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Introduction: The social licence of the Australian thoroughbred (TB) industry relies on the general public's perception of how they manage the animal in their care. Method: This study examines the horse, race and activity records for the 37,704 horses racing and training in Australia from 1 August 2017 to 31 July 2018. Three‐quarters (75%, n = 28,184) of TBs started in one of the 180, 933 race starts that occurred during the 2017–2018 Australian racing season. Results: Horses participating in the 2017–2018 Australian racing season had a median age of 4 years, with geldings more likely to be aged 5 years and older. The majority of the TB racehorse population were geldings (51%, n = 19,210), with 44% (n = 16,617) females and only 5% (n = 1877) entire males. Horses aged 2 years were three times more likely to not start in a race in that year compared with older horses. At the end of the 2017–2018 racing season, 34% of the population had an inactive status recorded. Horses aged 2 years (median two starts) and 3 years (median five starts) had fewer starts than older horses (median seven starts). Eighty‐eight percent (n = 158,339) of race starts were over distances of 1700 metres or less. Race starts by horses aged 2 years (46%, 3264 of 7100) were more likely to have occurred at a metropolitan meeting compared with starts by older horses. Conclusion: This study provides a national overview of the racing and training activities and TBs participating in the 2017–2018 Australian racing season. [ABSTRACT FROM AUTHOR]

The largest Australian farm‐based outbreak of Q fever originated from a dairy goat herd. We surveyed commercial dairy goat farms across Australia by testing bulk tank milk (BTM) samples using a commercial indirect enzyme‐linked immunosorbent assay and two quantitative polymerase chain reactions (PCRs). Of the 66 commercial dairy goat herds on record, managers from 61 herds were contacted and 49 provided BTM samples. Five of the surveyed herds were positive on at least one of the diagnostic tests, thus herd‐level apparent prevalence was 10% (95% confidence interval [CI] 4 to 22). True prevalence was estimated to be 3% (95% credible interval: 0 to 18). Herd managers completed a questionnaire on herd management, biosecurity and hygiene practices and risk factors were investigated using multivariable logistic regression. Herds with >900 milking does (the upper quartile) were more likely to be Coxiella burnetii positive (odds ratio = 6.75; 95% CI 1.65 to 27.7) compared with farms with ≤900 milking does. The odds of BTM positivity increased by a factor of 2.53 (95% CI 1.51 to 4.22) for each order of magnitude increase in the number of goats per acre. C. burnetii was not detected in samples from the majority of the Australian dairy goat herds suggesting there is an opportunity to protect the industry and contain this disease with strengthened biosecurity practices. Intensification appeared associated with an increased risk of positivity. Further investigation is required to discriminate the practices associated with an increased risk of introduction to disease‐free herds, from practices associated with maintenance of C. burnetii infection in infected dairy goat herds. [ABSTRACT FROM AUTHOR]

The number of horses leaving the Australian Thoroughbred (TB) racing industry each year is of concern to animal welfare advocates, public and regulators. A horse's previous athletic performance is a significant driver of retirement from racing. Racehorse performance can be measured in terms of the total number of starts, duration of racing and prize money earned. This study investigated Australian racing records for the 2005 and 2010 Victorian TB foal crops to identify factors associated with total number of starts, racing career duration, prize money earned and age of last race start‐up to the 10‐year‐old racing season. Racing Australia registered 4,577 TB horses born in Victoria in 2005 (n = 2,506) and 2010 (n = 2,071) that raced in Australia. Horses that started racing at 2‐years of age had fewer race starts in their first racing season but an increased total number of starts, prize money and duration of racing. The median age of last start (LS) was five (Q1 4; Q3 7) years. Horses that had won a race, had a maximum handicap rating of 61 or above and those racing over distances of more than 2,400 m had an increased racing career duration and an age of last race start greater than 6‐years of age. Horses participating in jumps races (n = 63) had the longest careers and older age of LS. These horses were more likely to have had a handicap rating over 80 and were just as likely to start their racing careers as 2‐years‐olds. [ABSTRACT FROM AUTHOR]

To determine the association between the presence of pet health insurance and the risk of euthanasia at the time of diagnosis for dogs with gastric dilatation-volvulus (GDV). Insurance status at the time of GDV diagnosis was sought for a cohort of 147 non-referred, confirmed cases of GDV that presented to the emergency department of a university-based veterinary hospital in Australia between 2008 and 2017. Insurance status was obtained from the medical record (n=18) or after contacting the owners by phone using a standardised questionnaire (n=129). Animal, clinical and outcome data was retrospectively compiled in a research database. The primary outcome measure was whether or not the dog was euthanised before surgery. The Mantel-Haenszel procedure was used to quantify the association between the presence of pet health insurance and the risk of euthanasia at the time of diagnosis for dogs with GDV, adjusting for the confounding effect of age at the time of presentation using Bayesian methods. Of the 69 dogs for which insurance information could be obtained, 10 (14%) cases were insured at the time of the GDV event and 59 (86%) cases were not. The majority of non-insured dogs (37/59; 63 (95% CI=50–74)%) were euthanised before surgery, while none (0 (95% CI=0–28)%) of the insured dogs were euthanised at that time (p<0.001). Of the 32 insured and non-insured dogs that underwent surgery, four dogs (13 (95% CI=5–28)%) did not survive to hospital discharge. Three dogs (9%) were euthanised during or after surgery and one dog (3%) experienced cardiopulmonary arrest during treatment. The majority of dogs for which insurance status was known did not survive to hospital discharge (41/69; 59%), and 90 (95% CI=7–96)% of deaths were caused by euthanasia prior to surgery. Uninsured dogs were 5.0 (95% credible interval=1.8–26) times more likely to undergo presurgical euthanasia compared with insured dogs. Euthanasia prior to treatment was most common cause of death in non-referred dogs with GDV; such euthanasia was entirely absent in the cohort of dogs that were insured. Financial considerations significantly contribute to mortality of dogs with GDV presented to an emergency room. Financial instruments to reduce the out-of-pocket expense for pet owners confronted with unexpected veterinary expenses have potential to reduce pet mortality. [ABSTRACT FROM AUTHOR]

Leptospirosis is a zoonosis, found worldwide, affecting many species of animals. We conducted a cross‐sectional study to estimate the prevalence of Leptospira borgpetersenii sv Hardjo and Leptospira interrogans sv Pomona in cattle in dairy herds in South‐Western Victoria, Australia. Fifty‐three herds were enrolled in the study. Urine samples were collected from 15 late‐lactation cows in each herd. A questionnaire was provided to herd managers at the time of each herd visit, asking them to describe the methods they used for controlling leptospirosis, including vaccination. Urine samples were pooled at the herd level and tested for leptospira spp. using real time PCR. Urine samples from individual cows within the positive pooled samples were then tested for Leptospira Hardjo and Leptospira Pomona using qPCR. Four of the 53 herds showed positive leptospirosis results giving an apparent prevalence of 8 (95% CI 2–18) leptospira‐positive herds per 100 herds at risk. Based on the 53 completed questionnaires, leptospirosis vaccination programs were not compliant with label directions in 36 of the 52 vaccinated herds: 69 (95% CI 55–81) of 100 herd managers that routinely vaccinated for leptospirosis did not comply with label directions. One herd was completely unvaccinated. Based on our findings, we estimate that approximately 10% of dairy farms in South‐Western Victoria are likely to be infected with leptospirosis. While most herds are vaccinating for leptospirosis, most are not doing so according to label directions. We conclude that herd managers need to be better educated regarding leptospirosis vaccination programs. [ABSTRACT FROM AUTHOR]

SnakeMap is a national cloud‐based, veterinary snakebite registry. It was designed to prospectively collect data of the clinical circumstances and temporospatial information on cases of snake envenomation in dogs and cats. We herein introduce the project and summarise the data from the first 4 years of SnakeMap. The registry is a veterinary community‐based online database allowing case entry from veterinary hospitals across Australia. Registry data comprise hospital characteristics, patient characteristics, envenoming snake type, treatment and outcome variables, including time and geolocation of the snake bite. We present summative information on select key variables from the SnakeMap registry (1 July 2015 to 30 June 2019). Twenty‐eight hospitals from 6 states/territories entered 624 cases into the registry, including 419 dogs (67%) and 205 cats (33%). Bite time was available in 216 animals of which 90 (42%) were reported to be bitten in the 3 hours between 03:00 pm and 05:59 pm; median bite to presentation interval was 60 (interquartile range [IQR] 30, 211) minutes in dogs and 95 (IQR 41, 238) minutes in cats. Bites occurred in the owner's yard in 356 dogs (85%) and 53 cats (26%). A snake venom detection kit was used in 172 cases (28%) and antivenom was administered in 523 cases (85%). Most animals (n = 534, 88%) survived to discharge (median hospitalisation of 25 [IQR 16, 62] hours). SnakeMap effectively collects relevant clinical data from dogs and cats with presumed snake bite and provides locally specific information on the epidemiology of snake envenomation in small animals. [ABSTRACT FROM AUTHOR]

Objective: To compare fixed‐time artificial insemination (FTAI) conception rates and serum progesterone concentrations at the time of FTAI for cows treated with the original Ovsynch program (OV) with those treated with a modified Ovsynch (MO) program. Design This was a randomised clinical trial. Methods: The study used five split‐calving, pasture‐based dairy herds in Southwest Victoria, Australia. Controls (n = 851) received the OV program: day 0 gonadotropin‐releasing hormone, day 7 prostaglandin F2α (PGF), day 9 gonadotropin‐releasing hormone and FTAI at day 10. The treatment group (n = 852) received a MO program with an additional prostaglandin injection on day 8. Subsets of cows from each group were sampled for blood progesterone at the time of FTAI. Results: The treatment group demonstrated FTAI conception rates that were 7% (95% confidence interval 2%–12%) greater than the control group. After adjusting for the effect of age, days in milk at Mating Start Date and herd, the odds of conception using FTAI was 1.36 (95% confidence interval 1.12–1.66) times greater for treatment group cows compared with control group cows. The variability of serum progesterone concentrations at the time of FTAI was significantly less for treatment group cows compared with control group cows. Conclusion: For Holstein‐Friesian and Holstein‐Friesian cross‐bred cows managed in pasture‐based dairy herds in southern Australia, a MO protocol, including a second injection of prostaglandin F2α on day 8, increased FTAI conception rates compared with cows receiving the OV protocol. [ABSTRACT FROM AUTHOR]

Objective: Australia is currently regarded as free of classical swine fever (CSF), a highly contagious disease of pigs caused by a pestivirus. This study aimed to provide additional evidence that the Victorian domestic pig population is free of CSF. Design: A structured representative sero‐prevalence survey of Victorian domestic pigs at slaughter. Method: Three‐hundred and ninety‐one pigs from 23 holdings were sampled at the time of slaughter between March 2016 and October 2017. Results: All samples were negative for CSF virus Ab on ELISA. Because of uncertainty in the sensitivity of the CSF Ab ELISA, estimates of the true prevalence of CSF were calculated using Bayesian methods. The median and upper bound of the 95% credible intervals for the true prevalence of CSF was zero when the diagnostic sensitivity of the CSF Ab ELISA was assumed to range from 0.75 to 0.95. Conclusion: These results provide evidence that the population of domestic pigs in Victoria in 2016‐2017 was free of CSF. [ABSTRACT FROM AUTHOR]

Aims: To provide herd managers with a set of decision rules allowing them to predict the likelihood that a juvenile bull is ready for Bull Breeding Soundness Evaluation (BBSE), or breeding, if bodyweight and scrotal circumference are known. Methods: This was a longitudinal study following two groups of young pasture-fed Holstein and Jersey bulls from northwest Tasmania, Australia. Individual scrotal circumference, bodyweight and semen characteristics were recorded at 6-8 weekly intervals, from 6-18 months of age. Classification and regression tree analyses were used to predict the probability that a bull had ≥70% normal sperm morphology based on scrotal circumference and bodyweight measurements. Results: Overall 1,661 scrotal circumference and bodyweight measurements were obtained, and 518 semen samples from 356 bulls were assessed for sperm morphology, from 16 examination sessions that took place between 29 May 2015 and 17 August 2016. Classification and regression tree analyses generated a decision tree for Holstein bulls with four node endpoints, and for Jersey bulls with three node endpoints. Diagnostic test performance showed that for Holstein bulls, using the node endpoints of scrotal circumference ≥27 cm and bodyweight ≥349 kg, 98% had ≥70% normal sperm (positive likelihood ratio 10.4; 95% CI = 2.7-41), and using the node endpoints of scrotal circumference ≥27 cm and bodyweight between 282-349 kg, 89% had ≥70% normal sperm (positive likelihood ratio 1.6; 95% CI = 0.9-2.6). For Jersey bulls, using the node endpoints of bodyweight ≥259 kg and scrotal circumference ≥29 cm, 88% had ≥70% normal sperm (positive likelihood ratio 3.4; 95% CI = 1.6-7.0). Conclusions: This study provides a set of relatively simple decision rules based on bodyweight and scrotal circumference measurements that allows herd managers to assess the likelihood that juvenile bulls are ready for BBSE or breeding. Abbreviations: BBSE: Bull breeding soundness evaluation; BRT: Boosted regression tree [ABSTRACT FROM AUTHOR]

Objective To describe outbreaks of sarcoptic mange caused by Sarcoptes scabiei in free-ranging koalas in Victoria (December 2008 to November 2015) and South Australia (October 2011 to September 2014). Methods Koalas affected by mange-like lesions were reported by wildlife carers, veterinary practitioners or State Government personnel to the Faculty of Veterinary and Agricultural Sciences at The University of Melbourne and the School of Animal and Veterinary Sciences at The University of Adelaide. Skin scrapings were taken from live and dead koalas and S. scabiei mites were identified. Tissues from necropsied koalas were examined histologically. Results Outbreaks of sarcoptic mange were found to occur in koalas from both Victoria (n = 29) and South Australia (n = 29) for the first time. The gross pathological and histopathological changes are described. Conclusion We present the first reported cases of sarcoptic mange outbreaks in free-ranging koalas. [ABSTRACT FROM AUTHOR]

This study quantified the extent of anthelmintic resistance (AR) in ascarid and strongylid nematodes against commonly used anthelmintics in Australian Thoroughbred horses. Faecal egg count reduction tests (FECRTs, n = 86) and egg reappearance period (ERP) tests were conducted on 22 farms across Australia. Faecal egg counts (FECs) were determined using the modified McMaster technique, and percent faecal egg count reduction (%FECR) was calculated using the Bayesian hierarchical model and hybrid Frequentist/Bayesian analysis method. The results were interpreted using old (published in 1992) and new (2023) research guidelines of the World Association for the Advancement of Veterinary Parasitology (WAAVP). The species composition of strongylid nematodes was detected utilising a DNA-metabarcoding method using pre- and post-treatment samples. Resistance was observed in strongylid nematodes to commonly used single-active and combination anthelmintics, including ivermectin (IVM %FECR range: 82%-92%; 95% lower credible interval (LCI) range: 80%-90%), abamectin (ABM: 73%-92%; 65%-88%), moxidectin (MOX: 89%-91%; 84%-89%), oxfendazole (OFZ: 0%-56%; 0%-31%) and its combination with pyrantel (OFZ + PYR: 0%-82%; 0%-78%). Resistance in Parascaris spp. was observed to IVM (10%-43%; 0%-36%), ABM (0%; 0%) and MOX (0%; 0%). When the new thresholds recommended by the WAAVP were used, AR was detected in six additional FECRTs for strongylids and three more tests for Parascaris spp., introducing resistance to OFZ and OFZ + PYR in the latter. Shortened ERPs (4-6 weeks) of strongylids were observed in 31 FECRTs in which AR was not detected at 2 weeks post-treatment for all the anthelmintics tested. Among cyathostomins, Cylicocyclus nassatus, Cylicostephanus longibursatus and Coronocyclus coronatus were the most prevalent species at 2 weeks post-treatment, whereas the main species appearing at five weeks following treatments with macrocyclic lactones were Cylicocyclus nassatus, Cylicostephanus longibursatus and Cylicocyclus ashworthi. After treatment with OFZ + PYR, the latter three, plus Coronocyclus coronatus and Cyathostomum catinatum, were detected at 5 weeks post-treatment. Overall, the study highlights the prevalence of AR in both ascarids and strongylid nematodes against commonly used anthelmintic products to control worms in Australian horses. The results indicate that ML combination products provided acceptable efficacy at 2 weeks. However, ERP calculations suggest that products work less effectively than previously measured. It is suggested to regularly monitor the efficacy of the anthelmintics and consider changing the worm control practices to better manage worms and AR in Australian horses., Competing Interests: Declaration of competing interest The authors of this manuscript are members of the Australian Equine Parasitology Advisory Panel (AEPAP), including Abdul Jabbar, Ghazanfar Abbas, Jenni Bauquier, Charles El-Hage, Abdul Ghafar and Ian Beveridge (The University of Melbourne), Anne Beasley (University of Queensland), Kristopher Hughes (Charles Sturt University), Caroline Jacobson and Emma McConnell (Murdoch University), Edwina Wilkes (Racing Victoria), Peter Carrigan and Lucy Cudmore (Scone Equine Hospital) and John Hurley (Swettenham Stud). Boehringer Ingelheim supported the panel. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

This study assessed worm control practices used by Australian Thoroughbred farm managers with an online questionnaire survey. The questionnaire comprised 52 questions (close-ended: 44; open-ended: 8) about farm demography and general husbandry practices, farm managers' knowledge of gastrointestinal nematodes (GIN) and their importance, diagnosis, worm control strategies and anthelmintics, anthelmintic resistance (AR) and grazing management. Following the pilot survey, the link for the questionnaire survey was sent to all (n = 657) registered members of the Thoroughbred Breeders Australia on 12th April 2020. The response rate for the questionnaire was 18.5% (122 of 675). The farm managers reported a good understanding of GIN and their importance in different age groups of horses as most respondents (70% of 122) perceived worm-related illness to be more important in young (i.e., foals, weanlings and yearlings) than adult (> 3 years old) horses. Although most respondents (93%, 113 of 122) used anthelmintics prophylactically to control GIN, only 15% (18 of 122) observed worm-related illness in their horses. Just under 40% of respondents were performing faecal egg counts, with less than 20% using the results of faecal egg counts to guide deworming decisions. The interval-based deworming strategy was the most common method (≥55% of 122 respondents) to control GIN in all age groups of horses. Macrocyclic lactones were the first choice of anthelmintics for all age groups of horses. Although the majority of respondents (88%, 107 of 122) perceived resistance in GIN against commonly used anthelmintics as an important issue in managing worms in horses, only 29% assessed the efficacy of anthelmintics and 91% (111 of 122) were unaware of AR on their properties. Grazing management practices, such as manure removal, were more frequently performed on smaller paddocks (<0.20 ha: 58%) than on larger paddocks (>0.20 ha: 18%). Multiple correspondence analyses showed that the likelihood of suboptimal worm control practices on small farms (n = ≤50 horses) was greater than that of medium (n = 51-100) and large (n = >100) farms. This study provides insights into the demography of Thoroughbred farms in Australia, husbandry practices used by stud managers and their knowledge about worms, control options and AR concerns, thereby paving the way for taking any initiatives to address the problem of AR in GIN of Australian Thoroughbred horses., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work stated in this report., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

This study reports the spatial and temporal distribution of ascarid and strongylid nematodes in Thoroughbred horses by age category across different climatic zones in Australia over an 18-month period. Faecal samples (n = 2046) from individual horses were analysed using the modified McMaster technique for faecal egg counts (FECs). Strongylids were identified using PCR-directed next-generation sequencing of the second internal transcribed spacer (ITS-2) of the nuclear ribosomal DNA. Yearlings had the highest prevalence (82%) of strongyle eggs followed by weanlings (79%), foals (58%), wet mares (49%) and dry mares (46%). For Parascaris spp., foals had the highest prevalence (35%) followed by weanlings (21%) and yearlings (10%). The highest mean FECs for Parascaris spp. were observed in foals (525 eggs per gram [EPG] of faeces) while those for strongyles were in yearlings (962 EPG). Among horses that were classified as adults at the time of sampling, 77% (860 of 1119) of mares were low (i.e., <250 EPG) strongyle egg-shedders. Mean strongyle FEC counts were highest in the Mediterranean (818 EPG) followed by summer (599 EPG), winter (442 EPG), and non-seasonal (413 EPG) rainfall zones. Twenty-six nematode species were detected, with Cylicostephanus longibursatus (26.5%), Cylicocyclus nassatus (23.7%) and Coronocyclus coronatus (20.5%) being the most frequently detected species. Their richness and relative abundance varied with horse age, season and climatic zone. In addition, Strongylus equinus and Triodontophorus spp. (T. brevicauda and T. serratus) were also detected. This comprehensive study elucidates spatial (climatic zone) and temporal (i.e., seasonal) trends in prevalence and burdens of intestinal nematodes in Australian horses using non-invasive conventional and molecular methods. The information presented in this study is crucial for developing integrated management strategies to control horse parasites in farmed horses., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work stated in this report., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

The study presents the results of a cross-sectional survey to describe the epidemiology of ascarid and strongylid nematodes in horses, the impact of diverse climatic conditions on parasite diversity and the levels of faecal egg shedding in different age groups of managed Thoroughbred horses. Individual faecal samples (n = 1377) collected from 62 Thoroughbred farms across four climatic zones in Australia were analysed using the modified McMaster technique for faecal egg counts (FECs) and strongylid nematodes were identified utilising PCR-directed next-generation sequencing (NGS) of the second internal transcribed spacer of the nuclear ribosomal DNA (ITS-2). Across all age groups, the prevalence of ascarid and strongylid nematodes was 12% (95% confidence interval 10-14%) and 72% (70-74%), respectively. Based on strongylid FECs, yearlings had the highest prevalence (89%) followed by weanlings (83%), foals (79%), wet mares (61%), dry mares (59%) and stallions (54%). However, for Parascaris spp., foals had the highest prevalence (46%) followed by weanlings (32%) and yearlings (13%). The highest mean FECs for Parascaris spp. were observed in foals (418 eggs per gram [EPG] of faeces) while those for strongylids were in yearlings (1002 EPG). Of the adult horses (mares and stallions), 67% (489 of 729) and 11% (77 of 729) were low (i.e., ≤250 EPG) and moderate (i.e., 251-500 EPG) strongylid egg-shedders, respectively. Strongylid egg shedding varied across climatic zones, with the highest mean FECs in the summer rainfall (723 EPG) followed by non-seasonal rainfall (629 EPG), winter rainfall (613 EPG), and Mediterranean (606 EPG) rainfall zones. Twenty-three nematode species were detected using NGS, with Cylicostephanus longibursatus (28%), Cylicocyclus nassatus (23%) and Coronocyclus coronatus (23%), being the most abundant species. Three species of Strongylus (i.e., S. vulgaris, S. equinus and S. edentatus) were also detected. The nemabiome composition, species richness and relative abundance varied within horse age and between climatic zones. These empirical findings provide a comprehensive understanding of the prevalence of parasites within horse populations and the multifaceted factors that influence their occurrence, thereby allowing for the formulation of tailored strategies aimed at parasite control in domestic horses., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work stated in this report., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

We conducted a retrospective cohort study to validate the efficacy of the Australian multitrait fertility estimated breeding value (EBV). We did this by determining its associations with phenotypic measures of reproductive performance (i.e., submission rate, first service conception rate, and early calving). Our secondary aim was to report the associations between these reproductive outcomes and management and climate-related factors hypothesized to affect fertility. Our study population included 38 pasture-based dairy herds from the northern Victorian irrigation region in Australia. We collected records for 86,974 cows with 219,156 lactations and 438,578 mating events from the date on which managers started herd recording until December 2016, comprising both fertility-related data such as insemination records, calving dates, and pregnancy test results, and systems-related data such as production, herd size, and calving pattern. We also collected hourly data from 2004 to 2017 from the closest available weather station to account for climate-related factors (i.e., temperature humidity index; THI). Multilevel Cox proportional hazard models were used to analyze time-to-event outcomes (days to first service, days to cow calving following the planned herd calving start date), and multilevel logistic regression models for binomial outcomes (conception to first service) in the Holstein-Friesian and Jersey breeds. A 1-unit increase in daughter fertility EBV was associated with a 5.4 and 8.2% increase in the daily hazard of calving in the Holstein-Friesian and Jersey breeds respectively. These are relative increases (i.e., a Holstein-Friesian herd with a 60% 6-wk in-calf rate would see an improvement to 63.2% with a 1-unit increase in herd fertility EBV). Similar results were obtained for submission and conception rate. Associations between 120-d milk yield and reproductive outcome were complicated by interactions with 120-d protein percentage and calving age, depending on the breed and outcome. In general, we found that the reproductive performance of high milk-yielding animals deteriorated faster with age than low milk-yielding animals, and high protein percentage exacerbated the differences between low and high milk-yielding animals. Climate-related factors were also associated with fertility, with a 1-unit increase in maximum THI decreasing first service conception rate by 1.2% for Holstein-Friesians but having no statistically significant association in the Jersey breed. However, THI had a negative association in both breeds on the daily hazard of calving. Our study validates the efficacy of the daughter fertility EBV for improving herd reproductive performance and identifies significant associations between 120-d milk and protein yields and THI on the fertility of Australian dairy cows., (The Authors. Published by Elsevier Inc. and Fass Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

The MilA ELISA has been identified as a highly effective diagnostic tool for the detection of Mycoplasma bovis specific antibodies and has been validated for serological use in previous studies. This study aimed to estimate the optimal cut-off and corresponding estimates of diagnostic sensitivity (DSe) and diagnostic specificity (DSp) of the MilA ELISA for testing bovine serum. Serum samples from 298 feedlot cattle from 14 feedlots across four Australian states were tested on entry into the feedlot and approximately 42 days later. The paired serum samples were tested with the MilA ELISA, BIO K302 (Bio-X Diagnostics, Belgium) and BIO K260 (Bio-X Diagnostics, Belgium). A cut-off of 135 AU was estimated to be optimal using Bayesian latent class analysis with three tests in multiple populations, accounting for conditional dependence between tests. At this cut-off, the DSe and DSp of the MilA ELISA were estimated to be 92.1 % (95 % highest probability density [HPD] interval: 87.4, 95.8) and 95.5 % (95 % HPD: 92.4, 97.8), respectively. The DSes of the BIO K260 and BIO K302 ELISAs were estimated to be 60.5 % (95 % HPD: 54.0, 66.9) and 44.6 % (95 % HPD: 38.7, 50.7), respectively. DSps were 95.6 % (95 % HPD: 92.9, 97.7) and 97.8 % (95 % HPD: 95.9, 99.0), respectively. Mycoplasma bovis seroprevalence was remarkably high at follow-up after 42 days on the feedlots. Overall, this study estimated a cut-off, DSe and DSp for the MilA ELISA with less dependence on prior information than previous analyses and demonstrated that the MilA ELISA has higher DSe than the BIO K260 and BIO K302 assays., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Infection with Mycoplasma bovis has been identified as a growing threat in dairy industries worldwide and there is an urgent need for an inexpensive and accurate herd-level screening tool to identify herds that have been exposed to M. bovis. This study aimed to evaluate the use of the MilA ELISA for testing bulk tank milk (BTM) samples for antibodies against M. bovis and estimate a suitable cut-off and diagnostic sensitivity (DSe) and specificity (DSp) for this assay. An optimal cut-off was then applied for investigating the geographical and seasonal distribution of infection with M. bovis in Australia. A total of 5554 BTM samples from 2683 dairy herds were collected during March, August and December 2017. BTM samples were tested in the MilA ELISA and a cut-off of 29 antibody units (AU) was estimated to be optimal using Bayesian latent class analysis which makes no assumption about the true disease status of herds under investigation. At this cut-off, the DSe and DSp were estimated to be 96.6% (95% highest probability density [HPD] interval: 87.0, 99.8) and 94.2% (95% HPD: 89.9, 97.4), respectively. The diagnostic specifications were found to vary markedly with stage of the production cycle, suggesting that targeted sampling was needed to maximize accuracy. We also found distinct differences in the apparent prevalence of M. bovis in different dairying regions, as well as seasonal variation. The highest apparent prevalence of M. bovis was observed in samples collected in March and an overall drop in the proportion of positive herds was seen from March to December. Overall, this study provides insights into the dynamics of BTM antibodies against M. bovis in Australian dairy herds and how the MilA ELISA can be applied for bulk tank milk testing., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Q fever is an important zoonotic disease perceived to be an occupational hazard for those working with livestock. Outbreaks involving large numbers of people are uncommon, but the increasing case incidence coupled with changing environmental and industry conditions that promote transmission of Q fever has raised concerns that large and serious outbreaks could become more frequent. The aim of this study was to use expert opinion to better understand how large Q fever outbreaks might occur in an Australian context and to document factors believed to be drivers of disease transmission. Focus groups were conducted with human and animal health professionals across several Australian states. All discussions were recorded, transcribed verbatim and imported into NVIVO for thematic analysis. Four anthropogenic risk factors (disease awareness, industry practices, land use, human behaviour) and three ecological risk factors (physical environment, agent dissemination, animal hosts) emerged from the data. Analysis of expert opinions pointed to the existence of numerous scenarios in which Q fever outbreaks could occur, many of which depict acquisition in the wider community outside of traditional at-risk occupations. This perception of the expansion of Q fever from occupational-acquisition to community-acquisition is driven by greater overarching economic, political and socio-cultural influences that govern the way in which people live and work. Findings from this study highlight that outbreaks are complex phenomena that involve the convergence of diverse elements, not just that of the pathogen and host, but also the physical, political and socioeconomic environments in which they interact. A review of the approaches to prevent and manage Q fever outbreaks will require a multisectorial approach and strengthening of community education, communication and engagement so that all stakeholders become an integrated part of outbreak mitigation and response., (© 2022 The Authors. Zoonoses and Public Health published by Wiley-VCH GmbH.)

The proportion of Thoroughbred (TB) horses that commence training and eventually race, is an important industry-level indicator of how successful it is at producing horses suitable for racing. It is also of interest to the wider community and is central to the issue of whether there is overbreeding in the Australian TB industry. This study investigated the training and racing records for the 2005 and 2010 Victorian TB foal crops to determine the proportion of TBs that train and race, and the age of entering training and first race start. Subsets of the foal crop were also examined to determine if premier yearling sale cohorts would produce selection bias. The Australian Stud Book (ASB) registered 7662 TB horses born in Victoria in 2005 (n = 4116) and 2010 (n = 3546). Of these, 5614 (73%) entered training and 4868 (64%) started in at least one race. Fourteen percent (n = 1045) of the study cohort had their first race start as 2-year-olds and 35% (n = 2644) had their first start as 3-year-olds. A higher proportion of TB horses that attended premier yearling sales entered training (93%) and raced (84%). This study established a baseline for training and racing milestones, such as the proportion and age that horses commenced training, and age of first start using population-level data. It also established that the use of subsets of the population can introduce selection bias., (© 2021 Australian Veterinary Association.)

The destinations of Thoroughbred (TB) racehorses exiting the racing industry is a high-profile issue with ethical and welfare implications of interest to both animal welfare groups and racing regulators. This cross-sectional study investigated the reasons that TBs temporarily or permanently exited racing and training in Australia in the 2017-2018 racing season and the outcomes for these horses post-racing. An online questionnaire was sent to the last registered trainers of a representative sample of 2,509 'inactive' TBs. Inactive horses were defined as those horses that were recorded as 'active' but had not trialled or raced in the last 6 months of the racing season or had an inactive status recorded in the Racing Australia database. Of the 1,750 responses received, the largest group of inactive TBs had permanently exited the racing industry (45% retired, 5.3% deceased). A relatively large group exited racing temporarily (43%) but participated in the racing industry in the following season. The reasons for retirement were predominantly voluntary, such as poor performance or owner's request. Almost one third of retirements were due to injuries with tendon or ligament problems the most frequently conditions listed. The median age at retirement was five (Q1 4; Q3 7) years. Extrapolation of the survey results to the population of horses racing or training in Australia in 2017-2018 (n = 37,750) show that that 17% of the population retire each year and 2.1% die. These estimates provide benchmarks for industry and animal welfare organisations to resource and measure the effectiveness of interventions., Competing Interests: The authors have read the journal’s policy and have the following competing interests to declare: Racing Victoria Ltd. provided support for MLF in the form of a thesis stipend. However, the stipend is part of a research contract for a separate project (Racing Vic 045083 15/16) and not associated with this study. AgriFutures Australia provided support for KS in the form of a thesis stipend. This does not alter our adherence to PLOS ONE policies on sharing data and materials. There are no patents, products in development or marketed products associated with this research to declare.

Identifying and quantifying the relative frequency of involuntary losses is an essential first step in developing fit-for-purpose herd health programmes. The objective of this study was to provide an estimate of the relative frequency of reasons for mortality among south-west Western Australian beef and dairy cattle, based on necropsy findings from a university-based veterinary pathology referral centre over 38 years. A total of 904 cattle were submitted for postmortem examination throughout the study period. Gastrointestinal, cardiopulmonary and reproductive conditions were the most common causes of mortality in cattle submitted for necropsy at Murdoch University for the period 1981-2018. In dairy cattle, the common problems were gastrointestinal (bloat, abomasal displacements) 18% (59/320), cardiovascular (traumatic reticulo-pericarditis) 9% (30/320) and respiratory conditions (pneumonia) 8% (27/320). In beef cattle, the most common conditions were gastrointestinal (bloat, rumen acidosis) 11% (39/358), reproductive (metritis) 11% (38/358), cardiovascular (traumatic reticulo-pericarditis) 7% (25/358), respiratory (pneumonia) 7% (24/358), lameness (fractures) 6%, (21/358) and hepatobiliary conditions (blue-green algae poisoning, hepatotoxicity) 6% (21/358). Selection bias and missing data were potential confounders in this study. Although necropsy investigations provide useful information on animal mortalities and avenues for future herd health programmes, there is a need to standardise data capture methods and disease definition criteria, and conduct more detailed recording of data both at the farm level and at necropsy diagnostic centres., (© 2021 Australian Veterinary Association.)

Reproductive performance in dairy cattle has declined over the last 50 years as an unintended consequence of selection for high milk yield. Since the early 2000s, dairy geneticists have released successive versions of fertility estimated breeding values (EBV) to assist in reversing this trend. At the herd level, fertility EBV can help managers accelerate improvements in reproductive performance by acting as a second selection criteria when used in tandem with a breeding index. However, use of the fertility EBV in sire selection currently varies between herd managers. The aim of this study was to better understand the reasons why herd managers choose or do not choose to select high-fertility EBV sires, using the Theory of Planned Behavior (TPB) as a social research framework. Thirty-five Victorian dairy herd managers were recruited as part of a larger study investigating the daughter fertility Australian Breeding Value and interviewed using a series of questions examining TPB constructs. The interviews were recorded and transcribed using template analysis. A wide range of herd manager types were enrolled into the study, with representation from diverse systems. Out of the 35 herd managers, 27 included fertility in their list of high-priority breeding objectives. A wide variation in results was consistent with previous studies that have demonstrated marked heterogeneity in herd manager attitudes toward bull selection. Herd manager-perceived barriers to selection of sires with high daughter fertility EBV included a lack of high daughter fertility bulls with other desirable traits, a lack of trust in the fertility EBV or in the Australian EBV system, difficulty in interpreting international proofs, information overload, semen prices, low bull reliability, and difficulty in understanding bull catalogs. Not all herd managers found the process problematic, however, particularly if a breeding consultant was employed to select all or most of the sires. Herd manager-perceived barriers for choosing to select daughter fertility as a breeding objective include a lack of awareness of the EBV, a lack of interest in genetics in general, low confidence in the impact of genetic selection for fertility, and a feeling that fertility was not important for their production system. The results of this study suggest that animal geneticists and on-farm service providers need to work together to allow the opportunities arising from appropriate use of fertility EBV to be realized more broadly across the dairy industry., (Copyright © 2021 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Currently, there is a paucity of data on the barriers for Australian Thoroughbred horses transitioning from stud farm to racetrack. This paper reports the reasons why horses failed to enter race training and documents their exit destinations. Biographical records of Australian Thoroughbred horses born in 2014 were investigated to determine the number of horses that had not officially entered race training by the start of the 4-year old racing season (1 August 2018). Of the 13,677 foals born in 2014, 66% had commenced training and 51% had raced before the beginning of their 4-year-old season in Australia. A sampling frame based on the post code of the premises where foals were born and records from Racing Australia were used to select a geographically representative sample of the 2014 Australian Thoroughbred foal crop (n = 4,124). From the population eligible for sampling 1,275 horses that had not entered training were enrolled in the survey and their breeders were sent an online questionnaire with follow-up phone calls for those who had not responded. Of the 633 responses (50% of 1275) the most frequent outcomes for horses were: death (38%, n = 239), participation in the racing industry in their 4-year old racing season (24%, n = 154) and retirement (16%, n = 100) either as Australian Stud Book (ASB) bloodstock (n = 17), or as horses rehomed outside the Thoroughbred industry (n = 83). Illness or injury was the most frequent reason for horses not entering race training that were ASB bloodstock, rehomed or deceased. There was a loss of traceability at the point of sale with most horses sold at 1 year of age. This study provides important information on the reasons, alternative outcomes and gaps in traceability for horses not entering training prior to the 4-year-old racing season., Competing Interests: The authors have read the journal’s policy and have the following competing interests to declare: Racing Victoria Ltd. provided support for MLF in the form of a thesis stipend. However, the stipend is part of a research contract for a separate project (Racing Vic 045083 15/16) and not associated with this study. Racing Victoria Ltd. also provided support to ASMW to work on an unrelated project with a separate research group in the Melbourne Veterinary School. This does not alter our adherence to PLOS ONE policies on sharing data and materials. There are no patents, products in development or marketed products associated with this research to declare.

Transmission network modelling to infer 'who infected whom' in infectious disease outbreaks is a highly active area of research. Outbreaks of foot-and-mouth disease have been a key focus of transmission network models that integrate genomic and epidemiological data. The aim of this study was to extend Lau's systematic Bayesian inference framework to incorporate additional parameters representing predominant species and numbers of animals held on a farm. Lau's Bayesian Markov chain Monte Carlo algorithm was reformulated, verified and pseudo-validated on 100 simulated outbreaks populated with demographic data Japan and Australia. The modified model was then implemented on genomic and epidemiological data from the 2010 outbreak of foot-and-mouth disease in Japan, and outputs compared to those from the SCOTTI model implemented in BEAST2. The modified model achieved improvements in overall accuracy when tested on the simulated outbreaks. When implemented on the actual outbreak data from Japan, infected farms that held predominantly pigs were estimated to have five times the transmissibility of infected cattle farms and be 49% less susceptible. The farm-level incubation period was 1 day shorter than the latent period, the timing of the seeding of the outbreak in Japan was inferred, as were key linkages between clusters and features of farms involved in widespread dissemination of this outbreak. To improve accessibility the modified model has been implemented as the R package 'BORIS' for use in future outbreaks., Competing Interests: The authors have declared that no competing interests exist.

Background: Epidemiological investigations were carried out following detection of an outbreak of megaoesophagus in Victorian Police working dogs in early 2018 and an increase in the number of canine megaoesophagus cases reported by companion animal veterinarians in Eastern Australia starting in late 2017. VetCompass Australia data were used to quantify the incidence of canine megaoesophagus for the period January 2012 to February 2018 and a matched case-control study carried out to identify individual animal risk factors for canine megaoesophagus in 2017-2018., Results: There was a 7-fold increase in the incidence rate of canine megaoesophagus from 2014 (0.11 [95% CI 0.02 to 0.58] cases per 100,000 dogs per day) to 2018 (0.82 [95% CI 0.19 to 4.2] cases per 100,000 dogs per day). Since 2013, the incidence of megaoesophagus in Australia has shown a seasonal pattern, with greater numbers of cases diagnosed during the warmer months of the year. In the case-control study, use of Mars Petcare Advance Dermocare as a source of food was 325 (95% CI 64 to 1644) times greater for cases, compared with controls., Conclusions: Our analyses provide evidence that the feeding of Advance Dermocare was responsible for the majority of cases in the outbreak of megaoesophagus in Eastern Australia in 2017-2018. The increase in the incidence rate of megaoesophagus in Australia since 2014-2015 warrants further investigation.

The objectives of this study were to assess antibody and cellular immune responses in first-lactation dairy heifers reared under a pasture-based production system and to investigate associations between immune competence and stress responsiveness, health, and productivity. A commercial vaccine was used to induce antibody and cellular immune responses and, based on measured responses, animals were classified as above average, average, and below average for each trait independently and in combination (overall immune competence). Overall immune competence phenotypic rankings were generated by combining standardized residual values for antibody and cellular responses measured in individual heifers. Cortisol responses to handling and yarding were used to assess stress responsiveness, worm egg counts were used to assess internal parasite burden, somatic cell counts to assess udder health and estimates of total daily milk volume, and milk fat and milk protein contents to assess productivity. A total of 393 Holstein-Friesian and Holstein-Friesian × Jersey crossbred heifers from 2 herds practicing seasonal calving in a pasture-fed production system were enrolled in the study. The immune competence phenotypes of individual heifers were assessed before their first mating and their subsequent performance during their first lactation was monitored. Animals with below-average antibody and cellular immune competence had higher serum cortisol concentrations compared with their counterparts following handling, suggesting they had a reduced ability to cope with management-induced stress. Furthermore, a significant negative (favorable) correlation was observed between antibody responses and stress responsiveness. Similarly, correlations between antibody responses and internal parasite burden were significant and negative (favorable). No correlations were observed between overall immune competence and milk yield, milk fat, and milk protein content., (Copyright © 2019 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

A number of transmission network models are available that combine genomic and epidemiological data to reconstruct networks of who infected whom during infectious disease outbreaks. For such models to reliably inform decision-making they must be transparently validated, robust, and capable of producing accurate predictions within the short data collection and inference timeframes typical of outbreak responses. A lack of transparent multi-model comparisons reduces confidence in the accuracy of transmission network model outputs, negatively impacting on their more widespread use as decision-support tools. We undertook a formal comparison of the performance of nine published transmission network models based on a set of foot-and-mouth disease outbreaks simulated in a previously free country, with corresponding simulated phylogenies and genomic samples from animals on infected premises. Of the transmission network models tested, Lau's systematic Bayesian integration framework was found to be the most accurate for inferring the transmission network and timing of exposures, correctly identifying the source of 73% of the infected premises (with 91% accuracy for sources with model support >0.80). The Structured COalescent Transmission Tree Inference provided the most accurate inference of molecular clock rates. This validation study points to which models might be reliably used to reconstruct similar future outbreaks and how to interpret the outputs to inform control. Further research could involve extending the best-performing models to explicitly represent within-host diversity so they can handle next-generation sequencing data, incorporating additional animal and farm-level covariates and combining predictions using Ensemble methods and other approaches.

This study involved a national cross-sectional survey of gastrointestinal nematodes (GINs) of alpacas in Australia. A total of 1545 fresh faecal samples were collected from both sexes of alpacas and processed for faecal egg counts (FEC) and molecular identification of nematodes using the multiplexed tandem PCR assay. Based on egg morphology, the overall prevalence of GINs was 66% while that for strongyles was 59%. The overall mean FEC was 276 eggs per gram (EPG) of faeces, with the highest count of 17,415 EPG. Male alpacas had a higher prevalence (68%, 334/490) as well as mean FEC (328 ± 60 EPG) of GINs than females (63%, 602/954; 227 ± 26, respectively). Weaners had the highest prevalence (80%) whereas tuis had the highest FEC (402 EPG) of nematodes. The highest prevalence (77%, 293/383) and FEC (630 EPG) of GINs were observed in the summer rainfall zone followed by the Mediterranean-type rainfall, non-seasonal rainfall and winter rainfall zones. The characterisation of nematode DNA isolated from faeces revealed the occurrence of seven different GINs, including Camelostrongylus mentulatus, Cooperia spp., Haemonchus spp., Oesophagostomum spp., Ostertagia ostertagi, Teladorsagia circumcincta and Trichostrongylus spp. Besides, Nematodirus spp. and Trichuris spp. were also found during FECs. The prevalence of Haemonchus spp. was highest in the summer rainfall zone while that of C. mentulatus was highest in the Mediterranean-type rainfall, non-seasonal rainfall and winter rainfall zones. The findings of this study revealed that alpacas harbour many of the same nematodes as sheep and cattle.

We conducted a longitudinal survey on 13 alpaca farms in four climatic zones of Australia to understand the epidemiology of gastrointestinal nematodes (GINs) of alpacas. A total of 1688 fresh faecal samples were collected from both sexes of alpacas from May 2015 to April 2016 and processed for faecal egg counts (FEC) and molecular identification of eggs using the multiplexed-tandem PCR assay. Based on egg morphology, the overall prevalence of GINs was 61% while that for strongyles was 53%. The overall mean FEC was 168 eggs per gram (EPG) of faeces, with the highest count of 15,540 EPG. Weaners had the highest prevalence (73%) and mean FEC (295 EPG) of GINs followed by tuis, crias and adults. Alpacas in the winter rainfall zone had the highest prevalence (68%) as well as FEC (266 EPG) followed by Mediterranean-type, non-seasonal and summer rainfall zones. Trichostrongylus spp. (83%, 89/107), Haemonchus spp. (71%, 76/107) and Camelostrongylus mentulatus (63%, 67/107) were the three most common GINs of alpacas across all climatic zones. The mixed-effects zero-inflated negative binomial regression model used in this study showed that it could help to design parasite control interventions targeted at both the herd level and the individual alpaca level. The findings of this study showed that the epidemiology of GINs of alpacas is very similar to those of cattle and sheep, and careful attention should be paid when designing control strategies for domestic ruminants co-grazing with alpacas.

This study aimed to assess current worm control practices used by Australian alpaca farmers with an online questionnaire survey. The questionnaire contained questions about farm demography and general husbandry practices, farmers' knowledge about gastrointestinal nematodes (GINs) and their importance, the use of worm control strategies and anthelmintics, and grazing management. A link for the questionnaire survey was sent to all (n = 954) registered members of the Australian Alpaca Association in July 2015. The response rate for the questionnaire was 25% (239/954). The majority of respondents were from small (≤ 50 alpacas; 64%, 153/239) followed by medium (50-100 alpacas; 24%, 57/239) and large (>100 alpacas; 12%, 29/239) farms. Findings revealed that the majority of respondents kept Huacaya alpacas to produce high-quality fibre and alpacas were usually kept with other domestic ruminants (e.g. cattle and sheep). Although half of alpaca farmers (114/220) perceived that GINs were an important health problem of alpacas, with Haemonchus spp. being the most common nematode, the majority of them (174/220) used anthelmintics for nematode control. Macrocyclic lactones, a commercial combination of four anthelmintics (abamectin, albendazole, closantel and levamisole) and monepantel were the three most commonly used dewormers by Australian alpaca farmers. Although a significant proportion (166/213) of respondents used a quarantine drench for alpacas, very few respondents were aware of strategic deworming and the issue of anthelmintic resistance. Alpaca farmers mostly used anthelmintics at the dose rate recommended for sheep (47%, 79/167) and cattle (9%, 15/167), though some used 1.5 (31%, 51/167) and 2 (13%, 22/167) times the dose rate recommended for sheep. The majority of small herds used anthelmintics at the dose rate recommended for sheep and cattle while medium and large herds used anthelmintics at 1.5 to 2 times the dose rate recommended for sheep. This study provides invaluable insights into the demography of alpaca farms in Australia, husbandry practices used by alpaca farmers and their knowledge about worms and their control, thereby paving the way for developing guidelines for the control of GINs of alpacas., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Gastrointestinal nematodes (GINs) can cause significant economic losses in alpacas due to lowered production of fibre and meat. Although no anthelmintics are registered for use in alpacas, various classes of anthelmintics are frequently used to control parasitic gastroenteritis in alpacas in Australia and other countries. Very little is known about the current worm control practices as well as the efficacy of anthelmintics used against common GINs of alpacas. This study aimed to assess the existing worm control practices used by Australian alpaca farmers and to quantify the efficacy of commonly used anthelmintics against GINs of alpacas., Methods: An online questionnaire survey was conducted to assess current worm control practices on 97 Australian alpaca farms, with an emphasis on the use of anthelmintics. Of this group of 97 alpaca farms, 20 were selected to assess the efficacy of eight anthelmintics and/or their combinations (closantel, fenbendazole ivermectin, monepantel, moxidectin and a combination of levamisole, closantel, albendazole, abamectin) using the faecal egg count reduction test (FECRT). A multiplexed-tandem PCR (MT-PCR) was used to identify the prevalent nematode genera/species., Results: The response rate for the questionnaire was 94% (91/97). Almost half of the respondents kept alpacas with sheep and cattle, and 26% of respondents allowed alpacas to co-graze with these ruminants. Although only 63% respondents perceived worms to be an important health concern for alpacas, the majority of respondents (89%) used anthelmintics to control GINs of alpacas. The commonly used anthelmintics were macrocyclic lactones, monepantel, benzimidazoles, levamisole, closantel and their combinations, and they were typically administered at the dose rate recommended for sheep. The FECRT results showed that a combination of levamisole, closantel, albendazole and abamectin was the most effective dewormer followed by single drugs, including monepantel, moxidectin, closantel, fenbendazole and ivermectin. Haemonchus spp. were the most commonly resistant nematodes followed by Trichostrongylus spp., Camelostrongylus mentulatus, Ostertagia ostertagi and Cooperia spp., Conclusions: This is the first study aimed at assessing worm control practices and efficacy of commonly used anthelmintics in alpacas in Australia. Our findings document the extent of anthelmintics resistance on Australian alpaca farms and identify those anthelmintics that are still effective against GINs of alpacas.

Vaccination is increasingly being recognised as a potential tool to supplement 'stamping out' for controlling foot-and-mouth disease (FMD) outbreaks in non-endemic countries. Infectious disease simulation models provide the opportunity to determine how vaccination might be used in the face of an FMD outbreak. Previously, consistent relative benefits of specific vaccination strategies across different FMD simulation modelling platforms have been demonstrated, using a UK FMD outbreak scenario. We extended this work to assess the relative effectiveness of selected vaccination strategies in five countries: Australia, New Zealand, the USA, the UK and Canada. A comparable, but not identical, FMD outbreak scenario was developed for each country with initial seeding of Pan Asia type O FMD virus into an area with a relatively high density of livestock farms. A series of vaccination strategies (in addition to stamping out (SO)) were selected to evaluate key areas of interest from a disease response perspective, including timing of vaccination, species considerations (e.g. vaccination of only those farms with cattle), risk area vaccination and resources available for vaccination. The study found that vaccination used with SO was effective in reducing epidemic size and duration in a severe outbreak situation. Early vaccination and unconstrained resources for vaccination consistently outperformed other strategies. Vaccination of only those farms with cattle produced comparable results, with some countries demonstrating that this could be as effective as all species vaccination. Restriction of vaccination to higher risk areas was less effective than other strategies. This study demonstrates consistency in the relative effectiveness of selected vaccination strategies under different outbreak start up conditions conditional on the assumption that each of the simulation models provide a realistic estimation of FMD virus spread. Preferred outbreak management approaches must however balance the principles identified in this study, working to clearly defined outbreak management objectives, while having a good understanding of logistic requirements and the socio-economic implications of different control measures.

Researchers from Australia, New Zealand, Canada and the United States collaborated to validate their foot and mouth disease models--AusSpread, InterSpread Plus and the North American Animal Disease Spread Model--in an effort to build confidence in their use as decision-support tools. The final stage of this project involved using the three models to simulate a number of disease outbreak scenarios, with data from the Republic of Ireland. The scenarios included an uncontrolled epidemic, and epidemics managed by combinations of stamping out and vaccination. The predicted numbers of infected premises, the duration of each epidemic, and the size of predicted outbreak areas were compared. Relative within-model between-scenario changes resulting from different control strategies or resource constraints in different scenarios were quantified and compared. Although there were differences between the models in absolute outcomes, between-scenario comparisons within each model were similar. In all three models, early use of ring vaccination resulted in the largest drop in number of infected premises compared with the standard stamping-out regimen. This consistency implies that the assumptions made by each of the three modelling teams were appropriate, which in turn serves to increase end-user confidence in predictions made by these models.

Aims: To describe results of a relative validation exercise using the three simulation models of foot-and-mouth disease (FMD) in use by the quadrilateral countries (QUADS; Australia, Canada, New Zealand, and United States of America; USA)., Methods: A hypothetical population of farms was constructed and, following the introduction of an FMD-like disease into a single farm, spread of disease was simulated using each of the three FMD simulation models used by the QUADS countries. A series of 11 scenarios was developed to systematically evaluate the key processes of disease transmission and control used by each of the three models. The predicted number of infected units and the size of predicted outbreak areas for each scenario and each model were compared using the Kruskal-Wallis test. Agreement among the three models in terms of geographical areas predicted to become infected were quantified using Fleiss' Kappa statistic., Results: Although there were statistically significant differences in model outputs in terms of the numbers of units predicted to become infected, the temporal onset of infection throughout the simulation period, and the spatial distribution of infected units, these differences were generally small and would have resulted in the same (or similar) management decisions being adopted in each case., Conclusions: Agreement among the three models in terms of the numbers of premises predicted to become infected, the temporal onset of infection throughout the simulation period, and the spatial distribution of infected premises provides evidence that each of the model developers are consistent in their approach to simulating the spread of disease throughout a population of susceptible individuals. This consistency implies that the assumptions taken by each development team are appropriate, which in turn serves to increase end-user confidence in model predictions., Clinical Relevance: Relative validation is one of a number of steps that can be undertaken to increase end-user confidence in predictions made by infectious disease models.

Distribution of finite levels of resources between multiple competing tasks can be a challenging problem. Resources need to be distributed across time periods and geographic locations to increase the probability of detection of a disease incursion or significant change in disease pattern. Efforts should focus primarily on areas and populations where risk factors for a given disease reach relatively high levels. In order to target resources into these areas, the overall risk level can be evaluated periodically across locations to create a dynamic national risk landscape. Methods are described to integrate the levels of various risk factors into an overall risk score for each area, to account for the certainty or variability around those measures and then to allocate surveillance resources across this risk landscape. In addition to targeting resources into high risk areas, surveillance continues in lower risk areas where there is a small yet positive chance of disease occurrence. In this paper we describe the application of portfolio theory concepts, routinely used in finance, to design surveillance portfolios for a series of examples. The appropriate level of resource investment is chosen for each disease or geographical area and time period given the degree of disease risk and uncertainty present.