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1.
Matthew M. Nelson Ben D. Mooney Peter D. Nichols Charles E Phleger Greg G. Smith Piers Hart Arthur J. Ritar 《Journal of the World Aquaculture Society》2002,33(2):146-157
The lipid class and fatty acid (FA) composition of juvenile Artemia fed continuously on four diets—the microalga Tetraselmis suecica , a mix of oat bran-wheat germ-lecithin (OWL), OwL-eicosapentaenoic acid (EPA), and OWL-EPA-arachidonic acid (AA)—were examined over a 9-d experiment in an attempt to approximate the FA profile of phyllosoma larvae of wild southern rock lobster Jasus edwardrii . The main difference in lipid class composition of Artemia fed the four diets was the relative level of polar lipid (PL) and triacylglycerol (TAG). By day 9, the algal-fed Artemia were highest in PL (95% of total lipid) and lowest in TAG (2%), whereas the remaining diets resulted in Artemia with 16–30% PL and 41–82% TAG. After 2 d, the relative FA composition of all Artemia treatments closely reflected those of the diets, with no marked change after further feeding (to day 9). In terms of the content of essential polyunsaturated fatty acids (PUFA), by day 5 Artemia fed: 1) with the algal diet contained 7 mg/g FA dry mass (0.3% DHA, 6.3% EPA, 3.4% AA of total FA); 2) with the OWL diet contained 3 mg/g (0.3% DHA, 0.9% EPA, 0.7% AA); 3) with the OWL-EPA diet contained 55 mg/g (6.2% DHA, 11.6% EPA, 1.1% AA); and 4) with the OWL-EPA-AA contained 83 mg/g (3.8% DHA, 7.5% EPA, 17.4% AA). The PUFA profiles of Artemia using the OWL-oil diets were similar to wild rock lobster phyllmmata, although levels of doco-sahexaenoic acid (DHA) were lower (10% DHA) than in J. edwardsii larvae. On the basis of PUFA composition data alone, the results suggest the suitability of the OWL-oil mixed diets for consideration for feeding to Artemia used in the culture of southern rock lobster larvae, particularly if the level of DHA can be further enhanced. 相似文献
2.
G M Peavy E J Walder J S Nelson M Rosenberg 《Journal of the American Veterinary Medical Association》2001,219(8):1094-7, 1073
One dog and 2 cats were evaluated because of multiple progressively enlarging cutaneous vascular plaques. Biopsies were performed and revealed small well-circumscribed dermal nodules of dilated fully enclosed blood-filled spaces lined by single layers of endothelial cells aligned on thin fibrous walls, with minimal mitotic activity. A diagnosis of cutaneous angiomatosis was made in all 3 animals. Cutaneous angiomatosis is a progressive proliferative lesion of vascular tissue involving the dermis and subcutaneous tissues of dogs and cats. Lasers of selected wavelengths have been used to induce photothermal coagulation of hemoglobin-containing cutaneous lesions in humans; argon-pumped dye and neodymium:yttrium-aluminum-garnet lasers were used to treat the cutaneous lesions in the animals of this report. Laser treatment may provide an alternative to wide surgical resection or limb amputation for management of this condition in veterinary patients. 相似文献
3.
Samuel Jakovljevic DVM MSc DVR Nicole MacLaren DVM 《Veterinary radiology & ultrasound》1995,36(5):457-457
4.
P Litwak W V Lumb A W Nelson S Young J P Bowman 《American journal of veterinary research》1978,39(9):1519-1524
Removal of the 2nd or 3rd lumbar vertebrae (or both) has been accomplished in the subhuman primate (Macaca mulatta). Variations between this animal and the dog in posture, vertebral column anatomy, and spinal cord blood supply made no apparent difference in the results when compared with those in previous experiments. All macaques were able to clinb and to use their hind legs in a normal manner within 3 days after surgical operation. Once hair had regrown over the surgical incision, persons not familiar with the animals were not able to identify the animals that had undergone surgical operation. If a single vertebra was removed, use of spinous process and a single vertebral body plate was sufficient to stabilize the vertebral column. Except for 1 rhesus macaque whose spinous process plates were removed 20 days after the operation, vertebral columns of macaques (n = 3) that underwent single spondylectomy healed in nearly normal alignment. With the removal of 2 lumbar vertebrae, the previously described stabilization procedure was not sufficient to prevent kyphotic deformity of the vertebral column. Spinous process plates from 1 macaque were removed after 64 days. However, all these macaques (n = 3) could climb and use their legs as well as others in the colony. 相似文献
5.
1. The mechanical behaviour of the egg shell of the domestic fowl was investigated by cutting strips from the shell and testing the flection either in a four‐point load test or in a cantilever beam test.
2. It was found that moisture content, temperature and load rate have important effects on shell properties ; both the strength and stiffness of the shell are greater in snapping‐inward tests than in snapping‐outward tests; residual stress exists in the egg shell; the correlation between failure moment and shell thickness was highly significant, on average about 0.9, and was dependent on the spread in the thickness data.
3. Estimates were made of the ultimate strength and Young's modulus of egg shell material and it is concluded that a substantial size effect exists in the egg shell. 相似文献
6.
Regg Neiger Nicole Nelson Dale Miskimins Jim Caster Larry Caster 《Journal of veterinary diagnostic investigation》2004,16(5):436-438
A ranch in central South Dakota had a number of dead calves because of arsenic poisoning. The clinical picture included diarrhea, central nervous system signs, and death. Gross necropsy findings included adequate body fat, stomachs full of normal-appearing ingesta, and large amounts of greenish brown watery fluid in the intestine and colon. Microscopically there was severe lymphoid tissue necrosis in the mesenteric lymph nodes and gut-associated lymphoid tissue. Chemical analysis of kidneys showed no significant amounts of lead; however, kidney arsenic concentrations were 25 to 44 ppm. The source was a small pile of Paris Green (common name for cupric acetoarsenite) found in an old dump site in the pasture. 相似文献
7.
Genotypic Variation for Tolerance to Transient Drought During the Reproductive Phase of Brassica rapa
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Y. M. Guo N. C. Turner S. Chen M. N. Nelson K. H. M. Siddique W. A. Cowling 《Journal of Agronomy and Crop Science》2015,201(4):267-279
Brassica rapa L. is a genetically diverse parent species of the allotetraploid species, oilseed rape (B. napus) and a potential source of drought tolerance for B. napus. We examined the effect of a 13‐day drought stress period during the early reproductive phase, relative to a well‐watered (WW) control, on subsequent growth and development in nine accessions of B. rapa and one accession of Brassica juncea selected for their wide morphological and genetic diversity. We measured leaf water potential, stomatal conductance, water use, and leaf and bud temperatures during the stress period and aboveground dry weight of total biomass at maturity. Dry weight of seeds and reproductive tissue were not useful measures of drought tolerance due to self‐incompatibility in B. rapa. The relative total biomass (used as the measure of drought tolerance in this study) of the 10 accessions exposed to drought stress ranged from 47 % to 117 % of the WW treatment and was negatively correlated with leaf‐to‐air and bud‐to‐air temperature difference when averaged across the 13‐day stress period. Two wild‐type (B. rapa ssp. sylvestris) accessions had higher relative total and non‐reproductive biomass at maturity and cooler leaves and buds than other types. We conclude that considerable genotypic variation for drought tolerance exists in B. rapa and cooler leaves and buds during a transient drought stress in the early reproductive phase may be a useful screening tool for drought tolerance. 相似文献
8.
Carlos Yanes‐Roca Mayra E. Toledo‐Cuevas Lizbeth J. Sánchez Ana Born‐Torrijos Nicole Rhody Kevan L. Main 《Journal of the World Aquaculture Society》2018,49(3):612-624
Black snook, Centropomus nigrescens, have been identified as a promising candidate for aquaculture although, like many of the Centropomid species, high mortality associated with early larval stages presents a significant bottleneck to their commercialization. The digestive capacity of black snook larvae throughout the first 37 d after hatch (d.a.h.) was evaluated by quantifying digestive enzyme activities using biochemical techniques. Results showed that black snook larvae have alkaline proteases at hatching, which are known to be important during the first days of feeding for digestion. Toward the end of the study, acid proteases concentration increased (37 d.a.h.). Enzymes for lipid digestion, pancreatic lipase and bile salt‐activated lipase, were already present in the larvae before exogenous feeding commenced, and their activity increased with age and growth (length). Intracellular digestion, measured as the activity of leucine‐alanine peptidase, was high early on (5 d.a.h.) and decreased as development progressed (next 32 d). In contrast, alkaline phosphatase activity was lowest at first feeding and subsequently increased with age. Overall patterns in enzyme activity suggest the possibility of live feed weaning before 32 d.a.h. if artificial diets can be properly balanced. 相似文献
9.
10.
Tatiana C. Weisbrod Ramiro Isaza Carolyn Cray Laurie Adler Nicole I. Stacy 《The Veterinary quarterly》2021,41(1):30
Unique features of elephant hematology are known challenges in analytical methodology like two types of monocytes typical for members of the Order Afrotheria and platelet counts of the comparatively small elephant platelet. To investigate WBC differential and platelet data generated by an impedance-based hematology analyzer without availability of validated species-specific software for recognition of elephant WBCs and platelets, compared to manual blood film review. Blood samples preserved in ethylenediaminetetraacetic acid (EDTA) of 50 elephants (n = 35 Elephas maximus and n = 15 Loxodonta africana) were used. A Mann-Whitney test for independent samples was used to compare parameters between methods and agreement was tested using Bland-Altman bias plots. All hematological variables, including absolute numbers of heterophils, lymphocytes, monocytes, eosinophils, basophils, and platelets, were significantly different (p < 0.0001) between both methods of analysis, and there was no agreement using Bland-Altman bias plots. Manual review consistently produced higher heterophil and monocyte counts as well as platelet estimates, while the automated analyzer produced higher lymphocyte, eosinophil, and basophil counts. The hematology analyzer did not properly differentiate elephant lymphocytes and monocytes, and did not accurately count elephant platelets. These findings emphasize the importance of manual blood film review as part of elephant complete blood counts in both clinical and research settings and as a basis for the development of hematological reference intervals. 相似文献