Preliminary Examination of the Biological and Industry Constraints on the Structure and Pattern of Thoroughbred Racing in New Zealand over Thirteen Seasons: 2005/06–2017/18

Abstract

This study aimed to examine thirteen seasons of flat racing starts (n = 388,964) in the context of an ecological system and identify metrics that describe the inherent characteristics and constraints of the New Zealand Thoroughbred racing industry. During the thirteen years examined, there was a 2–3% per year reduction in the number of races, starts and number of horses. There was a significant shift in the racing population with a greater number of fillies (aged 2–4 years) having a race start, and subsequent longer racing careers due to the inclusion of one more racing preparation post 2008 (p < 0.05). Additionally, there was an increasingly ageing population of racehorses. These changes resulted in more race starts in a career, but possibly because of biological constraints, there was no change in the number of race starts per season, starts per preparation, or days spelling between preparations (p < 0.05). There was no change in the proportion of horses having just one race start (14% of new entrants), indicating that the screening for suitability for a racing career remained consistent. These data identify key industry parameters which provide a basis for future modelling of intervention strategies to improve economic performance and reduce horse injury. Consideration of the racing industry as a bio-economic or ecological model provides framework to test how the industry may respond to intervention strategies and signal where changes in system dynamics may alter existing risk factors for injury.

Race-Level Reporting of Incidents Using an Online System during Three Seasons (2019/2020–2021/2022) of Thoroughbred Flat Racing in New Zealand

“…Overall, the racing population had a similar number of horses and age profile as previously reported for the 2015/16–2016/17 seasons. The increase in age profile follows a similar trend to what has been previously reported by Legg et al [ 8 ] indicating a growing population of older horses. There appeared to be a post-COVID-19 lockdown rebound in racing starts.…”

“…To test if there was an increasing proportion of older horses racing, horses were grouped into 2 age groups: <6 years old and ≥6 years old (based on the median age). The age distribution of racing horses was determined using Simpson’s Diversity Index using these 2 groups of horses as described by Legg, et al [ 8 ]. As the evenness of the number of racing horses in each group increases, Simpson’s Diversity Index increases.…”

The pattern of breeding and management within the New Zealand Thoroughbred breeding industry 2005–2015. 1. The stallion population

“…This annual reduction in the number of mares covered and foals born (1.8% per year) was reflected in the consistent annual reduction of horses entering the New Zealand racing industry during 2005-2015. During this period, there was an annual reduction of 2-3% in the number of horses entering racing, the number of starts and, the number of races each year (Legg et al 2021). These data support the hypothesis that the contraction in the lower end of the breeding market was associated with a reduction in the supply of racehorses for New Zealand's domestic racing industry.…”

“…The median (IQR) start date of breeding season in low-, medium-, high-priced and shuttle stallions that stood at stud located in upper North Island (Northland, South Auckland, Waikato), central and lower North Island (Taranaki, Manawatu, Hawke's Bay, Wairarapa, Wellington) and South Island (Canterbury, Southland, Otago). is uncertain as official export figures do not demonstrate a subsequent increase in export from this foal crop and there was no proportionate increase in the number of Thoroughbred races and horses in New Zealand (Legg et al 2021). Two distinct populations were described within New Zealand breeding industry, a domestic market (either breed to race, or sell as a trials winner), which is predominantly supplied by lower-cost stallions, and a population focused on breeding to sell as yearlings, predominantly to the export market, typically supplied by foals sired by highpriced stallions (Rogers and Gee 2011).…”

Race-Level Reporting of Incidents during Two Seasons (2015/16 to 2016/17) of Harness Racing in New Zealand

“…The difference in the reported fracture incidence between Thoroughbred racing and harness racing highlights the differences in the pattern and magnitude of load accumulated and the intensity of exercise between codes during both training and racing [ 1 ]. The harness racing horses had a median of 7 race starts per season over 2200 m, which was greater than the number of starts and race distance (5 starts/year, 1400 m) reported in the New Zealand Thoroughbred racing industry [ 13 , 16 ]. While harness racing horses in New Zealand typically acquire a greater number of load cycles during training and racing [ 5 , 17 ], the nature and magnitude of the load on the distal limb, and the first phalanx and metacarpophalangeal joint specifically, is less for the trotting/pacing compared to galloping [ 18 ].…”