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1.
A 57‐day feeding trial was designed to assess the potential of corn gluten meal (CGM) as a plant protein source in practical feeds for white shrimp Litopenaeus vannamei. Five experimental diets providing 350 g kg?1 protein and 110 g kg?1 lipid were prepared, where 0%, 25%, 50%, 75% and 100% of fishmeal (FM) protein was substituted by protein from CGM. The results showed that partial or complete replacement of FM with CGM did not affect survival. The growth of the shrimp declined as the levels of CGM increased, diets containing CGM showing a significantly lower final weight (3.2–5.9 g) and specific growth rates (1.7–2.7% per day) compared to those fed on the diet with 0 CGM (7.1 g and 3.0% per day). Feed conversion ratio was also significantly affected by CGM level. The inclusion of CGM resulted in a statistical decrease in the apparent digestibility (AD) of dry matter from 77.9% to 66.0% and in AD of protein from 80.5% to 52.0%, of feed. The AD of amino acids, with the exception of lysine, declined with the dietary incorporation of CGM. In summary, reduced palatability, low protein digestibility and a deficiency of lysine and methionine seem to be the major reasons behind a depressed growth in shrimp fed on CGM protein‐based diets.  相似文献   
2.
During the Galileo probe's descent through Jupiter's atmosphere, under the ionosphere, the lightning and radio emission detector measured radio frequency signals at levels significantly above the probe's electromagnetic noise. The signal strengths at 3 and 15 kilohertz were relatively large at the beginning of the descent, decreased with depth to a pressure level of about 5 bars, and then increased slowly until the end of the mission. The 15-kilohertz signals show arrival direction anisotropies. Measurements of radio frequency wave forms show that the probe passed through an atmospheric region that did not support lightning within at least 100 kilometers and more likely a few thousand kilometers of the descent trajectory. The apparent opacity of the jovian atmosphere increases sharply at pressures greater than about 4 bars.  相似文献   
3.
Clinical and anatomical features of lymphosarcoma in 118 cats   总被引:2,自引:0,他引:2  
Objective To determine patients' characteristics and anatomical distribution of lesions in cats with lymphosarcoma. Design Prospective multi-institutional study of naturally occurring feline lymphosarcoma. Methods Veterinarians in Sydney were provided with free diagnostic laboratory services for suspect cases of feline lym-phosarcoma. Lymphosarcoma was diagnosed based on physical findings, radiographic and/or ultrasonographic images and results of cytological or histopathological examination. When owners were not interested in pursuing an antemortem diagnosis, suspect cases were collected for necropsy. Patients' characteristics and physical findings were recorded. A modified scheme for anatomical classification of lesions was devised including a ‘mixed’ category for cases which involved two or more anatomical forms. Results One hundred and eighteen cases were accrued over an 18 month period. The median age was 120 months and range 5 to 212 months. Age distribution was bimodal, with a small peak for cats less than 24 months, and a normal distribution centred on 97 to 120 months. Eighty cats were domestic crossbreds, 22 were Siamese or Oriental cats (including crosses), 6 were Burmese, 5 were purebred longhairs and the remaining 5 were one of a number of purebred shorthaired breeds. In comparison to 1017 consecutive cases admitted to our hospital for conditions other than lymphosarcoma, Siamese/Oriental cats were over-represented amongst lymphosarcoma cases (P = 0.0006). Male cats were also over-represented, accounting for 72 of 118 cases (P = 0.05). Abdominal lymphosarcoma was the most common anatomical form (43 cats), followed by mixed (39), nodal (20), mediastinal (9) and atypical (involving non-lymphoid organs, 7) forms. When analysed for specific organ involvement, 29 (25%) had mediastinal involvement, 71 (60%) had abdominal involvement including 60 (51%) with involvement of the intestinal tract and/or mesenteric lymph nodes and 36 (31%) with bilateral renal involvement, and 47 (40%) had peripheral lymph node involvement. No case of primary lymphoid leukaemia was identified. A noticeable subgroup of cats younger than 24 months had involvement of the anterior mediastinum with or without concurrent enlargement of cervical or axillary lymph nodes; Siamese/Oriental cats were over-represented in this subgroup. Among cases with nodal involvement, lymph nodes of the head and neck were frequently involved, mandibular nodes most commonly, followed by superficial cervical nodes. In seven cases a solitary node was affected. Conclusions Compared with similar surveys overseas, our cats were older and male cats were over-represented. There was a notable subgroup of young cats with mediastinal involvement. Siamese/Oriental cats were over-represented in this subgroup as well as in the larger population of cats with lymphosarcoma. Compared with overseas surveys, renal involvement, mixed cases and atypical cases (including nasal lymphosarcoma) were more common. A new subcategory of nodal lymphosarcoma, with involvement restricted to node(s) of head and neck, was identified.  相似文献   
4.
Objective To measure the prevalence of megabacteria in budgerigar-breeding colonies and to evaluate possible methods to reduce the prevalence.
Design A monitoring study over several years.
Sample population Two budgerigar ( Melopsittacus undulatus ) colonies with over 300 birds each.
Procedure The prevalence of megabacteria in the faeces in two budgerigar breeding colonies, colony 1 and 2, was determined by faecal examination of each bird. Following an initial survey (1990), most of the birds that were scored 2+ or more were culled and a management practice was implemented to discriminate against positive birds. Consecutive yearly surveys (1991, 1992) were conducted on the young birds bred in these colonies. The prevalence of megabacteria in colony 2 was also evaluated in 1994 and 1996 after all the birds were treated with amphotericin B administered in drinking water.
Results The prevalence of megabacteria in the two colonies was significantly (P < 0.001) different. Overall the prevalence of megabacteria adjusted for colony differences was significantly higher (P < 0.025) in males compared to females. Age was not an influencing factor. After the initial survey, the prevalence in the offspring did not significantly (P > 0.05) decrease in the following two annual breeding seasons but by inference it did significantly decrease after amphotericin B treatment.
Conclusion The practice of culling most birds with more megabacteria in faeces and discriminating against positive birds when selecting birds for breeding or culling birds on show quality does not decrease megabacteria prevalence in the offspring. However, a reduction in prevalence does occur with administration of amphotericin B. Birds may have amphotericin B-resistant organisms and these birds need to be identified and culled.  相似文献   
5.
Objective   Validation of a stimulation test for determining the steroidogenic capacity of the parrot testis. The major aim was to characterise testosterone secretion after injection of a gonadotropin-releasing hormone agonist (GnRHa), then use the test to investigate seasonal reproduction in the male cockatiel.
Procedure   A synthetic GnRHa (buserelin; 8.0 µg of peptide/kg bodyweight) was injected IM into male cockatiels (n = 7) and sulphur-crested cockatoos (n = 3) and serial blood samples collected at 0, 30, 60, 90 and 120 min after administration. Once validated, the technique was subsequently used to examine seasonal changes (23 months) in the testosterone profile of a captive cockatiel population.
Results   Injection of buserelin resulted in a significant increase in the testosterone concentration of cockatiel plasma, with maximal concentrations occurring at approximately 60 (1.33 ± 0.08 ng/mL) to 90 min (1.22 ± 0.08 ng/mL) after injection. Although no clear pattern of seasonal variation in testosterone secretion was detected in cockatiel plasma, samples taken 60 and 90 min after administration showed a significant increase in all seasons. Injection of buserelin in the sulphur-crested cockatoo also resulted in increased testosterone secretion, with maximal concentrations obtained after 90 min.
Conclusion   Buserelin can be used to obtain a reliable index of the prevailing testosterone capacity of the cockatiel and cockatoo testis. With further studies, this test may be incorporated into clinical assessment of reproductive status.  相似文献   
6.
SUMMARY An aqueous suspension of air-dried, hammer-milled leaf of Terminalla oblongata (yellow-wood) was administered to sheep by gavage, as a single dose of 5 to 20 g (dry weight)/kg body weight. Doses of 15 g/kg, or more, caused depression, Inappetence, abdominal pain and reduced ruminal movements within 24 to 48 h and some sheep also showed dyspnoea, oplsthotonus and champing of the Jaws. Haematology and blood gas and acid-base measurements were unaffected. In sheep given a dose of 12.5 g/kg, or more, plasma osmolality, aspartate aminotransferase activity and potassium and bilirubin concentrations Increased while plasma total protein markedly decreased and plasma sodium concentration and alkaline phosphatase activity remained normal. Most sheep were necropsled 48 h after dosing. The liver showed zonal hepatocellular necrosis, the pattern of which varied with the dose given. No renal lesions were observed, although one sheep given a very high dose became azotaemic and hyperkalaemic. Hydrothorax, hydroperlcardlum and ascltes developed In sheep given doses of 15 or 20 g/kg.  相似文献   
7.
Kenaf (Hibiscus cannabinus L.) is an annual plant which produces a very high fiber yield per hectare and has demonstrated to be a suitable material for pulping. The crop conditions influence fiber production, but there is no information about their effect on pulp quality. The aim of this work was to study the effect of kenaf varieties and crop conditions (watering dose and harvesting time) on sulfate pulp quality. The study has been made on bast fiber sulfate pulps due to their high added value. The quality criteria were fiber dimensions, chemical composition and pulp quality. Kenaf variety or crop conditions have significant effect on fiber dimensions, holocellulose content, kappa number and breaking strength. To obtain high fiber yield and good delignified pulps it is recommended to grow the Salvador variety and to employ advance harvesting. Received: 20 January 1999  相似文献   
8.
9.
Objective To survey finches in pet shops for Cochlosoma infection and evaluate the efficacy of antiprotozoal therapy with metronidazole or ronidazole.
Design A survey of pet shop finches and drug efficacy trials.
Procedure Finches in pet shops were randomly selected and their faeces examined microscopically for motile Cochlosoma sp trophozoites. Drug trials were carried out on 60 adult finches with naturally occurring infections. Body weight was measured and the faeces of each bird was examined for trophozoites at the beginning and 7 days after the end of treatment. In some birds, additional daily faecal examinations were done until three consecutive negative results were obtained. Metronidazole was administered at various dose rates by crop gavage or in drinking water to eight groups of five to ten finches each. Ronidazole was given in water for 7 days to ten finches. In addition, six finches whose faeces tested positive were necropsied and their tissues collected for histological examination.
Results Motile flagellates in the faeces were identified as C anatis -like protozoa. Red-headed parrot-finches, Bengalese and Lady Gould finches were found to be most commonly infected. Cochlosoma sp was also found in the blue-faced parrot-finch, zebra finch, painted finch, nutmeg mannikin and double-barred finch. Metronidazole and ronidazole were found to be effective against Cochlosoma sp. Histological findings on infected adult finches were normal, except for the presence of numerous flagellates between the colorectal villi and cloacal mucosal folds.
Conclusions Cochlosoma anatis -like organisms can infect several species of finches and in adult finches are confined to the colorectum and cloaca. Infection in adult finches was mostly subclinical and could be treated effectively with metronidazole or ronidazole.  相似文献   
10.
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