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Author Gonzalez-Fernandez, J.M.; Atta, S.E.
Title Facilitated transport of oxygen in the presence of membranes in the diffusion path Type Journal Article
Year (up) 1982 Publication Biophysical Journal Abbreviated Journal Biophys J
Volume 38 Issue 2 Pages 133-141
Keywords Animals; Biological Transport, Active; Cell Membrane/*metabolism; Diffusion; Dogs; Horses; Humans; Kinetics; Mathematics; *Models, Biological; Muscles/*metabolism; Oxygen/*metabolism
Abstract Most of the experimental observations on facilitated transport have been done with millipore filters, and all the theoretical studies have assumed homogeneous spatial properties. In striated muscle there exist membranes that may impede the diffusion of the carrier myoglobin. In this paper a theoretical study is undertaken to analyze the transport in the presence of membranes in the diffusion path. For the numerical computations physiologically relevant values of the parameters were chosen. The numerical results indicate that the presence of membranes tends to decrease the facilitation. For the nonlinear chemical kinetics of the reaction of oxygen with the carrier, this decrement also depends on the location of the membranes. At the higher oxygen concentration side of each membrane the flow of combined oxygen is transferred to the flow of dissolved oxygen. The reverse process occurs at the lower concentration side. Jump discontinuities of the concentration of the oxygen-carrier compound at each membrane are associated with these transfers. The decrement of facilitation is due to the cumulative effect of these jump discontinuities.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0006-3495 ISBN Medium
Area Expedition Conference
Notes PMID:7093418 Approved no
Call Number Equine Behaviour @ team @ Serial 3806
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Author Dyson, H.J.; Beattie, J.K.
Title Spin state and unfolding equilibria of ferricytochrome c in acidic solutions Type Journal Article
Year (up) 1982 Publication The Journal of Biological Chemistry Abbreviated Journal J Biol Chem
Volume 257 Issue 5 Pages 2267-2273
Keywords Animals; *Cytochrome c Group; Electron Spin Resonance Spectroscopy; Heme; Horses; Hydrogen-Ion Concentration; Kinetics; Ligands; Myocardium; Protein Binding; Protein Conformation; Spectrophotometry; Temperature
Abstract Equilibrium, stopped flow, and temperature-jump spectrophotometry have been used to identify processes in the unfolding of ferricytochrome c in acidic aqueous solutions. A relaxation occurring in approximately 100 microseconds involves perturbation of a spin-equilibrium between two folded conformers of the protein with methionine-80 coordinated or dissociated from the heme iron. The protein unfolds more slowly, in milliseconds, with dissociation and protonation of histidine-18. These two transitions appear cooperative in equilibrium measurements at low (0.01 M) ionic strength, but are separated at higher (0.10 M) ionic strength. They are resolved under both conditions in the dynamic measurements. The spin-equilibrium description permits a unified explanation of a number of properties of ferricytochrome c in acidic aqueous solutions.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9258 ISBN Medium
Area Expedition Conference
Notes PMID:6277891 Approved no
Call Number Equine Behaviour @ team @ Serial 3807
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Author Lindsay, F.E.; Burton, F.L.
Title Observational study of “urine testing” in the horse and donkey stallion Type Journal Article
Year (up) 1983 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J
Volume 15 Issue 4 Pages 330-336
Keywords Animals; *Behavior, Animal; Horses/anatomy & histology/*physiology; Male; Nasal Septum; Nose/anatomy & histology; Olfactory Mucosa/physiology; Perissodactyla/*physiology; Sex Attractants/urine; Smell/physiology
Abstract Although “urine testing” is said to enable the male equid to assess the sexual status of the mare, there are no reports in the literature of any detailed study of this behavioural response of the stallion. Behavioural response to conspecific urine was studied in two horse stallions and one donkey stallion. The relevant nasopalatine anatomy is described. Events observed during urine testing included head, neck, lip, jaw, tongue movements, penile changes and nasal secretion. Nasal endoscopy indicated that the source of part of the nasal secretion was the secretory glands of the vomeronasal organ complex. The significance and probable function of these events in urine testing is discussed.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0425-1644 ISBN Medium
Area Expedition Conference
Notes PMID:6641679 Approved no
Call Number refbase @ user @ Serial 1955
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Author Henneke, D.R.; Potter, G.D.; Kreider, J.L.; Yeates, B.F.
Title Relationship between condition score, physical measurements and body fat percentage in mares Type Journal Article
Year (up) 1983 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J
Volume 15 Issue 4 Pages 371-372
Keywords *Adipose Tissue; Animals; Biometry; Body Weight; Female; Heart/anatomy & histology; Horses/anatomy & histology/*physiology; *Reproduction
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0425-1644 ISBN Medium
Area Expedition Conference
Notes PMID:6641685 Approved no
Call Number Equine Behaviour @ team @ Serial 2299
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Author Berger, J.
Title Induced abortion and social factors in wild horses Type Journal Article
Year (up) 1983 Publication Nature Abbreviated Journal Nature
Volume 303 Issue 5912 Pages 59-61
Keywords Abortion, Induced/*veterinary; Abortion, Veterinary/*etiology; Aggression/physiology; Animals; Evolution; Female; Horses/*physiology; Humans; Pregnancy; Sexual Behavior, Animal/*physiology
Abstract Much evidence now suggests that the postnatal killing of young in primates and carnivores, and induced abortions in some rodents, are evolved traits exerting strong selective pressures on adult male and female behaviour. Among ungulates it is perplexing that either no species have developed convergent tactics or that these behaviours are not reported, especially as ungulates have social systems similar to those of members of the above groups. Only in captive horses (Equus caballus) has infant killing been reported. It has been estimated that 40,000 wild horses live in remote areas of the Great Basin Desert of North America (US Department of Interior (Bureau of Land Management), unpublished report), where they occur in harems (females and young) defended by males. Here I present evidence that, rather than killing infants directly, invading males induce abortions in females unprotected by their resident stallions and these females are then inseminated by the new males.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-0836 ISBN Medium
Area Expedition Conference
Notes PMID:6682487 Approved no
Call Number Equine Behaviour @ team @ Serial 4365
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Author Heffner, R.S.; Heffner, H.E.
Title Hearing in large mammals: Horses (Equus caballus) and cattle (Bos taurus) Type Journal Article
Year (up) 1983 Publication Behavioral Neuroscience Abbreviated Journal
Volume 97 Issue 2 Pages 299-309
Keywords auditory range & sensitivity, horses vs cattle
Abstract Determined behavioral audiograms for 3 horses and 2 cows. Horses' hearing ranged from 55 Hz to 33.3 kHz, with a region of best sensitivity from 1 to 16 kHz. Cattle hearing ranged from 23 Hz to 35 kHz, with a well-defined point of best sensitivity at 8 kHz. Of the 2 species, cattle proved to have more acute hearing, with a lowest threshold of –21 db (re 20 μN/m–2) compared with the horses' lowest threshold of 7 db. Comparative analysis of the hearing abilities of these 2 species with those of other mammals provides further support for the relation between interaural distance and high-frequency hearing and between high- and low-frequency hearing. (39 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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Corporate Author Thesis
Publisher American Psychological Association Place of Publication Us Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1939-0084(Electronic);0735-7044(Print) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ 1983-29540-001 Serial 5633
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Author Keiper, R.; Houpt, K.
Title Reproduction in feral horses: an eight-year study Type Journal Article
Year (up) 1984 Publication American journal of veterinary research Abbreviated Journal Am J Vet Res
Volume 45 Issue 5 Pages 991-995
Keywords Abortion, Veterinary/epidemiology; Anestrus; Animal Population Groups/*physiology; Animals; Animals, Wild/*physiology; Birth Rate; Female; Fertility; Horse Diseases/epidemiology; Horses/*physiology; Lactation; Male; Maryland; Pregnancy; *Reproduction; Seasons; Sex Ratio; Virginia
Abstract The reproductive rate and foal survival of the free-ranging ponies on Assateague Island National Seashore were studied for 8 years, 1975 to 1982. Most (52%) of the 86 foals were born in May, 13% were born in April, 22.6% in June, 10.4% in July, and less than 1% in August and September. The mean foaling rate was 57.1 +/- 3.9% and the survival rate was 88.3 +/- 3.6%. Forty-eight colts and 55 fillies were born (sex ratio 53% female). Mares less than 3 years old did not foal and the foaling rate of 3-year-old mares was only 23%, that of 4-year-old mares was 46%, that of 5-year-old mares was 53%, and 6-year-old mares was 69%. The relatively poor reproduction rate was believed to be a consequence of the stress of lactating while carrying a foal when forage quality on the island was low. The hypothesis was supported by the higher reproductive rate (74.4 +/- 2.4%) of the ponies in the Chincoteague National Wildlife Refuge on the southern part of the island. Their foals are weaned and sold in July each year. Despite the low reproductive rate on Assateague Island National Seashore , the number of ponies increased from 43 to 80, a 90% increase in the 8-year period or greater than 10%/yr. There were 24 deaths and 8 dispersals from the study area.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-9645 ISBN Medium
Area Expedition Conference
Notes PMID:6732036 Approved no
Call Number refbase @ user @ Serial 665
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Author Ralston, S.L.
Title Controls of feeding in horses Type Journal Article
Year (up) 1984 Publication Journal of Animal Science Abbreviated Journal J. Anim Sci.
Volume 59 Issue 5 Pages 1354-1361
Keywords Animal Feed; Animals; Digestive Physiology; Energy Metabolism; Feeding Behavior/*physiology; Food Preferences; Horses/*physiology; Oropharynx/physiology; Satiation/physiology; Smell; Taste
Abstract Members of the genus Equus are large, nonruminant herbivores. These animals utilize the products of both enzymatic digestion in the small intestine and bacterial fermentation (volatile fatty acids) in the cecum and large colon as sources of metabolizable energy. Equine animals rely primarily upon oropharyngeal and external stimuli to control the size and duration of an isolated meal. Meal frequency, however, is regulated by stimuli generated by the presence and (or) absorption of nutrients (sugars, fatty acids, protein) in both the large and small intestine plus metabolic cues reflecting body energy stores. The control of feeding in this species reflects its evolutionary development in an environment which selected for consumption of small, frequent meals of a variety of forages.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8812 ISBN Medium
Area Expedition Conference
Notes PMID:6392275 Approved no
Call Number refbase @ user @ Serial 1954
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Author Barton, M.D.; Hughes, K.L.
Title Ecology of Rhodococcus equi Type Journal Article
Year (up) 1984 Publication Veterinary Microbiology Abbreviated Journal Vet Microbiol
Volume 9 Issue 1 Pages 65-76
Keywords Actinomycetales/growth & development/immunology/*isolation & purification; Animal Husbandry; Animals; Antigens, Bacterial/immunology; Artiodactyla/*microbiology; Australia; Digestive System/microbiology; Ecology; Feces/*microbiology; Horses/*microbiology; Hypersensitivity, Delayed; Rabbits/microbiology; *Soil Microbiology
Abstract A selective broth enrichment technique was used to study the distribution of Rhodococcus equi in soil and grazing animals. Rhodococcus equi was isolated from 54% of soils examined and from the gut contents, rectal faeces and dung of all grazing herbivorous species examined. Rhodococcus equi was not isolated from the faeces or dung of penned animals which did not have access to grazing. The isolation rate from dung was much higher than from other samples and this was found to be due to the ability of R. equi to multiply more readily in dung. Delayed hypersensitivity tests were carried out on horses, sheep and cattle, but only horses reacted significantly. The physiological characteristics of R. equi and the nature of its distribution in the environment suggested that R. equi is a soil organism.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0378-1135 ISBN Medium
Area Expedition Conference
Notes PMID:6719819 Approved no
Call Number Equine Behaviour @ team @ Serial 2688
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Author Cho, K.C.; Chan, K.K.
Title Kinetics of cold-induced denaturation of metmyoglobin Type Journal Article
Year (up) 1984 Publication Biochimica et Biophysica Acta (BBA) – Protein Structure and Molecular Enzymology Abbreviated Journal
Volume 786 Issue 1-2 Pages 103-108
Keywords Metmyoglobin denaturation; Temperature jump; Denaturation kinetics; Conformational transformation; (Horse heart)
Abstract Using a slow temperature-jump spectrophotometer, we have studied the kinetics of cold-induced denaturation of metmyoglobin between 0[degree sign]C and 20[degree sign]C at acidic pH. The time-scale of the transition is slow and is of the order of minutes. The results are consistent with the transition's involving a total of three states, native (N), transient intermediate (I) and denatured (D), which are converted from one to the other in that order.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 3978
Permanent link to this record