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1.
Karen E. Jensen J. Christopher Taylor Robert J. Barry Louis R. D'Abramo D. Allen Davis Stephen A. Watts 《Journal of the World Aquaculture Society》2019,50(3):614-621
Sea urchins produce high‐energy, membrane‐bound fecal pellets that contain residual nutrients and large quantities of microbiota. These egesta are readily consumed by the shrimp, Litopenaeus vannamei. Egesta of the sea urchin, Lytechinus variegatus, were evaluated as a feed supplement or total replacement for a commercial shrimp diet. Shrimp were stocked at 0.49 g ± 0.06 g initial body weight and housed individually in 2.8‐L tanks in a commercial recirculating zebrafish system. Shrimp were assigned to one of six diets: commercial shrimp feed, reference sea urchin feed, collected dried sea urchin egesta, collected wet sea urchin egesta, half ration of shrimp feed and half collected wet sea urchin egesta, and egesta naturally produced by two sea urchins in polyculture. Equivalent dry matter amounts of each diet were proffered to shrimp in each treatment twice daily, except for those that had complete access to natural egesta excreted by sea urchins in polyculture. Sea urchins were proffered a reference sea urchin feed at 2% body weight daily. After 27 days, shrimp proffered collected dried or wet egesta did not differ significantly in percent weight gain and showed the lowest weight gain. The percent weight gain of shrimp fed the commercial shrimp diet did not differ significantly from that of the shrimp fed half commercial shrimp diet and half egesta. The highest weight gain was recorded for those shrimp that consumed the untouched egesta produced by sea urchins in polyculture. These data suggest that consumed egesta have noteworthy nutritional value and therefore would be beneficial to the culture of extractive species in an integrated multitrophic aquaculture system. 相似文献
2.
Barry O. Hughes 《British poultry science》1993,34(3):625-626
Poultry Health and Management: Chickens, Ducks, Turkeys, Geese, Quail, 3rd edn. By David Sainsbury, 1992. 214 pp., illustrated. Oxford, Blackwell Scientific Publications. £17.99. ISBN 0–632–03325–8. 相似文献
3.
Rural depopulation and recent landscape changes in a Mediterranean region: Consequences to the breeding avifauna 总被引:8,自引:0,他引:8
We studied the vegetational and avifaunistic changes following rural depopulation in an area covering 2,600 ha north of Montpellier
(Southern France). The study area is covered by a mosaic of Mediterranean habitats that includes cultivation, grasslands,
shrublands, and woodlands and is representative of the natural features present and of the human usage practiced so far in
this part of the Mediterranean.
We sampled the vegetation and the bird fauna in the same 193 census plots in 1978 and in 1992. At both the habitat and landscape
scales the cover of woody plants increased significantly. Open habitats tend to disappear. As a consequence the abundance
of open-habitat bird species decreased significantly whereas the abundance of forest birds increased significantly. These
changes favor a pool of forest species widespread in western Europe and reduce habitat availability for open habitat and shrubland
species. Many of the latter are Mediterranean species whose distribution in Western Europe could become reduced under current
landscape dynamics. Our observation of more woodlands and their typical birds and of less open habitats and their associated
avifauna is not consistent with the traditional worry shown by the public and the managers about the regression of forests
and woodlands in the Northern Mediterranean as a consequence of fire. 相似文献
4.
Evans EW Harmon BG 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1995,24(4):109-116
Cationic antimicrobial peptides are present throughout the plant and animal kingdoms and bear striking structural and functional similarities across species lines. They provide primitive, nonspecific means of combating a variety of bacteria, fungi, enveloped viruses, and protozoa. Some are also cytotoxic against host cells, including neoplastic cells. Cationic antimicrobial peptides may play various roles in inflammation and tissue repair. Antimicrobial peptides are found in epithelial tissues regularly exposed to microbial attack as well as in cells whose primary function is defense against potential pathogens. They constitute an important part of the nonoxidative antimicrobial arsenal of leukocytes. They are preformed and/or readily synthesized when the cells are stimulated by exposure to pathogens. They exert their effects directly by inserting into membranes of target cells and forming ion channels which increase membrane permeability; however, antimicrobial peptides can also act as opsonins to facilitate phagocytosis. Resistance to defensins is a virulence factor for organisms such as Salmonella sp. The study of cationic antimicrobial peptides is increasing our understanding of innate immunity, inflammation, and the pathogenesis of genetic diseases such as specific granule disease in humans. Therapeutic applications of antimicrobial peptides are currently under investigation. 相似文献
5.
The utility, vehicle required, the time needed for assembly and relocation and the costs associated with six different rainfall simulators were studied. The results can be summarized as follows:
- 1 The simulator designed by Kainz & Eicher (1990) is the least expensive to operate. This simulator also has excellent experimental versatility. Its only restriction is a short slope length.
- 2 The rainfall simulator of Karl & Toldrian (1973) is also inexpensive to operate, but because of disadvantages such as low falling height, wind susceptibility, and the need for more workers than other simulators, it should be used mainly where other simulators are not practical (forests, steep slopes, or long slopes).
- 3 The rainfall simulator of Richter et al. (1988) has limited mobility in the field and is highly susceptible to wind drift. Moreover, its narrow plots do not cover a representative unit of a cultivated field.
- 4 The modified Swanson-type simulator (Auerswald, (1986) is suitable for large plots if a sufficient water supply is available.
- 5 The simulator of Kromer & Vöhringer (1988) has the highest fixed costs, but labour is used efficiently.
- 6 The simulator of Schmidt (1983) can only be considered for stationary use because of its long assembly time. Other disadvantages are narrow plot size and high wind susceptibility.
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9.
Sarah Dodd Maureen Barry Caitlin Grant Adronie Verbrugghe 《Journal of animal physiology and animal nutrition》2021,105(Z2):29-36
A 4-month-old male Old English Sheepdog was presented for evaluation of a raw meat-based homemade diet after a 1-month history of progressive lameness. Marked dietary deficiencies were detected, which included calcium, phosphorus and vitamin D. Hypovitaminosis D and hypocalcaemia were diagnosed by serum analysis. Evidence of severe diffuse osteopenia was noted on survey radiographs. Dual-energy X-ray absorptiometry (DEXA) was used to quantify bone mineral content and density and compare to published reference ranges. The puppy's initial bone mineralization was markedly subnormal, with bone mineral density 66% lower than expected, and bone mineral content 40% lower than expected. Subsequent DEXA scans were performed at intervals during the puppy's recovery to document the rate of bone re-mineralization and guide therapeutic recommendations. Marked improvement was achieved within 4 months through exercise control and feeding of a diet appropriately formulated for large breed puppy growth and development. This report reinforces the necessity of thorough dietary history and highlights the potential for malnutrition in pets fed homemade and raw meat-based diets. Use of DEXA has rarely been reported in clinical cases, yet can be a valuable tool for diagnosing and monitoring cases with abnormal bone mineralization. Further studies using DEXA to track bone mineralization in healthy puppies are encouraged to develop a more robust reference range of bone mineralization in growing dogs of varying sizes, weights and ages. 相似文献
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