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331.
Intact chicks and those that had their glands of Harder (GH) removed (GHx) at 1 day of age were studied for their response to optically or intraperitoneally (IP) applied antigens. Following exposure of the chicks to sheep red blood cells (SRBCs), killed Brucella abortus, or bovine serum albumin (BSA), serum and tear samples were collected and assayed for antibodies. Of the two sources of antibodies, the serum generally had higher levels than did the tears. The only exception to this occurred in the intact chicks inoculated by the eye, in which serum and tear levels were equivalent. With SRBCs, no difference could be detected between the two routes of inoculation. However, IP inoculation produced higher levels of antibody in the serum of intact and GHx chicks inoculated with B. abortus or BSA and in the tears of the GHx chicks exposed to B. abortus. Removal of the GH resulted in a consistent decrease in antibody levels in the tears, regardless of the route of exposure. Although this effect was noted with all three antigens, it was more pronounced in the trials using B. abortus and BSA. This finding is discussed in terms of describing the importance of the GH as a source of antibodies to optically applied antigens, and its importance as a route of circulating antibody egress. Furthermore, the feasibility of using the antibody response in tears to a test antigen is discussed as a means of measuring the immune status of a functioning GH. 相似文献
332.
Oesophagogastric parakeratosis in the growing pig: effects of the physical form of barley-based diets and added fibre 总被引:1,自引:0,他引:1
In four experiments a total of 288 individually fed pigs were given barley-based diets for about 100 days from about 20 kg liveweight. Fine grinding of barley increased the number and severity of oesophagogastric lesions. Pelleting a diet based on coarsely ground barley had a similar effect. Coarser grinding of the barley and substituting small proportions of oat husk, but not of bran, gave lower incidences and severities of lesions. The performance responses of the pigs differed and give a framework for deciding on the balance to be struck between optimal performance and the risk of lesion development. 相似文献
333.
A review of investigations of the functional anatomy of the equine foot is presented. Emphasis is placed on the relationships of structures involved in the major diseases of the foot. 相似文献
334.
In this paper, a case of otitis media with effusion (‘glue ear’) is described in a Cavalier King Charles spaniel. Its presentation, diagnosis and surgical management by the insertion of a trans-tympanic ventilation tube (grommet) is discussed. 相似文献
335.
336.
Douglas Tave Mahmoud Rezk R. Oneal Smitherman 《Journal of the World Aquaculture Society》1989,20(4):214-222
Gold, bronze, and black (normal pigmentation) body colors in Tilapia mossambica are controlled by a single autosomal gene with incomplete dominant gene action: GG fish are black gg fish are gold; Gg fish are bronze. Because gold body color is produced by the recessive genotype, it is easy to produce and to maintain a truebreeding population of gold T. mossambica for commercial purposes. If all other colors are culled, the population will breed true, because gold × gold will always produce 100% gold offspring. The G gene will be a valuable genetic marker for many genetic studies, such as the production of gynogenetic T. mossambica . 相似文献
337.
I. HATALA-ZSELLR 《EPPO Bulletin》1992,22(3):411-415
The area of protected crops in Hungary is about 5300 ha. Most of it is under plastic, the area under glass being only about 250 ha. Vegetable growing makes up 80%, mostly on private farms. The main crops are capsicum, tomato and cucumber. On relatively small areas, ornamentals, principally cut flowers, are produced: carnation, gerbera, rose and chrysanthemum. The three most important, commonly occurring pests are Trialeurodes vaporariorum, Tetranychus urticae and aphids (Aphis gossypii, Myzus persicae, A. nasturtii). Polyphagotarsonemus latus, Liriomyza trifolii and Aculops lycopersici caused considerable economic damage during the eighties. However, in the last few years these pests have not been observed in any crops. Two new glasshouse pests have been described from ornamentals during the last 2 years in Hungary: Frankliniella occidentalis and Bemisia tabaci. Their accidental appearance in vegetable crops could lead to direct economic loss, besides endangering biological control systems. 相似文献
338.
In this study, the effects of nitrogen (N) rate (60, 120, 180 and 240 kg N ha?1 applied in three equal dressings at seeding and after the first and second cuttings) and stubble height (7, 14 and 21 cm) on the dry matter (DM) yield, crude protein (CP) content, and CP yield of a sorghum–sudangrass hybrid [Sorghum bicolor (L.) Moench × Sorghum sudanense (Piper) Stapf., cv. Pioneer 988] in the three‐cut system was investigated. The N rate had no significant effect in the first and third cuttings, but in the second cutting DM yields increased significantly with increase in N rate. The highest yield of 9.1 t ha?1 was obtained with 80 kg N ha?1 for the average of 2 years at the second cutting, but no significant difference was found among the 40, 60 and 80 kg N ha?1 rates. CP content and yield were not significantly affected by N rate at the first and third cuttings, but CP content and yield were significantly affected by application of N at the second cutting. Stubble height had a significant effect on CP content at the third cutting. However, it had no significant effect on CP content at the first and second cuttings. Stubble height had a significant effect on the CP yield at the first cutting, but no significant effect on CP yield at the second and third cuttings. 相似文献
339.
340.
Eastman CR 《Science (New York, N.Y.)》1906,24(625):822-823