The challenges of pig farming in Hong Kong: a study of farmers' perceptions and attitudes towards a pig health and production management service.

BACKGROUND: Pig farming in Hong Kong differs markedly from other places in the world, with a highly urbanised population, the majority of pigs being imported for slaughter, and limited on-farm veterinary support. Little is known about the barriers and attitudes of pig farmers in Hong Kong and their expectations of a new pig health and production management service provided by veterinarians. We collected qualitative and quantitative data to 1) describe pig farms, 2) identify barriers to pig farming in Hong Kong and 3) describe the perceptions of the new service. Thematic analysis was conducted to identify barriers and attitudes. RESULTS: Eight and nine out of 38 pig farmers agreed to participate in the qualitative and quantitative components, respectively. All farms were farrow-to-finish farms with a median of 2800 (range 950 to 7000) pigs per farm. Three themes were identified during the interview analysis and could be ranked based on their importance to the farmers: the regulatory environment (Theme 1), veterinary support structures (Theme 2), and the sustainability of the pig industry (Theme 3). Farmers expressed dissatisfaction with the regulation of the industry and veterinary services on offer within Hong Kong. However, farmers did note that the provision of a new pig health and production management service was as a positive development. The public perception of pig farming, market forces, and competition from mainland pig farmers have resulted in sustainability challenges for the industry. CONCLUSIONS: Farmers identified very specific local systems and challenges unique to pig farming in Hong Kong. The lack of veterinary support was one of these challenges and although a certain level of scepticism towards the new pig health and production service was expressed, farmers indicated their interest and listed areas where they would benefit from improved veterinary support. Prior experiences of veterinary services clouded farmers perceptions of the usefulness of a new service. To be successful in this environment, clear communication about the goals, role and limitations of the new on farm service is crucial, as is the alignment with the needs of farmers. Despite the small sample size, the qualitative methodology used allows us to assume that these themes give a general idea of what Hong Kong farmers' concerns and attitudes are.

Preliminary insight into horse owners' perceptions of, and attitudes towards, exotic diseases in the United Kingdom.

BACKGROUND: The potential for an exotic disease incursion is a significant concern for the United Kingdom (UK) equine industry. Horse owners' perceptions of, and attitudes towards, exotic diseases can influence decisions to adopt disease preparedness strategies. The objectives of this study were to describe horse owners' 1) perceptions of the term 'exotic disease', and 2) attitudes towards their risk of being affected by an exotic disease. In order to address these objectives, qualitative content analysis was undertaken on data collected using two open-ended survey questions. RESULTS: Horse owners (n = 423) perceived exotic diseases as 1) belonging somewhere else, and 2) a dangerous threat to their horse(s). The term 'exotic' was associated with being foreign, non-native, and out-of-place in the UK. Attitudes towards exotic disease risk were summarised into four categories: 1) responsible horse owners prevent disease, 2) horse owners need support to stop disease spread, 3) risk depends on proximity to the 'risky' horse, and 4) some risk is inevitable. A 'responsible' owner was aware of health hazards and took actions to protect their horse from disease. Reliance on others, including stakeholders, to uphold disease prevention in the community led to feeling vulnerable to disease threats. When evaluating risk, horse owners considered which horses were the 'riskiest' to their horse's health (horses that travelled, participated in competitions, or were simply unfamiliar) and avoided situations where they could interact. Despite undertaking disease prevention measures, the perceived uncontrollable nature of exotic diseases led some owners to feel an incursion was inevitable. CONCLUSIONS: Without accounting for horse owners' perceptions of, and attitudes towards, exotic diseases, recommendations to increase preparedness may be ineffective. Improved communication among stakeholders in the industry may assist in clarifying expectations for exotic disease-specific prevention measures. A collaborative approach among horse owners and stakeholders is recommended to improve disease preparedness within the industry.

Comparison of Metzenbaum scissors and Y-shaped fasciotome for deep metatarsal fasciotomy for the treatment of proximal suspensory ligament desmopathy in horses.

OBJECTIVE: To quantitate the iatrogenic injury associated with deep plantar metatarsal fasciotomy performed with Metzenbaum scissors compared with a Y-shaped fasciotome. STUDY DESIGN: Experimental ex vivo surgical study. STUDY POPULATION: Cadaveric hind limbs (n = 20) from 10 sound thoroughbred racehorses. METHODS: A plantar metatarsal fasciotomy was performed, extending from the proximal extent of the deep metatarsal fascia, distally. Hind limbs were randomly assigned to 2 groups, undergoing fasciotomy with straight Metzenbaum scissors (n = 10) or a Y-shaped fasciotome (n = 10). Magnetic resonance imaging was performed before and after surgery to identify the maximal depth of any iatrogenic trauma. Gross examination of the surgical site included measuring the length of the incision in the deep metatarsal fascia and localizing iatrogenic trauma sustained by the plantar aspect of the proximal suspensory ligament (PSL) during the procedure. RESULTS: Iatrogenic injury to the PSL was identified in 6 of 10 and 9 of 10 specimens prepared with the fasciotome and Metzenbaum scissors, respectively (P = .03), and was most commonly located in the distal third of the fascial incision. Differences between the length of incision (P = .02) and the maximal depth of signal (P = .03) for incisions created with Metzenbaum scissors or a fasciotome were identified. CONCLUSION: The use of a fasciotome resulted in longer fascial incisions and less severe iatrogenic trauma to the PSL compared with using Metzenbaum scissors. CLINICAL SIGNIFICANCE: A Y-shaped fasciotome may be the preferred surgical instrument for successful desmopathy of the PSL fasciotomy because a greater release of compartmental pressure is possible through a longer incision with minimal iatrogenic trauma to the underlying PSL.

Bursting strength of surgeon's and self-locking knots for closure of ventral midline celiotomy in horses.

OBJECTIVE: To compare the bursting strength and failure mode of ventral midline celiotomy closed with a simple continuous suture pattern with 1 of 2 knot combinations, a novel self-locking knot combination of a forwarder start with an Aberdeen end knot (F-A) and a traditional combination of a surgeon's start with a surgeon's end knot (S-S). STUDY DESIGN: Ex vivo experimental. SAMPLE POPULATION: Equine cadavers (n = 14). METHODS: A 20-cm ventral midline celiotomy was created in 14 equine cadavers. Horses were assigned to celiotomy closure with an F-A or S-S knot combination. Prior to closure, a 200-L inflatable bladder was placed in the abdomen and then insufflated until failure of the celiotomy closure. The horses' signalment, weight, breed, and age, as well as knot combination type, mode of failure, closure time, and bursting strength (mm Hg) were recorded. RESULTS: The median bursting strength was significantly greater when incisions were closed with the F-A knot combination (388 mm Hg) compared with the S-S knot combination (290 mm Hg) (P = .035). Most incisions failed along the fascia when closed with F-A combinations and at the knot when closed with S-S combinations. CONCLUSION: The bursting strength of ventral midline incisions in equine cadavers was increased by an average of 25% when closed with the self-locking F-A knot combination. CLINICAL SIGNIFICANCE: Closing ventral midline celiotomies with an F-A knot combination may provide a more secure closure than the traditional S-S knot combination. Additional in vivo investigation is required prior to recommending this closure in clinical cases.

Identification of Targeting Peptides for Mucosal Delivery in Sheep and Mice.

In this study we identified and characterized a novel cyclic peptide that facilitates the rapid transportation of conjugated molecules across the epithelial layer of the small intestine. The peptide was initially selected from phage display libraries using a large animal experimental model, which employed consecutive in vitro and in vivo panning. The procedure was designed to enrich for peptides that facilitated transcytosis across the intestinal epithelium into the intestinal afferent lymphatic system. A small set of peptides was repeatedly isolated using this selection method; however, the cyclic nonamer CTANSSAQC, 13C, dominated. The activity of the putative targeting peptide 13C was then verified using a mouse model. These experiments showed that the 13C peptide as well as macromolecules conjugated to it were rapidly transported across the intestinal mucosa into distinct subsets of epithelial cells and CD11c+ cells located in the lamina propria and Peyer's Patches. Significant amounts of intact protein could be delivered into the systemic circulation after rectal and nasal application. Thus, peptide 13C is regarded as an attractive carrier candidate for mucosal delivery of large molecules. The preferential targeting to distinct intestinal cells may be utilized to deliver active biological drugs for the effective control of diseases of the gut.

The prognosis for return to athletic function for Thoroughbred racehorses in Hong Kong with injuries to the palmaroproximal aspect of the metacarpus diagnosed using low-field magnetic resonance imaging.

OBJECTIVE: To evaluate and compare the prognosis for Thoroughbred racehorses to return to galloping and racing with injuries to the palmaroproximal metacarpus diagnosed with MRI. ANIMALS: 29 flat racing Thoroughbreds at the Hong Kong Jockey Club that underwent MRI between 2014 and 2022. METHODS: Clinical, radiographic, ultrasonographic, and MRI reports were collected from veterinary clinical records, and these were combined with training and racing data. Horses were categorized on the basis of MRI diagnosis: (1) proximal suspensory ligament (PSL) involvement only, (2) PSL and concurrent proximal third metacarpal (MC3) bone involvement, and (3) proximal MC3 bone involvement only. The following were compared for prognosis for return to athletic function: return to galloping or racing, and reinjury. RESULTS: Overall, the prognosis for return to athletic function was fair, with 92% (22/24; P = .53) and 67% (16/24; P = .73) of horses returning to galloping and racing, respectively. There was a relatively low reinjury rate, with 18% (4/22) of horses reinjuring. Horses with concurrent injury to both the PSL and proximal MC3 bone (Category 2) took longer to return to gallop (median, 116; IQR, 100.5 to 160), when compared with horses having only PSL injury (median, 69; IQR, 43 to 80; P = .04). Of the 4 horses that reinjured, 3 (75%) were horses in Category 2. CLINICAL RELEVANCE: The findings from this study suggest that injuries involving both PSL and proximal MC3 bone concurrently require a longer rehabilitation period than those with PSL involvement alone.

'I want to be the sort of owner that he wants me to be': Rationales for biosecurity implementation among British horse owners.

BACKGROUND: Horse owners play a critical role in mitigating the risk of pathogen spread between horses. However, little is known about how they view biosecurity and whether they experience barriers to the uptake of preventive measures. OBJECTIVES: To explore horse owners' attitudes, perceptions, and experiences of biosecurity and identify how these factors shape horse owners' decisions for biosecurity implementation. STUDY DESIGN: Qualitative study using semi-structured interviews. METHODS: Interviews were conducted with 23 horse owners across Great Britain. Participants were purposively selected to include those in different geographic regions, with different management arrangements, and varied length of horse ownership experience. Interviews were audio-recorded, transcribed verbatim, and analysed using a critical realist thematic analysis. RESULTS: Participants felt a moral obligation to prioritise their horse's happiness, which became a challenge when certain biosecurity measures (e.g., quarantine) were perceived as compromising their horse's happiness or comfort (Theme 1). A lack of biosecurity was the social norm among shared yards and competition venues (Theme 2), which made it difficult for participants to implement biosecurity measures effectively on their own. Combined with the sense of moral obligation participants felt towards their horse, this meant that participants had to 'care double' (i.e., be more vigilant than they would otherwise) to compensate for collective inaction (Theme 3). MAIN LIMITATIONS: Participants may have been more interested in and/or knowledgeable about biosecurity than the general horse owning population. CONCLUSIONS: The findings highlight several challenges that could be addressed to improve biosecurity implementation among horse owners. Efforts to encourage improved uptake of biosecurity measures should focus on communicating how reducing the risk of disease aligns with horse care. Further research on social norms in the horse industry is needed, in addition to identifying strategies to encourage a collective adoption of biosecurity measures.

The impact of heat treatment of bovine milk on gastric emptying and nutrient appearance in peripheral circulation in healthy females: a randomized controlled trial comparing pasteurized and ultra-high temperature milk.

BACKGROUND: Heat treatments of dairy, including pasteurization and ultra-high temperature (UHT) processing, alter milk macromolecular structures, and ultimately affect digestion. In vitro, animal, and human studies show faster nutrient release or circulating appearance after consuming UHT milk (UHT-M) compared with pasteurized milk (PAST-M), with a faster gastric emptying (GE) rate proposed as a possible mechanism. OBJECTIVES: To investigate the impact of milk heat treatment on GE as a mechanism of faster nutrient appearance in blood. We hypothesized that GE and circulating nutrient delivery following consumption would be faster for UHT-M than PAST-M. METHODS: In this double-blind randomized controlled cross-over trial, healthy female (n = 20; 27.3 ± 1.4 y, mean ± SD) habitual dairy consumers, consumed 500 mL of either homogenized bovine UHT-M or PAST-M (1340 compared with 1320 kJ). Gastric content volume (GCV) emptying half-time (T50) was assessed over 3 h by magnetic resonance imaging subjective digestive symptoms, plasma amino acid, lipid and B vitamin concentrations, and gastric myoelectrical activity were measured over 5 h. RESULTS: Although GCV T50 did not differ (102 ± 7 min compared with 89 ± 8 min, mean ± SEM, UHT-M and PAST-M, respectively; P = 0.051), GCV time to emptying 25% of the volume was 31% longer following UHT-M compared with PAST-M (42 ± 2 compared with 32 ± 4 min, P = 0.004). Although GCV remained larger for a longer duration following UHT-M (treatment × time interaction, P = 0.002), plasma essential amino acid AUC was greater following UHT-M than PAST-M (55,324 ± 3809 compared with 36,598 ± 5673 µmol·min·L-1, P = 0.006). Heat treatment did not impact gastric myoelectrical activity, plasma appetite hormone markers or subjective appetite scores. CONCLUSIONS: Contrary to expectations, GE was slower with UHT-M, yet, as anticipated, aminoacidemia was greater. The larger GCV following UHT-M suggests that gastric volume may poorly predict circulating nutrient appearance from complex food matrices. Dairy heat treatment may be an effective tool to modify nutrient release by impacting digestion kinetics. CLINICAL TRIAL REGISTRY: www.anzctr.org.au (ACTRN12620000172909).

Hoof morphometry in a population of lame and nonlame working donkeys in Pakistan.

BACKGROUND: Hoof morphometry, conformation and shoeing practices have all been associated with lameness in horses. Hoof morphometry in working donkeys in Pakistan has not been objectively measured. OBJECTIVES: To quantitatively assess hoof morphology in donkeys, to identify factors underlying hoof morphology, and interrelationships between conformation, lameness, and shoeing status. STUDY DESIGN: Cross-sectional study. METHODS: Donkeys were assessed in-harness using a modified five-point lameness scale by two veterinarians and digital photographs of front hooves taken alongside a grid. Factor analysis was used to examine the interrelationships among morphometric data. Associations between conformation, shoeing, age and lameness were assessed. RESULTS: Sixty-one donkeys were examined; 28 were unshod. There were significant left-right hoof asymmetries between heel height (0.27, SD 0.92 cm; p = 0.02), toe-heel angle (2.97°, SD 8.85°; p = 0.03) and medio-lateral symmetry (0.5, SD 1.75 cm; p = 0.05). Ten percent of donkeys (n = 6) were sound and 64% donkeys (n = 39) were consistently lame. Conformational defects were seen in 41% (n = 25) of donkeys. Eleven factors were extracted, accounting for 83% of the variance encountered in the original variables. Shoeing, and asymmetry between or within feet were not associated with lameness in donkeys; older donkeys were more likely to be lame (p = 0.02). MAIN LIMITATIONS: As a convenience sample of draught donkeys, most of which were lame, the study may not reflect nonpathological hoof morphology in working donkeys. There are no validated objective lameness measures for donkeys and donkeys were in harness when assessed. CONCLUSION: This study represents a snapshot of hoof morphology and lameness in a single population and under various limitations. Further work should use larger datasets and more homogenous samples to discriminate between 'normal' and 'abnormal' feet and how these might contribute to lameness. Factor analysis highlighted the clustering of hoof morphometric features in donkeys, suggesting the potential for targeted studies in the future.

Recognition of emotion and pain by owners benefits the welfare of donkeys in a challenging working environment.

Working donkeys (Equus asinus) support human living standards globally. However, there is little information on the effect of human perceptions of emotion and pain on the welfare of working donkeys. We interviewed donkey owners (n = 332) in Pakistan to determine the relationship between human perspectives on donkey sentience: emotions and the ability to feel pain, and the routine working practices that could impact donkey welfare. The majority of donkey owners used padding under the saddle (n = 211; 63.6%; 95% CI (58.3%-68.9%)) and provided access to food (n = 213; 64.2%; 95% CI (58.9%-69.3%)) and water (n = 195; 58.7%; 95% CI (53.4%-64.1%)) during the working day. Owners reported that at some point in their donkey's life, 65.3% (95% CI (60.2%-70.5%)) had load-associated injuries, of which 27.7% (n = 92; 95% CI (22.8%-32.5%)) were wounds, 20.5% (n = 68; 95% CI (16.1%-24.8%)) were lameness and 7.2% (n = 24; 95% CI 4.4%-10.0%) were back pain. In total, 81.3% (95% CI 77.1%-85.5%; n = 270) of owners believed that their donkeys felt pain, and 70.2% (95% CI (65.2%-75.1%; n = 233) of owners believed that their donkeys had emotions. Multiple correspondence analysis (MCA) was used to understand the relationship between owners' recognition of emotions and pain in donkeys and their working practices. The MCA factor map revealed two clusters, named positive and negative clusters. The positive cluster included owner's recognition of donkey pain and emotions, the availability of food and water, use of padding under the saddle, absence of injuries along with the willingness to follow loading guidelines. The negative cluster represented practices that did not benefit donkey welfare, such as using saddles without padding and a lack of food and water during work. The presence of injuries, owners not recognizing that donkeys feel pain and emotion along with an unwillingness to follow loading guidelines were also found in the negative cluster. We show that the owners who recognized sentience in their donkeys were more likely to use practices that are good for donkey welfare. The ability of owners to identify sentience in donkeys, along with their willingness to follow welfare guidelines, are important factors in improving the lives of working donkeys.

Challenges to exotic disease preparedness in Great Britain: The frontline veterinarian's perspective.

BACKGROUND: Exotic diseases pose a significant risk to horse health and welfare. Several stakeholder groups, including primary care veterinarians, share responsibility for maintaining freedom from pathogens that cause exotic diseases. However, little is known about the current state of exotic disease preparedness within the British horse industry. OBJECTIVES: The aim of this study was to explore equine veterinarians' experiences of, and attitudes towards, exotic disease preparedness in Great Britain. STUDY DESIGN: This is a qualitative interview-based study. METHODS: Semistructured interviews were conducted with 14 primary care equine veterinarians in Great Britain. Participants were purposively selected to include perspectives across varying levels of experience, clientele and location. All interviews were recorded, transcribed verbatim and analysed using thematic analysis. RESULTS: Three themes were developed: (a) the reactive generalist, relating to participants' self-concept of their role as primary care practitioners; (b) working within the bounds of influence, encompassing participants' perceived inability to influence their clients' knowledge and behaviours and (c) a fragmented horse industry, illustrating the wider culture in which participants worked, characterised by a lack of cohesion amongst its members. MAIN LIMITATIONS: Only veterinarians' perspectives have been captured, so viewpoints from other stakeholders, such as horse owners and government officials, should be used to triangulate these findings. CONCLUSIONS: The findings suggest that improvements are required before an optimal level of exotic disease preparedness can be achieved. Additional support provided to frontline veterinarians, such as skills-based training (ie, clinical reasoning and collaborative relationship building), accessible and trusted emergency support networks and clear expectations and responsibilities during an outbreak are recommended to optimise exotic disease preparedness.

Welfare Concerns for Mounted Load Carrying by Working Donkeys in Pakistan.

Working donkeys (Equus asinus) are vital to people's livelihoods. They are essential for carrying goods, however, globally, overloading is one of the primary welfare concerns for working donkeys. We studied mounted load carrying by donkeys and associated factors in Pakistan. A cross-sectional study of donkey owners (n = 332) was conducted, and interviews were undertaken based on a questionnaire. Owners estimated that the median weight of their donkeys was 110 kg [interquartile range (IQR) 100-120 kg], and that they carried a median mounted load of 81.5 kg (IQR 63-99 kg). We found that 87.4% of donkeys carried a load above 50% of their bodyweight ratio (BWR), the median BWR carried was 77.1% (IQR 54.5-90.7%), and 25.3% of donkeys carried above 90% BWR. Donkeys that were loaded at more than 50% BWR were more likely to adopt sternal recumbency compared to donkeys loaded with less weight (P = 0.01). Donkeys carrying construction material were more likely to carry more than the median BWR, when compared to domestic loads (P < 0.001). Younger donkeys aged between one and 5 years carried more than the median BWR compared to those aged over 15 years (P = 0.03). For the models with donkeys carrying median BWR and above 90% BWR, those working in peri-urban and urban areas were more likely to carry a greater BWR than donkeys working in rural areas (P < 0.001; P < 0.001, respectively). For donkeys carrying more than 90% BWR, mixed breed donkeys carried higher loads compared to other breeds of donkeys (P < 0.001). Overloading based on current recommendations (50% BWR) was common, with the majority (87.4%) of donkeys reported to carry more than the recommended 50% limit. This survey provides evidence of on-the-ground working practices and factors associated with mounted load carrying, which is critical for developing evidence-based recommendations for loading, in order to improve the welfare of working donkeys.

Cross-Sectional Questionnaire of Donkey Owners and Farriers Regarding Farriery Practices in the Faisalabad Region of Pakistan.

Quality farriery is essential to ensure donkey welfare, and many intervention programs in low-middle income countries (LMICs) train farriers, and educate owners, regarding the farriery needs of donkeys. It is essential for interventional programs to understand the perspectives of all stakeholders in donkey-owning communities. A cross-sectional questionnaire study was conducted in the Faisalabad region of Pakistan. Ten farriers and 55 donkey owners participated in the study. Farriers reported receiving no formal training for farriery, insufficient wages (PKR 65 or USD 0.36 per hoof) and the requirement to use traditional tools. Farriers reported an average shoeing time of 5 min per hoof and shoeing between three and 30 donkeys a day. Donkeys were mostly shod while they were harnessed to a cart. Six donkey-owning farriers reported shoeing their donkeys every 20 to 25 days. Owners reported varying shoeing intervals of 20 days to 90 days. Shoeing interval was also affected by seasonal and weather changes. Owners considered their relationship with farriers as the most important factor in choosing a farrier rather than cost. A majority (87%) of the owners reported lameness in their donkeys. The study provides important insights into the many challenges and opportunities in developing quality donkey farriery in the region.

Stress fracture of the palmar, distal cortex of the third metacarpal bone: A diagnostic challenge with a good prognosis.

BACKGROUND: Transverse stress fracture of the palmar cortex of the distal aspect of the third metacarpal bone (TSF PCD McIII) is poorly documented. OBJECTIVES: To describe the typical signalment of this injury, the common clinical and radiological signs and prognosis. STUDY DESIGN: A retrospective hospital-based case series with follow-up of racing records. METHODS: All cases of TSF PCD McIII diagnosed among racehorses in training at the Hong Kong Jockey Club between 2011 and 2019 were identified. Clinical records were reviewed and documented signs were recorded for each case. Findings from a predefined list of radiological features were listed. Descriptive statistics were used to describe the age and training profile of horses, the clinical and radiological findings and time to return to ridden exercise. RESULTS: Twenty-three cases (n = 23) were identified. The majority (57%) had recently started or returned to training from a break and 35% (n = 8) of cases had not yet undertaken timed gallops at the time of injury. Most cases (20/23; 87%) were lame; in nine (39%), lameness was severe. Localised swelling of superficial soft tissues was reported in 15/23 (65%) cases. Pain on palpation of the distal McIII was present in 15/23 (65%) cases and in response to fetlock flexion in 12/23 (52%). Diffuse, localised increase in radiopacity, disruption to the outline of the bone periosteal surface and outward displacement of the button of the splint bone were common radiological features in early cases (70%, 67% and 67% of all cases). Sixty-one per cent of cases (14/23) were initially misdiagnosed. Most horses (n = 18/23) resumed training and racing after a median of 83 and 246 days. MAIN LIMITATIONS: Clinical notes were not consistent between cases. Radiographs were taken at different times. CONCLUSIONS: Horses commencing training are at risk of TSF PCD McIII, which presents with confusing clinical signs and subtle radiological findings. The long-term outlook is favourable.

Active learning for an evidence-based veterinary medicine course during COVID-19.

Epidemiology is often a challenging course that is not well appreciated by many students learning veterinary medicine. The curriculum for this topic can sometimes be dry, difficult for students to contextualize, and heavy with statistics and mathematical concepts. We incorporated the concepts of epidemiology that are most important for practicing veterinarians and combined these with evidence-based veterinary medicine principles to create a practical course for second-year undergraduate veterinary students. We share the structure of our course and the different learning components, which also included incorporating graduate student mentors for journal clubs and an assignment that culminated in some students publishing their review findings. Anecdotal responses from students suggest they enjoyed the course and learned skills they felt would be useful in veterinary practice to help them make evidence-based clinical decisions.

Incidence, recurrence, and outcome of postrace atrial fibrillation in Thoroughbred horses.

BACKGROUND: Atrial fibrillation (AF) impacts performance and horse and jockey safety. Understanding the outcomes of AF identified postrace will better inform regulatory policy. HYPOTHESIS/OBJECTIVES: To investigate the outcomes after episodes of AF identified postrace and determine whether affected horses are at increased risk of additional episodes compared to the general racing population. ANIMALS: Total of 4684 Thoroughbred racehorses. METHODS: Race records for Thoroughbred horses racing in Hong Kong from 2007 to 2017 were reviewed. Horses that performed below expectation were examined by cardiac auscultation and ECG. Incidence and recurrence of AF were compared between horses with and without a history of AF and between horses with paroxysmal and persistent episodes using Fisher's exact test. RESULTS: There were 96 135 race starts during the study. Atrial fibrillation was identified in 4.9% of horses, with an overall incidence of 2.7 episodes per 1000 starts. The incidence of AF in horses after any previous episode (12.8 per 1000 starts) was higher than for horses with no previous episode (2.4 per 1000 starts; odds ratio [OR], 5.3; 95% confidence interval [CI], 3.8-7.6). Recurrence was seen in 64% of horses previously treated for persistent AF, which was higher than recurrence in horses with paroxysmal AF (23%; OR, 5.9; 95% CI, 1.6-21.2). Median duration between episodes was 343 days (range, 34-1065). CONCLUSIONS AND CLINICAL IMPORTANCE: Thoroughbreds are at increased risk of recurrent AF after both paroxysmal and persistent episodes, but the duration of time between episodes varies widely. These findings support a substantial burden of AF among individual Thoroughbred racehorses.

Development of simulation models for transmission of Salmonid Rickettsial Septicaemia between salt water fish farms in Chile.

This study aimed at estimating parameters representing between-farm transmission of Salmonid Rickettsial Septicaemia (SRS) in Chile, and developing and validating simulation models to predict weekly spread of SRS between farms in Los Lagos (Region 10), using InterSpread Plus. The model parameters were estimated by analyses of the historical SRS outbreak data. The models incorporated time and distance-dependent transmission kernels, representing the probabilities of waterborne spread of SRS between farms. Seven candidate transmission kernels were estimated, with varying maximum distance of between-farm SRS spread (15-60 km). Farms were categorized by size (small; medium; large) and species (Coho salmon; Atlantic salmon; rainbow trout). The time that it took a farm to recover from infection was parameterized to be shortest for small Coho farms (median: 7 weeks), followed by medium and large Coho farms (median: 25 weeks), Atlantic salmon farms (median: 42 weeks, any size) and rainbow trout farms (median: 43 weeks, any size). The relative infectiousness parameters of rainbow trout farms were 1.5-6.3 times that of Coho or Atlantic salmon, or those of large farms was 1.3-4.2 times that of small or medium farms. The models predicted SRS prevalence in Region 10 between 2013 and 2015 (79 weeks) with 76.5%-93.0% overall accuracy. The model with a transmission kernel of <20 km (P20) achieved a maximum overall accuracy (93.0%). Within each neighbourhood, the accuracy of P20 varied between 32.4% and 88.1%; 13/20 neighbourhoods had a reasonable temporal agreement between the simulated and actual dynamics of SRS (within 5th-95th percentiles), but 5/20 neighbourhoods underestimated and 2/20 overestimated the SRS spread. The model could be used for evaluation of semi-global control policies in Region 10, while addition of other factors such as seasonality, ocean currents, and movement of infected fish may improve the model performance at a finer scale.

Factors associated with survival and racing performance of 114 Thoroughbred foals with septic arthritis compared with maternal siblings (2009-2015).

BACKGROUND: There is little consensus on factors associated with survival in foals with septic arthritis and limited data on long-term racing performance of Thoroughbred foals treated for septic arthritis. A more thorough understanding of short- and long-term outcome is necessary to help inform owners, and subsequently guide treatment. OBJECTIVES: To investigate factors associated with survival, and to analyse racing performance of foals with septic arthritis compared with their maternal siblings. STUDY DESIGN: Retrospective cohort and a case-control study. METHODS: Veterinary clinical records of Thoroughbred foals ≤180 days old that underwent arthroscopic, cannulae or through-and-through needle lavage for the treatment of septic arthritis between 2009 and 2015 were reviewed. Data included signalment, and clinicopathological information. The dam's foaling records were reviewed and the lifetime racing records were obtained for affected foals and two of their maternal siblings. Logistic regression analysis was used to determine factors associated with survival to discharge or racing. Comparisons between treated foals and their maternal siblings were made. RESULTS: Ninety (78%) of 115 foals diagnosed with septic arthritis were discharged alive. Foals <26 days old at the time of admission were five times less likely (P = .003) and foals with concurrent multisystemic disease were six times less likely (P = .02) to be discharged alive. Sixty (67%) foals discharged alive started in ≥1 race, and there was no difference in the proportion of foals that started in a race or racing performance between foals treated for septic arthritis and their maternal siblings. MAIN LIMITATIONS: Retrospective study design, limited number of foals with multiple joint involvement and failure to accurately record duration of clinical signs. CONCLUSIONS: Foals treated for septic arthritis at the Scone Equine Hospital, New South Wales, Australia had a good prognosis for survival, and for this cohort, foals that survived to discharge had a similar ability to race as their maternal siblings.

The effect of stress fracture occurring within the first 12 months of training on subsequent race performance in Thoroughbreds in Hong Kong.

BACKGROUND: Racehorses are at an increased risk of stress fracture within the first 12 months of racing and when resuming training after a break. Research in these high-risk periods and on the effect of performance post-recovery is limited. OBJECTIVES: To describe the occurrence of stress fractures, diagnosed by nuclear scintigraphy (NS), in racehorses' first 12 months training in Hong Kong, and their impact on racing performance and career length. STUDY DESIGN: Retrospective 1:2 matched case-control study. METHODS: Clinical records of horses with NS-diagnosed stress fractures within 365 days of import between 2006 and 2018 were collated. Cases and controls were matched on import date. Univariable conditional logistic regression compared signallment, pre-fracture training and post-recovery racing performance between cases and matched controls. Shared Frailty Cox regression analysed time from import to fracture and total career length. RESULTS: Eighty-seven horses sustained a NS-diagnosed fracture within their first year in Hong Kong (incidence risk 1.7% [95% confidence interval (CI) 1.4%-2.1%; N = 5180]). The humerus (42.0%; 95% CI 31.8%-52.6%; n = 39) and tibia (28.0%; 95% CI 19.1%-38.2%; n = 26) were the most common stress fracture sites. Cases missed a median of 63 days (Interquartile range (IQR) 49-82) of training because of fracture. Within the 12 months following diagnosis, case horses had a median of four (IQR 2-4, P < .0001) fewer race starts and were down HK$ 206 188 (IQR HK$ 0-436 800, P = .007) in race earnings compared to controls. Career length did not significantly differ between cases and controls (median 2 years and 3 months; IQR 15.3-39.1 months; P = .2). MAIN LIMITATIONS: Only stress fractures diagnosed by NS were included, hence, the study is not representative of all stress fractures occurring in racehorses in Hong Kong. CONCLUSIONS: Racehorses sustaining a stress fracture within 1 year of entering Hong Kong lost significant time in training, earnings and race starts. However, overall career length was unaffected.

Sea lice exposure to non-lethal levels of emamectin benzoate after treatments: a potential risk factor for drug resistance.

The avermectin derivative emamectin benzoate (EMB) has been widely used by salmon industries around the world to control sea lice infestations. Resistance to this anti-parasitic drug is also commonly reported in these industries. The objective of this study was to quantify the number of sea lice potentially exposed to sub-lethal concentrations of EMB while fish clear the drug after treatments. We assessed juvenile sea lice abundance after 38 EMB treatments on six Atlantic salmon farms, in a small archipelago in British Colombia, Canada, between 2007 and 2018. We fitted a standard EMB pharmacokinetic curve to determine the time when fish treated with this product would have EMB tissue concentrations below the recommended target therapeutic level. During the study, we estimated that for each sea lice treatment there was, on average, an abundance of 0.12 juvenile sea lice per fish during the time period when the concentrations of EMB would have been lower than 60ppb, the recommended therapeutic treatment level for sea lice. The findings from this study on metaphylactic anti-parasitic treatments identify a potential driver for drug resistance in sea lice that should be further explored.