Foal Crop Research Articles

Determinants of Thoroughbred yearling sales price in the UK

AbstractBackgroundIndustry‐level figures suggest that up to two‐thirds of Thoroughbred breeding operations in the UK are unprofitable and that around half of sales transactions of Thoroughbred yearlings, commercial breeders’ predominant income source, return a loss. The industry strategy currently endorses investment in stallion covering fee; however, to date, a comprehensive evaluation of sales price determinants in the UK setting is lacking and could better inform economic decision making to improve profitability.MethodsSales catalogue and Weatherbys’ stud book data from all Thoroughbred yearlings sold at the 2020 Tattersalls October yearling sale in the UK were used to build a hedonic sales price model. Explanatory variables representing sire, dam, yearling and sales attributes were evaluated. The final model's accuracy was assessed using out‐of‐sample data from all yearlings sold in the equivalent 2021 sale.ResultsIn 2020, a total of 1506 catalogued yearlings, representing around 30% of the UK Thoroughbred foal crop, were sold, with a median price of £42,575 (interquartile range 15,750‒105,000; range 840‒3,570,000). The sires’ covering fee, maternal siblings’ race performance attributes, whether the yearling was the dams’ first foal, consignment size, catalogue book and day of sale within book significantly influenced auction price; however, relationships were complex with significant interaction and confounding observed. The mean model forecasting error was £2074. The use of data from only one sale could affect generalisability.ConclusionsThese novel findings can inform breeding decisions to maximise profitability, give context for current industry strategies and can inform valuations of breeding stock.

Minimal vertical transmission of Equid alphaherpesvirus 1 (EHV-1) in normal developing foals during a naturally occurring abortion outbreak

Equid alphaherpesvirus 1 (EHV-1) is a major cause of abortion or neonatal death in horses worldwide. Using an experimental EHV-1 abortion model, only a fraction of mares aborted and the remaining foals were delivered normally, with a normal neonatal development beyond day 10 (Gardiner et al. Vaccine 2012;30:6564-72). Interestingly, high EHV-1 (genome) abundance was identified in the fetal membranes of the normal foals. It was suggested that vertical viral transmission from dam to foal had occurred without apparent impairment of the foal. During a vast EHV-1 abortion outbreak among approximately 1000 broodmares on a single operation, approximately one quarter of the expected foal crop was lost. There were (late trimester) abortions or foals that died/were euthanized within 24 hours postpartum (pp) due to severe respiratory distress syndrome (group 1). There was a (for this farm) disproportionally large group of foals that died or were euthanized due to signs of maladjustment/placental insufficiency within 96 hours after parturition (group 2). Normal foals were also born which lived beyond 10 days without complications (group 3). Our aim was to test the following hypothesis, namely whether there is evidence of natural vertical EHV-1 transmission in foals with uncomplicated parturitions and normal pp development during an abortion outbreak. During this EHV-1abortion outbreak, we collected fetal membranes from any pregnancy outcome of groups 1 – 3. With pregnancies grouped according to gestational age in paddocks of 40 - 50 mares, unfavorable pregnancy outcome varied between paddocks. To avoid sampling bias, we matched for any group 1 or 2 pregnancy outcome within the same paddock with two group 3 outcome samples. Samples were fixed in formaldehyde and paraffin embedded. Tissue sections were prepared for DNA extraction, and EHV-1 genome abundance was determined by semiquantitative PCR assay (Hussey.et.al. J Vet Diagn Invest. 2006;18:335-42). Results were reported as ‘moderate abundance’ at cycle threshold (CT) <34; ‘low’ at CT (34-37), and negligible at CT>37-39. Samples were considered ‘undetectable’ if CT≥39. Viral genome copy numbers are reported as (moderate/low/negligible) abundance and the total number of samples per group. In group 1 abundance was 2/9/1 in 22 samples (54.4%); group 2: 0/3/0 in 15 samples (20.0%), and 0/2/4 in 85 samples (7.1%) in group 3. We conclude that there is minimal vertical EHV-1 carry-over in those foals that develop normally post-partum during an EHV-1 abortion outbreak. Whether carry-over is limited to the fetal membranes or whether EHV-1 reaches the respiratory tract for a productive period of shedding in the foals could now be investigated.

Date of birth and purchase price as foals or yearlings are associated with Thoroughbred flat race performance in the United Kingdom and Ireland.

BackgroundThoroughbred breeders aim to have foals born early in the season, but scientific evidence on the advantages for race performance is scarce and contradictory.MethodsThe association between date of birth and purchase price as foal/yearling, with race performance by the end of the second and third years of life of Thoroughbreds racing in flat races in the United Kingdom (UK) and Ireland (IRE) was assessed using negative binomial and zero‐inflated negative binomial models on the entire 2014–2015 UK/IRE foal crops (n = 28,282).ResultsIn total, 6666 and 9456 horses raced in UK/IRE flat racing by the end of their second and third years of life. Prize money and prize money per start decreased with each additional day beyond 1 January that the foal was born. Purchase price as foal and yearling was negatively associated with the number of races run, while it was positively associated with prize money and prize money per start by the end of the third year of life.ConclusionsFoals born early in the season had higher earnings by the end of their second and third years of life than foals born later. Differences were more marked among males than females. The most expensive horses sold as foals or yearlings ran fewer races but earned more prize money and prize money per start than less expensive horses. Results from this population‐based analyses may inform strategies and management practices aiming to maximise horses’ racing performance potential and increase financial returns.

DYNAMICS OF DEVELOPMENT AND CURRENT STATUS OF THE NOVOALEXANDROVSKY DRAFT HORSE AT THE BRANCH “DIBRIVSKY STUD FARM № 62” SE “UKRAINE HORSE BREEDING”

The article analyzes the genealogical structure of the Novolexandrov draft breed of the Dibrivsky stud farm No. 62. As of today, 49 representatives of this breed, including 3 breeding stallions, 28 mares of the main herd and foals are kept at the branch “Dibrivsky stud farm No. 62” of SE “Ukraine horse breeding”. The stallions belong to three male lines which are Koketlyvyi, Tantal and Hradus. There are two mare’s families that are 166 Repetytsiyi (n=9), Roznaryadky (n=3) and three groupsnamely 239 Tetivy (n=8), 176 Rudy (n=1), Faktury (n=2). These mare’s families and groups were formed precisely at the Dibrivsky stud farm. Four more groups have been formed that are Firma (n=5), Ryabinka (n=3), Zherukha (n=3) i Ryabushka line (n=2). The largest number of mares families belongs to the Tantal male line (23 heads), Koketlyvyi (7 heads), Hradus (5 heads) and to the Kapiten line, which went completely into the mare’s families, (1 mare). The variability of the measurements of the main stock of horses and the milk productivity of mares from 2015 to 2021 were studied. The body measurements of mares have increased significantly in recent years, which leads to the consolidation of representatives of the breed and contradicts the requirements for the measurements of the Novolexandrov draft breed. Twenty-three mares exceed the maximum threshold of the "withers height" indicator, which is 76.7% of the brood stock. At the Dibrivsky stud farm a seasonal milking of mares lasts from May 1 to October 1 (5 months or 150 days). The milk productivity of mares decreased by 275.6-454.6 liters from 2015 to 2021, the coefficient of variation increased from 18.33 to 38.90 with a decrease in the number of lactating mares. The question of the correlation between live weight and milk productivity is very relevant, especially during forming a dairy herd from mares of draft breeds which are characterized by high milkability. Many authors have studied the influence of live weight on dairy productivity, as one of the indicators of animal development. Formulas for calculating live weight are based on measurements such as withers height and chest girth. Accordingly, if the measurements increase, the live weight of the animal increases. The indicators of reproduction of mares of the main composition for 11 years were determined. The average fertility of mares for 11 years is 70.2%. The average yield of foals per 100 mares is 63.9% with 95.6% successful foaling. This foal crop can be justified by the dependence on the % of fertilized mares (r = 0.67; p&lt;0.01). This correlation was accurately observed in 2018-2019, with a fertilization rate of 54.5 and 55.2, the foal crop was 54.5 and 53.3 accordingly with 100% successful foaling. Losses of foals due to abortions, weak and stillborns have amounted to an average of 3.3%for 11 years, which does not exceed technological requirements (5%).

Factors associated with racing performance and career duration for Victorian-born Thoroughbreds.

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.

Participation of Victorian Thoroughbreds in the racing industry: a whole-of-population benchmark.

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.

Retrospective analysis of the population dynamics and racing outcomes of the 2014 and 2015 UK and Ireland Thoroughbred foal crops.

Up-to-date figures on early losses of Thoroughbreds from the racing industry can inform strategies to improve retention and incentivise traceability of Thoroughbreds during this early life period. Data on Thoroughbred mares bred in 2013-2014 and training, racing and sales information of their live offspring were analysed. The proportions and 95% confidence intervals (95% CI) of the entire 2014-2015 United Kingdom and Ireland foal crops that entered training, raced, were imported and/or exported between birth and the end of their third year of life, as well as the racing performance of these horses as 2- and 3-year-olds were described. A total of 20,661 mares produced 28,282 live foals. Of them, 47.2% (95% CI: 46.7-47.8; n = 13,354) entered training by the end of their third year of life. Of these, 10,595 (79.3%; 95% CI: 78.7-80.0) raced at least once. Around 20% (n = 5712) of horses were exported by the end of their third year of life, of which 3526 (61.7%) had been in training. The overall mortality during the study period was 7.6% (n = 2123). A considerable proportion of Thoroughbreds had not entered training by 3 years of age but of those that had, the proportion that raced at least once was high. Further research is needed to establish reasons for premature losses from the industry.

Descriptive analysis of Thoroughbred horses born in Victoria, Australia, in 2010; barriers to entering training and outcomes on exiting training and racing.

The reasons for Thoroughbred (TB) horses not entering training or exiting the racing industry, are of interest to regulators, welfare groups and the broader community. Speculation about the outcomes of these horses threatens the community acceptance, or social license, of the TB breeding and racing industries. A representative survey of the 2010 Victorian born TB foal crop was used to determine the outcomes and reasons for exit for horses that had not entered training, or had exited training and racing by eight years of age. Horses exported for racing or breeding (4%), or that were still actively racing (7%) at the start of the follow up period were excluded from the study. An online questionnaire was sent to breeders or trainers of 3,176 TB horses eligible for enrolment in the study. Of the 2,005 (63%) responses received, the two most frequent outcomes were that the horse had either been retired or rehomed (65%), or deceased (16%). For the 1,637 TB horses that had entered training, the majority of retirements were voluntary (59%), followed by involuntary retirements due to health disorders (28%). For TBs that did not have an industry record of entering training (n = 368), death (34%), or retirement or being rehomed (27%), were the most frequent barriers to entering training. The median age of retirement for TBs that raced was five (Q1 4; Q3 6) years regardless of sex, or whether their first race start was at two, three or four years of age. Relatively large numbers of horses voluntarily retiring at five-years of age suggests that industry-level, rather than individual horse-level factors are the predominant influences on racing career duration.

Born to run? Retrospective analysis of training and racing outcomes of the 2014 and 2015 UK Thoroughbred foal crops

Born to run? Retrospective analysis of training and racing outcomes of the 2014 and 2015 UK Thoroughbred foal crops

Barriers to entering race training before 4 years of age for Thoroughbred horses born in the 2014 Australian foal crop.

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.

Long distance transportation of equine oocytes

Genetic testing offers precise and accurate data to horse owners concerning their horse’s health and offers potential economic value increases of foal crops via genome-assisted selection. Despite availability of at least 96 commercially available markers, fewer than 20 are commonly used. This project seeks to identify the barriers to the incorporation of genomic tools in diverse equine operations. Based on studies examining public opinion of human medical testing, we expected that lack of genetic education and few industry requirements for testing may contribute to neutral or negative opinions regarding genomic tools for horses. We developed a 20 total question survey to capture demographic information such as facility size, type, and primary breed, as well as horse owner familiarity, use, and outlook regarding equine genetic testing. Question types included multiple choice, Likert-type scale, and open-ended response. Recruitment through county extension agents and breed organizations supplied a broad sampling of the Florida horse industry. Responses were collected from February through May 2019. Data showed that 25% of horse owners had genetically tested their horses (n = 60). Of these consumers, 80% rated the quality of their experience as “excellent” or “good” (n = 15). There was a significant positive association between genetic education and likelihood to genetically test. Most respondents (65%) were interested in receiving information regarding genetic testing. Study participants preferred to find materials on genetic testing through Web-based articles and veterinarians. Results of this study will provide researchers with critical knowledge of their audience’s needs and a roadmap to tailor future educational resources.

Needs Assessment: What Are the Barriers to Use of Equine Genetic Testing?

Genetic testing offers precise and accurate data to horse owners concerning their horse’s health and offers potential economic value increases of foal crops via genome-assisted selection. Despite availability of at least 96 commercially available markers, fewer than 20 are commonly used. This project seeks to identify the barriers to the incorporation of genomic tools in diverse equine operations. Based on studies examining public opinion of human medical testing, we expected that lack of genetic education and few industry requirements for testing may contribute to neutral or negative opinions regarding genomic tools for horses. We developed a 20 total question survey to capture demographic information such as facility size, type, and primary breed, as well as horse owner familiarity, use, and outlook regarding equine genetic testing. Question types included multiple choice, Likert-type scale, and open-ended response. Recruitment through county extension agents and breed organizations supplied a broad sampling of the Florida horse industry. Responses were collected from February through May 2019. Data showed that 25% of horse owners had genetically tested their horses (n = 60). Of these consumers, 80% rated the quality of their experience as “excellent” or “good” (n = 15). There was a significant positive association between genetic education and likelihood to genetically test. Most respondents (65%) were interested in receiving information regarding genetic testing. Study participants preferred to find materials on genetic testing through Web-based articles and veterinarians. Results of this study will provide researchers with critical knowledge of their audience’s needs and a roadmap to tailor future educational resources.

REGIONAL EPIZOOTOLOGY OF INFECTIOUS AND INVASIVE DISEASES OF HORSES

The analysis of infectious and invasive diseases of horses spread in the Republic of Sakha (Yakutia) was carried out. The data from the reports of the Department of Veterinary Medicine and the Republican Veterinary and Testing Laboratory for the period 1986-2017 was used. The main diseases of horses bred in herds in the conditions of Yakutia, which cause significant economic damage, are rhinopneumonia, salmonellosis, leptospirosis, horse strangles, strongylatoses and parascaridosis. These diseases reduce actual foal crops by 20-40% due to infectious abortions. Economic damage per 100 mares may amount to 800-1600 thousand rubles per year. Salmonellosis abortion was registered in 143 settlements of 22 districts, leptospirosis - in 199 settlements in 25 districts. Incidence of horse strangles accounts for 62%, mortality rate being from 4 to 22%. Circulation of the rhinopneumonia virus was noted in 99 settlements of 16 districts. The prevalence of strongylatoses and parascaridosis is 100 and 64.7%, respectively. The greatest concern for horses is caused by 6 species of gadflies of the genus Hybomitra. Species composition of bloodsucking mosquitoes of Central and Western Yakutia is represented by 14-15 species. The epizootic situation in the Republic of Sakha (Yakutia) with salmonellosis abortion, rhinopneumonia, leptospirosis, horse strangles, strongylatosis, parascaridosis and entomosis remains tense. It is necessary to develop and implement plans for the prevention of infectious and parasitic diseases using diagnostic stodies, effective vaccines, anthelmmtics and probiotics.

THE USE OF CRYO-FEED IN THE RATION OF DAIRY COWS AND HERD HORSES OF YAKUTIA

The paper presents testing results of feeding dry cows and horses with cryo-feed, preserved by using natural techniques, at winter grazing (tebenevka). Research into digestibility of nutrition substances of cow ration was carried out on 30 cows of Sirrrmental breed divided into three groups (control and two experimental ones, whose ration included 4 and 1.5 kg of cryo-feed respectively). The introduction of cryo-feed in the ration of cows increased the level of metabolizable energy and had a positive impact on the efficiency of energy metabolism. Cows of the 1 st experimental group, where cryo-feed accounted for 12% of the nutrition ration, showed 5.8% higher protein digestibility than the control group. Feeding cows with cryo-feed in the dry period contributed to the maintenance of reproductive qualities. The percentage of fertilization of cows was 90-100%. It was established that feeding horses on cryo-feed significantly increased their nutritional level at tebenevka in the winter time and fully met the need of animals in feeding elements. This marked a high horse feeding capacity per 1 ha of cryo-feed, which amounted to 129-142 horse days. The advantage in organic matter digestibility at tebenevka on cryo-feed accounted for 11.9%, dry matter - 10.48%, crude protein - 18.3%, crude fiber- 21.9%, crude fat - 13.3%, and nitrogen-free extractive substances - 11.7%. The energy supply of a horse organism per 100 kg of live weight was 32.6 MJ, which exceeded the norm by 14.5%. Better digestibility of nutrients of winter-green mass of oats compared to the grass stand was due to the high content of carotene and provitamin Е in plants preserved on the root by natural cold. During the study it was established that the actual foal crop increased by 12-14% at tebenevka with horses on cryo-feed compared to traditional technology.

Commercial equine production in New Zealand. 2. Growth and development of the equine athlete

During the past 20 years, there has been a contraction in the New Zealand Thoroughbred industry and, to a lesser extent, within the Standardbred industry. These changes have seen an increasing proportion of the market being associated with fewer larger commercial farms. Many of these farms manage their own mares, and the mares and foals of several clients. This, in turn, has increased the similarity of the management of breeding and young stock within New Zealand. The temperate climate allows the majority of the management of breeding and young stock to be pasture based. The predominant pasture is ryegrass–clover mix that has been demonstrated to provide adequate nutrition for growth and development. The temperate climate also permits management of horses at pasture year round, which is proposed to stimulate development of the musculoskeletal system. Apart from a brief period during weaning, most young stock remain at pasture from birth until the start of yearling preparation. Free access to pasture exercise provides the opportunity to stimulate the musculoskeletal system for the future challenges as a racehorse. The export focus of many of the equine industries heavily influences the management decisions. Despite the availability of good-quality pasture post-weaning, many foals receive up to 50% of the daily dietary energy requirement as concentrates, possibly reflecting the emphasis on early sales as yearlings and the drive to optimise growth. The observations of drench resistance of common internal parasites presents an emerging problem for pasture-based production systems. A large proportion of the Thoroughbred foal crop is exported as yearlings or ready to run 2-year-olds. There is an increasing trend for Standardbreds to be sold as yearlings and this has resulted in changes in the management of Standardbred young stock.

Biphasic appearance of corticated and decorticated ascarid egg shedding in untreated horse foals

Parascaris spp. infects foals worldwide and may cause airway inflammation in addition to small intestinal impaction and rupture. It is observed that acquired immunity eliminates ascarid burdens beginning at about 6 months of age, and current evidence suggests that a single parasite generation propagates in each foal crop. The purpose of this study was to monitor natural parasitic infections in untreated mixed breed horse foals over the course of 0–300 days of age. Fecal samples were collected monthly from all foals born in 2014 (n=13), beginning July 2014 through February 2015. Fecal egg counts (FECs) were performed in triplicates using the Mini-FLOTAC method. The foals were necropsied between 154 and 298 days of age and all intestinal ascarid were collected and identified to stage. Ascarid FECs exhibited a biphasic distribution with an initial peak at 91–120 days of age and, after a steady decline, a second, smaller peak at 241–300 days of age. Numbers of corticated and decorticated ascarid eggs were compared, with decorticated FECs remaining consistently low with a slight increase directly after the first corticated FEC peak. Overall, 4.36% of the total ascarid eggs counted were decorticated. Ascarid FECs showed a sharp peak in September, declined, and then steadily increased beginning in December and continuing through February. Upon necropsy, moderate to high number of ascarid specimens were recovered from foals between 8 and 10 months of age, coinciding with the second peak for the FECs. Eleven of the 13 foals harbored immature ascarid stages indicating a recent reinfection. However, these data demonstrates that apparently a second, smaller wave of infection is present in 8–10 month old foals. It may be of value to monitor egg counts in this age group to make sure that all parasite categories are well controlled.

An investigation of a recent outbreak of nocardioform placentitis caused abortions in horses

Nocardioform placentitis associated with gram positive branching actinomycetes caused a record number of abortions in mares diagnosed by the University of Kentucky Veterinary Diagnostic Laboratory (UKVDL) affecting the 2011 foal crop (2011 foal crop: the cohort of foals conceived during the 2010 breeding season). The goal of the present study is to make a comprehensive analysis of this outbreak in terms of frequencies of the bacteria causing nocardioform placentitis mediated abortions and to investigate the ages of fetuses, abortion months and breeding times. In the present study, characteristic slow-growing, pungent/soil odor gram positive branching actinomycetes were recovered in high numbers in placental specimens in 76 abortion cases diagnosed as nocardioform placentitis by pathologists. To determine the type of actinomycetes responsible for the abortions, PCR assays were performed on the gram positive branching bacilli. The most prominent actinomycetes species were Amycolatopsis spp. (37 cases, 48.7%) and Crossiella equi (C. equi) (22 cases, 28.9%). Six cases (7.9%) contained both Amycolatopsis spp., and C. equi. 10 isolates were unidentified by PCR assays and shown to have high DNA sequence homology to Streptomyces species, Microbacterium species, Nocardia species and Allokutzneria species, as evidenced by 16 rRNA gene sequencing and phylogenetic analysis. Nocardioform placentitis related abortions occurred mostly between December 2010 and April 2011 happening exclusively in the last trimester. Breeding time of aborted pregnancies ranged from March 2010 to July 2010, suggesting that if transmission of the actinomycetes agents occurred during breeding, it was not related to a specific season.

The association of 2‐year‐old training milestones with career length and racing success in a sample of Thoroughbred horses in New Zealand

There is increasing evidence that exercise early in life has a positive effect on musculoskeletal health. At present, there is little whole population research investigating the effect of racing as 2-year-olds on future racing career. To investigate the association between attaining training milestones as 2-year-olds with length of career and racing success in Thoroughbred horses in New Zealand. Retrospective data were obtained of the 2001/02-born Thoroughbred foal crop. The 3 training milestones were: registered with a trainer, trialled and raced. The association of the training milestones with career length was measured using the outcomes: number of race starts and number of years raced, in a Cox regression model. Logistic regression models analysed the association of the training milestones with the outcomes: won or placed in a race. Linear regression was performed to assess the association of training milestones with total career earnings. Of 4683 horses in the population; 3152 horses were registered with a trainer, 2661 horses trialled and 2109 horses raced. Horses that raced as 2-year-olds had significantly (P<0.001) more race starts than those first raced as 3-year-olds or older, this was also true when the 2-year-old year data were omitted. Horses that raced as 2-year-olds had significantly (P<0.001) more years racing. Horses registered with a trainer, trialled or raced as 2-year-olds were more likely to have won or been placed in a race than those that achieved the milestones as 3-year-olds or older. Horses that first trialled and raced as 2-year-olds had greater total earnings than those that first trialled or raced at a later age. Two-year-old training milestones had a strong association with positive racing career outcomes. Horses in training or racing as 2-year-olds may have better musculoskeletal health throughout life than horses that are first in training or racing at a later age.

Partial deletion of the LAMA3 gene is responsible for hereditary junctional epidermolysis bullosa in the American Saddlebred Horse

Laminin 5 is a heterotrimeric basement membrane protein integral to the structure and function of the dermal-epidermal junction. It consists of three glycoprotein subunits: the alpha3, beta3 and gamma2 chains, which are encoded by the LAMA3, LAMB3 and LAMC2 genes respectively. A mutation in any of these genes results in the condition known as hereditary junctional epidermolysis bullosa (JEB). A 6589-bp deletion spanning exons 24-27 was found in the LAMA3 gene in American Saddlebred foals born with the skin-blistering condition epitheliogenesis imperfecta. The deletion confirms that this autosomal recessive condition in the American Saddlebred Horse can indeed be classified as JEB and corresponds to Herlitz JEB in humans. A diagnostic test was developed and nine of 175 randomly selected American Saddlebred foals from the 2007 foal crop were found to be carriers of the mutation (frequency of 0.026).

Growth Rates in Thoroughbred Horses Raised in Florida

Summary Growth rates of thoroughbred horses are not as well defined as those of other farm animals, and only a few articles summarize growth of thoroughbred horses over a prolonged period. Body weight (BW), heart girth (HG), wither height (WH), body length (BL), and hip height (HH) of 128 thoroughbred horses (59 colts and 69 fillies) were recorded from birth to 15 months of age at 14- or 28-day intervals. Data were obtained from consecutive 20 foal crops. At birth (0 day), BW was 53.55 ± 5.20 kg (range, 39.04–67.19), HG was 0.82 ± 0.03 m (range, 0.75–0.90), WH was 1.02 ± 0.03 m (range, 0.93–1.10), BL was 0.74 ± 0.03 m (range, 0.67–0.82), and HH was 1.05 ± 0.03 m (range, 0.93–1.14). At weaning (112 ± 3 days), BW was 199.57 ± 13.58 kg (range, 163.44–234.26), HG was 1.29 ± 0.04 m (range, 1.19–1.37), WH was 1.27 ± 0.03 m (range, 1.21–1.35), BL was 1.17 ± 0.03 m (range, 1.08–1.30), and HH was 1.32 ± 0.03 m (range, 1.24–1.39). At 6 months (181 ± 4 days), BW was 237.16 ± 18.48 kg (range, 186.14–288.74), HG was 1.36 ± 0.04 m (range, 1.24–1.45), WH was 1.33 ± 0.03 m (range, 1.26–1.40), BL was 1.25 ± 0.03 m (range, 1.17–1.33), and HH was 1.38 ± 0.03 m (range, 1.28–1.44). At 12 months (361 ± 8 days), BW was 337.73 ± 26.61 kg (range, 267.86–394.98), HG was 1.56 ± 0.05 m (range, 1.41–1.66), WH was 1.45 ± 0.03 m (range, 1.36–1.55), BL was 1.42 ± 0.04 m (range, 1.31–1.51), and HH was 1.49 ± 0.03 m (range, 1.41–1.57). At 15 months (447 ± 8 days), BW was 392.48 ± 30.61 kg (range, 317.80–457.18), HG was 1.64 ± 0.05 m (range, 1.52–1.76), WH was 1.49 ± 0.03 m (range, 1.42–1.58), BL was 1.48 ± 0.04 m (range, 1.40–1.59), and HH was 1.53 ± 0.03 m (range, 1.46–1.62). Two regression equations (y 1 from birth to 112 days of age and y 2 from 113 to 450 days of age) were calculated. WT kg is estimated by y 1 = 1.28x + 57.82 (R 2 = 0.94) and y 2 = 0.57x + 133.28 (R 2 = 0.86). HG m is estimated by y l = 0.0041x + 0.86 (R 2 = 0.90) and y 2 = 0.0011x + 1.16 (R 2 = 0.84). WH m is estimated by y 1 = 0.0022x + 1.03 (R 2 = 0.85) and y 2 = 0.0006x + 1.22 (R 2 = 0.80). BL m is estimated by y 1 = 0.0038x + 0.77 (R 2 = 0.92) and y 2 = 0.0009x + 1.09 (R 2 = 0.85). HH m is estimated by y 1 = 0.0024x + 1.07 (R 2 = 0.87) and y 2 = 0.0006x + 1.27 (R 2 = 0.78).