Topic:Species Comparison
Species comparison in horses involves examining the physiological, anatomical, and behavioral differences and similarities between horses and other animal species. This area of study can provide insights into the evolutionary adaptations and ecological roles of horses. Researchers often focus on aspects such as digestive systems, locomotion, sensory capabilities, and social structures to understand how horses have evolved to meet their environmental and survival needs. Comparative studies may also explore genetic differences and similarities, contributing to a broader understanding of species evolution and adaptation. This page aggregates peer-reviewed research and scholarly articles that analyze various aspects of species comparison involving horses, highlighting significant findings and methodologies used in the field.
Gel electrophoresis of rotavirus RNA derived from six different animal species. Rotavirus RNA prepared from calf, pig, mouse, deer, foal and dog-adapted human isolates was compared using polyacrylamide gel electrophoresis. Reproducible differences in the RNA migration patterns were found between all isolates. There were 11 clearly resolved segments in the pig, mouse and foal samples. The calf rotavirus RNA and deer rotavirus RNA separated into 9 bands and 10 bands, respectively. The dog-adapted human virus migrated in 12 bands, and this probably results from the complex passage history of the original human rotavirus isolate.
Metabolism of progesterone by placentas from several mammalian species in vitro. 20-alpha-Hydroxysteroid oxidoreductase (20-alpha-HSDH) activity and 20-alpha-dihydroprogesterone concentration (20-alpha-DHP) reach peak values in the human placenta after vaginal delivery. To determine if these findings are unique to the human, we measured 20-alpha-HSDH activity as well as endogenous progesterone (P) and 20-alpha-DHP concentration in the soluble supernatant fraction of placental tissues obtained from rodents (rat, rabbit, guinea pig), ungulates (horse, zebra, giraffe, cow), and primates (squirrel monkey, orangutan, man). P concentration was very low in rodents (mean 0.60 ng/m...
A cytogenetic study of the Caspian pony. The group of Caspian ponies studied contained some animals with 65 chromosomes and others with 64 chromosomes. The morphology and G-banding pattern of the chromosomes resembled those of Equus caballus and E. przewalskii. The karyogram of animals with 65 chromosomes was identical to that of the cross between E. caballus and E. przewalskii. It is suggested that the Caspian pony is the product of natural hybridization between E. caballus and E. prezwalskii. Low reproductive effeciency of the Caspian pony is suggested as the cause of decline in the population of these animals.
[Distribution and species makeup of the horse botflies in the Buryat ASSR and Mongolian Peoples’s Republic (Oestridae, Gastrophilidae)]. In Burjatia and Mongolia the infection of horses with rhinoestrosis and gastrophilosis accounts for 97.8-99.2% and 98.9-99.5%, respectively at the infection intensity 34 to 721 and 55 to 1473 larvae. The sheep botfly is represented by one and the horse botfly by six species; they have one generation a year. The flight of the horse botfly begins from the second decade of June and ends in the second decade of September; the flight of the sheep botfly begins in the third decade of June and ends in the first decade of September. The pupil stage lasts 20 to 61 days.
Ultrastructure of the pigment epithelium and the photoreceptors in the retina of the horse. An electron microscopic description was given of the pigment epithelium and the photoreceptors of the horse retina. Duplicity (rods-cones) of the horse retina was proven histologically; the retina was classified as an "E" retina, which indicates predominance of the rod system.
Evolutionary conservation of equine gc alleles and of Mammalian gc/albumin linkage. Ancient origin of the equine vitamin D binding protein (Gc) polymorphism is suggested by the finding of two alleles, Gc(F) and Gc(S), in each of three equine subgenera, Equus, Asinus and Hippotigris. The equine Gc and albumin loci are closely linked (lod score = 6). Although no recombinants were observed, the data are not inconsistent with a map distance similar to the 2 centimorgans reported for the human albumin/Gc linkage relationship. Gametic association between the Gc(F) and Alb(F) alleles appears probable in the American Standardbred horse, perhaps as a result of population structure. Si...
Improved measurements of shear modulus and pleural membrane tension of the lung. The continuum solution for the deformation of an elastic half space covered by a membrane is used to interpret measurements of the indentation of lung lobes under a column of fluid. The shear modulus mu of the underlying parenchyma is found to be approximately 0.7 times transpulmonary pressure, independent of species size. The tension in the pleural membrane T increases rapidly with increasing membrane area. For dog lungs, the value of T is 10(3) to 10(4) dyn/cm. For the larger species tested, pigs and horses, T is larger. The continuum solution shows that a concentrated force applied to the p...
Hereditary multiple exostoses: clinicopathologic features of a comparative study in horses and man. Investigation of hereditary multiple exostoses in horses under controlled research conditions for 10 years and epidemiologic studies that have spanned up to five generations of human families contain notable similarities. The present study demonstrated that a single dominant autosomal gene is responsible for hereditary multiple exostoses in horses and man. Affected individuals transmit this trait to approximately 50% of their progeny, whereas nonaffected individuals do not transmit the condition to their offspring. The tumors in affected horses are most often present at birth. They tend to be ...
Total fibre numbers in cross sections of the semitendinosus in athletic and non-athletic horses and dogs. The numbers of fibres in the complete cross section of the semitendinosus were estimated in 58 equines and 59 canines of differing types. Animals selected for swiftness--thoroughbred horses and greyhounds--have a greater number of fibres in a cross section of their semitendinosus than other members of their species, whether as neonates or as adults. The numbers of fibres in the cross section increases during growth in both types of animal in each species.
Variability in erythrocyte deformability among various mammals. Deformability is an important aspect of erythrocyte physiology and has been extensively studied using human red cells. We have studied erythrocytes from 25 different animals using a viscometric technique. Erythrocyte diameters ranged from 3.3 microns in the goat to 11.4 microns for the elephant seal. Erythrocytes from most species deformed readily when a fluid shear stress was applied. A deformability index of the stressed cell defined as (length - width)/(length + width) correlated with cell size. The erythrocytes of four animals (pygmy goat, goat, Batanga horse, and miniature horse) deformed...
Molecular cytogenetics of the Equidae. I. Purification and cytological localization of a (G + C)-rich satellite DNA from Equus przewalskii. A (G + C)-rich density satellite DNA (rho = 1.713 gm/cc) has been purified from splenic DNA of Przewalski's horse, Equus przewalskii, by successive equilibrium density gradient centrifugations. The purified satellite, which may comprise as much as 29% of the total DNA, renatures rapidly; however, analyses of native, single-stranded, and reassociated molecules by analytical ultracentrifugation and melting properties suggest that some sequence heterogeniety exists in the 1.713 gm/cc satellite. Complementary RNA (cRNA) transcribed from satellite DNA has been utilized for in situ hybridization stu...
Comparative pathology of glomerulonephritis in animals. Glomerulonephritis constitutes an important category of renal diseases in animals and has been recognized with increasing frequency in the last decade. We report here the comparative morphologic aspects of glomerulonephritis as a naturally occurring disease of animals. We briefly review the immunopathogenesis of glomerulonephritis. The morphology of renal lesions occurring in glomerulonephritis in dogs, cats, cattle, sheep, horses and swine has been reviewed with emphasis on the range and specificity of various glomerular lesions and on the comparison of lesions between various species. A dist...
Hemoglobin polymorphism in Equus przewalskii and E. caballus analyzed by isoelectric focusing. 1. Through the use of isoelectric focusing and peptide analysis, the hemoglobins of Przewalski's horse. Equus przewalskii and the domestic horse, E. caballus have been compared. 2. Przewalski's horses have two separate alpha-globin chain polymorphisms similar to domestic horses. Each hemoglobin phenotype could be accurately determined by isoelectric focusing. 3. Confirmation of the electrofocusing hemoglobin determinations was made by comparison to amino acid composition analyses of purified tryptic peptides and by analysis of the rare hemoglobins phenotypes observed in a family of Norwegian t...
DNases in milk and blood sera from different species. DNases were demonstrated in samples of colostrum and blood serum from man and various domestic animals. The measurable DNase activity recorded was highest in samples from cat and dog and lowest in samples from goat, horse, pig and sheep. In contrast to DNases produced by certain bacteria, these enzymes were thermo-labile and the activity was maximal in the area pH 5.0–5.5. A modification of an agar medium originally described for the demonstration of bacterial DNases was found to be suitable for assays of DNases from colostrum, milk and serum. DNaser ble påvist i prøver fra kolostrum og bl...
A comparative histochemical study of intrinsic laryngeal muscles of ungulates and carnivores. The intrinsic laryngeal muscles of the horse, donkey, sheep, ox, pig, dog and cat were examined for myosin ATPase, following acid and alkali pre-incubation, SDH and M-alphaGPDH activities. In all laryngeal muscles two fibre types, betaR and alphaR, belonging to slow and fast-contracting, fatigue-resistant motor units (types S and FR) were present in different proportions. The alphaW fibre type, belonging to fast-contracting and fatigue-resistant motor units was absent (type FF). The alphaR fibres of the dog and the cat were subdivided into groups by the various degrees of acid stable myosin AT...
Comparative studies on serum arginase and transaminases in hepatic necrosis in various species of domestic animals. Serum concentrations of arginase, glutamic pyruvic transaminase (SGPT) and glutamic oxaloacetic transaminase (SGOT) in dogs, cats, horses, cattle, sheep and pigs were determined before and after oral administration of CCl(4) at doses known to cause hepatic necrosis. Following CCl(4) administration, serum concentration of arginase and SGOT increased to a level of diagnostic significance in all animals. SGPT increased markedly in dogs and cats and marginally in 1 of 3 cattle and 2 of 3 pigs. In the surviving animals, the serum concentration of arginase returned to normal range much earlier than ...
Shunting in intracranial microvasculature demonstrated by SEM of corrosion-casts. The use of methyl methacrylate corrosion-casts has made it possible to examine the intracranial microvasculature on a three-dimensional scale with the scanning electron microscope. By this means we have compared regions of four cerebral and cerebellar arteries among three domestic animal species. The results of this study suggest that there are from one to three different levels of interarteriolar anastomosis between branches of the same or adjacent vessels. In the horse and ox anastomoses were demonstrated (1) at the level of the precapillary arterioles, (2) along the arterioles, and (3) betw...
[Heterophile haemagglutinogens on pig, canine and human thymocytes (author’s transl)]. Immunization of sheep or horse with pig, canin or horse thymocytes produces heteroagglutinating antibodies, which allow to define two heterophile antigens:--the first one, HC, immunogen for sheep, is localized on pig, human and canin thymocytes, as well as on red blood cells of the two latter species;--the other, HCP, immunogen for horses, is situated on the red blood cells and thymocytes of the same three species. HC is distributed on various cells and in similar fashion in pig and human, except for the pig red blood cells.
Physiological implications of microbial digestion in the large intestine of mammals: relation to dietary factors. The rate of digesta marker passage through the large intestine of the dog, pig, and pony correlated with the relative length and degree of sacculation of the colon. Volatile fatty acids (VFA), the end products of microbial digestion of all forms of carbohydrate, were the major anions present in large intestinal contents of all three species. Total VFA concentration was little affected by the feeding of high-versus low-fiber diets. VFA were rapidly transported across colonic mucosa of all three species. Results of comparative studies indicate that production and absorption of VFA are important ...
Common membrane neoantigens on bovine papilloma virus-induced fibroma cells from cattle and horses. Cultured cells from bovine papilloma virus (BPV)-induced fibroblastic tumors and normal dermis of cattle, horses, and hamsters were examined for cell membrane or internal neoantigens, using the indirect immunofluorescence technique. Sera from cattle and horses bearing BPV-induced fibromas cross reacted with cell membranes of tumor, but not with normal dermal cells of both species. The reaction could be blocked with homologous, but not heterologous, serum of these 2 species. Immunofluorescence was not detected with sera from hamsters bearing BPV-induced sarcomas if incubated with bovine, equine...
The mean fibre area of the semitendinosus, diaphragm and pectoralis transversus muscles in differing types of horse and dog. The mean fibre areas of samples from m. semitendinosus, m. diaphragma and m. pectoralis transversus of thoroughbred horses and greyhounds have been compared with those in similar samples from other members of their species. Athletes (greyhounds and thoroughbreds) have larger fibres in the semitendinosus and diaphragm than their fellows. However, the mean area of pectoralis transversus is similar in the two types of animal within each species. During growth the mean fibre areas increase to a greater extent in athletes than in non-athletes. Detraining adult greyhounds for a period of one year di...
Fourier transform infrared spectroscopic study of molecular interactions in hemoglobin. Infrared absorption spectra of the alpha-104 (G11) cysteine SH group have been observed for aqueous solutions of hemoglobin derivatives from humans, pigs, and horses. The center frequencies ((nu)SH) show ligand sensitive patterns that are similar for the three species, with (nu)SH (HbCO) <(nu)SH (HbO(2) ~ HbCN) < (nu)SH (Hb(+)) <<(nu)SH (deoxyHb) for human and pig hemoglobins. The alpha-104 SH group is most strongly H-bonded (smallest (nu)SH), has the greatest range of (nu)SH (Hb ? HbCO) in human hemoglobin, and is least strongly H-bonded and has the smallest range of (nu)SH (Hb ? HbCO) in hor...