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排序方式: 共有315条查询结果,搜索用时 250 毫秒
91.
Byeng Ryel Min Kristie McTear Hong Hae Wang Morris Joakin Nar Gurung Frank Abrahamsen Sandra Solaiman Jung Sue Eun Jung Hon Lee Lucas A. Dietz Wayne E. Zeller 《Journal of animal physiology and animal nutrition》2020,104(1):88-100
The aim of the present study was to define whether elevated rumen-undegradable protein (RUP) and tannin-rich peanut skin (PS) supplementation would affect animal growth performance, average daily gain (ADG), blood metabolites, carcass traits associated with lipogenic and immune-related gene expressions in meat goats grazing winter wheat (WW). Thirty-six Kiko-crossbreed male goats at approximately 6 months of age were blocked by body weight (BW; 25.6 ± 1.1 kg) and randomly assigned to one of the four treatments with two replicates based on a 2 × 2 factorial design. Diets contained PS replacing alfalfa meal (ALM), without or with RUP supplementation. Both PS and ALM were incorporated into grain mix portion of the diet and pelletized, with remaining diets fed ad libitum of WW forage for a period of 51 days. Lipogenic genes examined included SCD, ACLY, YWHAZ, PPIA and FABP4, while immune-related genes examined included ACTB (as a control gene), H3F3A, PPIA, IRF3, STAT2, HERC3 and IFIT3 antibody genes. The meat goats on PS-pellet-supplemented group with or without RUP supplementation grew 38.5% faster ADG (p < .001) when compared to control-supplemented group. When goats received PS diet, empty body weight, hot carcass, cold carcass, shoulder, hind shank, rack, loin and fat thickness were greater (p < .05) than control diet. Animals on PS-pellet had higher ACLY, YWHAZ, PPIA and FABP4 gene expression (p < .05) when compared to ALM-pellet control, with RUP by PS-pellet interactions (p < .01). Goats receiving additional RUP supplementation had increased (p < .05) STAT2 gene expression, whereas goats receiving PS-pellet supplementation showed increased STAT2 (p < .05) and a tendency to increase IRF3 (p = .07) gene expressions. In conclusion, the addition of PS-pellet or RUP supplementation has the potential to improve ADG and altered selected lipogenic and immune-related gene expressions. 相似文献
92.
Anthony Weinberg Philip Gibbons Sue V. Briggs Stephen P. Bonser 《Biological conservation》2011,(1):227-233
The process of natural regeneration is critical for sustaining remnant native vegetation and the ecosystem services it supports. We quantified the extent and pattern of Eucalyptus regeneration within remnant vegetation in a fragmented agricultural landscape in south-eastern Australia. Eucalyptus regeneration was absent at 42% of sites. Using an information-theoretic approach, we explored 13 possible models of Eucalyptus regeneration across multiple scales. The explanatory variables in the four models with empirical support (and their summed Akaike weights) were: grazing intensity (1.0), native ground cover (0.99), remnant area (0.83), tenure (0.67), canopy cover (0.21) and vegetation type (0.11). Averaging across these four models we predicted that the probability of Eucalyptus regeneration was highest (0.95) in relatively unmodified remnant native vegetation, that is, remnant vegetation on public land where grazing was light and the understorey was dominated by native plants. In contrast, the predicted probability of Eucalyptus regeneration was lowest (0.12) in small remnants on private land where grazing was heavy. Our results suggest that a large proportion of all remnant native vegetation in this landscape will disappear under existing land management and farming practices. Reducing grazing pressure within intensively grazed remnants appears to be the single most effective management intervention that will mitigate this threat. This will require a shift in conservation priorities away from large, intact remnants where regeneration does not appear to be affected, to poorer quality remnants—often small remnants or scattered trees—where regeneration is typically absent. 相似文献
93.
Sue McIntyre 《Biological conservation》2011,(6):1781-1789
There is a risk that the potential of assisted colonization to contribute to biodiversity conservation will be lost in the storm of controversy that currently surrounds it. This paper describes a low-risk scenario for assisted colonization using plants. Using an analysis of temperate grassy woodlands from Australia, relevant ecosystem attributes are identified which make assisted colonization a sensible strategy, and that may characterize other favorable situations globally. The contributing elements include: a biota adapted to resource conservatism, a naturally connected landscape with component species having wide distributions over a large climatic gradient, current land use unrelated to endogenous disturbance regimes resulting in extensive replacement and modification of the ecosystem over its entire range. Intensive agriculture can create a highly-disturbed and nutrient-enriched landscape matrix, which effectively fragments the species assemblage. Relocation of plant species within and close to their range is not going to create an invasive situation in these landscapes. Candidates for assisted colonization are forbs and interstitial grasses that have persisted over much of their range, but which have declined within that range due to land use impacts. The suggested priority receiving sites would be those with a moderate level of past modifications, now being managed for conservation and with low nutrient status. The proposed use of assisted colonization is a conservative strategy that will build on current conservation practice and greatly improve the prospects for native plants where climate change is superimposed on a fragmented plant community. 相似文献
94.
Kinnison T Lumbis R Orpet H Welsh P Gregory S Baillie S 《Journal of veterinary medical education》2011,38(3):311-318
Interprofessional education (IPE) has received little attention in veterinary education even though members of the veterinary and nursing professions work closely together. The present study investigates veterinary and veterinary nursing students' and practitioners' experiences with interprofessional issues and the potential benefits of IPE. Based on stakeholder consultations, two teaching interventions were modified or developed for use with veterinary and veterinary nursing students: Talking Walls, which aimed to increase individuals' understanding of each other's roles, and an Emergency-Case Role-Play Scenario, which aimed to improve teamwork. These interventions were piloted with volunteer veterinary and veterinary nursing students who were recruited through convenience sampling. A questionnaire (the Readiness for Interprofessional Learning Scale [RIPLS]) was modified for use in veterinary education and used to investigate changes in attitudes toward IPE over time (pre-intervention, immediately post-intervention, and four to five months afterward). The results showed an immediate and significant positive change in attitude after the intervention, highlighting the students' willingness to learn collaboratively, their ability to recognize the benefits of IPE, a decreased sense of professional isolation, and reduced hierarchical views. Although nearly half of the students felt concerned about learning with students from another profession before the intervention, the majority (97%) enjoyed learning together. However, the positive change in attitude was not evident four to five months after the intervention, though attitudes remained above pre-intervention levels. The results of the pilot study were encouraging and emphasize the relevance and importance of veterinary IPE as well as the need for further investigation to explore methods of sustaining a change in attitude over time. 相似文献
95.
Dyson SJ Tranquille CA Collins SN Parkin TD Murray RC 《Veterinary journal (London, England : 1997)》2011,(3):364-371
During a pre-purchase examination (PPE) there is always a debate about how clinical findings of the hoof different from ideal should be interpreted in relation to future lameness risk and/or unsuitability of the horse for the potential purchaser. The objectives of this study were to describe and compare external angular measurements, linear ratios and hoof capsule characteristics of non-lame and lame feet. Photographs of feet from 300 horses with foot pain and 25 non-lame horses were analysed. Hoof wall, heel and coronary band angles and hoof wall length and height, weight-bearing length, coronary band length and height of the coronary band at dorsal and palmar locations were measured and expressed as linear ratios.Mean hoof wall, heel and coronary band angles were larger in lame compared with non-lame feet; only the ratio of dorsal to palmar coronary band heights and the shape of the coronary band were significantly different between lame and non-lame horses. Growth rings were divergent and horn tubules were non-parallel in lameness of >3 months. At a PPE, a larger ratio of dorsal to palmar coronary band heights in one limb may be indicative of previous lameness in that foot. Changes in coronary band shape and divergent growth rings and horn tubules would suggest a longer duration. 相似文献
96.
J. W. Sharp Cleta Sue Bailey R. D. Johnson R. L. Kitchell 《Anatomia, histologia, embryologia》1991,20(3):205-214
The ventral spinal root origin of the radial nerve, its muscle branches, and brachial plexus nerves which supply shoulder and thoracic musculature was determined in the dog. Electrophysiological signal averaging techniques measured evoked potential from specific ventral spinal roots to individual muscle nerves. The entire radial nerve received input from the sixth cervical (C6) through the second thoracic (T2) spinal roots. The most significant (p less than .05) input to triceps brachii came from C8 while the deep ramus of the radial nerve received its largest input from C7. The brachiocephalicus, suprascapular, and subscapular nerves all received their most significant (p less than .05) innervation from C6. Approximately 90% of the evoked potential to the axillary nerve originated from C7. The thoracodorsal nerve received most of its innervation from ventral roots C7 and C8. The lateral thoracic nerve which innervates the cutaneous trunci muscle was supplied by ventral roots C8-T2. Examination of innervation patterns suggests that only modest variation of spinal root input to specific nerves occurred between individual dogs. 相似文献
97.
Osteopenic effects of forelimb immobilisation in horses 总被引:3,自引:0,他引:3
Methods for the non-invasive assessment of bone quality were used to monitor the osteopenia induced by immobilising a forelimb in a cast. These techniques included the measurement of ultrasound velocity, single photon absorptiometry and radiographic photodensitometry. Serial measurements were made before, during and after an eight week period of immobilisation of the left forelimb of four adult standardbreds in a light fibreglass cast which included the foot and extended above the carpus. The measurements continued for 12 weeks after the removal of the cast. The results indicated a trend to decreasing bone strength and mineral content in both forelimbs, with the decreases being greater in the limb with the cast. The values tended to recover slowly after the removal of the cast, then more quickly after the horses returned to the paddock four weeks later. The differences between the limb with the cast and the opposite limb were significant at only a few points of comparison. 相似文献
98.
Nine strains of mycoplasmas were isolated from the lungs of 5 pigs with clinical signs of naturally acquired enzootic pneumonia. Mycoplasma hyopneumoniae was isolated from the lungs of 1 pig and M. hyorhinis from the lungs of 4. An unidentified mycoplasma, which utilized arginine, grew rapidly in broth culture and produced centred colonies on solid medium, was isolated from the lungs of 4 pigs. The pathogenicity of the isolated strain of M. hyopneumoniae was determined by inoculation of pigs from an enzootic pneumonia-free herd. Enzootic pneumonia was produced in the lungs of all 5 pigs inoculated intranasally and intratracheally with broth cultures of the organism isolatied by limit dilution techniques. Enzootic pneumonia was produced in 3 of 6 pigs inoculated intranasally and intratracheally with M. hyopneumoniae purified by the passage of colonies on agar blocks. M. hyopneumoniae was isolated in pure culture from the lungs of all pigs with induced pneumonic lesions. 相似文献
99.
Foster SF 《Journal of Feline Medicine and Surgery》2007,9(2):172-3; author reply 174-5
100.
Henry CJ Downing S Rosenthal RC Klein MK Meleo K Villamil JA Fineman LS McCaw DL Higginbotham ML McMichael J 《American journal of veterinary research》2007,68(11):1246-1251
OBJECTIVE: To evaluate safety and efficacy of LDI-100, a preparation containing human chorionic gonadotropin (hCG) and bacillus Calmette-Guerin (BCG), in the treatment of dogs with mast cell tumors and to compare results with those from a control group receiving single-agent vinblastine. ANIMALS: 95 dogs with measurable grade II or III mast cell tumors. PROCEDURES: Dogs were randomized to receive either LDI-100 (1.35 ng of BCG and 2 units of hCG, SC, q 24 h) or vinblastine (2 mg/m(2), IV, q 1 wk) for 6 weeks. Tumors were measured at baseline and day 42, and dogs were monitored for signs of toxicosis. Clinical performance scores were recorded at each visit. Differences in host factors (sex, weight, and age), clinical performance score, tumor response, and adverse events were analyzed. RESULTS: 46 dogs received LDI-100, and 49 dogs received vinblastine. No significant differences were found between the 2 treatment groups with regard to host factors or clinical performance score. Tumor response (>or=50% reduction) rates were similar between the LDI-100 and vinblastine group (28.6% and 11.7%, respectively). Dogs in the LDI-100 group had significantly less neutropenia than the vinblastine group. CONCLUSIONS AND CLINICAL RELEVANCE: hCG and BCG have immunomodulatory and antitumor effects against a variety of malignancies in humans and dogs. In this study, LDI-100 provided clinical responses comparable to single-agent vinblastine chemotherapy but without myelosuppression. LDI-100 is a promising new agent that should be further investigated for multimodality therapy of mast cell tumors in dogs. 相似文献