Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Comparative Study
Comparative studies in equine research involve the systematic analysis of different horse breeds, management practices, or physiological responses to identify variations and similarities. These studies are instrumental in understanding how different factors influence health, performance, and behavior in horses. Common areas of comparison include genetic traits, nutritional requirements, disease resistance, and response to training. By evaluating these differences, researchers can develop targeted strategies for breeding, healthcare, and training. This page aggregates peer-reviewed research studies and scholarly articles that focus on the methodologies, findings, and implications of comparative studies in the context of equine science.
Isolation and characterization of four basic proteins from horse eosinophilic granules. Four new basic proteins were isolated from horse eosinophils and purified. The eosinophils release these proteins after permeabilization with saponin and degranulation stimulized by guanosine 5'-O-thiotriphosphate. The proteins were separated and purified on a Superose P12- and a Mono S-column by fast protein liquid chromatography. The amino acid composition, the relative molecular mass, the isoelectric point and the partial N-terminal sequence of the four proteins were determined. Papain-activation and ribonuclease activity of the four proteins were tested for comparison with the human eosino...
Competitive inhibition of lipolytic enzymes. IX. A comparative study on the inhibition of pancreatic phospholipases A2 from different sources by (R)-2-acylamino phospholipid analogues. The inhibitory power (Z) of a number of (R)-1-alkyl-2-acylamino phospholipid analogues was determined for three mammalian phospholipases A2 from pig, ox and horse pancreas. All three enzymes display a clear preference for anionic (phosphoglycol) inhibitors over the zwitterionic (phosphocholine) derivatives; this effect is most pronounced for the bovine enzyme. Upon variation of the 1-alkyl chain length, the bovine and equine phospholipases, like the porcine enzyme in previous studies, show an optimum in Z for a six-carbon alkyl group. The introduction of a double bond in the 2-acylamino group ...
Studies on the substrate specificity of the proteinase of equine infectious anemia virus using oligopeptide substrates. The proteinase of the equine infectious anemia virus (EIAV), a lentivirus closely related to human immunodeficiency virus (HIV), was purified from concentrated virus. The specificity of the enzyme was characterized using oligopeptides representing naturally occurring cleavage sites in the Gag and Gag-Pol polyproteins. The length of the substrate binding pocket was found to be 1-2 residues longer than that of HIV proteinases. Although the EIAV and HIV proteinases cleaved most of the peptides at the same bond, some were hydrolyzed by only the EIAV enzyme. Oligopeptides representing cleavage site...
Serum levels of testosterone and oestrogens in normal and infertile stallions. The serum concentrations of testosterone and oestrogens were determined in stallions classified as geldings, normal (according to age) or infertile (azoospermic). There were significant differences in testosterone and oestrogen levels between the groups. Normal concentrations of testosterone and total oestrogens were attained after 16 months of age. Castrated and immature horses ( 4 years). The results suggest that serum levels of testosterone and total oestrogens may provide a sensitive index of the endocrine function of the testis in male horses.
Proto-oncogene of genomic DNA, related to the human epidermal growth factor receptor (EGFR) gene, from clinically normal domestic animals. Genomic DNAs of cattle, horses, pigs, dogs, cats and chickens were surveyed using Southern blot hybridization analysis, with a human EGFR cDNA fragment. Several bands with different numbers and molecular weights were observed under the condition of low stringency in the individual animal species. The bands showing DNA polymorphism were observed among bovine genomic PstI-digested DNAs from 4 individuals and EcoRI-digested genomic DNAs from 4 chickens. These results may provide basic data which are useful for analysis of tumorigenetic mechanisms in domestic animals.
[Spavin in horses–clinical, radiological and scintigraphic findings]. Both hock joints were examined clinically, radiologically and scintigraphically in 80 horses with special regard to bone spavin. The positive x-ray and bone scan results corresponded in most cases. It was evident that there was no correlation between degree of lameness and/or extent of radiological findings and increased radioactive uptake in the joint. Scintigraphic evaluation may demonstrate early changes at the onset of bone spavin as well as the frequent bilateral nature of the condition.
Clinical anatomy of the equine head. This topical presentation emphasizes the structures most likely to be encountered in the diagnosis and treatment of diseases of the equine head. Most of the approaches are from superficial to deep. Anatomic variations associated with aging are described. The larynx and guttural pouches are not included in this article.
Placentas and foetal health. The placenta provides many critical services to the developing foetus. Proper placental implantation, growth and function are necessary for normal foetal growth and development. Placental structure varies widely among species but all mammalian placentas have a convoluted materno-foetal interface that may be quite simple or highly complex; the more complicated interdigitations tend to characterise smaller placentas that have limited areas of contact between the placenta and the endometrium. The intimacy of the contact between maternal and foetal tissue varies from apposition only, as in the equ...
Maturation of the central nervous system: comparison of equine and other species. This review covers the development and maturation of the cerebellum of the horse and compares this developmental sequence with that of man, mouse and chicken. These comparisons attempt to correlate morphological and neurochemical features, developmental time and functional performance necessary for survival at birth. Although there is great disparity between these 3 species, the basic anatomical structures of the cerebellum are present as are specific cellular groups, synapses and neurochemical markers. In addition to this structural homogeneity, other attributes of the cerebellum are its easi...
Maturation of insulin and glucose responses to normal feeding in foals. Postprandial insulin and glucose concentrations were measured in 3 Arabian and 3 Thoroughbred foals at 1 day, 1 week, 1 month and 3 months of age. Prefeeding serum insulin concentrations were similar in foals at 1 day (25.9 +/- 5.1 pmol/L), 1 week (32.4 +/- 5.8 pmol/L), and 1 month (38.2 +/- 7.9 pmol/L), but had increased significantly to 131.0 +/- 20.2 pmol/L at 3 months of age (P < 0.05). There was significantly increased serum insulin secretion after a feed in foals at 3 months of age (P < 0.05) when compared with that at younger ages. Prefeeding serum glucose concentrations ranged fr...
Comparative immunohistolocalization of carbonic anhydrase isozymes I, II and III in the equine and bovine digestive tract. Immunohistochemical localizations of carbonic anhydrase isozymes (CA-I, CA-II and CA-III) in equine and bovine digestive tracts were studied. In the horse, epithelial cells in both the oesophagus and non-glandular part of the stomach lacked all three isozymes. In contrast, surface epithelial and parietal cells in the glandular region of the stomach showed reactivity for CA-II. In the small intestine, absorptive columnar cells covering the villi in the duodenum were positive for CA-II. The epithelium of the jejunum and ileum lacked all three isozymes. In the large intestine, CA-II was detected ...
Growth hormone (GH) secretory pattern and GH response to GH-releasing factor (GRF) or thyrotropin-releasing hormone (TRH) in newborn foals. The present study was undertaken to assess GH secretory profiles in 12 light-breed foals and their dams during forty days after delivery, and the possible influence of GRF and TRH on plasma GH concentrations in these newborn foals. GH secretory pattern was pulsatile in one day- as well as in forty days-old foals. The number of secretory spikes (10 per 24 h) did not vary between days 1 and 40. In the same times, GH secretion did not show any circadian rhythm either in foals or in their dams. Mean daily plasma concentrations (measured through blood samples collected every 20 min for 24 h) were l...
Effect of influenza A/equine/H3N8 virus isolate variation on the measurement of equine antibody responses. This study has tested the effect of using homologous or heterologous equine influenza A virus isolates to evaluate serum antibody levels to influenza A virus in vaccinated and naturally-infected horses. In addition, the potential effect of antigenic selection of virus variants in egg versus tissue culture propagation systems was studied. Serum antibody levels in samples from horses recently infected with a local influenza A virus isolate (A/equine 2/Saskatoon/1/90) or recently vaccinated with a prototype isolate (A/equine 2/Miami/1/63) were assessed by hemagglutination inhibition and by single...
Clinical view of disturbances in equine foetal maturation. This review summarises comparative aspects of equine pregnancy and birth. The allantochorion covers the entire endometrial surface of the mare's uterus and the placenta is microcotyledonary and epitheliochorial in structure. The foetus has, therefore, to pass through the allantochorion at birth. The umbilical cord has amniotic and allantoic portions and remains intact after delivery, enabling an arterial venous circulation to be maintained for several minutes. Maternal IgG does not cross the placental barrier and passive transfer post-natally is essential for immune status. Gestation in Thorou...
Foetal endocrine maturation. In domestic ruminants such as the sheep, birth is effected through sequential maturation of the foetal hypothalamic-pituitary-adrenal (HPA) axis, leading to the increased output of cortisol. Factors regulating foetal pituitary adrenocorticotrophin (ACTH) secretion have been delineated, and these include corticotrophin releasing hormone (CRH), arginine vasopressin, prostaglandin (PG) E2 and endogenous opioids. The pre-partum increase in foetal plasma ACTH is associated with a rise in pro-opiomelanocortin (POMC) mRNA in the foetal pars distalis, and with an altered pattern of POMC post-translati...
A novel response of anion transporter in equine erythrocytes to a fluorescent substrate, N-(2-aminoethyl sulfonate)-7-nitrobenz-2-oxa-3-diazole (NBD-taurine). This report describes a unique response of the anion transporter in equine erythrocytes to the fluorescent substrate N-(2-aminoethyl sulfonate)-7-nitrobenz-2-oxa-3-diazole (NBD-taurine). Equine erythrocytes showed fluxes of NBD-taurine both inward and outward at rates considerably slower than those in human cells. These fluxes were completely abolished by a typical anion transport inhibitor, 4,4'-diisothiocyanostilbene-2,2'-disulfonate. Furthermore, NBD-taurine competitively inhibited the uptake of phosphate in equine red cells with an inhibition constant of phosphate that was slightly higher ...
Duodenal perforations and gastric ulcers in foals. The history, clinical signs, post mortem and histopathological findings from two foals with perforating gastroduodenal ulcers and one foal with a non-perforating gastric ulcer are compared with those of other species with similar lesions. Two of the foals had several erosions in the oesophageal mucosa and the condition had been associated with strictures in the duodenum. The cause of the disease remains obscure but a possible connection with stress has been suggested.
A comparison of responses to analgesia of the navicular bursa and intra-articular analgesia of the distal interphalangeal joint in 59 horses. Analgesia of the distal interphalangeal (DIP) joint and of the navicular bursa was performed independently in the lame or lamer forelimb of 59 horses, in which lameness was significantly improved by perineural analgesia of either the palmar digital or palmar (abaxial sesamoid) nerves. In 3 horses no improvement was detected. Lameness was improved by analgesia of the DIP joint but there was no response to analgesia of the navicular bursa in 3 horses. In 12 horses, lameness was improved by analgesia of the navicular bursa but intra-articular analgesia resulted in no change. Forty-one horses resp...
Ground reaction force patterns of Dutch warmblood horses at normal trot. This study was undertaken to establish limb loading patterns of sound horses at the trot, to provide a data base against which results for lame horses could be compared. Ground reaction force (GRF) data were collected from 20 clinically sound Dutch Warmblood horses. The data from at least 5 stance phases of each limb were averaged after standardisation to the animal's body mass and to the stance phase duration and resulted in 'representative' GRF data. The symmetry in the vertical GRF peak amplitudes, impulses and the stance phase duration comparing left and right limbs exceeded 97%. By averag...
Characterisation of equine influenza isolates from the 1987 epizootic in India by nucleotide sequencing of the HA1 gene. Two A/Equi-2 (H3N8) isolates were obtained during the 1987 Indian equine influenza epizootic. The sequence of the Ludhiana/87 HA1 gene revealed that this isolate was very similar to recent European and North American isolates of equine influenza. In contrast, the Bhiwani/87 HA1 gene was nearly identical to the Miami/63 prototype H3 sequence. These results support the antigenic analysis previously carried out on these isolates using monoclonal antibodies. However, the finding that Bhiwani/87 is so similar to Miami/63, coupled with the finding that equine H3N8 influenza viruses have previously b...
Molecular organization of the plasma membrane in the post-acrosomal region of some farm animals. According to the distribution of IMP, three different regions can be recognized on PF of the post-acrosomal plasma membrane of bull, ram, and boar spermatozoa. They are: (1) a region with linear aggregation of IMP, (2) a region with fewer and scattered IMP, and (3) a region with more numerous IMP. In the last two regions IMPs are randomly distributed or a clustering of certain particles is visible. In stallion spermatozoa the last two areas are undistinguishable. There are evident interspecies differences in the arrangement of linear aggregations of IMP which are characteristic for each specie...
Mechanical implications of collagen fibre orientation in cortical bone of the equine radius. Mechanical test specimens were prepared from the cranial and caudal cortices of radii from eight horses. These were subjected to destructive tests in either tension or compression. The ultimate stress, elastic modulus and energy absorbed to failure were calculated in either mode of loading. Analysis was performed on the specimens following mechanical testing to determine their density, mineral content, mineral density distribution and histological type. A novel technique was applied to sections from each specimen to quantify the predominant collagen fibre orientation of the bone near the plane...
Breathing periodicity in intact and carotid body-denervated ponies during normoxia and chronic hypoxia. Periodic oscillations in pulmonary ventilation (VI), tidal volume (VT), and inspiratory and expiratory times (TI and TE) were studied during normoxia (arterial PO2 = 95 Torr) and 48 h of hypoxia (arterial PO2 = 40-50 Torr) in awake intact (n = 8) and carotid body-denervated (CBD; n = 8) ponies. Periodic oscillations were identified by fast-Fourier transformation of breath-by-breath data and quantitated by determining the power ratio of significant periodic oscillations to total power of data sequence. Periodic oscillations of 0.063-0.500 cycles/breath were observed in all parameters during bot...
Muscle characteristics in standardbreds of different ages and sexes. Biopsy samples were taken from the middle gluteal muscle in 107 health Standardbred horses. The horses were separated according to sex and divided into 4 age groups (1, 2, 3 and 4-6 years). The proportion of Type I fibres increased with age (from 16 to 20%), irrespective of sex. The proportions of Type IIA and IIB fibres varied with age and differed between stallions and mares. Type IIA fibres increased in mares from 37 to 47% and in stallions from 40 to 48% and Type IIB fibres decreased from 49 to 34% in mares, and from 43 to 30% in stallions. Mares and stallions did not differ in enzyme acti...
[The laterocranial fascia structures in the upper and forearm and the differences in the insertion of the M. biceps brachii in domestic mammals]. The laterocranial fascia of the upper arm and forearm, as well as aponeurotic relationships of the Musculus biceps brachii were investigated on each of ten forelimbs from horses, cattle and swine. Ten canine biceps were also investigated. Equine and bovine fascia contain elastic components. An as-yet undescribed ligament-like aponeuroses of the laterocranial forearm fascia to the Fossa radialis humeri was seen in all three species studied. The laterocranial fascia of the upper and forearm form a common passage for the Musculi brachialis et extensor carpi radialis. In the case of the horse, the...
Lectin histochemistry of glycoconjugates in horse salivary glands. The glycoconjugate content of major horse salivary glands was investigated by means of horseradish peroxidase-conjugated lectins. Qualitative differences were observed in the terminal sugar residues of secretory glycoproteins and glycoconjugates linked to the apical surface of excretory duct epithelial cells. Mucous acinar cells in mandibular and sublingual glands contained oligosaccharides with D-galactose, alpha- and beta-N-acetylgalactosamine, N-acetylglucosamine and fucose residues, whereas mandibular, sublingual and parotid serous cells contained only oligosaccharides with terminal alpha-...
