Topic:Equids
Equids are members of the family Equidae, which includes modern horses, donkeys, and zebras, as well as extinct species. Equids are characterized by their long limbs, single-toed hooves, and herbivorous diet, which is primarily composed of grasses. Horses, specifically, have been domesticated for thousands of years and have played significant roles in agriculture, transportation, and sport. This page compiles peer-reviewed research studies and scholarly articles that explore various aspects of equids and horses, including their evolution, physiology, behavior, and interactions with humans. The collected works provide insights into the genetic diversity, adaptive traits, and conservation efforts related to equid species.
Patterning and post-patterning modes of evolutionary digit loss in mammals. A reduction in the number of digits has evolved many times in tetrapods, particularly in cursorial mammals that travel over deserts and plains, yet the underlying developmental mechanisms have remained elusive. Here we show that digit loss can occur both during early limb patterning and at later post-patterning stages of chondrogenesis. In the 'odd-toed' jerboa (Dipus sagitta) and horse and the 'even-toed' camel, extensive cell death sculpts the tissue around the remaining toes. In contrast, digit loss in the pig is orchestrated by earlier limb patterning mechanisms including downregulation of...
Spatial characterization of Leptospira spp. infection in equids from the Brejo Paraibano micro-region in Brazil. The present study, the first to spatially characterize Leptospira spp. infection among equids in the Brejo Paraibano micro-region of the Paraiba state in the northeast of Brazil, investigated 257 animals in 26 farms properties. Serum samples from 204 horses, 46 mules and seven donkeys were serologically diagnosed using the microscopic agglutination test (MAT). The distribution of Leptospira spp. was studied by employing specific antigens from 24 different Leptospira serovars. All farms were georeferenced and their distribution visualised on a map of the Brejo Paraibano micro-region. In additio...
Analysis of horse genomes provides insight into the diversification and adaptive evolution of karyotype. Karyotypic diversification is more prominent in Equus species than in other mammals. Here, using next generation sequencing technology, we generated and de novo assembled quality genomes sequences for a male wild horse (Przewalski's horse) and a male domestic horse (Mongolian horse), with about 93-fold and 91-fold coverage, respectively. Portion of Y chromosome from wild horse assemblies (3 M bp) and Mongolian horse (2 M bp) were also sequenced and de novo assembled. We confirmed a Robertsonian translocation event through the wild horse's chromosomes 23 and 24, which contained sequences th...
Use of a motorized morcellator for elective bilateral laparoscopic ovariectomy in standing equids: 30 cases (2007-2013). To describe the use of a motorized morcellator for elective bilateral laparoscopic ovariectomy in standing equids and to evaluate long-term outcome. Methods: Retrospective case series. Methods: 30 equids (20 horses, 9 mules, and 1 pony). Methods: Medical records of equids undergoing elective bilateral laparoscopic ovariectomy from 2007 to 2013 were evaluated. Cases were selected on the basis of use of a motorized morcellator for ovary extraction. Data collected included age, breed, reason for surgery, surgery date, surgical approach, intraoperative complications, surgery and morcellation times...
Secretoglobin 1A1 and 1A1A differentially regulate neutrophil reactive oxygen species production, phagocytosis and extracellular trap formation. Secretoglobin family 1A member 1 (SCGB 1A1) is a small protein mainly secreted by mucosal epithelial cells of the lungs and uterus. SCGB 1A1, also known as club (Clara) cell secretory protein, represents a major constituent of airway surface fluid. The protein has anti-inflammatory properties, and its concentration is reduced in equine recurrent airway obstruction (RAO) and human asthma. RAO is characterized by reversible airway obstruction, bronchoconstriction and neutrophilic inflammation. Direct effects of SCGB 1A1 on neutrophil functions are unknown. We have recently identified that the SC...
Equid herpesvirus type 4 uses a restricted set of equine major histocompatibility complex class I proteins as entry receptors. Equid herpesvirus type 1 (EHV-1) was shown to use an unusual receptor for cellular entry - MHC-I molecules. Here, we demonstrated that the closely related EHV, EHV-4, also uses this strategy for cellular invasion, both in equine cells in culture and in the heterologous, non-permissive murine mastocytoma cell line (P815) after stable transfection with horse MHC-I genes. Using a panel of P815 cell lines transfected with individual horse MHC-I genes, we provided support for the hypothesis that EHV-1 and EHV-4 target classical polymorphic MHC-I molecules as viral entry receptors. All known equine ...
Can equids be a reservoir of Leishmania braziliensis in endemic areas? In this study, we detected Leishmania (Viannia) braziliensis infection in equids living in endemic regions of cutaneous leishmaniasis. To determine the role of these animals in the Leishmania cycle, we used two approaches: serological and molecular methods. Antibodies to the parasite were assayed using the Enzyme Linked Immunosorbent Assay (ELISA). Blood samples were collected and tested by polymerase chain reaction (PCR), and the positive products were sequenced. The results showed that 11.0% (25/227) of the equids were seropositive for Leishmania sp, and 16.3% (37/227) were PCR positive. Ant...
Estimation of body weight and development of a body weight score for adult equids using morphometric measurements. Excessive BW has become a major health issue in the equine (Equus caballus) industry. The objectives were to determine if the addition of neck circumference and height improved existing BW estimation equations, to develop an equation for estimation of ideal BW, and to develop a method for assessing the likelihood of being overweight in adult equids. Six hundred and twenty-nine adult horses and ponies who met the following criteria were measured and weighed at 2 horse shows in September 2011 in Minnesota: age ≥ 3 yr, height ≥ 112 cm, and nonpregnant. Personnel assessed BCS on a scale of 1 t...
Complications associated with perineal urethrotomy in 27 equids. To report the clinical findings, incidence of complications, and outcome associated with perineal urethrotomy in equids. Methods: Retrospective case series. Methods: Equids (n = 27). Methods: Medical records (January 2000 to December 2010) of equids that had a perineal urethrotomy were reviewed. Data retrieved and evaluated were breed, age, surgical technique, use of general anesthesia, complications, time from surgery to development of complications and their management, and outcome. Results: Perineal urethrotomy was performed for urolithiasis (n = 22), for treatment of urethral rents...
Occlusal enamel complexity in middle miocene to holocene equids (Equidae: Perissodactyla) of North America. Four groups of equids, "Anchitheriinae," Merychippine-grade Equinae, Hipparionini, and Equini, coexisted in the middle Miocene, but only the Equini remains after 16 Myr of evolution and extinction. Each group is distinct in its occlusal enamel pattern. These patterns have been compared qualitatively but rarely quantitatively. The processes influencing the evolution of these occlusal patterns have not been thoroughly investigated with respect to phylogeny, tooth position, and climate through geologic time. We investigated Occlusal Enamel Index, a quantitative method for the analysis of the comp...
Seroprevalence of Babesia caballi and Theileria equi in five draught equine populated metropolises of Punjab, Pakistan. Equine piroplasmosis (EP) caused by intraerythrocytic parasites (Theileria equi and Babesia caballi) is an emerging equine disease of world-wide distribution. In Pakistan, the prevalence and incidence of EP are unknown. In order to obtain the first insights into the prevalence of the disease, a total of 430 equids, including 33 mules, 65 horses and 332 donkeys, aging from ≤ 5 to ≥ 10 years of either sex, from five metropolises of Punjab, Pakistan, were serologically tested for the presence of antibodies directed against B. caballi and T. equi, using a competitive enzyme-linked immunosorben...
Prevalence of cutaneous pathological conditions and factors associated with the presence of skin wounds in working equids in tropical regions of Veracruz, Mexico. A wide spectrum of welfare issues is encountered on working equids. The objectives of this study were: (i) to determine the prevalence of cutaneous lesions in working equids in tropical regions of the North-Central of Veracruz State, Mexico, (ii) to identify the most prevalent cutaneous pathological conditions in this population of working equids, and (iii) to identify risk factors associated to the presence of work-related skin wounds. A number of 467 working equids presented for treatment at Donkey Sanctuary Mobile Clinic Program - National Autonomous University of Mexico from seven differen...
Standing equine dental surgery. Dental surgeries refer to procedures that affect the dental tissues or their supporting structures. With the development of specific, efficacious, and conservative treatments, morbidity risks have been lowered and chances of benefiting the health of equids improved. Advances in quality of sedation, analgesia, and locoregional anesthesia allow a majority of dental surgeries to be performed in the standing patient. This update focuses on an orthograde endodontic technique, a minimally invasive buccotomy technique, with the potential to combine it with a transbuccal screw extraction technique, an...
Equine adipose-derived stem cell (ASC) expresses BAFF and its receptors, which may be associated with the differentiation process of ASC towards adipocyte. B cell activating factor (BAFF) and its receptors were regarded as elements of the immune system, regulating the fate of B cell. In recent years, these molecules were identified in a number of normal and pathological tissues, expanding their potential functions beyond the immune system. In this study, on the basis of molecular clone and prokaryotic expression of equine BAFF, we reported that equine adipose-derived stem cell (ASC) expressed BAFF and its receptors, which exhibited the increased expression during ASC adipogenic differentiation in vitro. Moreover, with the addition of recombinant ...
A genome wide study of genetic adaptation to high altitude in feral Andean Horses of the páramo. Life at high altitude results in physiological and metabolic challenges that put strong evolutionary pressure on performance due to oxidative stress, UV radiation and other factors dependent on the natural history of the species. To look for genes involved in altitude adaptation in a large herbivore, this study explored genome differentiation between a feral population of Andean horses introduced by the Spanish in the 1500s to the high Andes and their Iberian breed relatives. Results: Using allelic genetic models and Fst analyses of ~50 K single nucleotide polymorphisms (SNPs) across the horse...
Body mass evolution and diversification within horses (family Equidae). Horses (family Equidae) are a classic example of adaptive radiation, exhibiting a nearly 60-fold increase in maximum body mass and a peak taxonomic diversity of nearly 100 species across four continents. Such patterns are commonly attributed to niche competition, in which increased taxonomic diversity drives increased size disparity. However, neutral processes, such as macroevolutionary 'diffusion', can produce similar increases in disparity without increased diversity. Using a comprehensive database of Equidae species size estimates and a common mathematical framework, we measure the contribu...
Horses (Equus caballus) discriminate body odour cues from conspecifics. Knowledge about social recognition and memory in animals can help us to determine appropriate management and husbandry techniques. In this study, we used a habituation-discrimination procedure to investigate the ability of horses (Equus caballus) to distinguish between the body odour samples of unfamiliar conspecifics. To pick up body odour, we rubbed material on the coat of horses and presented these unknown body odours to 16 different conspecifics of the same sex and similar age. The test consisted of two successive two-min presentations of a sample from one individual (e.g. individual 'A') ...
Motion camouflage induced by zebra stripes. The functional significance of the zebra coat stripe pattern is one of the oldest questions in evolutionary biology, having troubled scientists ever since Charles Darwin and Alfred Russel Wallace first disagreed on the subject. While different theories have been put forward to address this question, the idea that the stripes act to confuse or 'dazzle' observers remains one of the most plausible. However, the specific mechanisms by which this may operate have not been investigated in detail. In this paper, we investigate how motion of the zebra's high contrast stripes creates visual effects tha...
The brain of the horse: weight and cephalization quotients. The horse is a common domestic animal whose anatomy has been studied since the XVI century. However, a modern neuroanatomy of this species does not exist and most of the data utilized in textbooks and reviews derive from single specimens or relatively old literature. Here, we report information on the brain of Equus caballus obtained by sampling 131 horses, including brain weight (as a whole and subdivided into its constituents), encephalization quotient (EQ), and cerebellar quotient (CQ), and comparisons with what is known about other relevant species. The mean weight of the fresh brains in o...
A clinical survey on the prevalence and types of cheek teeth disorders present in 400 Zamorano-Leonés and 400 Mirandês donkeys (Equus asinus). Dental disease is now recognised as a major but often unrecognised disorder of equids, including horses and donkeys. However, very few large clinical studies have documented the prevalence and type of dental disease present in different equid populations and no dental studies have been reported in Zamorano-Leonés or Mirandês donkeys, two endangered donkey breeds. Clinical and detailed oral examinations were performed in 400 Mirandês and 400 Zamorano-Leonés donkeys in Portugal and Spain. It was found that just 4.5 per cent had ever received any previous dental care. Cheek teeth (CT) disorde...
The role of the 3′ region of mammalian gonadotropin β subunit gene in the luteinizing hormone to chorionic gonadotropin evolution. CGβ subunits comprise a unique carboxyl-terminal peptide (CTP) that has multiple O-linked glycans and extends serum half-life of the protein. It has evolved by incorporating a previously untranslated region of the LHβ gene into the reading frame. Although CTP-like sequences are encrypted in the LHβ genes of several mammals, the CGβ subunit developed only in primates and equids. To study this restriction in evolution, we examined whether the cryptic CTP decoded from the bovine LHβ gene (boCTP) possesses key characteristics of the human (h) CGβ-CTP. The boCTP does not impede several crucia...
Identification of equine influenza virus infection in Asian wild horses (Equus przewalskii). An outbreak of equine influenza was observed in the Asian wild horse population in Xinjiang Province, China, in 2007. Nasal swabs were collected from wild horses and inoculated into 9-10-day SPF embryonated eggs. The complete genome of the isolate was sequenced. A comparison of the amino acid sequence revealed that the isolate was an equine influenza virus strain, which we named A/equine/Xinjiang/4/2007. Each gene of the virus was found to have greater than 99 % homology to equine influenza virus strains of the Florida-2 sublineage, which were circulating simultaneously in China, and a lesser ...
Ancient trade routes shaped the genetic structure of horses in eastern Eurasia. Animal exchange networks have been shown to play an important role in determining gene flow among domestic animal populations. The Silk Road is one of the oldest continuous exchange networks in human history, yet its effectiveness in facilitating animal exchange across large geographical distances and topographically challenging landscapes has never been explicitly studied. Horses are known to have been traded along the Silk Roads; however, extensive movement of horses in connection with other human activities may have obscured the genetic signature of the Silk Roads. To investigate the role o...
Helping working Equidae and their owners in developing countries: monitoring and evaluation of evidence-based interventions. There are an estimated 112 million Equidae (horses, donkeys, mules) in the developing world, providing essential resources for their owners' livelihoods and well-being. The impoverished situation of their owners and the often harsh conditions in which they work mean that the animals' welfare is a cause for concern. A number of equine non-governmental organisations (NGOs) operate within working equid communities providing veterinary care, education and training programmes aimed at improving equine welfare. However, there is little published information available that describes monitoring and ev...
The past, present and future of domestic equines in Tanzania. Equines are minor species in Tanzania's array of domestic livestock. Attempts to use them for transport by early explorers from the mid-nineteenth century usually failed. Donkeys were used extensively as pack animals to complement human porters by both British and German forces in the First World War, but their advantages were often outweighed by slow progress and competition with troops and porters for water, and they died in huge numbers. The British had regular cavalry troops in their campaign and mules found limited use as individual mounts for officers. In modern times, there are very few...
A free-ranging, feral mare equus caballus affords similar maternal care to her genetic and adopted offspring. Adoption of nongenetic offspring occurs in a variety of species but is rare in equids. We report a case of adoption by a free-ranging, feral mare Equus caballus and compare the maternal care received by her genetic offspring (born 1995) to that of her adopted offspring (born 1996) for the first 30 weeks of development. We compare five measures of care: (1) total time spent suckling, (2) mare aggression during suckling, (3) number of mare-terminated suckling bouts, (4) contact maintenance, and (5) mare-foal distance. For most behaviors, we detected no difference in the mare's treatment of the t...
West Nile virus surveillance, Brazil, 2008-2010. West Nile virus (WNV) is an emergent pathogen that is widely distributed in North and Central America. The recent introduction in South America has focused attention on the spread of WNV across Southern American countries. The transmission network involves mosquitoes, birds, horses and humans. Methods: The serological evaluation of sera from 678 equids and 478 birds was performed using a WNV-specific blocking ELISA, and only the positive results were confirmed by plaque reduction neutralisation tests (PRNTs). Molecular analysis was performed on sera from 992 healthy equids and on 63 macerates ...
West Nile viral infection of equids. West Nile virus (WNV) is a flavivirus transmitted between certain species of birds and mosquito vectors. Tangential infections of equids and subsequent equine epizootics have occurred historically. Although the attack rate has been estimated to be below 10%, mortality rates can approach 50% in horses that present clinical disease. Symptoms are most commonly presenting in the form of encephalitis with ataxia as well as limb weakness, recumbency and muscle fasciculation. The most effective strategy for prevention of equine disease is proper vaccination with one of the numerous commercially avail...