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991.
992.
Skin biopsy specimens from 7 dogs with immune-mediated skin diseases diagnosed by routine histology and 5 dogs with other skin diseases were placed in Michel's transport medium for 4 to 9 years. Direct immunofluorescence yielded positive results in tissue samples from 3 dogs with pemphigus foliaceus and 2 dogs with discoid lupus erythematosus. Direct immunofluorescence was not seen in tissue samples from 1 dog with pemphigus foliaceus and 5 dogs with non immune-mediated skin diseases. Direct immunofluorescence was seen in skin biopsy specimens maintained in Michel's medium for 4 to 8 years.  相似文献   
993.
The effects of offspring sex, weight, age, and level of interaction with the dam on responses to weaning were examined to assist in the development of a weaning protocol for alpacas. In the first study, preand post-weaning activities, and weight change over Days -12-0,0-7 and 7-16 with respect to weaning, were recorded for 20 dam-offspring (hembra-cria) pairs aged 81-200 days. Pre-weaning changes in dam and offspring weights were positively related (P<0.05). Although heavier crias tended to be found closer to their dams than lighter crias (P<0.05) no additional effect of age on the dam-offspring relationship was found. Following weaning, cria growth rates were low over Days 0-7 but improved over Days 7-16, and hembra weight change followed the same pattern. Over Days 0-2, grazing and sitting activities of hembras and crias were replaced by standing and walking along paddock fencelines, although by Day 2 fenceline activities had decreased (P<0.05). Crias which were more frequently observed at fencelines had lower post-weaning growth rates (P<0.05). In the second study, pre-weaning sucking behaviour, and weight change over Days -30-0, 0-8 and 8-16 with respect to weaning, were recorded for 19 hembra-cria pairs aged 124-160 days. During 10 hours of observation on Days -5 and -4, the total duration of sucking by individual crias varied from 0-18 minutes, and the mean +/- SEM duration of sucking was 1.94 +/- 0.113 minutes. Cria sucking behaviour was positively related to growth rate prior to and weight at weaning (P<0.05). As in the first study, pre-weaning changes in dam and offspring weights were positively related (P<0.05). Following weaning, growth rates of the crias were depressed and the hembras lost weight over Days 0-8 and 8-16. The changes in growth rate and behaviour in Studies 1 and 2 indicated that weaning can be stressful for hembras and crias. However, there was no evidence from either study that pre-weaning behavioural or physical characteristics were related to the changes.  相似文献   
994.
Controlled tissue expansion using a 100 cc rectangular silicone elastomer expander was performed in the mid-antebrachium and mid-crus of eight adult mixed-breed dogs. Two expander inflation schedules were followed. Group 1 dogs (n = 4) underwent expander inflation using 10 cc sterile saline every other day, and group 2 dogs (n = 4) underwent expander inflation using 15 cc sterile saline every other day until the nominal volume (100 cc) was attained. Significant mean postexpansion increases in skin surface area of 94.1 cm2 (35.9%) and 108.9 cm2 (37.3%) were measured in the antebrachium and crus, respectively (p < .05). In a second procedure, the expanders were removed and skin flaps were developed from the redundant tissue generated during the expansion process. Single pedicle advancement flaps and transposition flaps were used to cover surgically created defects measuring 5 times 10 cm in the antebrachium and cms. Single pedicle advancement flaps consistently measured 10 × 10 cm and could be advanced to cover defects involving one third of the mid-antebrachial or mid-crural circumference. Transposition flaps were rotated up to 170 and the donor site defects were easily closed under minimal or no tension. Complications included an abscess in one dog and seroma formation in four dogs. Differences in success or complication rates between group 1 dogs and group 2 dogs were not observed; an accelerated inflation schedule using 15 cc sterile saline every other day was recommended.  相似文献   
995.
Histomorphometric analysis of bone ingrowth into a porous-coated acetabular component was evaluated in a canine model. A total of nine prostheses were evaluated, 3 at 6 months, 3 at 12 months, and 3 at 24 months after implantation. All implants were grossly stable at the time of retrieval. The mean percentage of bone ingrowth was 12% at 6 months, 24% at 12 months, and 24% at 24 months. Narrow radiolucent lines noted on microradiographs were more evident at the 6 month time period than at the 12 or 24 month time periods. Bone ingrowth into a porous-coated acetabular component in a weight-bearing model may continue beyond the 6 month time period, and early evaluation of bone ingrowth may underestimate final bone ingrowth.  相似文献   
996.
A surgical technique was devised to collect rete testis fluid from 14 mature goats. The tubular portion of the extratesticular rete testis was cannulated where it penetrated the tunica albuginea of the testis under the center of the head of the epididymis. The tip of the cannula was sutured in place in the extratesticular rete testis and the opposite end was passed through the scrotum and into a plastic collection bottle. The bottle was glued to pillow ticking, which was sutured to the scrotum. Continuous flow of rete testis fluid occurred for 0 to 14 days and was usually terminated by a sperm clot in the cannula. The flow rate was 0.59 +/- 0.37 ml/hr.  相似文献   
997.
The influence of two planes of nutrition (unrestricted and 70 per cent restricted during the winter) on skeletal development as illustrated by the metacarpus was studied in 12 red deer stag calves. At approximately three-monthly intervals from January 1978 when the stags were seven months old, until August 1979 when the stags were 26 months old, radiographs of the right metacarpus were taken. From the resultant radiographs, diaphyseal length, diaphyseal breadth, breadth of mineralised bone, cortical bone index and area of mineralised bone were measured. Growth in length was complete by August 1978. There were no differences in length between the unrestricted and restricted stags at that time. Differences in breadth, area and cortical bone index were maintained throughout the study although differences in area of mineralised bone were the only measure significantly different throughout the study. It is considered that the major influence of plane of nutrition on this index of skeletal development in deer is on breadth and thickness of cortical bone, resulting in a weaker bone of the same length in the winter restricted stags.  相似文献   
998.
Intramuscular (i.m.) administration of infectious bronchitis virus (IBV) oil-emulsion vaccine (OEV) to IBV-primed or unprimed chickens resulted in the production of zero or minimal concentrations of IBV-specific IgM in the serum, as measured by enzyme-linked immunosorbent assay of gel chromatography fractions. Live-attenuated infectious bronchitis (IB) vaccine given i.m. or by eyedrop stimulated the production of IBV-specific IgM in similar amounts following inoculation by both routes. These levels were comparable to those found in earlier studies following intranasal inoculation with a virulent strain of IBV and confirm that the detection of IBV-specific IgM is a valuable aid to the diagnosis of recent infection. As expected, administration of live-attenuated IB vaccines i.m. or by eyedrop protected the respiratory tract against challenge with virulent virus 24 days later; however, OEV given i.m. did not.  相似文献   
999.
1000.
Concentrations of IGF-I and IGF-II, and IGF binding proteins (IGFBP) in serum and mammary gland secretions were surveyed during the dry period and early lactation of 30 Holstein cows. Although there was a threefold drop in the concentration of IGF-I in serum from the last week of the dry period to parturition (81 +/- 7 to 24 +/- 3 ng/ml, P less than .01), there was no significant change in serum IGF-II concentration during this period (150 +/- 17 vs 173 +/- 13 ng/ml, P greater than .05). Furthermore, a 57% increase in serum IGF-I was observed from the last week of lactation to the second week of drying off (100 +/- 5 to 157 +/- 8 ng/ml, P less than .05). Changes in serum IGF-II were not observed (126 +/- 11 vs 150 +/- 10 ng/ml, respectively; P greater than .05). Although IGF-I, IGF-II, and IGFBP concentrations in mammary secretions peaked 2 wk before parturition (2.95 +/- 1.1, 1.83 +/- .6, and 7.27 +/- .76 micrograms/ml, respectively), total output/quarter was highest in colostrum (394 +/- 119, 295 +/- 132, and 2,680 +/- 1,967 micrograms/quarter, respectively). Weekly milking of two individual quarters during the dry period did not affect (P greater than .05) IGF-I or IGF-II concentration (ng/ml) or total output (microgram/quarter) and milk yield in colostrum and milk (2 wk and 7 wk) compared with the ipsilateral quarter. The data support the hypothesis that IGF-I may be transported by the mammary gland epithelium. Furthermore, the secretion mechanisms of IGF-I, IGF-II, and IGFBP by the gland may be related to each other.  相似文献   
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