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1.
Vitamin E supplementation has become a common procedure to promote growth and health and improve the qualitative characteristics of farm animals. It has been demonstrated to be an efficient strategy for improving their reproductive function. Germ cells are particularly vulnerable to oxidative damage and may thus require additional antioxidant protection. The aim of this review is to give a comprehensive overview of the current knowledge of the biochemistry and physiology of vitamin E; successively, the effect of this compound on the reproductive activity of rabbit buck is accurately described. In particular, this review examines studies on the effects of animal age, dose and duration of vitamin E supplementation, as well as the co-supplementation with selenium, vitamin C and polyunsaturated fatty acids. Several investigations have shown beneficial effects in bucks supplemented with vitamin E levels higher than the standard dietary requirement (50 mg/kg) particularly when the semen is stored. However, the exact dietary intake of vitamin E should be decided according to specific tissue needs for the individual vitamin E forms and the specific saturation markers. 相似文献
2.
Abstract – A phylogeographic study of rudd Scardinius erythrophthalmus L. (Pisces: cyprinidae) was addressed to determine the differentiation of Italian populations in relation to the presence of mountain barriers, which identify two biogeographic districts (Padano-Venetian, Tuscano-Latium). At this scope, 409 bp long sequences of mtDNa cytochrome b gene were obtained from Italian and central European samples. Italian rudds phylogeny showed low level of divergence which although resulted from the central European haplotypes. The genetic structure of haplotypes in the studied districts revealed a significant recent fragmentation event. The Padano-Venetian populations showed patterns of past range expansion caused by the specie dispersion by river connections occurred during Pleistocene. This pattern provides evidence for (i) the role of Alps as a barrier for rudd dispersion; (ii) a significant genetic structure among the studied districts related to recent isolation events by the Apennine barrier; (iii) the role of Pleistocene sea level variations in determining phylogeography of the Padano-Venetian populations. 相似文献
3.
D.J. McKenzie G. Piraccini N. Papini C. Galli P. Bronzi C.G. Bolis E.W. Taylor 《Fish physiology and biochemistry》1997,16(5):365-379
The effects of one year's feeding with diets enriched either in highly unsaturated fatty acids of the w3 series (w3 HUFA)
(fish oil-supplemented diet, FOD) or in saturated fatty acids (SFA) (coconut oil-supplemented diet, COD) on fatty acid composition
of tissue lipids, on patterns of resting oxygen consumption and on responses to hypoxia and hypercapnia were investigated
in the Adriatic sturgeon (Acipenser naccarii). FOD sturgeon had higher levels of w3 HUFA in liver and muscle lipids than COD
fish, which had higher levels of SFA. A frequency distribution of instantaneous oxygen uptake rates (M]O2), as measured every
10 min for 8 h, revealed a different pattern of resting oxygen consumption between the two groups. The FOD sturgeon consumed
oxygen in a narrow range of low rates, with a lower mean M]O2 than COD sturgeon, which showed a wide range of more elevated
rates. FOD sturgeon had a lower opercular pressure amplitude than COD fish in normoxia. Exposure to three levels of hypoxia
PO2s = 10.8±0.2; 6.6±0.2 and 4.6±0.2 kPa) or mild hypercapnia (PCO2 = 1.0±0.2 kPa) did not affect ventilation in FOD fish
but elicited hyperventilation in COD animals. Mild hypoxia (PO2 = 10.8±0.2 kPa) and hypercapnia caused less reduction in blood
oxygen content in FOD as compared with COD sturgeon. The effects of adding vitamin E supplements to the diets was investigated;
groups fed vitamin E supplements had elevated M]O2 and hyperventilated in hypoxia. The data indicate that dietary fatty acid
composition influences resting M]O2 in sturgeon and that this influences the regulation of ventilation and blood O2 levels
in hypoxia and hypercapnia. The low resting M]O2 of fish fed w3 HUFA supplements (the FOD group) obviated the need for hyperventilation
in hypoxia or hypercapnia, thereby making them less sensitive to these stresses than sturgeon fed SFA (COD group) or sturgeon
fed either diet supplemented with vitamin E.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
意大利冷冻精液质量的官方监控 总被引:1,自引:0,他引:1
1991年1月15日,意大利政府公布了动物生产法,即法律30(legge30),全面介绍了动物生殖细胞生产中心应具备的条件、建立养殖场的要求和动物繁殖的规章制度。1994年1月13日,意大利农业部依据法律30发布了第172号部长令,详细说明了自然交配、人工授精和胚胎移植的规章制度。部长令规定,意大利任何冻精生产中心(简称中心)生产的冻精或从国外引入的冻精,必须至少取出精液生产批次10%的样品,进行官方检测。司拜伦谨尼研究所(简称研究所)是意大利农业部委托的唯一的执行机构,检测的最后结果是:比较研究所… 相似文献
5.
The mechanisms that determine how folding attempts are interrupted to target folding-incompetent proteins for endoplasmic reticulum-associated degradation (ERAD) are poorly defined. Here the alpha-mannosidase I-like protein EDEM was shown to extract misfolded glycoproteins, but not glycoproteins undergoing productive folding, from the calnexin cycle. EDEM overexpression resulted in faster release of folding-incompetent proteins from the calnexin cycle and earlier onset of degradation, whereas EDEM down-regulation prolonged folding attempts and delayed ERAD. Up-regulation of EDEM during ER stress may promote cell recovery by clearing the calnexin cycle and by accelerating ERAD of terminally misfolded polypeptides. 相似文献
6.
Adult human brain contains cholestanol and two series of cholesterol precursors having 30, 29, 28, and 27 carbon atoms; one has an unsaturated steroid nucleus, and the other is unsaturated in both nucleus and side chain. The ability of preparations of brain to incorporate a specific precursor into cholesterol, as well as into these sterol metabolites in vitro, indicates that cholesterol synthesis continues long after brain maturation ceases. 相似文献
7.
Anna Arnoldi Eliseo Betto Gandolfina Farina Attilio Formigoni Remo Galli Alberto Griffini 《Pest management science》1982,13(6):670-678
Thirty-two 3-phenyl-1-monosubstituted(or 1, 1-disubstituted)prop-2-yn-1-ols, mostly with heterocyclic substituents, and four derivatives, were synthesised and tested in vivo against eight fungal plant pathogens of different taxonomic classes. No compound showed a wide spectrum of activity, however, nine of them were effective against Sphaerotheca fuliginea on Cucumis sativus, both in direct protectant tests and in systemic protectant tests by root application. 相似文献
8.
Wilson DS Teagle DA Alt JC Banerjee NR Umino S Miyashita S Acton GD Anma R Barr SR Belghoul A Carlut J Christie DM Coggon RM Cooper KM Cordier C Crispini L Durand SR Einaudi F Galli L Gao Y Geldmacher J Gilbert LA Hayman NW Herrero-Bervera E Hirano N Holter S Ingle S Jiang S Kalberkamp U Kerneklian M Koepke J Laverne C Vasquez HL Maclennan J Morgan S Neo N Nichols HJ Park SH Reichow MK Sakuyama T Sano T Sandwell R Scheibner B Smith-Duque CE Swift SA Tartarotti P Tikku AA Tominaga M Veloso EA 《Science (New York, N.Y.)》2006,312(5776):1016-1020
Sampling an intact sequence of oceanic crust through lavas, dikes, and gabbros is necessary to advance the understanding of the formation and evolution of crust formed at mid-ocean ridges, but it has been an elusive goal of scientific ocean drilling for decades. Recent drilling in the eastern Pacific Ocean in Hole 1256D reached gabbro within seismic layer 2, 1157 meters into crust formed at a superfast spreading rate. The gabbros are the crystallized melt lenses that formed beneath a mid-ocean ridge. The depth at which gabbro was reached confirms predictions extrapolated from seismic experiments at modern mid-ocean ridges: Melt lenses occur at shallower depths at faster spreading rates. The gabbros intrude metamorphosed sheeted dikes and have compositions similar to the overlying lavas, precluding formation of the cumulate lower oceanic crust from melt lenses so far penetrated by Hole 1256D. 相似文献
9.
10.
Zarankiewicz T Madej J Galli J Bajzert J Stefaniak T 《Polish journal of veterinary sciences》2012,15(2):373-378
Histophilus somni is an opportunistic pathogen causing respiratory, genitourinary and generalized infections in cattle. An important virulence factor is its ability to produce a biofilm. The aim of this work was to confirm that H. somni Hsp60 (Gro-EL) is a constituent of the biofilm produced by this bacterium in vitro and to check whether or not the presence of a specific antibody within the culture medium can inhibit biofilm production. Biofilm production by H. somni cultured in vitro was confirmed by crystalline violet staining. The presence of Hsp60 in the biofilm was confirmed by using specific antibodies produced in a mouse and goat hyperimmunized with H. somni recombinant Hsp60 (rHsp60). Large complexes of biofilm stained with Hsp60 antibodies were microscopically detected. This indicates that the Hsp60 protein is a common constituent of the biofilm produced by H. somni in vitro. In a second experiment, mouse serum containing anti-H. somni rHsp60 antibodies was added to an H. somni culture. It was found that the presence of anti-rHsp60 antibodies in the culture medium inhibited biofilm production in vitro. Only small biofilm particles were seen in the presence of the specific antibody, whereas in control cultures (without specific antiserum) large biofilm complexes were produced. The results indicate that antibodies specific to Hsp60 may be useful for preventing H. somni biofilm formation in vitro. If this also occurs in vivo, it may be helpful for eradicating H. somni infection in cattle through the elimination of carriers. Further in vivo studies are needed to confirm this idea. 相似文献