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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.
The primary structure of equine serum amyloid A (SAA) protein. The complete amino acid sequence of equine serum amyloid A (SAA) was elucidated. The protein consists of 110 amino acid residues and contains an 8-amino acid residue insertion tentatively located between positions 69 and 70, as compared with human SAA. Microheterogeneities were detected at positions 16, 44, and 59, compatible with the existence of more than one SAA gene in the horse. This corresponds to the situation in man and mouse. Pronounced homology with SAA from man and several animal species was observed, thus confirming the conserved structure of this acute phase reactant and apoprotei...
Performance of horse-riding helmets in frontal and side impacts. Cases of head injury are reviewed in which riders wearing jockey skull caps have suffered impacts to the front, back or side of their helmets. The design and constructional materials of such helmets are assessed. Impact tests that simulate the accidents confirm the low energy absorption potential of some helmets for lateral impacts. Most pedal or motorcycle helmet designs afford better lateral impact protection.
Functional and ligand binding studies suggest heterogeneity of platelet prostacyclin receptors. 1. This study describes attempts to compare prostacyclin (IP-) receptors in human, pig, horse, rabbit and rat platelets and in circular muscle of human, rabbit and dog mesenteric and pig gastroepiploic arteries. Three stable prostacyclin analogues, iloprost, cicaprost and 6a-carba-prostacyclin (6a-carba-PGI2) and a prostaglandin endoperoxide analogue EP 157 (previously shown to mimic prostacyclin on human platelets) were used. 2. Our main conclusion is that prostacyclin receptors on human, pig and horse platelets are similar in nature, but distinct from those on rabbit and rat platelets. Funct...
Lymphoid nodules in skin biopsies from dogs, cats, and horses with nonneoplastic dermatoses. In a retrospective histopathologic study of nonneoplastic dermatoses, lymphoid nodules were found in 0.3% of 3,408 canine, 5.1% of 469 feline, and 4.5% of 325 equine skin biopsies. In all 3 species, the majority of cases wherein lymphoid nodules were found were diseases of presumed immune-mediated nature. In cats and horses, the majority of cases were also diseases characterized by tissue eosinophilia.
Sequential changes of IgG and antitrypsin in different compartments during the colostral-intestinal transfusion of immunity to the newborn foal. IgG levels and tryptic inhibition were investigated in sequentially collected mare's colostrum and milk, foal serum and urine. The colostral trypsin-inhibitor was "transfused" to the newborn foal by the colostral intestinal route in parallel with IgG. However, the trypsin-inhibitor as a small molecular weight inhibitor became excreted into urine peaking at about 20 hours. The physiological proteinuria in foals during the first 2 days is mostly due to immunoglobulin fragments and colostral-derived trypsin-inhibitor. Analysis of urine for IgG light chains or trypsin inhibitor will therefore reve...
Postprandial serum gastrin concentrations in normal foals. Postprandial gastrin concentrations were assayed in serum samples from a group of six foals at one day, one week, one month and three months of age. Before sampling, each foal was prevented from feeding for 2 h and was then allowed to suck for 15 mins. Blood samples were taken at the start of the meal and at 30 min intervals for the next 3 h. Feeding increased serum gastrin concentrations at one day, one week and one month, with the greatest increases detected at one day. Mean pre-feeding gastrin concentrations were 25.2 +/- 2.3 pg/ml at one day, 22.8 +/- 3.9 pg/ml at one week, 15.2 +/- 2.3 pg...
Retinal vascular patterns in domestic animals. In this paper a morphological study of the retinal vascular patterns in various species of domestic animals is reported. A classification of these patterns into four well-defined groups is described. In the domestic ruminants, pigs and carnivores the retina contains a compact plexus of blood vessels located in the major part of the light-sensitive portion of the retina (euangiotic or holangiotic pattern). In other domestic animals blood vessels are present only in a smaller part of the retina. In the rabbit, vessels are confined to a broad horizontal band coincident with the area of dispersion...
Comparative toxicity of the horse eosinophil peroxidase-H2O2-halide system and granule basic proteins. Stimulated eosinophils release cytotoxic granule constituents, including eosinophil peroxidase (EPO) and a group of granule basic proteins (GBP). EPO reacts with H2O2 formed by the respiratory burst and a halide to form cytotoxic oxidants. The relative potency of the EPO-H2O2-halide system and the GBP is considered here. Horse eosinophils were induced to degranulate, the degranulation products were separated by chromatography on Sephadex G-50 and comparable volumes of the column fractions were tested for toxicity to Escherichia coli and the schistosomula of Schistosoma mansoni in the presence ...
Structure of the alpha 1 subunit of horse Na,K-ATPase gene. Genomic DNA for Na,K-ATPase alpha 1 subunit was obtained from libraries of horse kidney genomic DNA in Charon 4A and in EMBL3 bacteriophages by screening with the full sized cDNA probe of the alpha 1 subunit of rat Na,K-ATPase as probe. The gene spans 30 kb and consists of 23 exons and 22 intervening sequences. Intron-exon boundaries were analyzed. The protein-coding nucleotide sequence encodes 1016 amino acids with an Mr of 112,264. The putative amino acid sequence of horse alpha 1 is 96-97% homologous to those of other mammalian species.
Comparison of four screening techniques for the diagnosis of equine neonatal hypogammaglobulinemia. Using radial immunodiffusion as a standard, 4 screening techniques for detection of failure of passive transfer in equine neonates were compared for sensitivity, specificity, positive and negative predictive values, efficiency, and cost. The techniques compared were latex agglutination test, membrane filter ELISA, dipstick ELISA, and glutaraldehyde coagulation (GC) test. Test results of 50 serum samples from foals 24 to 60 hours old revealed consistently highest accuracy in the GC test at IgG concentrations of 400 and 800 mg/dl, and lowest cost per test, using the GC test. Two hundred fifty-th...
DNA polymorphism analysis of hereditary multiple exostoses in horses. Genomic DNA polymorphisms obtained by restriction fragment-length polymorphism from healthy horses and horses with hereditary multiple exostoses were analyzed. These DNA were digested by 12 restriction enzymes and were hybridized against 6 isotopically labeled oncogene probes. Hybridization was not detected with the viral oncogene, v-ras, which indicated this oncogene was absent in the equine genome. Oncogenes (c-raf-1, c-fes, c-myb, c-myc, and c-sis) were present and had similar hybridization patterns and signal intensities in DNA from healthy horses and horses with hereditary multiple exosto...
The variety of sterility and gradual progression to fertility in hybrids of the horse and donkey. Generally speaking, the majority of F1 hybrids between the horse and donkey are sterile and do conform to the hypothesis of gametogenic breakdown. The results of our own research, nevertheless, lead us to conclude that there is variability in degree of sterility and fertility for both F1 and B1 individuals, with a gradual advance from sterility to fertility being seen. This is the subject we will discuss from the point of view of oestrus, ovulation, mating, pregnancy, spermatogenesis, endocrine activity, isozymes and karyotypic analysis in this paper.
In-vitro plasma protein binding of propafenone and protein profile in eight mammalian species. The protein binding of propafenone in vitro was assessed in plasma of mouse, rat, rabbit, dog, sheep, man, cow, and horse at two concentration levels. In all species and at both concentrations propafenone was found highly bound (86-99%) to plasma proteins. No significant relationship was found between free propafenone and the plasma protein fractions. A concentration-dependency was seen in plasma of mouse, sheep, man, and horse, in which the free fraction of propafenone became larger on raising the concentration. Qualitative and quantitative differences were observed in the protein plasma prof...
Gastric ulcers in horses: a comparison of endoscopic findings in horses with and without clinical signs. Gastroendoscopic examinations were performed on 187 horses, ranging from one to 24 years. Eighty-seven horses had clinical problems including chronic, recurrent colic for seven or more days (25), one or more episodes of colic within the previous seven days (13), or acute colic (10), diminished appetite (53), poor bodily condition (40), and/or chronic diarrhoea (9). One hundred horses that had no signs of gastrointestinal problems were examined as part of a gastroendoscopic survey. Lesions observed in the squamous fundus, squamous mucosa adjacent to the margo plicatus along the greater curvatur...
Regional gastric pH measurement in horses and foals. The pH of the gastric mucosal surface and gastric content was measured in 18 foals (mean age: 20 days) and 27 horses (mean age: 2.9 years) with a pH electrode passed through an endoscope biopsy channel. A reference electrode was attached to a shaved area on the neck. pH Measurements of the gastric mucosal surface at the dorsal squamous fundus (SF), squamous mucosa adjacent to the margo plicatus (MP), glandular fundus (GF) and the fluid or feed contents of the stomach were recorded in duplicate for each animal. In adult horses, the SF pH was greatest (5.46 +/- 1.82), with a decreasing pH ventra...
Comparison of detomidine, butorphanol, flunixin meglumine and xylazine in clinical cases of equine colic. Detomidine hydrochloride, butorphanol tartrate, flunixin meglumine and xylazine hydrochloride were evaluated in a blind multi-centre clinical trial in 152 horses with abdominal pain. The drugs were administered as follows: detomidine 20 or 40 micrograms/kg bodyweight (bwt); butorphanol 0.1 mg/kg bwt; flunixin meglumine 1.0 mg/kg bwt; xylazine hydrochloride 0.5 mg/kg bwt. Each centre compared responses to the two doses of detomidine with those to one of the other analgesics. The drugs were administered intravenously (i.v.) after clinical assessment of the degree of sweating, kicking, pawing, he...
Correlative morphometry and morphology of normal equine intestinal mucosa and comparison after adaptation to extensive large colon resection. Light microscopy, morphometry and scanning electron microscopy (SEM) were used to examine the mucosal morphology of seven intestinal specimens (three from the small intestine and four from the large intestine) from two horses not subjected to surgery and three horses one year after sham-operation for colon resection. Qualitative and quantitative evaluation revealed similar morphology for all horses except that the unoperated horses had significantly (P < 0.05) fewer goblet cells in the crypts of the large intestine. In the small intestine, SEM demonstrated that villus shape varied and range...
Comparison of age, sex, breed, history and management in 229 horses with colic. A study, at a university in south eastern USA, aimed to determine whether age, sex, breed, management and history differed in colic cases. A detailed history was obtained for 229 horses between January 1987 and June 1988. Causes for colic determined by clinical examination, exploratory laparotomy and/or necropsy included: gastric rupture (GR, 6); ileal impaction (II, 17); small intestinal strangulating obstruction (SIO, 22); proximal enteritis (PE, 16); transient small intestinal distension (TSID, 18); large colon displacement (LCD, 52); large colon impaction (LCI, 34); colitis (8); small colo...
Resistance to gentamicin and amikacin of gram-negative organisms isolated from horses. Resistance of gram-negative bacteria to gentamicin has become an increasingly common problem among clinical isolates from human beings. Susceptibility of isolates from horses to gentamicin and amikacin was evaluated for the period from July, 1983 to June, 1985. All isolates of Escherichia coli, and species of Enterobacter, Klebsiella, Proteus, and Pseudomonas examined were susceptible to amikacin, except 2 of the 46 Pseudomonas isolates. In contrast, 13 to 50% of isolates were resistant to gentamicin. Escherichia coli, and Klebsiella, Proteus, and Enterobacter species isolates were highly sign...
Androgen synthesis and aromatization by equine corpus luteum microsomes. Whereas mare corpus luteum does not produce androgens or estrogens in vivo, the incubation of mare corpus luteum microsomes with progesterone and NADPH resulted in 17 alpha-hydroxyprogesterone and estrogen production with a small yield of androstenedione. In the presence of an aromatase inhibitor (4-hydroxyandrostenedione), 17 alpha-hydroxyprogesterone and androstenedione were accumulated. Aromatization of testosterone and androstenedione occurred via stereospecific loss of the 1 beta, 2 beta hydrogen atoms and was inhibited by MgCl2, KCl, and EDTA. The Km of estrogen synthetase from equine co...
Temporal appearance of seasonal changes in numbers of Sertoli cells, Leydig cells, and germ cells in stallions. The temporal appearance of seasonal changes in numbers of Leydig, Sertoli, and germ cells was evaluated to determine if seasonally increased daily spermatozoan production might be preceded by changes in numbers of either of two somatic testicular cells. A significant increase in numbers of spermatogonia and Sertoli cells preceded the significant increase in number of Leydig cells in the approaching breeding season. Seasonal changes in parenchymal weight and in numbers of Sertoli cells, Leydig cells, and germ cells were maximal in May and June. Numbers of A or B spermatogonia in June were 2.4 t...
Evolution of the ECG from Spanish bred foals during the post natal stage. A study of electrocardiograms recorded from foals during the first two weeks of life has been made in order to detect any changes of the cardiac activation and recuperation processes during this period. A stepwise discriminant analysis revealed significant differences between the first and second week of age, fundamentally on the basis of the T and P wave amplitudes which gave the lowest values at 14 days, and on the PQ segment duration that showed the highest values at the same age.
Effects of phenylbutazone on glucose tolerance and on secretion of insulin in healthy geldings. The effect of phenylbutazone (4.4 mg/kg of body weight, IV, q 24 h, for 5 days) on glucose tolerance and on secretion of insulin in 6 healthy geldings was determined. Phenylbutazone significantly lowered fasting concentrations of glucose in plasma but did not significantly change the concentration of insulin in serum. There was no significant effect of phenylbutazone on glucose tolerance, on secretion of insulin, or on the area under the insulin/glucose ratio vs time curve in healthy geldings, as determined by paired t test analysis.
[A comparison of suturing and non-suturing of scrotal wounds following castration in stallions]. It was found that wound infections may be considerably reduced when castration is carried out under strictly aseptic conditions. In this clinical review, healing of the wound following castration with and without closure of the scrotal wounds is compared. All castrations were performed under similar aseptic conditions, general anaesthesia having been produced in the recumbent stallion. The results do not show that there is a significant difference in the appearance of wound infections in scrotal wounds which are closed and those which are left completely open. On the basis of both papers and t...
Observations on the occurrence of five species of Gasterophilus larvae in free-ranging horses in Umbria, central Italy. Comparative data collected over 4 years show the most frequent species of Gasterophilus infesting free-ranging horses in Umbria (Central Italy) to be G. intestinalis (93.8%), G. nasalis (76.5%) and G. inermis (71%). G. pecorum and G. haemorrhoidalis were less frequent and appeared in 39.3 and 10.8% of the animals, respectively. For each of the 5 species, the duration of gastric and enteric lesions, the average numbers of larvae isolated throughout the year and the probable duration of oral lesions were discussed.
Twin embryos in mares. I: From ovulation to fixation. Recent findings on the origin and development of twins from ovulation (Day 0) to fixation (mean: Day 16) are reviewed. Available data show that almost all twins originate from multiple ovulations. Results of recent ultrasound studies indicate that the number of days between double ovulations does not affect the conception rate per ovum or embryo survival during the first 16 days after each ovulation. Embryo reduction is the natural elimination of excess embryos so that only one embryo enters the foetal stage. In two studies, embryo reduction before or on the day of fixation was not considered ...
Comparative ventilation and gas exchange in the horse and the cow. Ventilation and gas exchange were studied in healthy, adult horses and cows, two large species with different lung structures and different breathing patterns. The oxygen uptake (VO2), carbon dioxide output (VCO2), respiratory rate (fR), minute ventilation (VE), alveolar ventilation (VA), alveolar oxygen pressure (PAO2), and VE/VO2 ratio were higher in the cows, while the tidal volume (VT) and physiological dead space (VD) were larger in the horses. The arterial blood gases, alveolar-arterial oxygen pressure difference (PAO2-PaO2) and VD/VT ratio did not differ between the two species. The hig...
