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Item Turf track surface interaction with speed and musculoskeletal injury risk in Thoroughbred racehorses(John Wiley and Sons Ltd on behalf of EVJ Ltd, 2025-07-24) Legg KA; Gibson MJ; Gee EK; Rogers CWBackground: Injury modelling based on changes in speed and stride characteristics of racehorses has become a primary industry focus for the Thoroughbred racing industry. However, speed and stride characteristics are strongly associated with track condition; therefore, reliable quantification of surface variables for use in future models is imperative. Objectives: This study aimed to understand the interaction of objective turf track condition score (TCS) measurement with racing speed and injury in flat racing Thoroughbred horses. Study Design: Retrospective time series analysis. Methods: Race-day data from 16 flat racing seasons (2008/9–2023/24, n = 40,824 races) were used to compare monthly TCS (based on penetrometer measurements), the coefficient of variability (CV) for TCS, race speed (over the final 600 m) and the number of race starts. Injury data from 7 seasons (2015–17, 2019–24) were used to calculate the monthly incidence rate (IR per 1000 race starts) of musculoskeletal injury (MSI). A mixed effects linear model was used to assess the relationship between speed, TCS, race distance and horse rating. Results: Race starts (n = 437,506), TCS and speed showed strong seasonal fluctuations, with more starts, lower and more variable TCS (4, IQR 3–5, CV = 0.44) and higher race speed (16.7 m/s, IQR 16.1–17.2) in summer compared with winter (TCS 10, IQR 8–10, CV = 0.22, p < 0.001 and speed 15.1 m/s, IQR 14.3–15.8, p < 0.001). Race speed had a strong negative quadratic relationship with TCS (β₂ = −0.03, p < 0.001), a negative linear correlation with race distance and was positively correlated with horse rating. There were 433 MSI (IR = 2.22, 95% CI 2.20–2.44), with an immediate (0 lag time) positive association with seasonal changes in TCS (r = −0.28). Main Limitations: Low monthly numbers of MSI constrained analysis of interaction with track variables. Conclusions: TCS provides a reliable quantitative measure of track condition which could be used to refine future models of injury risk in racing Thoroughbreds.Item Insights into the pathogenesis of catastrophic spontaneous humeral fractures in first-lactation dairy cows(CSIRO Publishing, Australia, 2025-05-06) Wehrle-Martinez AS; Lawrence KE; Back PJ; Rogers CW; Gibson MJ; Dittmer KE; Eastwood CSpontaneous humeral fractures in first-lactation dairy cows have introduced significant challenges to the dairy industry in New Zealand, impacting animal welfare, farm economics, and veterinary practices. This review synthesizes current knowledge on the pathogenesis of these fractures and identifies potential key risk factors. The majority of bones from affected first-lactation dairy cows have osteoporosis, which is associated with inadequate bone formation and increased bone resorption. In addition, low total collagen content in bones from most affected dairy cows supports the hypothesis that inadequate bone formation is an important risk factor associated with humeral fractures in these cows. Spectroscopic analyses further confirmed a significant reduction in bone quality and strength. Novel findings suggest that low liver copper concentration in many of the affected cows' results from the mobilisation of copper to the bone. Although limited, the accumulated evidence suggests that to mitigate the incidence of catastrophic fractures, adequate nutrition (especially protein-energy) should be supplied during important growth periods. While significant progress has been made in understanding the cause of these fractures, many uncertainties and areas requiring further research remain.Item The genetic parameters of racing success and longevity in the New Zealand Thoroughbred racing industry(Taylor and Francis Group on behalf of the Royal Society Te Apārangi, New Zealand, 2025-04-23) Chin YY; Sneddon NW; Gibson MJ; Legg KA; Gee EK; Rogers CW; Handcock RWithin the Thoroughbred industry, individual success can be measured with races and prize money won. At an industry level, there is a requirement for horses to be able to race from a young age and have a sustained injury-free career. Therefore, the variance components of such traits were investigated within ASReml for 26,920 New Zealand Thoroughbred racehorses. Age at first competitive high-speed event (trial or race start) had high heritability (h2= 0.52 ± 0.02), and an inverse genetic correlation with career earnings (−0.40 ± 0.05) and number of wins (−0.35 ± 0.06). Career earnings (h2 = 0.24 ± 0.02) had positive genetic and phenotypic correlations (0.59 ± 0.004) with career length, implying that racing success could be a useful selection proxy for career length. Horses that started earlier had longer career length (−0.21 ± 0.07,–0.18 ± 0.01). The low heritability of career length (0.11 ± 0.01) reflects considerable environmental influence on this trait, reinforcing the importance of early training and exercise in increasing career length. Therefore, the optimal strategy is a selection programme focusing on racing success, which improves commercial appeal and is genetically correlated with longevity. A training and racing programme that encourage an early competitive high-speed event would optimise the phenotypic development of the musculoskeletal system and reduce injury risk.Item The Relationship Between Stature and Live Weight of Dairy Cows Between Birth and Maturity(MDPI (Base, Switzerland), 2025-03) Gibson MJ; Sneddon NW; Rogers CW; Back PJ; Dittmer KE; Martín NP; Bezerra LR; Lancaster PLactational and reproductive performance are strongly associated with cow live weight and capacity. However, there are limited data published describing capacity (thoracic) growth and the prediction of final stature and capacity from measurements at birth. Therefore, the aim of this study was to examine the relationship between stature and live weight of female dairy cattle between birth and maturity. Forty dairy cows, with records of stature and capacity from birth up until two years of age, underwent follow-up measurements for live weight, height at withers, wither-rump length, girth circumference and leg length on four occasions between 42 and 52 months of age. Measures of wither height, leg length and wither rump length at fourth mating had the strongest association with measures at birth (R2 > 0.90) compared to girth and live weight (R2 = 0.88 and 0.82, respectively). The weaker association between birth and maturity measures for girth is likely a reflection of the stronger relationship with live weight resulting in a later maturity (approximately 810 days) compared to linear measures such as height (approximately 730 days). Therefore, to maximise capacity, adequate nutrition is required until approximately 810 days of age when capacity growth is most sensitive to environmental input.Item Incidence and risk factors for limb fracture in greyhound racing in Western Australia(John Wiley and Sons Australia, Ltd on behalf of Australian Veterinary Association, 2024-10-04) Gibson MJ; Legg KA; Gee EK; Smet A; Medd J; McMullen C; Auld L; Rogers CWIdentification of risk factors for race day injury can improve greyhound welfare. Race day fractures are the most significant injury event and have the greatest negative impact on dog welfare and the industry's social license to operate. This study aimed to describe the incidence and risk factors for race-related fractures in greyhounds racing in Western Australia. Electronic extracts describing race level data and race day injuries were provided by Racing and Wagering Western Australia (RWWA). The incidence rate (IR) of fractures for all greyhound race starts in Western Australia from 1 January 2017-31/12/2023 was calculated per 1000 starts. Univariable and multivariable models using Poisson regression were used to calculate the IR ratio of fracture type based on race and greyhound-level factors. There were 198,008 racing starts and 662 (n = 643, 97.1% involving the limbs) fractures resulting in an IR of 3.3 fractures per 1000 starts (95%CI 3.1-3.6). Greyhounds that had an injury in their previous race were 2.3 times (95%CI1.4-4.3) more likely to have a forelimb fracture than greyhounds that did not have an injury (P = 0.013). The risk of tarsal bone fracture was greater in greyhounds older than 30 months and greyhounds that had not raced in the previous 15 days. Risk factors for fractures in the forelimb were associated with trauma after interference or dog collisions, whereas tarsal fractures were associated with strain and cyclic loading from race training/racing. Changes to racing structure, rules and policies based on these risk factors may help to reduce fracture incidence in racing greyhounds.Item The intrauterine effects of a maternal winter diet of either kale or fodder beet on measures of calf stature and bone morphology at birth(Taylor and Francis Group, 2024-10-09) Gibson MJ; Rogers CW; Back PJ; Dittmer KE; Wehrle-Martinez A; Dalley DE; Woods RRFodder beet and kale are commonly used winter crops in New Zealand dairy and dairy support farm systems. Fodder beet (FB) is known to have lower crude protein, phosphorus and calcium content compared to kale. The intrauterine effects of feeding FB during late pregnancy on bone growth and development in calves requires attention. This study aimed to examine the intrauterine effects of a maternal diet of either kale or FB on measures of calf stature and bone morphology at birth. In winters 2019 and 2020, two herds of pregnant Friesian ×Jersey cows were fed either kale (2019, 2020 n = 20) or FB (2019, 2020 n = 20) supplemented with pasture baleage. Calves born from these mobs were euthanised within ten days of birth and a forelimb and section of rib including the costochondral junction were harvested for peripheral quantitative computed tomography and histological analysis. Calves from the FB treatment had reduced bone density and strength compared to calves from the kale treatment (p <.05). The effect of a nutritional deficit on bone morphology at birth emphasises the importance of sufficient nutrition in pre-calving diets. Future research is required to examine the long-term impact of dam undernutrition on calf growth and production.Item Worms and welfare: Behavioural and physiological changes associated with gastrointestinal nematode parasitism in lambs.(Elsevier B.V., 2023-10-27) Hempstead MN; Waghorn TS; Gibson MJ; Sauermann CW; Ross AB; Cave VM; Sutherland MA; Marquetoux N; Hannaford R; Corner-Thomas RA; Sutherland IAParasitism with gastrointestinal nematodes (GIN) is a worldwide issue impacting negatively on animal production, health, and welfare. Therefore, early diagnostic signs of parasitism are required to allow for timely interventions. The objective of this study was to evaluate the behavioural and physiological changes in lambs associated with GIN infection. We used 30, 8-month-old Romney-cross wethers, that were administered anthelmintics until faecal egg counts (FEC) were zero and housed in an indoor facility. The study lasted 9 weeks, which comprised a 3-week pre-treatment, and a 6-week treatment phase. Lambs were randomly assigned to one of two treatments (n = 15/treatment) trickle-dosed with: 1) 1500 infective third stage larvae (L3) three days/week for 6 weeks (27,000 total L3; challenged), or 2) water 3 days/week for 6 weeks (control). Within each pen there were 5 pairs of lambs (balanced for liveweight), with each pair comprising a challenged and control lamb. Blood, faecal, and saliva samples were collected 1 week pre-treatment and weekly for 6 weeks of treatment. Behaviour was observed (e.g., feeding, lying, standing) from video-camera recordings using scan sampling every 5 min for 8 h, 1 day pre-treatment and on the day immediately prior to physiological sampling across the 6-week treatment phase (7 days in total). Accelerometers were attached to each lamb to continuously monitor behaviour from 3 weeks pre-treatment and for the remainder of the study. Liveweight, body condition, faecal soiling and faecal consistency scoring were performed weekly as was lipidomic analysis of plasma samples. From week 2 of treatment, challenged lambs spent less time feeding and more time lying than control lambs until week 5 of treatment (P ≤ 0.01). At week 3 of treatment, elevated lipids (mainly triglycerides and phospholipids), loose faeces and faecal soiling around the anus were observed in challenged lambs compared with controls (P ≤ 0.05). From week 4 of treatment, FEC were elevated in the challenged compared to control lambs (P ≤ 0.05). There was also lower liveweight gain at 4 and 5 weeks of treatment in the challenged lambs compared with control lambs (P ≤ 0.05). These results show a clear timeline of changes in behaviour (e.g., feeding and lying), lipids such as triglycerides, and digestive function (e.g., faecal soiling) suggestive of GIN subclinical disease, which show promise for use in future studies on early identification of subclinical GIN parasitism in lambs.Item Risk Factors for Horse Fatality in Thoroughbred Jumps Racing in New Zealand.(Elsevier B.V., 2023-10-01) Gibson MJ; Legg KA; Gee EK; Rogers CWThe aim of this study was to examine the race-, horse- and jockey-level risk factors for race day fatality in New Zealand Thoroughbred jumps racing using retrospective race day data from the 2011/12 to 2021/22 seasons (n = 8,970 starts). There were 51 race day fatalities resulting in an incidence rate of 5.7 per 1,000 starts (95% C.I. 4.3-7.5). The majority of fatalities were the result of fractures (44/51, 4.9 per 1,000 starts, 95% C.I. 3.7-6.6). Steeplechase and hurdle races had the same incidence of fatal fractures of 4.9 per 1,000 starts (95% C.I. 3.7-6.6, P > .05). Most (70.5%) of the fatal fractures were due to a horse falling during the race. In steeplechase races, horses running in races over 4,201 m were 5.0 times (95% C.I. 1.2-33.0) more likely to sustain a fatal fracture than horses in racing over shorter distances. In hurdle races, horses racing during spring were 2.2 times (95% C.I. 1.0-4.8) more likely to sustain a fatal fracture compared to winter. Due to the low number of suspected cardiac failures and fatal soft tissue injuries, risk factors for these fatalities could not be identified. These data provide a baseline to enable evidence-based regulatory changes and prospectively monitor the effectiveness of changes made.Item Career profile and pattern of racing for Thoroughbred jumps-racing horses in New Zealand(CSIRO Publishing, 2024-04-23) Gibson MJ; Legg KA; Gee EK; Chin YY; Rogers CW; Bryden WContext Racing structure and focus for racehorses differs across jurisdictions and is poorly described. In New Zealand and Australia, jumps racing accounts for a small proportion of total Thoroughbred races each year, as opposed to the larger jumps-racing (National Hunt) industry with purpose-bred horses found in the UK and Ireland. Aims This study aimed to describe the career profile and pattern of racing for Thoroughbred jumps-racing horses in New Zealand. Methods Metrics from every horse with a full jumps-racing career (n = 1276, 89% geldings) between the 2005/06 and 2021/22 racing seasons (n = 40,302 starts) were examined. Descriptive statistics, box plots and heat maps were used to describe the data, by using horse age as a proxy for career progression. Key results Jumps-racing horses had a median of 17 flat starts (IQR 9–30) before their first jumps-racing start. The median career of a jumps-racing horse was 3.7 years (IQR 2.3–5.2) and 29 starts (IQR 16–44). Older horses had a decreasing number of flat-racing starts and an increasing proportion of steeplechase-racing starts. However, the majority of horses still had at least one flat-race start per calendar year, often prior to the first jumps race. Most horses had one spell each season (length 194 days, IQR 124–259), and a condensed preparation length over the winter months, with a median of 14 days (IQR 10–21) between starts. Conclusion The career pattern for jumps-racing horses in New Zealand reflects the industry retention of horses with a prior career in flat racing into a secondary jumps-racing career. Successful horses have increased focus on preparation for the winter jumps-racing season. Implications Jumps racing provides a secondary racing career for some flat-racing horses, particularly geldings. This strategy reduces wastage of horses from the industry.Item Measures of Bone Morphology in the Medial and Lateral Condyles of the Metacarpus in Beef Cross Dairy Cattle at 8–12 and 24 Months of Age(MDPI (Basel, Switzerland), 2022-09-01) Gibson MJ; Hickson RE; Dittmer KE; Back PJ; Rogers CWBone morphology in the mid-diaphysis of the metacarpus in cattle and the effect of puberty and age has been well described. However, there is limited information on how age and not attaining puberty affects bone morphology in the epiphysis of the metacarpus. The metacarpus is comprised of the third and fourth metacarpal bones fused together to create a medial and lateral epiphysis. When a cow is in stance phase there is greater pressure on the medial claw; however, the effect of this difference in loading on bone has not been described. Therefore, the aim of this experiment was to describe bone morphology in the medial and lateral epiphysis of the metacarpus at the age of puberty in steers. The metacarpus was collected from beef cross dairy steers at approximately one and two years of age. The distal epiphysis of the metacarpus was scanned using peripheral quantitative computed tomography (pQCT). Measures were corrected for body weight and demonstrated a lack of bone growth cessation at one year of age. The lack of difference in bone morphology in the medial and lateral condyles of the distal metacarpus reflects the even loading distribution observed in the forelimb of cattle.