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51.
Pawel Antoni Kolodziejski Maciej Sassek Daniela Chalupka Natalia Leciejewska Leszek Nogowski Pawel Mackowiak Damian Jozefiak Katarzyna Stadnicka Maria Siwek Marek Bednarczyk Tomasz Szwaczkowski Ewa Pruszynska-Oszmalek 《畜牧与生物技术杂志(英文版)》2018,(2)
Background: In order to discover new strategies to replace antibiotics in the post-antibiotic era in meat-type chicken production, two new synbiotics were tested:(Lactobacillus salivarius IBB3154 plus galactooligosaccharide(Syn1) and Lactobacillus plantarum IBB3036 plus raffinose family oligosaccharides(Syn2).Methods: The synbiotics were administered via syringe, using a special automatic system, into the egg air chamber of Cobb 500 broiler chicks on the 12 thday of egg incubation(2 mg of prebiotics + 105 cfu bacteria per egg).Hatched roosters(total 2,400) were reared on an experimental farm, kept in pens(75 animals per pen), with free access to feed and water. After 42 d animals were slaughtered. Blood serum, pancreas, duodenum and duodenum content were collected.Results: Syn2 increased trypsin activity by 2.5-fold in the pancreas and 1.5-fold in the duodenal content. In the duodenum content, Syn2 resulted in ca 30% elevation in lipase activity and 70% reduction in amylase activity.Syn1 and Syn2 strongly decreased expression of m RNA for GLP-1 and GIP in the duodenum and for GLP-1 receptors in the pancreas. Simultaneously, concentrations of the incretins significantly diminished in the blood serum(P 0.05). The decreased expression of incretins coincides with changed activity of digestive enzymes in the pancreas and in the duodenal content. The results indicate that incretins are involved in the action of Syn1 and Syn2 or that they may even be their target. No changes were observed in key hormones regulating metabolism(insulin, glucagon, corticosterone, thyroid hormones, and leptin) or in metabolic indices(glucose,NEFA, triglycerides, cholesterol). Additionally, synbiotics did not cause significant changes in the activities of alanine and aspartate aminotransferases in broiler chickens. Simultaneously, the activity of alkaline phosphatase and gamma glutamyl transferase diminished after Syn2 and Syn1, respectively.Conclusion: The selected synbiotics may be used as in ovo additives for broiler chickens, and Syn2 seems to improve their potential digestive proteolytic and lipolytic ability. Our results suggest that synbiotics can be directly or indirectly involved in incretin secretion and reception. 相似文献
52.
Janina Skipor Marta Kowalewska Aleksandra Szczepkowska Anna Majewska Tomasz Misztal Marek Jalynski Andrzej P.Herman Katarzyna Zabek 《畜牧与生物技术杂志(英文版)》2018,(1)
Background: Interleukin-1β(IL-1β) is important mediator of inflammatory-induced suppression of reproductive axis at the hypothalamic level. At the beginning of inflammation, the main source of cytokines in the cerebrospinal fluid(CSF) is peripheral circulation, while over time, cytokines produced in the brain are more important. Melatonin has been shown to decrease pro-inflammatory cytokines concentration in the brain. In ewes, melatonin is used to advance the onset of a breading season. Little is known about CSF concentration of IL-1β in ewes and its correlation with plasma during inflammation as well as melatonin action on the concentration of IL-1β in blood plasma and the CSF, and brain barriers permeability in early stage of lipopolysaccharide(LPS)-induced inflammation.Methods: Systemic inflammation was induced through LPS administration in melatonin-and sham-implanted ewes. Blood and CSF samples were collected before and after LPS administration and IL-1β and albumin concentration were measured. To assess the functions of brain barriers albumin quotient(QAlb) was used.Expression of IL-1β(Il1B) and its receptor type Ⅰ(Il1r1) and type Ⅱ(Il1r2) and matrix metalloproteinase(Mmp) 3 and 9 was evaluated in the choroid plexus(CP).Results: Before LPS administration, IL-1β was on the level of 62.0 ± 29.7 pg/mL and 66.4 ± 32.1 pg/mL in plasma and 26.2 ± 5.4 pg/mL and 21.3 ± 8.7 pg/mL in the CSF in sham-and melatonin-implanted group, respectively.Following LPS it increased to 159.3 ± 53.1 pg/mL and 197.8 ± 42.8 pg/mL in plasma and 129.8 ± 54.2 pg/mL and139.6 ± 51.5 pg/mL in the CSF. No correlations was found between plasma and CSF IL-1β concentration after LPS in both groups. The QAlb calculated before LPS and 6 h after was similar in all groups. Melatonin did not affected m RNA expression of Il1B, Il1r1 and Il1r2 in the CP. The m RNA expression of Mmp3 and Mmp9 was not detected.Conclusions: The lack of correlation between plasma and CSF IL-1β concentration indicates that at the beginning of inflammation the local synthesis of IL-1β in the CP is an important source of IL-1β in the CSF. Melatonin from slow-release implants does not affect IL-1β concentration in plasma and CSF in early stage of systemic inflammation. 相似文献
53.
Effects of prostaglandin F(2alpha) and nitric oxide on the secretory function of bovine luteal cells 总被引:1,自引:0,他引:1
Korzekwa A Jaroszewski JJ Bogacki M Deptula KM Maslanka TS Acosta TJ Okuda K Skarzynski DJ 《The Journal of reproduction and development》2004,50(4):411-417
The objective of the present study was to investigate the influence of prostaglandin F(2alpha) (PGF (2alpha)) and nitric oxide (NO) on production of steroids and PGs by culturing bovine luteal cells obtained from ovaries on days 8-12 of the estrous cycle with a nitric oxide (NO) donor (Spermine NONOate), and a NO synthase inhibitor (N(G)-nitro-L-arginine methyl ester dihydrochloride: L-NAME). When the cells were exposed for 24 h to PGF(2alpha) (10(-7)-10(-5) M), production of progesterone (P(4)) increased significantly at all doses used (P<0.05). Moreover, PGF(2alpha) stimulated PGF(2alpha) production (P<0.01), depressed testosterone (T) production (P<0.05), but did not affect synthesis of prostaglandin E(2) (PGE(2)). Spermine NONOate decreased P(4) production to 66%, 47% and 34% of the control concentration after treatment with 10(-5) M, 10(-4) M and 10(-3) M, respectively, but did not affect T production, and increased PGF(2alpha) synthesis (P<0.05) and PGE(2) (P<0.01) at all doses used. L-NAME increased production of P(4) (P<0.01) but did not affect (P>0.05) secretion of T, PGF(2alpha) and PGE(2). Estradiol-17beta (E(2)) was detectable on the level of sensitivity of assay and was not significantly altered by any treatments. The overall results suggest that PGF(2alpha) and NO produced locally in bovine CL play roles in the regulation of the secretory function of the bovine CL as auto/paracrine factors. 相似文献
54.
Assessment of the impact of climate change on the latency period of leaf rust on triticale in Poland
Andrzej Wójtowicz Marek Wójtowicz Roland Sigvald Bartosz Czernecki Henryk Ratajkiewicz Agnieszka Łacka 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(3):195-207
ABSTRACTDisease development in plants is strongly dependent on weather conditions, with temperature playing a particularly significant role by influencing latency period duration. Using two models describing the relationship between latency period and temperature, we performed simulations aimed at predicting changes in the latency period of leaf rust (Puccina recondita f. sp. tritici) on triticale in response to expected climate change. The simulations were based on meteorological data recorded in the period 1986–2005 at locations representing 16 provinces in Poland and based on values obtained after transformation of the observed data to reflect temperature changes under four scenarios (RCP2.6, RCP4.5, RCP6.0 and RCP8.5) according to the giss_e2_r climate model. In all scenarios, the results for the two triticale cultivars studied, Witon (vulnerable to P. recondita) and Gniewko (less susceptible), showed a threat of faster development (shorter leaf rust latency period) on triticale triggered by climate change in south-east and south-central Poland than in other regions. The results also showed an increased probability of future regional diversification of leaf rust latency period duration on vulnerable triticale cultivars, opportunities for earlier start of leaf rust epidemics on triticale in Poland and an increase in ?nal disease severity in comparison with 1986–2005. 相似文献
55.
Modular green roofs were investigated to better understand surface and membrane level temperature expectations of unirrigated green roofs during hot summer conditions in south-central Texas. We used three succulent monocultures, Sedum kamtschaticum, Delosperma cooperi, Talinum calycinum syn. Phemeranthus calycinus and one unplanted control module, each replicated 3 times. Media surface and below media temperatures were monitored, as well as soil water content and general weather conditions (RH, air temperature). Temperatures at the surface and below the media surface were compared with temperatures of a standard roof surface. We found that diurnal surface temperature reductions were very stable throughout the summer. Much larger temperature reductions were achieved below the modules than at the soil surface. Temperature reductions at the soil surface were predominantly driven by soil volumetric water content (VWC) and, to a lesser degree, air temperature while species and percent cover had small modifying effects through interactions with VWC and air temperature. Temperature reductions below the modules were driven by surface soil temperature, while increasing VWC led to a small decrease in temperature reductions at the membrane level. Mean daily temperature reductions achieved were 18.0 °C at the soil surface and 27.5 °C below the module, thus demonstrating that unirrigated, succulent-based green roofs can provide significant rooftop temperature reductions during hot, dry summer conditions. 相似文献
56.
Mariusz Czop Jacek Motyka Ondra Sracek Marek Szuwarzy��ski 《Water, air, and soil pollution》2011,214(1-4):423-434
The Gorka pit lake was formed in an inactive Jurassic limestone quarry after cessation of open-pit dewatering. The main problem of the water quality in this area is linked to a large volume of extremely alkaline leachate disposed in the flooded quarry. The lake is meromictic due to a large density contrast between shallow and deep water layers. Water in the lake is of the Na?CCO3?COH type, pH is in the range from 11.5 to 13.3, and there are high concentrations of sulfate and several toxic elements (Al, As, Cr, Mo, P, and V). The chemical composition of the extremely alkaline leachate was formed as a result of the groundwater interaction with the industrial red mud wastes containing 5?C10 wt.% of sodium carbonate. There is a trend of increasing concentrations and pH values with depth, mainly due to the in-gassing of atmospheric CO2 into the surface layer and due to density stratification in the water column. Similar stratification is observed in groundwater wells around the lake. High dissolved concentrations of oxyanionic contaminants such as As, Cr, and V are caused by their high mobility and desorption under extremely alkaline conditions. In spite of reducing conditions at the bottom of the lake, caused by high concentrations of dumped organic matter, sulfate behaves conservatively because sulfate reducing bacteria do not survive in this pH range. 相似文献
57.
The role of Ca2+ and Na+ membrane transport in brook trout (Salvelinus fontinalis) spermatozoa motility 总被引:1,自引:0,他引:1
Olga Bondarenko Borys Dzyuba Jacky Cosson Marek Rodina Otomar Linhart 《Fish physiology and biochemistry》2014,40(5):1417-1421
The role of environmental ion composition and osmolality in Ca2+ signaled activation was assessed in spermatozoa of brook trout Salvelinus fontinalis. Milt from ten mature males was obtained by abdominal massage. Spermatozoa motility was evaluated in 0, 100, and 300 mOsm/kg NaCl or sucrose solutions, buffered by 10 mM Tris–HCl pH 8.5. For investigation of spermatozoa reaction to external Ca2+ concentration, 2 mM ethylene glycol tetraacetic acid (EGTA) was added to the activation media as a calcium ions chelator. For investigation of the effect of external Na+ concentration in conditions of low external Ca2+, 100 µM amiloride was added to the EGTA-containing solutions as a Na+ transport blocker. Low motility was observed in sucrose (Na+ free) solutions containing 2 mM EGTA but not in Na+ solutions containing 2 mM EGTA. Addition of amiloride led to significantly increased motility (P < 0.05) compared with sucrose (Na+ free) solutions containing 2 mM EGTA. We conclude that Na+ transport in Ca2+-free solutions plays a regulatory role in brook trout spermatozoa activation. The influence of competitive Na+ and Ca2+ transport on the control of spermatozoa activation requires further study with respect to its application for improvement of artificial activation and storage media. 相似文献
58.
59.
Wood specific gravity was determined for 29 half-sib families of 4-year-old Pinus tecunumanii from the Mountain Pine Ridge, Belize, planted at three locations in Brazil and Colombia. Although there was a significant (p 0.05) family by sites interaction (F × S), it was found that only 5 of the 29 families were major contributors. The test planting at the highest elevation (1750 m, La Arcadia, Colombia) was the most interactive site.CAMCORE Cooperative, College of Forest Resources, North Carolina State University 相似文献
60.
Marek Gnatowski Rebecca Ibach Mathew Leung Grace Sun 《Wood material science & engineering》2015,10(1):94-111
AbstractTwo wood plastic composite (WPC) boards, one experimental and one commercial, were exposed to exterior conditions and evaluated non-destructively using a clinical magnetic resonance imaging (MRI) unit for moisture content (MC) and distribution. The experimental board was exposed in Vancouver, British Columbia, for more than 8 years, and the commercial board was exposed near Hilo, Hawaii, for 2 years. Both boards were characterized in terms of wood content, density, water uptake properties and voids content. The experimental board was additionally destructively analysed for water absorption of the WPC and MC calculated based on the wood content for verification of MRI results. MRI detected the presence of free water and its distribution in both of the WPC boards. Fibre saturation in the experimental board was found to be about 22–24%, in comparison to 25–30% present in most wood species. There was good correlation between the detection of free water by MRI and by destructive testing. Magnetic resonance images showed various major points of water entry in the WPC boards such as the support area, the cut ends, the dripping edge and the sides of the boards. For the experimental board, significant water entry also occurred at the upper exposed surface. 相似文献