Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Horse Breeds
Horse breeds represent the diverse genetic and phenotypic variations found within the species Equus ferus caballus. These breeds are categorized based on characteristics such as size, conformation, coat color, and temperament, which have been selectively bred over centuries to fulfill specific roles and functions. Common classifications of horse breeds include light horses, draft horses, and ponies, each serving different purposes ranging from riding and racing to work and companionship. This page aggregates peer-reviewed research studies and scholarly articles that explore the genetics, history, and functional attributes of various horse breeds, as well as their impact on equine management and breeding practices.
Hepatic lobe torsion in a horse. A 4-year-old Belgian mare was presented with a 1-week history of fever, suspected of being caused by peritonitis. The mare died before the diagnostic procedures had been completed; postmortem examination revealed torsion of the left medial lobe of the liver, resulting in diffuse necrosis of liver tissue and severe peritoneal effusion. Une jument belge de 4 ans est présentée avec une anamnèse de fièvre qui persiste depuis 1 semaine, que l’on soupçonne causée par une péritonite. La jument est morte avant l’achèvement des procédures diagnostiques; l’autopsie a révélé une torsio...
Chronology and sequence of emergence of permanent premolar teeth in the horse: study of deciduous premolar ‘cap’ removal in Thoroughbred racehorses. There are few published data to support the ages of emergence of permanent dentition widely reported in horses. Objective: To clarify the chronology and sequence of permanent premolar (PM) tooth emergence in Thoroughbred racehorses. Methods: A prospective study was undertaken in which records were kept of deciduous PM 'cap' extractions performed during routine dental examinations in Thoroughbred racehorses. Mixed effects multiple regression analysis was used to relate the observed ages, measured in days, for PM 'cap' extractions simultaneously with different predictive variables. Care was take...
Seven novel KIT mutations in horses with white coat colour phenotypes. White coat colour in horses is inherited as a monogenic autosomal dominant trait showing a variable expression of coat depigmentation. Mutations in the KIT gene have previously been shown to cause white coat colour phenotypes in pigs, mice and humans. We recently also demonstrated that four independent mutations in the equine KIT gene are responsible for the dominant white coat colour phenotype in various horse breeds. We have now analysed additional horse families segregating for white coat colour phenotypes and report seven new KIT mutations in independent Thoroughbred, Icelandic Horse, Germ...
Congenital ocular anomalies in purebred and crossbred Rocky and Kentucky Mountain horses. This abstract gives a critique of a research study on ocular anomalies in Rocky and Kentucky Mountain Horses. The author identifies various flaws in the study, arguing that poor sample [...]
Factors influencing conception rates of Arab mares in Tunisia. In order to investigate the factors affecting the reproduction efficiency of Arab breeding mares in Tunisia, breeding data corresponding to 2340 mated cycles, over 5 years (from 2000 to 2004), from 555 mares offspring of 50 sires and bred with 17 stallions were analysed using a multivariate logistic regression. We chose logit link function and binomial distribution and we used log-likelihood-ratio (LL) and Wald tests (X(2)Wald) to test the mean values. The factors of variation included in the model were the year, the stallion, the age of the mare at mating, the sire and the category of the mar...
Coat color variation at the beginning of horse domestication. The transformation of wild animals into domestic ones available for human nutrition was a key prerequisite for modern human societies. However, no other domestic species has had such a substantial impact on the warfare, transportation, and communication capabilities of human societies as the horse. Here, we show that the analysis of ancient DNA targeting nuclear genes responsible for coat coloration allows us to shed light on the timing and place of horse domestication. We conclude that it is unlikely that horse domestication substantially predates the occurrence of coat color variation, which...
The heart and its valves in Caspian miniature horse: a topographic study. The Caspian miniature horse is one of the rare small breeds in the north of Iran. In the present study, the position of the heart and its valves were determined topographically in 4 miniature horses. We found that Caspian miniature horses have general similarities, with certain topographical variability, with other horses.
Exercise during training is associated with racing performance in Thoroughbreds. This study aimed to determine the effects of exercise on racecourse performance in horses racing on the flat. Daily exercise and race records were obtained over a 2-year period for a cohort of racehorses in training for which injury data were also available. Multivariable regression techniques were used to investigate associations between canter, training gallop and race distances accumulated in the 30 days prior to each race and the odds of winning the race, earning prize money and the amount of prize money won. Higher cumulative high-speed (gallop+race) distances were associated with increas...
Change in Morphology of Spermatozoa from Dismount Semen during the Breeding Season in Thoroughbred Stallions in Japan. To clarify the physiological changes of sperm morphology in active Thoroughbred stallions during the breeding season, we examined the dismount semen collected from the penile urethra immediately after service. The spermatozoa were analyzed for relationships between the morphology and the stallion's age or the number of services. Seasonal variation was apparent in the rate of the sperm tail abnormalities, spermatozoa with cytoplasmic droplets, appearance of medusa cells, and sperm head length. Area and width of the sperm head correlated negatively with age (P<0.05). The rate of appearance of...
Breeding value estimation in the Hungarian Sport Horse population. 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...
Association between myeloperoxidase concentration in equine frozen semen and post-thawing parameters. Despite improvement of techniques, semen of 20% of stallions remains unfreezable. Recent studies focused on the impact of reactive oxygen species and oxidant enzymes on semen characteristics. Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutrophils during degranulation or after cell lysis. It is responsible for the formation of hypochlorous acid, a strong oxidant agent, which could damage spermatozoa. The aim of this study was to determine the relation between MPO concentration and characteristics of frozen semen from stallions. Thirty-five straws from different s...
Sire x stud interaction for body measurement traits in Spanish Purebred horses. The mating policy for Spanish Purebred horses encourages the same or closely related stallions to be used for reproduction across studs differing in environments. Stallions may perform differently across studs, and if so, adjustment for the sire x stud (ss) interaction is recommended. However, there are no studies available that analyzed the influence of ss interaction on estimation of genetic parameters in horses. This research is aimed at assessing the implications of including ss interaction in models fitted for the estimation of genetic parameters for traits under selection using 8 body me...
[Characterization of age dependent alterations of the cup of the incisor on the basis of data from Hungarian and German horses]. The authors give a short orientation about the age related parameters of the incisors based on the literature. They examined the question of breed differences with respect to the age determination of horses in the different counties, especially in regard to the English Thoroughbred. In this context they present a new parameter as well as a new approach in data-processing. The cup depth and the yearly abrasion showed high breed-specificity. The relative abrasion indicated that the most intensive wear out is typical for the Thoroughbred. The cup depth and the yearly wear out were different accor...
Intrinsic Factors Influencing the Infection by Helminth Parasites in Horses under an Oceanic Climate Area (NW Spain). A coprological survey to determine the influence of some intrinsic factors (breed, age, and sex) on the infection by helminth parasites in equine livestock (n = 418) under an oceanic climate area (NW Spain) was conducted. Faecal samples were individually collected and analyzed by the coprological techniques. The main strongylid genera identified were Trichonema and Cyalocephalus spp (small strongyles) and Strongylus and Triodontophorus (large strongyles). The prevalence of gastrointestinal nematode was 89% (95% CI 86, 92) and 1% cestoda (0, 2). The percentage of horses with strongyloid parasit...
Characterization of hypertriglyceridemia and response to treatment with insulin in horses, ponies, and donkeys: 44 cases (1995-2005). To characterize signalment, clinical signs of disease, and clinical response to insulin in equids with hypertriglyceridemia. Methods: Retrospective case series. Methods: 20 horses, 17 ponies, and 7 donkeys with hypertriglyceridemia. Methods: For analysis of medical record data, horses, donkeys, and ponies with multiple serum or plasma triglycerides measurements were separated into groups. Hypertriglyceridemic equids that were (HT-I; n = 14) or were not (HT-N; 10) treated with insulin consisted of equids with an initial triglycerides concentration > 44 mg/dL but 500 mg/dL, all of which were...
[Assessment of hereditary defects and dispositions of the horse under animal welfare aspects]. Persons involved in equine breeding, namely veterinarians, horse breeders and breeding association judges, often lack of an apropriate consciousness about the relevance of heritability or supposed heritability of common horses diseases, which might play a distinctive role in the aetiology of numerous of these diseases. Executing animal welfare rights in equine breeding, the major concern should focus on an objective evaluation of pain, suffering and damages caused by different hereditary diseases. The basis of assessment for hygienic breeding has to be defi ned according to the actual animal w...
Konik and Hucul horses: a comparative study of exterior measurements. An exterior comparison was made between 2 primitive horse breeds: the Konik and the Hucul breeds. Each animal was characterized using 25 measurements and 24 indices. Statistical methods employed in this study were principal components analysis and the Student's t-test. It was found that in spite of both breeds being included in the group of horses with a primitive exterior, the Konik and the Hucul possess completely different metric properties of their body conformations. Although the mean height for the Hucul breed slightly exceeds that of the Konik, the latter has longer scapulae and metacar...
Expression of toll-like receptor 2 mRNA in bronchial epithelial cells is not induced in RAO-affected horses. Airway inflammation in recurrent airway obstruction (RAO) is triggered by housing affected horses in stables.It has been suggested that RAO is an allergic condition, but innate immune mechanisms are also involved. Fungal products activate innate immune mechanisms through toll-like receptor 2 (TLR2). In human airway epithelium, TLR2 activation leads to interleukin (IL)-8 production. This pathway is negatively regulated by the zinc finger protein A20. This study was performed to enhance understanding of innate immune mechanisms in RAO. Objective: TLR2 and IL-8 mRNA are elevated in RAO during sta...
Prevalence of various radiographic manifestations of osteochondrosis and their correlations between and within joints in Dutch warmblood horses. Osteochondrosis (OC) is the most important orthopaedic developmental disorder in horses and may manifest in several different forms. No detailed study on the prevalence and/or interrelation of these forms is available, even though these data are a prerequisite for conclusive genetic studies. Objective: To assess the prevalence of the various manifestations of OC as detected radiographically and to evaluate possible relationships between their occurrence within the same joint and between different joints. Methods: The FP (femoropatellar), TC (tarsocrural) and MCP/MTP (metacarpophalangeal/metata...
Comparison of density gradient and single layer centrifugation of stallion spermatozoa: yield, motility and survival. A new, simpler, technique of colloidal centrifugation has recently been developed, designated single layer centrifugation (SLC). This technique requires evaluation by comparison with a density gradient for its ability to select the best quality spermatozoa and its practicality of use on studfarms. Objective: To compare the effect of 2 methods of colloidal centrifugation, density gradient centrifugation and single layer centrifugation, on stallion sperm motility, yield and survival, using freshly collected extended stallion semen. Methods: Aliquots of extended stallion semen from 10 stallions (...
Refinement of a quantitative trait locus on equine chromosome 5 responsible for fetlock osteochondrosis in Hanoverian warmblood horses. In this report, we provide 29 new informative microsatellites distributed over a region of 21 Mb on horse chromosome (ECA) 5 and refine a quantitative trait locus (QTL) for fetlock osteochondrosis dissecans (OCD) to a genome-wide significant interval between 78.03 and 90.23 Mb on ECA5. Genotyping was performed in 211 Hanoverian warmblood horses from 14 paternal half-sib groups. Within this OCD-QTL, collagen type XXIV alpha 1 was identified as a potential functional candidate gene for equine osteochondrosis. This report is a further step towards unravelling the genes that cause equine osteochon...
The candidate gene XIRP2 at a quantitative gene locus on equine chromosome 18 associated with osteochondrosis in fetlock and hock joints of South German Coldblood horses. A whole-genome scan for radiological signs of osteochondrosis (OC) and osteochondrosis dissecans (OCD) in South German Coldblood (SGC) horses using 250 microsatellite markers identified a genome-wide significant quantitative trait locus (QTL) for fetlock OCD and a chromosome-wide QTL for hock OC on Equus caballus chromosome (ECA) 18 at a relative position of 45.9-78.2 cM. The aim of this study was to analyze associations of single-nucleotide polymorphisms (SNPs) in candidate genes for OC in this QTL region using 96 SGC horses. The OC-QTL on ECA18 could be confirmed and narrowed down to an inte...
Establishment and characterization of a fibroblast cell line from the Mongolian horse. A fibroblast line was successfully established from Mongolian horse ear marginal tissue by using a primary explant technique and cell cryogenic preservation technology. Biological analysis showed the following: The cells were adherent and exhibited density-dependent inhibition of proliferation; assays of microbial contamination from bacteria, fungi, and mycoplasma were negative; the population doubling time of the cells was 33.9 h; and a 2n chromosome number of 64 at a frequency higher than 80%. A lack of cross-contamination of this cell line with other species was confirmed by isoenzyme analy...
A multifrequency HYSCORE study of weakly coupled nuclei in frozen solutions of high-spin aquometmyoglobin. In this work, we show the extreme power of multifrequency HYSCORE (hyperfine sublevel correlation spectroscopy) techniques to unravel the hyperfine interactions of the electron spin with the remote nuclei in the heme site of high-spin ferric heme proteins. Horse heart aquo-metmyoglobin was used as a model system to demonstrate the power of these techniques. Experimental evidence was collected and assigned to protons of the proximal histidine ligand, to the mesoprotons of the heme ligand, and to two different protons of the distal water ligand. The latter difference relates to the stabilization...
Genetic variables of various manifestations of osteochondrosis and their correlations between and within joints in Dutch warmblood horses. Osteochondrosis (OC) is an important orthopedic developmental disorder in many horse populations. A review of the literature revealed widely variable heritability estimates for the disorder. We estimated the genetic variables (heritabilities and genetic correlations) of various manifestations of OC. Femoropatellar, tarsocrural, and metacarpophalangeal and metatarsophalangeal joints of 811 randomly selected yearlings from the Royal Warmblood Studbook of The Netherlands, descending from 32 representative stallions, were scored for OC at 28 predilection sites. At each site, OC was scored in 5 cat...
Hyperactivation of stallion sperm is required for successful in vitro fertilization of equine oocytes. Capacitation is a complex and not well-understood process that encompasses all the molecular changes sperm must undergo to successfully fertilize an oocyte. In vitro fertilization has remained elusive in the horse, as evidenced by low in vitro fertilization (IVF) rates (0%-33%); moreover, only two foals have ever been produced using IVF. Incubation of stallion sperm in modified Whittens supplemented with bovine serum albumin and sodium bicarbonate yielded significant rates of time-dependent protein tyrosine phosphorylation and induced acrosomal exocytosis, consistent with capacitation. The obj...
Colloidal centrifugation with Androcoll-E prolongs stallion sperm motility, viability and chromatin integrity. The objective was to investigate the changes in stallion sperm quality (sperm motility, viability, membrane integrity and chromatin integrity) occurring during cool storage, and to study the effect of sperm selection by single layer colloidal centrifugation on these parameters of sperm quality. Spermatozoa from 3 stallions (10 ejaculates, 3-4 per stallion) were selected by centrifugation through a single layer of colloid (SLC). The resulting sperm preparations and the control samples (extended but unselected semen samples) were stored at 5 degrees C for 48h. Assessments of sperm quality, such ...
Days lost from training by two- and three-year-old Thoroughbred horses: a survey of seven UK training yards. The first major epidemiological study of injury incidence in the UK flat racing Thoroughbred (TB), published in 1985, found lameness to be the single largest reason for days when horses failed to train. It was considered advisable to ascertain if progress has been made in reducing the problem of musculoskeletal injuries in the intervening period. Objective: To quantify injury incidence and days lost from training by 2- and 3-year-old TBs in UK training yards during 2002 and 2003. Methods: One-hundred-and-eighty-two yearling TBs were recruited at the end of 2001 and daily training and injury re...
