Protocol: Non-antibiotic, alternative approaches to the nursery phase of swine production: a scoping review

It is widely accepted that antibiotic use drives the development of antibiotic resistance. Hence it is important that swine production uses antibiotics in a judicious manner. In addition, the label claim for livestock antibiotic growth promoters (AGP) of importance to humans has been removed in Canada. In reality, antibiotics have contributed greatly to efficiencies in meat production and animal health. A reduction in the use of growth promoting antibiotics has ramifications for costs of meat production and animal welfare given that sick animals need to be treated, often with antibiotics. Consequences of similar AGP bans in swine production in Europe included an immediate increase in therapeutic use of antibiotics considered important for humans, particularly for nursery stage pigs in Denmark and the Netherlands. It is important to identify and advance our knowledge through the existing research of alternative approaches to antibiotic use, in the nursery stage of pig production. Scoping reviews are a relatively novel approach for synthesizing research evidence in the veterinary and livestock production research literature (Pham MT., 2014). They are useful for mapping the extent, range, and nature of existing literature on a broad topic area. In addition, scoping reviews are useful for identifying gaps in the literature and for determining the feasibility of conducting one or more systematic reviews to help answer a specific question about the effectiveness of a specific intervention in a specific population measuring a specific outcome (Arksey and O’Malley, 2005)

The efficacy of antibiotics to prevent respiratory diseases in swine: A protocol for a systematic review

The treatment and prevention of infectious diseases in pigs is an important aspect of swine production worldwide. The prudent use of antimicrobials and other therapeutic drugs is a primary responsibility of swine producers and veterinarians and decisions surrounding the use of drug therapy include considerations such as cost, efficacy, and food safety. The World Health Organization has published numerous reports urging all stakeholders concerned with both food-producing animals and humans to establish recommended steps to enhance the prudent use of antimicrobials (WHO, 2015). Similarly, the Organization for Animal Health has also published recommendations and position statements regarding prudent use and risk management related to antimicrobial use in animals (OIE, 2017)

An evidence based ranking system for multiple studies designs for informing public policy. An example using interventions associated with Salmonella in swine.

Using the association between feed characteristics and Salmonella prevalence we will present an approach to combining data with multiple outcomes from multiple studies designs. The approach may be a method of informing policy makers in the area of food safety when a large amount of heterogeneous literature is available about a topic. The procedure for a systematic review of the literature was followed until the synthesis component. However, to combine the evidence we modified of the FDA Interim Evidence Ranking System for Scientific Information. Each study was characterized as one of 5 study design types based on evidentiary value. After classification by evidentiary value, the studies were considered collectively to rate the strength of the body of evidence based on quantity and consistency. The quantity ranking considered the number of studies, the number of individuals studied and generalizability to the target population. The consistency ranking considered whether studies with different designs reported similar findings. After ranking the body of evidence, an overall ranking was assigned for the strength of the evidence. The final ranking system had four levels. For example, the highest rank of scientific evidence, reflects a high level of comfort among qualified scientists that the association/relationship is scientifically valid. This level ranked relationship would be considered to have a very low probability of significant new data overturning the conclusion that the relationship is valid or significantly changing the nature of the relationship

Information retrieval for systematic reviews in food and feed topics: a narrative review

Introduction Systematic review methods are now being used for reviews of food production, food safety and security, plant health, and animal health and welfare. Information retrieval methods in this context have been informed by human healthcare approaches and ideally should be based on relevant research and experience. Objective This narrative review seeks to identify and summarise current research-based evidence and experience on information retrieval for systematic reviews in food and feed topics. Methods MEDLINE (Ovid), Science Citation Index (Web of Science) and ScienceDirect (http://www.sciencedirect.com/) were searched in 2012 and 2016. We also contacted topic experts and undertook citation searches. We selected and summarised studies reporting research on information retrieval, as well as published guidance and experience. Results There is little published evidence on the most efficient way to conduct searches for food and feed topics. There are few available study design search filters, and their use may be problematic given poor or inconsistent reporting of study methods. Food and feed research makes use of a wide range of study designs so it might be best to focus strategy development on capturing study populations, although this also has challenges. There is limited guidance on which resources should be searched and whether publication bias in disciplines relevant to food and feed necessitates extensive searching of the grey literature. Conclusions There is some limited evidence on information retrieval approaches, but more research is required to inform effective and efficient approaches to searching to populate food and feed reviews

Quantity and Distribution of Salmonella Recovered from Three Swine Lairage Pens

The quantity of Salmonella recoverable from three lairage pens in a swine abattoir was determined. Using dry four-ply cotton gauze pads measuring 10 by 10 cm, 100 fecal slurry samples were collected from each of the three pens. Salmonella recovery was expressed as the log CFU per milliliter of sample. Mean values were 2.5 log CFU/ml in pen A, 2.7 log CFU/ ml in pen B, and 0.89 log CFU/ml in pen C. Median values were 2.6 log CFU/ml in pen A, 2.0 log CFU/ml in pen B, and below the detectable limit in pen C. In pen C, Salmonella was not recoverable from a high number of samples. Pen B results suggested spatial dependency, i.e., samples close together were more similar than samples farther apart. These results indicate that Salmonella concentrations vary within and between lairage pens. Because of the limited number of pens assessed, it was not possible to identify factors that were associated with the observed variation in Salmonella concentrations within and between pens. However, this variation suggests that numerous samples are required to adequately describe the concentration of Salmonella in a lairage pen

The Association between Cleaning and Disinfection of Lairage Pens and the Prevalence of Salmonella enterica in Swine at Harvest

A series of four field trials were conducted to evaluate the ability of a cleaning and disinfection procedure in swine lairage pens to reduce the prevalence of Salmonella enterica in slaughtered pigs. A cleaning and disinfection procedure was applied to lairage pens at a large Midwest abattoir. Each trial consisted of a cleaned (alkaline chloride detergent) and disinfected (H2O2 plus peracetic acid sanitizer) pen (treated) and a control pen, each holding 90 to 95 pigs for 2 to 3 h before slaughter. Ileocecal lymph nodes, cecal contents, and rectal contents were collected from 45 pigs from each study pen at harvest and cultured for S. enterica. In all trials, cleaning and disinfection reduced the prevalence of S. enterica–positive floor swabs in the treated pen (P , 0.05). However, the postharvest prevalence of S. enterica–positive pigs varied between trials. In trial 1, there was no significant difference in the prevalence of S. enterica in pigs between treatment and control groups. In trials 2 and 3, the prevalence of S. enterica was higher in pigs from treated pens versus pigs from control pens (91% versus 40%, P , 0.0001, and 91% versus 24%, P , 0.0001, respectively). In trial 4, the prevalence of S. enterica was lower in pigs from treated pens compared with pigs from control pens (5% versus 42%, P , 0.0001). This study indicates that cleaning and disinfection effectively reduces the amount of culturable S. enterica in lairage pens, but the ability of cleaned and disinfected pens to reduce the prevalence of S. enterica in market-weight pigs remains inconclusive

The Sero-prevalence of Salmonella spp. in Finishing Swine in Iowa

This study represents the first attempt to classify Iowa production sites for Salmonella spp. sero-prevalence. The data suggest that the Iowa herds are similar in their distribution with respect to sero-prevalence of salmonella as Danish herds. Ignoring herd size, 91.2 of surveyed herds were negative or level 1, 8.2 % were level 2 herds, and 1.6 % level 3. These results are similar to previous Danish studies (Alban et al., 2002, Mousing et al., 1997). The current data suggests that larger herds tend to have a higher sero-prevalence than smaller units; however, formal analysis has yet to be conducted to determine the direct association between herd size and salmonella sero-prevalence. Studies by Carstensen et al. (1998) suggested that herd size was statistically associated, albeit weakly, with Salmonella sero-prevalence, but the authors concluded the relationship was probably not biologically significant

Interventions associated with feeding management practices and feed characteristics, and measures of Salmonella prevalence in live and slaughtered swine: A systematic review and summation of evidence

The aim of this review is to evaluate and summarize the evidence for associations between feeding management practices and feed characteristics, and Salmonella prevalence in swine, which may represent opportunities for interventions. Salmonella prevalence in the reviewed literature was measured either by culture or by the presence of antibodies. A systematic review of the area was conducted, the goal being to minimize the impact of bias. Systematic reviews include an assessment of the quality of studies and exclusion of studies that fail to meet standards for published material. The review evaluated evidence for an association between feed withdrawal from swine prior to slaughter, acidification of feed, heat treatment of feed, pellet vs. mash, course vs fine grind, and wet vs. dry. A large number of intervention studies were excluded from the review because they failed to report design features designed to limit the introduction of bias such as randomization and blinding. The majority of studies included were cross sectional studies, however these failed to provide strong evidence of an association because of the potential for confounding and the failure to document a temporal association between exposure to the risk factor and the outcome. The review concluded that title strongest body of work was available for pelleted feed and dry feed, however there was still uncertainty about the situations were this association may be effective. The conclusion was that there should be a low level of comfort among qualified scientists that the claimed association/relationship is scientifically valid. This ranking is primarily based on moderate to low quality studies, or insufficient numbers of tested individuals or herds, resulting in a low degree of confidence that results could be extrapolated to the target population

Vaccination against Salmonella and the association with measures of Salmonella prevalence in live and slaughtered swine - A systematic review

A systematic review was conducted to evaluate the effectiveness of vaccination to reduce Salmonella prevalence in market weight finisher swine. To identify relevant studies, online databases and selected conference proceedings were searched. Two reviewers independently assessed the relevance screening and methodological quality of studies. Data of characteristics of study population, intervention, outcome, statistical analysis, and results were extracted. Four clinical trials and 21 challenge studies were identified for the final review as they described vaccination to reduce Salmonella in swine Present evidence suggests that vaccination is associated with reduced Salmonella prevalence in swine

Determination of Toxoplasma gondii Antibody Prevalence in Midwest Market Swine

Pork has been identified as one of the food source(s) for human exposure to Toxoplasma gondii. This project was designed to determine the current prevalence of Toxoplasma gondii antibodies in the Midwestern USA market swine population. Test samples were selected, using random numbers generated from the Excel database, from approximately 2,500 daily meat juice samples submitted for Aujeszky’s Disease from eight Iowa abattoirs. Producer identification and lot size were recorded for each lot. Two hundred fifty samples were selected for 12 consecutive weeks – total of 15,014 samples. The presence of antibodies was determined using ELISA test kits by Safepath Laboratories. The prevalence for all samples was 0.75 % with a higher prevalence found in lots of 20 - 40 compared to 150 - 190 head. Additional on-farm evaluations of exposure risk factors are required to determine an association between sero-prevalence and lot size and to develop suitable prevention strategies