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71.
D. R. Wise 《British poultry science》1970,11(3):333-339
Skeletal systems of growing broiler and laying strain chickens were compared in an attempt to establish whether the rapid growth rates of broilers lead to qualitative or quantitative skeletal deficiencies. Qualitative comparisons included studies of bone histology and of bone ash, density and compression strength. Quantitative comparisons related bone weight to body weight. Bone “ matured “ very rapidly, as judged by its density, ash content and weight relative to bird weight in the first fortnight of life and thereafter more slowly in both broilers and laying strain birds. After the age of I week bones “ matured “ mainly by replacement of water by mineralised osteoid—the degree of mineralisation of osteoid being a less important factor in bone “ maturation “. There were no significant differences from the viewpoint of either quality or quantity between the skeletal systems of broilers and laying strain birds of the same age. At equal body weights, however, broilers had skeletal systems which were both qualitatively and quantitatively less “ mature “ than those of laying strain birds. These differences were most marked during early life when the rate of skeletal “ maturation “ was high. 相似文献
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From 1999 to 2003, the percentage of actively employed females in the AVMA increased 25.4%, whereas the percentage of males decreased by 0.4%. The number of females increased in all 9 census regions. 相似文献
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Griffin MJ Pote LM Wise DJ Greenway TE Mauel MJ Camus AC 《Journal of aquatic animal health》2008,20(3):127-135
Channel catfish Ictalurus punctatus from a commercial farming operation in the Mississippi Delta were submitted for examination for the presence of infection by the trematode Bolbophorus damnificus. The fish were instead found to possess skin nodules suggestive of Henneguya pellis, a species previously described in the blue catfish I. furcatus. Despite the dermal location and distribution of lesions, morphological characteristics of the myxospores were inconsistent with H. pellis. Spores possessed a lanceolate spore body 15.4 +/- 1.5 microm (mean +/- SD; range = 12.2-19.3 microm) in length and 5.5 +/- 0.6 microm (range = 4.5-6.8 microm) in width in valvular view, and 4.7 +/- 0.2 microm (range = 4.2-5.0 microm) in width in sutural view. Polar capsules were pyriform and unequal in both length and width and contained polar filaments with six coils. Polar capsules measured 6.1 +/- 0.8 microm (range = 4.0-7.9 microm) long and 1.7 +/- 0.3 microm (range = 1.0-2.2 microm) wide. The caudal appendages were 50.5 +/- 8.3 microm (range = 34.8-71.4 micorm) long and the total length of the spore was 65.9 +/- 8.6 microm (range = 48.2-90.0 microm). The "blister like" plasmodia were round or ovoid, up to 2 mm in diameter, and randomly distributed throughout the epidermis of the fish. Histologically, plasmodia were confined to the dermis and elicited no inflammatory reaction from the fish. A blast search of the 18S small subunit rDNA sequence obtained by polymerase chain reaction amplification resulted in no identical sequence matches but indicated a close relationship to H. gurlei, H. ictaluri, and H. exilis. The unique host record, spore morphology, and novel genetic sequence derived from this isolate lead us to propose this isolate as a novel species, H. sutherlandi. 相似文献
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Oats are a good source of many vitamins and minerals, including compounds that collectively constitute vitamin E, the tocols. Tocols are comprised of two subgroups, tocopherols and tocotrienols. Due to their potent antioxidant properties, attention has been given to the health benefits of tocols in oats. However, little is known about developmental aspects of their accumulation. Moreover, aside from their role in protecting membranes from oxidative damage, their possible physiological roles in planta have largely gone uninvestigated. In this study, we quantified tocol accumulation at five time points during oat seed development, and also compared tocol concentration and composition in the whole seed both to endosperm and embryos at a late stage of seed development. The temporal pattern of accumulation of the tocol subgroups was different. Both tocotrienols and tocopherols steadily increased over the course of seed development; however, tocotrienol progression was sigmoidal and tocopherol linear. By the end of seed development, tocotrienols were the most abundant tocol both in whole seed and in seed with embryos removed. In contrast, embryos contained higher concentrations of tocopherols than tocotrienols late in seed development. Differences in both temporal and spatial distribution during seed development suggest distinct roles for tocotrienols and tocopherols. 相似文献
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