Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Genetics
Genetics in horses encompasses the study of hereditary traits and the genetic makeup that influences various characteristics and health conditions in equine populations. This field involves the analysis of genes and their functions, inheritance patterns, and the impact of genetic variations on traits such as coat color, performance ability, and susceptibility to diseases. Research in equine genetics employs techniques such as genome mapping, sequencing, and genetic testing to identify specific genes and mutations associated with these traits. This page gathers peer-reviewed research studies and scholarly articles that explore the genetic basis of equine traits, the methodologies used in genetic research, and the implications for breeding, health management, and conservation of horse breeds.
Amino acid sequence of horse colipase B. The complete sequence of the 96 residues composing horse colipase B has been determined by automated analysis of the intact protein, of two CNBr peptides and two tryptic peptides arising, respectively, from the citraconylated chain and from the unreduced protein. The single histidine of the protein is located at position 29 as in horse colipase A. His86, present in the C-terminal region of the pig cofactor and supposed to play a role in the folding molecule, is not conserved in horse B. Large pieces of the pig and horse B chains were found to be identical or very similar, especially the N-term...
Nucleic acid-protein interactions. Degradation of double-stranded RNA by glycosylated ribonucleases. 1. Extensively glycosylated ribonucleases, like the enzymes from pig and horse pancreas, show a much higher activity on double-stranded RNAs than similarly charged, carbohydrate-free RNAases under stranded assay conditions (relatively high salt concentrations). Glycosylated pig and horse pancreas RNAases also show a larger destabilizing effect on double-stranded poly[d(A-T)] X poly[d(A-T)], than that displayed by bovine RNAase A under these conditions. Both activities show a similar dependence on the ionic strength of the medium. 2. A partial enzymic removal of the heterosaccharide side chains...
Effect of excessive exposure to sodium fluoride on composition and crystallinity of equine bone tumors. Sodium fluoride (5 mg/kg of body weight) was fed for 20 months to horses with hereditary multiple exostoses (HME), a skeletal disorder that primarily affects endochondral bones during skeletal development. Rib biopsies were performed on both HME horses not fed fluoride (control) and HME horses that were fed fluoride to obtain comparable specimens for chemical analyses and x-ray diffraction. Fluoride content of the rib from a horse fed fluoride for 20 months was approximately 20 to 30 times higher than that from a control horse. Fluoride content of the bone tumors was higher than those of norma...
[Evaluation of variability of duration of pregnancy in mares]. In a set of mares of English Thoroughbred horse of the Napajedla stock the gravidity length in the time period from 1880 to 1972 was evaluated. The variability of the gravidity length was evaluated in sets which were put together by combination of two age groups with a division of the studied time period into ten-year stages. Variance and sample means of the gravidity lengths in these sub-groups are significantly different in the period under study. In order to eliminate the action of non-genetic influences qualifying the variability of the gravidity length, and to increase the objectivity of ...
Isolation of cellulolytic phycomycete fungi from the caecum of the horse. Microscopic examination of horse caecum contents revealed vegetative growth of phycomycete fungi on particles of digesta, and uniflagellated cells similar to fungal zoospores in the liquid phase. Three morphologically distinct isolates of strictly anaerobic phycomycete fungi were obtained from the caecum contents and cultured in vitro. Two of the isolates were able to utilize a wide range of plant carbohydrates for growth, including alpha-cellulose, xylan and particulate starch, and extensively digested water-insoluble plant tissues.
Two equine true hermaphrodites with 64,XX/64,XY and 63,XO/64,XY chimerism. The karyotypes of a Welsh pony and a Standardbred were 64,XX/64,XY and 63,XO/64,XY respectively. Both intersexes were true hermaphrodites with bilateral ovotestes. Neither intersex showed stallion-like behaviour. Each one had an underdeveloped penis, bilateral seminal vesicles and uterine tissue. It would appear that the chimerism in these equine intersexes resulted from double fertilization or fusion of blastocysts. Mosaicism in the Standardbred is a possibility, resulting from loss of a Y chromosome by anaphase lag in an early embryonic XY cell.
Major histocompatibility locus in the Arabian horse. Combined immunodeficiency disease (CID) is a genetic disorder of T and B lymphocyte production which results in a nonfunctional immune system. It is inherited as an autosomal recessive trait and has been reported in humans and in horses of the Arabian breed. Arabian horses known to have the CID gene and horses of unknown carrier status were tested using a microlymphocytotoxicity technique. Computer chi 2 analysis distinguished six serologically defined specificities. The study of unrelated horses and a limited number of families showed that the specificities behave as codominant alleles segreg...
An evaluation of contribution derived from investigations of equine immunodeficiencies. Following the descriptions of immunodeficiencies in horses beginning in 1973, there has been considerable effort to develop methods for differential diagnosis and to determine the cause and prevalence of the disorders. In addition, the equine immunodeficiencies, especially combined immunodeficiency, have been studied from a comparative viewpoint with the goal of finding information applicable to similar diseases of children. Coincident with the development of knowledge about the immunodeficiencies per se, considerable information about several aspects of immunology has been obtained. It is the...
Perspectives in perissodactyls. The world-wide foaling rate in the mare is low and in the Hannoverian breed has remained asymptotic at about 50 per cent for over 150 years. In an attempt to discover some of the possible reasons for this low fertility rate, the evolutionary history of the perissodactyls, the odd-toed ungulates, is reviewed here. Of the 156 genera of this order, 152 are in the fossil record; this gives them the highest extermination rate of all the mammal groups. Some of the unusual and unique features of the reproductive physiology of the mare and their possible association with low fertility are considered.
Stabilization of the C-terminal part of pig and horse colipase by carboxypeptidase and trypsin inhibitors. Pig and horse colipases have been purified by a common procedure using trypsin and carboxypeptidase inhibitors as stabilizers. Two forms of pig colipase were identified: a predominant A1 form with about 103-105 residues, and a minor slightly degraded A2 form in which the last two C-terminal residues, Asp and Ser, were lacking. This type of degradation is considerably slowed down by carboxypeptidase inhibitors. A total of four forms of the horse cofactor were characterized: two (A1 and B1) were probably isocolipases which differed by only a few substitutions. Both contained the same number of r...
A cytogenetical study of prenatal loss in the mare. The objective of this study was to investigate an hypothesis that chromosome anomalies are an important cause of prenatal loss in the mare. An attempt was made to analyse, cytogenetically, a series of 26 equine abortuses. Cell cultures were prepared from a range of tissues, but failed to grow, and chromosome analysis was therefore not possible for any of these specimens. Consequently, a study was made of the metaphase chromosomes prepared from 22 equine embryos after their surgical removal from mares' uteri. The karyotypes prepared for each specimen were normal. The current findings are discus...
[An analysis of stallion fertility based on the number of matings per heat]. The fertility problems were studied in the herd of the English Thoroughbred horse on the Napajedla stud farm. Breeding records for the period from 1880 to 1972 were used as the starting data. The survey comprised 32 stallions. The relationship between fertility and the number of matings was calculated by the chi 2 quantity. The calculated values are highly variable. However, it is generally seen in most of the stallions that the number of matings per heat (i. e. one or several matings) had no significant influence on the pregnancy of mares and on the fertility values of the stallions. A higher...
Studies on the chromosomes and sex chromatin in the horse. This study provides accumulated data to assist the definition of karyotypes from normal and infertile horses. The normal karyotype of the horse (2n = 64) was characterized following Giemsa staining and C- banding, and 23% aneuploidy was found among chromosome counts of cells prepared from 44 clinically normal horses and 24 equine embryos. These expected variations in chromosome counts are especially important in the evaluation of potential mosaicism. Centromere staining was shown to be a valuable aid for the identification of specific chromosomes, in particular the sex chromosomes. Sex chromat...
Central nervous system demyelination in Venezuelan equine encephalomyelitis infection. Arboviruses are important pathogens for both animals and humans. Venezuelan equine encephalomyelitis virus (VEEV) is an arbovirus whose pathogenicity for grey matter structures has been previously studied. To our knowledge, the present study is the first to describe extensive inflammation and demyelination in spinal cord white matter of mice infected with VEEV. To probe a possible immunepathogenesis of white matter alterations in this infection, nude mice and heterozygous controls were similarly infected. Whereas controls still showed inflammatory demyelination, nude mice showed no white matte...
Activation of pigeon erythrocyte adenylate cyclase by cholera toxin. Partial purification of an essential macromolecular factor from horse erythrocyte cytosol. A cytosolic, macromolecular factor required for the cholera toxin-dependent activation of pigeon erythrocyte adenylate cyclase and cholera toxin-dependent ADP-ribosylation of a membrane-bound 43,000 dalton polypeptide has been purified 1100-fold from horse erythrocyte cytosol using organic solvent precipitation and heat treatment. This factor, 13,000 daltons, does not absorb to anionic or cationic exchange resins, is sensitive to trypsin or 10% trichloroacetic acid and is not extractable by diethyl ether. Activation of adenylate cyclase by cholera toxin requires the simultaneous presence of AT...
