Watch your language: An exploration of the use of causal wording in veterinary observational research.

Observational research may be conducted to predict an outcome or to identify associations between an intervention or risk factor (an "exposure") and an outcome. However, the end goal of observational research often is to identify exposures that can be manipulated to improve an outcome, meaning that the aim is identify causal relationships. Causal inference from observational studies may be appropriate when an exposure-outcome of interest is identified, causal reasoning is used to identify confounders, confounders are adequately controlled, and theoretical issues, such as temporality, are considered. If these conditions are not met, causal inference cannot be made in an observational study. The objective of our study was to explore the use of causal language in veterinary observational studies, and to compare the use of causal language between studies that appear to be predictive or associational in purpose vs. those that appear to be exploring causal relationships. The dataset comprised 200 observational studies in veterinary species published between 2020 and 2022. The majority (117 out of 200) were cross-sectional studies. There were 48 studies that described an exposure-outcome of interest, and we considered these studies to be exploring potential causal relationships; of note, this liberal categorization would be anticipated to overestimate the proportion of studies suitably designed for causal inference. Overall, 172 studies (86%) used causal wording in at least one section of the article. Causal language was used in 128/152 (84%) of studies exploring predictions or associations; this language implies causation when it is not appropriate to do so. In studies designed such that causal inference might be possible, 44/48 (92%) used causal language in one or more sections. There were no substantive differences in the use of causal wording between observational study designs, exposure types, or whether the first author's affiliation was a country in which English is an official language. There is a need for authors of veterinary observational studies to explicitly state the purpose of the study (associational, predictive, or causal), and to use causal wording appropriately based on the aim of the study.

Publication and accessibility of results of controlled trials in dairy science.

Research allows for the discovery of new knowledge and is integral to evidence-based decision-making. However, research is only useful if it is available. The aim of this study was to explore publication and accessibility of full-text reports for controlled trials (experimental studies) conducted in dairy cattle. We determined the proportion of controlled trials presented as abstracts at the 2015 Joint Annual Meeting of the American Dairy Science Association and the American Society of Animal Science or the 2015 American Association of Bovine Practitioners Annual Conference that were subsequently published. Factors associated with publication or non-publication in a peer-reviewed journal were evaluated using risk ratios. For trials that were subsequently published, we compared the sample size, numerical results, and inference between the conference abstract and the subsequent publication. Approximately half of the trials (177 out of 380) reported at conferences were subsequently published. Source conference, whether the conference abstract results were described as preliminary, whether there was at least one positive outcome, author affiliation, whether the trial involved deliberate disease induction, and total sample size were not strongly associated with subsequent publication. For trials that were published, the sample size differed between the conference proceedings and full publications for 22%, the numerical results differed in 29%, and the inference differed for 11%. We also evaluated whether trials included in 9 recent systematic reviews were in English and were available without subscription or cost. Of the 390 trials included in recent systematic reviews, approximately 40% were available only through subscription or access fee. These results suggest that publication and accessibility of research results is suboptimal, representing an area of wastage in dairy cattle research. Researchers should ensure that they publish the results of trials comprehensively in searchable publications, even if the results are not novel or do not detect expected differences, and, when possible, make the results available freely.

Salmonella in Animal Feeds: A Scoping Review.

The objective of this study was to describe the volume and nature of published literature on Salmonella in animal feeds using a formal scoping review methodology. A structured search followed by eligibility screening resulted in the identification of 547 relevant studies, encompassing studies conducted in the fields in which animal feeds are grown (15 studies), the manufacturing sector (106), during transportation (11), in the retail sector (15), and on-farm (226), with the sector not described for 204 studies. The most common study purposes were to estimate the prevalence of Salmonella in animal feeds (372 studies) and to identify serovars (195). The serovars that were found in animal feeds included serovars associated with human illness, with animal illness, and with serovars identified in food (livestock and poultry) intended for human consumption. There were 120 intervention studies and 83 studies conducted to evaluate potential risk factors. Within intervention and risk factor studies, there may be sufficient depth to warrant synthesis research in the areas of heat interventions, fermentation and ensiling, organic acids, season, and geographic region. Some deficiencies were identified in the completeness of reporting of key features in the relevant studies.

Quality of reporting of clinical trials in dogs and cats: An update.

BACKGROUND: Comprehensive reporting of clinical trials is essential to allow the trial reader to evaluate the methodological rigor of the trial and interpret the results. Since publication of the updated Consolidated Standards of Reporting Trials (CONSORT) guidelines for reporting of parallel clinical trials in humans, extensions for reporting of abstracts and crossover trials have been published. OBJECTIVES: To describe the types of trials using dogs and cats published from 2015 to 2020 and to evaluate the quality of reporting of a sample of recently published parallel and crossover trials. ANIMALS: None. METHODS: A comprehensive search was conducted to identify parallel or crossover design clinical trials using dogs and cats published from January 1, 2015 onwards. Quality of reporting was evaluated on a subset of trials published during 2019. The reporting of items recommended in the CONSORT reporting guidelines for abstracts, parallel trials, and crossover trials was evaluated independently by 2 reviewers using standardized forms created for this study. Disagreements among reviewers were resolved by consensus. Results were tabulated descriptively. RESULTS: The frequency of reporting of trial features varied from low to high. There remain deficiencies in the quality of reporting of key methodological features and information needed to evaluate and interpret trial results. CONCLUSIONS AND CLINICAL IMPORTANCE: There is still a need for authors, peer-reviewers, and editors to follow reporting guidelines such as CONSORT to maximize the value of clinical trials and to increase confidence in the validity of the trial results.

Reporting and analysis of repeated measurements in preclinical animals experiments.

A common feature of preclinical animal experiments is repeated measurement of the outcome, e.g., body weight measured in mice pups weekly for 20 weeks. Separate time point analysis or repeated measures analysis approaches can be used to analyze such data. Each approach requires assumptions about the underlying data and violations of these assumptions have implications for estimation of precision, and type I and type II error rates. Given the ethical responsibilities to maximize valid results obtained from animals used in research, our objective was to evaluate approaches to reporting repeated measures design used by investigators and to assess how assumptions about variation in the outcome over time impact type I and II error rates and precision of estimates. We assessed the reporting of repeated measures designs of 58 studies in preclinical animal experiments. We used simulation modelling to evaluate three approaches to statistical analysis of repeated measurement data. In particular, we assessed the impact of (a) repeated measure analysis assuming that the outcome had non-constant variation at all time points (heterogeneous variance) (b) repeated measure analysis assuming constant variation in the outcome (homogeneous variance), (c) separate ANOVA at individual time point in repeated measures designs. The evaluation of the three model fitting was based on comparing the p-values distributions, the type I and type II error rates and by implication, the shrinkage or inflation of standard error estimates from 1000 simulated dataset. Of 58 studies with repeated measures design, three provided a rationale for repeated measurement and 23 studies reported using a repeated-measures analysis approach. Of the 35 studies that did not use repeated-measures analysis, fourteen studies used only two time points to calculate weight change which potentially means collected data was not fully utilized. Other studies reported only select time points (n = 12) raising the issue of selective reporting. Simulation studies showed that an incorrect assumption about the variance structure resulted in modified error rates and precision estimates. The reporting of the validity of assumptions for repeated measurement data is very poor. The homogeneous variation assumption, which is often invalid for body weight measurements, should be confirmed prior to conducting the repeated-measures analysis using homogeneous covariance structure and adjusting the analysis using corrections or model specifications if this is not met.

The study design elements employed by researchers in preclinical animal experiments from two research domains and implications for automation of systematic reviews.

Systematic reviews are increasingly using data from preclinical animal experiments in evidence networks. Further, there are ever-increasing efforts to automate aspects of the systematic review process. When assessing systematic bias and unit-of-analysis errors in preclinical experiments, it is critical to understand the study design elements employed by investigators. Such information can also inform prioritization of automation efforts that allow the identification of the most common issues. The aim of this study was to identify the design elements used by investigators in preclinical research in order to inform unique aspects of assessment of bias and error in preclinical research. Using 100 preclinical experiments each related to brain trauma and toxicology, we assessed design elements described by the investigators. We evaluated Methods and Materials sections of reports for descriptions of the following design elements: 1) use of comparison group, 2) unit of allocation of the interventions to study units, 3) arrangement of factors, 4) method of factor allocation to study units, 5) concealment of the factors during allocation and outcome assessment, 6) independence of study units, and 7) nature of factors. Many investigators reported using design elements that suggested the potential for unit-of-analysis errors, i.e., descriptions of repeated measurements of the outcome (94/200) and descriptions of potential for pseudo-replication (99/200). Use of complex factor arrangements was common, with 112 experiments using some form of factorial design (complete, incomplete or split-plot-like). In the toxicology dataset, 20 of the 100 experiments appeared to use a split-plot-like design, although no investigators used this term. The common use of repeated measures and factorial designs means understanding bias and error in preclinical experimental design might require greater expertise than simple parallel designs. Similarly, use of complex factor arrangements creates novel challenges for accurate automation of data extraction and bias and error assessment in preclinical experiments.

The reporting characteristics of bovine respiratory disease clinical intervention trials published prior to and following publication of the REFLECT statement.

The goal of the REFLECT Statement (Reporting guidElines For randomized controLled trials in livEstoCk and food safeTy) (published in 2010) was to provide the veterinary research community with reporting guidelines tailored for randomized controlled trials for livestock and food safety. Our objective was to determine the prevalence of REFLECT Statement reporting of items 1-19 in controlled trials published in journals between 1970 and 2017 examining the comparative efficacy of FDA-registered antimicrobials against naturally acquired BRD (bovine respiratory disease) in weaned beef calves in Canada or the USA, and to compare the prevalence of reporting before and after 2010, when REFLECT was published. We divided REFLECT Statement, items 3, 5, 10, and 11 into subitems, because each dealt with multiple elements requiring separate assessment. As a result, 28 different items or subitems were evaluated independently. We searched MEDLINE® and CABI (CAB Abstracts® and Global Health®) (Web of Science™) in April 2017 and screened 2327 references. Two reviewers independently assessed the reporting of each item and subitem. Ninety-five references were eligible for the study. The reporting of the REFLECT items showed a point estimate for the prevalence ratio >1 (i.e. a higher proportion of studies published post-2010 reported this item compared to studies published pre-2010), apart from items 10.3, i.e., item 10, subitem 3 (who assigned study units to the interventions), 13 (the flow of study units through the study), 16 (number of study units in analysis), 18 (multiplicity), and 19 (adverse effects). Fifty-three (79%) of 67 studies published before 2010 and all 28 (100%) papers published after 2010 reported using a random allocation method in either the title, abstract, or methods (Prevalence ratio = 1.25; 95% CI (1.09,1.43)). However, 8 studies published prior to 2010 and 7 studies published post-2010 reported the term "systematic randomization" or variations of this term (which is not true randomization) to describe the allocation procedure. Fifty-five percent (37/67) of studies published pre-2010 reported blinding status (blinded/not blinded) of outcome assessors, compared to 24/28 (86%) of studies published post-2010 (Prevalence ratio = 1.5, 95% CI (1.19, 2.02)). The reporting of recommended items in journal articles in this body of work is generally improving; however, there is also evidence of confusion about what constitutes a random allocation procedure, and this suggests an educational need. As this study is observational, this precludes concluding that the publication of the REFLECT Statement was the cause of this trend.

Authors' response to comments from Nachman KE et al.

Authors' response to comments letter to the editor from Nachman KE et al.

Updated systematic review: associations between proximity to animal feeding operations and health of individuals in nearby communities.

OBJECTIVE: The objective of this review was to update a systematic review of associations between living near an animal feeding operation (AFO) and human health. METHODS: The MEDLINE® and MEDLINE® In-Process, Centre for Agricultural Biosciences Abstracts, and Science Citation Index databases were searched. Reference lists of included articles were hand-searched. Eligible studies reported exposure to an AFO and an individual-level human health outcome. Two reviewers performed study selection and data extraction. RESULTS: The search returned 3702 citations. Sixteen articles consisting of 10 study populations were included in the analysis. The health outcomes were lower and upper respiratory tracts, MRSA, other infectious disease, neurological, psychological, dermatological, otologic, ocular, gastrointestinal, stress and mood, and other non-infectious health outcomes. Most studies were observational and used prevalence measures of outcome. An association between Q fever risk and proximity to goat production was reported. Other associations were unclear. Risk of bias was serious or critical for most exposure-outcome associations. Multiplicity (i.e., a large number of potentially correlated outcomes and exposures assessed on the same study subjects) was common in the evidence base. CONCLUSIONS: Few studies reported an association between surrogate clinical outcomes and AFO proximity for respiratory tract-related outcomes. There were no consistent dose-response relationships between surrogate clinical outcome and AFO proximity. A new finding was that Q fever in goats is likely associated with an increased Q fever risk in community members. The review results for the non-respiratory health outcomes were inconclusive because only a small number of studies were available or the between-study results were inconsistent. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42014010521.

Systematic review of the magnitude of change in prevalence and quantity of Salmonella after administration of pathogen reduction treatments on pork carcasses.

OBJECTIVE: In this systematic review, we summarized change in Salmonella prevalence and/or quantity associated with pathogen reduction treatments (washes, sprays, steam) on pork carcasses or skin-on carcass parts in comparative designs (natural or artificial contamination). METHODS: In January 2015, CAB Abstracts (1910-2015), SCI and CPCI-Science (1900-2015), Medline® and Medline® In-Process (1946-2015) (OVIDSP), Science.gov, and Safe Pork (1996-2012) were searched with no language or publication type restrictions. Reference lists of 24 review articles were checked. Two independent reviewers screened 4001 titles/abstracts and assessed 122 full-text articles for eligibility. Only English-language records were extracted. RESULTS: Fourteen studies (5 in commercial abattoirs) were extracted and risk of bias was assessed by two reviewers independently. Risk of bias due to systematic error was moderate; a major source of bias was the potential differential recovery of Salmonella from treated carcasses due to knowledge of the intervention. The most consistently observed association was a positive effect of acid washes on categorical measures of Salmonella; however, this was based on individual results, not a summary effect measure. CONCLUSION: There was no strong evidence that any one intervention protocol (acid temperature, acid concentration, water temperature) was clearly superior to others for Salmonella control.

The effectiveness of selected feed and water additives for reducing Salmonella spp. of public health importance in broiler chickens: a systematic review, meta-analysis, and meta-regression approach.

Eating inappropriately prepared poultry meat is a major cause of foodborne salmonellosis. Our objectives were to determine the efficacy of feed and water additives (other than competitive exclusion and antimicrobials) on reducing Salmonella prevalence or concentration in broiler chickens using systematic review-meta-analysis and to explore sources of heterogeneity found in the meta-analysis through meta-regression. Six electronic databases were searched (Current Contents (1999-2009), Agricola (1924-2009), MEDLINE (1860-2009), Scopus (1960-2009), Centre for Agricultural Bioscience (CAB) (1913-2009), and CAB Global Health (1971-2009)), five topic experts were contacted, and the bibliographies of review articles and a topic-relevant textbook were manually searched to identify all relevant research. Study inclusion criteria comprised: English-language primary research investigating the effects of feed and water additives on the Salmonella prevalence or concentration in broiler chickens. Data extraction and study methodological assessment were conducted by two reviewers independently using pretested forms. Seventy challenge studies (n=910 unique treatment-control comparisons), seven controlled studies (n=154), and one quasi-experiment (n=1) met the inclusion criteria. Compared to an assumed control group prevalence of 44 of 1000 broilers, random-effects meta-analysis indicated that the Salmonella cecal colonization in groups with prebiotics (fructooligosaccharide, lactose, whey, dried milk, lactulose, lactosucrose, sucrose, maltose, mannanoligosaccharide) added to feed or water was 15 out of 1000 broilers; with lactose added to feed or water it was 10 out of 1000 broilers; with experimental chlorate product (ECP) added to feed or water it was 21 out of 1000. For ECP the concentration of Salmonella in the ceca was decreased by 0.61 log(10)cfu/g in the treated group compared to the control group. Significant heterogeneity (Cochran's Q-statistic p≤0.10) was observed among studies examining all organic acids (controlled or challenge experiments), butyric acid, formic acid, a formic/propionic acid mixture, fermented liquid feed, and D-mannose. Meta-regressions were conducted to examine the source of heterogeneity among studies. For prevalence outcomes, 36% and 60% of the total variance was within and between studies, respectively. For concentration outcomes, 39% and 33% of the total variance was within and between studies, respectively. Inadequate blinding and randomization was common, and no studies undergoing meta-analysis or meta-regression were conducted on a commercial farm. The strength of evidence of the effect of these additives was very low. Studies conducted under commercial conditions are needed to understand the potential benefit of these interventions for the poultry industry and to improve the strength of evidence of the effectiveness of these additives.

Completeness of reporting in abstracts from clinical trials of pre-harvest interventions against foodborne pathogens.

Abstracts are the most commonly read part of a journal article, and play an important role as summaries of the articles, and search and screening tools. However, research on abstracts in human biomedicine has shown that abstracts often do not report key methodological features and results. Little research has been done to examine reporting of such features in abstracts from papers detailing pre-harvest food safety trials. Thus, the objective of this study was to assess the quality of reporting of key factors in abstracts detailing trials of pre-harvest food safety interventions. A systematic search algorithm was used to identify all in vivo trials of pre-harvest interventions against foodborne pathogens in PubMed and CAB Direct published from 1999 to October 2009. References were screened for relevance, and 150 were randomly chosen for inclusion in the study. A checklist based on the CONSORT abstract extension and the REFLECT Statement was used to assess the reporting of methodological features and results. All screening and assessment was performed by two independent reviewers with disagreements resolved by consensus. The systematic search returned 3554 unique citations; 356 were found to be relevant and 150 were randomly selected for inclusion. The abstracts were from 51 different journals, and 13 out of 150 were structured. Of the 124 abstracts that reported whether the trial design was deliberate disease challenge or natural exposure, 113 were deliberate challenge and 11 natural exposure. 103 abstracts detailed studies involving poultry, 20 cattle and 15 swine. Most abstracts reported the production stage of the animals (135/150), a hypothesis or objective (123/150), and results for all treatment groups (136/150). However, few abstracts reported on how animals were grouped in housing (25/150), the location of the study (5/150), the primary outcome (2/126), level of treatment allocation (15/150), sample size (63/150) or whether study units were lost to follow up (4/150). Forty-eight (48/150) abstracts reported the name, mode of administration, dose and duration of the intervention(s), while 102 (102/150) reported at least one of these elements. Nine (9/150) abstracts specified that allocation of study units to treatments was randomized, and none of the abstracts reported whether blinding was used (0/150). These results reveal gaps in reporting of methodological features and results. Thus, improving reporting quality in abstracts should be a crucial goal to be pursued by authors, reviewers and journal editors.

A systematic review-meta-analysis of chilling interventions and a meta-regression of various processing interventions for Salmonella contamination of chicken.

CONTEXT: The results of individual studies investigating the efficacy of chilling and other processing interventions on Salmonella prevalence or concentration in broiler chicken carcasses are inconsistent or contradictory. OBJECTIVE: Determine efficacy of chilling on reducing Salmonella prevalence or concentration on broiler carcasses using systematic review-meta-analysis, and explore sources of heterogeneity among studies investigating various processing interventions through meta-regression. DATA SOURCES: A comprehensive search included electronic search in six databases, manual search of reference lists of topic-related articles, and consultation with five topic experts to assure that all relevant intervention research was identified. STUDY INCLUSION: Primary intervention research, published in English, encompassing control, challenge, cohort, or before-and-after study designs investigating the efficacy of any chilling or other processing interventions on Salmonella prevalence or concentration in broiler chicken carcasses. RISK OF BIAS ASSESSMENT AND DATA EXTRACTION: Data pertaining to study methodology and reported results, chilling or other processing intervention parameters, populations sampled and outcomes measured were assessed for methodological soundness and extracted by two independent reviewers using pretested checklists. RESULTS: Random-effects meta-analyses of immersion chilling with chlorine (n=9 trials), acetic acid (n=16) and potable water (n=13) trended towards reductions in the odds or log(10)CFU/ml of Salmonella. Significant heterogeneity (P-value≤0.1 and I(2)>25%) precluded the reporting of pooled summary effect estimates. Meta-regression of all processing interventions indicated that serotype, disinfectant type and treatment time and pH were significantly associated with studies reporting reductions in concentration while study design, population sampled, study setting, publication date, intervention and disinfectant type, and treatment pH were significantly associated with studies reporting reductions in prevalence. Methodological and reporting flaws were consistently observed in relevant intervention research as well as a lack of studies conducted under commercial conditions and using Salmonella concentration outcomes. CONCLUSIONS: Chilling may be effective at reducing Salmonella concentration and prevalence, but significant heterogeneity precluded reporting of pooled summary effect estimates for many chilling interventions. Investigations into potential sources of heterogeneity among all processing interventions found that the use of other chemical disinfectants, such as organic acids and surfactants might result in larger reductions in Salmonella contamination than more commonly utilized oxidizing agents like chlorine.

Stray dog population health in Jodhpur, India in the wake of an animal birth control (ABC) program.

Our objectives were to (1) estimate the prevalence of various health indices in the stray dog population in Jodhpur, India and (2) determine if there was an association between an animal birth control (ABC) program and the prevalence of these health indices in this population. A prevalence survey of 323 sexually intact stray dogs >3 months caught from the streets of Jodhpur from September to November, 2005 indicated that low body condition score (70%), skin conditions (69%) and tick infestation (68%) were the most common health problems in this population. An observational study of 888 stray dogs on the streets of Jodhpur from March to April, 2006 revealed that sterilized dogs were more likely to have a higher body condition score (BCS) than sexually intact dogs when controlling for age, based on a multinomial regression model. However, sterilized dogs were more likely to have a skin condition than sexually intact dogs, based on a logistic regression model. Our observations of the surgical/kennel facility indicated that an effective tick control program was needed. Additionally, the current parasite control protocol at the kennel/shelter facility was inadequate to treat mange, a contact-transmitted skin disease. This is the first study to evaluate the associations between an ABC program and stray dog health, apart from rabies.

Stray dog population demographics in Jodhpur, India following a population control/rabies vaccination program.

Animal Birth Control (ABC) is a program by which stray dogs are sterilized and vaccinated against rabies with the aim of controlling both dog population size and rabies. Population size and demographics of stray dogs were measured before and after implementation of an ABC program in Jodhpur, India. Dog population size declined (p<0.05) in three of five areas surveyed, showed a decreasing trend (p>0.05) in 1 area, and remained stable in 1 area between 2005 and 2007. By 2007, 61.8-86.5% of the free-roaming dog population was surgically sterilized and vaccinated for rabies in the areas surveyed. In March-May, 2007, adults comprised 80-96% of the free-roaming dog population, while subadults and puppies comprised 0-18 and 0-4%, respectively. The male:female ratio among dogs>3 months old was 1.4:1. A population demographic model predicted that at the current level of sterilization/rabies vaccination, vaccination coverage would remain above 70%, and the dog population would decrease by 69% reaching stability after 13-18 years. A surgical sterilization coverage under 40% would maintain the dog population at current levels.

Comparison of outcomes and other variables between conference abstracts and subsequent peer-reviewed papers involving pre-harvest or abattoir-level interventions against foodborne pathogens.

Accuracy in the reporting of studies in conference abstracts is important because the majority of studies in such abstracts are never further detailed in peer-reviewed publications, and data from such abstracts may be used in systematic reviews. Previous research on interventional studies in human biomedicine indicates that there is no guarantee of consistency between a conference abstract and paper in the reporting of results and other key variables. However, no research has been done to determine if this lack of reporting consistency in abstracts and papers extends to interventional studies in pre-harvest/harvest-level food safety. The goal of this study was to compare outcome results and other key variables between conference abstracts and subsequent peer-reviewed publications describing studies of pre-harvest and abattoir-level interventions against foodborne pathogens, and to determine whether the agreement in the results or key variables was associated with the time to full publication. A systematic search identified 59 conference abstracts with matching peer-reviewed papers (matches), and data on variables including outcome measures and results, pathogens, species, interventions, overall efficacy of intervention, sample size and housing were extracted from both the conference abstracts and the papers. The matching of variables between abstracts and papers was described, and logistic regression used to test for associations between variable matching and time to publication. Sample size was only provided for both abstract and paper in 24 matches; the same sample size was reported in 20 of these matches. Most other variables were reported in the majority of abstracts/papers, and with the exception of outcomes and intervention effect, the reporting of variables was relatively consistent. There was no significant difference in the numbers of authors, with the first author the same in 78.3% of matches. Of 231 outcome measures reported in both abstracts and papers, nearly one third (77% or 32.2%) had different results, with 32 changing direction of effect. More than a quarter of matches involved at least one significant change in outcome result. The overall conclusion on the efficacy of the intervention changed in 10.7% of matches. There was a significant association between increased time to publication and differences in the number of authors, and having fewer outcome measures in the abstract reported in the paper. These results suggest that data from conference abstracts should be considered with caution.

Assessing reproductive patterns and disorders in free-ranging dogs in Jodhpur, India to optimize a population control program.

The objectives were to test the hypothesis that estrus and pregnancy are seasonal in free-ranging female dogs (>3 mo old) in Jodhpur, India, and to determine litter size, and the prevalence of fetal resorption in this population. The prevalence of estrus and pregnancy was determined in 5400 free-ranging bitches (trapped and released) at the time of ovariohysterectomy. In a separate study, the uteri and ovaries of 246 free-ranging bitches were examined to determine litter size and fetal resorption. The bitches exhibited seasonal estrus and pregnancy (P < 0.00001), with a higher percentage of bitches in estrus or pregnant during the late monsoon season (September to November) compared to the other three seasons. The mean litter size based on embryo/fetal counts was 4.6 (95% CI = 4.0-5.3; n = 40) and based upon placental site counts was 4.4 (95% CI = 3.9-4.8; n = 105). Prevalence of fetal resorption was 32.6% (95% CI = 20.5-47.5; n = 43) with a mean of 2.8 resorptions per litter in those with at least one resorption (95% CI = 1.8-3.8; n = 14). This was the first study to estimate previous litter size of non-pregnant, free-ranging dogs based upon placental sites. Litter size data from this study will be used in a population demographic model to predict the long-term impact of animal birth control (ABC) on the free-ranging dog population in Jodhpur. Increasing the efforts to surgically sterilize bitches prior to the time of year of peak pregnancy or whelping will help maximize the impact of an ABC program on the Jodhpur free-ranging dog population.

Analysis of trends in the full publication of papers from conference abstracts involving pre-harvest or abattoir-level interventions against foodborne pathogens.

Study results are often presented as abstracts at scientific conferences before publication as full articles in peer-reviewed journals. Given the current emphasis on evidence-based decision-making, it is vital that the peer-reviewed literature represents as broad and un-biased a selection of studies as possible. While the proportion of abstracts published as full papers in the peer-reviewed literature has been extensively studied in human healthcare, no such studies have been published in the field of food safety. The goal of this study was to estimate the proportion published and average time to publication for conference abstracts involving studies of pre-harvest or abattoir interventions to reduce foodborne pathogens. Abstracts were obtained by hand-searching available proceedings between 1995 and 2004 from 10 conferences. Included abstracts were limited to those detailing non-observational, controlled in vivo trials where outcome(s) were measured in livestock, carcasses or eggs. Data on abstract type (500 words), species, intervention, study type, sample size, number housed together and outcomes were recorded. Four databases (Agricola, CAB, Web of Science, Scholar's Portal) were searched for published papers corresponding to the conference abstracts using author and intervention/pathogen terms. Time to publication and overall median time to publication were estimated. Chi-squared, logistic regression and survival analyses were used to test for significant differences in proportion published and time to publication between variable levels. Of the 149 abstracts identified, 68 (45.6%) were published in peer-reviewed journals within 4 years. The median time to publication was 13.5 months (range: 0, 72). Abstracts shorter than 1 page were significantly more likely to be published (OR=2.2, 95% CI=1.0, 4.8), and abstracts involving pork or pigs were significantly less likely to be published that those involving poultry (OR=0.4: 0.2, 0.8). Abstracts reporting at least one positive outcome were more likely to be published (OR=2.608: 1.097, 6.196) and were published faster (HR=2.3: 1.1, 4.7). Time to publication decreased with the number of positive outcomes reported (HR=1.1: 1.0, 1.3). Sample size could only be determined for 46% of abstracts, with a median sample size of 9 (range 1-378), and housing was sufficiently described to determine sample size in 35% of pre-slaughter studies. The potential effects of this bias on systematic reviews and uses of interventions could be significant, and thus improvements may be warranted in the proportion of conference abstracts resulting in papers in the peer-reviewed literature.

Contact rates of raccoons (Procyon lotor) at a communal feeding site in rural eastern Ontario.

Intra- and interspecific contact rates of 12 adult (five females, seven males) raccoons (Procyon lotor) were recorded while these animals fed at a rural garbage dump 40 km north of Kingston, Ontario, Canada from 15 June to 5 September 1995. While raccoons were being observed, they bit, and were bitten, by their conspecifics an average of 0.99 (+/- 0.21) and 1.28 (+/- 0.21) times per hour, respectively, while feeding. Based on mean nightly contact rates (which included time when raccoons were not observed), raccoons bit one of their conspecifics once every 3 nights while feeding. The mean rate of bites made and received per hour for males was not significantly different from lactating females. There was no detectable difference between the mean rate of bites made and received per hour for raccoons which regularly versus occasionally fed at the dump. No interspecific contacts were observed, though raccoons and striped skunks (Mephitis mephitis) often fed at the dump concurrently. The contact rates in this study are the first to be calculated for raccoons directly from field data and will be useful as a point of reference for modeling rabies spread in raccoons in areas with similar site characteristics.