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J J Cowley J H Gutierrez A C Warnick J F Hentges J P Feaster 《Journal of animal science》1971,32(5):981-983
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Calves born in late September to early October in 1956, 1957 and 1958 were reared at pasture. They were fed milk substitute, supplemented in some cases with concentrate feeding-stuffs.
The losses due to outdoor rearing were low, and calves made satisfactory gains in weight. By rearing at pasture, a considerable saving was effected in the weight of concentrates and hay consumed, while no marked response to the feeding of these supplements before weaning was found. Animals born in the autumn of 1957 and reared on this system reached 10 cwt. in less than 24 months. 相似文献
The losses due to outdoor rearing were low, and calves made satisfactory gains in weight. By rearing at pasture, a considerable saving was effected in the weight of concentrates and hay consumed, while no marked response to the feeding of these supplements before weaning was found. Animals born in the autumn of 1957 and reared on this system reached 10 cwt. in less than 24 months. 相似文献
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Alternaria alternata, the causal agent of Alternaria brown spot (ABS), causes necrosis on leaves, twigs, and fruit, reducing the productivity and quality of fruits. Tangerines and their hybrids are highly susceptible to the disease. Species, hybrids, and cultivars of Citrus from the germplasm bank of the Estação Experimental de Citricultura de Bebedouro, São Paulo, Brazil, were evaluated in 2004 and 2005 with respect to their resistance to A. alternata, both through natural infection and by inoculation. Detached leaves were also used to demonstrate susceptibility or resistance to the disease. Ten cultivars of Satsumas (Citrus unshiu), and 14 cultivars of Clementine mandarin (C. clementina) did not show any symptoms of the disease in their leaves, either through natural infection or when inoculated in the field. The Burguess SRA-412, Wallent SRA-438, Carvalhais, Ampefy SRA-459, Ananas SRA, and Macaque SRA-426 mandarin hybrids (C. reticulata) did not show symptoms of the disease under natural or artificial infection in the field. Some cultivars of C. deliciosa, C. tangerina, C. erythrosa, and C. temple showed symptoms of the disease, even though no previous record of their susceptibility to Alternaria brown spot had been previously reported. The hybrids Fairchild, Nova, Page, Fortune, and Sunburst were susceptible to the disease. However, Fremont mandarin (a crossing between C. clementina and C. reticulata), Encore (C. nobilis × C. deliciosa), and Fallglo (C. reticulata × C. paradisi) did not show symptoms in field, and few symptoms were verified in detached leaves. These materials are promising for the cultivation of tangerines, and will enable genetic improvement for the development of cultivars resistant to Alternaria brown spot. 相似文献