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31.
Interest exists in the commercial culture of sponges in the Pohnpei region of the Federated States of Micronesia. Sponge culture is appealing in that capital and labor investment is minimal. Investment requirements for a 0.4-ha sponge farm totals $650. Average annual production costs total $500. The sponge farm yields 2,400 sponges per 0.4 ha annually. Annual net returns are approximately $1,744 per 0.134 ha component, beginning in Year 4. Profitability is most sensitive to changes in opportunity wage rate, survival rate, and market price. Commercial sponge farming in Pohnpei shows promise as a source of supplemental income. 相似文献
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In the specialised rearing house for young cattle of all age groups the occurrence of endoparasites was followed. In the age group of 21 to 90 days, 56% of calves aged about 30 days eliminated oocysts of coccidia. On the whole, 49.3% of calves were infested by coccidia, 3% by enterohelminths. 90.3% of calves aged from three to six months were parasitised by coccidia, 7.4% by enterohelminths. Young cattle, aged from 6 to 12 months, were parasitised in 94.6% by coccidia and in 14.1% by enterohelminths. 86.6% of pregnant heifers at the age of 14 to 19 months had coccidia, 7.7% enterohelminths. The total farm capacity was about 950 animals. Throughout the year the number of examined animals amounted to 1,195, out of this number 958 animals, i. e. 80.2%, were infested by coccidia, 55.6% of animals by the species Eimeria bovis, 47.0% by E. zuernii, 43.3% by E. auburnensis, 39.4% by E. ellipsoidalis, 25.2% by E. cylindrica, 13.6% by E. subspherica, 3.1% by E. bukidnonensis, 1.7% by Isospora spp., 0.4% by E. brasiliensis, 0.08% by E. pellita. Enterohelminths were observed only in 96 animals, i. e. in 8.03%. Trichocephalus was found in 3.9% of animals, Cooperia in 2.4%, Ostertagia in 0.6%, Chabertia in 0.4%, Nematodirus in 0.3%, Capillaria in 0.2%, Oesophagostomum in 0.2%, Bunostomum in 0.1% and Trichostrongylus in 0.1%. The highest elimination of oocysts of coccidia was observed in August, January and February, of eggs of enterohelminths from August to October. In all age groups the most frequent was the occurrence of pathogenic species of coccidia. 相似文献
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In this paper an overview of principles involved in nuclear imaging is presented. Nuclear images are picotrial representations of the distribution of systemically administered radiopharmaceuticals. Although many radionuclides are available. 99mTc is the most commonly used radionuclide, either in ionic form (99mTcO4) or bound to other pharmaceuticals. Distribution within the body is by physiologic processes, dependent on the radiopharmaceutical used. Most distribution processes are organ specific rather than disease specific. Scintillation detectors are used to record the activity and disribution of an administered radiopharmaceutical and to create a representative image on film. A rectilinear scanner is an imaging system with a small detector that moves systematically, point by point, over an organ of interest. A gamma (scintillation) camera is an imaging system with a large stationary detector that encompasses a larger field of view. Nuclear imaging provides information based primarily on physiologic principles, and radiography provides infromation based primarily on anatomic or geometric principles. Examples of some scanning procedures are discussed. 相似文献
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Don D. Wanasinghe 《Acta veterinaria Scandinavica》1981,22(1):109
Using a simple in vitro test it was demonstrated that staphylococci, Streptococcus agalactiae, and micrococci, the species of bacteria which are commonly isolated from udder infections, adhered to mammary gland epithelial cells readily and in large numbers. Some strains of organisms which are associated with sporadic outbreaks or occur less commonly, like Str. dysgalactiae and Str. uberis, adhered moderately. Escherichia coli, Klebsiella spp., Corynebacterium pyogenes, C. bovis, Str. bovis, and Str. faecalis, species which are isolated occasionally, adhered poorly. From these studies, it appears that selective adherence of bacteria to the epithelial cells is a factor contributing to the ability of organisms to infect the mammary gland and may, therefore, be considered an important stage in the pathogenesis of bovine mastitis. 相似文献
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Hancock RB Lanz OI Waldron DR Duncan RB Broadstone RV Hendrix PK 《Veterinary surgery : VS》2005,34(3):273-282
OBJECTIVE: To compare the effects of postoperative pain after ovariohysterectomy by harmonic scalpel-assisted laparoscopy (HALO) and traditional ovariohysterectomy (OVH) in dogs. STUDY DESIGN: A randomized, blinded, prospective study. SAMPLE POPULATION: Sixteen, purpose-bred, intact female, Beagle dogs. METHODS: Dogs were divided into 2 groups: Group 1 (8 dogs), which had OVH by HALO, and Group 2 (8 dogs), which had traditional OVH. Physiologic data, abdominal nociceptive threshold scores, and University of Melbourne pain scores (UMPS) were recorded at 2, 6, 12, 24, 48, and 72 hours after surgery. Blood samples for measurement of plasma cortisol, glucose, and creatine phosphokinase (CPK) concentrations were collected at the time of the incision, and 2, 6, 12, 24, 48, and 72 hours after surgery. RESULTS: No significant surgical complications occurred. The HALO mean surgical time was significantly longer (55.7 minutes) than traditional OVH (31.7 minutes). No significant differences were observed between groups for the pain measures of heart rate, respiratory rate, temperature, CPK, and glucose concentrations. The OVH group had significantly higher mean plasma cortisol levels at hour 2 after surgery than the HALO group (P=.0001). The mean UMPS were significantly higher in OVH than the HALO group at all postoperative times (P=.0001). The mean nociceptive threshold measurements revealed significantly higher tolerated palpation pressures in HALO than OVH at all postoperative times, except hour 72 (P=.0002). CONCLUSIONS: Dogs appeared to be in less pain with HALO than OVH. The harmonic scalpel coagulated ovarian and uterine vessels completely with minimal collateral damage to surrounding tissues. CLINICAL RELEVANCE: HALO is a safe alternative to OVH and offers a minimally invasive and less painful method of surgery. 相似文献
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Soft tissue calcification is known to occur in association with chronic renal failure. This soft tissue calcification is frequently recognized microscopically, but infrequently identified radiographically. This paper reviews the role of chronic renal failure in soft tissue calcification and presents three case histories of chronic renal failure in dogs in which soft tissue calcification of the stomach, kidneys, and footpads was detected radiographically. In all three dogs, gastric-wall mineralization was visible radiographically as thin, linear, mineralized densities. Renal mineralization was seen radiographically in two of the dogs. One of the dogs had nodular mineral deposits in the footpads of all feet. Although microscopy confirmed the soft tissue calcification of these and other structures, there was poor correlation between microscopic and radiographic degrees of visceral soft tissue calcification. There was also poor correlation between the degree of calcium and phosphate imbalance and the extent of radiographic evidence of soft tissue calcification. 相似文献
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