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991.
The clinical symptoms and pathology in 33 adult sheep and 31 adult goats experimentally infected with Wesselsbron disease virus are described. There was moderate to severe hyperthermia in most animals, but no other clinical signs of disease or deaths were recorded. Eleven sheep and 6 goats were sacrificed for pathological studies at various stages during the febrile response. The macroscopic and microscopic lesions in these cases are described. Microscopic studies revealed that the liver was consistently affected and showed small foci of necrosis. These were sparsely distributed and associated with a marked localized Kupffer cell response ("retothelial nodules"). In addition, acidophilic bodies and small groups of necrotic hepatocytes were evident in some lobules. Apart from the hepatic lesions, mild to moderate pyknosis and karyorrhexis of lymphocytes were seen in the spleen and lymph nodes. This report also compares the microscopic lesions in the livers of adult sheep and goats with those of new-born lambs for Wesselsbron disease as well as with those reported for Rift Valley fever in adult sheep.  相似文献   
992.
An 18-month old Friesian heifer which had lost condition and had diarrhoea for several weeks was diagnosed by haematological and pathological examinations as having lymphocytic leukaemia. True lymphatic leukaemia has not previously been described in cattle and does not readily fit into presently accepted classifications of bovine leukosis.  相似文献   
993.
A histopathological survey of 945 abattoir-derived adult bovine terminal ilea was conducted. All samples showed changes interpreted as chronic enteritis. Sixty-nine percent had glandular epithelium within submucosal Peyer's patches. Thirty-eight percent showed dense focal lymphoid aggregations within the mucosa and twenty-seven percent showed sub-mucosal abscessation and granulomata. Evidence of coccidial and nematode parasitism was common. Four percent had Johne;s disease.  相似文献   
994.
Two Collie working dogs were examined because of the sudden appearance of a skin condition. Both dogs were depressed and anorectic with an acute exudative dermatitis confined to areas of non-pigmented skin. Antibacterial treatment was instituted initially followed by long-term use of a sun-protective cream. A diagnosis of photosensitive dermatitis was made but the cause of the photosensitivity was not determined.  相似文献   
995.
996.
Summary Tick populations were observed on zebu(Bos indicus) cattle over a period of 2 years at Entebbe, Uganda where the climate was thought to be highly favourable for the free-living stages of ticks. Collections of all instars of ticks were made from the body surfaces of the cattle at intervals of between 1 and 5 weeks. The species recorded in order of decreasing abundance wereRhipicephalus appendiculatus, Amblyomma variegatum, Boophilus decoloratus, Rhipicephalus evertsi evertsi, Rhipicephalus simus, Rhipicephalus compositus andHyalomma marginatum rufipes. The rankings of the cattle based on burdens of any particular species of tick were always correlated with their rankings for other species; animals that carried more adult stages of a species also carried more of its immature stages. There were more adult males than females ofR. appendiculatus, A. variegatum andR. e. evertsi even when the cattle had had all ticks removed 1 week previously; several possible mechanisms are suggested to explain the biased sex ratio. It is concluded that there is promise for improvement in control of 3-host ticks by increasing the resistance of herds of zebu cattle by culling or selective breeding.
Relacion Entre Garrapatas Y Ganado Cebu En El Sur De Uganda
Resumen Se observaron las poblaciones de garrapatas en ganado cebú (Bos indicus) en Entebe, Uganda, donde el clima parecía favorecer a los estados libres de las garrapatas. Las observaciones duraron dos años. Las colecciones de los estadios larvales se realizaron con intervalos de 1 a 5 semanas. Las especies identificadas en orden numérico decreciente fueronRhipicephalus appendiculatus, Amblyommavariegatum, Boophilus decoloratus, Rhipicephalus evertsi evertsi, Rhipicephalus simus, Rhipicephalus compositu andHyalomma marginatum rufipes. Los rangos del ganado basados en la carga de garrapatas de una especie en particular, tuvieron correlación en rangos para otras especies en los animales que tuvieron una carga mayor de etapas maduras de una especie se observaron tambie más ejemplos de las etapas no maduras. Hubo más machos adultos que (hembras deR. appendiculatus, A. variegatum yR. e. evertsi aun cuando todas las garrapatas del ganado habían sido removidas 1 semana previamente; se sugieren varios mecanismos para explicar este fenómeno. Se concluye que existe una posibilidad para controlar garrapatas de 3 huéspedes, incrementando la resistencia de ganado cebú mediante selección y cruzamiento de animales resistentes.

Relation Entre Les Tiques Et Les Zebus Dans Le Sud-Est De L'Ouganda
Résumé Des populations de tiques ont été observées sur des zébus (Bos indicus) pendant 2 ans à Entebbe, en Ouganda où le climat est connu pour être très favorable aux stades libres des tiques. Des collections de tous les stades de tiques présentes sur le corps des animaux ont été faites à des intervalles allant de 1 à 5 semaines. Les espèces suivantes ont été recueillies dans l'ordre d'abondance décroissante:Rhipicephalus appendiculatus, Amblyomma variegatum, Boophilus decoloratus, Rhipicephalus evertsi evertsi, Rhipicephalus simus, Rhipicephalus compositus etHyalomma marginatum rufipes. Le classement du bétail basé sur la charge en une espèce de tique a toujours été en corrélation avec la charge dans les autres espèces de tiques. Les animaux porteurs du plus grand nombre d'adultes d'une espèce étaient également porteurs du plus grand nombre de stades préimaginaux. Il y avait beaucoup plus de mâles que de femelles deR. appendiculatus, A. variegatum etR. e. evertsi même lorsqu'on avait prélevé toutes les tiques sur le bétail une semaine auparavant. Plusieurs mécanismes possibles sont suggérés pour expliquer le déséquilibre dans le pourcentage des sexes. La conclusion porte sur les promesses d'amélioration de la lutte contre les tiques trixènes par l'accroissement de la résistance des troupeaux de zébus par élevage sélectif.
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997.
998.
In recent years in the Netherlands a second mushroom species,Agaricus bitorquis, which prefers higher temperatures thanA. bisporus and is less susceptible to certain diseases, is often commercially grown.Verticillium fungicola var.fungicola, the causal agent of dry bubble, is responsible for considerable damage in crops ofA. bisporus. InA. bitorquis, however, dry bubble has hardly been noticed, but brown spots due toV. fungicola var.aleophilum resulted in inferior mushroom quality. The latter variety also caused brown spots ina. bisporus, but to a minor degree. In variety Les Miz 60 ofA. bisporus, however, it also induced fruit-body deformation in a way different from dry bubble. Verticillium psalliotae, isolated fromA. bitorquis in England, induced more confluent brown spots inA. bitorquis. In the netherlands, where moreA. bitorquis is grown than in other countries,V. psalliotae has not yet been encountered in crops ofA. bitorquis. V. psalliotae, which has a high temperature optimum for mycelial growth, likeV. fungicola var.aleophilum andA. bitorquis, did not infectA. bisporus in our trials.Artificial infection ofA. bisporus orA. bitorquis could not be accomplished with the following related and/or fungicolous fungi:Verticillium lamellicola, V. fungicola var.flavidum, V. biguttatum, Nectriopsis tubariicola, Acremonium crotocinigenum andAphanocladium album.Samenvatting Vooral in Nederland wordt sinds een aantal jaren naastAgaricus bisporus ook de warmteminnende champignonsoortAgaricus bitorquis geteeld, die minder vatbaar is voor bepaalde ziekten. TerwijlVerticillium fungicola varfungicola in de teelt vanA. bisporus droge mollen en daardoor veel schade veroorzaakt, komen in de teelt vanA. bitorquis geen droge mollen voor maar wel bruine vlekken, die tot kwaliteitsverlies en dus schade leiden. De vlekken bleken veroorzaakt te worden doorV. fungicola var.aleophilum. Deze schimmel veroorzaakte ook inA. bisporus bruine vlekken, hoewel in minder ernstige mate, maar in het ras Les Miz 60 vanA. bisporus bovendien misvormde champignons, die wel op droge mollen leken, maar daaraan niet gelijk waren.OokV. psalliotae, in Engeland geïsoleerd vanA. bitorquis met vlekken, veroorzaakte wat meer samenvloeiende, bruine vlekken inA. bitorquis. In Nederland, waar meerA. bitorquis geteeld wordt dan in andere landen, isV. psalliotae nog niet aangetroffen in teelten vanA. bitorquis. InA. bisporus kon geen kunstmatige infectie worden verkregen metV. psalliotae, die net alsV. fungicola var.aleophilum enA. bitorquis warmteminnend genoemd zou kunnen worden.Met de volgendeVerticillium-achtige of van paddestoelen geïsoleerde schimmels kon evenmin op kunstmatige wijze een infectie worden opgeroepen inA. bisporus ofA. bitorquis: Verticillium lamellicola, V. fungicola var.flavidum, V. biguttatum, Nectriopsis tubariicola, Acremonium crotocinigenum enAphanocladium album.  相似文献   
999.
Fenarimol-resistant isolates ofPenicillium italicum with cross-resistance to imidazole and triazole fungicides which inhibit ergosterol biosynthesis were tested for their sensitivity to fenpropimorph. Radial growth tests on PDA showed that the isolates (n=6) lacked cross-resistance to fenpropimorph or displayed enhanced sensitivity to the fungicide (negatively correlated cross-resistance). Control of blue mold decay of oranges incited by the wild-type isolate could be achieved by dipping fruits in suspensions of fenpropimorph at a concentration of 100 mg ml–1. Decay of oranges incited by the fenarimol-resistant isolates was controlled at the same or at a lower concentration (30 mg ml–1), thus showing that the normal or increased sensitivity to fenpropimorph is also expressed under in vivo conditions.Samenvatting Fenarimol-resistente isolaten vanPenicillium italicum met kruisresistentie tegen imidazool-en triazoolfungiciden die de ergosterolbiosynthese remmen, werden getoetst op hun gevoeligheid voor fenpropimorf. Radiale groeiproeven op PDA toonden aan dat de isolaten (n=6) geen kruisresistentie bezaten met fenpropimorf of een verhoogde gevoeligheid voor het middel vertoonden (negatief gecorreleerde kruisresistentie). Op sinaasappels konPenicillium-rot, veroorzaakt door het wild-type bestreden worden door middel van een dompelbehandeling met fenpropimorf bij een dosering van 100 g ml–1). Bestrijding van rot veroorzaakt door fenarimil-resistente isolaten werd verkregen bij dezelfde of een lagere dosering (30 g ml–1); aldus werd aangetoond dat de normale of verhoogde gevoeligheid voor fenpropimorf ook in vivo tot uiting komt.  相似文献   
1000.
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