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This paper describes the clinical, haematological, immunohistochemical and pathological findings in 10 female cattle with cutaneous lymphoma. The most striking clinical finding was multifocal intracutaneous nodules, which were firm, hairless and sometimes covered with haemorrhagic crusts. All the animals had multiple lymphadenopathy. Eight of the animals had leucocytosis and two also had lymphocytosis. In seven animals, a definitive diagnosis of lymphosarcoma was made on the basis of biopsies of intracutaneous nodules or fine needle aspirates of superficial lymph nodes. In some of the cattle the kidneys, heart, spleen and lungs were affected.  相似文献   
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If real prices for fish remain at the levels they had attained by 1999, in the year 2050 demand for fish and shellfish as food could be of the order of 270 million tons (live weight equivalent) per year. If producers were able to supply these quantities consumption would rise by 176% over this 50-year period. To meet the demand supply would have to expand at the rate of 2.1% annually; but, a review of the pattern of population growth--and of historical patterns of increases in per capita consumption of fish--shows that annual growth in the volume of fish demanded is likely to be largest in the coming two decades, and then to taper off. Will producers be able to deliver? It is clear that wild marine stocks at present harvested by capture fishermen cannot support fisheries that would yield much more than 100 million tons per year and of this amount a significant proportion will continue to be used for fish meal and oil production. The question therefore narrows down to: can aquaculture, or non-traditional marine species, supply the required amounts? The historical context of supply is considerably different from that which has prevailed during the past 30 years. At that time the growing demand in OECD countries was met partly through imports of fish produced in the seas and lakes of developing countries. During coming decades the increased demand in developing countries must be met essentially through their own resources. In fact, in poor countries it seems unlikely that supply will respond to demand unless they experience economic growth.  相似文献   
186.
On the occasion of a large exhibition of pure-breed fancy pigeons 398 animals from 49 different dovecotes were examined for Salmonella shedding. Faecal samples were taken after caging of the birds for the exhibition and after 3 days, before the end of the exhibition. Salmonella were detected in faeces of 28 out of 398 pigeons (7.04%). 10 birds were Salmonella positive only after caging for the exhibition, 10 other animals only before the end of the exhibition, and 8 pigeons at both occasions. The Salmonella positive birds originated from 15 different dovecotes, i.e. in ca. 30% of the dovecotes at the exhibition at least 1 Salmonella positive pigeon was identified. The share of positive birds in these dovecotes varied between 5% and 83%. All Salmonella isolates belonged to the serovar Typhimurium variant copenhagen and were of phage type DT 2. The results of this study do not provide complete evidence on the spreading of Salmonella organisms from birds infected at time of caging to other pigeons during the exhibition, however, such transmission cannot be excluded. In only 18 dovecotes pigeons were immunised against Salmonella Typhimurium. However, in these dovecotes all breeder birds but only 13% of the young pigeons had been immunised. Among the vaccinated breeder pigeons the number of Salmonella positive birds was considerably lower (not significant) than among the non-vaccinated breeders. There is epidemiological evidence that vaccination of pigeons has a considerable protective effect against Salmonella exposure. However, in order to effectively reduce Salmonella findings in pure-breed fancy pigeons it is recommended to provide vaccination to pigeons in a greater number of dovecotes and to include the progeny, too.  相似文献   
187.
Protothecosis is a severe form of mastitis in dairy cows caused by colorless algae of the genus Prototheca. Since P. zopfii is highly resistant to all known chemotherapeutics, infected cows must be removed from the herd. Eradication measures are difficult since many chronically infected cows may become intermittent shedders. Therefore, cultural methods are insufficient for control measures. In order to eradicate Prototheca zopfii-mastitis in dairy cattle herds, two isotype specific indirect ELISA for detection of IgA and IgG1 in whey were used in a dairy herd highly affected with protothecal mastitis. All cows (n = 313) were tested four times in intervals of six months. Milk specimens were examined in parallel by cultivation and serologically using two indirect ELISA systems for specific IgA and IgG1 in whey. Cows tested Prototheca positive were consequently separated from the herd and slaughtered. At the first examination, 15.6% of the animals were found positive by culture, and 23.3% were positive in at least one of the ELISA systems. Within two years, protothecal prevalence and incidence decreased to zero indicating that the eradication strategy used was successful. In summary, serological identification of P. zopfii-infected lactating cows is an useful tool to eradicate protothecal bovine mastitis in infected herds.  相似文献   
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Panosteitis, an idiopathic bone disease of young dogs, was investigated in the light of a new, empirically based hypothesis governing its pathogenesis. Extensive clinical observations suggest a close relationship between the incidence of this disease and the commercialization of various protein-rich, high-calorie dog foods. The theory of an "osseous compartment syndrome" provides a hypothetical pathogenesis, which corroborates this findings. An excessive accumulation of protein causes intraosseous edema due to its osmotic effects. Because bone is a rigid compartment, this leads to an increase in intramedullary pressure and compression of blood vessels. Subsequent osseous ischemia leads to a deficient metabolic state (decreased oxygenation, inadequate influx of nutritive substances, local acidosis, decreased removal of metabolites, disruption of local biochemical processes, etc.), and a vicious circle is created due to the resulting local inflammation. The disease is aggravated by increased metabolism due to excessive physical activity. Within the context of a pilot study, clinical, radiographic, scintigraphic and thermographic examinations and a therapeutic trial with benzopyron were carried out. In addition, more modern investigative tools, including osteomyelography, magnetic resonance tomography and intraosseous pressure measurements were used to provide objective data concerning the pathogenesis of panosteitis. In most cases, clinical remission was seen within days of monotherapy with the proteolytic substance, benzopyron (Cumartrin). This finding appears to corroborate our hypothesis.  相似文献   
190.
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