title: Descriptive survey and Salmonella surveillance of pastured poultry layer farms in California.
abstract: While pasture-raised poultry comprises a small portion of the commercial poultry industry in North America, these alternative rearing systems have become increasingly popular. As such, it is critical to improve our understanding of husbandry practices and prevalence of zoonotic and epizoonotic diseases in these systems. This research reviews the results of a survey sent to 82 commercial pastured poultry farms in California. While the survey response was low (13.4%), it was enhanced by detailed in-person interviews and farm visits. In addition, we conducted drag swabs for Salmonella Enteritidis. On average, farms utilized 12.3% of their total farmland for pastured poultry operations, which often coexisted with other livestock (45%), touch crops (27%), and non-touch crops (45%). While the mean (44.6 sq. ft./hen) and median (22.2 sq. ft./hen) pasture stocking densities were within auditing guidelines, the mean (1.2 sq. ft./hen) and median (0.5 sq. ft./hen) coop stocking densities were below the pending USDA (2016) guidelines recommended in 7 CFR Part 205. Drag swab results showed the presence of Salmonella Enteritidis (SE) in the environment of one of the 11 farms (9.1%). In addition, Salmonella Pullorum (SP) whole blood agglutination tests were used to understand the prevalence of Salmonella spp. in laying hens within the studied farms. Results showed the presence of antibodies in flocks at six of the seven non-SE vaccinated farms, with a mean on-farm prevalence of 25.6% in laying hens. Logistic regression was used to determine risk factors for Group D Salmonella exposure in non-vaccinated flocks, using the SP blood agglutination data as the dependent variable and the survey questions as the independent variables. Statistically significant (P < 0.05) risk factors included exposed wire floors and flock size. These results improve our understanding of Salmonella prevalence and husbandry practices on commercial pastured poultry farms in California.
authors.affiliation: UC Davis College of Agriculture and Environmental Sciences, Geography Graduate Group, One Shields Ave., Davis, CA 95616, USA.
authors.forename: Naomi
authors.initials: N
authors.lastname: Dailey
authors.affiliation: UC Davis College of Engineering, Department of Civil & Environmental Engieering, One Shields Ave, Davis, CA 95616, USA.
authors.forename: Deb
authors.initials: D
authors.lastname: Niemeier
authors.affiliation: UC School of Veterinary Medicine, Poultry Health and Food Safety Epidemiology, One Shields Ave, Davis, CA 95616, USA.
authors.forename: Carine
authors.initials: C
authors.lastname: Elkhoraibi
authors.affiliation: California Animal Health and Food Safety Laboratory System-Turlock Branch, 1550 N. Soderquist Rd. P.O. Box 1522, Turlock, CA 93274, USA.
authors.forename: C Gabriel
authors.initials: CG
authors.lastname: Sentíes-Cué
authors.affiliation: UC Davis School of Veterinary Medicine, Department of Population Health and Reproduction, One Shields Ave, Davis, CA 95616, USA.
authors.forename: Maurice
authors.initials: M
authors.lastname: Pitesky
mesh_terms: D000822:Animal Husbandry; D000818:Animals; D002140:California / Q000453:epidemiology; D002645:Chickens; D005260:Female; D016015:Logistic Models; D011159:Population Surveillance; D011201:Poultry Diseases / Q000453:epidemiology* / Q000382:microbiology; D012307:Risk Factors; D012481:Salmonella Infections, Animal / Q000453:epidemiology* / Q000382:microbiology; D019779:Salmonella enterica / Q000502:physiology*; D012477:Salmonella enteritidis / Q000502:physiology*
keywords: Salmonella; husbandry; pastured poultry