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ChristopheCazaban 《中国牧业通讯》2005,(8):66-67
饮水免疫接种成功与否取决于管理条件,例如水质量、氯离子中和作用、疫苗溶液的分配和利用以及疫苗溶液的摄入率。 相似文献
3.
Casey L. Donnelly MS Christophe Staub PhD Dickson Varner PhD DVM Terry Blanchard PhD DVM Larry Johnson PhD David W. Forrest PhD 《Journal of Equine Veterinary Science》2007,27(5):212-216
Apoptosis is necessary for both initiation and control of spermatogenesis; however, an increase in apoptosis can lead to subfertility/infertility in stallions, causing substantial financial loss in the equine industry. The ability of stem cell factor (SCF), leukemia-inhibiting factor (LIF), granulocyte–macrophage colony-stimulating factor (GM-CSF), and estradiol (E2), alone or in combination, to prevent apoptosis of germ cells in short-term equine testicular cultures was examined. Testicular tissue was sectioned into approximately 2-mm cubes and placed in media-filled culture chambers. Concentrations of SCF (100 ng/mL), LIF (10 ng/mL), GM-CSF (5 ng/mL), and E2 (10−9 mol/l) were added alone or in combination to each well. After 6 hours in culture, the tissue was fixed and immunohistochemically (terminal deoxynucleotidyl transferase-mediated nick-end labeling; TUNEL) stained for apoptosis detection. Apoptotic cells per 100 Sertoli cell nuclei within seminiferous tubules were counted until the 500th Sertoli cell nuclei was reached. This counting procedure was used for each slide. An analysis of variance (ANOVA) with a Tukey's test was used to compare apoptotic rates. In comparison with the control, GM-CSF alone lowered apoptosis by 34.77%. GM-CSF–treated tissue combined with SCF and LIF as well as GM-CSF combined with SCF, LIF, and E2 reduced apoptosis when compared with the control (37.45% and 44.40%, respectively) or other treatment combinations. GM-CSF alone reduced apoptosis; results suggest possible synergy for the combinations of SCF and LIF with GM-CSF and for E2 with SCF, LIF, and GM-CSF. 相似文献
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Marine Remize Frdric Planchon Matthieu Garnier Ai Ning Loh Fabienne Le Grand Antoine Bideau Christophe Lambert Rudolph Corvaisier Aswani Volety Philippe Soudant 《Marine drugs》2022,20(1)
The production of polyunsaturated fatty acids (PUFA) in Tisochrysis lutea was studied using the gradual incorporation of a 13C-enriched isotopic marker, 13CO2, for 24 h during the exponential growth of the algae. The 13C enrichment of eleven fatty acids was followed to understand the synthetic pathways the most likely to form the essential polyunsaturated fatty acids 20:5n-3 (EPA) and 22:6n-3 (DHA) in T. lutea. The fatty acids 16:0, 18:1n-9 + 18:3n-3, 18:2n-6, and 22:5n-6 were the most enriched in 13C. On the contrary, 18:4n-3 and 18:5n-3 were the least enriched in 13C after long chain polyunsaturated fatty acids such as 20:5n-3 or 22:5n-3. The algae appeared to use different routes in parallel to form its polyunsaturated fatty acids. The use of the PKS pathway was hypothesized for polyunsaturated fatty acids with n-6 configuration (such as 22:5n-6) but might also exist for n-3 PUFA (especially 20:5n-3). With regard to the conventional n-3 PUFA pathway, Δ6 desaturation of 18:3n-3 appeared to be the most limiting step for T. lutea, “stopping” at the synthesis of 18:4n-3 and 18:5n-3. These two fatty acids were hypothesized to not undergo any further reaction of elongation and desaturation after being formed and were therefore considered “end-products”. To circumvent this limiting synthetic route, Tisochrysis lutea seemed to have developed an alternative route via Δ8 desaturation to produce longer chain fatty acids such as 20:5n-3 and 22:5n-3. 22:6n-3 presented a lower enrichment and appeared to be produced by a combination of different pathways: the conventional n-3 PUFA pathway by desaturation of 22:5n-3, the alternative route of ω-3 desaturase using 22:5n-6 as precursor, and possibly the PKS pathway. In this study, PKS synthesis looked particularly effective for producing long chain polyunsaturated fatty acids. The rate of enrichment of these compounds hypothetically synthesized by PKS is remarkably fast, making undetectable the 13C incorporation into their precursors. Finally, we identified a protein cluster gathering PKS sequences of proteins that are hypothesized allowing n-3 PUFA synthesis. 相似文献
6.
Impact of xylanases with different substrate selectivity on gluten-starch separation of wheat flour 总被引:1,自引:0,他引:1
The influence on wheat flour gluten-starch separation of a xylanase from Aspergillus aculeatus (XAA) with hydrolysis selectivity toward water extractable arabinoxylan (WE-AX) and that is not inhibited by wheat flour xylanase inhibitors was compared to that of a xylanase from Bacillus subtilis (XBS) with hydrolysis selectivity toward water unextractable arabinoxylan (WU-AX) and that is inhibited by such inhibitors. XAA improved gluten agglomeration through degradation of WE-AX and concomitant reduction in viscosity, which in the laboratory scale batter procedure with a set of vibrating sieves (400, 250, and 125 microm), increased protein recoveries on the 400 microm sieve. In contrast, XBS had a negative effect as it decreased gluten protein recovery on this sieve, probably as a result of the viscosity increase that accompanied WU-AX solubilization. Hence, it was active even if most likely a considerable part of its activity was prevented by xylanase inhibitors. A combination of XAA and XBS at a low dosage yielded a distribution of gluten proteins on the different sieves comparable to that of the control. At a high combined dosage, the gluten agglomeration was better than that with XAA alone, indicating that both WE-AX and WU-AX have a negative impact on gluten agglomeration. Finally, experiments with endoxylanase addition at different moments during the separation process suggest that the status of the arabinoxylan population during dough mixing is far less critical for its impact on gluten agglomeration than that during the batter phase. 相似文献
7.
Christophe Roy Nicolas Vidal-Naquet 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(5):541
Honey bees are most often kept for production purposes. Sanitary, regulatory, or zootechnical circumstances may lead the beekeeper or the veterinarian to dispose of a honey-bee colony. Unfortunately and at present, no standard method of euthanasia exists, leaving the door open to many more or less acceptable practices. Based on a short survey of current practices in 8 countries, we list and rank these methods. Although imperfect, the sulfur dioxide technique appears to be the most efficient. We suggest that it should become the reference method to be taught and incorporated into veterinary and regulatory guidelines. 相似文献
8.
Pierre Feutry Philippe Keith Christophe Pécheyran Fanny Claverie Tony Robinet 《Ecology of Freshwater Fish》2011,20(4):636-645
Abstract – Strontium/Calcium (Sr/Ca) and Barium/Calcium (Ba/Ca) ratios were measured in 60 otoliths of the French Polynesian flagtail Kuhlia malo. Both elemental ratios were needed to correctly distinguish residence in marine, brackish and fresh water. High Sr/Ca and low Ba/Ca around the nucleus of all otoliths provided evidence of marine residency during the early life of all individuals. At about 0.5 mm from the core, Ba/Ca increased rapidly and remained high in all otoliths. High and unstable Sr/Ca ratios were attributed to estuarine residency, whereas low and stable Sr/Ca ratios were attributed to freshwater residency. These chemical signatures inferred that following recruitment to rivers, some fish remained in the estuary, while others moved upstream. Some individuals shared their time between fresh and brackish waters later in life. The findings of this study have important implications for the protection of nearshore, brackish and freshwater environments for the conservation of this French Polynesian diadromous species. 相似文献
9.
Christophe Tastet Florence Val Michel Lesage Lionel Renault Laurent Marché Michel Bossis Didier Mugniéry 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(8):821-832
Two major proteins, Mcf-A67 and Mcf-B66, were identified by mini two-dimensional polyacrylamide gel electrophoresis in order to distinguish the two European quarantine root-knot nematodes, Meloidogyne chitwoodi and M. fallax, from eight other species. These quarantine proteinic markers have been microsequenced after enzymatic digestion. The internal amino acid sequences exhibit similarities to members of a family of low molecular weight intracellular lipid-binding proteins. Moreover, to explore a simple, rapid, and inexpensive way to identify the two quarantine nematodes, dot blot hybridizations were performed using an antiserum (A67) produced from the longest amino-acid sequence of the protein Mcf-A67. Although several proteins stained on the M. chitwoodi and M. fallax western blot membranes, the two nematodes were easily distinguished from other root-knot nematodes, on dot blot assays with soluble proteins extracted from a single female. Because of its specificity and sensitivity, the use of the A67 antiserum to improve the diagnosis of the two European quarantine root-knot nematodes is discussed. 相似文献
10.
Denoyes-Rothan B Guérin G Délye C Smith B Minz D Maymon M Freeman S 《Phytopathology》2003,93(2):219-228
ABSTRACT Ninety-five isolates of Colletotrichum including 81 isolates of C. acutatum (62 from strawberry) and 14 isolates of C. gloeosporioides (13 from strawberry) were characterized by various molecular methods and pathogenicity tests. Results based on random amplified polymorphic DNA (RAPD) polymorphism and internal transcribed spacer (ITS) 2 sequence data provided clear genetic evidence of two subgroups in C. acutatum. The first subgroup, characterized as CA-clonal, included only isolates from strawberry and exhibited identical RAPD patterns and nearly identical ITS2 sequence analysis. A larger genetic group, CA-variable, included isolates from various hosts and exhibited variable RAPD patterns and divergent ITS2 sequence analysis. Within the C. acutatum population isolated from strawberry, the CA-clonal group is prevalent in Europe (54 isolates of 62). A subset of European C. acutatum isolates isolated from strawberry and representing the CA-clonal and CA-variable groups was assigned to two pathogenicity groups. No correlation could be drawn between genetic and pathogenicity groups. On the basis of molecular data, it is proposed that the CA-clonal subgroup contains closely related, highly virulent C. acutatum isolates that may have developed host specialization to strawberry. C. gloeosporioides isolates from Europe, which were rarely observed were either slightly or nonpathogenic on strawberry. The absence of correlation between genetic polymorphism and geographical origin in Colletotrichum spp. suggests a worldwide dissemination of isolates, probably through international plant exchanges. 相似文献