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1.
Cumulus-oocyte complexes from hormone-stimulated 3-4-week-old (n=43) and 6-7-week-old (n=12) prepubertal lambs were matured in vitro and incubated with unsorted, or X- or Y-spermatozoa separated with a high-speed cell sorter (SX MoFlo)frozen-thawed. Presumptive zygotes were then cultured to the blastocyst stage, and transferred to recipients fresh or after cryopreservation (frozen). Oocyte cleavage was higher (p <0.05) with unsorted (515/926, 55.6%) than X- or Y-spermatozoa (261/672, 38.8% and 229/651, 35.2%, respectively) and blastocyst formation (% zygotes) by Day 9 of in vitro culture was lower (p <0.05) for X- (102/261, 39.1%) than unsorted spermatozoa (249/515, 48.3%), but did not differ between Y-spermatozoa (103/229, 45.0%) and unsorted spermatozoa, or between X- and Y-spermatozoa (p >0.05). For fresh embryos, survival to term was 50.0% (3/6) for unsorted, 0.0% (0/6) for X- and 16.7% (1/6) for Y-spermatozoa-derived embryos (p >0.05), and for frozen embryos was 4.0% (2/50) for unsorted, 9.1% (2/22) for X- and 2.9% (1/34) Y-spermatozoa-derived embryos (p >0.05). Of the two lambs born from X-spermatozoa-derived embryos, one was female (50%), and from the two Y-spermatozoa-derived lambs, both were male (100%), demonstrating that lambs can be produced after the transfer of fresh and cryopreserved IVP embryos derived from prepubertal lamb oocytes and frozen-thawed sex-sorted sperm.  相似文献   
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We have previously shown that resistance to Leishmania infantum in dogs is associated with a Th1 type of immune response. In this study, we use a canine macrophage cell line (030-D) that can readily be infected with this protozoan parasite. Our aim is to further characterize the effector mechanisms involved in killing of Leishmania parasite in dogs. We observed that activation of 030-D cells by incubation with a supernatant derived from a Leishmania-specific T cell line containing IFN-gamma, TNF-alpha and interleukin-2 (IL-2) resulted in enhanced nitric oxide (NO) production by these cells. In addition, we observed enhanced anti-leishmanial activity of infected 030-cells after activation. Both, NO production and anti-leishmanial activity were abrogated by addition of L-N(G)-nitroargininemethyl ester (L-NAME), an analogue of L-arginine. Thus, NO play an important role in the anti-leishmanial activity of these canine macrophages. We propose the infection of the 030-D cell line as a good in vitro model to further investigate parasite-host cell interactions in dogs, a natural host of Leishmania parasites.  相似文献   
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Side-chain ferroelectric liquid crystalline polymers are currently used in a number of applications, including displays and electrical sensors. Comparisons with existing technologies and materials indicate that relative to ceramics, such polymers have lower figures of merit but offer greater durability in sensor applications.  相似文献   
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An immunofluorescent (IF) test for the serodiagnosis of Toxocara canis infections in puppies is described. Frozen sections of male adult T. canis worms were used as antigen.A group of seven puppies, 6 weeks of age, was infected orally with 10 000 embryonated T. canis eggs each. In the sera of all animals IF antibodies could be detected from approximately 4 weeks after infection onwards. Titers were detectable until the end of the observation period (22 weeks).Two puppies of the same age were infected with 30 000 or 50 000 embryonated T. canis eggs respectively. Positive IF results were also obtained in the sera of these pups from week 4 post infection (p.i.) onwards. No correlation between titer and initial number of egges administered was observed. Furthermore, no correlation was noticed between titer and number of adult worms recovered from the dogs. For comparison all sera were tested with the complement fixation (CF) test, using cuticle material of adult worms as antigen. Complement fixing antibodies could be detected in none of the serum samples.  相似文献   
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Four methods employed in the diagnosis of experimental porcine trichinellosis (trichinoscopy, digestion method, immunofluorescence and enzyme linked immunosorbent assay (ELISA)) were compared by eleven laboratories in the countries of the European Economic Community and Sweden. The aim of this study was to test the reliability of ELISA during the onset of T. spiralis infection. Material from conventionally raised pigs infected with 1500 or 10000 larvae was compared to uninfected controls at Day 17 and Day 21 post infection.The serological techniques gave higher percentages of positive results than the direct techniques. Specific antobodies could be demonstrated with ELISA at an earlier stage and at higher percentages than with the other methods. ELISA micro-assay was the most sensitive procedure.  相似文献   
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Immunoglobulins were analysed in the sera of pigs inoculated once with different numbers of Trichenella spiralis. Analyses for IgE were performed by homologous passive cutaneous anaphylactic (PCA) reactions and for IgG (H + L) by enzyme linked immunosorbent assay (ELISA).In the higher inoculation dose range (5,000–10,000 larvae) IgE production paralleled that of IgG (H + L). In the lower range (150,500 and 1,500 larvae) IgE production preceded IgG production in most animals.The possible significance of this finding for the early diagnosis of T. spiralis infections is discussed.  相似文献   
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Distilleries produce a huge quantity of effluents, popularly known as spent wash (SW), which when bio-methanated produce post-methanation effluents (PME). A field experiment on soybean–wheat system was conducted for five consecutive years in a Vertisol of central India to evaluate the effect of distillery effluent (DE) on soil carbon and nitrogen dynamics. Ten treatment combinations consisting of control, 100% NPK + Farmyard Manure (FYM), and graded level of SW and PME were applied. Total carbon content of soil increased significantly with applications of FYM and DE. SW was found superior in enhancing carbon content of soil in comparison to PME. Farmyard Manure contributed more carbon toward the recalcitrant pool, whereas DE contributed more carbon toward the active and slow pool. Nitrogen (N) availability was significantly improved with the application of DE. Balanced application of DE may act as amendment for increasing C and N stocks in Vertisol.  相似文献   
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