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51.
G J Breur C A Zerbe R F Slocombe G A Padgett T D Braden 《Journal of the American Veterinary Medical Association》1989,195(5):606-612
Clinical, radiographic, pathologic, and genetic features of a form of osteochondrodysplasia in 5 related Scottish Deerhound pups from 2 litters were evaluated. All pups appeared to be phenotypically normal at birth. At approximately 4 or 5 weeks, exercise intolerance and retarded growth were observed. Kyphosis, limb deformities, and joint laxity gradually developed. Radiography of the affected pups revealed skeletal changes characterized by abnormalities in long bones and vertebrae, with involvement of epiphyses, growth plates, and metaphyses. Short long bones and vertebrae and irregular and delayed epiphyseal ossification were most noticeable in younger pups; in older pups, bony deformities became more prominent. In skeletally mature dogs, osteopenia and severe deformities were seen. The histologic changes of the growth plate were compatible with a diagnosis of chondrodysplasia. Growth plate chondrocytes contained periodic acid Schiff-positive, diastase-resistant cytoplasmic inclusions. A single autosomal recessive mode of inheritance was suspected. 相似文献
52.
53.
A forest property represents benefits to the owner, the nature of which varies between resident and non-resident owners. Forest
owners’ associations can be considered as an arrangement to increase the benefit from forest ownership by helping the forest
owner to increase profitability. Thus, it can be assumed that associated forest owners value forest property benefits differently
to non-associated owners. This study examines differences between members and non-members, and residents and non-residents,
with respect to how they value the various forest property benefits. Responses from a landholder survey reveal differences
concerning forestry income, maintaining contact with native locality, and keeping up a tradition in forestry. It is concluded
that a challenge for the associations is to develop the organisation in accordance with the forest owners’ dissimilar property
interests. 相似文献
54.
REASONS FOR PERFORMING STUDY: Diagnostic infiltration of local anaesthetic solution is commonly used in cases of equine back pain. Evaluation is subjective and it is not known how local analgesia of the back affects horses without clinical signs of back pain. OBJECTIVES: To evaluate the effect of infiltration of local anaesthetics on the movement of the back in horses without clinical signs of back pain, and to evaluate the usefulness of kinematic studies as an objective and quantitative tool in evaluating local analgesia in clinical practice. METHODS: The kinematics of the back in 10 clinically sound horses were measured on 2 occasions at walk and trot before and after injections with mepivacaine and sodium chloride around the interspinous spaces between T16 and L2. The kinematics were compared between the 2 occasions before injections and before and after each injection. RESULTS: The range of motion (ROM) for dorsoventral flexion-extension (FE) of the back was increased significantly in all measured segments other than T10 at walk, as was lateral bending (LB) at T10, L3 and L5 after injection of mepivacaine. For lateral excursion (LE), total movement increased at all measured segments. At trot the only affected segment was L3, where the injection with mepivacaine decreased the ROM for FE. After injection of sodium chloride the ROM for FE increased at T13 and T17 at walk. Lateral bending and LE were not affected at walk. At trot, LB increased at L3 and L5. CONCLUSIONS AND POTENTIAL RELEVANCE: Diagnostic infiltration of local anaesthetic solution affects the function of the back in clinically sound horses, which must be considered when interpreting the use of this clinical aid in assessing clinical cases of back dysfunction. Kinematics can qualitatively and quantitatively evaluate the effect of local analgesia of the back. 相似文献
55.
David Gunnarsson Gunnar Selstam Yvonne Ridderstr?le Lena Holm Elisabeth Ekstedt Andrzej Madej 《Acta veterinaria Scandinavica》2009,51(1):51
Background
Exposure to xenoestrogens in humans and animals has gained increasing attention due to the effects of these compounds on reproduction. The present study was undertaken to investigate the influence of low-dose dietary phytoestrogen exposure, i.e. a mixture of genistein, daidzein, biochanin A and formononetin, on the establishment of testosterone production during puberty in male goat kids.Methods
Goat kids at the age of 3 months received either a standard diet or a diet supplemented with phytoestrogens (3 - 4 mg/kg/day) for ~3 months. Plasma testosterone and total and free triiodothyronine (T3) concentrations were determined weekly. Testicular levels of testosterone and cAMP were measured at the end of the experiment. Repeated measurement analysis of variance using the MIXED procedure on the generated averages, according to the Statistical Analysis System program package (Release 6.12, 1996, SAS Institute Inc., Cary, NC, USA) was carried out.Results
No significant difference in plasma testosterone concentration between the groups was detected during the first 7 weeks. However, at the age of 5 months (i.e. October 1, week 8) phytoestrogen-treated animals showed significantly higher testosterone concentrations than control animals (37.5 nmol/l vs 19.1 nmol/l). This elevation was preceded by a rise in plasma total T3 that occurred on September 17 (week 6). A slightly higher concentration of free T3 was detected in the phytoestrogen group at the same time point, but it was not until October 8 and 15 (week 9 and 10) that a significant difference was found between the groups. At the termination of the experiment, testicular cAMP levels were significantly lower in goats fed a phytoestrogen-supplemented diet. Phytoestrogen-fed animals also had lower plasma and testicular testosterone concentrations, but these differences were not statistically significant.Conclusion
Our findings suggest that phytoestrogens can stimulate testosterone synthesis during puberty in male goats by increasing the secretion of T3; a hormone known to stimulate Leydig cell steroidogenesis. It is possible that feedback signalling underlies the tendency towards decreased steroid production at the end of the experiment. 相似文献56.
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. 相似文献
57.
Schuberth HJ Dahnke J Leibold W Seyfert HM Zerbe H 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(11-12):464-471
Pathogen associated molecular patterns (PAMPs) and bacterial superantigens have many effects on mononuclear cells (MNC) and macrophages. Influences on neutrophilic granulocytes (PMN), especially by non methylated CpG motifs, gained less attention. Here we investigated whether PAMPs and the superantigen SEA have a direct or indirect influence on the survival rate of bovine PMN. Different CpG motifs, a reverse GpC motif, Lipopolysaccharide (LPS) and SEA did not result in a loss of viability of pure PMN. In the presence of MNC or in vitro generated macrophages (MdM), however, they induced an accelerated dying of PMN. The simultaneous stimulation of MNC/MdM with combinations of CpG motifs and LPS or SEA resulted in an additive or over additive effect: compared to control set ups, only 28-36% of the PMN remained viable in SEA/CpG stimulated MNC/PMN cocultures. Comparing autologous with allogeneic MNC/PMN or MdM/PMN cocultures, it showed up that not only the stimulated MNC or MdM population but also the individual reaction state of the PMN have an influence on the degree of PMN dying. Taken together, CpG motifs and other PAMPs as well as superantigens act in concert to reduce indirectly the viability of neutrophilic granulocytes and hence the functional capacity of an important effector cell population. 相似文献
58.
Jacobsen H Holm P Schmidt M Avery B Greve T Callesen H 《Acta veterinaria Scandinavica》2003,44(1-2):87-95
The general objective of this study was to perform follow-up studies including selected peri- and postnatal characteristics on calves born after transfer of in vitro produced (IVP) embryos vitrified by the 'Open Pulled Straw' (OPS) method. An overall pregnancy rate of 16% after transfer of the OPS-vitrified IVP embryos was achieved and resulted in birth of 9 calves, with 11 AI calves serving as controls. There were no immediate or long-term effects on these calves with respect to birth weight, gestation length, perinatal mortality, growth rate, disease susceptibility and reproductive performance. 相似文献
59.
An endometritis model was used to investigate the influence of degenerative endometrial changes (endometrosis) on functional parameters of uterine neutrophils in the horse. Six hours after intrauterine application of recombinant human interleukin‐8 (rhIL‐8), the uteri of 15 mares were flushed with phosphate‐buffered saline. Quantitative and qualitative flow cytometric assays were then made to determine the absolute numbers, viability, phenotype, generation of reactive oxygen species (ROS), and phagocytic activity of immigrated polymorphonuclear neutrophilic granulocytes (PMN). Recombinant hIL‐8 attracted similarly high numbers of similarly viable PMN into the uteri of mares with or without degenerative endometrial changes. Compared with blood PMN, immigrated uterine neutrophils displayed significantly upregulated expression of CD11a/CD18 (LFA‐1) on uterine PMN whereas major histocompatibility complex class I molecules were expressed at lower densities. The ability to phagocytose opsonized streptococci did not differ between uterine and blood PMN. However, uterine PMN displayed a higher capacity to generate ROS. On average, uterine PMN of mares with degenerative endometrial changes showed phenotypical and functional characteristics similar to those of mares with a histologically healthy endometrium. Therefore, degenerative endometrial changes per se did not reduce the functional capacity of equine uterine neutrophils in mares. 相似文献
60.
Peter Løvendahl Lars Holm Damgaard Karen Thodberg Lotta Rydhmer 《Livestock Production Science》2005,93(1):73-85
This study was designed to estimate genetic variation in aggressive behaviour of sows at mixing, and in maternal ability for the same sows. The study included 835 sows observed for number of mild or severe aggressions performed (F_A1, F_A2), or received (F_R1, F_R2) during 30 min after grouping. Maternal ability was recorded as sows' response to vocalisation from their piglets when these were handled. Maternal behaviour was studied in 1076 sows as a body reaction (MBR) to their piglets being handled after farrowing. Genetic covariances were estimated using a multi-trait animal model, assuming traits to be normally distributed. The heritabilities of performed aggression traits were intermediate (h2 F_A1=0.17, h2 F_A2=0.24), but lower for received aggression (h2 F_R1=0.06, h2 F_R2=0.04), and heritability of maternal behaviour was also low (h2=0.08). Although estimates of genetic correlations had large standard errors, they indicate that less aggressive sows were stronger responding mothers (rg=−0.3). We conclude that performed aggression in sows is a heritable trait, and selection against aggression is possible without offsetting maternal behaviour. 相似文献