The welfare of ill and injured feedlot cattle: a review of the literature and implications for managing feedlot hospital and chronic pens.

By definition, ill and injured animals are on the negative valence of animal welfare. For beef cattle kept in feedlot settings, advances in cattle health management have resulted in a greater understanding and prevention of illness and injury. However, the management of cattle once they become ill and injured is an understudied area, and there are gaps in knowledge that could inform evidence-based decision-making and strengthen welfare for this population. The aim of this review is to provide a comprehensive overview of the acquired knowledge regarding ill and injured feedlot cattle welfare, focusing on existing knowledge gaps and implications for hospital and chronic pen management and welfare assurance. Ill and injured feedlot cattle consist of acutely impaired animals with short-term health conditions that resolve with treatment and chronically impaired animals with long-term health conditions that may be difficult to treat. A literature search identified 110 articles that mentioned welfare and ill and injured feedlot cattle, but the population of interest in most of these articles was healthy cattle, not ill and injured cattle. Articles about managing ill and injured cattle in specialized hospital (n = 12) or chronic (n = 2) pens were even more sparse. Results from this literature search will be used to outline the understanding of acutely and chronically ill and injured feedlot cattle, including common dispositions and welfare considerations, behavior during convalescence, and strategies for identifying and managing ill and injured cattle. Finally, by working through specific ailments common in commercial feedlot environments, we illustrate how the Five Domains Model can be used to explore feelings and experiences and subsequent welfare state of individual ill or injured feedlot cattle. Using this approach and our knowledge of current industry practices, we identify relevant animal-based outcomes and critical research questions to strengthen knowledge in this area. A better understanding of this overlooked topic will inform future research and the development of evidence-based guidelines to help producers care for this vulnerable population.

Providing elevated structures in the pullet rearing environment affects behavior during initial acclimation to a layer aviary.

Spatial abilities of hens are particularly sensitive to development during early life. Experiences in pullet housing may have lasting consequences on adult hens' movements in cage-free environments. We tested whether opportunities to access elevated spaces during rearing improved hens' use of a multitiered aviary. Female Dekalb White pullets were reared in either floor pens (FL), single-tiered aviaries (ST), or 2-tiered aviaries (TT; n = 5 pens/environment) through 16 wk of age. Rearing structures were replaced with identical multitiered aviaries at 17 wk. The distribution of the flock within the aviary and the vertical transitions of 10 focal hens/pen across the aviary were determined from videos recorded during their first (D1) and seventh (D7) day of aviary access, as well as at 19, 23, and 27 wk of age. Prevalence of floor eggs was recorded weekly from 17 to 28 wk of age. On D1, more ST and TT hens utilized the aviary during the daytime (P = 0.0077), made more vertical transitions when searching for a roosting spot in the evening (P = 0.0021), and maintained a consistent distance traveled during transitions compared to FL hens (P = 0.02). These differences disappeared by D7, except that ST and TT hens continued to roost on the highest perches of the aviary more (P < 0.0001) than FL hens through 27 wk of age. FL hens laid more floor eggs than ST and TT hens for the first 2 wk of lay (P < 0.0001). The majority (97.9%) of vertical transitions was controlled. Uncontrolled transitions were highest at D1 and decreased by D7 (P = 0.0009) and were not affected by rearing (P = 0.33). The results suggest that hens reared with minimal height are hesitant to use the laying hen aviaries when they are first transferred. They acclimate within 1 to 2 wk, but continue to roost less in the highest accessible level.

Validation of Standing and Locomotion Scoring, Behavioral Assessments, and Mechanical Nociceptive Threshold Testing on Naturally Occurring Sow Lameness.

The objective of this study was to validate standing and locomotion lameness scoring, mechanical nociceptive threshold testing, and behavioral profile tools for the diagnosis of naturally occurring lameness etiologies in pigs. A total of 55 crossbred gilts and sows obtained from a commercial farm were enrolled in the study; with sound pigs classified as controls (8) and the remainder as lame due to integumentary (20), musculoskeletal (15), and combinations of integumentary and musculoskeletal (12) etiologies. Standing and locomotion lameness, mechanical nociceptive threshold (MNT) test, pig-human interventions, and latency to complete an obstacle course were evaluated. Standing and locomotion lameness scoring systems, MNT, and pig behavior (latency) were capable of discriminating between animals with mild organic lameness and animals that were sound and may have utility on the farm for staff to use to identify and manage lame animals. In rare instances, the tools used here were able to discriminate between broad categories of lameness etiology.

Evaluation of a Behavioral Test for Sickness Behavior Associated with Fusarium Mycotoxin Ingestion in Female Beagle Dogs (Canis familiaris).

Animals exhibit behavioral changes during illness, including lethargy, anorexia, fever, adipsia, and anhedonia, which are believed to comprise an adaptive evolutionary strategy. Exploratory and social behaviors generally decrease during illness, but behavioral changes of dogs during illness have not been described. The objective of this study was to evaluate a novel canine behavior test during subclinical illness induced by dietary Fusarium mycotoxin. Twelve mature female beagle dogs received 3 treatment diets: a control diet (control), a diet formulated with grains contaminated with Fusarium mycotoxin (toxin), and the toxin diet together with a toxin binding agent (binder). All dogs received each diets for 14 d in a Latin square design with a 7-d washout period between diet trials. The test consisted of individually releasing dogs into the center aisle of the housing room for 4 min per day, during which interactions with familiar dogs in adjacent kennels were recorded by an observer outside the room who was blind to treatment groups. Total interactions, orientation, and attempted physical contact with other dogs were less frequent during the toxin and binder diet treatments. Conversely, frequencies of physical proximity and olfactory contact with familiar dogs in adjacent kennels were not associated with diet. In conclusion, induction of subclinical gastrointestinal illness influenced aspects of social interactions in beagle dogs. A clinical assessment sheet integrating these findings was developed to aid in early identification of subclinical illness in research dogs based on behavior.

Tralesinidase Alfa Enzyme Replacement Therapy Prevents Disease Manifestations in a Canine Model of Mucopolysaccharidosis Type IIIB.

Mucopolysaccharidosis type IIIB (MPS IIIB; Sanfilippo syndrome B; OMIM #252920) is a lethal, pediatric, neuropathic, autosomal recessive, and lysosomal storage disease with no approved therapy. Patients are deficient in the activity of N-acetyl-alpha-glucosaminidase (NAGLU; EC 3.2.150), necessary for normal lysosomal degradation of the glycosaminoglycan heparan sulfate (HS). Tralesinidase alfa (TA), a fusion protein comprised of recombinant human NAGLU and a modified human insulin-like growth factor 2, is in development as an enzyme replacement therapy that is administered via intracerebroventricular (ICV) infusion, thus circumventing the blood brain barrier. Previous studies have confirmed ICV infusion results in widespread distribution of TA throughout the brains of mice and nonhuman primates. We assessed the long-term tolerability, pharmacology, and clinical efficacy of TA in a canine model of MPS IIIB over a 20-month study. Long-term administration of TA was well tolerated as compared with administration of vehicle. TA was widely distributed across brain regions, which was confirmed in a follow-up 8-week pharmacokinetic/pharmacodynamic study. MPS IIIB dogs treated for up to 20 months had near-normal levels of HS and nonreducing ends of HS in cerebrospinal fluid and central nervous system (CNS) tissues. TA-treated MPS IIIB dogs performed better on cognitive tests and had improved CNS pathology and decreased cerebellar volume loss relative to vehicle-treated MPS IIIB dogs. These findings demonstrate the ability of TA to prevent or limit the biochemical, pathologic, and cognitive manifestations of canine MPS IIIB disease, thus providing support of its potential long-term tolerability and efficacy in MPS IIIB subjects. SIGNIFICANCE STATEMENT: This work illustrates the efficacy and tolerability of tralesinidase alfa as a potential therapeutic for patients with mucopolysaccharidosis type IIIB (MPS IIIB) by documenting that administration to the central nervous system of MPS IIIB dogs prevents the accumulation of disease-associated glycosaminoglycans in lysosomes, hepatomegaly, cerebellar atrophy, and cognitive decline.

The Use of Attractants to Stimulate Neonatal Piglet Interest in Rope Enrichment.

In the United States swine industry, preweaning mortality represents the highest mortality rate of any production phase, nearly half attributed to crushing. The overarching aim of this study was to determine if enrichment ropes would entice neonatal piglets away from the sow and reduce preweaning mortality. Rope enrichments were provided to 161 piglets from 26 sows after farrowing. Ropes were dipped in sunflower oil (n = 7), semiochemical (n = 8), or milky cheese (n = 11). Piglet purposeful rope investigations, weight gain, and mortality were recorded. On Day 2, 75% of piglets touched the enrichment at least once, and frequency ranged from 1 to 21 investigations across all treatments. Frequency (p = 0.20) and duration (p = 0.21) of investigations were not affected by treatment. Preweaning litter average weight gain did not differ between treatments (p = 0.71). MC (milky cheese) piglets had the lowest percent mortality when the enrichment ropes were present (Days 2 to 5, p = 0.01), and SC (semiochemical) piglets had the lowest percent mortality after the enrichment ropes were removed (Days 6 to weaning, p < 0.0001). This proof-of-concept study highlights the potential value of neonatal piglet environmental enrichment.

Outcomes of an Equine Assisted Learning Curriculum to Support Well-Being of Medical Students and Residents.

Objectives of this study were to evaluate an equine assisted learning (EAL) curriculum designed for medical students and resident physicians, and to determine impacts of the curriculum on participant perceptions of burnout and well-being. The EAL curriculum incorporated evidence-based skills and concepts to increase happiness and/or resilience. A pre/post intervention design was used, with 18 EAL participants receiving the curriculum within their month-long community based primary care clerkship elective, and 10 control (CTL) participants who did not receive the curriculum within their clerkship elective. Three waves of surveys tested participant responses before, immediately after, and 3 months after the intervention. Patient Health Questionnaire-4 (PHQ-4) screened for depression and anxiety, and Maslach Burnout Inventory- Human Services Survey for Medical Personnel (MBI) addressed burnout. Analysis of covariance evaluated differences between EAL and CTL groups. EAL participants rated the curriculum highly (9.2 on a 10-point scale). The evaluations were overwhelmingly positive with participants able to identify key concepts that were most helpful, how they would apply those concepts to patient care and interactions with colleagues, and how the horses added value to their learning experience. Significant positive effects of EAL on burnout were identified in terms of improved MBI personal achievement scores, as well as a trend towards improved well-being scores. There was also a trend (P < .08) towards PHQ-4 depression scores to be lower in EAL group at T3. In conclusion, this study is the first to provide AU: quantitative evidence of positive outcomes associated with an EAL curriculum designed to strengthen well-being in medical students and resident physicians.

Effects of Waiting Room and Feline Facial Pheromone Experience on Blood Pressure in Cats.

Obtaining accurate blood pressure measurements in cats is challenging due to the stressful nature of clinic visits. The objective of this study was to evaluate the effects of veterinary clinic waiting experiences and a feline pheromone spray on blood pressure in the cat. We hypothesized that reduced stress associated with bypassing the waiting room and use of synthetic feline facial pheromone (FFP) spray would result in lower blood pressure. A 2 × 2 factorial design involved two rooms and two FFP treatments. Thirty-nine healthy adult cats were recruited and were systematically assigned to four treatment combinations administered over four visits in 2016 and 2017. Cats were kept in the hospital waiting room or were taken directly to the exam room, with or without FFP treatment. All cats were then acclimated to the exam room for an additional 10 min, where vocalizations were recorded manually, before blood pressure measurements were collected using Doppler ultrasonography. Data were analyzed using generalized linear mixed models, with room × FFP interaction, visit, sex, and trial year in the model. There was no significant effect of waiting room by FFP interaction on blood pressure (n = 0.95). Mean blood pressure was significantly higher at visit 1 than visits 2 and 4 (P < 0.01), but higher at visit 3 than visit 2 (n = 0.02). Mean blood pressure was higher in males (n = 0.01), and males were more likely to be categorized as borderline hypertensive/hypertensive or severely hypertensive (n = 0.01). Number of vocalizations was significantly associated with waiting room by FFP interactions (P < 0.01), with fewer vocalizations associated with bypassing the waiting room and when FFP was provided. In conclusion, although we found some behavioral evidence supporting stress reduction when feline patients bypass the waiting room and are provided with FFP, these interventions did not result in lower blood pressure in a clinical setting.

Characterization of Efficacy and Animal Safety across Four Caprine Disbudding Methodologies.

There is a strong industry demand for technically simple and highly efficacious alternatives to heat cautery disbudding in goat kids that can be performed as a stand-alone procedure without adjunct anesthesia, and that result in improved overall welfare through reduced acute pain, reduced tissues healing interval, and a consistent safety record. The objective of this study was to consider the net effect of disbudding techniques on goat welfare by examining vocalization frequency, long-term efficacy and animal safety associated with four alternative caprine disbudding methods against sham-disbudded and heat-cautery controls. Sixty-five commercial male dairy kids were disbudded at 3-10 days of age with one of six disbudding treatments (clove oil injection, caustic paste, two cryosurgical methods, heat-cautery, and sham procedure). Heat cautery was 91% effective, caustic paste was 55% effective, and the other treatments were ineffective. Heat cautery and sham procedures resulted in similar vocalization efforts; freezing with a liquid-nitrogen cooled iron resulted in significantly greater vocalization numbers. No unintended paste transfer injuries were observed with short-term application of the caustic paste. Heat cautery resulted in numerous superficial infections but no permanent injury. Clove oil injection was associated with several unexpected and severe complications including unintended tissue necrosis, temporary paresis, skull defects, meningitis, and death. Collectively, we did not find that any of the alternative methods of disbudding provided a feasible option over heat cautery to improve welfare.

Innovative strategies for managing swine welfare during the COVID-19 pandemic in Iowa.

Coronavirus Disease 2019 (COVID-19) was declared a global pandemic on March 11, 2020 by the World Health Organization and its impact on animal agriculture in the United States was undeniable. By April, COVID-19 resulted in the simultaneous closure or reduced operations of many meat processing plants in the upper Midwest, leading to supply chain disruptions. In Iowa, the leading pork production and processing state, these disruptions caused producer uncertainty, confusion, and stress, including time-sensitive challenges for maintaining animal care. The Iowa Resource Coordination Center (IRCC) was quickly created and launched by the Iowa Department of Agriculture and Land Stewardship (IDALS). The IRCC included public representation from the Iowa Pork Producers Association (IPPA), Iowa Pork Industry Center (IPIC), and Iowa State University Extension and Outreach, and private partners including producers, veterinarians, and technical specialists. Supporting swine welfare, the IRCC provided information on management strategies, dietary alterations to slow pig growth, alternative markets, on-farm euthanasia, and mass depopulation under veterinary oversight. In a crisis, Iowa created a model that reacted to producers' pragmatic, mental and emotional needs. This model could be quickly replicated with an introduction of foreign animal disease.

Effects of litter floor access and inclusion of experienced hens in aviary housing on floor eggs, litter condition, air quality, and hen welfare.

With different cage-free (CF) housing styles and management schemes, retailers have developed their own CF criteria. One highly debated aspect is if hens may be kept inside the system for part of the day-during the first few hours after lights-on. Research is lacking regarding the impacts of such a practice on hen welfare, incidence of eggs laid on the litter floor, litter condition, and air quality. This 14-mo field study was conducted to help assess such impacts. Hens (Dekalb White) in an aviary house (50,000-hen nominal capacity) were allowed to have full litter access (FLA) vs. part-time litter access (PLA) from 10:50 am to 9:00 pm, coupled with the absence or presence of experienced hens (1.5% of the population), hence a 2 × 2 factorial arrangement. The measured variables included a) incidence of floor eggs, b) percentage of birds remaining on litter floor at night, c) mortality, d) body weight (BW) and BW uniformity, e) litter condition (depth, moisture content, texture, amount removed, and bacteria concentration), f) environmental conditions, and g) welfare conditions (10 variables). Compared to FLA, PLA had a significantly lower incidence of floor eggs (1.4 ± 0.1 vs. 12.6 ± 1.1 eggs per hen housed as of 76 weeks of age (WOA), i.e., approximately 89% reduction), less manure deposition on the floor (0.53 ± 0.02 vs. 1.05 ± 0.04 kg/100 hens/d, dry basis, i.e., approximately 50% reduction), and lower ammonia concentrations due to drier litter (averaging 22% lower). Inclusion of 1.5% experienced hens in the young flock did not show benefit of reducing the incidence of floor eggs (P = 0.48). The percentage of hens remaining on the floor at night was low (< 0.01%) in all cases from 24 WOA onward. No differences were detected between FLA and PLA in hen welfare conditions, mortality, BW, BW uniformity, bacteria concentration in the litter, air temperature, or relative humidity.

Incidence, Severity, and Welfare Implications of Lesions Observed Postmortem in Laying Hens from Commercial Noncage Farms in California and Iowa.

The egg industry is moving away from the use of conventional cages to enriched cage and noncage laying hen housing systems because of animal welfare concerns. In this study, the prevalence and severity of lesions in noncage laying hens from commercial farms in two of the largest egg-producing states, California and Iowa, were evaluated by postmortem examination. Hens that died or were culled were collected during early, mid, and late stages of the laying cycle from 16 houses on three farms. Of the 25 gross lesions identified for study, 22 were observed, with an average of four lesions per hen. Vent cannibalism, reduced feather cover, keel bone deformation, and beak abnormalities were the most frequent lesions, observed in ≥40% of hens. Other common lesions were cloacal prolapse (30.5%), footpad dermatitis (24.3%), and septicemia (23.1%). Beak abnormality and enteric disease had the highest proportion of severe lesions. Pearson chi-square analysis revealed a number of stage-of-lay effects (P ≤ 0.05), some of which differed by state. For both states combined, the lesions observed more frequently during early lay were beak abnormalities, northern fowl mite infestation, and cage layer fatigue, whereas during mid lay, they were poor feather cover, vent cannibalism, footpad dermatitis, keel bone deformation, respiratory disease and roundworms. Feather pecking and cloacal prolapse were most common during late lay. Although differences in hen genetics, farm management practices, and environmental factors could all have affected the results of this study, the information provides a better understanding of hen health in noncage housing systems and could help to identify potential interventions to reduce hen welfare problems.

An Observational Study of the Effects of Therapeutic Hoof Blocks on the Locomotion, Behavior, and Production of Healthy Dairy Cattle.

Therapeutic hoof blocks have been recommended for treatment of sole ulcers in dairy cattle; however, they are underutilized in the industry. Twenty Holstein cows were randomly assigned to receive a wooden hoof block applied to the left hind leg (n = 5), to the right hind leg (n = 5), or no hoof blocks (n = 10). Accelerometers were affixed to both hind legs of 10 blocked cows and 5 control cows. Cows were observed for locomotion scores, and milk production was recorded. Mixed models were constructed to determine effects of block application on behavior, milk production, and locomotion. Activity was altered by day, with cows being most active on Day - 1. The mean number of daily lying bouts and lying bout duration did not differ by treatment. Locomotion scores were higher for blocked cows on Days 1, 2, and 3 compared with baseline; however, milk production did not differ between treatments. In conclusion, although block application affected the appearance of locomotion, it did not appear to adversely affect the behavior or milk production of sound dairy cows.

Pain and sickness behavior associated with corneal lesions in dairy calves.

Infectious bovine keratoconjunctivitis (IBK) is a common corneal disease of calves that adversely affects animal welfare by causing pain and weight loss. Identifying behavioral indicators of pain and sickness in calves with IBK is necessary for designing studies that aim to identify effective means of pain mitigation. Consistent with principles of the 3Rs for animal use in research, data from a randomized blinded challenge study was used to identify and describe variation of behaviors that could serve as reliable indicators of pain and sickness in calves with corneal injuries. Behavioral observations were collected from 29 Holstein calves 8 to 12 weeks of age randomly allocated to one of three treatments: (1) corneal scarification only, (2) corneal scarification with inoculation with Moraxella bovoculi and (3) corneal scarification with inoculation with Moraxella bovis. Behavior was continuously observed between time 1230 - 1730 h on day -1 (baseline time period) and day 0 (scarification time period). Corneal scarification and inoculation occurred between 0800 - 1000 h on day 0. Frequency of head-directed behaviors (head shaking, head rubbing, head scratching) and durations of head rubbing, feeding, standing with head lifted, lying with head lifted and sleeping were compared between study days and groups. Following scarification, the frequency of head-directed behavior significantly increased (p = 0.0001), as did duration of head rubbing (p=0.02). There was no significant effect of trial, trial day, treatment or treatment-day interaction on other behaviors studied. Our study demonstrated that head-directed behavior, such as head shaking, rubbing and scratching, was associated with scarification of eyes using an IBK challenge model, but sickness behavior was not observed.

Pharmacokinetics of flunixin meglumine in mature swine after intravenous, intramuscular and oral administration.

BACKGROUND: The purpose of this study was to determine intravenous (IV), intramuscular (IM) and oral (PO) FM PK in mature swine. Appropriate pain management for lameness in swine is a critical control point for veterinarians and producers, but science-based guidance on optimal housing, management and treatment of lameness is deficient. Six mature swine (121-168 kg) were administered an IV, IM, or PO dose of flunixin meglumine at a target dose of 2.2 mg/kg in a cross-over design with a 10 day washout period between treatments. Plasma samples collected up to 48 hours post-administration were analyzed by high pressure liquid chromatography and mass spectrometry (HPLC-MS) followed by non-compartmental pharmacokinetic analysis. RESULTS: No adverse effects were observed with flunixin meglumine administration for all routes. Flunixin meglumine was administered at an actual mean dose of 2.21 mg/kg (range: 2.05-2.48 mg/kg) IV, IM and PO. A mean peak plasma concentration (CMAX) for IM and PO administration was 3748 ng/ml (range: 2749-6004 ng/ml) and 946 ng/ml (range: 554-1593 ng/ml), respectively. TMAX was recorded at 1.00 hour (range: 0.50-2.00 hours) and 0.61 hours (range: 0.17-2.00 hours) after PO and IM administration. Half-life (T ½ λz) for IV, IM and PO administration was 6.29 hours (range: 4.84-8.34 hours), 7.49 hours (range: 5.55-12.98 hours) and 7.08 hours (range: 5.29-9.15 hours) respectively. In comparison, bioavailability (F) for PO administration was 22% (range: 11-44%) compared to IM F at 76% (range: 54-92%). CONCLUSIONS: The results of the present study suggest that FM oral administration is not the most effective administration route for mature swine when compared to IV and IM. Lower F and Cmax of PO-FM in comparison to IM-FM suggest that PO-FM is less likely to be an effective therapeutic administration route.

Behavioral responses of cattle to pain and implications for diagnosis, management, and animal welfare.

Pain is a subjective experience in humans and livestock and can only be measured indirectly, posing challenges for veterinary practitioners in terms of diagnosis and treatment of bovine pain. In this review, attitudes of citizens, producers, and veterinarians are explored regarding pain and its associations with animal welfare and husbandry procedures. Behavior used to quantify pain in cattle is identified in terms of pain-specific behaviors and general behavioral responses that can be observed during painful procedures or convalescence. Finally, nociception and cognitive tests used for reporting pain in human patients are investigated for application to bovine patients.

Reduction in pain response by combined use of local lidocaine anesthesia and systemic ketoprofen in dairy calves dehorned by heat cauterization.

This study assessed the efficacy of ketoprofen for mitigating pain following dehorning with an electric cautery iron. Forty Holstein heifer calves, 4 to 8 wk of age, were randomized to receive a lidocaine cornual nerve block and either an injection of ketoprofen (3 mg/kg IM) or physiological saline, 10 min prior to dehorning. Cortisol was measured from serum obtained 10 min prior to dehorning and at 3 and 6 h post-dehorning. Calf behavior was video-recorded between 0 to 2, 3 to 5, and 6 to 8 h post-dehorning, and frequency of ear flicks, head shakes, head rubs, lying, standing, feeding, and grooming were recorded. Finally, 24-h intake of calf starter was recorded. There was no effect of treatment on cortisol (P > 0.1); however, ketoprofen-treated calves displayed less ear-flicks and total head behavior (P < 0.05), and tended to consume more starter (P = 0.09) than control calves. Ketoprofen is effective for mitigating behavioral effects of postsurgical pain following dehorning in 4- to 8-week-old calves.

Transmission of foodborne zoonotic pathogens to riparian areas by grazing sheep.

The objective of this study was to determine if sheep grazing near riparian areas on pasture in Ontario are an important risk factor for the contamination of water with specific foodborne pathogens. Ten Ontario sheep farms were visited weekly for 12 wk during the summer of 2005. Samples of feces, soil, and water were collected and analyzed for the presence of Escherichia coli O157:H7, Salmonella spp., Campylobacter jejuni and C. coli, and Yersinia enterocolitica, by bacteriological identification and polymerase chain reaction (PCR). The data was analyzed as repeated measures over time using mixed models. No samples were positive for Salmonella, and no samples were confirmed positive for E. coli O157:H7 after PCR. Levels of Campylobacter were highest in the soil, but did not differ between soil where sheep grazed or camped and roadside soil that had never been grazed (P = 0.85). Levels of Yersinia were highest in water samples and were higher in soil where sheep had access (P = 0.01). The prevalence of positive Campylobacter and Yersinia samples were not associated with locations where sheep spent more time (Campylobacter P = 0.46, Yersinia P = 0.99). There was no effect of stocking density on the prevalence of Campylobacter (P = 0.30), but as the stocking density increased the levels of Yersinia increased (P = 0.04). It was concluded that although sheep transmit Yersinia to their environment, pastured sheep flocks are not major risk factors for the transmission of zoonotic pathogens into water.