Stud management involves the systematic and strategic breeding of horses to enhance desirable traits, maintain genetic diversity, and ensure the health and welfare of both mares and stallions. This practice encompasses a range of activities, including the selection of breeding pairs, monitoring of reproductive health, and management of breeding cycles. Key aspects of stud management include assessing genetic compatibility, managing nutrition and health care, and implementing breeding technologies such as artificial insemination or embryo transfer. Effective stud management requires a comprehensive understanding of equine genetics, reproductive physiology, and husbandry practices. This page gathers peer-reviewed research studies and scholarly articles that explore various facets of stud management, including genetic evaluation, reproductive technologies, and the impact of management practices on breeding outcomes.
Bosh KA, Powell D, Shelton B, Zent W.To improve efficiency at the farm level, a better understanding of how farm management factors impact reproductive performance is important. Objective: To assess reproductive efficiency and effectiveness among Thoroughbred mares in central Kentucky. Methods: A cohort of 1011 mares on 13 farms in central Kentucky was followed during the 2004 mating and 2005 foaling season. Information on farm level practices was collected via interviews with farm managers. Reproductive records were collected for each mare mated to obtain information on mare characteristics. The influence of mare age and status ...
Rogers CW, Cogger N.To examine the on-farm biosecurity practices of a group of commercial Thoroughbred stud farms in the North Island of New Zealand, in the absence of an exotic disease outbreak. Methods: A cross-sectional survey of biosecurity practices was conducted during the 2006/2007 Thoroughbred breeding season, and consisted of data from commercial Thoroughbred farms in the North Island of New Zealand standing a stallion. Data were collected on-farm by a single interviewer, using 17 open, closed and multiple-choice questions examining general farm/operation size and features, general animal health and bios...
Sharma S, Davies Morel MC, Dhaliwal GS.Decreased reproductive performance due to summer stress is a well known phenomenon in farm livestock. Whether this occurs in the mare and specifically how this might affect postpartum reproductive activity and performance, especially at Foal Heat (FH), is unknown. This study, therefore, aims to investigate this and the factors that might affect postpartum reproductive activity. Reproductive records of 228 Thoroughbred mares (694 mare years) bred in subtropical north-western India were retrospectively analysed. Overt oestrous activity occurred within 21 d postpartum in 92.94% (645/694) of mares...
Ntafis V, Fragkiadaki E, Xylouri E, Omirou A, Lavazza A, Martella V.Severe outbreaks of diarrhoeic syndrome occurred in young foals at the same stud farm during two consecutive breeding periods namely spring 2006 and 2007. Rotavirus-like particles were detected by electron microscopy in the faeces of the affected foals and group A rotavirus infection was confirmed by Reverse-Transcription (RT)-PCR with selected sets of rotavirus-specific primers. Sequence analysis of the genes encoding the outer capsid rotavirus proteins VP7 and VP4 enabled classification of the viruses as G3AP[12] and revealed that the viruses were highly similar to recently reported equine r...
Lind EO, Christensson D.In the last few years stud farms have experienced increasing problems with Parascaris equorum infections in foals despite intensive deworming programs. This has led to the question as to whether the anthelmintic drugs used against this parasite are failing. This study aimed to investigate the efficacy of ivermectin, fenbendazole and pyrantel on the faecal output of ascarid eggs of foals. Methods: A Faecal Egg Count Reduction Test (FECRT) was performed on nine large studs in Sweden. Anthelmintic drugs were given orally and faecal samples were examined for ascarid eggs on the day of deworming an...
Cuervo-Arango J, Clark A.The mare is a seasonally polyestrus breeder. In early spring, the mare enters a "transition period" between the anovulatory season and the first ovulation of the year. This period is characterized by irregular estrus cycles and high incidence of regressing dominant follicles. There is a belief that pregnancy rates resulting from the first ovulation of the season is lower than in subsequent ovulations, however this has never been studied critically. Progestagens are often used as an aid to manage the transition period. The objective of this study was to compare pregnancy rates of mares from the...
Thirstrup JP, Bach LA, Loeschcke V, Pertoldi C.In this study, we performed a population viability analysis on 3 domestic horse breeds (Equus caballus) of Danish origin, namely, the Frederiksborg, the Knabstrupper, and the Jutland breeds. Because of their small population sizes, these breeds are considered endangered. The Vortex software simulation package was used for the population viability analysis. First, we investigated the future viability of these breeds based on present demographic and environmental parameters. Second, a sensitivity analysis revealed the most important variables for the viability of these breeds. Third, we examined...
Sharma S, Dhaliwal GS, Dadarwal D.Service records of 253 mares (1181 mare-years) spanning over 7 consecutive years, from nine organized Thoroughbred stud farms, situated in the subtropical northwestern India were retrospectively analyzed to assess their reproductive performance. The overall per cycle pregnancy rate at Day 16 and overall foaling rates were 50.30% and 68.95%, respectively, and were significantly higher in mares aged 3-7 years than > or =18 years old mares. The late embryonic losses (9.86%) that occurred between Days 16 and 39 post-ovulation contributed more than 50% of the overall detected pregnancy losses (19.1...
Pisseri F, Bertoli A, Nardoni S, Pinto L, Pistelli L, Guidi G, Mancianti F.Dermatophytes are a group of keratinophilic and keratinolytic molds, some of which are responsible for ringworm. Among them Trichophyton equinum, which mostly infects equids, can cause extensive outbreaks in stud farms. The conventional treatment of equine trichophytosis is topic, based upon medicated shampoos to reduce the spread of infection among the animals. Nevertheless the popularity of phytotherapy is at an all-time peak, and the interest for natural alternatives or complements to conventional drug therapy is challenging both in human and veterinary field. Among herbal remedia Tea Tree ...
Posta J, Komlósi I, Mihók S.The aims of this study were to estimate phenotypic and genetic parameters for a range of traits in Hungarian Sport Horses, and to compare several methods of estimating breeding value (BV) in this breed. The analyses were based on the Hungarian Sport Horse Studbook, results of self-performance tests (SPTs) and show-jumping competition results. An SPT comprises subjective judgement of conformation traits, movement analysis traits and free-jumping performance, assessed via ordinal scores. Genetic parameters of SPTs were estimated with an animal model. Different measurements of the competition per...
Elliott C, Morton J, Chopin J.Foaling data from 348 Thoroughbred foals born on a commercial stud were analysed to investigate interrelationships among mare age, parity, gestation length, foal sex, placental weight, and foal birth weight. Placental weight was positively correlated with foal birth weight up to a threshold of 6.5 kg; above this, placental weight was not significantly associated with foal birth weight. Placental weight was assessed, including the amniotic membranes and umbilical cord as well as the allantochorion. Using path analysis, parity was positively associated with foal birth weight both directly and th...
Sevinc F, Maden M, Kumas C, Sevinc M, Ekici OD.Blood and serum samples were taken from 481 horses, from a stud farm or a racecourse, and tested by microscopic examination of blood smears and cELISA for Theileria equi (T. equi) and Babesia caballi (B. caballi) infections. At the time of sampling, animals were also examined for tick infestations and clinical disease, which were not observed in any of the sampled horses. During the microscopic examination of thin blood smears, parasites were detected in the three horses from the racecourse. Overall seroprevalence of infection was detected as 18.50% (89 of 481 horses) by cELISA, with T. equi b...
Wilson AJ, Rambaut A.Horse racing is a multi-million pound industry, in which genetic information is increasingly used to optimize breeding programmes. To maximize the probability of producing a successful offspring, the owner of a mare should mate her with a high-quality stallion. However, stallions with big reputations command higher stud fees and paying these is only a sensible strategy if, (i) there is a genetic variation for success on the racecourse and (ii) stud fees are an honest signal of a stallion's genetic quality. Using data on thoroughbred racehorses, and lifetime earnings from prize money (LE) as a ...
Rogers CW, Gee EK, Firth EC.To obtain initial baseline data on the management of Thoroughbred stud farms in the North Island of New Zealand. Methods: Data on the management of Thoroughbred stud farms were collected from a sample of 22 stud farms located in the south Auckland/Waikato region (n=15) and lower North Island (n=7) of New Zealand, using a face-to-face survey. The studmaster provided information on the size, scope and management of the farms during the 2004/2005 breeding season. Analysis was based on the location of the farm and size of the breeding operation (number of resident mares). Results: Effective farm s...
Lindgren K, Ljungvall O, Nilsson O, Ljungström BL, Lindahl C, Höglund J.Environmental contamination and the egg excretion pattern of the ascarid Parascaris equorum (Nematoda) was investigated in relation to anthelmintic treatment on a Swedish stud farm. Faecal samples from 15 foals, dewormed every 8th-week with a paste formulation of ivermectin at the standard dose rate of 0.2 mg/kg bodyweight, were collected at five sampling occasions between August and November 2006. In addition, soil samples were obtained from four paddocks used by these foals in November 2006. The number of eggs per gram (epg) was counted in both faeces and soil. Egg excretion started when the...
Allen WR, Brown L, Wright M, Wilsher S.Previous surveys of reproductive efficiency in British Thoroughbreds included only mares and stallions standing on studfarms in and around Newmarket. The present study was widened to compare Flatrace (FR) (Group A) and National Hunt (NH) (Group B) mares and stallions on studfarms throughout England. Objective: To assess the influences of mare type, status and age, and veterinary manipulations on reproductive efficiency parameters. To compare the inherent fertility of stallions, based on singleton and twin pregnancy rates and pregnancy loss rates, in Groups A and B Thoroughbred breeding stock. ...
Muscatello G, Leadon DP, Klayt M, Ocampo-Sosa A, Lewis DA, Fogarty U, Buckley T, Gilkerson JR, Meijer WG, Vazquez-Boland JA.Infection with Rhodococcus (Corynebacterium) equi is a well-recognised condition in foals that represents a consistent and serious risk worldwide. The condition manifests itself primarily as one of pulmonary abscessation and bronchitis, hence the terminology of 'rattles' derived from its most obvious clinical sign, frequently terminal when first identified. This review addresses the clinical manifestation, bacteriology and pathogenesis of the condition together with recent developments providing knowledge of the organism in terms of virulence, epidemiology, transmission and immune responses. E...
Slocombe JO, de Gannes RV, Lake MC.The aims of studies in 2002 and 2003 on three farms with 76 foals naturally infected with Parascaris equorum were to (i) identify if the nematode was resistant to ivermectin and moxidectin, and (ii) confirm the effectiveness of fenbendazole and pyrantel pamoate for the parasite. Twelve clinical trials, each with a Fecal Egg Count Reduction Test, were conducted on two Thoroughbred and one Standardbred farms in southwestern Ontario, Canada. In each trial, Parascaris eggs/g feces were estimated for each foal pre- and post-treatment using the Cornell-Wisconsin double flotation and Cornell-McMaster...
Staempfli S, Janett F, Burger D, Kündig H, Imboden I, Hässig M, Thun R.In this study, the effect of exercise (treadmill, riding) on scrotal surface temperature (SST) in the stallion with and without suspensory was evaluated. Experiments were carried out between September and November 2004 using 12 Franches-Montagnes stallions from the National Stud in Avenches (Switzerland). Each stallion performed a standardized incremental treadmill and a ridden test with and without suspensory. The intensity of exercise was monitored by heart rate and blood lactate concentration. For SST measurements, special thermistors were developed and affixed to the most ventral part of t...
Makrai L, Kira K, Kono A, Sasaki Y, Kakuda T, Tsubaki S, Fodor L, Varga J, Taka S.The plasmid profiles of virulent Rhodococcus equi strains isolated on three horse-breeding farms located in different parts of Hungary were investigated. From 49 soil samples collected on the three farms, 490 R. equi isolates (10 from each sample) were obtained and tested for the presence of 15- to 17-kDa antigens (VapA) by immunoblotting and PCR. Ninety-eight VapA-positive isolates were detected from 30 of the 49 culture-positive samples with a prevalence ranging from 13.1% to 23.2%. Of the 98 virulent isolates, 70 contained an 85-kb type I plasmid, 13 contained an 87-kb type I plasmid, and 1...
Vidament M.Results on procedures for freezing stallion semen and the subsequent fertility during 20 years are presented. The present system applied in French National Stud includes: (1) a freezing protocol (dilution in milk, centrifugation and addition of freezing extender (INRA82+egg yolk (2%, v/v)+glycerol (2.5%, v/v) at 22 degrees C, a moderate cooling rate to 4 degrees C and freezing at -60 degrees C/min in 0.5-ml straws); (2) selection of ejaculates showing post-thaw rapid motility >35%; and (3) an insemination protocol (mares examined once daily, two AI of 400 x 10(6) spermatozoa 24 h apart before ...
Wood JL, Kelly L, Cardwell JM, Park AW.The transmission of contagious equine metritis (CEM) on stud farms in Britain, Ireland and other European countries is prevented by following the recommendations in the Horserace Betting Levy Board's Code of Practice on CEM. A quantitative risk assessment was undertaken to estimate the likely impact of removing the recommendation, from the 2002 code, to culture endometrial or cervical swabs microaerophilically for the presence of Taylorella equigenitalis, the causative organism. The scientific literature was reviewed for evidence about the anatomical distribution of T. equigenitalis at differe...
Thompson JA, Love CC, Stich KL, Brinsko SP, Blanchard TL, Varner DD.In equine breeding, the number of spermatozoa ejaculated is considered an important factor in fertility. Methods for predicting the number of spermatozoa have been derived from semen collection procedures. A once-daily collection period for 10 days is a standard recommendation to predict long-term daily sperm output (DSO). The first objective of this study was to determine the precision or repeatability of these DSO predictions. Semen was collected and evaluated daily during four periods for 10 days, for 15 different stallions. The analytical methods utilized hierarchal Bayesian modeling as im...
Cirak VY, Güleğen E, Bauer C.A cross-sectional survey was performed on ten stud farms in western Anatolia, Turkey, in order to provide the first information on the problem of anthelmintic resistance in equine strongyles in this country. Benzimidazole (BZ) resistant cyathostomin populations were detected on seven farms if pre- and post-treatment egg counts are compared in treated animals and the resistance is defined as a mean faecal egg count reduction (FECR) of <95% with a lower 95% confidence limit of <90%. Egg hatch tests using an ED(50) of 0.1 microg/ml thiabendazole as the cut-off value confirmed BZ resistance on fou...
van der Holst W.Season was shown to markedly influence semen characteristics of stallions in Holland, including ejaculate volume, sperm motility, total number of spermatozoa/ejaculate and the percentage of spermatozoa showing morphological abnormalities. Maintenance of normal stallions in continuous light during the winter months and administration of a vitamin and mineral supplement to sub-fertile stallions before the start of the breeding season appeared to improve spermatogenesis significantly.
The Journal of heredityMay 1, 1994
Volume 85, Issue 3 222-224 doi: 10.1093/oxfordjournals.jhered.a111439
Bowling AT.Analysis of selected studbook records of the American Paint Horse Association, consisting of 687 foals sired by 13 overo stallions from non-overo mares, supports the inheritance of overo spotting as an autosomal dominant gene. More than one gene may control patterns registered as overo. Additional studies are necessary to explain the sporadic occurrence of overo spotting from nonspotted quarter horse parents and to confirm the inheritance of overo spotting in other breeds.
Simpson DJ, Greenwood RE, Ricketts SW, Rossdale PD, Sanderson M, Allen WR.In 1981 a trial was conducted on 6 Newmarket Thoroughbred stud farms into the use of real-time ultrasound echography (scanning) as an aid to the early diagnosis of pregnancy in the mare. The procedure was found to be practicable and interpretation of the findings was relatively straightforward. Pregnancy was positively diagnosed from as early as 14 days after ovulation and a number of twin pregnancies were recognized, some in which the conceptuses were situated in separate horns of the uterus but an almost equal number in which the conceptuses were together in the same horn. It was concluded t...
Van Wyk JA, Van Wijk EF.This paper is apparently the first report of resistance of helminths of equids to anthelmintics in South Africa. While a strain of Cyathostominae from an Arab horse stud near Pretoria showed greatly reduced susceptibility to benzimidazoles in faecal egg reduction tests, ivermectin was apparently still unaffected. It is suggested that integrated methods of control such as alternation of horses and ruminants on pasture and mechanical removal of faeces should be used in addition to anthelmintics.
Walbornn SR, Love CC, Blanchard TL, Brinsko SP, Varner DD.Breeding records were analyzed from 24 Thoroughbred stallions that were subjected to dual-hemisphere breeding (DH), including novice (first-year; NOV; n = 11) and experienced (EXP; n = 13) stallions. Fertility variables included seasonal pregnancy rate, pregnancy rate per cycle, and first-cycle pregnancy rate. In addition, values for book size, total number of covers, distribution of mare type (maiden, foaling, and barren) within a stallion's book, cycles per mare, and mare age were examined. Some data were also categorized by mare type (maiden-M, foaling-F, and barren-B). Five separate an...
Baska-Vincze B, Baska F, Szenci O.Monitoring fetal heart rate (FHR) and fetal heart rate variability (FHRV) helps to understand and evaluate normal and pathological conditions in the foal. The aim of this study was to establish normal heart rate reference values for the ongoing equine pregnancy and to perform a heart rate variability (HRV) time-domain analysis in Lipizzaner mares. Seventeen middle- and late-term (days 121-333) pregnant Lipizzaner mares were examined using fetomaternal electrocardiography (ECG). The mean FHR (P = 0.004) and the standard deviation of FHR (P = 0.012) significantly decreased during the pregnancy. ...
Junkkari R, Simojoki H, Heiskanen ML, Pelkonen S, Sankari S, Tulamo RM, Mykkänen A.Newly weaned horses in Finland are often moved to unheated loose housing systems in which the weanlings have free access to a paddock and a shelter. This practice is considered to be good for the development of young horses. The daily temperatures can stay below - 20 °C in Finland for several consecutive weeks during the winter season. However, the effect of unheated housing in a cold climatic environment on the respiratory health of weanlings under field conditions has not been studied before. This investigation was an observational field-study comprising 60 weanlings among 11 different vo...
Bolwell CF, Rosanowski SM, Scott I, Sells PD, Rogers CW.Against a global background of increasing anthelmintic resistance in parasites, little is known about the current parasite control strategies adopted within the equine industry in New Zealand. The aim of the study was to describe and compare the current parasite management and control practices used on Thoroughbred and Standardbred stud farms in New Zealand. An online questionnaire was used to collect data on the demographics of respondents, parasite control methods, grazing management, and use of faecal egg counts. Questions regarding parasite control strategy, how often horses were dewormed,...
Egri B, Sárközy P, Bánhidy G.From 14 to 17 April 1990 and from 12 to 21 May 1993 a total of 136 Caucasian (Donish, Karabakh, Kabardin, local halfbred) and 26 thoroughbred stud-horses were examined for ectoparasites in studs of Stawropol County, Russia. A total of 4054 botfly larvae were identified from 9700 faecal samples collected during a period of 3-4 days after oral treatment with Eqvalan (MSD), Strongid Plus (Pfizer) and Vermitan Plus (Sanofi-Chinoin). The species distribution was: Gasterophilus intestinalis 84.53%, G. nasalis 10.41%, G. haemorrhoidalis 3.62%, G. inermis 1.41%. Gasterophilus nasalis and G. inermis ha...
Hanlon DW, Firth EC.The objective of this study was to investigate the effects of intravaginal progesterone on the reproductive performance of transitional Thoroughbred mares on commercial stud farms. Two hundred twenty-seven (227) non-lactating transitional Thoroughbred mares aged between 4 and 18 y (mean 9.4 ± 3.2 y) located on three stud farms in the Waikato region of New Zealand were used in the study performed during four consecutive breeding seasons (2007-10). Mares were age-matched in pairs and either treated with an intravaginal progesterone releasing device (Cue-Mare, 1.72 g progesterone, 10% w/w) for u...
Rosanowski SM, Bolwell CF, Scott I, Sells PD, Rogers CW.Against a global background of increasing anthelmintic resistance in parasites and a domestic over-reliance on anthelmintics to control gastrointestinal parasites, little is currently known about the resistance status of equine parasites in New Zealand. The objective of the study was to investigate the efficacy of ivermectin in yearling Thoroughbreds. Data were collected from six stud farms from November 2014 to January 2015. Yearlings were selected based on not being treated with anthelmintics for a minimum of six weeks previously and on having a preliminary screening strongyle faecal egg cou...
Flash ML, Wong ASM, Stevenson MA, Gilkerson JR.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...
Palmer E.The use of photoperiod, progestagen, prostaglandin and hCG treatments was investigated to obtain mating of mares at predetermined times. The objectives were: (1) synchronization of oestrus at an early time of the year, (2) simplification of treatment schedules by use of vaginal sponges, and (3) use of several controlled cycles by successive synchronization. The following conclusions were reached. First, after a 16 h photoperiod was applied beginning on 25 November, hormonal synchronization of oestrus and ovulation followed by cyclicity were obtained on 1 February; i.e. 2 months of light are es...
Pessoa V, Ramilo DW, Pereira da Fonseca I, Ferreira MB, Marti E, Tilley P.Insect Bite Hypersensitivity (IBH) is a common cutaneous disease, affecting a large number of horses worldwide. Several studies have identified Culicoides spp. saliva as a clinically relevant allergen source. The prevalence of IBH in Portugal, particularly in Lusitano horses, is still not known. However, the environmental characteristics of the national territory are favorable to the activity of Culicoides, and several species of this genus can be found, namely C. imicola and C. obsoletus/C. scoticus. In this study we characterized the Culicoides population present in Lusitano stud farms with ...
Sharma S, Davies Morel MC, Dhaliwal GS.Decreased reproductive performance due to summer stress is a well known phenomenon in farm livestock. Whether this occurs in the mare and specifically how this might affect postpartum reproductive activity and performance, especially at Foal Heat (FH), is unknown. This study, therefore, aims to investigate this and the factors that might affect postpartum reproductive activity. Reproductive records of 228 Thoroughbred mares (694 mare years) bred in subtropical north-western India were retrospectively analysed. Overt oestrous activity occurred within 21 d postpartum in 92.94% (645/694) of mares...
Thompson K, Taylor J, Mendez D, Chicken C, Carrick J, Durrheim DN.There are almost 9,500 full-time employees in Australia's thoroughbred horse breeding industry. During foaling, they can be exposed to bodily fluids and mucous membranes which may present risks for zoonotic disease. These risks can be mitigated through personal biosecurity strategies. The aim of this study was to identify which personal biosecurity strategies were more or less likely to be adopted by workers. Seventeen participants representing 14 thoroughbred breeding farms and three equine veterinary practices in Australia's largest thoroughbred breeding region trialed up to 16 stakeholder-n...
Staempfli S, Janett F, Burger D, Kündig H, Imboden I, Hässig M, Thun R.In this study, the effect of exercise (treadmill, riding) on scrotal surface temperature (SST) in the stallion with and without suspensory was evaluated. Experiments were carried out between September and November 2004 using 12 Franches-Montagnes stallions from the National Stud in Avenches (Switzerland). Each stallion performed a standardized incremental treadmill and a ridden test with and without suspensory. The intensity of exercise was monitored by heart rate and blood lactate concentration. For SST measurements, special thermistors were developed and affixed to the most ventral part of t...
Bartoš L, Bartošová J, Pluháček J.In a previous study, we suggested that the common practice of transporting a mare for mating and then bringing her back to an environment that also contains males that did not sire the fetus may be a major cause of high percentages of pregnancy disruption in domestic horses. In this study, we tested whether disruption of pregnancies induced by AI occurs as frequently as after mating with a strange stallion away from home and is affected by the same factors in the home social environment. Based on 77 records, the probability of pregnancy disruption after AI depended on the social environment in...
Hollinshead FK, Mehegan MK, Gunn A, Nett T, Bruemmer JE, Hanlon DW.The aim of this project was to test the hypothesis that progesterone concentration 5 days after ovulation did not differ between pregnant and nonpregnant Thoroughbred mares on stud farms located in the Waikato region of New Zealand. A prospective cohort study was performed involving five stud farms in the Waikato region of New Zealand during the 2018 breeding season. A total of 275 mares were enrolled in the study. Mares were served by 34 individual stallions. Blood samples were taken from each mare 5 days after ovulation (D0) and measured for progesterone concentration. Early pregnancy was co...
O'Donohue DD, Smith FH, Strickland KL.A two part survey was carried out in Irish Thoroughbred horses in 1988 and 1989 to establish the incidence and prevalence of developmental skeletal problems, particularly possible manifestations of developmental orthopaedic disease (DOD). Survey One was a retrospective study based on a questionnaire involving the foal crops of 46 stud farms for 3 successive seasons; the 1711 animals initially documented represented 10.46% of Irish foal registrations. The second survey involved repeated monitoring of the 1988 foal crop from birth to 18 months of age on 17 stud farms. The 248 foals initially exa...
Makrai L, Kira K, Kono A, Sasaki Y, Kakuda T, Tsubaki S, Fodor L, Varga J, Taka S.The plasmid profiles of virulent Rhodococcus equi strains isolated on three horse-breeding farms located in different parts of Hungary were investigated. From 49 soil samples collected on the three farms, 490 R. equi isolates (10 from each sample) were obtained and tested for the presence of 15- to 17-kDa antigens (VapA) by immunoblotting and PCR. Ninety-eight VapA-positive isolates were detected from 30 of the 49 culture-positive samples with a prevalence ranging from 13.1% to 23.2%. Of the 98 virulent isolates, 70 contained an 85-kb type I plasmid, 13 contained an 87-kb type I plasmid, and 1...
Allen WR, Mathias S, Lennard SN, Greenwood RE.Rapid enzyme-based immunoassays were used to measure concentrations of oestradiol-17 beta and progesterone in daily blood samples recovered throughout oestrus and for a few days after ovulation from 34 Thoroughbred and 8 pony-type maiden, barren and foaling mares. The first detectable fall in oestradiol-17 beta levels occurred in 88% of the mares within the interval -72 to 0 h with respect to ovulation and in 65% of mares within the interval of -48 to 0 h. The results indicated that serial daily hormone assays of this type could, in a high proportion of animals, predict a correct time for a si...
Olsen HF, Meuwissen T, Klemetsdal G.The aim of this study was to examine how to apply optimal contribution selection (OCS) in the Norwegian and the North-Swedish cold-blooded trotter and give practical recommendations for the future. OCS was implemented using the software Gencont with overlapping generations and selected a few, but young sires, as these turn over the generations faster and thus is less related to the mare candidates. In addition, a number of Swedish sires were selected as they were less related to the selection candidates. We concluded that implementing OCS is feasible to select sires (there is no selection on m...
Gawor JJ.Autopsies and analyses of faecal samples from working horses have shown common occurrence of ascarids in foals, whereas 19.6% of adult horses have been found infected. No influence of season on EPG in adult horses has been found. Study based on faecal samples from stud horses has shown that 5-6-month old animals were most susceptible to the infection. 50% of foals have been found infected in spite of deworming with the use of bezimidazole compounds. It has been stated that the proper dose of an anthelminthic is a basic problem in the control of ascarids.
