Impact of Raised without Antibiotics Measures on Antimicrobial Resistance and Prevalence of Pathogens in Sow Barns.

The growing concern over the emergence of antimicrobial resistance (AMR) in animal production as a result of extensive and inappropriate antibiotic use has prompted many swine farmers to raise their animals without antibiotics (RWA). In this study, the impact of implementing an RWA production approach in sow barns on actual on-farm antibiotic use, the emergence of AMR, and the abundance of pathogens was investigated. Over a 13-month period, fecal and nasopharynx samples were collected at 3-month intervals from sows raised in RWA barns and sows in conventional barns using antibiotics in accordance with the new regulations (non-RWA).

Piglet Gut and in-Barn Manure from Farms on a Raised without Antibiotics Program Display Reduced Antimicrobial Resistance but an Increased Prevalence of Pathogens.

In response to new stringent regulations in Canada regarding the use of antibiotics in animal production, many farms have implemented practices to produce animals that are raised without antibiotics (RWA) from birth to slaughter. This study aims to assess the impact of RWA production practices on reducing the actual total on-farm use of antibiotics, the occurrence of pathogens, and the prevalence of antimicrobial resistance (AMR). A 28-month longitudinal surveillance of farms that adopted the RWA program and conventional farms using antibiotics in accordance with the new regulations (non-RWA) was conducted by collecting fecal samples from 6-week-old pigs and composite manure from the barn over six time points and applying whole-genome sequencing (WGS) to assess the prevalence of AMR genes as well as the abundance of pathogens.

Greenhouse gases and performance of growing pigs fed wheat-based diets containing wheat millrun and a multi-carbohydrase enzyme.

The objective of this project was to determine the impact of feeding growing pigs with high wheat millrun diets supplemented with a multi-carbohydrase enzyme (amylase, cellulase, glucanase, xylanase, and invertase activities) on nutrient digestibility, growth performance, and greenhouse gas (GHG) output (carbon dioxide, CO2; nitrous oxide, N2O; methane, CH4). Three experiments were conducted utilizing six treatments arranged as a 3 × 2 factorial (0%, 15%, or 30% wheat millrun; with or without enzyme) for the digestibility experiment or as a 2 × 2 factorial (0% or 30% wheat millrun; with or without enzyme) for the performance and GHG experiments. The digestibility, performance, and GHG experiments utilized 48 individually housed pigs, 180 pigs housed 5 per pen, or 96 pigs housed 6 per chamber, respectively.

Control measures for airborne ammonia and respirable dust exposure in swine barns.

Extended exposure to airborne contaminants such as ammonia (NH) and respirable dust in swine facilities has been associated with various health problems among swine barn workers. The overall goal of this study was to assess the impact of selected control measures, namely, canola oil sprinkling, low crude protein diet, high level of cleaning, and manure pH manipulation, on NH and respirable dust concentrations in swine production rooms through area sampling and on worker exposure to these contaminants in accordance with National Institute of Occupational Safety and Health (NIOSH) methods for occupational exposure monitoring. Results from five trials showed that low crude protein diet can be used for reducing worker exposure to NH while oil sprinkling can be used for controlling respirable dust levels in swine rooms.

Occupational Exposure Risk for Swine Workers in Confined Housing Facilities.

Extended exposure of swine barn workers to noise and airborne contaminants has been reported to be associated with various health problems. In this study, the actual exposure of workers to respirable dust, gases (ammonia and hydrogen sulfide), and noise in swine production operations was monitored in order to determine the contribution of specific activities in the barn to potential adverse health impacts to swine workers. Selected workers in a swine barn facility were outfitted with a personal monitoring system that included a respirable dust sampler, ammonia (NH3) and hydrogen sulfide (H2S) gas monitors, and a noise dosimeter as they performed their regular duties during their workday.

Toll-like receptor 4 variants reduce airway response in human subjects at high endotoxin levels in a swine facility.

Background: Toll-like receptor 4 (TLR4) variants have been shown to reduce the respiratory responses to inhaled LPS in controlled experiments among healthy volunteers.

Objective: We sought to investigate whether naive subjects with TLR4 variants showed reduced respiratory response to a complex aerosol including endotoxin as a major constituent.

Methods: Twenty-nine nonsmoking, nonatopic healthy subjects with TLR4 299/399 polymorphisms and 29 age- and sex-matched, wild-type TLR4 control subjects were exposed for 5 hours each in a noncontaminated environment (baseline day) and in a swine confinement facility (exposure day).

Field comparison of inhalable and total dust samplers for assessing airborne dust in swine confinement barns.

Inhalable and total dust sampling devices were compared for evaluating airborne dust in swine confinement buildings. Measurements from three swine facilities (n = 77 paired means) were obtained by area sampling using the IOM (Institute of Occupational Medicine, Edinburgh, U.K.

Assessment of bioaerosols in swine barns by filtration and impaction.

Bioaerosol concentrations inside one naturally ventilated and one mechanically ventilated swine finishing barn were assessed by sampling air using membrane filtration and impaction (six-stage Andersen sampler), and assayed by culture method. The barns, located on the same commercial farm in northeast Kansas, did not show any significant difference (p > 0.05) in concentrations of total and respirable airborne microorganisms.