Home | [1–10] << 11 12 13 14 15 16 17 18 19 20 >> [21–30] |
![]() |
Houpt, T. R. (1985). The physiological determination of meal size in pigs. Proc Nutr Soc, 44(2), 323–330. |
Aviad, A. D., & Houpt, J. B. (1994). The molecular weight of therapeutic hyaluronan (sodium hyaluronate): how significant is it? J Rheumatol, 21(2), 297–301.
Abstract: Various molecular weight hyaluronic acid (HA) preparations have been injected into joints for the treatment of human and equine osteoarthritis. A therapeutic advantage has been claimed for commercial products with a molecular weight in the range found in normal synovial fluid (SF), compared to lower molecular weight products. But a correlation between molecular weight and efficacy is not borne out by an analysis of the available literature on clinical results. SF viscosity, HA concentration, HA molecular weight and rate of synthesis in joint disease. It is proposed that the beneficial effect of injected HA in joint disease may be due to pharmacological rather than to physical properties.
|
Yokoyama, S., & Radlwimmer, F. B. (1999). The molecular genetics of red and green color vision in mammals. Genetics, 153(2), 919–932.
Abstract: To elucidate the molecular mechanisms of red-green color vision in mammals, we have cloned and sequenced the red and green opsin cDNAs of cat (Felis catus), horse (Equus caballus), gray squirrel (Sciurus carolinensis), white-tailed deer (Odocoileus virginianus), and guinea pig (Cavia porcellus). These opsins were expressed in COS1 cells and reconstituted with 11-cis-retinal. The purified visual pigments of the cat, horse, squirrel, deer, and guinea pig have lambdamax values at 553, 545, 532, 531, and 516 nm, respectively, which are precise to within +/-1 nm. We also regenerated the “true” red pigment of goldfish (Carassius auratus), which has a lambdamax value at 559 +/- 4 nm. Multiple linear regression analyses show that S180A, H197Y, Y277F, T285A, and A308S shift the lambdamax values of the red and green pigments in mammals toward blue by 7, 28, 7, 15, and 16 nm, respectively, and the reverse amino acid changes toward red by the same extents. The additive effects of these amino acid changes fully explain the red-green color vision in a wide range of mammalian species, goldfish, American chameleon (Anolis carolinensis), and pigeon (Columba livia).
Keywords: Amino Acid Sequence; Animals; Base Sequence; COS Cells; Cats; Color Perception/*genetics; DNA Primers; Deer; Dolphins; *Evolution, Molecular; Goats; Guinea Pigs; Horses; Humans; Mammals/*genetics/physiology; Mice; Molecular Sequence Data; Opsin/biosynthesis/chemistry/*genetics; *Phylogeny; Rabbits; Rats; Recombinant Proteins/biosynthesis; Reverse Transcriptase Polymerase Chain Reaction; Sciuridae; Sequence Alignment; Sequence Homology, Amino Acid; Transfection
|
Petter-Puchner, A. H., Froetscher, W., Krametter-Froetscher, R., Lorinson, D., Redl, H., & van Griensven, M. (2007). The long-term neurocompatibility of human fibrin sealant and equine collagen as biomatrices in experimental spinal cord injury. Exp Toxicol Pathol, 58(4), 237–245.
Abstract: INTRODUCTION: While fibrin sealant (FS) and equine collagen (EC) have been used as scaffold materials in experimental spinal cord injury (SCI), questions concerning neurocompatibility still remain. In this study, we assessed potential adverse effects, as well as functional and histological impact of FS and EC in subtotal hemisection of the thoracic spinal cord (SC) in rats. METHODS: 124 male rats were randomly assigned to four main groups (n=31): Sham (SH), Lesion only (L), fibrin sealant (GFS) and equine collagen group (GEC). SH animals received laminectomy only; all other animals underwent subtotal lateral hemisection at T9. Treatment consisted of application of FS or EC into the lesion gap in GFS and GEC, which was left empty in L. GFS, GEC, L and SH were each further divided into 4 subgroups: One subgroup, consisting of 10 rats was subjected to behavioural and reflex testing before surgery and followed up on days 1,7, 14, 21, 28 post op and then sacrificed. Haemalaun or cresyl violet (CV) was used to identify neutrophils in parasagittal cord sections which were obtained on day 1 (n=7). Sections stained for quantification of microglia/macrophages using ED-1 on day 3 (n=7), day 7 (n=7) and day 28 (n=7 out of 10). Additionally, neural filament (NF) staining was chosen to detect axonal regeneration and the length of ingrowth into FS and EC, Luxol blue for myelination, Von Willebrand factor for vascularisation, and glial fibrillary acidic protein (GFAP) staining for detection of astrocytes in glial scars on day 28. RESULTS: No adverse effects were observed in the treatment groups. Compared to L, GFS and GEC performed significantly better in the Basso, Beattie, Bresnahan (BBB) score and hopping responses. Proprioceptive placing was markedly improved in FS and EC compared to L. Axonal regrowth was found in GFS and GEC--the regrowth in the GFS was accompanied by myelination and vascularisation. Glial scarring occurred in all groups. Discussion Both biomatrices improved functional recovery compared to L and no adverse effects were perceived.
Keywords: Animals; Axotomy; Biocompatible Materials/*therapeutic use; Collagen/*therapeutic use; Fibrin Tissue Adhesive/*therapeutic use; Horses; Humans; Immunohistochemistry; Male; Motor Activity/physiology; Nerve Regeneration/*physiology; Rats; Recovery of Function; Spinal Cord/pathology/physiology; Spinal Cord Injuries/pathology/*therapy; Thoracic Vertebrae
|
Malek, E. A. (1971). The life cycle of Gastrodiscus aegyptiacus (Cobbold, 1876) Looss, 1896 (Trematoda: Paramphistomatidae: Gastrodiscinae). J Parasitol, 57(5), 975–979. |
Flauger, B. (2011). The introduction of horses into new social groups with special regard to their stress level. Ph.D. thesis, , .
Abstract: Horses are a highly social species living in complex social systems which should require them to memorise and generalise social experiences and distinguish between familiar and unfamiliar conspecifics. In the main part of my thesis I concentrated on the specific conflict situation of a horse being introduced into a new social group, and investigated its behaviour and stress level. Horses were either introduced (1) immediately, (2) after an observation period, or (3) together with an integration horse after an observation period. Additionally, in the second part of my thesis I arranged several experiments to elaborate additional aspects which could affect the behaviour of horses during introductions. In this study I could describe a simplified method for measuring stress through the analysis of faecal GCMs in horses. An enzyme immunoassay (EIA) for 11-oxoaetiocholanolone using 11-oxoaetiocholanolone-17-CMO: BSA (3?,11-oxo-A EIA) as antigen showed high amounts of immunoreactive substances. The new assay increases the accuracy of the test and lowers the expenses per sample; also storing of samples at room temperature after collection is less critical. This is a big advantage both in the field of wildlife management of equids and in the field of equestrian sports (chapter 1). Comparing the different introduction techniques, the introduction with an integration horse led to significantly less total interactions and lower levels of aggression than the introduction of single horses, both immediately and after several days of observing the new group. Additionally, by observing the behaviour of the horses during everyday sociality I could develop a formula describing the interrelationship between expected aggression level and enclosure size per horse. The curve takes an exponential shape. Starting from a space allowance of 300 m2 and more per horse, the amount of aggressions per hour approaches zero. For the reduction of aggression levels and injury risks in socially kept horses I recommend an enclosure size of at least 300 m2 per horse (chapter 2). I further investigated the stress level of the introduced animals. Horses which were immediately introduced did not show elevated faecal GCMs. In contrast, horses which were introduced after an observation period had slightly elevated values 2 and 3 days after the introduction. For horses introduced together with an integration horse faecal GCMs were significantly above the baseline value on the day of introduction and 1 day after it. These differences between introduction techniques indicate that the introduction event itself is not as stressful as previously assumed. Rather standing together with an integration horse and not being able to integrate immediately into the complete group elicits stress in horses (chapter 3). In the commentary of chapter 4 several studies are discussed which failed to demonstrate social learning in horses. It is argued that they did not consider important aspects which could have an influence, such as the dominance status or the social background of the horses (chapter 4). In chapter 5 a social feeding situation was investigated. The social rank as well as the position of conspecifics affected the feeding strategy of horses. Domestic horses used social cognition and strategic decision making in order to decide where to feed. When possible they tended to return to the same, continuously supplied feeding site and switched to an ?avoidance tendency? in the presence of dominant horses or when another horse was already feeding there (chapter 5). One possibility to recognize group members is through olfactory recognition. In chapter 6 it is shown that horses are able to distinguish their own from their conspecifics? faeces. In addition, they paid most attention to the faeces of those group members from which they received the highest amount of aggressive behaviour (chapter 6). Horses show cognitive abilities because they are able to use humans as local enhancement cues when searching for food, independently of their body posture or gaze consistency when the persons face them. Moreover, they seem to orientate on the attention of familiar persons more than of unfamiliar persons (chapter 7). Altogether, the results of this thesis provide further support for the view that horses show good conflict resolution strategies. They are perfectly able to deal with the conflict situation of being introduced to new group members, and the introduction event itself is not as stressful as previously assumed. It is rather suggested that standing together with an integration horse and not being able to integrate immediately into the complete group elicits stress in horses. All additional experimental set-ups could demonstrate that horses are well capable of social cognition.
Keywords: Pferd; Equiden; Eingliederungstechnik; Integrationspferd; Stress; Cortisol; Endokrine Reaktion; Gruppenhaltung; Verletzungsgefahr; Aggression; Futterplatzwahl; Kot; Geruchssinn; Mensch-Pferd Interaktion; horse; equids; introduction technique; integration horse; stress; cortisol; endocrine response; group housing; injury risk; aggression; feeding decision; faecal sample; olfaction; human-horse interaction
|
Flauger, B., Möstl, E., & Krueger., K. (2012). The introduction of horses into new groups: Social interactions and cortisol release. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: Domestic horses are kept in so-called “fate societies” where they have to deal with frequent mixing. Several studies have evaluated and discussed the aggression level and injury risk during the introduction of horses into new groups, but nothing is known about the endocrine responses and thus if horses experience stress during introduction.
In this study we analysed the efficiency of four approved introduction techniques and evaluated the introduction of 30 horses into 11 different groups. Horses were introduced: 1) immediately, 2) after observing the new group for several days, 3) together with an “integration horse” after several days of observation, or 4) with a mixed strategy. Aggressive as well as positive social behaviour between the introduced horses and the group members were analysed the two hours following the introduction event. In addition, we focussed on the glucocorticoid production of the newcomer horses by measuring faecal cortisol metabolites (FCM) on the day of the introduction as well as the following three days. For the four introduction techniques we found significant differences in the horses’ aggressive and submissive behaviour as well as in their total interactions. The introduction together with an integration horse led to significantly lower levels of aggression and less total interactions than the immediate introduction of single horses. Horses which were introduced immediately or after an observation period showed significantly elevated levels of FCM on the first, second and third day after the introduction. For horses introduced together with an integration horse FCM were already significantly higher on the day of the introduction, indicating a stressful event before the introduction itself. In contrast, FCM levels were always very low when using the mixed technique. In sum, horses have the ability to deal with conflict when they are introduced to new group members. The introduction event itself appears not to be as stressful as previously assumed. Standing together with an “integration horse” on a separate paddock and not being able to integrate immediately into a new group appears to be stressful for the newcomer. Based on the findings of our study we suggest to introduce new horses in group management together with a new group mate, a so-called “integration horse”. This would reduce the number of total social interactions as well as the aggression level. While this technique may be stressful for the newcomer, it lowers aggressive behaviour between the introduced horse and the group members and consequently reduces injury risks. |
Chmel, L., Hasilikova, A., Hrasko, J., & Vlacilikova, A. (1972). The influence of some ecological factors on keratinophilic fungi in the soil. Sabouraudia, 10(1), 26–34.
Keywords: Animals; Arthrodermataceae/growth & development/isolation & purification/metabolism; Carbohydrates; Czechoslovakia; Ecology; Fungi/growth & development/*isolation & purification/metabolism; Hair; Horses; Humic Substances; Humidity; Keratins/metabolism; Microsporum/isolation & purification; Mitosporic Fungi/isolation & purification; Phosphates; Seasons; Soil; *Soil Microbiology; Species Specificity; Temperature; Trichophyton/isolation & purification
|
Malara, L., De Pasquale, A., Ingala, A., & Innella, G. (2008). The influence of management on horse behavioural reactivity in therapeutic riding programs. In IESM 2008.
Abstract: We investigated 8 horses in five therapeutic riding centres situated in San Cataldo (Caltanissetta – I), Nicosia (Catania – II), Pellaro (Reggio Calabria – III), San Gregorio (Catania – IV), Niguarda Hospitals (Milan – V). The managements of the animals were of different typologies: Type 1, Type 2 and Type 3. In type 1 the horses were used for therapeutic riding only. Furthermore intra and interspecific social interactions were not allowed. In type 2 the horses played kinetic activities and made social interactions. In type 3 the horses were free in paddock, as intra and interspecific social interactions were allowed. The centre I, with a management of type 1, housed 1 horse (A1); the centre II, with a management of type 2, housed 1 horse (B2); the centre III, with a management of type 1, housed 1 horse (C1); the centre IV, with a management of type 2, housed 2 horses (D2 and E2); the centre V, with a management of type 3, housed 3 horses (F3, G3 and H3). Breeds of horses were: Anglo-Arab (n°1), Avelignese (n°3), Italian Selle (n°3), draught-horse crossbreed (n°1). They were 2 geldings and 6 females. Their ages ranged from 12 to 23 years. We observed a total of 64 patients affected by different pathologies: autism, motory handicap, blindness and deafness, children“s cerebral paralysis, relational problems, mental deficiency, Down”s syndrome.
The horses" behaviour was observed at rest and during therapeutic activities with these patients. The Heart Rate (HR) was used as physiological parameter for an ethological evaluation, measured by a telemetric heart rate monitor (Polar Horse Trainer). Horses were analysed with a reactivity test for emotional homeostasis evaluation, too. Heart rate values were studied with non parametrical statistical analysis methods. Distinct management typologies provided statistically different basal mean values of heart rate (intergroup and intragroup): Type 1 vs Type 2 (P~0.05) and Type 1 vs Type 3 (P<0.05). The comparison of heart rate during therapeutic activities of diverse management showed the following results: A1 vs B2 (P<0.05), B2 vs C1 (P<0.05), Type 1 vs Type 2 (P<0.01). Different managements, both in the same or different typologies, gave significantly diverse results (A1 vs E2: P~0.05; C1 vs E2: P~0.05; B2 vs E2: P~0.05). This study shows that the statistic differences obtained by therapies with autistic patients derive from management conditions of Type 1. In reactivity test there aren"t any significant differences among the three management typologies. However, we recorded strong variation between medium and maximum values of heart rate, especially in Type 1 and Type 2 of management. These high variations of heart rate indicated fear reaction of the horse to new stimuli. This reaction could lead to dangerous accidents for patients during therapeutic activities. Horses used in therapeutic riding programs must be evaluated before this employment. Horse's behaviour can be assessed by an ethological observation and a reactivity test. Furthermore, the horses must be guaranteed welfare conditions and must live in an environment enriched with sensorial stimuli and respectful of their physiological and ethological needs. Keywords: Management; Horses; Therapeutic Riding; Behaviour; Reactivity
|
Rhodin, M., Johnston, C., Holm, K. R., Wennerstrand, J., & Drevemo, S. (2005). The influence of head and neck position on kinematics of the back in riding horses at the walk and trot. Equine Vet J, 37(1), 7–11.
Abstract: REASONS FOR PERFORMING STUDY: A common opinion among riders and in the literature is that the positioning of the head and neck influences the back of the horse, but this has not yet been measured objectively. OBJECTIVES: To evaluate the effect of head and neck position on the kinematics of the back in riding horses. METHODS: Eight Warmblood riding horses in regular work were studied on a treadmill at walk and trot with the head and neck in 3 different predetermined positions achieved by side reins attached to the bit and to an anticast roller. The 3-dimensional movement of the thoracolumbar spine was measured from the position of skin-fixed markers recorded by infrared videocameras. RESULTS: Head and neck position influenced the movements of the back, especially at the walk. When the head was fixed in a high position at the walk, the flexion-extension movement and lateral bending of the lumbar back, as well as the axial rotation, were significantly reduced when compared to movements with the head free or in a low position. At walk, head and neck position also significantly influenced stride length, which was shortest with the head in a high position. At trot, the stride length was independent of head position. CONCLUSIONS: Restricting and restraining the position and movement of the head and neck alters the movement of the back and stride characteristics. With the head and neck in a high position stride length and flexion and extension of the caudal back were significantly reduced. POTENTIAL RELEVANCE: Use of side reins in training and rehabilitation programmes should be used with an understanding of the possible effects on the horse's back.
|