective control strategies.  相似文献   
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A cost model was developed to compare different implementation strategies of the new European Commission regulation for sheep and goat identification and registration (EC 21/2004) in Spain. Strategies were as follows: 1) conventional identification (CID) by two ear tags; 2) electronic identification (EID) by one bolus and one ear tag; and 3) mixed CID and EID strategy (MID), consisting of CID for fattening stock and EID for breeding stock. Complete and simplified implementations of the regulation were considered as options. Total costs per animal identified for all strategies and options varied according to the implementation option, ranging from Euros 2.48 and 4.64. The EID was the most expensive strategy (Euros 4.47 to 4.64) for all implementation options. Cost of CID and MID strategies ranged from Euros 2.63 to 2.98 and from Euros 2.48 to 3.03, respectively. The model was submitted to a sensitivity analysis without considering extra benefits of sheep and goat identification. Critical values for which the cost of MID equaled CID depended on strategy and option, and ranged from 7.5 to 11.5% for ear tag losses and from Euros 1.80 to 3.30 for bolus price. In conclusion, the use of a mixed strategy combining conventional ear tags (animals intended for slaughter) and electronic boluses (breeding stock) seems to be an affordable strategy that fulfills the European Commission regulation requirements for the identification of sheep and goats in Spain. Price reductions for devices and equipment would make the full electronic identification strategy less expensive in the future.  相似文献   
3.
Tropical Animal Health and Production - An extensive cross-sectional study to determine the seroprevalence of and associated risk factors for Brucella infection was performed in dairy and mixed...  相似文献   
4.
Hontoria  C.  Saa  A.  Almorox  J.  Cuadra  L.  Sánchez  A.  Gascó  J. M. 《Water, air, and soil pollution》2003,146(1-4):35-54
The present study examines the chemical characteristics of first-fraction precipitation samples collected over a period of one year in Madrid, and patterns of temporal and spatial variation observed in their composition. One hundred and sixty-four samples of wet precipitation collected on an event basis were analysed for anions, cations, pH and electrical conductivity. Precipitation in Madrid was neutral, with only 3% of samples showing pH < 5.6. Dominant ions were calcium andsulphates. Calcium was the principal neutralizing agent, explaining 64% of all nitrates and sulphates. The marine influence did not appear to be relevant, while the soil seemed to play an important role in the composition of precipitation. Precipitation chemistry displayed seasonal differences, with higher concentrations of sulphates and chloride in autumn and winter and of calcium and sodium in the summer. There was an inverse relationship between concentrations and sample volumes; while the correlation between concentrations and the time elapsedsince the last rain event was positive, though poor for normalized concentrations. Four variables (sample volume, days elapsed since the last rain event, maximum wind gust direction and season) explained to a large extent (more than 90% for some sampling stations) the variability of certain chemical variables.  相似文献   
5.
A cross-sectional study was carried out to determine the seroprevalence and risk factors associated to Bovine Herpesvirus 1 (BHV-1) infection in non-vaccinated dairy and dual purpose cattle herds from Ecuador. A total of 2367 serum samples from 346 herds were collected from June 2008 through February 2009. A questionnaire, which included variables related to cattle, health, management measures and environment was filled out in each herd. A commercial indirect ELISA test was used to determine the seropositivity against BHV-1. Generalized Estimating Equations (GEE) model was used to determine risk factors at individual level, including herd as random effect. The individual seroprevalence to BHV-1 in Ecuador was 43.2% (1023/2367; CI(??%): 41.2-45.2%). The herd prevalence was 82.1%; (284/346; CI(??%): 78.1-86.1%) and the intra-herd prevalence ranged from 12.5 to 100% (mean=64.1%). The GEE model showed that animal age (>4 years) (OR: 1.44; CI(??%): 1.18-1.75), BRSV infection (OR: 1.45; CI(??%): 1.09-1.92), altitude over the sea level (≤ 1800 m) (OR: 2.97; CI(??%): 2.1-4.22) and average slope (> 11%) (OR: 1.45; CI(??%): 1.07-1.95) are risk factors associated with BHV-1 infection, while a good cleaning of the facilities (OR: 0.66; CI(??%): 0.44-0.99) was shown to be a protective factor.  相似文献   
6.
A cross-sectional study was carried out to determine the seroprevalence and risk factors associated with Bovine viral diarrhea virus (BVDV) infection in non-vaccinated dairy and dual-purpose cattle herds from Ecuador. A total of 2,367 serum samples from 346 herds were collected from June 2008 through February 2009. A questionnaire, which included variables related to cattle, health, management measures, and the environment, was filled out in each herd. A commercial indirect enzyme-linked immunosorbent assay test was used to determine the seropositivity. A logistic regression model was used to determine risk factors at herd level. The individual seroprevalence for BVDV in non-vaccinated herds in Ecuador was 36.2% (857/2,367; CI95%, 34.3–38.1%). The herd prevalence was 74% (256/346; CI95%, 69.4–78.6%) and the intra-herd prevalence ranged between 11.1% and 100% (mean = 51.6%). The logistic regression model showed that the density of cattle farms in the area (more than 70%; OR, 1.94; CI95%, 1.21–3.2) and the altitude (higher than 2,338 m above sea level; 2.33; CI95%, 1.4–3.9) are potential risk factors associated with BVDV infection.  相似文献   
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