Prevalence of and risk factors for bovine respiratory syncytial virus (BRSV) infection in non-vaccinated dairy and dual-purpose cattle herds in Ecuador.

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.

Seroprevalence and risk factors associated with bovine viral diarrhea virus (BVDV) infection in non-vaccinated dairy and dual purpose cattle herds in Ecuador.

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; CI(95%), 34.3-38.1%). The herd prevalence was 74% (256/346; CI(95%), 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; CI(95%), 1.21-3.2) and the altitude (higher than 2,338 m above sea level; 2.33; CI(95%), 1.4-3.9) are potential risk factors associated with BVDV infection.

Antimicrobial activity of five essential oils against origin strains of the Enterobacteriaceae family.

An in vitro assay measuring the antimicrobial activity of essential oils of Coridothymus capitatus (Spanish origanum), Satureja montana, Thymus mastichina (Spanish Origanum majorana), Thymus zygis (Spanish variety of Thymus vulgaris) and Origanum vulgare has been carried out against poultry origin strains of Escherichia coli, Salmonella enteritidis and Salmonella essen, and pig origin strains of enterotoxigenic E. coli (ETEC), Salmonella choleraesuis and Salmonella typhimurium. Using the broth microdilution method, all the essential oils showed an MIC > or = 2% (v/v) for the two strains of E. coli. The essential oil that showed the highest antimicrobial activity against the four strains of Salmonella was Origanum vulgare (MIC < or = 1% v/v), followed by Thymus zygis (MIC < or =2% v/v). Thymus mastichina inhibited all the microorganisms at the highest concentration, 4% (v/v), while the rest of the essential oils showed highly variable results. By chemotyping, higher inhibitory capacity was observed in the oils with a higher percentage of phenolic components (carvacrol and thymol) in comparison with oils containing the monoterpenic alcohol linalool. The results of this work confirm the antimicrobial activity of some essential oils, as well as their potential application in the treatment and prevention of poultry and pig diseases caused by salmonella.

Higher resistance of Campylobacter coli compared to Campylobacter jejuni at chicken slaughterhouse.

In order to compare the prevalence of Campylobacter coli and Campylobacter jejuni during the processing of broilers at slaughterhouse a total of 848 samples were analyzed during 2012 in southern Spain. Four hundred and seventy six samples were collected from cloaca, carcass surfaces and quartered carcasses. Moreover, 372 environmental swabs from equipment and scalding water were collected. Minimum inhibitory concentration (MIC) to ciprofloxacin, erythromycin, streptomycin, tetracycline and gentamicin was determined for isolates from chicken meat. The general prevalence of Campylobacter was 68.8% (40.2% of C. coli and 28.5% of C. jejuni). The relative prevalence of C. coli increased from loading dock area (41.5%) to packing area (64.6%). In contrast, the relative prevalence of C. jejuni decreased from 58.5% to 35.4%. These differences between species from initial to final area were significant (p=0.02). The highest antimicrobial resistance for C. jejuni and C. coli was detected to tetracycline (100%) and ciprofloxacin (100%), respectively. Campylobacter coli showed an antimicrobial resistance significantly higher than C. jejuni to streptomycin (p=0.002) and erythromycin (p<0.0001).

Prevalence and risk factors of Campylobacter infection in broiler flocks from southern Spain.

An extensive epidemiological study was performed to determine the prevalence and risk factors of Campylobacter infection in broiler farms in Andalusia (southern Spain). A total of 2221 cloacal swabs and 747 environmental swabs from 291 broiler flocks were screened between April 2010 and May 2012. The prevalence of Campylobacter in individual animals was 38.1%, and the flock prevalence was 62.9%. Flocks were predominantly infected by C. jejuni and C. coli but were also infected by untyped Campylobacter spp., and mixed-species infection could be found. Risk factors for Campylobacter infection were assessed from direct interview of the farmers. The number of positive samples by flock was modelled assuming a binomial distribution. Analysis indicated five factors associated with increased intra-flock prevalence: presence of dogs or cats on the farm, older age of the broiler flock, the application of thinning of flocks, the presence of windows with canvas blinds, and the presence of rodents in the poultry house. Two factors were associated with decreased intra-flock prevalence: the treatment of drinking water and having an entrance room for access into the poultry house. This is the first study performed on broilers farms from Spain reporting the risk factors of Campylobacter infection and is the largest study on the prevalence of Campylobacter infection.

Factors affecting the seroprevalence of lagovirus infection in wild rabbits (Oryctolagus cuniculus) in Southern Spain.

Cross-sectional studies were carried out on wild rabbit (Oryctolagus cuniculus) populations in Southern Spain to assess the prevalence of lagovirus infection and to identify potentially associated risk factors. A total of 619 blood and 487 liver samples from wild rabbits were collected from seven hunting areas with different Mediterranean ecosystems. Logistic regression analysis was used to assess associations between seropositivity and an extensive set of variables. The seroprevalence was 29.2% (95% CI: 25.6-32.8) and lagoviruses were not detected in liver samples. Logistic regression indicated that seropositivity to lagoviruses was associated with seropositivity to myxomatosis, wild rabbit density, the existence of artificial feeding sites, mean maximum monthly temperatures of 20-30 °C, and annual accumulated rainfall of >600 mm.

Seroprevalence and risk factors associated with Toxoplasma gondii in domestic pigs from Spain.

Serum samples from 2970 (1400 sows, 1570 fattening) pigs, from 100 farms in the 10 main swine production regions in Spain were tested for antibodies against T. gondii by the modified agglutination test (MAT). Antibodies to T. gondii (MAT 1:25 or higher) were detected in 492 pigs (16.6%, 9.7% in fattening pigs and 24.2% in sows). The herd prevalence was 85.0% (95% CI: 78-92) and within-farm prevalence ranged from 2.9% to 92.8% (median=17.6%). Statistically significant differences were observed among sampling regions with seroprevalence significantly higher in pigs from Valencia Community (27.3%), Extremadura (23.3%) and Catalonia (21.2%). A generalized estimating equations model indicated that the risk factors associated with T. gondii seroprevalence were: age, sows compared to fattening pigs (OR=2.9; 95% CI=1.83-4.53), lack of rodent control (OR=1.9; 95% CI=1.04-3.60) and presence of cats (OR=1.6; 95% CI=1.12-2.34). The seroprevalence observed in the present study indicates a widespread, although variable, exposure to T. gondii among domestic pigs in Spain, which might have important implications for public health. Management measures including control of rodents and cats on the farms could help to reduce the observed prevalence levels in Spain.