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排序方式： 共有1088条查询结果，搜索用时 15 毫秒
1.
Frdrick G. Sunstrum Wubishet A. Bekele Charlene P. Wight Weikai Yan Yuanhong Chen Nicholas A. Tinker 《Plant Breeding》2019,138(1):82-94
We developed 178 recombinant inbred lines from a southern‐by‐spring oat population designated as “TxH.” These lines were genotyped to generate a high‐quality linkage map that resolved 6,902 markers into 21 linkage groups that matched closely with the latest hexaploid oat consensus map. Three major quantitative trait loci (QTLs) affecting heading date were found in locations that are consistent with known QTLs and candidate genes, and two other QTLs affecting heading date were found in novel locations. Five QTLs affecting plant height were found. Both sets of QTLs are responsible for transgressive segregation observed for these two traits. Four QTLs affecting resistance to crown rust, caused by the pathogen Puccinia coronata f. sp. avenae, were identified. Two of these QTLs are consistent with known clusters of rust resistance genes, while two may represent new locations of novel rust resistance genes. A complete set of SNP sequences suitable for generating markers for molecular selection is provided. 相似文献
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Effect of age on absorption and immune responses to weaning or introduction of novel dietary antigens in pigs 总被引：14，自引：0，他引：14
Pigs weaned at three weeks old absorb food protein antigens from the intestine. The amount of antigen absorbed declines over the next three weeks, and this decline is associated with an increasing level of serum antibody to the fed proteins. There was no difference in the rate of immune elimination of intravenously injected antigen in fed and unfed controls. The reduction of serum antigen is thus likely to reflect reduced absorption, possibly mediated by locally produced antibody. Pigs weaned at 10 weeks old also absorbed antigens and produced an antibody response when introduced to soya; and after three weeks of feeding soya the absorption of antigen was substantially reduced. This latter exclusion was specific for soya as a second novel protein (ovalbumin) was absorbed when introduced to the diet at this time. At six months, pigs no longer absorbed soya proteins when they were introduced to the diet. Furthermore, pigs of this age had serum 'antibody' to soya and other proteins such as keyhole limpet haemocyanin to which they had never been exposed. 相似文献
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Newby TJ Stokes CR Huntley J Evans P Bourne FJ 《Veterinary immunology and immunopathology》1979,1(1):37-47
The immune response of pigs fed 200 mg per day of dinitrophenylated bovine gamma globulin has been evaluated in terms of the antibody and lymphocyte responses and of the induction of tolerance and immune exclusion. Although dosing for ten days resulted in a small IgA response as indicated by splenic plaque forming cells, serum antibody could only be detected when dosing was continued for 42 days. secretory antibody was detected at any time. Antigen feeding for two weeks rendered the animals hyporesponsive to subsequent parenteral antigenic challenge but had little effect upon their ability to exclude an oral dose of antigen from the circulation. 相似文献
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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.相似文献
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Comparative,multidimensional imaging of patent ductus arteriosus and a proposed update to the morphology classification system for dogs 
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Krystina D. Mossop Nicholas P. Moran David G. Chapple Bob B. M. Wong 《Landscape Ecology》2017,32(5):1065-1078