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.
Vasculature of the equine and canine iris. Methyl methacrylic casts were prepared and tissue was freshly collected for histologic examination to compare the vascular supply and the structure of the vessels of the iris in the adult horse with those of the dog. In the horse, ciliary blood vessels divided in the iris and formed a complete major arterial circle of the iris. In the dog, the ciliary blood vessels divided in the ciliary body and, by means of recurrent branches, formed a complete arterial circle. From this circle, radial arteries extended toward the pupillary margin. The radial vessels in the horse were nearly straight and joi...
Immunological properties of two related fragments from human and equine growth hormones. The immunological properties of a synthetic human growth hormone fragment comprising the amino acids 73 through 128 and of the homologous natural horse growth fragment formed by amino acids 73 through 123, have been comparatively studied. Antisera obtained in rabbits inoculated with the native human hormone or with the fragments, were used. By hemagglutination experiments both fragments have the same reactivity toward the anti-human growth hormone serum, but complement fixation curves detect the existence of at least two populations of antibodies presumably originated against the sequence 73-1...
Horner’s syndrome in large animals. The sympathetic nervous innervation of the head was surgically transected in the horse, cow, sheep and goat. The site of transection was preganglionic in all 4 species and ganglionic-postganglionic in 2 additional horses. The Horner's syndrome, manifested as a result of the iatrogenic lesion, varied with the species. Ptosis was the most constant sign in all species. Unilateral sweating over the face and proximal neck, particularly at the base of the ear, was the most prominent feature in the horse. The cow revealed distension of vasculature and cutaneous heat of the pinna, and a reduced produc...
Bovine reaginic antibody III. Cross-reaction of antihuman IgE and antibovine reaginic immunoglobulin antisera with sera from several species of mammals. Using antisera specific for the heavy chain of human IgE and bovine reaginic immunoglobulin, the degree of cross-reaction amongst sera from pig, rat, rabbit, guinea pig, goat, cow, horse, dog, cat and human was tested. Antihuman IgE antiserum gave strong reactions with pig, rabbit, cow, goat and human sera (100% to 15.1%) and weak reactions with rat, guinea pig, horse, dog and cat sera (10.1% to 3.22%). Antibovine reagin antiserum produced a considerable amount of cross-reaction with sera from pig, rat, rabbit, goat, horse and human (43.6% to 20.1%) with limited reactions with guinea pig, dog ...
A comparative study of the mechanical properties in aging alveolar wall. Alveolar wall from the lung of aging humans shows a progressive decrease in maximal extensibility, which should follow an increase in resting tissue length rather than a reduction in maximal length. An increase in resting tissue length is compatible with the change in lung volumes and reduction in elastic recoil that occurs with time. A model of the lung was used to compare the effects of a change in resting tissue length in diminishing elastic recoil with that of a reduction in the volume density of the elastic elements (emphysema). Such differentiation is important in selecting an animal tha...
Influence of foetal genotype on the follicle-stimulating hormone:luteinizing hormone ratio of pregnant mare serum gonadotrophin. Rat testicular radioreceptor assays specific for FSH and LH were used to determine the FSH:LH ratio of PMSG produced by horse, donkey, mule and hinny conceptuses. Measurements of FSH and LH activities in PMSG produced both in vivo and in vitro by the four types of conceptuses showed that the genotype of the foetus markedly influences the FSH:LH ratio of PMSG. The FSH:LH ratio of PMSG produced by the horse conceptus was around unity whereas the ratio of PMSG produced by the donkey conceptus was as low as 0-2. Furthermore, the hybrid mule and hinny conceptuses both produced PMSG with an FSH:LH r...
New techniques to measure blood cholinesterase activity in domesticated animals. A macromethod and a semimicromethod were developed to measure erythrocyte acetylcholinesterase activity in cattle, sheep, goats, horses, dogs, and swine, and to measure plasma cholinesterase activity in horses, dogs, and swine. Comparison of the 2 methods with erythrocytes of sheep, cattle, goats, and horses indicated both methods gave similar results. They can be done in a shorter time and are more sensitive than Michel's method. Normal deltapH values per minutes, with standard deviations for blood cholinesterase activity of animals of different ages, sexes, breeds, and species, were: 0.76 +/...
The activity of purine salvage pathway enzymes in murine and horse models of congenital and acquired dysimmunity. Previous studies of human congenital immunodeficiency states and in vitro observations of lymphocyte response to mitogens have implicated two purine salvage pathway enzymes, andenosine deaminase (ADA) and nucleoside phosphorylase (NP), as critical in the normal maturation and/or function of the immune system. Based on this information, ADA and NP activities were examined in a variety of congenital and acquired animal models of dysimmunity. The animals studied herein included: congenitally athymic (nude) mice; congenitally asplenic mice; congenitally athymic-asplenic mice; motheaten mice; New Z...
Transmission of the cytochrome c structural gene in horse-donkey crosses. Donkey cytochrome c was shown to differ from horse cytochrome c by having a serine in position 47 rather than a threonine. The rest of the amino acid sequences are identical. Mules and hinnies, both males and females, carry equal amounts of horse and donkey cytochromes c. The same ratio is found in hinnies in preparations from heart tissue and from skeletal muscle. These results demonstrate that cytochrome c is transmitted in horse-donkey crosses as a simple Mendelian character which is neither sex-linked nor shows dominance. The cytochrome c gene is therefore located in the nuclear genome, as...
Amino acid composition of casein isolated from the milks of different species. Casein was isolated from the milks of the following species: cow, horse, pig, reindeer, caribou, moose, harp seal, musk-ox, polar bear, dall sheep, and fin whale. The caseins were subjected to acid hydrolysis, the resultant amino acids were converted to their n-butyl-N-trifluoroacetyl esters, and the amino acid composition of the caseins was determined by gas chromatographic analysis of these esters. Notable among the results was the close similarity, with respect to amino acid composition, of reindeer and caribou caseins. The results of the amino acid analyses of the other caseins are present...
[Cochliatoxum periachtum Gassovsky, 1919, entodinimorphic Ciliate of the horse digestive tract]. The topography of Cochliatoxum periachtum is studied. The cuticle is very thick. The digestive, nuclear and excretory systems are located in the ectoplasm, they are not surrounded by the mesoplasm. The endoplasm is very large, it contains vegetable inclusions. By the features of its topography, this species is similar to some species belonging to the Family Ophryoscolescidae and, especially, to Eudiplodinium giganteum.
[Comparative electrophoretic study of the molecular forms of alkaline phosphatase in the leukocytes of agricultural animals]. The alkaline phosphatase enzyme, isolated by Morton's method from leukocytes of sheep, goats, and pigs gave after agarose elctrophoresis two isoenzyme fractions moving to the positive pole at the sites of the alpha 1- and alpha 2-globulins of the blood serum. In bovine leukocytes, besides these two fractions there was a third one that moved more slowly in the zone of the beta-globulins. In horses the alkaline phosphatase of leukocytes produced a wide band within the zones of the beta-globulins and the albumins. It was established that the proportion between the individual isoenzyme fractions o...
Strain differences in Echinococcus granulosus, with special reference to the status of equine hydatidosis in the United Kingdom. The genetics of speciation in the genus Echinococcus are briefly discussed. As the organism is a hermaphrodite and multiplies asexually in the larval stage, the genetic mechanism for the ready production of new strains is inherent in the life-cycle. Some biological, biochemical and nutritional differences between the horse and sheep strains are examined. The sheep strain may be grown to sexual maturity, in vitro, in a diphasic system; the horse strain fails to grow in such a system. Differences have also been demonstrated between the soluble proteins of the two strains. The sheep strain is inf...
Drug interactions in the horse: effects of chloramphenicol, quinidine, and oxyphenbutazone on phenylbutazone metabolism. The plasma half-life of phenylbutazone in horses was not increased after pretreatment with chloramphenicol or quinidine, but was increased after oxyphenbutazone. This increased plasma half-life after oxyphenbutazone is consistent with observations in other species and suggests that oxyphenbutazone inhibits the metabolism of phenylbutazone in horses. Lack of inhibition of phenylbutazone metabolism in the horse by chloramphenicol and quinidine is inconsistent with results obtained in other species.
Comparative study of the dorsal motor nucleus of the vagus nerve. Quantitative studies were made of cells in the dorsal motor nucleus of the vagus nerve in the horse, dog, cat, pig, sheep, goat, and calf. This nucleus was larger in ruminants than in nonruminants. Some cells in all parts of the nucleus supplied visceral structures in the head, cervical, thoracic, and abdominal regions; however, a definite topographic localization did exist within the nucleus. Eighty percent of the cells which supplied the abdominal viscera were in the rostral and rostral-middle regions. The cells which supplied the thoracic viscera were distributed almost equally within the r...
The activity of some nucleolytic enzymes in semen and in the secretion of the male reproductive tract. The activity of 5'-nucleotidase (EC 1.3.5), cyclic nucleotide phosphodiesterase (EC 2.1.4.17), non-specific phosphodiesterase (EC 3.1.4.1) and ribonuclease (EC 1.7.7.16)has been investigated in the seminal plasma of whole semen and in the secretions of the seminal vesicle, prostate and epididymis of the bull, boar, ram, stallion, jackass, rabbit and man. Bull seminal plasma showed the highest activity for 5'-nucleotidase, cyclic nucleotide phosphodiesterase and ribonuclease; in contrast, stallion and jackass semen were very poor in these enzymes. Ram, rabbit and boar seminal plasma showed inte...
A comparative study of experimental and spontaneous emphysema. Normal lung architecture of the rat, mouse, hamster, horse, and human was compared to that of emphysematous lungs from the same species by utilizing a light microscope and a scanning electron microscope (SEM). The results obtained by SEM examination of normal and emphysematous lungs corresponded to those obtained with the light microscope. However, the SEM provided a view of alveoli and airway morphology not obtainable with the light microscope. Because of the variability in pore size and number of pores per alveolus, a pore-to-alveolus ratio was determined with the SEM on the normal lungs of ...
Comparative studies on the gastric glycopeptide in eleven animal species. 1. Glycopeptides in the stomachs of eleven mammalian species, including human, rabbit, horse, cow, pig, goat, sheep, dog, cat, guinea pig and rat were assayed by determining the carbohydrate content of materials which remained after proteolysis. 2. The glycopeptide content was higher in the mucosa than in the muscular layer including serosa, especially in the porcine stomach and the fourth stomachs of the ruminants than in the stomachs of any other animals. 3. The glycopeptide, which was stained with both alcian blue and PAS, was absent or sparingly present in the mucosae of the human, rabbit,...
Serological relationships between rotaviruses from different species as studied by complement fixation and neutralization. Human, piglet, mouse, foal, lamb, calf and rabbit rotaviruses all infected, but could not readily be subcultured in LLC MK2 cells. Cells infected with mouse and calf rotaviruses reacted by indirect immunofluorescence (FA) with convalescent serum from children, piglets, mice, foals, lambs, calves or rabbits, taken after rotavirus infection. Human, calf, piglet, mouse and foal rotaviruses reacted with human, calf, mouse, foal and lamb convalescent serum by complement fixation (CF). It was not possible to distinguish between different rotaviruses by CF or FA. Neutralization tests, however, detect...
Oldest horse brains: more advanced than previously realized. Previous interpretations of early horse brains were based on an incorrectly identified fossil endocast, now believed to be from a condylarth. Newly prepared endocasts of Hyracotherium, the oldest horse and one of the earliest perissodactyls, reveal a relatively larger brain, with a more expanded neocortex, than existed in the condylarth ancestors of perissodactyls. Fifty million years ago, horse brains had suprasylvian, ectolateral, and lateral sulci, but the frontal lobe was undeveloped.
Horse, ass, and mule chromosomes. Karyotypes of the horse with 64 chromosomes, the ass with 62 chromosomes, and the mule with 63 chromosomes are presented. The chromosome complements of each species and their mule hybrid are analyzed and compared.
Glucose metabolism of mammalian erythrocytes. Under physiological conditions, erythrocytes of the horse metabolized 638 +/- 37 (+/-SE) nmoles glucose/ml cells/hr at 37 degrees C compared to 942 +/- 31 for the cat, 1,329 +/- 44 for the dog, and 1,485 +/- 43 for man. On an absolute basis, pentose phosphate metabolism was similar between species, with species differences in erythrocyte glucose tulization attributable to differences in Embden-Meyerhof pathway metabolism. By examining pentose phosphate pathway recycling, it appears that some functional compartmentation exists within erythrocytes.