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Oregano improves reproductive performance of sows 总被引:1,自引:0,他引:1
Natural herbs are being explored as alternatives to antimicrobials. The objective of the present study was to determine the effect of strategic addition of oregano to prefarrowing and lactation diets of sows under field conditions. Alternate farrowing groups were given diets containing 1000 ppm oregano (dried leaf and flower of Origanum vulgare, enriched with 500 g/kg of cold-pressed essential oils of O. vulgare) in prefarrowing and lactation diets. Overall, 801 oregano-treated sows, including 601 primiparous and 1200 multiparous (parity 2.99 +/- 0.43, mean +/- S.E.) and 1809 untreated control sows (705 primiparous and 1104 multiparous; parity 3.04 +/- 0.38), were used. Sows fed oregano had lower annual sow mortality rate (4.02 +/- 0.4% versus 6.92 +/- 1.11%, mean +/- S.E.; P = 0.003), lower sow culling rate during lactation (8.01 +/- 1.11% versus 14.02 +/- 1.33%, P = 0.02), increased farrowing rate (77.02 +/- 2.31% versus 69.91 +/- 2.32%, P = 0.01), increased number of liveborn piglets per litter (10.49 +/- 1.5 versus 9.95 +/- 1.22, P < 0.05), and decreased stillbirth rate (0.909 +/- 0.01 versus 0.807 +/- 0.01, P = 0.05). In addition, multiparous sows fed oregano had higher (P = 0.04) daily voluntary feed intake compared to non-treated sows (7.7 +/- 0.32 kg versus 7.0 +/- 0.42 kg, P = 0.04). Additional studies are needed to elucidate the effects of oregano on the gastrointestinal, immune and urogenital system in swine and to determine if it has any adverse effects. 相似文献
125.
Reversibly permeabilized cells have been used to visualize interphase chromatin structures in the presence and absence of biotinylated nucleotides. By reversing permeabilization, it was possible to confirm the existence of a flexible chromatin folding pattern through a series of transient geometric forms such as supercoiled, circular forms, chromatin bodies, thin and thick fibers, and elongated chromosomes. Our results show that the incorporation of biotin-11-dUTP interferes with chromatin condensation, leading to the accumulation of decondensed chromatin structures. Chromatin condensation without nucleotide incorporation was also studied in cell populations synchronized by centrifugal elutriation. After reversal of permeabilization, nuclei were isolated and chromatin structures were visualized after DAPI staining by fluorescent microscopy. Decondensed veil-like structures were observed in the early S phase (at an average C-value of 2.21), supercoiled chromatin later in the early S (2, 55 C), fibrous structures in the early mid S phase (2, 76 C), ribboned structures in the mid-S phase (2, 98 C), continuous chromatin strings later in the mid-S phase (3,28), elongated prechromosomes in the late S-phase (3, 72 C), precondensed chromosomes at the end and after the S phase (3, 99 C). Fluorescent microscopy revealed that neither interphase nor metaphase chromosomes are separate entities but form a linear array arranged in a semicircle. Linear arrangement was confirmed by computer image analysis. 相似文献
126.
Sharma V Narayanan A Rengachari T Temes GC Chaplen F Moon UK 《Biosensors & bioelectronics》2005,20(11):2218-2227
Fish chromatophores have been shown to be promising biosensors for the detection of hostile agents in the environment. However, state-of-art methods for such applications are still based on extensive use of data/signal processing, in conjunction with need for a skilled human observer to carry out the detection. As a result, conventional methods are complex, costly and cumbersome rendering them useless for field applications requiring low-cost portable solutions capable of fast detection. A new technique is proposed based on the popular scheme of observing the aggregation response in chromatophores for detection of toxicity, and a solution using optical detection and electronic processing is outlined. This scheme has the advantage of being low in cost while providing simple, fast and reliable detection. 相似文献
127.
Gabor?Doka Roland?HischierEmail author 《The International Journal of Life Cycle Assessment》2005,10(1):77-84
Goal, Scope and Background The disposal phase of a product’s life cycle in LCA is often neglected or based on coarse indicators like ‘kilogram waste’. The goal of report No. 13 of the ecoinvent project (Doka 2003) is to create detailed Life Cycle Inventories of waste disposal processes. The purpose of this paper is to give an overview of the models behind the waste disposal inventories in ecoinvent, to present exemplary results and to discuss the assessment of long-term emissions. This paper does not present a particular LCA study. Inventories are compiled for many different materials and various disposal technologies. Considered disposal technologies are municipal incineration and different landfill types, including sanitary landfills, hazardous waste incineration, waste deposits in deep salt mines, surface spreading of sludges, municipal wastewater treatment, and building dismantling. The inventoried technologies are largely based on Swiss plants. Inventories can be used for assessment of the disposal of common, generic waste materials like paper, plastics, packaging etc. Inventories are also used within the ecoinvent database itself to inventory the disposal of specific wastes generated during the production phase. Inventories relate as far as possible to the specific chemical composition of the waste material (waste-specific burdens). Certain expenditures are not related to the waste composition and are inventoried with average values (process-specific burdens). Methods The disposal models are based on previous work, partly used in earlier versions of ecoinvent/ETH LCI data. Important improvements were the extension of the number of considered chemical elements to 41 throughout all disposal models and new landfill models based on field data. New inventories are compiled for waste deposits in deep salt mines and building material disposal. Along with the ecoinvent data and the reports, also Excel-based software tools were created, which allow ecoinvent members to calculate waste disposal inventories from arbitrary waste compositions. The modelling of long-term emissions from landfills is a crucial part in any waste disposal process. In ecoinvent long-term emissions are defined as emissions occurring 100 years after present. They are reported in separate emission categories. The landfill inventories include long-term emissions with a time horizon of 60’000 years after present. Results and Discussion As in earlier studies, the landfills prove to be generally relevant disposal processes, as also incineration and wastewater treatment processes produce landfilled wastes. Heavy metals tend to concentrate in landfills and are washed out to a varying degree over time. Long-term emissions usually represent an important burden from landfills. Comparisons between burdens from production of materials and the burdens from their disposal show that disposal has a certain relevance. Conclusion The disposal phase should by default be included in LCA studies. The use of a material not only necessitates its production, but also requires its disposal. The created inventories and user tools facilitate heeding the disposal phase with a similar level of detail as production processes. The risk of LCA-based decisions shifting burdens from the production or use phase to the disposal phase because of data gaps can therefore be diminished. Recommendation and Perspective Future improvements should include the modelling of metal ore refining waste (tailings) which is currently neglected in ecoinvent, but is likely to be relevant for metals production. The disposal technologies considered here are those of developed Western countries. Disposal in other parts of the World can differ distinctly, for logistic, climatic and economic reasons. The cross-examination of landfill models to LCIA soil fate models could be advantageous. Currently only chemical elements, like copper, zinc, nitrogen etc. are heeded by the disposal models. A possible extension could be the modelling of the behaviour of chemical compounds, like dioxins or other hydrocarbons. 相似文献
128.
An alpha/beta-fold C--C bond hydrolase is involved in a central step of nicotine catabolism by Arthrobacter nicotinovorans 下载免费PDF全文
The enzyme catalyzing the hydrolytic cleavage of 2,6-dihydroxypseudooxynicotine to 2,6-dihydroxypyridine and gamma-N-methylaminobutyrate was found to be encoded on pAO1 of Arthrobacter nicotinovorans. The new enzyme answers an old question about nicotine catabolism and may be the first C--C bond hydrolase that is involved in the biodegradation of a heterocyclic compound. 相似文献
129.
The novel Drosophila tim(blind) mutation affects behavioral rhythms but not periodic eclosion 下载免费PDF全文
Circadian clock function depends on the tightly regulated exclusion or presence of clock proteins within the nucleus. A newly induced long-period timeless mutant, tim(blind), encodes a constitutively hypophosphorylated TIM protein. The mutant protein is not properly degraded by light, and tim(blind) flies show abnormal behavioral responses to light pulses. This is probably caused by impaired nuclear accumulation of TIM(BLIND) protein, which we observed in brain pacemaker neurons and photoreceptor cells of the compound eye. tim(blind) encodes two closely spaced amino acid changes compared to the wild-type TIM protein; one of them is within a putative nuclear export signal of TIM. Under constant conditions, tim(blind) flies exhibit 26-hr free-running locomotor rhythms, which are not correlated with a period lengthening of eclosion rhythms and period-luciferase reporter-gene oscillations. Therefore it seems possible that TIM--in addition to its well-established role as core clock factor--functions as a clock output factor, involved in determining the period length of adult locomotor rhythms. 相似文献
130.
Absence of the RGS9.Gbeta5 GTPase-activating complex in photoreceptors of the R9AP knockout mouse 总被引:1,自引:0,他引:1
Keresztes G Martemyanov KA Krispel CM Mutai H Yoo PJ Maison SF Burns ME Arshavsky VY Heller S 《The Journal of biological chemistry》2004,279(3):1581-1584
Timely termination of the light response in retinal photoreceptors requires rapid inactivation of the G protein transducin. This is achieved through the stimulation of transducin GTPase activity by the complex of the ninth member of the regulator of G protein signaling protein family (RGS9) with type 5 G protein beta subunit (Gbeta5). RGS9.Gbeta5 is anchored to photoreceptor disc membranes by the transmembrane protein, R9AP. In this study, we analyzed visual signaling in the rods of R9AP knockout mice. We found that light responses from R9AP knockout rods were very slow to recover and were indistinguishable from those of RGS9 or Gbeta5 knockout rods. This effect was a consequence of the complete absence of any detectable RGS9 from the retinas of R9AP knockout mice. On the other hand, the level of RGS9 mRNA was not affected by the knockout. These data indicate that in photoreceptors R9AP determines the stability of the RGS9.Gbeta5 complex, and therefore all three proteins, RGS9, Gbeta5 , and R9AP, are obligate members of the regulatory complex that speeds the rate at which transducin hydrolyzes GTP. 相似文献