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排序方式: 共有413条查询结果,搜索用时 31 毫秒
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176.
M.T. Srensen E.M. Vestergaard S.K. Jensen C. Lauridsen S. Hjsgaard 《Livestock Science》2009,123(2-3):314-321
Four dietary factors (ad libitum versus feed restriction, control versus protein restriction at ad libitum feeding, control versus inclusion of lupin as a protein source at ad libitum feeding, and control versus extra vitamin E at ad libitum feeding) were tested in four separate experiments for the effect on diarrhoea. To introduce a diarrhoea-like condition, half of the piglets were challenged with an E. coli O 149 dose of 1 × 108 colony forming units on days one and two after weaning (day of weaning = day zero). All piglets were susceptible since the dams were tested mono-zygotic susceptible to the attachment site of E. coli O 149 in the intestines. Each of the four experiments included 32 piglets from 4 sows. The design was a 2 × 2 factorial with dietary factor and E. coli O 149 challenge as the two factors, each at two levels. The piglets were housed individually during the experiment which lasted for 10 days from weaning at 7 weeks of age. The daily recordings included feed intake, weight and faecal score (from 1 = solid and cloddy to 6 = watery and yellow). Faeces from days 1 to 4 were tested for E. coli strains. In addition, blood was sampled and serum was analysed for antibodies to E. coli, IgG and IgM. Generally the E. coli challenge had no effect on growth and feed intake whereas faecal score and number of faecal haemolytic bacteria increased and faecal dry matter decreased. Feed restriction decreased the weight gain while faecal characteristics were unaffected. An analysis including all four experiments revealed that a feed intake of less than 200 g during the first day after weaning seems to be associated with a relatively high incidence of a post-weaning diarrhoea-like condition. Protein restriction decreased faecal score and increased faecal dry matter while weight gain tended to decrease. Inclusion of lupin affected neither weight gain nor faecal characteristics. Extra vitamin E did not affect weight gain while faecal dry matter decreased, and faecal score and number of faecal haemolytic bacteria increased. The dietary treatments had no effect on the measured immunoglobulins. In conclusion, the studied dietary factors could not alleviate a diarrhoea-like condition and at the same time maintain the growth rate. Furthermore, the results indicate that performance can be improved if piglets achieve a daily feed intake of at least 200 g during the first day after weaning. 相似文献
177.
Baron CP Kjaersgård IV Jessen F Jacobsen C 《Journal of agricultural and food chemistry》2007,55(20):8118-8125
This study aimed at investigating protein and lipid oxidation during frozen storage of rainbow trout. Rainbow trout fillets were stored for 13 months at -20, -30, or -80 degrees C, and samples were analyzed at regular intervals for lipid and protein oxidation markers. Lipid oxidation was followed by measuring lipid hydroperoxides (PV), as well as secondary oxidation products (volatiles) using dynamic headspace GC-MS. Free fatty acids (FFA) were measured as an estimation of lipolysis. Protein oxidation was followed using the spectrophotometric determination of protein carbonyls and immunoblotting. Significant oxidation was observed in samples stored at -20 degrees C, and at this temperature lipid and protein oxidation seemed to develop simultaneously. FFA, PV, and carbonyls increased significantly for the fish stored at -20 degrees C, whereas the fish stored at -30 and -80 degrees C did not show any increase in oxidation during the entire storage period when these methods were used. In contrast, the more sensitive GC-MS method used for measurement of the volatiles showed that the fish stored at -30 degrees C oxidized more quickly than those stored at -80 degrees C. Detection of protein oxidation using immunoblotting revealed that high molecular weight proteins were oxidized already at t = 0 and that no new protein oxidized during storage irrespective of the storage time and temperature. The results emphasize the need for the development of more sensitive and reliable methods to study protein oxidation in order to gain more explicit knowledge about the significance of protein oxidation for food quality and, especially, to correlate protein oxidation with physical and functional properties of foods. 相似文献
178.
Hill Z Kirkwood B Kendall C Adjei E Arthur P Agyemang CT 《Public health nutrition》2007,10(8):827-833
OBJECTIVE: To identify regimen, individual, community and cultural factors that affect adoption and adherence to weekly vitamin A supplementation in Ghana. DESIGN: Fifty semi-structured interviews were conducted with women who would be eligible for vitamin A supplementation, 30 with husbands, and 13 with drug sellers, birth attendants and health workers. Six focus group discussions were also conducted with women. These interviews were followed by a 4-month capsule trial with 60 women. Data from a previously conducted communication channel survey of 332 women were also reviewed. SETTING: The study was conducted in Kintampo District in central Ghana. SUBJECTS: Participants for the semi-structured interviews and focus groups were selected from four villages and the district capital, and women in the capsule trial were selected at random from two villages. RESULTS: Knowledge of vitamins was low and taking 'medicines' for long periods and when healthy is a new concept. In spite of this, long-term supplementation will be accepted if motives are explained, specific questions answered and clear instructions are given. Potential barriers included the idea of 'doctor' medicines as curative, false expectations of the supplement, forgetting to take the supplement, losing the supplement, travelling, lack of motivation, perceived side-effects, concerns that the supplement is really family planning or will make delivery difficult, and concerns about taking the supplement with other 'doctor' or herbal medicine, or when pregnant or breast-feeding, or if childless. CONCLUSION: Successful supplementation programmes require appropriately designed information, education and communication strategies. Designing such strategies requires pre-programme formative research to uncover barriers and facilitators for supplementation. 相似文献
179.
A case series of nine domestic cats with culture-confirmed Alternaria species infection is presented, with conclusions drawn regarding signalment, clinical signs, treatment and outcome. Middle aged neutered males were over-represented and all presented with cutaneous lesions involving the extremities (nose, pinnae and digits). Lesions were mainly slow-growing, poorly circumscribed nodules or plaques but some also presented as non-healing wounds. A combination of surgical excision with adjunctive medical therapy appeared to be the most successful treatment option but long courses of medical therapy were generally required and recurrence was common. 相似文献
180.
Summary For the past 10 years, the Andean-type Phaseolus vulgaris cultivar Kranskop has played an important role in South African bean production and breeding. Kranskop shares an ancestor with the internationally important Andean-type rust differential cultivar Redlands Pioneer. The Ur-13 gene in Kranskop and Redlands Pioneer gives protection to numerous internationally reported races of Uromyces appendiculatus and it is imperative to retain this gene in local breeding programmes.In this study, three co-dominant SCAR markers (SEAACMACC430/405, SEACAMCTT310/288 and SEAAGMCGT436
Hha I186/250) were used to trace the origin of Ur-13, and its presence in 71 germplasm accessions, including the international rust differential lines and additional sources of already characterized genes, as well as 78 breeding lines.Each marker was present in approximately 30% of the accessions tested. Only accessions belonging to the Kranskop or Redlands groups contained all three markers. Contrary to expectations, the first two markers, as well as Ur-13, appeared to have originated from a Middle-American-type parent of the Redlands group, California Small White 643, whereas the third marker probably came from the Andean-type cultivar Brown Beauty. This has important implications for the new set of differential lines, as Redlands Pioneer can no longer be regarded as a representative of the Andean gene pool. The markers, in particular SEAACMACC430/405, will be useful in tracing Ur-13 in large seeded breeding material, except where lines such as Mexico 309, PI 181996 and A 286 are used as donors of additional rust resistance genes, as these have the positive alleles of both SEAACMACC430/405 and SEACAMCTT310/288.Part of a Ph.D thesis submitted by the first author to the Department of Plant Sciences, University of the Free State. 相似文献