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.
Evaluation of adenosine deaminase and other purine salvage pathway enzymes in horses with combined immunodeficiency. Foals with combined immunodeficiency had normal levels of purine salvage pathway enzymes, including adenosine deaminase, nucleoside phosphorylase, and xanthine oxidase.
Isolation and some molecular parameters of elastase-like normal proteinases from horse blood leucocytes. Cytoplasmic granules were isolated from horse blood polymorphonuclear leucocytes by the heparin method and extracted with 0.9% NaCl by repeated freezing. Soluble proteins were separated on a column of Sephadex G-75 followed by chromatography on a column of CM-Sephadex with a NaCl gradient. Gel filtration, density-gradient centrifugation, isoelectric focusing and 0.1% sodium dodecyl sulphate/polyacrylamide-gel electrophoresis at pH 7.0 and at pH 4.5 were used to determine molecular parameters of proteinases. Three enzymes hydrolysing both casein and N-benzyloxycarbonyl-L-alanine nitrophenyl est...
The pregnancy protecting effect of progesterone against human chorionic gonadotrophin challenge in mares. 14 pregnant Welsh Mountain Pony mares were treated with progesterone in an effort to prevent pregnancy failure induced by administration of human chorionic gonadotropin (GCG). 13 of the 14 mares were treated with progesterone by injection or implant before the 38th day of pregnancy. HCG was given in 3 doses on alternate days at a dose rate of 2000 imc/day. The remaining mare was treated with HCG toward the end of the experiments to demonstrate the abortifacient property of HCG. 3 mares aborted and 1 of these was anovulatory thereafter. Further research is needed to determine the effective prog...
Concentration of prostaglandins F in uterine venous plasma of anesthetized mares during the estrous cycle and early pregnancy. Prostaglandins F were quantitated by radioimmunoassay in uterine venous plasma of anesthetized mares on day 7 of estrus, days 2, 6, 10, 14 or 18 of diestrus and days 10, 14 or 18 of pregnancy. The PGF concentration was greater (P less than .01) at day 14 of diestrus than at all other days studied. The concentrations at days 10 and 18 of diestrus and at days 10, 14 and 18 of pregnancy were greater (P less than .05) than at day 7 of estrus and days 2 and 6 of diestrus. PGF concentrations at days 10 and 14 were greater (P less than .01) for diestrous than for pregnant mares.
Primary structure determination of two cytochromes c2: close similarity to functionally unrelated mitochondrial cytochrome C. The amino-acid sequences of the cytochromes c2 from the photosynthetic non-sulfur purple bacteria Rhodomicrobium vannielii and Rhodopseudomonas viridis have been determined. Only a single residue deletion (at position 11 in horse cytochrome c) is necessary to align the sequences with those of mitochondrial cytochromes c. The overall sequence similarity between these cytochromes c2 and mitochondrial cytochromes c is closer than that between mitochondrial cytochromes c and the other cytochromes c2 of known sequence, and in the latter multiple insertions and deletions must be postulated before a ...
Ligand binding properties of horse hemoglobins containing deutero- and mesoheme. The reactions of horse globin reconstituted with proto-, deutero-, and mesoheme have been examined by equilibrium and kinetic methods. In virtually all reactions studied, mesohemoglobin displays the more extreme functional behavior, whereas deuterohemoglobin exhibits behavior which is either very similar to native hemoglobin or intermediate between the two. Our kinetic and equilibrium results indicate that the primary effect of heme modification on the functional properties of hemoglobin is to alter the intrinsic reactivities of the deoxy and liganded conformations. Heme modification does not,...
Male pseudohermaphroditism of the testicular feminizing type in a horse. Features characteristic of the hereditary syndrome of testicular feminization (tfm) were observed in a 7-year-old Quarter Horse. The horse had female body habitus and male psychosexual behaviour. Gonads located in the abdomen were testes and the uterus and cervix were absent. The vagina was normal in depth but ended as a blind pocket. The sex chromosome composition of testicular fibroblast and leucocyte cultures was XY. Construction of a family pedigree revealed a pattern of hereditary transmission similar to that reported for tfm in other mammalian species.
Squamous cell carcinoma in horses. In a review of neoplasm registry records at Kansas State University (1961 through 1971), 58 squamous cell carcinomas were reported in 10 breeds of horses. Mean age of the affected horses was 12.4 years. The head, eye and ocular adnexa accounted for 43.1%, the external male genitalia, 44.8%, and female perineal region, 12.0% of the squamous cell carcinomas, altogether representing 20.2% of 287 neoplasms recorded.
N-acetylserine in horse muscle acylphosphatase. A ninhydrin-negative peptide fraction obtained from tryptic digest of carboxymethyl acylphosphatase was isolated by chromatography on a column of PA 28 Beckman resin and analysed for the amino acid composition. Degradation with carboxypeptidase B and A indicated that the sequence of this peptide was: X-Thr-Ala-Arg. The amino-terminal residue was identified as N-acetylserine by high voltage electrophoresis. It is therefore suggested that the sequence of the NH2-terminal portion of CM-acylphosphatase is N-acetyl-Ser-Thr-Ala-Arg. Digestion with carboxypeptidase A and B indicated also that the COO...
Use of blood typing to confirm principles of coat-color genetics in horses. The chestnut rule in equine coat-color genetics asserts that the inter se mating of chestnut horses never produces bay, black, brown or gray offspring. The gray rule asserts that a gray offspring must have at least one gray parent. Nine alleged exceptions to the chestnut rule, all involving bay offspring, and eight alleged exceptions to the gray rule, including four offspring that were also exceptions to the chestnut rule, were examined for parent-offspring genetic incompatibilities in as many as 17 genetic systems of blood-group markers. In all except one of the 17 cases it was possible to sh...
Equine serum lipids: serum lipoprotein profiles of Morgan and Thoroughbred horses. The serum of lipoproteins of 10 Morgan and 8 Thoroughbred horses were examined by 2 methods of polyacrylamide gel electrophoresis. A significant breed difference in the beta-lipoprotein to alpha-lipoprotein ratio was seen in gradient slab electrophoresis. A breed difference in the number of peaks, but no difference in beta-lipoprotein to alpha-lipoprotein ratio, was found in disc gel electrophoresis. These results have been correlated to indicate differences in charge of alpha-lipoprotein components and in size of beta-lipoprotein components between these 2 breeds of horses.
Equine serum lipids: lipid composition and electrophoretic mobility of equine serum lipoprotein fractions. The serum lipoprotein fractions from 5 Morgan and 5 Thoroughbred horses were isolated by preparative ultracentrifugation, chemically analyzed for lipid composition, and studied by 2 methods of polyacrylamide gel electrophoresis to determine electrophoretic mobility. Breed differences were not seen in the relative percentages of the lipid classes found in the various fractions. Normally, horses, like most animals, carry the majority of their lipid in high-density lipoproteins. Electrophoretically, the only difference seen between breeds occurred on disc electrophoresis where the extra band, whi...
[Preliminary performance test in saddle horses (author’s transl)]. The study of the literature on a preliminary performance test for saddle horses (stallions) is concerned with European countries. Interest is found to be increasing in the various countries. Performance of the test in the Netherlands (since 1966) is described and the various criteria of evaluation are discussed in detail. The intensity of selection based on this test is referred to. In 1974, it was 78 per cent in the Netherlands. Part of studies on the relationship between some results of testing are reviewed. The traction test shows a very low coefficient of correlation with the other parts o...
Luteolysis with prostaglandin F2alpha or an antiserum against an equine pituitary fraction in hysterectomized mares. Luteolysis, determined by corpus luteum weight and progesterone concentration in jugular blood, occurred in uterine-intact and in hysterectomized mares after injection of prostaglandin F2alpha or of an antiserum against an equine pituitary fraction. Results indicated that luteolytic effects of exogenous prostaglandin F2alpha and inhibition of the endogenous luteotrophic activity of the hypophysis (pituitary gland) by antiserum did not involve the uterus.
Carbohydrate composition of horse spleen ferritin. The carbohydrate composition of horse spleen ferritin was studied. 1 mol of the apoferritin, the protein moiety of ferritin, contains 25 mol of hexose, 3 mol of hexosamine and 10 mol of fucose. Same carbohydrate composition was detected in the apoferritin from iron rich ferritins. These results indicate that horse spleen ferritin is composed of non-identical subunits as regards its carbohydrate composition.