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Sample records for model protein hen

  1. Storage stability of hen egg white powders in three protein/water dough model systems.

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    Rao, Qinchun; Rocca-Smith, Jeancarlo R; Labuza, Theodore P

    2013-06-01

    In recent years, due to the specific health benefits associated with bioactive peptides and the reduction of protein allergenicity by enzymatic hydrolysis, the utilisation of protein hydrolysates in the intermediate-moisture food (IMF) market, such as high protein nutrition bars (HPNB), has significantly increased. Currently, no reported study is related to the storage stability of dried hen egg white (DEW) and its hydrolysates (HEW) in an IMF matrix. Therefore, three DEW/HEW dough model systems (100%HEW+0%DEW, 75%HEW+25%DEW and 50%HEW+50%DEW) were established using two commercial spray-dried egg white powders to study the effect of temperature and fraction of HEW on these IMF models (water activity (a(w)): ∼0.8). During storage at three different temperatures (23, 35 and 45°C) for 70 days, the selected physicochemical properties of the dough systems were compared. Overall, kinetic analysis showed an apparent zero-order model fit for the change in the colour (L(∗)), fluorescence intensity (FI) and hardness, as a function of time, for different dough model systems. As expected, the L(∗), FI and hardness increased as a function of time mainly due to the Maillard reaction. The amount of free amino groups decreased, with an increase in rate of loss, as temperature increased in the 100%HEW+0%DEW model. When DEW was substituted for some HEW, the regeneration of the free amino groups after loss was observed as a function of time. Furthermore, when the percentage of HEW was decreased, the incidence of mouldy samples occurred sooner, which indicates that HEW has some antimicrobial ability, especially in the 100%HEW+0%DEW system where mould growth did not occur. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Moisture-induced quality changes of hen egg white proteins in a protein/water model system.

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    Rao, Qinchun; Rocca-Smith, Jeancarlo R; Labuza, Theodore P

    2012-10-24

    In recent years, the intermediate-moisture foods (IMF), such as nutrition and energy bars, are a rapidly growing segment of the global food market. However, due to moisture-induced protein aggregation, commercial high protein nutrition bars generally become harder over time, thus losing product acceptability. In this study, the objectives were to investigate the moisture-induced protein aggregation in a hen egg white proteins/water dough model system (water activity (a(w)): 0.95) and to evaluate its molecular mechanisms and controlling factors. During storage at three different temperatures (23, 35, and 45 °C) for 70 days, four selected physicochemical changes of the dough system were analyzed: the a(w), the color (L* value), the fluorescent Maillard compounds (fluorescence intensity (FI) value), and the remaining free amino groups. Overall, the physicochemical changes of egg white proteins in the dough system are closely related to the glass transition temperature (T(g)). The effect of moisture content on both the L* and FI values occurred as a function of storage time at 45 °C due to the Maillard reaction. The change of the remaining free amino groups at different temperatures was derived from the coaction of both the Maillard reaction and enzymatic hydrolysis from molds. Additionally, through analyzing the buffer-soluble egg white proteins using gel electrophoresis, our results showed that moisture-induced aggregates were produced by two chemical reactions during storage: the disulfide interaction and the Maillard reaction. Furthermore, the effect of two processes during manufacturing, desugarization and dry-heat pasteurization, on the physicochemical changes of the egg white proteins was elucidated. In order to prevent or reduce moisture-induced protein aggregation during product storage and distribution, two potential solutions were also discussed.

  3. Modelo para determinar as exigências de proteína para poedeiras Modelling protein utilization in laying hens

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    Nilva Kazue Sakomura

    2002-11-01

    Full Text Available O objetivo do trabalho foi elaborar um modelo para estimar as exigências de proteína bruta (PB para poedeiras leves, usando o método fatorial. Para determinar as exigências de proteína bruta (PB para manutenção foi utilizada a técnica do balanço de nitrogênio. A exigência de proteína bruta para o ganho de peso foi determinada em função do conteúdo de nitrogênio na carcaça e a eficiência de utilização do nitrogênio da dieta. A exigência de PB, para produção de ovos, foi determinada considerando o teor de PB determinado nos ovos e a eficiência de deposição do nitrogênio no ovo. A partir dos valores das exigências para manutenção, para o ganho e produção foi elaborada uma equação para predizer as exigências diárias de PB (g/ ave/ dia para poedeiras: PB = 1,94. P0,75 + 0,48.G + 0,301.O, em que P = peso corporal (kg, G = ganho de peso diário (g/dia e O = massa de ovos produzida (g/ave/dia.The objective of this study was to determine a model for crude protein requirements (CP for laying hen by the factorial method. The protein maintenance requirement was determine by the nitrogen balance technique . The crude protein requirement for weight gain was determined based on body nitrogen content and nitrogen efficiency for body deposition. The crude protein requirement for egg production was determined based on the nitrogen content of eggs and nitrogen efficiency for egg deposition. Considering the requirements for maintenance, egg production and weight gain, it was elaborated a protein requirement model for laying hen: PB = 1.94xW.75 + 0.480xG + 0,301x E, where PB = requirement (g/bird/day, W = body weight (kg, G = daily weight gain (g/day and E = egg mass (g/bird/day.

  4. Characteristics of hydration water around hen egg lysozyme as the protein model in aqueous solution. FTIR spectroscopy and molecular dynamics simulation.

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    Panuszko, Aneta; Wojciechowski, Marek; Bruździak, Piotr; Rakowska, Paulina W; Stangret, Janusz

    2012-12-05

    In this paper, the hydration of a model protein--hen egg white lysozyme in aqueous solution has been presented. The leading method used was FTIR spectroscopy with an application of a technique of semi-heavy water (HDO) isotope dilution. Analysis of spectra of HDO isotopically diluted in water solution of lysozyme allowed us to isolate HDO spectra affected by lysozyme, and thus to characterise the energetic state of water molecules and their arrangement around protein molecules. The number of water molecules and the shape of the affected HDO spectrum were obtained using a classical and a chemometric method. This shape showed that the HDO spectrum affected by lysozyme may be presented as a superposition of two spectra corresponding to HDO affected by N-methylacetamide and the carboxylate anion (of the formic acid). Moreover, based on the difference in intermolecular distances distribution of water molecules (obtained from spectral data), we demonstrated that the lysozyme molecule causes a decrease in population of weak hydrogen bonds, and concurrently increases the probability of an occurrence of short hydrogen bonds in water affected by lysozyme. This conclusion was also confirmed by the molecular dynamics (MD) simulation.

  5. Early postmolt performance of laying hens fed a low-protein corn molt diet supplemented with spent hen meal.

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    Koelkebeck, K W; Parsons, C M; Douglas, M W; Leeper, R W; Jin, S; Wang, X; Zhang, Y; Fernandez, S

    2001-03-01

    We used a total of 504 commercial Single Comb White Leghorn hens (69 and 65 wk of age) in each of two experiments, and hens were induced to molt by feed withdrawal only. Feed withdrawal lasted for 12 and 11 d, and hens lost 26 and 25%, body weight in Experiments 1 and 2, respectively. All hens were then weighed, and seven replicate groups of 12 hens each were assigned to molt diet treatments. In Experiment 1, diets consisted of a corn basal diet (7.9% CP) or corn basal diet supplemented with 7.5 or 10% spent hen meal (SHM) each from two different sources. In Experiment 2, the corn basal diet or this diet supplemented with 5 or 10% SHM alone or 5% SHM plus Met, Lys, and Trp was evaluated. A molt diet of 16% CP corn-soybean meal was used as a positive control in both experiments. Molt diets were fed for 15 d in both experiments, at which time all hens were fed a 16% CP layer diet. Performance was measured for 8 wk following the beginning of feeding the layer diet. Feeding the low-protein corn molt diet supplemented with 5 to 10% SHM improved early postmolt egg production performance and body weight gain compared with hens fed the corn basal diet alone. The 7.5 and 10% SHM diets yielded early postmolt performance that was not significantly different (P > 0.05) from that of hens fed the high-protein (16% CP) diet. Supplementing the 5% SHM diet with amino acids generally did not significantly improve performance. The present study thus indicates that improved early postmolt performance may be achieved by supplementation of a low-protein corn molt diet with 5 to 10% SHM.

  6. A model of Salmonella infection within industrial house hens.

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    Prévost, K; Magal, P; Beaumont, C

    2006-10-07

    Salmonella is one of the major sources of toxi-infection in humans. Incidences of human salmonellosis have greatly increased over the past 20 years and this can largely be attributed to epidemics of Salmonella enteritidis phage type 4 within poultry. The main concern with this bacterium is the existence of silent carriers, i.e. animals harbouring S. enteritidis without expressing any visible symptoms. In this article, we formulate a model for S. enteritidis transmission in hen houses, considering both the hens and the environmental bacterium contamination. By considering the hen's individual development of the disease, we build a model for the production of eggs contaminated by S. enteritidis. The objectives are to analyse the dynamic of the disease, and to provide understanding of measures to avoid the endemicity of S. enteritidis in industrial hen houses.

  7. Effect of four processed animal proteins in the diet on digestibility and performance in laying hens.

    NARCIS (Netherlands)

    Krimpen, van M.M.; Veldkamp, T.; Binnendijk, G.P.; Veer, de R.

    2010-01-01

    An experiment was performed to investigate the effect of animal vs. vegetable protein sources in the diet of laying hens on the development of hen performance. A diet containing protein sources of only vegetable origin was compared with 4 diets, each containing 1 of 4 processed animal proteins (PAP)

  8. Molecular phylogenetics and comparative modeling of HEN1, a methyltransferase involved in plant microRNA biogenesis

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    Obarska Agnieszka

    2006-01-01

    Full Text Available Abstract Background Recently, HEN1 protein from Arabidopsis thaliana was discovered as an essential enzyme in plant microRNA (miRNA biogenesis. HEN1 transfers a methyl group from S-adenosylmethionine to the 2'-OH or 3'-OH group of the last nucleotide of miRNA/miRNA* duplexes produced by the nuclease Dicer. Previously it was found that HEN1 possesses a Rossmann-fold methyltransferase (RFM domain and a long N-terminal extension including a putative double-stranded RNA-binding motif (DSRM. However, little is known about the details of the structure and the mechanism of action of this enzyme, and about its phylogenetic origin. Results Extensive database searches were carried out to identify orthologs and close paralogs of HEN1. Based on the multiple sequence alignment a phylogenetic tree of the HEN1 family was constructed. The fold-recognition approach was used to identify related methyltransferases with experimentally solved structures and to guide the homology modeling of the HEN1 catalytic domain. Additionally, we identified a La-like predicted RNA binding domain located C-terminally to the DSRM domain and a domain with a peptide prolyl cis/trans isomerase (PPIase fold, but without the conserved PPIase active site, located N-terminally to the catalytic domain. Conclusion The bioinformatics analysis revealed that the catalytic domain of HEN1 is not closely related to any known RNA:2'-OH methyltransferases (e.g. to the RrmJ/fibrillarin superfamily, but rather to small-molecule methyltransferases. The structural model was used as a platform to identify the putative active site and substrate-binding residues of HEN and to propose its mechanism of action.

  9. Continual feeding of two types of microalgal biomass affected protein digestion and metabolism in laying hens.

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    Ekmay, R D; Chou, K; Magnuson, A; Lei, X G

    2015-01-01

    A 14-wk study was conducted to determine the nutritional efficacy and ssmetabolic impact of 2 types of microalgal biomass as alternative protein sources in laying hen diets. Shaver hens (total = 150 and 26 wk old) were fed 1 of 5 diets: a control or a defatted green microalgal biomass (DG; Desmodesmus spp.) at 25% and a full-fatted diatom biomass (FD; Staurosira spp.) at 11.7% inclusion with or without protease. This experiment consisted of 5 replicates per treatment and each replicate contained 6 hens individually reared in cages (1 hen for biochemical data/replicate). Despite decreased ADFI (P = 0.03), hens fed DG or FD had final BW, overall hen-day egg production, and egg quality similar to the controls. Feeding DG or FD did not alter plasma concentrations of insulin, glutamine, and uric acid or alkaline phosphatase activity at wk 8 or 14 but decreased plasma 3-methyhistine concentrations (P = 0.03) and tartrate-resistant acid phosphatase (TRAP) activities (P < 0.001) at wk 14 and improved (P = 0.002) ileal total AA digestibility. Although DG or FD exhibited moderate effects on intestinal brush border protease activities and mRNA levels of duodenal transporters Pept1, Lat1, and Cat1, both substantially enhanced (P < 0.05) phosphorylation of hepatic protein synthesis key regulator S6 ribosomal protein (S6) and the ratio of phospho-S6 to S6 in the liver of hens. However, DG and FD manifested with different impacts on weights of egg and egg albumen, proteolytic activity of jejunal digesta, plasma TRAP activity, ileal total AA digestibility, and several intestinal genes and hepatic proteins. Supplemental protease in the DG and FD diets produced mixed effects on a number of measures. In conclusion, our findings revealed the feasibility of including greater levels of microalgal biomass as a source of feed protein for laying hens and a novel potential of the biomass in improving dietary protein digestion and body protein metabolism than previously perceived.

  10. A natural and readily available crowding agent: NMR studies of proteins in hen egg white.

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    Martorell, Gabriel; Adrover, Miquel; Kelly, Geoff; Temussi, Piero Andrea; Pastore, Annalisa

    2011-05-01

    In vitro studies of biological macromolecules are usually performed in dilute, buffered solutions containing one or just a few different biological macromolecules. Under these conditions, the interactions among molecules are diffusion limited. On the contrary, in living systems, macromolecules of a given type are surrounded by many others, at very high total concentrations. In the last few years, there has been an increasing effort to study biological macromolecules directly in natural crowded environments, as in intact bacterial cells or by mimicking natural crowding by adding proteins, polysaccharides, or even synthetic polymers. Here, we propose the use of hen egg white (HEW) as a simple natural medium, with all features of the media of crowded cells, that could be used by any researcher without difficulty and inexpensively. We present a study of the stability and dynamics behavior of model proteins in HEW, chosen as a prototypical, readily accessible natural medium that can mimic cytosol. We show that two typical globular proteins, dissolved in HEW, give NMR spectra very similar to those obtained in dilute buffers, although dynamic parameters are clearly affected by the crowded medium. The thermal stability of one of these proteins, measured in a range comprising both heat and cold denaturation, is also similar to that in buffer. Our data open new possibilities to the study of proteins in natural crowded media. Copyright © 2010 Wiley-Liss, Inc.

  11. Tryptophan, threonine and isoleucine supplementation in low-protein diets for commercial laying hens

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    Iván Camilo Ospina Rojas

    2015-06-01

    Full Text Available Isoleucine (Ile, threonine (Thr and tryptophan (Trp are most likely candidates for becoming third limiting amino acids (AA in layer diets. This work studied the effect of supplementing Ile, Thr and Trp in low-protein diets on the productive performance, egg quality and serum parameters of Hy-Line W36 laying hens. A total of 360 30-week-old laying hens were distributed in a completely randomized design into 9 treatments with 5 replications of 8 birds each. Treatments consisted of a control diet that was based on corn and soybean meal formulated with 15.5% CP. A second diet with 13% CP was formulated to meet the requirements for all essential AA of the control diet, except for Ile, Thr and Trp. The other treatments consisted of individual and combined supplementation of the aforementioned AA in the 13% CP diet. The reduction of the dietary protein level negatively influenced (p<0.05 the productivity of the hens, impairing egg production, feed conversion (kg kg-1 and kg dz-1, and egg mass. However, these variables were restored with individual and combined supplementation of the three AA in the 13% CP diet. Individually-supplemented diets with Ile, or combined with Thr and/or Trp, resulted in hens with lower (p<0.05 serum uric acid and ammonia concentrations as compared to birds receiving diets with 15.5% (control and 13% CP. The protein levels can be reduced (13% CP in the diet of commercial laying hens without compromising performance, egg quality or serum parameters with individual Ile, Thr or Trp supplementation.

  12. Reduction of Salmonella Enteritidis in the spleens of hens by bacterins that vary in fimbrial protein SefD.

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    Sanchez-Ingunza, Roxana; Guard, Jean; Morales, Cesar A; Icard, Alan H

    2015-10-01

    The objective of this research was to determine whether variation in the presence of fimbrial protein SefD would impact efficacy of bacterins as measured by recovery of Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) from the spleens of hens. Two bacterins were prepared that varied in SefD content. Also, two adjuvants were tested, namely, water-in-oil and aluminum hydroxide gel (alum). Control groups for both adjuvant preparations included infected nonvaccinated hens and uninfected nonvaccinated hens. At 21 days postinfection, Salmonella Enteritidis was recovered from 69.7%, 53.1%, and 86.0% from the spleens of all hens vaccinated with bacterins lacking SefD, bacterins that included SefD, and infected nonvaccinated control hens, respectively. No Salmonella was recovered from uninfected nonvaccinates. Results from individual trials showed that both bacterins reduced positive spleens, but that the one with SefD was more efficacious. Alum adjuvant had fewer side effects on hens and egg production as compared to water-in-oil. However, adjuvant did not change the relative recovery of Salmonella Enteritidis from spleens. These results suggest that SefD is a promising target antigen for improving the efficacy of immunotherapy in hens, and is intended to reduce Salmonella Enteritidis in the food supply.

  13. Modeling ovarian follicle growth in commercial and heritage Single Comb White Leghorn hens.

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    McLeod, E S; Jalal, M A; Zuidhof, M J

    2014-11-01

    Approximately 84% of the energy in chicken eggs resides in the yolk. A robust model of ovarian follicle development is therefore valuable for estimating energy requirements of laying hens. The current experiment was designed to model the growth of ovarian follicles in 32-wk-old modern commercial line (CL) and unselected heritage line (HL) Single Comb White Leghorn hens. The volume of yolk deposited daily during the rapid growth phase (RGP) was estimated using a double dye technique. For 21 d, 8 CL and 8 HL hens were fed capsules (no. 1) containing Sudan IV (red) and Sudan Black dyes on alternate days. An additional 8 control CL hens were fed empty capsules. Eggs were collected, and the daily volume of yolk deposited was estimated. Significant differences are reported where P hens, respectively. Duration of the RGP was shorter (7.35 d) in the CL hens compared with the HL hens (7.95 d). A nonlinear Lomolino model described follicular weight, which varied between strains over d 2 to 9 of follicle development; at each day during development, follicle weights were higher where RGP were shorter. The volume of yolk deposited for the 8 d preceding oviposition in CL was 0.17, 0.28, 0.43, 0.99, 1.84, 2.47, 2.82, 2.86, and 2.51 cm(3); and in HL was 0.17, 0.33, 0.72, 1.40, 2.15, 2.46, 2.48, 2.32, and 1.93 cm(3). The HL had a higher rate of yolk deposition 7 to 5 d before oviposition, and CL had a higher rate of yolk deposition 3 to 1 d before oviposition with no significant difference between lines on d 4 before oviposition. Although growth patterns differed, there were no differences among lines in final follicle weights (14.1 g) or retained energy (42.4 kcal).

  14. Fast separation of hen egg white protein with a phosphorylcholine type zwitterionic ion chromatography stationary phase

    Institute of Scientific and Technical Information of China (English)

    Qian Qu; Xiu Juan Yu; Xi Wu; Fei Shi; Li Li Wang

    2012-01-01

    In this work,a kind of preparation method of zwitterionic ion chromatography (ZIC) stationary phase modified with phosphorylcholine (PC) was obtained by hydrolyzing after bonding phosphorylcholine dichloride to diol-silica to better explore the characteristics of the PC groups as ZIC stationary phase ligand in simultaneous separation of acidic proteins and basic proteins.The results showed that two kinds of acidic proteins and three kinds of basic proteins can be separated completely,meanwhile,hen egg white was separated and purified and three kinds of egg white components ovalbumin,G2 ovoglobulin and ovotransfemin proteins were separated completely by one single step on PC-ZIC column,the purity of all proteins reached above 95%.PC-ZIC stationary phase was successfully improved with better separation capacity and selectivity than previously reported in this paper.

  15. Effect of dietary protein sources on production performance, egg quality, and plasma parameters of laying hens

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    Wang, Xiaocui; Zhang, Haijun; Wang, Hao; Wang, Jing; Wu, Shugeng; Qi, Guanghai

    2017-01-01

    Objective This study was conducted to evaluate the effects of dietary protein sources (soybean meal, SBM; low-gossypol cottonseed meal, LCSM; double-zero rapeseed meal, DRM) on laying performance, egg quality, and plasma parameters of laying hens. Methods A total of 432 32-wk-old laying hens were randomly divided into 6 treatments with 6 replicates of 12 birds each. The birds were fed diets containing SBM, LCSM100, or DRM100 individually or in combination with an equal amount of crude protein (CP) (LCSM50, DRM50, and LCSM50-DRM50). The experimental diets, which were isocaloric (metabolizable energy, 11.11 MJ/kg) and isonitrogenous (CP, 16.5%), had similar digestible amino acid profile. The feeding trial lasted 12 weeks. Results The daily egg mass was decreased in the LCSM100 and LCSM50-DRM50 groups (p0.05) and showed increased yolk color at the end of the trial (p0.05). Conclusion Together, our results suggest that the LCSM100 or DRM100 diets may produce the adverse effects on laying performance and egg quality after feeding for 8 more weeks. The 100.0 g/kg LCSM diet or the148.7 g/kg DRM diet has no adverse effects on laying performance and egg quality. PMID:27608634

  16. Crystallization and evaluation of hen egg-white lysozyme crystals for protein pH titration in the crystalline state.

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    Iwai, Wakari; Yagi, Daichi; Ishikawa, Takuya; Ohnishi, Yuki; Tanaka, Ichiro; Niimura, Nobuo

    2008-05-01

    To observe the ionized status of the amino acid residues in proteins at different pH (protein pH titration in the crystalline state) by neutron diffraction, hen egg-white lysozyme was crystallized over a wide pH range (2.5-8.0). Crystallization phase diagrams at pH 2.5, 6.0 and 7.5 were determined. At pH diagram, and at pH > 4.5 the border shifted to the right (higher precipitant concentration). The qualities of these crystals were characterized using the Wilson plot method. The qualities of all crystals at different pH were more or less equivalent (B-factor values within 25-40). It is expected that neutron diffraction analysis of these crystals of different pH provides equivalent data in quality for discussions of protein pH titration in the crystalline state of hen egg-white lysozyme.

  17. Detection of transgenic and endogenous plant DNA fragments and proteins in the digesta, blood, tissues, and eggs of laying hens fed with phytase transgenic corn.

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    Qiugang Ma

    Full Text Available The trials were conducted to assess the effects of long-term feeding with phytase transgenic corn (PTC to hens on laying performance and egg quality, and investigate the fate of transgenic DNA and protein in digesta, blood, tissues, and eggs. Fifty-week old laying hens (n = 144 were fed with a diet containing 62.4% PTC or non-transgenic isogenic control corn (CC for 16 weeks. We observed that feeding PTC to laying hens had no adverse effect on laying performance or egg quality (P>0.05 except on yolk color (P<0.05. Transgenic phyA2 gene and protein were rapidly degraded in the digestive tract and were not detected in blood, heart, liver, spleen, kidney, breast muscle, and eggs of laying hens fed with diet containing PTC. It was concluded that performance of hens fed diets containing PTC, as measured by egg production and egg quality, was similar to that of hens fed diets formulated with CC. There was no evidence of phyA2 gene or protein translocation to the blood, tissues, and eggs of laying hens.

  18. Detection of transgenic and endogenous plant DNA fragments and proteins in the digesta, blood, tissues, and eggs of laying hens fed with phytase transgenic corn.

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    Ma, Qiugang; Gao, Chunqi; Zhang, Jianyun; Zhao, Lihong; Hao, Wenbo; Ji, Cheng

    2013-01-01

    The trials were conducted to assess the effects of long-term feeding with phytase transgenic corn (PTC) to hens on laying performance and egg quality, and investigate the fate of transgenic DNA and protein in digesta, blood, tissues, and eggs. Fifty-week old laying hens (n = 144) were fed with a diet containing 62.4% PTC or non-transgenic isogenic control corn (CC) for 16 weeks. We observed that feeding PTC to laying hens had no adverse effect on laying performance or egg quality (P>0.05) except on yolk color (PTransgenic phyA2 gene and protein were rapidly degraded in the digestive tract and were not detected in blood, heart, liver, spleen, kidney, breast muscle, and eggs of laying hens fed with diet containing PTC. It was concluded that performance of hens fed diets containing PTC, as measured by egg production and egg quality, was similar to that of hens fed diets formulated with CC. There was no evidence of phyA2 gene or protein translocation to the blood, tissues, and eggs of laying hens.

  19. Influence of prelay treatment and dietary protein level on the reproductive performance of White Leghorn hens.

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    Summers, J D

    1993-09-01

    Two experiments were undertaken to study the influence of prelay diet treatment on subsequent laying performance. Feeding either a conventional laying or growing diet or diets containing essentially only wheat bran from 18 to 21 wk resulted in little grower diet carryover effect beyond 24 wk of age, although the wheat bran diets resulted in a marked drop in body weight of the pullets during the prelay treatment. Similar performance was noted for pullets in a second experiment in which prelay treatments consisted of feeding just corn or wheat bran from 18 to 20 wk of age. In interpreting the results of the present study, it is important to consider the fact that "mature pullet weights" were obtained before the prelay diet treatments were employed. Where prelay diet treatments have had significant effects on laying house performance, in most cases, immature or underweight pullets were involved. Feeding hens low-protein diets (13 versus 17%) from 20 to 44 wk of age resulted in similar egg production; however, egg weight and thus egg mass were slightly reduced with the lower protein diet. There was no laying by growing treatment interaction. The importance of good pullet weight at the start of the production cycle and the subsequent performance of such pullets fed low-protein diets is discussed.

  20. Reproductive performance and oviductal expression of avidin and avidin-related protein-2 in young and old broiler breeder hens orally exposed to supplementary biotin.

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    Daryabari, H; Akhlaghi, A; Zamiri, M J; Mianji, G Rahimi; Pirsaraei, Z Ansari; Deldar, H; Eghbalian, A N

    2014-09-01

    Published data on the probable involvement of avidin and avidin-related protein-2 (AVR2) in sustaining sperm viability in sperm storage tubules in 38-wk-old turkeys, and the high affinity of avidin or its analogs to biotin suggest that supplementary biotin may increase oviductal avidin and AVR2 expression, thereby attenuating the adverse effect of aging on hen reproductive performance. Broiler breeder hens (n = 120) were randomly assigned to receive 0 (T0), 0.30 (T1), or 0.45 (T2) mg of biotin/L of drinking water from 30 to 33 (young) and 53 to 56 (old) wk of age, and artificially inseminated to determine their reproductive performance. At the end of each period of biotin administration, 8 hens from each treatment group were killed for RNA extraction from the uterovaginal junction. Egg production was lower in the old hens (44%) compared with the young ones (82%), and biotin supplementation increased egg production only in the latter. Administering supplementary biotin to young hens increased their oviductal expression of AVR2, which was much higher in the old hens (1.0 and 4.6 for young and old groups, respectively). Fertility rate was not different between young and old hens, and was increased (4.4%) at the higher level of biotin supplementation. Hatchability and hatchling quality were not affected by biotin supplementation. Embryonic mortality between 17 to 21 d of incubation was higher in young (5.2%) compared with old (1.4%) birds. Egg fertility rate showed a moderate correlation (P biotin supplementation on AVR2 expression, and the relationship between biotin administration and oviductal expression of avidin and AVR2 was dependent on the hen's age, being higher in the young hens.

  1. Expression of Leukocyte Inhibitory Immunoglobulin-like Transcript 3 Receptors by Ovarian Tumors in Laying Hen Model of Spontaneous Ovarian Cancer.

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    Khan, Mohammad Faisal; Bahr, Janice M; Yellapa, Aparna; Bitterman, Pincas; Abramowicz, Jacques S; Edassery, Seby L; Basu, Sanjib; Rotmensch, Jacob; Barua, Animesh

    2012-04-01

    Attempts to enhance a patient's immune response and ameliorate the poor prognosis of ovarian cancer (OVCA) have largely been unsuccessful owing to the suppressive tumor microenvironment. Leukocyte immunoglobulin-like transcript 3 (ILT3) inhibitory receptors have been implicated in immunosuppression in several malignancies. The expression and role of ILT3 in the progression of ovarian tumors are unknown. This study examined the expression and association of ILT3 in ovarian tumors in laying hens, a spontaneous preclinical model of human OVCA. White Leghorn laying hens were selected by transvaginal ultrasound scanning. Serum and normal ovaries or ovarian tumors were collected. The presence of tumors and the expression of ILT3 were examined by routine histology, immunohistochemistry, Western blot analysis, and reverse transcription-polymerase chain reaction. In addition to stromal immune cell-like cells, the epithelium of the ovarian tumors also expressed ILT3 with significantly high intensity than normal ovaries. Among different subtypes of ovarian carcinomas, serous OVCA showed the highest ILT3 staining intensity, whereas endometrioid OVCA had the lowest intensity. Similar to humans, an immunoreactive protein band of approximately 55 kDa for ILT3 was detected in the ovarian tumors in hens. The patterns of ILT3 protein and messenger RNA expression by ovarian tumors in different subtypes and stages were similar to those of immunohistochemical staining. The results of this study suggest that laying hens may be useful to generate information on ILT3-associated immunosuppression in OVCA. This animal model also offers the opportunity to develop and test anti-ILT3 immunotherapy to enhance antitumor immunity against OVCA in humans.

  2. Investigation on the effects of dietary protein reduction with constant ratio of digestible sulfur amino acids and threonine to lysine on performance, egg quality and protein retention in two strains of laying hens

    Directory of Open Access Journals (Sweden)

    Farhad Foroudi

    2013-01-01

    Full Text Available An experiment was conducted to determine the possibility of using various levels of crude protein (CP by providing laying hens with constant levels of digestible sulfur amino acid, threonine and lysine to improve performance and egg quality. The experiment was conducted as a completely randomized block design in a factorial arrangement (4 × 2 with 8 replicates of 10 hens in each. Factors included 4 levels of CP (18.5%, 17.5%, 16.5% and 15.5% and 2 strains (LSL and Hy-Line W-36 of laying hens. Hens were fed experimental diets from 25 to 33 weeks of age. Production performance was measured for eight weeks and egg quality characteristics were determined at 29 and 33 weeks of age. Protein reduction decreased egg weight, egg mass and hen body weight linearly (P≤0.01. Egg production was not affected by protein reduction but feed efficiency, and average daily feed intake increased significantly (P≤0.01. Lohmann Selected Leghorn laying hens showed significantly higher egg production, egg weight, egg mass, weight gain, feed efficiency and feed intake compared to the W-36 laying hens (P≤0.01. Shell thickness increased linearly as protein levels decreased (P≤0.05. There were significant differences between two strains on the egg quality characteristics (P≤0.01. Significant (P≤0.05 CP × strain interactions were observed for hen weight, albumen height, Haugh units, yolk and shell percentage. Based on the results of this experiment, a reduction in dietary protein level (from 18.5% to 15.5%, without any alteration in digestible TSAA and Thr: Lys ratio, led to inferior egg mass and feed conversion ratio during the peak production period.

  3. Recombinant proteins from Gallibacterium anatis induces partial protection against heterologous challenge in egg-laying hens

    DEFF Research Database (Denmark)

    Pors, Susanne Elisabeth; Skjerning, Ragnhild Bager; Flachs, Esben M.;

    2016-01-01

    are urgently required. The aim of the present study was to evaluate the cross-protective capacity of three recombinant proteins recently identified as potential vaccine candidates; GtxA-N, GtxA-C, and FlfA, in an in vivo challenge model. Nine groups of birds were immunized twice with each protein, respectively...

  4. Ability of non-linear mixed models to predict growth in laying hens

    Directory of Open Access Journals (Sweden)

    Luis Fernando Galeano-Vasco

    2014-11-01

    Full Text Available In this study, the Von Bertalanffy, Richards, Gompertz, Brody, and Logistics non-linear mixed regression models were compared for their ability to estimate the growth curve in commercial laying hens. Data were obtained from 100 Lohmann LSL layers. The animals were identified and then weighed weekly from day 20 after hatch until they were 553 days of age. All the nonlinear models used were transformed into mixed models by the inclusion of random parameters. Accuracy of the models was determined by the Akaike and Bayesian information criteria (AIC and BIC, respectively, and the correlation values. According to AIC, BIC, and correlation values, the best fit for modeling the growth curve of the birds was obtained with Gompertz, followed by Richards, and then by Von Bertalanffy models. The Brody and Logistic models did not fit the data. The Gompertz nonlinear mixed model showed the best goodness of fit for the data set, and is considered the model of choice to describe and predict the growth curve of Lohmann LSL commercial layers at the production system of University of Antioquia.

  5. [Immunologic analysis of milk, hen egg, and soybean proteins in butter and margarine, and clinical assessment for availability of hypoallergenic margarine (HAM)].

    Science.gov (United States)

    Yokota, S; Takahashi, Y; Aihara, Y; Kurihara, K; Suguro, H; Matsuyama, S

    1996-12-01

    To determine the allergenic proteins in commercially available butter and margarine, protein fractions were extracted and immunologically analyzed against milk, hen egg, and soybean antigens. Butter and 10 kinds of margarine were proved to contain these proteins in various concentrations by ELISA and immunoblotting methods by use of the rabbit antisera developed against each food proteins. However, hypoallergenic margarine was found to contain no such proteins at all. Using sera obtained from atopic dermatitis patients, previously detected high levels of IgE antibodies to milk, hen egg, or soybeans, the extracted protein fraction from butter and margarine was analyzed whether these proteins react with IgG antibodies in patients' sera. The sera with high levels of specific IgE recognized protein antigens in these extracts except those from hypoallergenic margarine, suggesting that proteins in butter and margarine may become allergenic for the patients sensitive to the proteins, and that hypoallergenic margarine will be a reasonable alternative for the allergic patients to milk, hen egg, or soybeans.

  6. Effect of dietary energy and protein on the performance, egg quality, bone mineral density, blood properties and yolk fatty acid composition of organic laying hens

    Directory of Open Access Journals (Sweden)

    Md. Rakibul Hassan

    2013-02-01

    Full Text Available An experiment was conducted to evaluate the effect of dietary metabolizable energy (ME and crude protein (CP on the performance, egg quality, blood properties, bone characteristics and yolk fatty acid composition of organic laying hens. At 23 weeks, a total of 600 Brown nick laying hens were randomly distributed into 24 outdoor pens (4 replicate pens/treatment; 25 birds/pen and were given (2750, 2775 and 2800 kcal of ME/kg and CP (16 and 17% resulting in a 3×2 factorial arrangement of organic dietary treatments. The experiment lasted 23 weeks. The performance of laying hens were not affected by the dietary treatment while the egg weight was increased with energy and CP levels in the diet (P<0.05. Serum total protein was not affected by dietary energy and protein level. Total cholesterol and triglyceride tend to reduce with the increasing amount of CP in the diet. Thereafter, bone and egg quality characteristics were numerically increased in dietary 2775 kcal of ME/kg and 16% CP treatment. On the other hand, docosahexanoic acid content in egg yolk was higher (P<0.01 in 2750 kcal of ME/kg and 17% CP treatment. As a result, the performance, blood and fatty acid composition were maximized in 2750 kcal of ME/kg and 16% CP treatment. Thus, dietary 2750-2775 kcal of ME/kg and 16% CP may enhance performance, blood and fatty acid composition of organic laying hens.

  7. High-pressure protein crystallography of hen egg-white lysozyme

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Hiroyuki; Nagae, Takayuki [Nagoya University, Chikusa, Nagoya, Aichi 464-8603 (Japan); Watanabe, Nobuhisa, E-mail: nobuhisa@nagoya-u.jp [Nagoya University, Chikusa, Nagoya, Aichi 464-8603 (Japan); Nagoya University, Chikusa, Nagoya, Aichi 464-8603 (Japan)

    2015-04-01

    The crystal structure of hen egg-white lysozyme (HEWL) was analyzed under pressures of up to 950 MPa. The high pressure modified the conformation of the molecule and induced a novel phase transition in the tetragonal crystal of HEWL. Crystal structures of hen egg-white lysozyme (HEWL) determined under pressures ranging from ambient pressure to 950 MPa are presented. From 0.1 to 710 MPa, the molecular and internal cavity volumes are monotonically compressed. However, from 710 to 890 MPa the internal cavity volume remains almost constant. Moreover, as the pressure increases to 950 MPa, the tetragonal crystal of HEWL undergoes a phase transition from P4{sub 3}2{sub 1}2 to P4{sub 3}. Under high pressure, the crystal structure of the enzyme undergoes several local and global changes accompanied by changes in hydration structure. For example, water molecules penetrate into an internal cavity neighbouring the active site and induce an alternate conformation of one of the catalytic residues, Glu35. These phenomena have not been detected by conventional X-ray crystal structure analysis and might play an important role in the catalytic activity of HEWL.

  8. Modelling hen harrier dynamics to inform human-wildlife conflict resolution: a spatially-realistic, individual-based approach.

    Directory of Open Access Journals (Sweden)

    Johannes P M Heinonen

    Full Text Available Individual-based models have gained popularity in ecology, and enable simultaneous incorporation of spatial explicitness and population dynamic processes to understand spatio-temporal patterns of populations. We introduce an individual-based model for understanding and predicting spatial hen harrier (Circus cyaneus population dynamics in Great Britain. The model uses a landscape with habitat, prey and game management indices. The hen harrier population was initialised according to empirical census estimates for 1988/89 and simulated until 2030, and predictions for 1998, 2004 and 2010 were compared to empirical census estimates for respective years. The model produced a good qualitative match to overall trends between 1989 and 2010. Parameter explorations revealed relatively high elasticity in particular to demographic parameters such as juvenile male mortality. This highlights the need for robust parameter estimates from empirical research. There are clearly challenges for replication of real-world population trends, but this model provides a useful tool for increasing understanding of drivers of hen harrier dynamics and focusing research efforts in order to inform conflict management decisions.

  9. Protein turnover in the breast muscle of broiler chicks and studies addressing chlorine dioxide sanitation of hatching eggs, poultry leg problems and wheat middling diets for laying hens

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, P.H.

    1988-01-01

    Developmental changes occurred in breast muscle Ks measured by {sup 14}C-tyrosine incorporation at 10, 16, 22 and 34 days of age. Protein synthesis rates decreased as the birds matures: 30 to 11.2%/d between 10 and 34 days of age. In a second study birds fed diets low in lysine or protein-energy had reduced fractional rates of protein synthesis and free tyrosine, branched chain and large neutral amino acid concentrations as compared to control birds the same body weight. Artificial weight loading and reduced dietary protein levels were used to study the effects of body weight on the severity of leg deformities in chicks and poults. Experiments investigating the practicality of wheat middlings as an alternate feedstuff for laying hens suggested that high levels in the diet will reduce egg production, feed conversion, hen livability and egg yolk color. Lastly, chlorine dioxide foam and dipping solutions were compared with formaldehyde fumigation for sanitizing hatching eggs.

  10. Effect of different levels of methionine, protein and tallow on the productive performance and egg quality of laying hens in the late-phase production

    Directory of Open Access Journals (Sweden)

    H Nassiri Moghaddam

    2012-06-01

    Full Text Available An experiment was conducted to determine the effects of different levels of methionine, protein and tallow on productive performance and egg quality of laying hens in the late phase of production. A completely randomized design with a 3×2×2 factorial arrangement, with three levels (0.34, 0.31, and 0.27% of methionine (MET, two levels (12.8 and 14.7% of protein (PRO and two levels (1 and 3% of tallow (TAL with constant level of linoleic acid (1.55 ± 0.02%, was used. A number of 144 Hi-Line W-36 layers from 70 to 76 wk of age was randomly distributed into 12 treatment groups with 4 replicates of 3 hens each. Egg production and egg weight were daily recorded and feed intake and egg quality traits were recorded every 2 wk. There was a significant interaction between PRO levels and TAL for egg weight. Low levels of TAL and PRO decreased egg weight throughout the experiment. High levels of MET and TAL with concomitant reduced PRO, increased eggshell thickness, and a significant interaction between levels of MET, PRO and TAL was observed during the experiment (70 to 76 wk. Low level of protein (12.8% significantly decreased albumen weight in the third 2-wk period. Yolk color increased when hens were fed low levels of PRO and TAL. Results of this experiment indicated that the simultaneous reduction of dietary PRO and MET in diets of Hi-Line W-36 laying hens in the late phase of production, reduced egg weight (P<0.05. Productive performance and egg quality were not affected by 12 and 20% reduction of PRO and MET, respectively. It seems that decreasing the levels of MET and PRO to lower than the recommended values can decrease egg weight without negative effects on productive performance and egg quality of laying hens in the late phase of production.

  11. Low protein and high-energy diet: a possible natural cause of fatty liver hemorrhagic syndrome in caged White Leghorn laying hens.

    Science.gov (United States)

    Rozenboim, I; Mahato, J; Cohen, N A; Tirosh, O

    2016-03-01

    Fatty liver hemorrhagic syndrome (FLHS) is a metabolic condition of chicken and other birds caused by diverse nutritional, hormonal, environmental, and metabolic factors. Here we studied the effect of different diet composition on the induction of FLHS in single comb White Leghorn (WL) Hy-line laying hens. Seventy six (76) young WL (26 wks old) laying hens and 69 old hens (84 wks old) of the same breed were each divided into 4 treatment groups and provided 4 different diet treatments. The diet treatments included: control (C), 17.5% CP, 3.5% fat (F); normal protein, high fat (HF), 17.5% CP, 7% F; low protein, normal fat (LP), 13% CP, 3.5% F; and low protein, high fat (LPHF), 13% CP, 6.5% F. The diets containing high fat also had a higher ME of 3,000 kcal/kg of feed while the other 2 diets with normal fat had a regular lower amount of ME (2750 kcal/kg). Hen-day egg production (HDEP), ADFI, BW, egg weight, plasma enzymes indicating liver damage (alkaline phosphatase [ALP], aspartate aminotransferase [AST], gamma-glutamyl transferase [GGT]), liver and abdominal fat weight, liver color score (LCS), liver hemorrhagic score (LHS), liver fat content (LFC), liver histological examination, lipid peroxidation product in the liver, and genes indicating liver inflammation were evaluated. HDEP, ADFI, BW, and egg weight were significantly decreased in the LPHF diet group, while egg weight was also decreased in the LP diet group. In the young hens (LPHF group), ALP was found significantly higher at 30 d of diet treatment and was numerically higher throughout the experiment, while AST was significantly higher at 105 d of treatment. LCS, LHS, and LFC were significantly higher in young hens on the LPHF diet treatment. A liver histological examination shows more lipid vacuolization in the LPHF treatment diet. HF or LP alone had no significant effect on LFC, LHS, or LCS. We suggest that LP in the diet with higher ME from fat can be a possible natural cause for predisposing laying hens

  12. Individual and combined effects of crude protein, methionine, and probiotic levels on laying hen productive performance and nitrogen pollution in the manure.

    Science.gov (United States)

    Alagawany, Mahmoud; Abd El-Hack, Mohamed E; Arif, Muhammad; Ashour, Elwy A

    2016-11-01

    The present study aimed to investigate the effect of the dietary levels of protein, methionine (Met), as well as probiotic on productive performance, feed utilization, and environmental pollution by N in Lohmann Brown laying hens. A total number of 160 Lohmann Brown laying hens at 20 weeks of age were randomly divided into 8 treatment groups using a 2 × 2 × 2 factorial design experiment. The experiment involved two levels of crude protein (16 and 18 %), two levels of Met (0.45 and 0.50 %), and two concentrations of probiotic (0 or 1 g/kg diet, with a concentration of 10(10) CFU/g of Lactobacillus acidophilus) within 20-42 weeks of age. Results revealed that egg production parameters were significantly (P hens fed diets of 18 % CP comparing with that of 16 % protein within the period from 26 to 30 weeks of age. Protein utilization and feed efficiency values were enhanced with 0.67 and 0.72 % Met during the period of 26-30 weeks of the age. For the N pollution, results showed that increasing crude protein in the diet from 16 to 18 % caused significant (P laying hens through the whole experimental period. Ecologically, reducing the level of crude protein in layer diets to be 16 % along with the supplementation of Met can play an important role in minimizing the pollution with N from poultry excretion.

  13. Response of laying hens to feeding low-protein amino acid-supplemented diets under high ambient temperature: performance, egg quality, leukocyte profile, blood lipids, and excreta pH

    Science.gov (United States)

    Torki, Mehran; Mohebbifar, Ahmad; Ghasemi, Hossein Ali; Zardast, Afshin

    2015-05-01

    An experiment was conducted to determine whether, by using a low-protein amino acid-supplemented diet, the health status, stress response, and excreta quality could be improved without affecting the productive performance of heat-stressed laying hens. The requirements for egg production, egg mass, and feed conversion ratio were also estimated using second-order equations and broken-line regression. A total of 150 Lohmann Selected Leghorn (LSL-Lite) hens were divided randomly into five groups of 30 with five replicates of six hens. The hens were raised for an 8-week period (52 to 60 weeks) in wire cages situated in high ambient temperature in an open-sided housing system. The five experimental diets (ME; 2,720 kcal/kg) varied according to five crude protein (CP) levels: normal-CP diet (control, 16.5 % CP) and low-CP diets containing 15.0, 13.5, 12.0, or 10.5 % CP. All experimental diets were supplemented with crystalline amino acids at the levels sufficient to meet their requirements. The results showed that under high temperature conditions, all productive performance and egg quality parameters in the birds fed with 15.0, 13.5, and 12.0 % CP diets were similar to those of birds fed with control diet (16.5 % CP), whereas feeding 10.5 % CP diet significantly decreased egg production and egg mass. Estimations of requirements were of 13.93 and 12.77 % CP for egg production, 14.62 and 13.22 % CP for egg mass, and 12.93 and 12.26 % CP for feed conversion ratio using quadratic and broken-line models, respectively. Egg yolk color index, blood triglyceride level, and excreta acidity were also significantly higher in birds fed with 12.0 and 10.5 % CP diets compared with those of control birds. The heterophil to lymphocyte ratio, as a stress indicator, was significantly decreased by 15.0, 13.5, and 12 % CP diets. On the basis of our findings, reducing dietary CP from 16.5 to 12.0 % and supplementing the diets with the essential amino acids showed merit for improving the

  14. Response of laying hens to feeding low-protein amino acid-supplemented diets under high ambient temperature: performance, egg quality, leukocyte profile, blood lipids, and excreta pH.

    Science.gov (United States)

    Torki, Mehran; Mohebbifar, Ahmad; Ghasemi, Hossein Ali; Zardast, Afshin

    2015-05-01

    An experiment was conducted to determine whether, by using a low-protein amino acid-supplemented diet, the health status, stress response, and excreta quality could be improved without affecting the productive performance of heat-stressed laying hens. The requirements for egg production, egg mass, and feed conversion ratio were also estimated using second-order equations and broken-line regression. A total of 150 Lohmann Selected Leghorn (LSL-Lite) hens were divided randomly into five groups of 30 with five replicates of six hens. The hens were raised for an 8-week period (52 to 60 weeks) in wire cages situated in high ambient temperature in an open-sided housing system. The five experimental diets (ME; 2,720 kcal/kg) varied according to five crude protein (CP) levels: normal-CP diet (control, 16.5 % CP) and low-CP diets containing 15.0, 13.5, 12.0, or 10.5 % CP. All experimental diets were supplemented with crystalline amino acids at the levels sufficient to meet their requirements. The results showed that under high temperature conditions, all productive performance and egg quality parameters in the birds fed with 15.0, 13.5, and 12.0 % CP diets were similar to those of birds fed with control diet (16.5 % CP), whereas feeding 10.5 % CP diet significantly decreased egg production and egg mass. Estimations of requirements were of 13.93 and 12.77 % CP for egg production, 14.62 and 13.22 % CP for egg mass, and 12.93 and 12.26 % CP for feed conversion ratio using quadratic and broken-line models, respectively. Egg yolk color index, blood triglyceride level, and excreta acidity were also significantly higher in birds fed with 12.0 and 10.5 % CP diets compared with those of control birds. The heterophil to lymphocyte ratio, as a stress indicator, was significantly decreased by 15.0, 13.5, and 12 % CP diets. On the basis of our findings, reducing dietary CP from 16.5 to 12.0 % and supplementing the diets with the essential amino acids showed merit for improving the

  15. Utilisation of Giant African snail (Achatina fulica meal as protein source for laying hens

    Directory of Open Access Journals (Sweden)

    Siaka Seriba Diarra

    2015-05-01

    Full Text Available A 12-week experiment was carried out to investigate the effects of substituting Giant African snail meal for fish meal in laying hens diet. Four diets were formulated to contain snail meal as replacement for fish meal at 0 (control, 33, 67 and 100 %. A total of 120 Shaver Brown pullets aged 18 weeks were allocated to the dietary treatments in a randomised design. Each treatment consisted of three replicates and ten birds per replicate. Feed intake increased only for the 33% treatment as compared to the 67% replacement diet but did not differ from the other treatments. There were no significant treatment effects on egg performance parameters observed (egg production, egg weight, total egg mass, feed conversion ratio and percent shell. The overall feed cost of egg production reduced on the snail mealbased diets. The organoleptic evaluation of boiled eggs revealed no difference between the treatments. Based on these results it was concluded that total replacement of fish meal with cooked snail meat meal does not compromise laying performance or egg quality. The substitution is beneficial in terms of production cost reduction and the reduction of snails will have a beneficial impact especially where these snails are a serious agricultural pest. The manual collection and processing of snails can also become a source of rural income.

  16. 三磷甲苯磷酸酯暴露对鸡脊髓神经中髓鞘碱性蛋白表达的影响%Difference of myelin basic protein expression the hen spinal cord tisse of tri - ortho - cresyl phosphate - treated hens

    Institute of Scientific and Technical Information of China (English)

    韩雪榕; 朴丰源

    2011-01-01

    [Objective] To investigate the special difference of myelin basic protein in the hen spinal cord tissue after or-ganophosphorus ester - induced delayed neuropathy. [ Methods ] Forty - eight Roman hens were randomly divided into three groups; treated - group (1000 mg/kg tri - ortho - cresyl phosphate,TOCP); intervented - group (40 mg/kg phenyl-methanesulfonyl fluoride (PMSF) before treated - group; control group (tap water), every group have 16 hens. Eight hens in every groups were sacrificed on the d5 ,d20 separately, which separate spinal cord tissue at low temperatures and extract total protein. With solid phase PH gradient SDS - PAGE two - dimensional electrophoresis and mass spectrometry ,we screen differently expressed proteins related to demyelination. [ Results] Comparing with control group, the difference of myelin basic protein(MBP) has no significance on the d5, while on the d20,the expression rates treated - group、intervented -group were 0.3667 and 0.7601 receptively(ratio have no significace beween 0.5 and 2). [ Conclusion] The expression of MBP is downregulated in the hen spinal cord tissue after organophosphorus ester - induced delay neuropathy, which may relate to demyelination of OPIDN model.%[目的]探讨有机磷化合物(organophosphorvs compounds,OPs)引起迟发型神经毒性(organophosphorus esterinduced delayed neuropathy,OPIDN)后鸡的神经组织中髓鞘碱性蛋白(myelin basic protein,MBP)表达的变化.[方法]罗曼鹤母鸡48只,随机分成染毒组:给予1000 mg/kg三磷甲苯磷酸酯(tri - ortho - cresyl phosphate,TOCP)、苯甲基磺酰氟(phenylmethanesul fonyl fluoride,PMSF)前干预组:在染毒组之前给予40 mg/kg PMSF和对照组(生理盐水),每组16只.染毒第5天和第20天,每组分别处死8只动物,低温环境下分离腰髓,提取总蛋白.用双向电泳和质谱分析技术,筛选可能与脱髓鞘相关的差异表达蛋白.[结果]经双向电泳和质谱分析表明,在染毒第5

  17. Uterine fluid proteins and egg quality characteristics for 2 commercial and 2 heritage laying hen lines in response to manipulation of dietary calcium and vitamin D3.

    Science.gov (United States)

    Kaur, Ravinder; Rathgeber, Bruce M; Thompson, Kristen L; Macisaac, Janice

    2013-09-01

    The aim of this study was to evaluate the quality of eggs from 2 selected commercial strains of laying hens and 2 unselected lines of chickens fed diets with different combinations of Ca and vitamin D and relate it to the profile of uterine proteins and ultrastructure of the shell. A group of 4 chickens was housed in each of 24 cages. The group consisted of one representative from each of the following breeds: Lohmann LSL- Lite, Lohmann Classic-Brown, Fayoumi, and Light Sussex. Six dietary combinations of Ca and vitamin D(3) (3.35%, 2,500 IU; 4.10%, 2,500 IU (control); 4.85%, 2,500 IU; 3.35%, 200 IU; 4.10%, 200 IU; and 4.85%, 200 IU) were randomly assigned to 4 replicate cages for 2 treatment periods (26-29 and 56-59 wk of age). Data were analyzed as a split-plot design with cage as the main plot and hen as the subplot. Egg quality traits were different (P hens age.

  18. Influence of Dermanyssus gallinae (poultry red mite) invasion on the plasma levels of corticosterone, catecholamines and proteins in layer hens.

    Science.gov (United States)

    Kowalski, A; Sokół, R

    2009-01-01

    The results of studies conducted in 2006 revealed that mass red mite (Dermanyssus gallinae) invasions cause somatic stress which may be responsible for the pathophysiological mechanism of decreased egg production, lower humoral immunity and higher mortality in layer hens. The aim of this study was to validate the above research results, to investigate whether in addition to somatic stress, red mite invasions cause psychogenic stress due to the activation of the sympatho-adrenomedullar system, and to determine the level of stress resulting from red mite infestations in comparison with a short, 1.5 h period of acute immobilisation stress. The study investigated 36 HY-Line Brown layer hens divided into three groups: a non-infested control group, an experimental group infested with red mites and a non-infested experimental group subjected to acute immobilisation stress for 1.5 h. Blood samples were taken from all hens for the determination of the levels of corticosterone, adrenaline, noradrenaline, albumin, and alpha-, beta- and gamma-globulins. The results validated the previous reports on the occurrence of somatic stress and on a significant decrease in y-globulin levels (p < or = 0.01) in the group of birds infested with red mites, in comparison with the control group. Adrenaline levels in infested hens were indicative of psychogenic stress. Based on a comparison of hormonal indicators in all hen groups, the level of somatic stress resulting from red mite infestation can be classified as moderate, while the level of psychogenic stress can be interpreted as high. A significant drop in y-globulin levels in the blood of birds infested with red mites also shows that the invasion induces chronic stress which lowers the humoral immunity of hens.

  19. 饲粮粗蛋白质水平对济宁百日蛋种鸡生产性能的影响%Effects of Dietary Crude Protein Levels on Performance of Jining Bairi Laying Hens

    Institute of Scientific and Technical Information of China (English)

    殷若新; 曹丙健; 胡希怡; 丁祥文; 苏鹏程; 宋志刚

    2016-01-01

    本试验通过研究饲粮粗蛋白质水平对济宁百日蛋种鸡生产性能的影响,建立蛋白质需要量析因模型,确定济宁百日蛋种鸡饲粮粗蛋白质的需要量。采用单因素完全随机试验设计,饲粮粗蛋白质水平分别为13%、14%、15%、16%、17%,其他营养指标保持一致。选取40周龄、体重接近的健康济宁百日蛋种鸡525只,随机分为5组,每组5个重复,每个重复21只。预试期7 d,试验期56 d。结果表明:1)饲粮粗蛋白质水平对济宁百日蛋种鸡平均日粗蛋白质摄入量(ADCPI)有极显著的影响(P<0.01),随着饲粮粗蛋白质水平的升高,ADCPI 显著升高(P<0.05)。2)饲粮粗蛋白质水平对济宁百日蛋种鸡41~48周龄的产蛋数、产蛋率、平均蛋重、平均日产蛋量( ADEM)均有显著影响( P<0.05),对料蛋比有极显著影响( P<0.01);高粗蛋白质水平组(16%、17%)的产蛋数、产蛋率、ADEM均高于低粗蛋白质水平组(13%、14%、15%)。在一定的饲粮粗蛋白质水平(13%~16%)范围内,蛋重有随着饲粮粗蛋白质水平的升高而升高的趋势。3)以ADCPI为因变量,以平均日增重( ADG)、ADEM和代谢体重( BW0.75)为自变量,拟合济宁百日蛋种鸡粗蛋白质需要析因模型为:ADCPI=0.2680 ADG+0.2711 ADEM+3.2993 BW0.75( R2=0.9934)。满足济宁百日蛋种鸡41~48周龄时最佳生产性能的适宜饲粮粗蛋白质水平为15.49%。%This experiment was conducted to study the effects of dietary crude protein levels on performance of Jining Bairi laying hens, and to establish factorial model of crude protein requirements, and to define the crude protein requirements of Jining Bairi laying hens. A single⁃factor completely randomized experiment design was applied. The crude protein levels of the experimental diets were 13%, 14%, 15%, 16% and 17

  20. Recombinant proteins from Gallibacterium anatis induces partial protection against heterologous challenge in egg-laying hens

    DEFF Research Database (Denmark)

    Pors, Susanne Elisabeth; Skjerning, Ragnhild Bager; Flachs, Esben M.

    2016-01-01

    after challenge. All birds were euthanized and subjected to a post mortem procedure including scoring of lesions and sampling for bacterial growth. Moreover, ELISA assays were used to quantify antigen-specific IgG titers in serum. The results showed that all three proteins induced protection against...

  1. The effect of chronic ammonia exposure on acute phase proteins, immunoglobulin and cytokines in laying hens

    Science.gov (United States)

    Ammonia is a potential health hazard to both humans and animals, causing systemic low-grade inflammation based on its levels and durations. The objective of this study was to examine the effect of 45 weeks of exposure to 30 ppm NH3 on the concentrations of acute phase proteins, immunoglobulins and c...

  2. Reduction of Salmonella Enteritidis in the spleens of hens by bacterins that vary in fimbrial protein SefD

    Science.gov (United States)

    Gene sefD is part of operon sefABCD, and it is required for production of the SEF14 fimbria by Salmonella Enteritidis. We compared strains that varied in SefD content for their ability to reduce recovery of Salmonella Enteritidis from the spleens of hens infected by parenteral challenge. The two bac...

  3. Small intestine development of laying hens fed different fiber sources diets and crude protein levels

    Directory of Open Access Journals (Sweden)

    MFFM Praes

    2011-09-01

    Full Text Available The objective of the presente study was to evaluate the effects on different dietary fiber sources and crude protein levels on the intestinal morphometry of commercial layers. Isa Brown® layers with 48 weeks of age were distributed in a completely randomized experimental design with a 3 x 2 + 1 factorial arrangement, resulting in seven treatments with seven replicates of eight birds each. At the end of the fourth experimental period (28 days each, birds were 64 weeks of age and were randomly chosen (two birds per replicate, totaling 14 birds per treatment, weighed and sacrificed by neck dislocation. Their intestine was dissected and the duodenum, jejunum and ileum were collected for subsequent analysis of intestinal morphometry. Treatments consisted of diets containing three different fiber sources (cottonseed hulls, soybean hulls or rice husks and two crude protein levels (12% or 16%. Soybean hulls and 16% crude protein level promoted, in general, an increase in villus height and crypt depth in the three intestinal segments. In the duodenum, the control diet resulted in higher villus height and crypt depth relative to the diets containing fiber. In the jejunum, higher crypt depth values. In the ileum, dietary fiber increased villus height as compared to the control diet.

  4. Interleukin 16- (IL-16- Targeted Ultrasound Imaging Agent Improves Detection of Ovarian Tumors in Laying Hens, a Preclinical Model of Spontaneous Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Animesh Barua

    2015-01-01

    Full Text Available Limited resolution of transvaginal ultrasound (TVUS scanning is a significant barrier to early detection of ovarian cancer (OVCA. Contrast agents have been suggested to improve the resolution of TVUS scanning. Emerging evidence suggests that expression of interleukin 16 (IL-16 by the tumor epithelium and microvessels increases in association with OVCA development and offers a potential target for early OVCA detection. The goal of this study was to examine the feasibility of IL-16-targeted contrast agents in enhancing the intensity of ultrasound imaging from ovarian tumors in hens, a model of spontaneous OVCA. Contrast agents were developed by conjugating biotinylated anti-IL-16 antibodies with streptavidin coated microbubbles. Enhancement of ultrasound signal intensity was determined before and after injection of contrast agents. Following scanning, ovarian tissues were processed for the detection of IL-16 expressing cells and microvessels. Compared with precontrast, contrast imaging enhanced ultrasound signal intensity significantly in OVCA hens at early (P<0.05 and late stages (P<0.001. Higher intensities of ultrasound signals in OVCA hens were associated with increased frequencies of IL-16 expressing cells and microvessels. These results suggest that IL-16-targeted contrast agents improve the visualization of ovarian tumors. The laying hen may be a suitable model to test new imaging agents and develop targeted anti-OVCA therapeutics.

  5. Oral administration of supplementary biotin differentially influences the fertility rate and oviductal expression of avidin and avidin-related protein-2 in low- and high-fertility broiler line hens.

    Science.gov (United States)

    Daryabari, H; Akhlaghi, A; Zamiri, M J; Pirsaraei, Z Ansari; Mianji, G Rahimi; Deldar, H; Eghbalian, A N

    2015-02-01

    Probable involvement of avidin and avidin-related protein-2 (AVR2) in sperm viability in the sperm storage tubules of turkeys has been suggested. The high affinity of biotin to avidin and its analogs is also well documented. The present study aimed to determine the effect of oral biotin on reproductive performance and oviductal mRNA expression of avidin and AVR2 in 2 broiler hen lines with different fertility rates. Low-fertility (line B) and high-fertility (line D) hens (n=144) were randomly allotted to receive 0 (T0), 0.30 (T1), or 0.45 (T2) mg/L biotin in drinking water from 30 through 33 wk of age. The reproductive performance of the hens was evaluated using artificial insemination. At the end of the treatment period, 24 hens per line were killed to assay the expression of avidin and AVR2 in the uterovaginal junction. Supplementary biotin increased egg production from 73.5% for T0 to 87.8% for T2. Hens administered with biotin in line B, but not in line D, showed an increase (8.4%) in fertility rate. Hatchability, chick quality, and overall embryonic mortality were not different among the experimental groups. Real-time PCR data showed that both avidin (P=0.0013) and AVR2 (Pavidin and AVR2 mRNA expression, although biotin did not affect these traits in line D hens. Control hens in line D had a dramatically higher AVR2 expression record (7.4-fold) compared with the control hens in line B. The correlation coefficients of fertility rate and avidin expression were 0.73 and 0.66 in lines B and D, respectively. However, the correlation of fertility and AVR2 (r=0.65) was significant for line D hens only. Overall, fertility rate and oviductal expression of avidin and AVR2 were dichotomously affected by oral biotin in low- and high-fertility line hens, where only low-fertility birds showed improvements in these attributes. © 2015 Poultry Science Association Inc.

  6. Sensory evaluation by gamma radiation effect on protein allergen of laying hen eggs

    Science.gov (United States)

    Harder, M. N. C.; Arthur, V.; Perina, V. C. S.; Silva, L. C. A. S.; Bortoleto, G. G.

    2012-08-01

    Although considered the most complete food and nutritionally shown to be part of a healthy diet, the egg is the source of many eating disorders, especially for infants. Irradiation has been used in studies not only as a means of microbiological control, but also on its structural action in the substances molecules and has been used to reduce the allergenic effects. The aim of this study was to evaluate the sensory effects of Co60 gamma radiation on proteins, enabling the acceptability of allergy food for genetically intolerant people. Eggs commercial fresh and freeze-dried and subjected to gamma irradiation by Co60 source at doses 0 (control), 10 kGy; 20 kGy and 30 kGy and rates of doses of 19.4 kGy/h and 31.8 kGy/h. Acceptability test was used by the hedonic scale, since it is necessary to know the "affective status" of consumers for the product, implying a preference, i.e. the most preferred samples are the most accepted and vice versa. The samples were presented as the habit of consumption (cooked) to a group of 41 adults panelists of both gender, aged from 21 to 40 years, and served under complete block design balanced with respect to the order of presentation. The evaluated attributes was flavor, appearance and overall acceptability. In general, for boiled eggs and freeze-dried, it was observed that the control sample was the most acceptable, followed by the sample irradiated with 10 kGy in both dose rates. In addition, panelists presented in testimony that they found interesting changes due to irradiation; also said they would not buy the product because of the marked change in appearance and smell, which at one point he ended up in disgust and detract from sales of the product, but they would buy irradiated with 10 kGy in both dose rate and dose of 20 kGy at a dose rate of 19.4 kGy/h.

  7. Tuberal hypothalamic expression of the glial intermediate filaments, glial fibrillary acidic protein and vimentin across the turkey hen (Meleagris gallopavo) reproductive cycle: Further evidence for a role of glial structural plasticity in seasonal reproduction.

    Science.gov (United States)

    Steinman, Michael Q; Valenzuela, Anthony E; Siopes, Thomas D; Millam, James R

    2013-11-01

    Glia regulate the hypothalamic-pituitary-gonadal (HPG) axis in birds and mammals. This is accomplished mechanically by ensheathing gonadotrophin-releasing hormone I (GnRH) nerve terminals thereby blocking access to the pituitary blood supply, or chemically in a paracrine manner. Such regulation requires appropriate spatial associations between glia and nerve terminals. Female turkeys (Meleagris gallopavo) use day length as a primary breeding cue. Long days activate the HPG-axis until the hen enters a photorefractory state when previously stimulatory day lengths no longer support HPG-axis activity. Hens must then be exposed to short days before reactivation of the reproductive axis occurs. As adult hens have discrete inactive reproductive states in addition to a fertile state, they are useful for examining the glial contribution to reproductive function. We immunostained tuberal hypothalami from short and long-day photosensitive hens, plus long-day photorefractory hens to examine expression of two intermediate filaments that affect glial morphology: glial fibrillary acidic protein (GFAP) and vimentin. GFAP expression was drastically reduced in the central median eminence of long day photosensitive hens, especially within the internal zone. Vimentin expression was similar among groups. However, vimentin-immunoreactive fibers abutting the portal vasculature were significantly negatively correlated with GFAP expression in the median eminence, which is consistent with our hypothesis for a reciprocal relationship between GFAP and vimentin expression. It appears that up-regulation of GFAP expression in the central median eminence of turkey hens is associated with periods of reproductive quiescence and that photofractoriness is associated with the lack of a glial cytoskeletal response to long days.

  8. Managing Colllinearity in Modeling the Effect of Age in the Prediction of Egg Components of Laying Hens Using Stepwise and Ridge Regression Analysis

    Directory of Open Access Journals (Sweden)

    TM Shafey

    2015-12-01

    Full Text Available ABSTRACT The relationships between egg measurements [egg weight (EGWT, egg width (EGWD, egg shape index (EGSI, egg volume (EGV and egg density (EGD], and egg components [eggshell (SWT, yolk (YWT and albumen (AWT] were investigated in laying hens with 32, 45, and 59 weeks of age with an objective of managing multicollinearity (MC, using stepwise regression (SR and ridge regression (RR analyses. There were significant correlations among egg traits that led to MC problems in all eggs. Hen age influenced egg characteristics and the magnitude of the correlations among egg characteristics. Eggs produced at older age had significantly (p<0.01 higher EGWT, EGWD, EGV, YWT and AWT than those produced at younger age. The SR model alleviated MC problem in eggs produced at 32 weeks, with condition index greater than 30, and one predictor, EGWT had a model fit predicted egg components with R2 ranged from 60 to 99%. The SR model of eggs produced at 45 and 59 weeks indicated MC problem with variance inflation factors (VIF values greater than 10, and 4 predictors; EGWT, EGWD, EGV and EGD had a model fit that significantly predicted egg components with R2 % ranged from 76 to 99 %. The RR analysis provided lower VIF values than 10 and eliminated the MC problem for eggs produced at any age group. It is concluded that the RR analysis provided an ideal solution for managing the MC problem and successfully predicting egg components of laying hens from egg measurements.

  9. Structural and biochemical insights into 2′-O-methylation at the 3′-terminal nucleotide of RNA by Hen1

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Chio Mui; Zhou, Chun; Brunzelle, Joseph S.; Huang, Raven H.; (UIUC); (NWU)

    2010-01-28

    Small RNAs of {approx}20-30 nt have diverse and important biological roles in eukaryotic organisms. After being generated by Dicer or Piwi proteins, all small RNAs in plants and a subset of small RNAs in animals are further modified at their 3'-terminal nucleotides via 2'-O-methylation, carried out by the S-adenosylmethionine-dependent methyltransferase (MTase) Hen1. Methylation at the 3' terminus is vital for biological functions of these small RNAs. Here, we report four crystal structures of the MTase domain of a bacterial homolog of Hen1 from Clostridium thermocellum and Anabaena variabilis, which are enzymatically indistinguishable from the eukaryotic Hen1 in their ability to methylate small single-stranded RNAs. The structures reveal that, in addition to the core fold of the MTase domain shared by other RNA and DNA MTases, the MTase domain of Hen1 possesses a motif and a domain that are highly conserved and are unique to Hen1. The unique motif and domain are likely to be involved in RNA substrate recognition and catalysis. The structures allowed us to construct a docking model of an RNA substrate bound to the MTase domain of bacterial Hen1, which is likely similar to that of the eukaryotic counterpart. The model, supported by mutational studies, provides insight into RNA substrate specificity and catalytic mechanism of Hen1.

  10. Modeling complexes of modeled proteins.

    Science.gov (United States)

    Anishchenko, Ivan; Kundrotas, Petras J; Vakser, Ilya A

    2017-03-01

    Structural characterization of proteins is essential for understanding life processes at the molecular level. However, only a fraction of known proteins have experimentally determined structures. This fraction is even smaller for protein-protein complexes. Thus, structural modeling of protein-protein interactions (docking) primarily has to rely on modeled structures of the individual proteins, which typically are less accurate than the experimentally determined ones. Such "double" modeling is the Grand Challenge of structural reconstruction of the interactome. Yet it remains so far largely untested in a systematic way. We present a comprehensive validation of template-based and free docking on a set of 165 complexes, where each protein model has six levels of structural accuracy, from 1 to 6 Å C(α) RMSD. Many template-based docking predictions fall into acceptable quality category, according to the CAPRI criteria, even for highly inaccurate proteins (5-6 Å RMSD), although the number of such models (and, consequently, the docking success rate) drops significantly for models with RMSD > 4 Å. The results show that the existing docking methodologies can be successfully applied to protein models with a broad range of structural accuracy, and the template-based docking is much less sensitive to inaccuracies of protein models than the free docking. Proteins 2017; 85:470-478. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  11. Protein Models Comparator

    CERN Document Server

    Widera, Paweł

    2011-01-01

    The process of comparison of computer generated protein structural models is an important element of protein structure prediction. It has many uses including model quality evaluation, selection of the final models from a large set of candidates or optimisation of parameters of energy functions used in template free modelling and refinement. Although many protein comparison methods are available online on numerous web servers, their ability to handle a large scale model comparison is often very limited. Most of the servers offer only a single pairwise structural comparison, and they usually do not provide a model-specific comparison with a fixed alignment between the models. To bridge the gap between the protein and model structure comparison we have developed the Protein Models Comparator (pm-cmp). To be able to deliver the scalability on demand and handle large comparison experiments the pm-cmp was implemented "in the cloud". Protein Models Comparator is a scalable web application for a fast distributed comp...

  12. Genetic variations alter physiological responses following heat stress in 2 strains of laying hens.

    Science.gov (United States)

    Felver-Gant, J N; Mack, L A; Dennis, R L; Eicher, S D; Cheng, H W

    2012-07-01

    Heat stress (HS) is a major problem experienced by the poultry industry during high-temperature conditions. The ability to manage the detrimental effects of HS can be attributed to multiple factors, including genetic background of flocks. The objective of the present study was to determine the genetic variation in HS effects on laying hens' physiological homeostasis. Ninety 28-wk-old White Leghorn hens of 2 strains were used: a commercial line of individually selected hens for high egg production, DeKalb XL (DXL), and a line of group-selected hens for high productivity and survivability, named kind gentle bird (KGB). Hens were randomly paired by strain and assigned to hot or control treatment for 14 d. Physical and physiological parameters were analyzed at d 8 and 14 posttreatment. Compared with controls, HS increased hen's core body temperature (P hens exposed to HS (P hens, KGB hens had higher heat shock protein 70 concentrations (P hens' liver weight decreased following HS, with less of a response in the KGB line (P hens due to genetic variations. These data provide evidence that is valuable for determining genetic interventions for laying hens under HS.

  13. MODELS OF PROTEIN FOLDING

    Directory of Open Access Journals (Sweden)

    Unnati Ahluwalia

    2012-12-01

    Full Text Available In an attempt to explore the understanding of protein folding mechanism, various models have been proposed in the literature. Advances in recent experimental and computational techniques rationalized our understanding on some of the fundamental features of the protein folding pathways. The goal of this review is to revisit the various models and outline the essential aspects of the folding reaction.

  14. Functional characterization of folic acid transport in the intestine of the laying hen using the everted intestinal sac model.

    Science.gov (United States)

    Tactacan, G B; Rodriguez-Lecompte, J C; Karmin, O; House, J D

    2011-01-01

    Absorption at the level of the intestine is likely a primary regulatory mechanism for the deposition of dietary supplemented folic acid into the chicken egg. Therefore, factors affecting the intestinal transport of folic acid in the laying hen may influence the level of egg folate concentrations. To this end, a series of experiments using intestinal everted sacs were conducted to characterize intestinal folic acid absorption processes in laying hens. Effects of naturally occurring folate derivatives (5-methyl and 10-formyltetrahydrofolate) as well as heme on folic acid absorption were also investigated. Folic acid absorption was measured based on the rate of uptake of (3)H-labeled folic acid in the everted sac from various segments of the small and large intestines. Folic acid concentration, incubation length, and pH condition were optimized before the performance of uptake experiments. The distribution profile of folic acid transport along the intestine was highest in the upper half of the small intestine. Maximum uptake rate (nmol·100 g tissue(-1)·min(-1)) was observed in the duodenum (20.6 ± 1.9) and jejunum (22.3 ± 2.0) and decreased significantly in the ileum (15.3 ± 1.1) and cecum (9.3 ± 0.9). Transport increased proportionately (P laying hen. Uptake of folic acid in the cecum raises the likelihood of absorption of bacterial-derived folate.

  15. Modelling of spatial variation of floor eggs in an aviary house for laying hens

    NARCIS (Netherlands)

    Vroegindeweij, B.A.; Henten, van E.J.; Willigenburg, van L.G.; Groot Koerkamp, P.W.G.

    2013-01-01

    A problem in loose housing systems for layers is laying eggs on the floor, which need manual collection. To automate this, it is desired to know the location of floor eggs for planning a collection path. as this information is not available, we constructed a spatial model to indicate the probability

  16. 吡咯喹啉醌对脂肪肝蛋鸡肝损伤的保护作用机制%Protective Mechanisms of Dietary Pyrroloquinoline Quinine on Fatty Liver Laying Hens

    Institute of Scientific and Technical Information of China (English)

    赵芹; 张海军; 武书庚; 岳洪源; 王晶; 齐广海; 孙琳琳

    2014-01-01

    This experiment was conducted to investigate the protective mechanisms of dietary pyrroloquinoline quinine ( PQQ) on laying hens with fatty liver syndrome. Two hundred and eighty eight Hy-Line brown laying hens aged 29 weeks were randomly divided into 4 groups with 6 replicates per group and 12 hens per replicate. Hens in group Ⅰ (control group) were fed a basal diet (ME 11. 03 MJ/kg; CP 16. 2%), hens in group Ⅱ( pathological model control group ) were fed a high-energy low-protein diet ( ME 12 . 75 MJ/kg; CP 13 . 0%) , and hens in groups Ⅲ and Ⅳ were fed the high-energy low-protein diet ( the same as group Ⅱ) supplemented with 0. 08 or 0. 16 mg/kg PQQ, respectively. The experiment lasted for 4 weeks. The results showed as follows:1) compared with the control group, high-energy low-protein diet in groupⅡsuccessfully induced experimental fatty liver model;there were large quantity of fat degeneration in livers from pathological model control; the contents of triglyceride and total cholesterol in liver, and the plasma alanine aminotrans-ferase activity in groupⅡwere significantly increased ( P0.05)。由此可见,饲粮PQQ可通过改善蛋鸡肝脏线粒体功能、调节脂质代谢和抗氧化功能预防蛋鸡脂肪肝综合征。

  17. Protein Model Database

    Energy Technology Data Exchange (ETDEWEB)

    Fidelis, K; Adzhubej, A; Kryshtafovych, A; Daniluk, P

    2005-02-23

    The phenomenal success of the genome sequencing projects reveals the power of completeness in revolutionizing biological science. Currently it is possible to sequence entire organisms at a time, allowing for a systemic rather than fractional view of their organization and the various genome-encoded functions. There is an international plan to move towards a similar goal in the area of protein structure. This will not be achieved by experiment alone, but rather by a combination of efforts in crystallography, NMR spectroscopy, and computational modeling. Only a small fraction of structures are expected to be identified experimentally, the remainder to be modeled. Presently there is no organized infrastructure to critically evaluate and present these data to the biological community. The goal of the Protein Model Database project is to create such infrastructure, including (1) public database of theoretically derived protein structures; (2) reliable annotation of protein model quality, (3) novel structure analysis tools, and (4) access to the highest quality modeling techniques available.

  18. Shrimp cephalothorax meal in laying hen diets.

    Directory of Open Access Journals (Sweden)

    Catalina Salas-Durán

    2015-06-01

    Full Text Available The aim of this study was to meassure the effect of shrimp meal (SM in commercial laying hen diets. From April to September 2013, in Costa Rica, Pleuroncodes planipes was used to obtain a meal (SM with a yield of 15%, particle size of 256 μg and negative for Salmonella sp. Proximate analysis was performed to the SM: crude protein (40.67%, ether extract (11.05%, crude fiber (7.12%, ash (27.48%, calcium (9.03%, phosphorus (2.66%, amino acid profile, pepsin digestibility (84% and acidity (8.34. Subsequently, a trial was performed with 140 40-week-old Hy-Line Brown laying hens, fed with four different diets containing increasing levels of inclusion of SM (0%, 5%, 10%, and 15% during four weeks; and formulated according to the ideal protein and digestible amino acids concepts; being isocaloric and isoproteic. The variables experimentally evaluated were: production percentage, feed intake, body weight, mortality, egg weight and feed conversion ratio. Only egg weight changed significantly between treatments in the third week (p<0.05. The hens fed with 5% SM laid heavier eggs. It is suggested to evaluate a level of SM inclusion up to 15% in laying hens diets.

  19. Behavioral differences of laying hens with fractured keel bones within furnished cages

    Directory of Open Access Journals (Sweden)

    Teresa Marie Casey-Trott

    2016-05-01

    Full Text Available High prevalence of keel bone fractures in laying hens is reported in all housing systems. Keel fractures have been associated with pain and restricted mobility in hens in loose housing. The objective was to determine whether keel fractures were associated with activity of hens in furnished cages. Thirty-six pairs of LSL Lite hens (72 wk were enrolled in the study. One hen with a fractured keel and one hen without were identified by palpation in each of 36 groups of hens housed in either 30 or 60-bird cages stocked at 750cm2/hen. Behavioral activity of each hen was recorded by four observers blind to keel status using focal animal sampling for 10 min within a 2 hr period in the morning (08:00-10:00, afternoon (12:00-14:00, and evening (17:00-19:00. All hens were observed during each of the three sample periods for three days totaling 90 min, and individual hen data was summed for analysis. Hens were euthanized 48hr after final observations, dissected, and classified by keel status: F0 (no fracture, N=24; F1 (single fracture, N=17; F2 (multiple fractures, N=31. The percentages of time hens performed each behavior were analyzed using a mixed procedure in SAS with fracture severity, body weight, cage size, rearing environment, and tier in the model. Fracture severity affected the duration of perching (P=0.04 and standing (P=0.001, bout length of standing (P<0.0001, and location (floor vs perch of resting behaviors (P=0.01. F2 hens perched longer than F0 hens, 20.0% ± 2.9 and 11.6% ± 3.2. F2 hens spent less time standing, 15.2% ± 1.5, than F0 and F1 hens, 20.7% ± 1.6 and 21.6% ± 1.8. F2 hens had shorter standing bouts (22.0 sec ± 4.2 than both F0 and F1 hens, 33.1 sec ± 4.3 and 27.4 sec ± 4.4. Non-fractured hens spent 80.0% ± 6.9 of total resting time on the floor whereas F1 and F2 hens spent 56.9% ± 12.4 and 51.5% ± 7.7, resting on the floor. Behavioral differences reported here provide insight into possible causes of keel damage, or

  20. Lieb-Liniger-like model of quantum solvation in CO-(4)HeN clusters.

    Science.gov (United States)

    Farrelly, D; Iñarrea, M; Lanchares, V; Salas, J P

    2016-05-28

    Small (4)He clusters doped with various molecules allow for the study of "quantum solvation" as a function of cluster size. A peculiarity of quantum solvation is that, as the number of (4)He atoms is increased from N = 1, the solvent appears to decouple from the molecule which, in turn, appears to undergo free rotation. This is generally taken to signify the onset of "microscopic superfluidity." Currently, little is known about the quantum mechanics of the decoupling mechanism, mainly because the system is a quantum (N + 1)-body problem in three dimensions which makes computations difficult. Here, a one-dimensional model is studied in which the (4)He atoms are confined to revolve on a ring and encircle a rotating CO molecule. The Lanczos algorithm is used to investigate the eigenvalue spectrum as the number of (4)He atoms is varied. Substantial solvent decoupling is observed for as few as N = 5 (4)He atoms. Examination of the Hamiltonian matrix, which has an almost block diagonal structure, reveals increasingly weak inter-block (solvent-molecule) coupling as the number of (4)He atoms is increased. In the absence of a dopant molecule the system is similar to a Lieb-Liniger (LL) gas and we find a relatively rapid transition to the LL limit as N is increased. In essence, the molecule initially-for very small N-provides a central, if relatively weak, attraction to organize the cluster; as more (4)He atoms are added, the repulsive interactions between the identical bosons start to dominate as the solvation ring (shell) becomes more crowded which causes the molecule to start to decouple. For low N, the molecule pins the atoms in place relative to itself; as N increases the atom-atom repulsion starts to dominate the Hamiltonian and the molecule decouples. We conclude that, while the notion of superfluidity is a useful and correct description of the decoupling process, a molecular viewpoint provides complementary insights into the quantum mechanism of the transition from a

  1. Feather loss in laying hens

    Directory of Open Access Journals (Sweden)

    Hristov Slavča

    2006-01-01

    Full Text Available The paper examined the incidence of different forms of feather loss and cannibalism in laying hens aged 74 weeks following moulting and in laying hens following exploitation for a period of one year. The forms of feather loss were considered in detail through a repeated examination of video recordings and they were sorted according to localization - to feather loss on the ventral part of the neck, on the dorsal part of the neck, and on the back between the wings. Feather loss on the ventral part of the neck was established in 47.9% hens, and in the dorsal part in 16.77% hens of the 167 laying hens aged 74 weeks following moulting. The group of 129 laying hens that were observed following one-year exploitation exhibited considerably more frequent feather loss, in 96.90% hens it was localized on the ventral part of the neck, in 60.47% hens on the dorsal part of the neck, and in 20.16% hens it was localized on the back between the wings. A comparison of the results of the incidence of co localized forms of feather loss in the one and the other group of laying hens using the t-test showed statistically very significant differences. A detailed consideration of the video recordings using the method of sequence analysis did not reveal any cannibalism in either group of laying hens.

  2. Cu influence on hens weight

    Science.gov (United States)

    Afonina, I. A.; Kleptsyna, E. S.; Petukhov, V. L.; Patrashkov, S. A.

    2003-05-01

    Copper plays an important part in living being bodies. But, both high and low Cu levels may cause human and animal diseases. Some East Siberia areas are characterized by Cu pollution [1]. 5 group of hens were formed: 1 - control, 2-5 - experimental. For a month the hens from experimental groups were drunk with water where Cu content was 5, 10, 20 and 30 times higher than the upper limits (UL). Group 1 - 3 hens' weight was almost the same during the experiment. Weight decrease (from 2020 to 1656 g) was detected in group 4 (20 UL) for the first half a month. All the hens of group 4 except for 3 hens were died for the last 2 weeks. In group 5 (30 UL) all the hens died after 2 ... 14 days. Thus, high Cu concentrations (20 ... 30 UL) cause hens' weight reduction of and their death.

  3. Henning Bergenholtz: Bibliovita

    DEFF Research Database (Denmark)

    2009-01-01

    Henning Bergenholtz's list of publication is so long and he has addressed so many topics that the best way in which to do him justice is to list the most important of his published works chronologically. This temporal presentation also gives an indication of the long period in which he has contri...

  4. Effect of Dietary Crude Protein and Methionine on Egg Production and Egg Quality of Laying Hens During Phase II

    Directory of Open Access Journals (Sweden)

    H Mohammadi Emarat

    2012-02-01

    Full Text Available An experiment was conducted to evaluate the effect of dietary crude protein and methionine levels on quality and quantity of egg production. Fifteen diets formulated with 3 levels of protein (13, 14 and 15% and 5 levels of methionine (0.25, 0.28, 0.31, 0.34 and 0.37% and fed to 420 birds in a 3×5 factorial arrangement. Each diet was randomly fed to 4 replicates of 7 birds each and fed for 3 periods of 4 weeks (50-62wks of age each. Egg number and mortality was recorded daily, whereas feed consumption determined at the end of each period. The increased in dietary protein significantly increased egg production from 54 to 59.4 %. Egg weight, egg mass and feed intake increased by 1.7 g, 3.4 g, and 2.8 g, respectively during the whole experimental period. As the dietary protein increased, feed conversion, egg component (as a percent of whale egg and egg albumin percent were improved. However, the egg breaking, specific gravity and eggshell were significantly decreased with increased dietary protein. The egg yolk percent was not influenced by dietary protein levels. The increased in dietary methionine from 0.25% to 0.37% caused the overall egg production, egg weight, egg mass, feed intake and egg component to improve by about 8.2%, 4g, 6.6g, 8.7g, and 6.0g, respectively. Feed conversion, specific gravity, egg breakage, egg shell, and egg yolk and albumin percent were not influenced by dietary methionine levels.

  5. Association of Immunosuppression with DR6 Expression during the Development and Progression of Spontaneous Ovarian Cancer in Laying Hen Model.

    Science.gov (United States)

    McNeal, Sa'Rah; Bitterman, Pincas; Bahr, Janice M; Edassery, Seby L; Abramowicz, Jacques S; Basu, Sanjib; Barua, Animesh

    2016-01-01

    Ovarian cancer (OVCA) mainly disseminates in the peritoneal cavity. Immune functions are important to prevent OVCA progression and recurrence. The mechanism of immunosuppression, a hallmark of tumor progression, is not well understood. The goal of this study was to determine the immune system's responses and its suppression during OVCA development and progression in hens. Frequencies of CD8+ T cells and IgY-containing cells and expression of immunosuppressors including IRG1 and DR6 in OVCA at early and late stages in hens were examined. Frequencies of stromal but not the intratumoral CD+8 T cells and IgY-containing cells increased significantly (P < 0.01) during OVCA development and progression. Tumor progression was associated with increased expression of IRG1 and DR6 and decreased infiltration of immune cells into the tumor. Frequency of stromal but not intratumoral immune cells increases during OVCA development and progression. Tumor-induced IRG1 and DR6 may prevent immune cells from invading the tumor.

  6. Modeling Mercury in Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Jeremy C [ORNL; Parks, Jerry M [ORNL

    2016-01-01

    Mercury (Hg) is a naturally occurring element that is released into the biosphere both by natural processes and anthropogenic activities. Although its reduced, elemental form Hg(0) is relatively non-toxic, other forms such as Hg2+ and, in particular, its methylated form, methylmercury, are toxic, with deleterious effects on both ecosystems and humans. Microorganisms play important roles in the transformation of mercury in the environment. Inorganic Hg2+ can be methylated by certain bacteria and archaea to form methylmercury. Conversely, bacteria also demethylate methylmercury and reduce Hg2+ to relatively inert Hg(0). Transformations and toxicity occur as a result of mercury interacting with various proteins. Clearly, then, understanding the toxic effects of mercury and its cycling in the environment requires characterization of these interactions. Computational approaches are ideally suited to studies of mercury in proteins because they can provide a detailed picture and circumvent issues associated with toxicity. Here we describe computational methods for investigating and characterizing how mercury binds to proteins, how inter- and intra-protein transfer of mercury is orchestrated in biological systems, and how chemical reactions in proteins transform the metal. We describe quantum chemical analyses of aqueous Hg(II), which reveal critical factors that determine ligand binding propensities. We then provide a perspective on how we used chemical reasoning to discover how microorganisms methylate mercury. We also highlight our combined computational and experimental studies of the proteins and enzymes of the mer operon, a suite of genes that confers mercury resistance in many bacteria. Lastly, we place work on mercury in proteins in the context of what is needed for a comprehensive multi-scale model of environmental mercury cycling.

  7. Correction of metabolism with using of biologically active matters for laying hens

    Directory of Open Access Journals (Sweden)

    E. A. Loseva

    2005-05-01

    Full Text Available This paper presents the results of investigations from the application of hydrohumateas an addi-tive to poor-quality rations for eaying hens of Loghmann Broun cross in their 2nd phase of egg laing. Effect of optimal doses hydrohumate on the level of protein metabolism and productive qualities of laying hens was established.

  8. Oral food desensitization in children with IgE-mediated hen's egg allergy: a new protocol with raw hen's egg.

    Science.gov (United States)

    Meglio, Paolo; Giampietro, Paolo G; Carello, Rossella; Gabriele, Ida; Avitabile, Simona; Galli, Elena

    2013-02-01

    Hen's egg allergy affects young children and can cause severe allergic reactions. Avoidance results in dietary limitations and can affect the quality of life, especially in cases where potentially life-threatening reactions exist. Our objective was to desensitize children with moderate-severe IgE-mediated hen's egg allergy over a 6-month period, by introducing increasing and very gradual daily doses of raw hen's egg in order to enable the children to assume 25ml of this food, or to induce tolerance to the highest possible dose. The protocol foresaw the egg reintroduction in the home setting. In this randomized, controlled open study, 20 hen's egg allergic children (10 in the active group) were admitted. A convincing history or a positive double-blind placebo-controlled food challenge confirmed the diagnosis. Oral desensitization was performed with increasing doses starting from 0.27 mg of hen's egg proteins (1 drop of raw hen's egg diluted 1:100). We adopted an original, mathematically calculated protocol in order to ensure a constant, daily increment of doses. 8/10 children (80%) in the active group achieved the daily intake of 25ml over a 6-month period. One child (10%) could tolerate up to 2ml/day while another child (10%) failed the desensitization. Six months after enrolment only 2 children in the control group (20%) could tolerate hen's egg. We successfully desensitized 8/10 children with IgE-mediated hen's egg allergy in a 6-month period. The partial outcome in the child who could tolerate 2ml/day reduced the risk of severe reactions after unnoticed introduction of egg. A regular protocol that ensures a daily constant increase of doses helps to reduce possible adverse events, thus improving safety and effectiveness. © 2012 John Wiley & Sons A/S.

  9. Multiscale modeling of proteins.

    Science.gov (United States)

    Tozzini, Valentina

    2010-02-16

    The activity within a living cell is based on a complex network of interactions among biomolecules, exchanging information and energy through biochemical processes. These events occur on different scales, from the nano- to the macroscale, spanning about 10 orders of magnitude in the space domain and 15 orders of magnitude in the time domain. Consequently, many different modeling techniques, each proper for a particular time or space scale, are commonly used. In addition, a single process often spans more than a single time or space scale. Thus, the necessity arises for combining the modeling techniques in multiscale approaches. In this Account, I first review the different modeling methods for bio-systems, from quantum mechanics to the coarse-grained and continuum-like descriptions, passing through the atomistic force field simulations. Special attention is devoted to their combination in different possible multiscale approaches and to the questions and problems related to their coherent matching in the space and time domains. These aspects are often considered secondary, but in fact, they have primary relevance when the aim is the coherent and complete description of bioprocesses. Subsequently, applications are illustrated by means of two paradigmatic examples: (i) the green fluorescent protein (GFP) family and (ii) the proteins involved in the human immunodeficiency virus (HIV) replication cycle. The GFPs are currently one of the most frequently used markers for monitoring protein trafficking within living cells; nanobiotechnology and cell biology strongly rely on their use in fluorescence microscopy techniques. A detailed knowledge of the actions of the virus-specific enzymes of HIV (specifically HIV protease and integrase) is necessary to study novel therapeutic strategies against this disease. Thus, the insight accumulated over years of intense study is an excellent framework for this Account. The foremost relevance of these two biomolecular systems was

  10. Henning Bergenholtz: Bibliovita

    DEFF Research Database (Denmark)

    2009-01-01

    Henning Bergenholtz's list of publication is so long and he has addressed so many topics that the best way in which to do him justice is to list the most important of his published works chronologically. This temporal presentation also gives an indication of the long period in which he has...... of languages include books and papers on the development of theories and principles for the compilation of dictionaries as well as reviews of dictionaries and monographs in a constant quest to learn from other scholars. The dictionaries he has authored and co-authored cover the spectrum from monolingual...

  11. Effects of Qyrroloquinoline Quinine on Performance, Egg Quality, Plasma Lipid Metabolism and Antioxidant Ability of Laying Hens Fed High-Energy Low-Protein Diets%吡咯喹啉醌对高能低蛋白质饲粮蛋鸡生产性能、蛋品质、血浆脂质代谢及抗氧化能力的影响

    Institute of Scientific and Technical Information of China (English)

    赵芹; 张海军; 武书庚; 岳洪源; 王晶; 齐广海; 孙琳琳

    2014-01-01

    This experiment was conducted to investigate the effects of pyrroloquinoline quinine ( PQQ) on per-formance, egg quality, plasma lipid metabolism and antioxidant ability of laying hens fed high-energy low-pro-tein diets. Two hundred and eighty-eight Hy-Line brown laying hens aged 29 weeks were randomly divided in-to 4 groups with 6 replicates per group and 12 hens per replicate. Hens in group Ⅰ ( control group) were fed a basal diet ( metabolic energy 11 . 03 MJ/kg; crude protein 16 . 2%) , hens in group II ( pathological model control group) were fed a high-energy low-protein diet ( metabolic energy 12. 75 MJ/kg; crude protein 13 . 0%) , and hens in groups Ⅲ and Ⅳ were fed the high-energy low-protein diet ( the same as group II) supplemented with 0. 08 and 0. 16 mg/kg PQQ, respectively. The experiment lasted for 4 weeks. The results showed as follows:1) compared with the control group, the high-energy low-protein diet induced fatty liver, the liver fat rate in group II was significantly increased (P<0. 05), and the contents of triglyceride (TG), total cholesterol ( TC) and low-density lipoprotein cholesterol ( LDL-C) in plasma in group II were signifi-cantly increased ( P<0 . 05 ) . 2 ) Dietary PQQ could significantly decrease the increase of average daily feed intake and the ratio of feed to egg of laying hens fed high-energy low-protein diets ( P<0 . 05 ) , it could signif-icantly inhibit the decrease of albumen height, Haugh unit and yolk color and the increase of the contents of TG, TC and LDL-C and lactate dehydrogenase (LDH) activity in plasma (P<0. 05), and all the above inde-xes could get the same levels as control group. 3) Dietary PQQ could significantly inhibit the decrease of plas-ma superoxide dismutase activity and the increase of plasma malondialdehyde content of laying hens fed high-energy low-protein diets (P<0. 05). In conclusion, dietary PQQ can decrease the liver fat content, improve the lipid metabolism and antioxidant ability of laying

  12. The development of imitation crab sticks by substituting spent laying hen meat for Alaska pollack.

    Science.gov (United States)

    Jin, S K; Hur, I C; Jeong, J Y; Choi, Y J; Choi, B D; Kim, B G; Hur, S J

    2011-08-01

    Imitation crab stick (ICS) samples were divided into 5 treatments, a control composed of commercial ICS containing no breast meat from spent laying hens, and treatments 1, 2, 3, and 4, in which 5, 10, 15, and 20% batter from breast meat of whole spent laying hens was substituted for Alaska pollack surimi, respectively. Imitation crab stick samples containing spent laying hen breast meat batter showed significantly (P 0.05) among ICS samples. During storage, whiteness was greater in the control sample than in the ICS samples containing spent laying hen breast meat batter. The saturated and monounsaturated fatty acids increased, whereas the polyunsaturated fatty acids decreased in response to substituting surimi with spent laying hen breast meat batter. The moisture content and pH were increased as the amount of spent laying hen breast meat batter increased. The lipid oxidation value (TBA-reactive substances) and protein degradation value (volatile basic nitrogen) tended to increase during storage as the amount of spent laying hen breast meat batter increased. None of the sensory evaluation items differed among ICS samples during storage, although the color of the final products, mechanical color (by colorimeter), and textural properties did differ among samples. These results indicate that substituting laying hen breast meat batter for Alaska pollack surimi is a very useful method for the production of ICS because it enables the use of a simple production process that does not require steps, such as washing or pH adjustment, for myofibrillar protein recovery.

  13. Herbal adaptogens combined with protein fractions from bovine colostrum and hen egg yolk reduce liver TNF-α expression and protein carbonylation in Western diet feeding in rats.

    Science.gov (United States)

    Mobley, C Brooks; Toedebusch, Ryan G; Lockwood, Christopher M; Heese, Alexander J; Zhu, Conan; Krieger, Anna E; Cruthirds, Clayton L; Hofheins, John C; Company, Joseph M; Wiedmeyer, Charles E; Kim, Dae Y; Booth, Frank W; Roberts, Michael D

    2014-01-01

    We examined if a purported anti-inflammatory supplement (AF) abrogated Western-diet (WD)-induced liver pathology in rats. AF contained: 1) protein concentrates from bovine colostrum and avian egg yolk; 2) herbal adaptogens and antioxidants; and 3) acetyl-L-carnitine. Nine month-old male Brown Norway rats were allowed ad libitum access to WD for 41-43 days and randomly assigned to WD + AF feeding twice daily for the last 31-33 days (n = 8), or WD and water-placebo feeding twice daily for the last 31-33 days (n = 8). Rats fed a low-fat/low-sucrose diet (CTL, n = 6) for 41-43 days and administered a water-placebo twice daily for the last 31-33 days were also studied. Twenty-four hours following the last gavage-feed, liver samples were analyzed for: a) select mRNAs (via RT-PCR) as well as genome-wide mRNA expression patterns (via RNA-seq); b) lipid deposition; and, c) protein carbonyl and total antioxidant capacity (TAC). Serum was also examined for TAC, 8-isoprostane and clinical chemistry markers. WD + AF rats experienced a reduction in liver Tnf-α mRNA (-2.8-fold, p < 0.01). Serum and liver TAC was lower in WD + AF versus WD and CTL rats (p < 0.05), likely due to exogenous antioxidant ingredients provided through AF as evidenced by a tendency for mitochondrial SOD2 mRNA to increase in WD + AF versus CTL rats (p = 0.07). Liver fat deposition nor liver protein carbonyl content differed between WD + AF versus WD rats, although liver protein carbonyls tended to be lower in WD + AF versus CTL rats (p = 0.08). RNA-seq revealed that 19 liver mRNAs differed between WD + AF versus WD when both groups were compared with CTL rats (+/- 1.5-fold, p < 0.01). Bioinformatics suggest that AF prevented WD-induced alterations in select genes related to the transport and metabolism of carbohydrates in favor of select genes related to lipid transport and metabolism. Finally, serum clinical safety markers and liver pathology

  14. Modelling of proteins in membranes

    DEFF Research Database (Denmark)

    Sperotto, Maria Maddalena; May, S.; Baumgaertner, A.

    2006-01-01

    This review describes some recent theories and simulations of mesoscopic and microscopic models of lipid membranes with embedded or attached proteins. We summarize results supporting our understanding of phenomena for which the activities of proteins in membranes are expected to be significantly...... affected by the lipid environment. Theoretical predictions are pointed out, and compared to experimental findings, if available. Among others, the following phenomena are discussed: interactions of interfacially adsorbed peptides, pore-forming amphipathic peptides, adsorption of charged proteins onto...... oppositely charged lipid membranes, lipid-induced tilting of proteins embedded in lipid bilayers, protein-induced bilayer deformations, protein insertion and assembly, and lipid-controlled functioning of membrane proteins....

  15. Use of multienzimatic mix on sorghum-soybean meal based ration on hen performance

    Directory of Open Access Journals (Sweden)

    José-Rogelio Orozco-Hernández

    2011-04-01

    Full Text Available The use of individual enzymes in the diet of hens has shown an improvement in egg production, and mixtures are now being included to increase feed utilisation and impact on performance in hens. The objective of our study was to evaluate the use of an enzyme blend in a sorghum-soymeal-based ration (protein 17.5% and ME 2900 kcal/kg on performance. Hens of two lines: Hy-line (n=732 and Bovans white (n=365, aged eighteen weeks, were used to evaluated three treatments (control, Ronozyme blend or Cybenza. The birds were lodged in cages with a density of 485 cm2 per hen (four hens per cage. There were no differences (P>0.05 among enzymatic treatments or their interactions with the hen line on egg yield, egg mass, feed-to-egg ratio, or egg quality. However, the efficiency was higher with Hy-line (P0.05. Based on our results, we concluded that the use of a multi-enzyme mixture in a sorghum-soymeal-based hen feed has a minor effect on performance, regardless of hen genetics.

  16. Performance and egg quality of aged laying hens fed diets ...

    African Journals Online (AJOL)

    p2492989

    principal objective of MBM supplementation to poultry diets is to benefit from MBM's high protein, ... Four hundred and thirty-two 85-week old layer hens of a brown egg layer strain ... Institutional Animal Care and Use Committee approved the techniques and .... Duncan's multiple range test was carried out to detect the ...

  17. Outdoor stocking density in free-range laying hens: radio-frequency identification of impacts on range use.

    Science.gov (United States)

    Campbell, D L M; Hinch, G N; Dyall, T R; Warin, L; Little, B A; Lee, C

    2017-01-01

    The number and size of free-range laying hen (Gallus gallus domesticus) production systems are increasing within Australia in response to consumer demand for perceived improvement in hen welfare. However, variation in outdoor stocking density has generated consumer dissatisfaction leading to the development of a national information standard on free-range egg labelling by the Australian Consumer Affairs Ministers. The current Australian Model Code of Practice for Domestic Poultry states a guideline of 1500 hens/ha, but no maximum density is set. Radio-frequency identification (RFID) tracking technology was used to measure daily range usage by individual ISA Brown hens housed in six small flocks (150 hens/flock - 50% of hens tagged), each with access to one of three outdoor stocking density treatments (two replicates per treatment: 2000, 10 000, 20 000 hens/ha), from 22 to 26, 27 to 31 and 32 to 36 weeks of age. There was some variation in range usage across the sampling periods and by weeks 32 to 36 individual hens from the lowest stocking density on average used the range for longer each day (Pcommercial free-range laying hens but further research would be needed to determine the effects of increased range usage on hen welfare.

  18. Behavioral Differences of Laying Hens with Fractured Keel Bones within Furnished Cages

    Science.gov (United States)

    Casey-Trott, Teresa M.; Widowski, Tina M.

    2016-01-01

    High prevalence of keel bone fractures in laying hens is reported in all housing systems. Keel fractures have been associated with pain and restricted mobility in hens in loose housing. The objective was to determine whether keel fractures were associated with activity of hens in furnished cages. Thirty-six pairs of LSL-Lite hens (72 weeks) were enrolled in the study. One hen with a fractured keel and one hen without were identified by palpation in each of 36 groups of hens housed in either 30- or 60-bird cages stocked at 750 cm2/hen. Behavioral activity of each hen was recorded by four observers blind to keel status using focal animal sampling for 10 min within a 2-h period in the morning (08:00–10:00), afternoon (12:00–14:00), and evening (17:00–19:00). All hens were observed during each of the three sample periods for 3 days totaling 90 min, and individual hen data were summed for analysis. Hens were euthanized 48 h after final observations, dissected, and classified by keel status: F0 (no fracture, N = 24), F1 (single fracture, N = 17), and F2 (multiple fractures, N = 31). The percentages of time hens performed each behavior were analyzed using a mixed procedure in SAS with fracture severity, body weight, cage size, rearing environment, and tier in the model. Fracture severity affected the duration of perching (P = 0.04) and standing (P = 0.001), bout length of standing (P < 0.0001), and location (floor vs. perch) of resting behaviors (P = 0.01). F2 hens perched longer than F0 hens, 20.0 ± 2.9 and 11.6 ± 3.2%. F2 hens spent less time standing, 15.2 ± 1.5%, than F0 and F1 hens, 20.7 ± 1.6 and 21.6 ± 1.8%. F2 hens had shorter standing bouts (22.0 ± 4.2 s) than both F0 and F1 hens, 33.1 ± 4.3 and 27.4 ± 4.4 s. Non-fractured hens spent 80.0 ± 6.9% of total resting time on the floor, whereas F1 and F2 hens spent 56.9 ± 12.4 and 51.5 ± 7.7% resting on the floor

  19. Cyclooxygenases expression and distribution in the normal ovary and their role in ovarian cancer in the domestic hen (Gallus domesticus).

    Science.gov (United States)

    Hales, Dale Buchanan; Zhuge, Yan; Lagman, Jo Ann Jaen; Ansenberger, Kristine; Mahon, Cassandra; Barua, Animesh; Luborsky, Judith L; Bahr, Janice M

    2008-06-01

    Cyclooxygenase (COX) (PTGS) is the rate-limiting enzyme in the biosynthesis of prostaglandins. Two COX isoforms have been identified, COX-1 and COX-2, which show distinct cell-specific expression and regulation. Ovarian cancer is the most lethal gynecological malignancy and the disease is poorly understood due to the lack of suitable animal models. The laying hen spontaneously develops epithelial ovarian cancer with few or no symptoms until the cancer has progresses to a late stage, similar to the human disease. The purpose of this study was to examine the relative expression and distribution of COX-1 and COX-2 in the ovaries of normal hens and in hens with ovarian cancer. The results demonstrate that COX-1 was localized to the granulosa cell layer and cortical interstitium, ovarian surface epithelium (OSE) and postovulatory follicle (POF) of the normal ovary. In ovarian cancer, COX-1 mRNA was significantly increased and COX-1 protein was broadly distributed throughout the tumor stroma. COX-2 protein was localized to the granulosa cell layer in the follicle and the ovarian stroma. COX-2 mRNA expression did not change as a function of age or in ovarian cancer. There was significantly higher expression of COX-1 mRNA in the first POF (POF-1) compared to POF-2 and POF-3. COX-2 mRNA expression was not significantly different among POFs. There was no difference in COX-1 or COX-2 mRNA in the OSE isolated from individual follicles in the follicular hierarchy. The results confirm previous findings of the high expression of COX-1 in ovarian tumors further supporting the laying hen as a model for ovarian cancer, and demonstrate for the first time the high expression of COX-1 in POF-1 which is the source of prostaglandins needed for oviposition.

  20. Comparative Protein Structure Modeling Using MODELLER.

    Science.gov (United States)

    Webb, Benjamin; Sali, Andrej

    2016-06-20

    Comparative protein structure modeling predicts the three-dimensional structure of a given protein sequence (target) based primarily on its alignment to one or more proteins of known structure (templates). The prediction process consists of fold assignment, target-template alignment, model building, and model evaluation. This unit describes how to calculate comparative models using the program MODELLER and how to use the ModBase database of such models, and discusses all four steps of comparative modeling, frequently observed errors, and some applications. Modeling lactate dehydrogenase from Trichomonas vaginalis (TvLDH) is described as an example. The download and installation of the MODELLER software is also described. © 2016 by John Wiley & Sons, Inc.

  1. Modelling hen harrier dynamics to inform human-wildlife conflict resolution: a spatially-realistic, individual-based approach

    National Research Council Canada - National Science Library

    Heinonen, Johannes P M; Palmer, Stephen C F; Redpath, Steve M; Travis, Justin M J

    2014-01-01

    Individual-based models have gained popularity in ecology, and enable simultaneous incorporation of spatial explicitness and population dynamic processes to understand spatio-temporal patterns of populations...

  2. Flaxseed enriched diet-mediated reduction in ovarian cancer severity is correlated to the reduction of prostaglandin E(2) in laying hen ovaries.

    Science.gov (United States)

    Eilati, Erfan; Hales, Karen; Zhuge, Yan; Ansenberger Fricano, Kristine; Yu, Rui; van Breemen, Richard B; Hales, Dale Buchanan

    2013-09-01

    Prevention of ovarian cancer is the best approach for reducing the impact of this deadly disease. The laying hen is a robust model of spontaneous ovarian cancer that recapitulates the human disease. Dietary intervention with flaxseed, the richest vegetable source of omega-3 fatty acids (OM-3FAs) and phytoestrogen lignans, demonstrate the potential for effective prevention and amelioration of ovarian cancer by targeting inflammatory prostaglandin pathways. Prostaglandin E2 (PGE2) is the most pro-inflammatory ecoisanoid and one of the downstream products of two isoforms of cyclooxygenase (COX) enzymes: COX-1 and COX-2. Our objective was to investigate the effect of flaxseed supplementation for one year on ovarian cancer and correlate its effects to expression of COX enzymes and concentrations of prostaglandins. White Leghorn hens were fed 10% flaxseed-enriched or standard diet for one year. The severity of ovarian cancer was determined by gross pathology and histology. COX-1 and COX-2 localization and protein and mRNA expression and PGE2 and PGE3 concentrations in ovaries were measured by IHC, western blot, quantitative real-time PCR and LC-MS-MS, respectively. The results demonstrated a significant reduction in late stage ovarian tumors in the flaxseed-fed hens compared with the control diet-fed hens. In correlation with decreased ovarian cancer severity, concentrations of PGE2 and expression of COX-2 were diminished in ovaries of flaxseed-fed hens. PGE3 concentrations were below the level of detection. The results demonstrated that in normal ovaries, COX-1 was localized to the granulosa cell layer surrounding the follicles and ovarian surface epithelium (OSE) whereas COX-2 protein was localized to the granulosa cell layer in the follicle. Extensive COX-1 and COX-2 protein expression was found throughout the ovarian carcinoma. Our findings suggest that the flaxseed-mediated reduction in the severity of ovarian cancer in hens is correlated to the reduction in PGE2 in

  3. Effect of Quercetin on Egg Quality and Components in Laying Hens of Different Weeks

    Institute of Scientific and Technical Information of China (English)

    You Ying; Han Chun-yan; ChaudhrYMaria Tabassum; Li Ling; Yao Jia-ying; Wang Sheng-nan; Yang Jia-xin; Teng Nan; Li Yao

    2015-01-01

    This trial was conducted to evaluate the effect of quercetin on egg quality and components in laying hens of different weeks. A total of 240 healthy Hessian laying hens at 29, 39-week-old with similar body weight and laying rate were randomly divided into four groups with six replicates of 10 each replicate, respectively. The treatments were fed with basal diet supplemented with 0, 0.2, 0.4 and 0.6 g•kg-1 quercetin for 8 weeks. The results showed that compared with the control, broken or soft shell rate significantly decreased at 0.2 and 0.4 g•kg-1 quercetin and eggshell thickness significantly increased at 0.4 g•kg-1 quercetin (P<0.01) in laying hens at 39-47 weeks old; yolk protein significantly decreased at 0.6 g•kg-1 quercetin (P<0.05) in laying hens at 29-37 weeks old; while yolk protein significantly increased at three quercetin treatments in laying hens at 39-47 weeks old; yolk cholesterol significantly decreased by quercetin in laying hens at 29-37 weeks old (P<0.05); yolk total phospholipids significantly increased at 0.4 and 0.6 g•kg-1 quercetin (P<0.01) and yolk cholesterol significantly decreased at 0.6 g•kg-1 quercetin (P<0.05) in laying hens at 39-47 weeks old. In a word, quercetin affected egg quality and components to some extents in laying hens of different weeks, the older the hens became, the better improvement they would be. The optimum level of quercetin was 0.4 g•kg-1 in the basal diet.

  4. Comparison of extraction conditions for milk and hen's egg allergens

    OpenAIRE

    2011-01-01

    Abstract The evaluation of recovery rates extracting dried milk and egg powder using eleven different extractants led to approximately similar results for both foods. Compared to the other extraction solutions investigated, ?1% Tween 20 and 0.4% Triton X-100? and ?4 % SDS? are the most qualified extractants to isolate proteins of hen's egg or milk. Comparing calculated protein recovery rates of egg and milk powder extracts the results clearly indicate that the choice of a suitable ...

  5. Carnitine supplementation modulates high dietary copper-induced oxidative toxicity and reduced performance in laying hens.

    Science.gov (United States)

    Güçlü, Berrin Kocaoğlu; Kara, Kanber; Çakır, Latife; Çetin, Ebru; Kanbur, Murat

    2011-12-01

    This experiment was conducted to evaluate the effects of L-carnitine on performance, egg quality and certain biochemical parameters in laying hens fed a diet containing high levels of copper proteinate. Forty-eight 42-week-old laying hens were divided into four groups with four replicates. The laying hens were fed with a basal diet (control) or the basal diet supplemented with either 400 mg carnitine (Car)/kg diet, 800 mg copper proteinate (CuP)/kg diet or 400 mg carnitine + 800 mg copper (Car+CuP)/kg diet, for 6 weeks. Supplemental CuP decreased feed consumption (p supplemental CuP and Car+CuP. Supplemental CuP caused an increase in plasma malondialdehyde (p carnitine and copper combination may prevent the possible adverse effects of high dietary copper on performance and lipid peroxidation in hens.

  6. Modelling of proteins in membranes

    DEFF Research Database (Denmark)

    Sperotto, Maria Maddalena; May, S.; Baumgaertner, A.

    2006-01-01

    This review describes some recent theories and simulations of mesoscopic and microscopic models of lipid membranes with embedded or attached proteins. We summarize results supporting our understanding of phenomena for which the activities of proteins in membranes are expected to be significantly ...

  7. 不同蛋白来源对京红蛋鸡生产性能及蛋品质的影响%Effect of Dietary Protein Sources on Egg Performance and Egg Quality of Jinghong Laying Hens at Peak Production

    Institute of Scientific and Technical Information of China (English)

    王晓翠; 张海军; 武书庚; 岳洪源; 李杰; 齐广海

    2015-01-01

    3.41%(P=0.091),4%黄粉虫组提高3.87%(P=0.079);试验期内各处理组蛋白pH均无显著差异(P>0.05)。(4)4 w末,与豆粕组相比,棉籽蛋白组和双低菜粕组的蛋清比例分别降低1.67%和1.18%(P=0.099),4%黄粉虫组提高1.70%(P=0.099);4%黄粉虫组蛋黄干物质含量显著高于菜粕组(P<0.05)。【结论】对于京红1号高峰产蛋鸡而言,在日粮等能、等氮、相同可消化氨基酸模式下,棉籽蛋白和双低菜粕可降低日产蛋量,降低日采食量和饲料效率,同时降低蛋白高度及哈氏单位等。可见,豆粕及4%黄粉虫部分替代豆粕较适合作为其蛋白源饲料,双低菜粕和脱酚棉籽蛋白稍次。%Objective] This experiment was conducted to evaluate the effects of dietary protein sources on egg performance and egg quality of Jinghong laying hens at peak production.[Method]Two hundred and eighty-eight Jinghong laying hens aged 32 weeks with similar egg production were randomly divided into 4 groups with 6 replicates per group and 12 hens per replicate. Hens in group Ⅰ (control group) were fed soybean meal (SBM) protein, hens in group Ⅱ were fed degossypolized cottonseed protein (DCP), hens in groupⅢwere fed double-zero rapeseed meal (DRM) protein, and hens in groupⅣwere fed 4%yellow mealworms (YM) and soybean meal (SBM) protein. All diets were isocaloric (11.11 Mcal·kg-1), isonitrogenous (CP, 16.5%) and had the similar standard ileum digestible AA model. The experiment lasted for 8 weeks. [Result] (1) In the whole feeding period,no significant differences were found on average egg production, egg weight and cracked eggs ratio among all groups (P>0.05). In DCP group, egg mass during 1-8w was lower than that SBM group or 4%YM group (P0.05). (2) No significant differences in the plasma aspartate transaminase (AST) among all groups were observed (P>0.05). Compared to SBM group, plasma alanine transaminase (ALT) in laying hens

  8. Coarse-grain modelling of protein-protein interactions

    NARCIS (Netherlands)

    Baaden, Marc; Marrink, Siewert J.

    2013-01-01

    Here, we review recent advances towards the modelling of protein-protein interactions (PPI) at the coarse-grained (CG) level, a technique that is now widely used to understand protein affinity, aggregation and self-assembly behaviour. PPI models of soluble proteins and membrane proteins are separate

  9. [Food value of spiruline algae for the laying hen].

    Science.gov (United States)

    Blum, J C; Guillaumin, S; Calet, C

    1975-01-01

    The three diets (composition in table I) were isonitrogenous (16,4 p. 100 crude protein), similar in their content of lysine and sulfur amino acids, but with different levels of spiruline algae : 0 (control); 7.5 or 15 p. 100. Each diet was used for the feeding of 48 hybrid pullets of medium size during a 24-week test period (32 to 56 weeks). Egg production (table II) was slightly better (47.1 g/hen/day) with 7.5 p. 100 of spirulines, compared to the control (45.3 g/hen/day), the difference being significant (P less than 0.01). With 15 p. 100 of spirulines egg production was similar to that observed in the control, but the average egg weight was reduced (58.5 vs 60.5 g) as a result of a lower albumen content. The colour of the egg yolk (table IV) was very light in the controls, but was a deep orange (above the maximum in the Roch scale) with 7.5 or 15 p. 100 of spirulines in the laying hen diet. The diet consumption, feed conversion and live weight variations (table III) show that the energy level is no higher in laying hens (about 2 500 kcal M.E./kg spirulines) than in the broiler.

  10. THE PERFORMANCE OF LAYING HENS FED DIFFERENT CALCIUM SOURCE

    Directory of Open Access Journals (Sweden)

    S. Kismiati

    2012-12-01

    Full Text Available The research was aimed to evaluate the performance of laying hens fed different calcium sources. Two hundreds of Isa Brown laying hens were used in this study. The hens were raised in individual battery cages units for 12 weeks. Four calcium source (limestone as a control, 5% limestone + 2.5% eggshells waste, 2.5% limestone + 5% eggshells waste and 7.5% eggshell waste were used in feed experiment. A completely randomized design was applied, with 4 treatments and 5 replications. Each experimental unit consisted of 10 laying hens. The parameters measured were feed intake, protein intake, calcium intake, phosphorus intake, egg production, egg weight and feed conversion ratio. Results of the research showed that the calcium source had significantly effect on performance productions. The use of eggshell waste 7.5% significantly increased the feed intake, calcium intake, phosphorus intake, egg production and egg weight except for feed conversion ratio. The conclusion of this research was that the use of eggshell waste as calcium source of feed resulted in better performance than using limestone or mixed limestone with eggshell waste.

  11. Technological and Economic Risk Analysis of laying hen breeding applying simulation

    OpenAIRE

    Kovacs, Sandor; Ertsey, Imre; Balogh, Peter

    2007-01-01

    In order to analyse risks and to choose from different decision-making strategies simulation models are often applied in several areas of animal breeding. We developed an improved Monte Carlo model for analysing laying hen breeding combined with Bayes statistics. On the basis of data from a company breeding broiler parents, our paper examines the technological and economic risks of breeding a laying-hen stock with a simulation program developed by our team. During modelling we take individual...

  12. Short chain nitrocompounds as a treatment of layer hen manure and litter; effects on in vitro survivability of Salmonella, generic E. coli, and nitrogen metabolism

    Science.gov (United States)

    Layer hen manure and litter contain appreciable amounts of uric acid, which makes these good crude protein sources for ruminants. Rumen microbial populations can upgrade the nitrogen in uric acid into high quality microbial protein of nutritional value to the host. Layer hen manure and litter can ...

  13. ISOLATION AND PURIFICATION OF LYSOZYME FROM THE HEN EGG WHITE

    Directory of Open Access Journals (Sweden)

    S. S.

    2015-12-01

    Full Text Available The aim of the research was the development of the method of lysozyme isolation from hen egg proteins. Lysozyme was isolated by differential heat denaturation of proteins with changing of the medium pH value, followed by neutralization, dialysis and additional purification by gel chromatography on Sephadex G-50. Activity was determined by bacteriolytic method (with Micrococcus lysodeikticus 4698 as a substrate. The enzyme purity and molecular mass were determined using SDS-electrophoresis and massspectrometry. The method of lysozyme isolation from hen egg proteins with the enzyme yield of 3.2 ± 0.2% and bacteriolytic activity of 22 025 ± 1 500 U/mg is modified. According to electrophoresis data, the isolated enzyme is characterized by high degree of purity (~95–98% and is comparable with lysozyme of AppliChem company by main physical and chemical characteristics. The obtaining product is stored in a crystalline form at low temperature (–24 оC for 9 months. The proposed method allows obtaining active and stable lysozyme with high purity from hen egg protein in laboratory conditions for the usage in biotechnology.

  14. 高能量低蛋白质日粮中添加生物素对蛋鸡脂类代谢的影响%Effect of high-energy low-protein diet supplemented with biotin on fat metabolism of laying hens

    Institute of Scientific and Technical Information of China (English)

    郭小权; 曹华斌; 胡国良; 张彩英; 李浩棠; 曹洪峰; 黄爱民; 罗军荣; 李麟

    2012-01-01

    The experiment was conducted to investigate the influence of biotin on fat metabolism and fatty liver hemorrhagic syndrome(FLHS) in laying hens.One hundred and thirty five healthy birds(Hy-line Variety Brown laying hens,Gallus domesticus) aged 300 days were randomly allotted into 3 dietary treatments of 45 broilers each.The groups were:1) group 1(control,semisynthetic commercial layer standard diet in accordance with the nutrient requirements of poultry(National Research Councile,1998));2) group 2(high energy-low protein diet which were partially formulated in accordance with controls;3) group 3(the high energy-low protein diet supplemented with 0.3 mg biotin/kg DM).All birds were reared for 60 days.Nine hens from each group were selected to collecte samples including serum and liver on 1,30,60 day,respectively.The serum indexs relevant to fat metabolism in serum and/or liver were investigated.The results as follows:as compared to the control,laying performance and HDL-C on the 30th and 60th day in the group 2 decreased.TG,TC,LDL-C,ALT,AST in serum and the ratio of liver fat and abdominal fat increased.Laying performance,HDL-C,TG,TC,LDL-C,ALT,AST in serum and the ratio of liver fat and abdominal fat in the group 3 on the 30th day have no difference.Laying performance and HDL-C on the 60th day in the group 3 decreased.TG,TC,LDL-C,ALT,AST in serum and the ratio of liver fat and abdominal fat increased.As compared to group 2,laying performance and HDL-C on the 30th and 60th day in the group 3 decreased.TG,TC,LDLC,ALT,AST in serum and the ratio of liver fat and abdominal fat increased.The results suggested that high energy-low protein diet can be used for the pathology model building of FLHS.The high energy-low protein diet supplemented with 0.3 mg biotin/kg DM may affect fat metabolism in laying hen and prevent FLHS.%选用300日龄健康海蓝褐蛋鸡90羽,随机分为对照组、病理组、防治组3组(每组3

  15. Kinetics of fibrilar aggregation of food proteins

    NARCIS (Netherlands)

    Arnaudov, L.N.

    2005-01-01

    In this thesis we study the kinetics of fibrilar aggregation of two model proteins widely used in the food industry -b-lactoglobulin (b-lg) and hen eg

  16. Kinetics of fibrilar aggregation of food proteins

    NARCIS (Netherlands)

    Arnaudov, L.N.

    2005-01-01

    In this thesis we study the kinetics of fibrilar aggregation of two model proteins widely used in the food industry -b-lactoglobulin (b-lg) and hen

  17. Laying hen performance in different production systems; why do they differ and how to close the gap? Results of discussions with groups of farmers in The Netherlands, Switzerland and France, benchmarking and model calculations

    NARCIS (Netherlands)

    Leenstra, F.R.; Maurer, V.; Galea, F.; Bestman, M.W.P.; Amsler, Z.; Visscher, J.; Vermeij, I.; Krimpen, van M.M.

    2014-01-01

    Free range and organic systems expose the laying hen more to unexpected events and adverse climatic conditions than barn and cage systems. In France, The Netherlands and Switzerland the requirements for a hen suitable to produce in free range and organic systems were discussed with farmers. The

  18. Effect of Excess Dietary Methionine on the Performance of Laying Hens of Various Live Body Weight

    Directory of Open Access Journals (Sweden)

    Şahin Çadırcı

    2015-02-01

    Full Text Available An experiment was conducted with laying hens to determine the effects of feeding excesses of methionine in a practical layer diet. One hundred and thirty two laying hens at 61 weeks of age were used for the experiment. Two body weight groups (light and heavy and three levels of mehionine were assigned to six groups of laying hen in a 2x3 factorial design. The diets were a 16.5% crude protein corn and soybean meal positive control diet (0.33% methionine, and this diet fortified with 1.00% additional DL-Methionine or 1.50% additional DL-Methionine. The diets were fed ad libitum to the hens for 10 consecutive weeks of production. For the total production period, body weight gain, hen-day egg production, egg weight, egg mass, daily feed intake and feed conversion ratio were not significantly different among any of the treatments in the two body weight groups (P>0.05. The study indicated that considerable tolerance exists in laying hens for individual excesses of the DL-Methionine commonly used as supplement in poultry diets.

  19. Factors Affecting Profitability of Layer Hens Enterprises

    Directory of Open Access Journals (Sweden)

    Ebraheem Altahat

    2012-01-01

    Full Text Available Problem statement: Layer hen enterprises suffer from low profitability or losses in many of developing countries all over the world. Jordan is not an acceptance. Approach: This study aimed at investigating the influence of ten main factors affecting the profitability of layer hen producers. The investigated factors include price of purchased pullet, feed price, cost of labor, cost of veterinary service and medicine, building and machinery depreciation, repairs and maintenance and miscellaneous costs, length of production cycle, feed conversion ratio, mortality rate, egg sale price and laying percentage. Results: The study used a multiple regression profit model to estimate the effect of the above mentioned factors on profit per kg egg produced. The direction and quantity of relationship between profit per kg egg and variables affecting profit were investigated. Data from 40 operating and randomly selected egg production enterprises in the country was collected. Data was obtained directly from the producers during April to mid August 2010. Semi structured interviews were conducted with a pre-tested questionnaire. The data obtained via interview surveys were processed to calculate profit per kg egg and other relevant information for inclusion in a profit function model. Fifteen eggs are registered to be 1 kg in the study. Cost and income items used to calculate profit in the study. The results of the study revealed that the feed price was found to be the factor which has the highest negative impact on the profitability showing the coefficient-3.01. The egg sale price was with high positive impact on profitability showing the coefficient 2.633. Conclusion/Recommendations: From the results of the study it could be concluded that higher prices of purchased or breeding pullet, higher feed price, higher cost of labor, higher cost of veterinary service and medicine, higher other costs including building and machinery depreciation, repairs and

  20. The effect of dietary protein and lysine on egg quality and production of laying hens during 28-42 weeks of age

    Directory of Open Access Journals (Sweden)

    Hasan Mohammadi Emarat

    2015-04-01

    Full Text Available An experiment was conducted to evaluate the effect of dietary crude protein and lysine levels on quality and quantity of egg production. Fifteen diets consisted of 3 levels of protein (14, 15 and 16% and 5 levels of lysine (0.71, 0.74, 0.77, 0.80 and 0.83 % in a 35 factorial arrangement were provided. Each diet was randomly fed to 4 replicates of 12 birds, during four periods of 4 weeks (28-44wks of age. Egg number and mortality was recorded daily, whereas feed consumption determined for each period. Eggs from each replicate were weighed at the end of three consecutive days of each period and six eggs were used to measure the egg quality characteristics. Although the feed intake did not affected by dietary protein but the egg production, egg mass and feed conversion were improved significantly (p

  1. Changes in the protein secondary structure of hen's egg yolk determined by Fourier transform infrared spectroscopy during the first eight days of incubation.

    Science.gov (United States)

    Lilienthal, Sabrina; Drotleff, Astrid M; Ternes, Waldemar

    2015-01-01

    In this study, incubation-induced alterations in the protein secondary structures of egg yolk and its major fractions (granules, plasma, and low-density lipoproteins [LDL]) were monitored during the first 8 d of embryogenesis using Fourier transform infrared spectroscopy (FTIR) and isoelectric focusing (IEF). Two factors potentially connected with egg yolk protein secondary structure changes were evaluated, i.e., the pH value of incubated egg yolk, and phosvitin, an important egg yolk protein assumed to play an important role in hematopoiesis as the iron carrier during early embryogenesis. However, neither the significant increase in pH value (6.07 to 6.92) of egg yolk during incubation of fertilized eggs, nor the release of iron from phosvitin were found to be directly related to the changes in protein secondary structure in egg yolk and its fractions. FTIR showed that the protein conformation in whole egg yolk, granules, and LDL was stable during incubation, but separate evaluation of the plasma fraction revealed considerable changes in secondary structure. However, it is unlikely that these changes were provoked by structure changes of the proteins originally present in plasma; instead, the physiological influx of albumen into the yolk sac was expected to play an important role in the protein modifications of egg yolk, as was shown both by FTIR and IEF of the water-soluble egg yolk proteins. Moreover, FTIR was used to determine the naturally occurring proportions (%) of the secondary structure elements in egg yolk and its 3 fractions on d 0 of incubation. The granules fraction mainly consisted of a mixture of inter- and intramolecular β-sheets (57.04%±0.39%). The plasma fraction was found to consist mainly of α-helices (43.23%±0.27%), whereas LDL was composed almost exclusively of intramolecular β-sheets (67.36%±0.56%) or β-turns, or both. On the other hand, whole egg yolk was mainly composed of intermolecular β-sheets (39.77%±0.48%), potentially

  2. Late evening artificial insemination of turkey hens.

    Science.gov (United States)

    Nestor, K E; Renner, P A

    1982-12-01

    Turkey hens were artificially inseminated at three times (0800, 1100, or 2200 hr) under conditions where high or low fertility would be expected. Four trials were conducted and the same two persons collected semen and inseminated the hens in all trials. Each hen was inseminated with .025 cc undiluted semen. There was no significant difference in fertility when hens were inseminated at different times of the day in the first three trials. In a fourth trial, where high fertility was expected, hens inseminated at 0800 hr had lower fertility than those inseminated at 2200 hr. There was no significant difference between inseminating at 0800 or 1100 hr and 1100 or 2200 hr. The results of this study indicate that late evening insemination is not necessary for high fertility.

  3. THE STUDY OF THE ECONOMIC EFFICIENCY IN AMINO-ACIDS SUPPLEMENTATION OF THE LAYING HEN`S FODDER

    Directory of Open Access Journals (Sweden)

    ELIZA SIMIZ

    2013-12-01

    Full Text Available The experiment has been carried out on 69 Tetra SL hens, 27-36 weeks old, distributed into 3 groups consisted of 23 hens. They were fed with fodder recipes with different protein levels (17, 16 and respectively 15%. These recipes have been supplemented with DL-methionine and L-lysine up to the level of 0.80% lysine and 0.38% methionine. Fish flour has participated in a proportion of 3% in group 1, 1.5% in group 2 and it was absent from the fodder structure used in group 3. The reduction of crude protein with 1-2p% compared to the available commercial products, but with an amino acid supplementation, has led to the improvement of the economic criteria regarding egg production, generating savings of 7.7% in the group with 16% CP and of 12.8% in the group with 15% CP. The egg mass has not been affected significantly (p>0.05, the best yield being achieved from the hens fed with a 16%CP recipe.

  4. Prevalence and magnitude of helminth infections in organic laying hens (Gallus gallus domesticus) across Europe.

    Science.gov (United States)

    Thapa, Sundar; Hinrichsen, Lena K; Brenninkmeyer, Christine; Gunnarsson, Stefan; Heerkens, Jasper L T; Verwer, Cynthia; Niebuhr, Knut; Willett, Alice; Grilli, Guido; Thamsborg, Stig M; Sørensen, Jan T; Mejer, Helena

    2015-11-30

    Helminths are associated with health- and welfare problems in organic laying hens. The present observational cross-sectional study therefore aimed to estimate the prevalence and worm burdens of intestinal helminths in organic flocks of laying hens in 8 European countries, and to identify management factors that might be associated with helminth infections, with emphasis on Ascaridia galli. Data on flock-level management factors (e.g. nutritional factors, litter quality, housing system, opening- and closing hours of popholes, pasture rotation and provision of occupational materials) were collected during a farm visit when the hens were on average 62 weeks old. Worm counts were performed for 892 hens from 55 flocks and the number of ascarid (presumably primarily A. galli) eggs per g faeces (EPG) for 881 hens from 54 flocks. The association between parasitological parameters (prevalence, worm burden and EPG) and the management factors were analysed by multivariate models. Results showed that A. galli was highly prevalent across Europe with an overall mean prevalence of 69.5% and mean worm burden of 10 worms per hen. The overall mean prevalence and worm burden for Heterakis spp. were 29.0% and 16 worms per hen, respectively, with a large variation between countries. On average, the hens excreted 576 ascarid EPG. The mean prevalence of Raillietina spp. was 13.6%. A positive correlation was found between mean A. galli worm burden and ascarid EPG. Of the analysed management factors, only pasture access time had a significant negative association with A. galli worm burden which was in contrast to the general belief that outdoor access may increase the risk of helminth infections in production animals. In conclusion, the complexity of on-farm transmission dynamics is thus a challenge when evaluating the relative importance of management factors in relation to helminth infections.

  5. Gamma radiation effect on allergen protein of laying hen eggs;Efeito da radiacao gama em proteina alergenica de ovos de galinhas poedeiras

    Energy Technology Data Exchange (ETDEWEB)

    Harder, Marcia Nalesso Costa

    2009-07-01

    The egg is the most complete natural food; it has all the necessary nutrients such as vitamins, aminoacids and essential minerals to maintain a life. However, although, has several proteins that promote allergies in considerable part of the world population. To determine allergenic food proteins, one of the most used tests is the immunoassays such as ELISA (enzyme linked immunosorbent assay), where the antibody recognizes the antigen and this connection is showed by an enzymatic system, in other words, optical density. The aim of this study was to determine the polyclonal antibody efficiency, produced in laboratory, to identify the presence the ovo mucoid antigen in treated eggs by gamma irradiation for its inactivation. To evaluate the treatments, polyclonal antibody was produced in four New Zealand female rabbits, at 45 days old, immunized with bio conjugated ovo mucoid. Was used Freund Complete Adjuvant at first immunization and PBS Buffer at four subsequently immunizations every fifteen days, plus a booster 48 hours before the blood retreated. The blood serum was tittered by PTA ELISA (Plate trapped antigen). All procedures were approved by Institute of Animal Science and Pastures (IZ)'s Committee of Ethical and Animal Experimentation and preceded according to European Norms for ethical and animal welfare. It was used, in nature, commercial laying eggs, from the Genetic Department of Agricultural University Luiz de Queiroz ESALQ/USP. So the samples were submitted to the gamma radiation coming from a source of {sup 60}Co, type Multipurpose at the Energetically Researches and Nuclear Institute (IPEN), under a dose rate of 19.4 and 31.8Gy/hour, in the doses: 0 (control); 10KGy; 20KGy and 30KGy, in all rates. By the ELISA s test we can find the egg allergen ovo mucoid and the radiation treatment do not showed considerable changes. So we can concluded that the antibody produced is capable of identify the ovo mucoid allergenic protein and the gamma irradiation

  6. Computational modeling of membrane proteins.

    Science.gov (United States)

    Koehler Leman, Julia; Ulmschneider, Martin B; Gray, Jeffrey J

    2015-01-01

    The determination of membrane protein (MP) structures has always trailed that of soluble proteins due to difficulties in their overexpression, reconstitution into membrane mimetics, and subsequent structure determination. The percentage of MP structures in the protein databank (PDB) has been at a constant 1-2% for the last decade. In contrast, over half of all drugs target MPs, only highlighting how little we understand about drug-specific effects in the human body. To reduce this gap, researchers have attempted to predict structural features of MPs even before the first structure was experimentally elucidated. In this review, we present current computational methods to predict MP structure, starting with secondary structure prediction, prediction of trans-membrane spans, and topology. Even though these methods generate reliable predictions, challenges such as predicting kinks or precise beginnings and ends of secondary structure elements are still waiting to be addressed. We describe recent developments in the prediction of 3D structures of both α-helical MPs as well as β-barrels using comparative modeling techniques, de novo methods, and molecular dynamics (MD) simulations. The increase of MP structures has (1) facilitated comparative modeling due to availability of more and better templates, and (2) improved the statistics for knowledge-based scoring functions. Moreover, de novo methods have benefited from the use of correlated mutations as restraints. Finally, we outline current advances that will likely shape the field in the forthcoming decade.

  7. Infectious Bronchitis Vaccination Protocols for Laying Hens

    Directory of Open Access Journals (Sweden)

    A. Sulaiman

    2011-12-01

    Full Text Available A research was conducted to investigate the effects of vaccination protocols for Infectious Bronchitis (IB on egg production, egg quality, and IB antibody titres of laying hens. Different initial vaccination (Control, VicS eye, VicS spray, VicS water, A3 eye, A3 spray, and A3 water for IB were administered to day-old Isa Brown hens. Half the hens were revaccinated regularly during lay whereas the other hens were not vaccinated. Results showed that initial vaccination treatment had significant effects on hen day egg production and egg quality of egg weight, shell reflectivity, shell breaking strength, shell thickness, albumen height, Haugh Units, and IB antibody titre levels, but had no effect on percentage of shell and yolk colour. Egg weight and shell reflectivity were less favourable in the control hens. In contrast, shell breaking strength and shell thickness were highest for the group that initially received A3 vaccine in water. However, regular revaccination had some deleterious effects on egg production and egg quality. There were no significant effects of revaccination on IB antibody titres. It is concluded that there was little advantage in regularly revaccinating laying hens for IB virus, since they had received appropriate initial vaccination.

  8. CASHEW NUT MEAL IN THE FEEDING OF BROWN LAYING HENS

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Braga Cruz

    2015-02-01

    Full Text Available The use of alternative foods to replace conventional foods is becoming a source of research for many researchers. The cashew nut meal (CNM has high energy and protein value, may be a partial substitute for corn and soybean meal for poultry feed. In this context, this research was conducted to evaluate the effect of inclusion of CNM on the utilization of nutrients in the ration for laying hens, as well as the performance and characteristics of the eggs. The study used 180 Dekalb Brown laying hens 27 weeks of age, distributed in a completely randomized design with six treatments and five replicates of six birds. Treatments consisted of a control diet without CNM and others with the inclusion of this food at levels of 5, 10, 15, 20 and 25%. Upon regression analysis, a linear increase in nitrogen metabolism, crude energy and apparently metabolizable energy was seen. The dry matter digestibility and metabolizable energy corrected for rations were not affected by the inclusion of the CNM. Feed intake and egg weight were not affected by the inclusion of the CNM; however, egg production, egg mass, feed conversion, and yolk color worsened linearly with inclusion of CNM. Compared to control diet, the inclusion of CNM worsened the egg mass and feed conversion from 15%, and yolk color from 20%. As a result, it is recommended the inclusion of the CNM in the diet of laying hens at a maximum level of 10%.

  9. A highly amyloidogenic region of hen lysozyme.

    Science.gov (United States)

    Frare, Erica; Polverino De Laureto, Patrizia; Zurdo, Jesús; Dobson, Christopher M; Fontana, Angelo

    2004-07-23

    Amyloid fibrils obtained after incubating hen egg-white lysozyme (HEWL) at pH 2.0 and 65 degrees C for extended periods of time have been found to consist predominantly of fragments of the protein corresponding to residues 49-100, 49-101, 53-100 and 53-101, derived largely from the partial acid hydrolysis of Asp-X peptide bonds. These internal fragments of HEWL encompass part of the beta-domain and all the residues forming the C-helix in the native protein, and contain two internal disulfide bridges Cys64-Cys80 and Cys76-Cys94. The complementary protein fragments, including helices A, B and D of the native protein, are not significantly incorporated into the network of fibrils, but remain largely soluble, in agreement with their predicted lower propensities to aggregate. Further analysis of the properties of different regions of HEWL to form amyloid fibrils was carried out by studying fragments produced by limited proteolysis of the protein by pepsin. Here, we show that only fragment 57-107, but not fragment 1-38/108-129, is able to generate well-defined amyloid fibrils under the conditions used. This finding is of particular importance, as the beta-domain and C-helix of the highly homologous human lysozyme have been shown to unfold locally in the amyloidogenic variant D67H, which is associated with the familial cases of systemic amyloidosis linked to lysozyme deposition. The identification of the highly amyloidogenic character of this region of the polypeptide chain provides strong support for the involvement of partially unfolded species in the initiation of the aggregation events that lead to amyloid deposition in clinical disease.

  10. Antidote to Controversy? Responses to Carolyn Henly.

    Science.gov (United States)

    Randall, Mary Ella; And Others

    1993-01-01

    Provides four practicing teachers' written responses to Carolyn Henly's article entitled "Reader Response Theory as Antidote to Controversy: Teaching "The Bluest Eye," which appears in the same issue. (HB)

  11. 'As I told Henning the other day'

    DEFF Research Database (Denmark)

    Andersen, Nina Møller

    2008-01-01

    En analyse af sætningen 'Som jeg også sagde til Henning forleden dag' ud fra henholdsvis en klassisk argumentationsanalytisk synsvinkel, en sproghandlingsanalytisk synsvinkel og en dialogisk sysnvinkel (BAchtin)...

  12. Níveis de proteína e de vitamina E para matrizes de frango de corte. 1. Efeito sobre o desempenho das matrizes, composição do ovo e desempenho da progênie Protein and vitamin E levels for broiler breed hens. 1. Effects on broiler breed performance, egg composition and performance of their progeny

    Directory of Open Access Journals (Sweden)

    S.L.T. Barreto

    1999-04-01

    Full Text Available Avaliou-se o efeito da suplementação de dois níveis de proteína bruta (PB, 14 e 16%, e dois de vitamina E (VE, 25 e 250mg/kg, na dieta sobre o desempenho e composição do ovo de matrizes de frangos de corte, entre 24 e 54 semanas de idade e sobre o desempenho de suas progênies. Foram alojadas 480 fêmeas e 48 machos da linhagem Ross, com 18 semanas de idade, em 16 boxes com 30 fêmeas e 3 machos em cada um. As dietas foram à base de milho e farelo de soja, sendo todas isocalóricas (2750kcal de EM/kg. O delineamento experimental foi o inteiramente ao acaso, constituído de quatro tratamentos em esquema fatorial 2×2, sendo dois níveis de PB (NPB e dois níveis de VE (NVE, representados por quatro repetições cada um. A produção de ovos/ave/dia, o número de ovos/ave-alojada, o peso do ovo, a viabilidade, o peso corporal das fêmeas no final do experimento e a percentagem de gema no ovo não foram influenciados (P>0,05 pelos tratamentos e nem pela interação entre NVE × NPB. Menor percentagem de casca (P0,05 dos NPB e dos NVE, representados pelo peso do ovo incubado, pela taxa de eclosão, pela razão entre o peso do ovo e o peso da progênie e pelo desempenho da progênie até a idade de abate. Porém, maior peso ao nascer (PThis study was carried out with the objective of evaluating the effects of supplementation of two levels of crude protein (14 and 16% CP and vitamin E (25 and 250mg VE/kg in the diet on the performance and egg composition of broiler breed hens and on the performance of their progeny during the laying period (24-to-54 weeks of age. Thus 480 female and 48 male Ross breeder 18-week-old birds were randomly distributed in 16 floor pens, with 30 females and three males in each one. The diets were based on corn and soybean meal, and all them were isoenergetics (2750kcal ME/kg. The experimental design was a complete randomized block and the treatments were arranged in 2 × 2 factorial (CP × VE levels with two

  13. Adding value to the meat of spent laying hens manufacturing sausages with a healthy appeal

    Directory of Open Access Journals (Sweden)

    KMR de Souza

    2011-03-01

    Full Text Available The aim of this study was to evaluate the viability of the use of spent laying hens' meat in the manufacturing of mortadella-type sausages with healthy appeal by using vegetable oil instead of animal fat. 120 Hy-line® layer hens were distributed in a completely randomized design into two treatments of six replicates with ten birds each. The treatments were birds from light Hy-line® W36 and semi-heavy Hy-line® Brown lines. Cold carcass, wing, breast and leg fillets yields were determined. Dry matter, protein, and lipid contents were determined in breast and leg fillets. The breast and legg fillets of three replicates per treatment were used to manufacture mortadella. After processing, sausages were evaluated for proximal composition, objective color, microbiological parameters, fatty acid profile and sensory acceptance. The meat of light and semi-heavy spent hens presented good yield and composition, allowing it to be used as raw material for the manufacture of processed products. Mortadellas were safe from microbiological point of view, and those made with semi-heavy hens fillets were redder and better accepted by consumers. Values for all sensory attributes were evaluated over score 5 (neither liked nor disliked. Both products presented high polyunsaturated fatty acid contents and good polyunsaturated to saturated fatty acid ratio. The excellent potential for the use of meat from spent layer hens of both varieties in the manufacturing of healthier mortadella-type sausage was demonstrated.

  14. Digestible threonine to lysine ratio in diets for laying hens aged 24-40 weeks

    Directory of Open Access Journals (Sweden)

    Tatiana Cristina da Rocha

    2013-12-01

    Full Text Available Two-hundred sixteen white laying hens were used to assess the ideal ratio of digestible threonine:lysine in diets for laying hens at 24 to 40 weeks of age. Birds were assigned to a randomized block design, with six treatments, six replicates per treatment and six birds per experimental unit. The cage was used as the blocking criterion. Experimental diets contained different digestible threonine:digestible lysine ratios (65, 70, 75, 80, 85 and 90% with 142 g/kg of crude protein. Experimental diets were formulated to be isonitrogenous and isocaloric with different contents of L-glutamic acid. Feed intake (g/hen/d, egg production (%, egg weight (g, egg mass (g/hen/d, feed conversion ratio (kg/dozen and kg/kg egg, eggshell weight (g, albumen weight (g, yolk weight (g and body weight gain (g were assessed. The maximum egg production was observed at 78% digestible threonine:digestible lysine ratio, while the best values of feed conversion ratio (kg/dozen egg and feed conversion ratio (kg/kg of egg were observed at 77.6% and 75%, respectively. Feed intake, egg mass and egg contents (yolk, albumen and eggshell were not affected by treatments. The estimated digestible threonine:digestible lysine ratio of Hy-Line W36 laying hens at 24 to 40 weeks of age is 78%, corresponding to 5.70 g/kg of dietary digestible threonine.

  15. 基于Petri网的母鸡转舍业务流程建模优化研究%Research on Modeling and Optimizing Business Process of Hen Transfer Based on Petri Nets

    Institute of Scientific and Technical Information of China (English)

    李兴国; 刘倩茹

    2013-01-01

    选择农牧养殖业中的母鸡转舍这一业务流程建立Petri网模型,并对模型进行分析计算,找出时间瓶颈,依据ECRS原则提出优化方案,利用流程周期时间指标评价优化前后流程的效率,比较表明该模型在农牧养殖业务流程优化中是非常有效的.%The paper chose the business process of transferring hens from barton to henhouse in agriculture and animal husbandry breeding to model Petri nets and found time bottleneck by analyzing and calculating the model. According to principle ECRS proposed optimized scheme and evaluated the processes' efficiency of before and after optimization using the time index of process cycle. The result shows that the model is very effective in process optimization of the agriculture and animal husbandry breeding.

  16. [Discussion of actual legal minimum requirements for feeder space and perch length in laying hen husbandry in the light of the body widths measured in Lohmann Selected Leghorn and Lohmann Brown laying hens].

    Science.gov (United States)

    Briese, Andreas; Spindler, Birgit

    2013-01-01

    Legal requirements on space and dimensions regarding furnished cages and alternative systems in laying hen husbandry are subject of constant discussion. Further knowledge about basic measures of the hens might help to come to reasonable results in the future. Digital images of Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB) laying hens, housed at the Lehr- und Forschungsgut Ruthe, University for Veterinary Medicine Hanover, Foundation, in Big Dutchman Eurovent laying hen cages, were made at three stages (19th, 36th and 58th week) of production. All hens had been taken out of their cages by night and set on a perch in a special cage used to photograph the hens frontally under controlled conditions. Body widths were calculated by a python application Cdisto.py0 2009 Andreas Briese) to mark and measure the body width in the digital images of a total of 156 hens. Mean body widths of 133.77 mm in Lohmann-LSL hens (SD = 9.71; N = 64; mean weight: 1.73 kg) and of 152.55 mm in Lohmann-LB hens (SD = 10.31; N = 92; mean weight: 1.93 kg) respectively were found. Even slight changes in body weights had no effect on the body width. Nonetheless the differences between both hybrids were always statistically significant (Mann-Whitney p < 0,001). Using these preliminary results on body width in a mathematical model simultanious feeding behaviour becomes only possible if the number of animals is reduced by 10.3% to 89.7% in LSL and by 21.3% to 78.7% in LB breeds in relation to a calculated maximum on base of the minimum space requirements for furnished cages in the EU-Dir 74/1999/EC.

  17. CASHEW NUT MEAL IN THE FEEDING OF BROWN LAYING HENS

    OpenAIRE

    Carlos Eduardo Braga Cruz; Ednardo Rodrigues Freitas; Regina Patrícia de Souza Xavier; Danilo Rodrigues Fernandes; Germano Augusto Gerônimo Nascimento; Pedro Henrique Watanabe

    2015-01-01

    The use of alternative foods to replace conventional foods is becoming a source of research for many researchers. The cashew nut meal (CNM) has high energy and protein value, may be a partial substitute for corn and soybean meal for poultry feed. In this context, this research was conducted to evaluate the effect of inclusion of CNM on the utilization of nutrients in the ration for laying hens, as well as the performance and characteristics of the eggs. The study used 180 Dekalb Brown laying ...

  18. Standardized Ileal Amino Acid Digestibility of Corn, Corn Distillers' Dried Grains with Solubles, Wheat Middlings, and Bakery By-Products in Broilers and Laying Hens.

    Science.gov (United States)

    Adedokun, S A; Jaynes, P; Payne, R L; Applegate, T J

    2015-10-01

    Standardized ileal amino acid digestibility (SIAAD) of 5 samples of corn distillers dried grain with solubles (DDGS), 5 samples of bakery by-products (BBP), 3 samples of corn, and 1 sample of wheat middlings (WM) were evaluated in broilers and laying hens. Diets containing each of the 14 feed ingredients were evaluated in 21 day-old broiler chickens. The DDGS and BBP containing diets were fed to 30-week-old laying hens, while corn and wheat middling were evaluated in 50-week-old laying hens. All the diets were semi-purified with each feed ingredient being the only source of amino acid (AA). To obtain SIAAD values, apparent ileal AA digestibility was corrected for basal ileal endogenous AA losses using values generated from broilers and laying hens fed a nitrogen-free diet. Ileal crude protein digestibility for the 5 DDGS samples was higher (P hens. Broilers had higher SIAAD for DDGS 2, 3, 4, and 5 while there was no difference for DDGS 1 except for 4 AA where broilers had higher (P hens, and SIAAD values for the 16 AA (9 indispensable and 7 dispensable) evaluated in this study were higher (P hens was observed for WM. Results from this study confirm that high variability in digestibility exists between different samples of DDGS. Differences in SIAAD between broilers and laying hens were observed in some samples of DDGS and BBP.

  19. Hypermethylation and post-transcriptional regulation of DNA methyltransferases in the ovarian carcinomas of the laying hen.

    Science.gov (United States)

    Lee, Jin-Young; Jeong, Wooyoung; Lim, Whasun; Lim, Chul-Hong; Bae, Seung-Min; Kim, Jinyoung; Bazer, Fuller W; Song, Gwonhwa

    2013-01-01

    DNA methyltransferases (DNMTs) are key regulators of DNA methylation and have crucial roles in carcinogenesis, embryogenesis and epigenetic modification. In general, DNMT1 has enzymatic activity affecting maintenance of DNA methylation, whereas DNMT3A and DNMT3B are involved in de novo methylation events. Although DNMT genes are well known in mammals including humans and mice, they are not well studied in avian species, especially the laying hen which is recognized as an excellent animal model for research on human ovarian carcinogenesis. Results of the present study demonstrated that expression of DNMT1, DNMT3A and DNMT3B genes was significantly increased, particularly in the glandular epithelia (GE) of cancerous ovaries, but not normal ovaries. Consistent with this result, immunoreactive 5-methylcytosine protein was predominantly abundant in nuclei of stromal and GE cells of cancerous ovaries, but it was also found that, to a lesser extent, in nuclei of stromal cells of normal ovaries. Methylation-specific PCR analysis detected hypermethylation of the promoter regions of the tumor suppressor genes in the initiation and development of chicken ovarian cancer. Further, several microRNAs, specifically miR-1741, miR-16c, and miR-222, and miR-1632 were discovered to influence expression of DNMT3A and DNMT3B, respectively, via their 3'-UTR which suggests post-transcriptional regulation of their expression in laying hens. Collectively, results of the present study demonstrated increased expression of DNMT genes in cancerous ovaries of laying hens and post-transcriptional regulation of those genes by specific microRNAs, as well as control of hypermethylation of the promoters of tumor suppressor genes.

  20. Laying performances and egg quality of local barred hens under ...

    African Journals Online (AJOL)

    SARAH

    2014-02-28

    Feb 28, 2014 ... Key words: egg quality, laying performances, local barred hens. ... nutritional status, income of many small-scale ... particular information associated with different ... hens and 1 cock per unit, house in battery cages made of.

  1. Porous concrete block as an environmental enrichment device increases activity of laying hens in cages.

    Science.gov (United States)

    Holcman, A; Gorjanc, G; Stuhec, I

    2008-09-01

    The purpose of this study was to consider the influence of simple and cheap environmental enrichment such as porous concrete on the behavior of laying hens in conventional cages. Forty brown laying hens were housed in individual wire mesh cages: 20 in experimental cages with porous concrete block provided for pecking and 20 in a control group without concrete block provided. Porous concrete block (5 cm length x 5 cm width x 5 cm height) was mounted on the side wall at the height of the hen's head. Behavior was studied from 42 to 48 wk of age. A group of 8 hens was filmed for 24 h, and the camera was moved each day so that all 40 hens were recorded over 5 d each wk. Videotaping was performed in wk 1, 3, 5, and 7 of the experiment. States (long-term behavior) were observed with 5-min interval recording (feeding, preening, resting, and remaining inactive), whereas events (short-term activities) were observed with instantaneous recording (drinking, pecking concrete, pecking neighbors, pecking cage, and attempting to escape). Data were analyzed with generalized linear mixed model with binomial distribution for states, and Poisson distribution for events. Monte Carlo Markov Chain methods were used to estimate model parameters. Because posterior distributions of quantities of interest were skewed, medians and standard errors are reported. Hens in experimental cages were more active in long-term behavior than controls (64.9 +/- 1.9 and 59.3 +/- 1.9% of the light period, respectively). Correspondingly, hens in the control group showed more long-term inactivity. In addition to pecking the porous concrete block, hens in experimental cages also showed other short-term activities with greater frequency (4.10 +/- 0.31 and 3.51 +/- 0.25 events per h, respectively). Our hypothesis that hens in enriched cages would have a greater level of activity was confirmed. Provision of a piece of porous concrete block as a pecking substrate enriched the environment of the birds at negligible

  2. Influence of gastrointestinal parasitism on biochemical variables in blood of laying hens

    Directory of Open Access Journals (Sweden)

    Josué P Topázio

    2015-11-01

    Full Text Available Objective. This study describes the influence of endoparasites and diet on biochemical variables in sera of brown laying hens. Materials and methods. Biochemical parameters (seric levels of cholesterol, triglycerides, total protein, uric acid, albumin, and alanine aminotransferase activity were assessed in blood samples of poultry. Three populations of laying hens of different properties (n=20 each represented our experimental design, from which blood (serum and feces were collected for biochemical and parasitological analyzes, respectively. Results. From 60 feces samples evaluated 49 were positive for the presence of parasites and 11 were negative. Among the positive samples, 23 had infection with Eimeria spp and the other 26 samples had mixed parasitism with Eimeria spp and Heterakis gallinarum, which influenced (increasing the levels of total protein and globulin. However, when parasites were analyzed separately, it was observed that the infection by Eimeria spp affected parameters such as cholesterol (which increased, p=0.001 and triglycerides, showing lower results than when the hen was parasitized by Eimeria spp. (p=0.01. Significant (p<0.05 difference was observed in all biochemical variables when the three diets were compared. Conclusions. Our results allowed concluding that the parasitic infection and diet in laying hens influenced the results of serum biochemical parameters evaluated. The main conclusion we found that parasitism caused an increase in total protein and globulin (ie immune response, and there was a negative correlation between parasite load and albumin, uric acid and ALT.

  3. Concentração de proteínas em gemas de ovos de poedeiras (Gallus gallus nos diferentes ciclos de postura e sua interferência na disponibilidade do ferro Protein concentration (phosvitin and lipovitelin in egg yolks of Laying Hens (Gallus gallus in different posture cycles and its interference in the iron availability

    Directory of Open Access Journals (Sweden)

    Érika Vidal Sartori

    2009-09-01

    Full Text Available O ovo é o produto de eficiente transformação biológica feita pela galinha (Gallus gallus de postura, com alta qualidade nutricional para o consumo humano. Na gema do ovo encontra-se a proteína denominada fosvitina, que atua como carreadora do ferro se ligando a ele. A deficiência de ferro ocorre normalmente devido ao consumo insuficiente de alimentos fontes de ferro ou à baixa biodisponibilidade. O objetivo da pesquisa foi verificar a concentração de proteínas, em especial a fosvitina/lipovitelina presente em gemas de ovos crus e cozidos nos diferentes ciclos de postura (inicial, intermediário e final e avaliar a interferência desta proteína na disponibilidade do micronutriente ferro. Os tratamentos foram realizados em diferentes períodos e utilizaram ovos crus e cozidos, sendo gemas cruas de poedeiras em início, meio e fim de postura e gemas cozidas nos três ciclos de postura. Foram realizadas as análises de composição centesimal, concentração de ferro total e dialisável, concentração de proteínas em gemas e eletroforese em gel de poliacrilamida (SDS-PAGE. Houve diferença na concentração de proteínas e diferentes níveis de ferro dialisável nos três ciclos de postura, porém em gemas cruas e cozidas. Com o passar dos ciclos (inicial, intermediário e final, as poedeiras mais velhas, apresentaram ovos (gemas com um teor mais elevado de ferro disponível, porém uma quantidade inferior de proteínas em especial a fosvitina/lipovitelina, comparando-se com os ciclos inicial e intermediário. A disponibilidade de ferro foi mais elevada em gemas que passaram pelo processo de cocção, porém em poedeiras de postura final.The egg is the product of efficient biological transformation made by a laying hen. It has high nutritional value for human consumption. Most of the iron in egg yolk is bound by phosvitin, a major protein present in the egg yolk. Iron deficiency normally occurs due to insufficient intake of dietary iron

  4. The effect of essential plant oils on mineral composition of egg mass and blood parameters of laying hens

    Directory of Open Access Journals (Sweden)

    Róbert HERKEĽ

    2016-12-01

    Full Text Available The aim of study was to analyze the dietary effect of pumpkin and flaxseed oils on mineral composition of egg mass and blood parameters of laying hens. At 38 weeks of age, Lohmann Brown Lite hens were housed in three-floor cages, divided into three dietary groups (C-control, E1-pumpkin oil (3%, E2-flaxseed oil (3%. There were housed six hens in one cage. A total 18 hens were monitored. In the control group hens were fed with standard complete feed mixture for laying hens and in the experimental groups by feed mixtures with supplementation of pumpkin or flaxseed oils. Vitamin E was added into feed mixture in the experimental groups. The experiment lasted 52 days. Twelve eggs from each dietary treatment were randomly selected and analyzed. As regards the mineral composition of eggs, only concentrations of calcium after both oil supplementations and zinc after flaxseed oil supplementation in diet were significantly (P0.05 influence on enzymatic and protein profile.

  5. Parthenogenesis in mated Chinese Painted quail (Coturnix chinensis) hens decreases sperm-egg penetration and alters albumen characteristics.

    Science.gov (United States)

    Santa Rosa, P; Parker, H M; Kiess, A S; McDaniel, C D

    2016-10-15

    Parthenogenesis, embryonic development without fertilization, resembles very early embryonic mortality in fertilized eggs. Also, parthenogenesis alters egg albumen characteristics in virgin Chinese Painted quail hens genetically selected for parthenogenesis (PV). When these PV hens are mated (PM), hatchability is reduced versus control mated (CM) hens that were not genetically selected for parthenogenesis. However, it is unclear if parthenogenesis, which occurs in PM hens, reduces hatchability due to infertility and altered albumen characteristics. Sperm-egg penetration (SEP) holes are indicative of true fertilization and may be useful in identifying if eggs from PM hens exhibit a decrease in fertility versus CM hens. Therefore, the objectives of this study were to determine if parthenogenesis in PM hens (1) decreases SEP, (2) alters albumen characteristics similar to parthenogenesis in eggs from PV hens, and (3) yields albumen characteristics similar to fertilized eggs containing early mortality. Daily, PV and PM eggs were collected, labeled, and incubated for 10 days, then broken out to determine the incidence of parthenogenesis and albumen characteristics. Also daily, fresh PM and CM quail eggs were macroscopically examined to determine if an egg was infertile with no embryonic development, parthenogenetic, or fertile. Each of these eggs was then microscopically examined for SEP. For both PV and PM incubated eggs, parthenogenesis decreased albumen pH, O2, and protein concentrations yet increased Ca(2+) and CO2 concentrations versus eggs with no development. For incubated PM eggs, albumen pH and O2 were lower, yet CO2 was higher for eggs containing parthenogens or early dead embryos versus infertile eggs. For SEP, fresh eggs classified as infertile or parthenogenetic from PM and CM hens had similar SEP holes but only one sixth as many SEP holes as eggs classified as fertilized. Eggs from CM hens had 3.5 times as many SEP holes as PM eggs. In conclusion

  6. Dietary Crude Protein and Metabolic Energy Requirements of Rugao Yellow Laying Hens Aged from 15 to 56 Days%15~56日龄如皋黄鸡蛋鸡粗蛋白质和代谢能的需要量

    Institute of Scientific and Technical Information of China (English)

    卢建; 曲亮; 李永峰; 沈曼曼; 李尚民; 窦套存; 胡玉萍; 王克华

    2015-01-01

    本试验旨在研究饲粮粗蛋白质( CP)和代谢能( ME)水平对15~56日龄如皋黄鸡蛋鸡生长性能和骨骼发育的影响. 试验选用14 日龄体况良好、体重( BW )接近的如皋黄鸡蛋鸡2 700只,随机分成15组,每组6个重复,每个重复30只鸡. 采用3 × 5双因子完全随机试验设计,因子1为CP水平,设17. 50%、19. 00%和20. 50% 3 个水平,因子2 为 ME 水平,设11. 11、11.51、11.92、12.34和12.78 MJ/kg 5 个水平,试验期42 d(15~56 日龄). 结果表明:1)饲粮CP、ME水平均显著影响蛋鸡35和56日龄BW( P0.05). 3)饲粮 CP 水平显著影响蛋鸡 56 日龄跖围及胫骨和股骨的长度和重量( P0.05). 由此可见,综合考虑生长性能和骨骼发育指标,如皋黄鸡蛋鸡15~56日龄饲粮适宜CP水平为19.00%,适宜ME水平为12.78 MJ/kg.%This experiment was conducted to evaluate the effects of dietary crude protein ( CP) and metabolic energy ( ME) levels on growth performance and bone development in Rugao yellow laying hens aged from 15 to 56 days. Two thousand and seven hundred 14-day-old Rugao yellow laying hens with a similar body weight were assigned to 15 groups with 6 replicates per group and 30 hens per replicate. This experiment took a 3 × 5 factorial design with 3 CP levels (17.50%, 19.00% and 20.50%) and 5 ME levels (11.11, 11.51, 11.92, 12.34 and 12.78 MJ/kg) . The trial period lasted for 42 d ( from 15 to 56 days of age) . The results showed as follows:1) the body weight at 35 and 56 days of age was significantly affected by dietary CP and ME levels (P0.05) . 3) The shank circumference and the length and weight of tibia and femur of hens at 56 days of age were significantly affected by dietary CP level (P0.05) . In conclusion, with indexes of growth performance and bone development, the appropriate dietary CP and ME levels for Rugao yellow laying hens aged from 15 to 56 days are 19. 00% and 12. 78 MJ/kg, respectively.

  7. Prevalence and magnitude of helminth infections in organic laying hens (Gallus gallus domesticus) across Europe

    DEFF Research Database (Denmark)

    Thapa, Sundar; Hinrichsen, Lena K; Brenninkmeyer, Christine

    2015-01-01

    Helminths are associated with health- and welfare problems in organic laying hens. The present observational cross-sectional study therefore aimed to estimate the prevalence and worm burdens of intestinal helminths in organic flocks of laying hens in 8 European countries, and to identify management...... and EPG) and the management factors were analysed by multivariate models. Results showed that A. galli was highly prevalent across Europe with an overall mean prevalence of 69.5% and mean worm burden of 10 worms per hen. The overall mean prevalence and worm burden for Heterakis spp. were 29.0% and 16...... access time had a significant negative association with A. galli worm burden which was in contrast to the general belief that outdoor access may increase the risk of helminth infections in production animals. In conclusion, the complexity of on-farm transmission dynamics is thus a challenge when...

  8. Information-driven structural modelling of protein-protein interactions.

    Science.gov (United States)

    Rodrigues, João P G L M; Karaca, Ezgi; Bonvin, Alexandre M J J

    2015-01-01

    Protein-protein docking aims at predicting the three-dimensional structure of a protein complex starting from the free forms of the individual partners. As assessed in the CAPRI community-wide experiment, the most successful docking algorithms combine pure laws of physics with information derived from various experimental or bioinformatics sources. Of these so-called "information-driven" approaches, HADDOCK stands out as one of the most successful representatives. In this chapter, we briefly summarize which experimental information can be used to drive the docking prediction in HADDOCK, and then focus on the docking protocol itself. We discuss and illustrate with a tutorial example a "classical" protein-protein docking prediction, as well as more recent developments for modelling multi-body systems and large conformational changes.

  9. QUALITY AND SHELF LIFE EVALUATION OF NUGGETS PREPARED FROM SPENT DUCK AND SPENT HEN MEAT

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar

    2015-12-01

    Full Text Available A study was conducted to compare the quality of nuggets prepared from spent hen and duck meat. The cooked nuggets were analyzed for pH, thiobarbituric acid (TBA, tyrosine value (TV, moisture, fat, protein, total plate count (TPC and sensory evaluations. Nuggets prepared from spent hen meat showed significantly higher (p<0.05 moisture content however pH, fat and protein content were significantly higher (p<0.05 in duck nuggets. TBA values, TVs and (TPC were highest in duck nuggets but were within the acceptable level up to 7th day of refrigerated storage (4±1°C in both types of nuggets. Both nuggets maintain their sensory quality up to 7th day of refrigeration storage but spent hen nuggets were preferred by consumers compared to nuggets prepared from spent duck meat. Result of the study indicated that, despite the comparative differences among these nuggets, spent duck and hen meat could be used for preparation of nutritionally rich and acceptable nuggets.

  10. Effects of nutritional programing on growth and metabolism caused by albumen removal in an avian model.

    Science.gov (United States)

    Willems, Els; Koppenol, Astrid; De Ketelaere, Bart; Wang, Yufeng; Franssens, Lies; Buyse, Johan; Decuypere, Eddy; Everaert, Nadia

    2015-05-01

    In mammalian models of prenatal undernutrition the maternal diet is manipulated, exerting both nutritional and hormonal effects on the offspring. In contrast, in the chicken, strictly nutritional effects can be applied. Prenatal protein undernutrition in chickens was induced by partial replacement of albumen with saline during early embryonic development (albumen-deprived group) and results were compared with a sham-manipulated and a non-manipulated group. Body weight of the albumen-deprived hens was reduced throughout the entire experimental period (0-55 weeks). The reproductive capacity was diminished in the albumen-deprived hens as reflected in the reduced number of eggs and lower egg weight. The plasma triiodothyronine levels were increased in the albumen-deprived group compared with the non-manipulated hens, but not the sham-manipulated hens. An oral glucose tolerance test (OGTT) at 10 weeks of age revealed a decreased glucose tolerance in the albumen-deprived hens. During adulthood, an age-related loss of glucose tolerance was observed in the hens, leading to disappearance of treatment differences in the OGTT. The offspring of the albumen-deprived hens (PA chicks) had reduced body weight until at least 3 weeks of age. In addition, the PA chicks had a decreased relative residual yolk weight at hatching. An insulin tolerance test revealed increased sensitivity to insulin for the PA chicks compared with the offspring of the non-manipulated (PN) and sham-manipulated hens (PS). In conclusion, prenatal protein undernutrition by albumen removal caused long-term effects on body weight, reproductive performance, and physiology. © 2015 Society for Endocrinology.

  11. Effect of Free-range Rearing on Meat Composition, Physical Properties and Sensory Evaluation in Taiwan Game Hens

    Directory of Open Access Journals (Sweden)

    Cheng-Yung Lin

    2014-06-01

    Full Text Available Experiments were conducted to evaluate the effect of an outdoor-grazed raising model on meat composition, physical properties and sensory attributes of Taiwan game hens. Six hundred 1-d old female chicks were raised on a floor for 8 weeks. On day 57, 600 healthy birds, with similar body weight, were selected and randomly assigned to three treatment groups (cage, floor-pen and free-range. The results showed that different feeding models had no effect on drip loss, cooking loss, moisture, crude protein, crude fat, crude ash, zinc and calorie contents in breast meat and moisture content in thigh meat. The free-range group had the lowest fat content in both breast and thigh meat, and the lowest calorie content in thigh meat. The firmness and toughness in both thigh and breast of the free-range group were the highest values (p<0.05. The crude protein, total collagen, zinc and iron contents in thigh meat and total collagen content in breast meat of the free-range group were significantly higher than those of the cage-feeding group (p<0.05. The meat sensory scores of flavor, chewiness and overall acceptability of both thigh and breast meat of the free-range group were significantly (p<0.05 better than those of the other two groups. Moreover, the current findings also indicate that the Taiwan game hens of the free-range feeding model displayed well-received carcass traits and meat quality, with higher scores for flavor, chewiness and overall acceptability for greater sensory satisfaction in both breast and thigh meat. In addition, the thigh meat contained high protein and total collage but low fat, offering a healthier diet choice.

  12. Effect of perches on liver health of hens.

    Science.gov (United States)

    Jiang, S; Hester, P Y; Hu, J Y; Yan, F F; Dennis, R L; Cheng, H W

    2014-07-01

    Fatty liver is a common energy metabolic disorder in caged laying hens. Considering that the egg industry is shifting from conventional cages to alternative housing systems such as enriched cages, the objective of this study was to determine the effects of perches on fat deposition and liver health in laying hens. Three hundred twenty-four 17-wk-old White Leghorn hens were housed in 1 of 4 treatments with 9 hens per cage. Treatment 1 hens never had access to perches during their life cycle. Treatment 2 hens had access to perches during the pullet phase only. Treatment 3 hens had access to perches during the laying phase only. Treatment 4 hens always had access to perches. Liver weight, abdominal fat pad weight, BW, liver fat, and circulating alanine transaminase, aspartate transaminase, and adiponectin were determined. Provision of perches during either the rearing or laying phase did not affect liver health in 71-wk-old hens. However, perch access compared with no perch access during the egg laying phase reduced relative fat pad weight. These results suggest that providing perches as a means of stimulating activity reduced abdominal fat deposition in caged hens during the laying period. However, perch access in caged hens was ineffective in reducing fat deposition in the liver and altering enzyme activities related to improved liver function.

  13. Nest sharing under semi-natural conditions in laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch

    2012-01-01

    problems to laying hens, and egg production may also be negatively affected. Understanding what causes this difference in nest location selection may provide solutions to the problems associated with simultaneous nest sharing. The aims were to investigate whether a commercial strain of laying hens normally...... daily of each nest with regard to number of eggs, position, and materials used. On five mornings nesting behaviour was observed. Nest sharing occurred on all but the first 5 days of egg-laying. The majority of hens (n = 14) chose to visit an occupied nest at least once, but no hens exclusively used......Under natural conditions, the feral hen (Gallus gallus domesticus) will choose a nest location away from the flock, whereas under commercial conditions, the domestic hen will often choose the same nest as other hens have used or are still using. Simultaneous nest sharing causes several welfare...

  14. Effect of light-emitting diode vs. fluorescent lighting on laying hens in aviary hen houses: Part 1 - Operational characteristics of lights and production traits of hens.

    Science.gov (United States)

    Long, H; Zhao, Y; Wang, T; Ning, Z; Xin, H

    2016-01-01

    Light-emitting diode (LED) lights are becoming more affordable for agricultural applications. Despite many lab-scale studies concerning impact of LED on poultry, little research has been documented under field production conditions, especially for laying hens. This 15-month field study was carried out to evaluate the effects of LED vs. fluorescent (FL) lights on laying hens (Dekalb white breed) using 4 (2 pairs) aviary hen houses each at a nominal capacity of 50,000 hens. The evaluation was done regarding operational characteristics of the lights and hen production traits. The results show that spatial distribution of the LED light was less uniform than that of the FL light. Light intensity of the LED light decreased by 27% after 3,360 h use but remained quite steady from 3,360 to 5,760 h use. Eleven out of 762 (1.44%) LED lamps (new at onset of the study) in the 2 houses failed during the 15-month experiment period. The neck area of the LED lamp was hottest, presumably the primary reason for the lamp failure as cracks were noticed in the neck region of all failed LED lamps. No differences were observed in egg weight, hen-day egg production, feed use, and mortality rate between LED and FL regimens. However, hens under the FL had higher eggs per hen housed and better feed conversion than those under the LED during 20 to 70 wk production (P Hens under the LED tended to have less feather uniformity and insulation than those under the FL (P hens under the LED showed a larger median avoidance distance than those under the FL at 36 wk age (P hens under the LED were more alert; but no difference at 60 wk age. More comparative research to quantify behavioral and production responses of different breeds of hens to LED vs. FL lighting seems warranted.

  15. EFFICACY OF PROBIOTICS INTAKE ON INTERNAL MILIEU OF HENS

    Directory of Open Access Journals (Sweden)

    Martin Mellen

    2014-12-01

    Full Text Available The aim of present study was to evaluate the functional efficiency of probiotic preparation on selected blood biochemical parameters of ISA Brown hens. Feed in the experimental group of hens was enriched with a probiotic preparation in the dose of 500g.t-1 consisted of freeze-dried cultures: Lactobacillus bulgaricus LAT 187, L. acidophilus LAT 180, L. helveticus LAT 179, L. delbrueckii ssp. Lactis LAT 182, Streptococcus thermophiles LAT 205, Enterococcus faecium E-253 with concentration of 5.109 (CFU LAB living organisms in 1 gram. Blood samples were collected in 25 and 48 week of hens’ age. Biochemical parameters of mineral profile (calcium, phosphorus, magnesium, sodium, potassium, chlorides, energetic profile (plasma total cholesterol, triglycerides, total proteins, bilirubin, glucose, and activities of serum liver enzymes (aspartate aminotransferase AST, alanine aminotransferase ALT, alkaline phosphatase ALP were analysed using Ecoline kits and a semi-automated clinical chemistry analyser Microlab 300 (Vilat Scientific, Dieren, The Nederland. Probiotic preparation reduced (P<0.05 serum cholesterol and triglycerides content. No significant effects of probiotic on remaining parameters were confirmed.

  16. Transcriptomic profiling of proteases and antiproteases in the liver of sexually mature hens in relation to vitellogenesis

    Directory of Open Access Journals (Sweden)

    Bourin Marie

    2012-09-01

    Full Text Available Abstract Background Most egg yolk precursors are synthesized by the liver, secreted into the blood and transferred into oocytes, to provide nutrients and bioactive molecules for the avian embryo. Three hundred and sixteen distinct proteins have been identified in egg yolk. These include 37 proteases and antiproteases, which are likely to play a role in the formation of the yolk (vitellogenesis, as regulators of protein metabolism. We used a transcriptomic approach to define the protease and antiprotease genes specifically expressed in the hen liver in relation to vitellogenesis by comparing sexually mature and pre-laying chickens showing different steroid milieu. Results Using a 20 K chicken oligoarray, a total of 582 genes were shown to be over-expressed in the liver of sexually mature hens (1.2 to 67 fold-differences. Eight of the top ten over-expressed genes are known components of the egg yolk or perivitelline membrane. This list of 582 genes contains 12 proteases and 3 antiproteases. We found that “uncharacterized protein LOC419301/similar to porin” (GeneID:419301, an antiprotease and “cathepsin E-A-like/similar to nothepsin” (GeneID:417848, a protease, were the only over-expressed candidates (21-fold and 35-fold difference, respectively that are present in the egg yolk. Additionally, we showed the 4-fold over-expression of “ovochymase-2/similar to oviductin” (GeneID:769290, a vitelline membrane-specific protease. Conclusions Our approach revealed that three proteases and antiproteases are likely to participate in the formation of the yolk. The role of the other 12 proteases and antiproteases which are over-expressed in our model remains unclear. At least 1/3 of proteases and antiproteases identified in egg yolk and vitelline membrane proteomes are expressed similarly in the liver regardless of the maturity of hens, and have been initially identified as regulators of haemostasis and inflammatory events. The lack of effect of sex

  17. Paul Henning Krogh on Soil Ecotoxicology

    DEFF Research Database (Denmark)

    Krogh, Paul Henning

    2008-01-01

    In a recent analysis of data from Essential Science Indicators SM from Thomson Reuters , Dr. Paul Henning Krogh was named a Rising Star in the field of Environment & Ecology. His current record in this field includes 48 papers cited a total of 410 times. Dr. Krogh is a Senior Scientist in the Dep...

  18. Vold, svensk uro og Henning Mankell

    DEFF Research Database (Denmark)

    Hansen, Kim Toft

    Paperet undersøger den fiktionelle repræsentation af vold hos Henning Mankell med fokus på Innan frosten fra 2002 og filmatiseringen heraf fra 2005, men med fyldige udblik til såvel andre af Mankells fortællinger og ikke mindst sociologiske og filosofiske diskussioner af volden, voldens forstyrre...

  19. GENETIC CORRELATIONS BETWEEN BEHAVIOURAL RESPONSES AND PERFORMANCE TRAITS IN LAYING HENS.

    Science.gov (United States)

    Rozempolska-Rucińska, Iwona; Zięba, Grzegorz; Kibała, Lucyna; Próchniak, Tomasz Paweł; Łukaszewicz, Marek

    2017-02-23

    The aim of the study was to evaluate genetic correlations between the behavioural profile and performance in laying hens as an indirect answer to the question whether the observed behavioural responses are associated with increased levels of stress in these birds. The assessment of birds' temperament was carried out using the Novel Objects Test. The behavioural test was conducted in two successive generations comprising 9483 Rhode Island White birds (approx. 4700 individuals per generation) and 4326 Rhode Island Red birds (approx. 2100 individuals per generation). Based on the recorded responses, the birds were divided into two groups: a fearful profile (1418 RIW hens and 580 RIR hens) and a brave/curious profile (8065 RIW hens and 3746 RIR hens). The birds were subjected to standard assessment of their performance traits, including SM- age at sexual maturity, ST - shell thickness, SG - egg specific gravity, EW - mean egg weight, IP - initial egg production, and PW/HC - number of hatched chicks. The lineage comprised a three-generation population of birds. Estimation of the components of variance of the behavioural traits was performed with Gibbs sampling (300000 rounds with 100000 burn-in rounds) based on the multi-trait animal model. The analyses revealed negative correlations between the performance traits of the laying hens and the behavioural profile defined as fearful. In the group of fearful RIW birds, delayed sexual maturation (0,22) as well as a decrease in the initial egg production (-0,30), egg weight (-0,54), egg specific gravity (-0,331), shell thickness (-0,11), and the number of hatched chicks (-0,24) could be expected. These correlations were less pronounced in the RIR breed, in which the fearful birds exhibited a decline in hatchability (-0,37), egg specific gravity (-0,11), and the number of hatched chicks (-0,18). There were no correlations in the case of the other traits or they were positive but exhibited a substantial standard error, as for

  20. Organophosphorus poisoning-induced delayed neuropathy hen model induced by triorthocresyl phosphate and phenylmethylsulfonyl fluoride intervention%磷酸三邻甲苯酯诱导鸡迟发神经毒性模型和苯甲基磺酰氟的预处理

    Institute of Scientific and Technical Information of China (English)

    左恩俊; 朴丰源; 姜莹

    2014-01-01

    BACKGROUND:Although incidents of organophosphorus poisoning-induced delayed neuropathy (OPIDN) have been documented for over a century, the molecular mechanisms underlying the axonopathy remain poorly understood. Therefore, OPIDN treatment has been increasingly concerned. OBJECTIVE:To construct the OPIDN hen model induced by triorthocresyl phosphate (TOCP) and to explore the effect of phenylmethylsulfonyl fluoride (PMSF) intervention. METHODS:Adult hens were randomly divided into four groups: two TOCP groups, a PMSF group and a control group. TOCP groups were treated with TOCP by gavage at a single dosage of 1 000 mg/kg and 750 mg/kg respectively; control group was given an equivalent volume of saline by gavage while hens in the PMSF group were subcutaneously injected with 40 mg/kg PMSF 24 hours after 1 000 mg/kg TOCP injection. OPIDN neurological signs were assessed by a six-point graded scale. The changes of the hen weight were recorded. The hens were kiled on day 5 and 21 post-dosing. The samples were cut into 50 nm thick sections and examined by transmission electron microscopy. RESULTS AND CONCLUSION:OPIDN neurological signs such as abnormal gaits progressed in severity with time (P < 0.05), and the hen weight was significantly decreased in TOCP groups (P < 0.05). However, no clinical signs of delayed neurotoxicity were observed in hens of the PMSF group and the control group during the experiment period. The mild mitochondrial sweling and the fragmentation of microfilament and microtubule arrangement in axons were observed on day 5 post-dosing, leaving the other organeles remained unchanged. On day 21, neuronal degeneration was apparent, including sweling of endoplasmic reticulum, abnormal change of mitochondria, and disordered arrangement of cytoskeleton. The optimal dose of TOCP was 1 000 mg/kg. Experimental findings indicate that, OPIDN hen model induced by TOCP and PMSF intervention hen model were successfuly constructed. PMSF intervention significantly

  1. Preferential interactions and the effect of protein PEGylation

    DEFF Research Database (Denmark)

    Holm, Louise Stenstrup; Thulstrup, Peter Waaben; Kasimova, Marina Robertovna;

    2015-01-01

    BACKGROUND: PEGylation is a strategy used by the pharmaceutical industry to prolong systemic circulation of protein drugs, whereas formulation excipients are used for stabilization of proteins during storage. Here we investigate the role of PEGylation in protein stabilization by formulation...... excipients that preferentially interact with the protein. METHODOLOGY/PRINCIPAL FINDINGS: The model protein hen egg white lysozyme was doubly PEGylated on two lysines with 5 kDa linear PEGs (mPEG-succinimidyl valerate, MW 5000) and studied in the absence and presence of preferentially excluded sucrose...... excipients. This suggests that formulation principles using preferentially interacting excipients are similar for PEGylated and non-PEGylated proteins....

  2. Learning generative models for protein fold families.

    Science.gov (United States)

    Balakrishnan, Sivaraman; Kamisetty, Hetunandan; Carbonell, Jaime G; Lee, Su-In; Langmead, Christopher James

    2011-04-01

    We introduce a new approach to learning statistical models from multiple sequence alignments (MSA) of proteins. Our method, called GREMLIN (Generative REgularized ModeLs of proteINs), learns an undirected probabilistic graphical model of the amino acid composition within the MSA. The resulting model encodes both the position-specific conservation statistics and the correlated mutation statistics between sequential and long-range pairs of residues. Existing techniques for learning graphical models from MSA either make strong, and often inappropriate assumptions about the conditional independencies within the MSA (e.g., Hidden Markov Models), or else use suboptimal algorithms to learn the parameters of the model. In contrast, GREMLIN makes no a priori assumptions about the conditional independencies within the MSA. We formulate and solve a convex optimization problem, thus guaranteeing that we find a globally optimal model at convergence. The resulting model is also generative, allowing for the design of new protein sequences that have the same statistical properties as those in the MSA. We perform a detailed analysis of covariation statistics on the extensively studied WW and PDZ domains and show that our method out-performs an existing algorithm for learning undirected probabilistic graphical models from MSA. We then apply our approach to 71 additional families from the PFAM database and demonstrate that the resulting models significantly out-perform Hidden Markov Models in terms of predictive accuracy.

  3. Can Non-Beak Treated Hens be Kept in Commercial Furnished Cages? Exploring the Effects of Strain and Extra Environmental Enrichment on Behaviour, Feather Cover, and Mortality

    Science.gov (United States)

    Morrissey, Krysta L. H.; Brocklehurst, Sarah; Baker, Laurence; Widowski, Tina M.; Sandilands, Victoria

    2016-01-01

    Commercial laying hens are prone to injurious pecking (IP), a common multifactorial problem. A 2 × 2 × 2 factorial design assessed the effects of breed (Lohmann Brown Classic (L) or Hyline Brown (H)), beak treatment (infra-red treated (T) or not (NT)), and environment (extra enrichment (EE) or no extra enrichment (NE)) on mortality, behaviour, feather cover, and beak shape. Hens were allocated to treatments at 16 weeks of age and data were collected every four weeks from age 19 to 71 weeks. Data were analysed in Genstat using mixed models. L hens had higher all and IP-related mortality than H hens (p cages (p bird-to-bird pecking than H and EE hens, respectively (breed p = 0.015, enrichment p = 0.032). More damage to mats and ropes was caused by L and NT hens than by H and T hens, respectively (age × breed p bird-to-bird pecking, the enrichments were less effective at reducing feather cover damage and mortality than expected. PMID:26927190

  4. Low-fiber alfalfa (Medicago sativa L.) meal in the laying hen diet: effects on productive traits and egg quality.

    Science.gov (United States)

    Laudadio, V; Ceci, E; Lastella, N M B; Introna, M; Tufarelli, V

    2014-07-01

    This study was designed to determine the effects on laying performance and egg quality resulting from partial substitution of soybean meal (SBM) with low-fiber alfalfa (LFA; Medicago sativa L.) meal in the diet of early-phase laying hens. ISA Brown layers, 18 wk of age, were randomly allocated to 2 dietary treatments and fed for 10 wk. The hens were fed 2 wheat middling-based diets: a control diet, which contained SBM (15% of diet), and a test diet containing LFA (15% of diet) as the main protein source. Low-fiber alfalfa meal was obtained by a combination of sieving and air-classification processes. Feed intake was recorded daily, and egg production was calculated on a hen-day basis; eggs from each group were weekly collected to evaluate egg components and quality. The partial substitution of SBM with LFA had no adverse effect on growth performance of early-phase laying hens. Egg production and none of the egg-quality traits examined were influenced by dietary treatment, except for yolk color (P alfalfa meal in the laying-hen diet can positively influence yolk quality without adversely affecting productive traits. © 2014 Poultry Science Association Inc.

  5. Utilisation of dried caged-hen manure and cassava peels for intensive sheep production.

    Science.gov (United States)

    Okeudo, N J; Adegbola, A A

    1993-11-01

    Twenty grower ewes with an average weight of 14.3 +/- 3.7 kg were allotted to 5 dietary treatments. The diets contained 0, 13, 25, 35 and 45% dried caged-hen manure which replaced 0, 25, 50, 75 and 100%, respectively of the conventional protein supplements. The animals were fed 55.0 g/w0.75 kg/day of the concentrate food during a 104 days growth study. Air dried cassava peels and water were also provided ad libitum. The differences in average total dry matter intake were not statistically significant. The higher the manure content in the diets, the lower the energy content and the higher the cassava peels intake. No statistical differences were found in growth rates. The efficiency of food conversion decreased progressively though insignificantly. It was concluded that sheep can be fed caged-hen manure as the sole protein supplement in cassava peel based diets.

  6. Determination of space use by laying hens using kinematic analysis.

    Science.gov (United States)

    Mench, Joy A; Blatchford, Richard A

    2014-04-01

    Two states in the United States now have legislation requiring that laying hens be provided with sufficient space to perform particular behaviors. To provide a framework for translating these performance standards into a space requirement, kinematic analysis was used to measure the amount of space needed for White Leghorn hens to stand, turn around 180°, lie down, and wing flap. Hyline W-36 hens (n = 9) were marked on the tops of their heads and the tips of both wings and 3 toes with black livestock marker. Each hen was then placed in a floor pen (91.4 × 91.4 cm) and filmed using 2 high-speed cameras. The resulting images were processed using a software program that generated 3-dimensional space use for each behavior. Because none of the hens lay down in the test pen, the 2-dimensional space required for lying was determined by superimposing a grid over videos of the hens lying down in their home cages. On average, hens required a mean area of 563 (± 8) cm(2) to stand, 1,316 (± 23) cm(2) to turn around, 318 (± 6) cm(2) to lie down, and 1,693 (± 136) cm(2) to wing flap. The mean heights used were 34.8 (± 1.3) cm for standing, 38.6 (± 2.3) cm for turning, and 49.5 (± 1.8) cm for wing flapping. However, space requirements for hens housed in multiple-hen groups in cage or noncage systems cannot be based simply on information about the space required for local movement by a single hen. It must also incorporate consideration of the tendency of hens in a flock to synchronize their behaviors. In addition, it must include not just local movement space but also the space that hens may need to use for longer-distance movements to access resources such as food, water, perches, and nest boxes.

  7. Modelling Hen Harrier Dynamics to Inform Human-Wildlife Conflict Resolution: A Spatially-Realistic, Individual-Based Approach: e112492

    National Research Council Canada - National Science Library

    Johannes P M Heinonen; Stephen C F Palmer; Steve M Redpath; Justin M J Travis

    2014-01-01

      Individual-based models have gained popularity in ecology, and enable simultaneous incorporation of spatial explicitness and population dynamic processes to understand spatio-temporal patterns of populations...

  8. Paul Henning Krogh on Soil Ecotoxicology

    DEFF Research Database (Denmark)

    Krogh, Paul Henning

    2008-01-01

    In a recent analysis of data from Essential Science Indicators SM from Thomson Reuters , Dr. Paul Henning Krogh was named a Rising Star in the field of Environment & Ecology. His current record in this field includes 48 papers cited a total of 410 times. Dr. Krogh is a Senior Scientist in the Dep......In a recent analysis of data from Essential Science Indicators SM from Thomson Reuters , Dr. Paul Henning Krogh was named a Rising Star in the field of Environment & Ecology. His current record in this field includes 48 papers cited a total of 410 times. Dr. Krogh is a Senior Scientist...... in the Department of Terrestrial Ecology at the National Environmental Research Institute, part of the University of Aarhus in Silkeborg, Denmark. This month, he talks with ScienceWatch.com correspondent Simon Mitton about his highly cited work. View Article...

  9. Effects of faba beans with different concentrations of vicine and convicine on egg production, egg quality and red blood cells in laying hens.

    Science.gov (United States)

    Lessire, M; Gallo, V; Prato, M; Akide-Ndunge, O; Mandili, G; Marget, P; Arese, P; Duc, G

    2016-12-29

    The faba bean (Vicia faba L.) is a potential source of proteins for poultry, mainly for laying hens whose protein requirements are lower than those of other birds such as growing broilers and turkeys. However, this feedstuff contains anti-nutritional factors, that is, vicine (V) and convicine (C) that are already known to reduce laying hen performance. The aim of the experiment reported here was to evaluate the effects of a wide range of dietary V and C concentrations in laying hens. Two trials were performed with laying hens fed diets including 20% or 25% of faba bean genotypes highly contrasting in V+C content. In Trial 1, faba beans from two tannin-containing cultivars, but with high or low V+C content were dehulled in order to eliminate the tannin effect. In addition to the contrasting levels of V+C in the two cultivars, two intermediate levels of V+C were obtained by mixing the two cultivars (70/30 and 30/70). In Trial 2, two isogenic zero-tannin faba bean genotypes with high or low V+C content were used. In both trials, a classical corn-soybean diet was also offered to control hens. Each experimental diet was given to 48 laying hens for 140 (Trial 1) or 89 (Trial 2) days. Laying performance and egg quality were measured. The redox sensitivity of red blood cells (RBCs) was assessed by measuring hemolysis and reduced glutathione (GSH) concentration in these cells. Egg weight was significantly reduced by the diets containing the highest concentrations of V+C (Phens fed high V+C diets. A decrease in GSH concentration in RBCs of hens fed the highest levels of V+C was observed. Faba bean genotypes with low concentrations of V+C can therefore be used in laying hen diets up to 25% without any detrimental effects on performance levels or egg characteristics, without any risk of hemolysis of RBCs.

  10. Neural network models of protein domain evolution

    OpenAIRE

    Sylvia Nagl

    2000-01-01

    Protein domains are complex adaptive systems, and here a novel procedure is presented that models the evolution of new functional sites within stable domain folds using neural networks. Neural networks, which were originally developed in cognitive science for the modeling of brain functions, can provide a fruitful methodology for the study of complex systems in general. Ethical implications of developing complex systems models of biomolecules are discussed, with particular reference to molecu...

  11. In vitro penetration of Salmonella Enteritidis through yolk membranes of eggs from 6 genetically distinct commercial lines of laying hens.

    Science.gov (United States)

    Gast, R K; Jones, D R; Anderson, K E; Guraya, R; Guard, J; Holt, P S

    2010-08-01

    Although deposition of Salmonella Enteritidis inside yolks is less common than deposition in albumen or on the vitelline (yolk) membrane in naturally contaminated eggs laid by infected hens, bacterial migration into the yolk to reach its nutrient-rich contents could lead to extensive multiplication. The present study used an in vitro egg contamination model to assess the ability of small initial numbers of Salmonella Enteritidis to penetrate the vitelline membrane and multiply inside yolks of eggs laid by 6 genetically distinct commercial lines of hens during 24 h of storage at 30 degrees C. Eggs from each line were tested at 4 different hen ages by inoculation of approximately 100 cfu of Salmonella Enteritidis onto the outside of the vitelline membranes of intact yolks in plastic centrifuge tubes and then adding back the albumen into each tube before incubation. Overall, the frequency of penetration of Salmonella Enteritidis into the yolk contents of eggs from individual lines of hens ranged from 30 to 58% and the mean concentration of Salmonella Enteritidis in yolk contents after incubation ranged from 0.8 to 2.0 log(10) cfu/mL. For both of these parameters, values for one hen line were significantly higher than for 2 other lines, but no other differences were observed. Hen age did not have a significant effect on egg yolk penetration by Salmonella Enteritidis. These results indicate that opportunities for the migration and growth of small initial numbers of Salmonella Enteritidis to attain more dangerous levels inside contaminated eggs during storage at warm temperatures can sometimes vary between different lines of laying hens.

  12. Modeling protein synthesis from a physicist's perspective: a toy model

    CERN Document Server

    Basu, A; Basu, Aakash; Chowdhury, Debashish

    2007-01-01

    Proteins are polymers of amino acids. These macromolecules are synthesized by intracellular machines called {\\it ribosome}. Although, traditionally, the experimental investigation of protein synthesis has been an active area of research in molecular cell biology, important quantitative models of this phenomenon have been reported mostly in the research journals devoted to statistical physics and related interdisciplinary topics. From the perspective of a physicist, protein synthesis is a phenomenon of {\\it classical transport of interacting ribosomes on a messenger RNA (mRNA) template} that dictates the sequence of the amino acids on the protein. Here we bring this frontier area of contemporary research into the classroom by appropriate simplification of the models and methods. In particular, we develope a simple toy model and analyze it by some elementary techniques of non-equilibrium statistical mechanics to predict the average rate of protein synthesis and their spatial organization in the steady-state.

  13. Chlorinated drinking water for lightweight laying hens

    Directory of Open Access Journals (Sweden)

    A.F. Schneider

    Full Text Available ABSTRACT The study aimed to evaluate the effect of different levels of chlorine in drinking water of laying hens on zootechnical performance, eggs shell quality, hemogasometry levels and calcium content in tibia. 144 Hy-Line laying hens, 61 weeks old, were used distributed in 24 metabolism cages. They were subjected to water diets, for a period of 28 days, using sodium hypochlorite as a chlorine source in order to obtain the following concentrations: 5ppm (control, 20ppm, 50ppm, and 100ppm. Their performance was evaluated through water consumption, feed intake, egg production and weight, egg mass, feed conversion. Shell quality was measured by specific gravity. At the end of the experiment, arterial blood was collected for blood gas level assessment and a poultry of each replicate was sacrificed to obtain tibia and calcium content measurement. There was a water consumption reduction from 20ppm of chlorine and feed intake reduction in poultry receiving water with 100ppm of chlorine. The regression analysis showed that the higher the level of chlorine in water, the higher the reduction in consumption. There were no differences in egg production and weight, egg mass, feed conversion, specific gravity, tibia calcium content, and hemogasometry levels (hydrogenionic potential, carbon dioxide partial pressure, oxygen partial pressure, sodium, potassium, chloride, bicarbonate, carbon dioxide total concentration, anion gap and oxygen saturation. The use of levels above 5ppm of chlorine is not recommended in the water of lightweight laying hens.

  14. Modelling of DNA-protein recognition

    Science.gov (United States)

    Rein, R.; Garduno, R.; Colombano, S.; Nir, S.; Haydock, K.; Macelroy, R. D.

    1980-01-01

    Computer model-building procedures using stereochemical principles together with theoretical energy calculations appear to be, at this stage, the most promising route toward the elucidation of DNA-protein binding schemes and recognition principles. A review of models and bonding principles is conducted and approaches to modeling are considered, taking into account possible di-hydrogen-bonding schemes between a peptide and a base (or a base pair) of a double-stranded nucleic acid in the major groove, aspects of computer graphic modeling, and a search for isogeometric helices. The energetics of recognition complexes is discussed and several models for peptide DNA recognition are presented.

  15. Molecular characterization of complete genome of Japanese encephalitis virus HEN0701 strain isolated from swine%猪源乙型脑炎病毒HEN0701株全基因组的分子特征

    Institute of Scientific and Technical Information of China (English)

    郑浩; 孙春清; 袁世山

    2011-01-01

    Four overlapping cDNA fragments from Japanese encephalitis virus(JEV) HEN0701 strain were cloned into pCR Ⅱ-Blunt-TOPO vector, followed by determination of complete genomic cDNA sequence. The complete genome of HEN0701 strain was 10 965 nucleotides in length,including a long open reading frame from 97th to 10395th nucleotide in the genome. Comparing to 6 strains of genotype Ⅰ (G Ⅰ)JEV and 5 strains of G Ⅲ, HEN0701 had high nucleotide sequence identity with G Ⅰ strains, but low nucleotide sequence identity with G Ⅲ strains in both complete genome and each gene. However, HEN0701 had high amino acid sequence identity with both G Ⅰ and GⅢ strains in both full polyprotein and each viral protein. Phylogenetic trees based on the C,E,NS3 and NS5 gene sequences of HEN0701 and 11 JEV strains were constructed with the software MEGA 5. Four phylogenetic trees had similar topology,indicating that the four genes from JEV had the similar evolutionary trend.%将乙型脑炎病毒HEN0701株基因组RNA分4段进行RT-PCR扩增,并克隆入pCRⅡ-Blunt-TOPO载体中,测定全长cDNA序列.以MapDraw软件分析了乙型脑炎病毒HEN0701株的基因组结构,并将病毒基因组分成2个非编码区和10个基因,比较了HEN0701株和11株乙型脑炎病毒在全基因组和各基因的核苷酸及推导氨基酸的同源性.以MEGA5软件绘制HEN0701株和11株病毒C、E、NS3、NS5 基因的进化树.结果显示,HEN0701株全基因组为10965 nt,包含一长10299 nt的开放阅读框.在核苷酸水平,HEN0701株与GⅠ分离株的全基因组和各基因的同源性均高,而与GⅢ分离株则较低;而在氨基酸水平,HEN0701株与GⅠ分离株在多聚蛋白和各病毒蛋白的同源性和HEN0701株与GⅢ分离株的相近.进化分析显示,不同基因进化树的拓扑结构相近,12株病毒的C、E、NS3、NS5基因进化方向相同,GⅠ分离株和GⅢ分离株间C基因进化距离最近.

  16. Transfection and expression of exogenous gene in laying hens oviduct in vitro and in vivo

    Institute of Scientific and Technical Information of China (English)

    GAO Bo; SUN Huai-chang; SONG Cheng-yi; WANG Zhi-yue; CHEN Qin; SONG Hong-qin

    2005-01-01

    To examine whether or not the regulatory sequence of chicken ovalbumin gene can drive transgene expression specifically in hen oviduct, the authors constructed an oviduct-specific expression vector (pOV), containing 3.0 kilobases (kb) of the 5'-flanking sequence and 3.0 kb of the 3'-flanking sequence of the chicken ovalbumin gene. Jellyfish green fluorescence protein (EGFP) reporter gene and bacterial LacZ reporter gene were respectively inserted into the downstream of the 5'-regulatory region.The recombinants were named as pOVEGFP and pOVLacZ. Two transfer systems, in vitro and in vivo, were used to verify the function of the vector. In vitro, the plasmid DNA pOVEGFP and pEGFP-N1 were transfected respectively by the polyethyleneimine procedure into the primary chicken oviduct epithelium (PCOE) and fibroblasts cells isolated from laying hens. In vivo, the recombinant vector pOVLacZ was injected into egg-laying hens via wing vein and the tissues were collected for RT-PCR analysis.The results showed that expression of pEGFP-N1 was achieved at low level in oviduct epithelial cells and at high level in fibroblasts, but that the recombinant vector was not expressed in both cells. RT-PCR analysis showed that the LacZ gene was transcribed in the oviduct, but not in the heart, liver, kidney and spleen of the injected hens. Accordingly, the ?-galactosidase activity was only detected in the oviduct magnum (116.7 mU/ml) and eggs (16.47 mU/ml). These results indicated that the cloned regulation regions of chicken ovalbumin gene could drive exogenous gene expression specifically in the oviducts of hens. In vivo gene injection via wing vein may serve as a rapid production system of recombinant proteins in chicken eggs. In addition, the cultured primary oviduct cells from laying hens were not efficient temporary expression systems for analyzing the function of regulating elements of ovalbumin gene.

  17. Effect of feeding low-fiber fraction of air-classified sunflower (Helianthus annus L.) meal on laying hen productive performance and egg yolk cholesterol.

    Science.gov (United States)

    Laudadio, V; Ceci, E; Lastella, N M B; Tufarelli, V

    2014-11-01

    The present study was designed to determine the effect on laying performance and egg quality resulting from total substitution of soybean meal (SBM) with low-fiber sunflower meal (SFM; Helianthus annus L.) meal in diet of hens. ISA Brown layers, 28 wk of age, were randomly allocated to 2 dietary treatments and fed for 10 wk. The hens were kept in a free-range environment and fed 2 wheat middling-based diets consisting of a control diet, which contained SBM (153 g/kg of diet), and a test diet containing low-fiber SFM (160 g/kg of diet) as the main protein source. Each dietary treatment was replicated 4 times. Low-fiber SFM was obtained by a combination of sieving and air classification processes. Feed consumption was recorded daily and egg production was calculated on a hen-day basis; eggs from each group were collected weekly to evaluate egg components and quality. The total substitution of SBM with low-fiber SFM had no adverse effect on growth performance of laying hens. Egg production and none of egg quality traits examined were influenced by dietary treatment, except for yolk color (P hens fed the low-fiber SFM diet. Including low-fiber SFM decreased serum and egg yolk total cholesterol and low-density lipoprotein cholesterol concentrations (P laying hens to improve egg quality and to develop low-cholesterol eggs.

  18. Peningkatan Produktivitas Ayam Petelur Melalui Pemberian Ekstrak Etanol Daun Kemangi (INCREASED LAYING HENS PRODUCTIVITY THROUGH THE ADMINISTRATION OF ETHANOL EXTRACT OF KEMANGI LEAVES

    Directory of Open Access Journals (Sweden)

    Andriyanto .

    2014-08-01

    Full Text Available Empirically, kemangi leaves reported to increase health quality in human and livestock. Thepreliminary study was designed to explore the potency of ethanol extract of kemangi leaves to increaselaying hens performance. Sixteen laying hens (pullet were divided into 4 groups and repeated 4 times.Control group was laying hen administered aquadest orally, treated group was laying hen administeredextract of kemangi leaves orally at a dose of 1, 2, and 3 mg/kg BW, respectively. Every day, the experimentallaying hens were fed for 3 times and drinking water was provided ad libitum. Variables observed were thenumber of eggs, egg weight, time of first laying, egg laying intervals, egg quality ( water content, crudeprotein, and crude fat, and liver function (SGPT and SGOT values . Results of this research showed thatadministration of kemangi leaves extract at a dose of 3 mg/kg BW significantly increased the number ofegg production and egg weight (p<0.05. Time of first laying and laying interval did not show any significantdifference among treatments. Examination of moisture, crude protein, and crude fat content of the eggindicated that the administration of kemangi leaves extract did not affect egg quality. Extract of kemangileaves decreased SGPT and SGOT values that indicated improvement of liver function. It was concludedthat administration of ethanol extract of kemangi leaves could increase laying hens productivity byimprovement of liver function that is critical in vitellogenesis.

  19. Selected pharmacokinetic parameters for cefovecin in hens and green iguanas

    DEFF Research Database (Denmark)

    Thuesen, Line Risager; Bertelsen, Mads Frost; Brimer, Leon

    2009-01-01

    hens and green iguanas, following subcutaneous injections with 10 mg cefovecin / kg bodyweight. Preliminary studies in eight additional species of birds and reptiles were performed and results were compared with the parameters found in hens and green iguanas. The kinetics were characterized by rapid...

  20. Housing system and laying hen strain impacts on egg microbiology.

    Science.gov (United States)

    Jones, D R; Anderson, K E

    2013-08-01

    Alternative hen housing is becoming more commonplace in the egg market. However, a complete understanding of the implications for alternative housing systems on egg safety has not been achieved. The current study examines the impact of housing Hy-Line Brown, Hy-Line Silver Brown, and Barred Plymouth Rock hens in conventional cage, cage-free, and free range egg production systems on shell microbiology. Eggs were collected at 4 sampling periods. Egg shell emulsion pools were formed and enumerated for total aerobic organisms, Enterobacteriaceae, and yeast and mold counts. Hy-Line Brown and Hy-Line Silver Brown hens produced eggs with significantly (P hen strain with Hy-Line Silver Brown having the greatest (4.57 log cfu/mL). Hy-Line Brown and Barred Plymouth Rock hens produced eggs with significantly different (P hen strains. There were no differences within each strain among housing systems for yeast and mold contamination. The study shows that hen strain has an effect on egg microbial levels for various housing systems, and egg safety should be considered when making hen strain selections for each housing system.

  1. Microbiological impact of three commercial laying hen housing systems

    Science.gov (United States)

    Hen housing for commercial egg production continues to be a societal and regulatory concern. Controlled studies have examined various aspects of egg safety but a comprehensive assessment of commercial hen housing systems in the US has not been conducted. The current study is part of a holistic, mu...

  2. The effect of feeding clinoptilolite (zeolite) to laying hens

    African Journals Online (AJOL)

    housed in individual cages in a naturally ventilated laying house and fed the four ... noticed in the days to f irst egg, number of eggs laid per hen, egg size ... of feed nitrogen in animal nutrition, to reduce intestinal disease in pigs and .... Table 3 Mean performance data of hens fed diets with and without clinoptilolite. 109. Diet.

  3. Quality of eggs from different laying hen production systems, from indigenous breeds and specialty eggs.

    Science.gov (United States)

    Lordelo, M; Fernandes, E; Bessa, R J B; Alves, S P

    2016-11-02

    Consumers are concerned about the quality of commercially available eggs. Eggs used in this study were marketed in Portugal and originated from laying hens raised in cages, barns, free-range, organic eggs, and eggs enriched with n-3 polyunsaturated fatty acids (PUFA), and from native Portuguese breeds. The eggs were analyzed for chemical and physical properties. Results indicated that yolk color was lighter in organic eggs and darker in n-3 PUFA enriched eggs. Eggs from caged hens had lower Haugh units in contrast with organic eggs. Caged hens produced eggs with a higher protein content while organic eggs had the lowest level of protein in the albumen. As might be expected, eggs enriched in n-3 PUFA had the highest n-3 PUFA content. Choosing an egg by its production system or labeling specificities may not be a guarantee of superior product quality. The layer genotype, age, diet, and the quality of the range also may affect egg properties. Due to a different layer diet, enriched eggs seem to be of superior quality.

  4. INTERNAL AND EXTERNAL QUALITY OF COMMERCIAL LAYING HENS EGGS WITH NORMAL AND VITREOUS EGGSHELL

    Directory of Open Access Journals (Sweden)

    Daniela Reis Vilela

    2016-10-01

    Full Text Available The objective of this study was to evaluate the internal and external quality of eggs classified as eggs with normal eggshell and eggs with vitreous eggshell, produced by hens at three different ages. Forty-five eggs of each eggshell type, normal and vitreous, were sampled at the ages of 30, 50, and 70 weeks. The weight of the egg, in both types of eggshell, increased with the advancing age of the hen. Higher concentration of calcium was found in eggs with normal eggshells comparing to eggs with vitreous eggshells. The eggshell type did not affect phosphorus percentage. The mineral deposition of the eggshell was constant. The skin thickness increased irrespective of the shell along the reproductive life of the chicken and decreased when the bird became older. The percentage of albumen increased, while the percentage of albumen protein and pH decreased throughout the ages. Percentage of egg yolk, humidity, and pH decreased with increase of age of the laying hen, whereas crude protein and lipid increased. Eggs with vitreous eggshell showed eggshell with lower quality compared to those with normal eggshell, without, however, compromising the internal quality of albumen and yolk. Keywords: egg quality; eggshell types; physical analysis.

  5. Hydration dynamics near a model protein surface

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Daniela; Hura, Greg; Head-Gordon, Teresa

    2003-09-01

    The evolution of water dynamics from dilute to very high concentration solutions of a prototypical hydrophobic amino acid with its polar backbone, N-acetyl-leucine-methylamide (NALMA), is studied by quasi-elastic neutron scattering and molecular dynamics simulation for both the completely deuterated and completely hydrogenated leucine monomer. We observe several unexpected features in the dynamics of these biological solutions under ambient conditions. The NALMA dynamics shows evidence of de Gennes narrowing, an indication of coherent long timescale structural relaxation dynamics. The translational water dynamics are analyzed in a first approximation with a jump diffusion model. At the highest solute concentrations, the hydration water dynamics is significantly suppressed and characterized by a long residential time and a slow diffusion coefficient. The analysis of the more dilute concentration solutions takes into account the results of the 2.0M solution as a model of the first hydration shell. Subtracting the first hydration layer based on the 2.0M spectra, the translational diffusion dynamics is still suppressed, although the rotational relaxation time and residential time are converged to bulk-water values. Molecular dynamics analysis shows spatially heterogeneous dynamics at high concentration that becomes homogeneous at more dilute concentrations. We discuss the hydration dynamics results of this model protein system in the context of glassy systems, protein function, and protein-protein interfaces.

  6. Predicting Protein Secondary Structure with Markov Models

    DEFF Research Database (Denmark)

    Fischer, Paul; Larsen, Simon; Thomsen, Claus

    2004-01-01

    we are considering here, is to predict the secondary structure from the primary one. To this end we train a Markov model on training data and then use it to classify parts of unknown protein sequences as sheets, helices or coils. We show how to exploit the directional information contained......The primary structure of a protein is the sequence of its amino acids. The secondary structure describes structural properties of the molecule such as which parts of it form sheets, helices or coils. Spacial and other properties are described by the higher order structures. The classification task...

  7. Arginine, soy isoflavone and hydroxypropylmethylcellulose have protective effects against obesity in broiler breeder hens fed on high-energy diets.

    Science.gov (United States)

    Khalaji, S; Zaghari, M; Ganjkhanloo, M; Ghaziani, F

    2013-01-01

    1. The present study was undertaken to determine the effects of arginine, soy isoflavone (ISF) and hydroxypropylmethylcellulose (HPMC) on obesity in broiler breeder hens. 2. A total of 320 Cobb 500 hens, 45 weeks of age, were assigned to 64 floor pens. The experiment was conducted as a completely randomised design in a factorial arrangement (2 × 2 × 2 × 2) with 4 replicates of 5 hens in each pen. Factors included two concentrations of HPMC (0 and 1%), two concentrations of arginine (8.4 and 12 g/kg), two concentrations of ISF (zero and three times more than that present in basal diets) and two contents of energy (11.7 and 14.6 MJ/kg). Performance criteria and blood characteristics of hens were measured during the experimental period. Expression of genes involved in lipid metabolism was determined in the liver at 55 weeks of age. 3. Hens given high-energy diets showed increased BW (body weight), ovary weight and abdominal fat pad and enhanced plasma glucose, triglyceride (TG), cholesterol, haemoglobin, haematocrit and low lymphocyte percentages. The expression of malic enzyme, peroxisome proliferator-activated receptor-α (PPARα), peroxisome proliferator-activated receptor-γ (PPARγ) and inducible nitric oxide (iNOS) increased and sterol regulatory element binding protein-1c (SREBP1c) decreased with increasing energy content of diets. Arginine addition decreased TG, cholesterol and A1-c haemoglobin concentration and increased PPARα, PPARγ and iNOS expression. Inclusion of ISF and HPMC decreased BW, egg weight, plasma TG, cholesterol and increased egg production and also enhanced PPARγ and iNOS expression. Significant interactions were observed between energy concentration and ISF and HPMC on BW. 4. The results of the current study revealed that ISF, HPMC and arginine have beneficial effects on controlling the metabolism of obese broiler breeder hens and using a mix of these products minimises the harmful effects of obesity.

  8. Effect of mechanical denaturation on surface free energy of protein powders

    OpenAIRE

    Mohammad, Mohammad Amin; Grimsey, Ian M.; Forbes, Robert T.; Blagbrough, Ian S; Barbara R. Conway

    2016-01-01

    Globular proteins are important both as therapeutic agents and excipients. However, their fragile native\\ud conformations can be denatured during pharmaceutical processing, which leads to modification of\\ud the surface energy of their powders and hence their performance. Lyophilized powders of hen eggwhite\\ud lysozyme and �-galactosidase from Aspergillus oryzae were used as models to study the effects\\ud of mechanical denaturation on the surface energies of basic and acidic protein powders, r...

  9. Gregarious nesting - An anti-predator response in laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch

    2012-01-01

    Gregarious nesting can be defined as a behaviour that occurs when a laying hen (Gallus gallus domesticus) given the choice between an occupied and an unoccupied nest site chooses the occupied nest site. It occurs frequently in flocks of laying hens kept under commercial conditions, contrasting...... the behaviour displayed by feral hens that isolate themselves from the flock during nesting activities. What motivates laying hens to perform gregarious nesting is unknown. One possibility is that gregarious nesting is an anti-predator response to the risk of nest predation emerging from behavioural flexibility...... in nesting strategy. The aim of the present experiment was to investigate whether gregarious nesting due to behavioural flexibility in nesting strategy is an anti-predator response. Twelve groups of 14–15 Isa Warren hens age 44 weeks were housed in pens each containing three adjacent roll-out nest boxes...

  10. Anti-sperm antibodies and fertility of turkey hens.

    Science.gov (United States)

    McCorkle, F M; Christensen, V L; Thaxton, J P

    1983-11-01

    Anti-sperm antibody titers increase with time in serum of turkey hens following a standard production schedule of artificial insemination (AI). In hens receiving intravenous (IV) or intraperitoneal (IP) additional AI, serum anti-sperm antibody levels increase more rapidly after a lag phase. A single injury to the oviduct also resulted in increased anti-sperm antibodies similar to IV and IP groups. This is a new observation that a single injury increased antibody titers to spermatozoa equal in IV and/or IP injections. A negative correlation between serum anti-sperm antibody titers for IV, IP and injury to oviduct and fertility of these groups was observed. Hens of IV and injury to oviduct groups with high levels of anti-sperm antibodies in the last 2 weeks of production had significantly lower fertility than hens with low levels of antibodies and control hens.

  11. Overall welfare assessment of laying hens: Comparing science-based, environmental-based and animal-based assessments

    NARCIS (Netherlands)

    Shimmura, T.; Bracke, M.B.M.; Mol, de R.M.; Hirahara, S.; Tanaka, T.

    2011-01-01

    To increase the validity of evaluations and facilitate expansion and maintenance of assessment systems, we constructed a database of studies on the welfare of laying hens around the world. On the basis of this database, we devised a science-based welfare assessment model. Our model includes measurem

  12. Ammonia emission and nutrient load in outdoor runs of laying hens

    NARCIS (Netherlands)

    Aarnink, A.J.A.; Hol, J.M.G.; Beurskens, A.G.C.

    2006-01-01

    Ammonia emission and nutrient load in outdoor runs of laying hens were measured at a commercial farm with an outdoor run for 3000 hens, and at an experimental farm with two outdoor runs, each for approximately 250 hens. Ammonia emission was recorded at 5, 10,15 and 20 m from the hen house, using the

  13. Model-building codes for membrane proteins.

    Energy Technology Data Exchange (ETDEWEB)

    Shirley, David Noyes; Hunt, Thomas W.; Brown, W. Michael; Schoeniger, Joseph S. (Sandia National Laboratories, Livermore, CA); Slepoy, Alexander; Sale, Kenneth L. (Sandia National Laboratories, Livermore, CA); Young, Malin M. (Sandia National Laboratories, Livermore, CA); Faulon, Jean-Loup Michel; Gray, Genetha Anne (Sandia National Laboratories, Livermore, CA)

    2005-01-01

    We have developed a novel approach to modeling the transmembrane spanning helical bundles of integral membrane proteins using only a sparse set of distance constraints, such as those derived from MS3-D, dipolar-EPR and FRET experiments. Algorithms have been written for searching the conformational space of membrane protein folds matching the set of distance constraints, which provides initial structures for local conformational searches. Local conformation search is achieved by optimizing these candidates against a custom penalty function that incorporates both measures derived from statistical analysis of solved membrane protein structures and distance constraints obtained from experiments. This results in refined helical bundles to which the interhelical loops and amino acid side-chains are added. Using a set of only 27 distance constraints extracted from the literature, our methods successfully recover the structure of dark-adapted rhodopsin to within 3.2 {angstrom} of the crystal structure.

  14. The influence of dietary taurine and reduced housing density on hepatic functions in laying hens.

    Science.gov (United States)

    Ma, Zili; Zhang, Jinqiu; Ma, Haitian; Dai, Bin; Zheng, Liuhai; Miao, Jinfeng; Zhang, Yuanshu

    2014-07-01

    To investigate the influence of dietary taurine and reduced housing density on hepatic functions in laying hens, green-shell laying hens were randomly assigned to 3 groups: a free-range group, a caged group with low-density, and a caged group with high-density. Each group was further divided into the control (C) and taurine-treatment (T) groups. All the test birds were fed the same basic diet, except that the T groups were supplemented with 0.1% taurine. After 15 d, sera and liver were aseptically collected. The results show that dietary taurine supplementation and reduced housing density significantly attenuated physiopathological changes in the liver. When compared with the free-range group, serum alanine aminotransterase and aspartate aminotransterase in the caged hens were significantly higher and were deceased by taurine (P caged hens was higher than that in free-range hens, and taurine reduced serum inducible nitric oxide synthase activities in the low-density group (P < 0.05). Nuclear factor-κB DNA-binding activity increased significantly in the high-density housing group when compared with the other 2 housing patterns and was decreased by taurine (P < 0.05). Taurine reduced the expression of tumor necrosis factor-α mRNA in all 3 rearing patterns, IL-4 mRNA expression in the high-density group, and IL-10 in the low-density group (P < 0.05). Malondialdehyde levels decreased in serum and liver from T groups and serum total antioxidation capability levels increased significantly (P < 0.05) in the low-density group. Dietary taurine supplementation decreased acetyl-CoA and sterol regulatory element-binding protein-1c mRNA expression in the high-density groups (P < 0.05). Taurine significantly increased lipoprotein lipase mRNA expression in the high-density group and peroxisome proliferator receptor mRNA expression both in the low- and high-density groups (P < 0.05). Taurine supplementation reduced total cholesterol levels in the low- and high-density groups

  15. Protein Folding: Search for Basic Physical Models

    Directory of Open Access Journals (Sweden)

    Ivan Y. Torshin

    2003-01-01

    Full Text Available How a unique three-dimensional structure is rapidly formed from the linear sequence of a polypeptide is one of the important questions in contemporary science. Apart from biological context of in vivo protein folding (which has been studied only for a few proteins, the roles of the fundamental physical forces in the in vitro folding remain largely unstudied. Despite a degree of success in using descriptions based on statistical and/or thermodynamic approaches, few of the current models explicitly include more basic physical forces (such as electrostatics and Van Der Waals forces. Moreover, the present-day models rarely take into account that the protein folding is, essentially, a rapid process that produces a highly specific architecture. This review considers several physical models that may provide more direct links between sequence and tertiary structure in terms of the physical forces. In particular, elaboration of such simple models is likely to produce extremely effective computational techniques with value for modern genomics.

  16. Influence of substituting dietary soybean for air-classified sunflower (Helianthus annuus L.) meal on egg production and steroid hormones in early-phase laying hens.

    Science.gov (United States)

    Laudadio, V; Ceci, E; Nahashon, S N; Introna, M; Lastella, N M B; Tufarelli, V

    2014-02-01

    Soybean meal (SBM) is the most widely and expensive protein source used in the formulation of poultry diets; however, when the price of SBM increases, poultry nutritionists seek alternative sources that are more economical in formulating least-cost rations. This research aimed to evaluate the effects of dietary air-classified sunflower meal (SFM) on some productive parameters and plasma steroid hormones in laying hens. In this trial, 20-week-old laying hens (ISA Brown strain) in the early phase of production were randomly assigned to two groups and fed wheat middlings-based diets containing soybean (135 g/kg; 48% CP) or air-classified SFM (160 g/kg; 41% CP) as the main protein source. Laying performance, egg size and feed conversion ratio were evaluated for 10 week. Plasma steroid hormones (progesterone and oestradiol) in the hens were quantified weekly. Substituting SBM with air-classified SFM did not change (p > 0.05) the hens' growth performance, whereas feed consumption and efficiency were positively influenced (p hormones levels were affected by dietary treatment (p < 0.01). From our findings, it could be effective to include air-classified SFM in early-phase laying hen diets as an alternative protein source substituting SBM, without negative influence on productive performance and egg traits, reducing also the production costs.

  17. Dietary levels of chia: influence on hen weight, egg production and sensory quality, for two strains of hens.

    Science.gov (United States)

    Ayerza, R; Coates, W

    2002-05-01

    1. Laying hens, 225 white and 225 brown, were fed for 90 d to compare a control diet with diets containing 70, 140, 210 and 280 g/kg chia (Salvia hispanica L.) seed. 2. Hen weight was not significantly affected by diet; however, manure production was less for the hens fed on chia. 3. Egg weight and production, yolk weight, and yolk percentage were determined at d 0, 30, 43, 58, 72 and 90. 4. A sensory evaluation was conducted on eggs produced during the last week of the trial. 5. No significant differences in egg production were found among treatments for the brown hens. 6. With the 280 g/kg chia diet, the white hens produced fewer and lighter eggs than did the hens fed on the control diet. 7. No significant differences were detected in yolk weight until d 90. 8. On this date the yolks produced by the white hens fed on the 70 g/kg chia diet were significantly lighter in weight, whereas the brown hens produced significantly heavier yolks, compared with the hens fed on the control diet. 9. Yolk weight as a percentage of egg weight was lower for white hens throughout the trial except on d 58 with the 140 g/kg chia diet. Significant differences, however, were detected only with the 70 g/ kg chia diet on d 90 and with the 210 g/kg chia diet on d 58, 72 and 90. 10. No significant differences in taste preference or flavour were found among any of the chia treatments and the control.

  18. Modeling disordered regions in proteins using Rosetta.

    Directory of Open Access Journals (Sweden)

    Ray Yu-Ruei Wang

    Full Text Available Protein structure prediction methods such as Rosetta search for the lowest energy conformation of the polypeptide chain. However, the experimentally observed native state is at a minimum of the free energy, rather than the energy. The neglect of the missing configurational entropy contribution to the free energy can be partially justified by the assumption that the entropies of alternative folded states, while very much less than unfolded states, are not too different from one another, and hence can be to a first approximation neglected when searching for the lowest free energy state. The shortcomings of current structure prediction methods may be due in part to the breakdown of this assumption. Particularly problematic are proteins with significant disordered regions which do not populate single low energy conformations even in the native state. We describe two approaches within the Rosetta structure modeling methodology for treating such regions. The first does not require advance knowledge of the regions likely to be disordered; instead these are identified by minimizing a simple free energy function used previously to model protein folding landscapes and transition states. In this model, residues can be either completely ordered or completely disordered; they are considered disordered if the gain in entropy outweighs the loss of favorable energetic interactions with the rest of the protein chain. The second approach requires identification in advance of the disordered regions either from sequence alone using for example the DISOPRED server or from experimental data such as NMR chemical shifts. During Rosetta structure prediction calculations the disordered regions make only unfavorable repulsive contributions to the total energy. We find that the second approach has greater practical utility and illustrate this with examples from de novo structure prediction, NMR structure calculation, and comparative modeling.

  19. Transgenic chickens as bioreactors for protein-based drugs.

    Science.gov (United States)

    Lillico, Simon G; McGrew, Michael J; Sherman, Adrian; Sang, Helen M

    2005-02-01

    The potential of using transgenic animals for the synthesis of therapeutic proteins was suggested over twenty years ago. Considerable progress has been made in developing methods for the production of transgenic animals and specifically in the expression of therapeutic proteins in the mammary glands of cows, sheep and goats. Development of transgenic hens for protein production in eggs has lagged behind these systems. The positive features associated with the use of the chicken in terms of cost, speed of development of a production flock and potentially appropriate glycosylation of target proteins have led to significant advances in transgenic chicken models in the past few years.

  20. Air quality measurements in laying hens housing

    Directory of Open Access Journals (Sweden)

    Mirko Prodanov

    2016-03-01

    Full Text Available Ensuring good environmental conditions of the poultry houses can be costly for the farmers, but without it losses due to poor bird health and performance due to poor air quality can be much more detrimental to net returns. The goal of this study was to investigate the variations in air quality in various areas inside the laying hen houses. Ten houses with laying hen conventional battery cages were measured for O2, H2S, CO, NH3, temperature, relative humidity, CO2, airflow and luminance. The results of the physical measures showed that temperatures in the houses were between 15.31–25.6°C, the relative humidity 48.03-81.12%, while the luminance rarely exceeded 8 lux. As for the gasses, the values for NH3 rarely exceeded 8 ppm, although at some measuring points it reached 26 ppm. O2 was generally at 20.9 %, and the levels of CO2 were very low. No presence of H2S and CO was detected. In this study it was concluded that the measurement of the air quality in a house can vary depending of the places this measures are taken. Multiple measurement points are important because they may make the staff aware of the problems connected to low ventilation and culmination of harmful gases. The air quality in different positions in the houses is of great importance not only for the animal welfare, but also for the safety of the staff.

  1. Welfare issues of modern laying hen farming

    Directory of Open Access Journals (Sweden)

    Valentina Ferrante

    2010-01-01

    Full Text Available This review starts with a brief outline of poultry behaviour and biology and a description of the present laying hen farming situation in Italy. Moreover, it points out the situation of EU legislation currently in effect for laying hen welfare. It then reviews the main welfare issues of layer farming. The following aspects are considered: rearing system (e.g. stocking density, light intensity and photoperiod, equipment and facilities and some health aspects. All these aspects represent important issues for farmed species, but special attention should be paid when we deal with intensively farmed species like poultry, where a lot of potential stressors may impair the welfare with consequences on health and production. The adoption of suitable housing systems and of adequate management techniques, as well as the presence of well trained stockpersons with a sound knowledge of poultry physiology and behaviour, are particularly important in guaranteeing a sufficient welfare level to poultry. Therefore, the adoption of specific codes of recommendations is highly desirable.

  2. Reproductive performance of artificially inseminated hens receiving saline drinking water.

    Science.gov (United States)

    Zhang, D; Moreng, R E; Balnave, D

    1991-04-01

    Laying hens were selected at random and placed in individual cages in a commercial type layer shed. One hundred hens received town water and one hundred received town water supplemented with 2 g NaCl/L. Half the hens on each water treatment were inseminated every 7 days with mixed semen collected from six cockerels of a commercial table egg strain maintained on town water. The remaining hens were inseminated with semen from six cockerels receiving town water supplemented with 2 g NaCl/L. Eggs were collected and stored at 12 C over a 7-day period before eggs with defective shells were identified and removed. All remaining eggs were incubated and candled at 7 and 18 days of incubation to detect infertile eggs and embryonic deaths. Data from six consecutive hatches were analyzed. The incidence of eggs with defective shells doubled in hens receiving the saline drinking water. These hens had a significantly (twofold) higher incidence of embryonic deaths and a significantly lower (13%) hatchability of fertile eggs. For every 100 eggs laid the numbers of settable eggs and chicks hatched were significantly reduced in hens receiving the saline drinking water. The saline water reduced the numbers hatched by 20% for every 100 eggs laid. The water treatment given to the cockerels had little effect on reproductive performance.

  3. Comparison of extraction conditions for milk and hen's egg allergens.

    Science.gov (United States)

    Steinhoff, M; Fischer, M; Paschke-Kratzin, A

    2011-04-01

    The evaluation of recovery rates by extracting milk powder and egg powder using eleven different extractants gave approximately similar results for both foods. Compared with the other extraction solutions investigated, '1% Tween 20® and 0.4% Triton X-100®' and '4% SDS' are the most suitable extractants to isolate proteins of hen's egg or milk. When comparing calculated protein recovery rates of egg and milk powder extracts, the results clearly indicated that the choice of a suitable extractant is of particular importance. Qualitative investigation of the extracts via LDS-PAGE followed by silver staining as well as immunoblotting confirmed the results of protein quantification. Hence, the immunoblots showed that the extraction agents had no negative influence on the antigenicity of the extracted allergenic proteins. In this study, variation of extraction temperature led neither to any benefit in extraction quality nor to degradation. Changing pH did not reveal any trends, but progressive protein hydrolysis under strong alkaline conditions. Evaluation of recovery rates as well as results of unspecific and specific staining of the extracts showed that an extraction time of 1 h is sufficient for an appropriate sample preparation. For investigations with and without food matrix different results were obtained. In summary, wheat starch did not influence the extraction quality within all examined materials and different extractants. In contrast, using fat powder and dry cake mix, respectively, led to different results in the extraction procedure. When fat powder and dry cake mix were used as food matrices, some protein recovery rates decreased and some increased depending on the allergen material. These results highlight the fact that the suitability of the extractant not only depends on the properties of the allergen but furthermore on the type of matrix containing the allergen.

  4. Housing conditions alter properties of the tibia and humerus during the laying phase in Lohmann white Leghorn hens.

    Science.gov (United States)

    Regmi, P; Smith, N; Nelson, N; Haut, R C; Orth, M W; Karcher, D M

    2016-01-01

    Osteoporosis in caged hens is one driving factor for the United States egg industry to explore options regarding alternative housing systems for laying hens. The aim of our research was to study the influence of housing systems on tibiae and humeri of 77-week-old Lohmann White hens. Pullets raised in an aviary system were either continued in aviary hen systems (AV) or conventional cages (AC) whereas pullets reared in conventional cages continued in conventional hen cages (CC) or enriched colony cages (EN) at 19 weeks. From each group, 120 hens were randomly euthanized and right and left tibae and humeri were excised for structural and mechanical analysis. Volumetric density of the cortical bone was measured using quantitative computed tomography (QCT). Aviary (AV) hens had greater cortical thickness and density but similar outer dimensions to AC hens (P Hens in EN system had humeri with similar cortical thickness and density but wider outer dimensions than the humeri of CC hens (P hens, whereas EN hens had denser tibial cortex than CC hens (P hens in the AV system were better able to protect their structure from endosteal resorption during the laying phase. Humeri of AV and EN hens had increased second moment of area compared to the AC and CC hens; however, the changes were not observed in tibiae. Mechanical property differences were observed, with bones of AV hens having greater failure moment and stiffness than AC hens and the same difference was observed between the EN and CC hens, (P hens.

  5. Modelling heating effects in cryocooled protein crystals

    CERN Document Server

    Nicholson, J; Fayz, K; Fell, B; Garman, E

    2001-01-01

    With the application of intense X-ray beams from third generation synchrotron sources, damage to cryocooled macromolecular crystals is being observed more commonly . In order to fully utilize synchrotron facilities now available for studying biological crystals, it is essential to understand the processes involved in radiation damage and beam heating so that, if possible, action can be taken to slow the rate of damage. Finite Element Analysis (FEA) has been applied to model the heating effects of X-rays on cryocooled protein crystals, and to compare the relative cooling efficiencies of nitrogen and helium.

  6. Characterization of the surface of protein-adsorbed dental materials by wetting and streaming potential measurements

    NARCIS (Netherlands)

    Matsumura, H.; Kawasaki, K.; Okumura, N.; Kambara, M.; Norde, W.

    2003-01-01

    In this study we have elucidated the water-wettability and the electrokinetic surface potential of protein-covered dental materials. The proteins used here as typical proteins were human serum albumin and lysozyme from hen*s egg. The wettability (hydrophobicity/hydrophilicity) and the surface potent

  7. Minimalist models for proteins: a comparative analysis.

    Science.gov (United States)

    Tozzini, Valentina

    2010-08-01

    The last decade has witnessed a renewed interest in the coarse-grained (CG) models for biopolymers, also stimulated by the needs of modern molecular biology, dealing with nano- to micro-sized bio-molecular systems and larger than microsecond timescale. This combination of size and timescale is, in fact, hard to access by atomic-based simulations. Coarse graining the system is a route to be followed to overcome these limits, but the ways of practically implementing it are many and different, making the landscape of CG models very vast and complex. In this paper, the CG models are reviewed and their features, applications and performances compared. This analysis, restricted to proteins, focuses on the minimalist models, namely those reducing at minimum the number of degrees of freedom without losing the possibility of explicitly describing the secondary structures. This class includes models using a single or a few interacting centers (beads) for each amino acid. From this analysis several issues emerge. The difficulty in building these models resides in the need for combining transferability/predictive power with the capability of accurately reproducing the structures. It is shown that these aspects could be optimized by accurately choosing the force field (FF) terms and functional forms, and combining different parameterization procedures. In addition, in spite of the variety of the minimalist models, regularities can be found in the parameters values and in FF terms. These are outlined and schematically presented with the aid of a generic phase diagram of the polypeptide in the parameter space and, hopefully, could serve as guidelines for the development of minimalist models incorporating the maximum possible level of predictive power and structural accuracy.

  8. Henning Witte : Estonia-film tuleb / Villem Valme

    Index Scriptorium Estoniae

    Valme, Villem, 1977-

    2000-01-01

    Kavandatavast katastrooffilmist "Baltic Storm", mis on ajendatud väidetest, et "Estonia" uppus maffiavandenõu tõttu. Stsenaristideks on Juta Rabe, Henning Witte ja Kaj Holmberg. Ka : Nädal nr. 47, lk. 5

  9. Performance of an image analysis processing system for hen tracking in an environmental preference chamber.

    Science.gov (United States)

    Kashiha, Mohammad Amin; Green, Angela R; Sales, Tatiana Glogerley; Bahr, Claudia; Berckmans, Daniel; Gates, Richard S

    2014-10-01

    Image processing systems have been widely used in monitoring livestock for many applications, including identification, tracking, behavior analysis, occupancy rates, and activity calculations. The primary goal of this work was to quantify image processing performance when monitoring laying hens by comparing length of stay in each compartment as detected by the image processing system with the actual occurrences registered by human observations. In this work, an image processing system was implemented and evaluated for use in an environmental animal preference chamber to detect hen navigation between 4 compartments of the chamber. One camera was installed above each compartment to produce top-view images of the whole compartment. An ellipse-fitting model was applied to captured images to detect whether the hen was present in a compartment. During a choice-test study, mean ± SD success detection rates of 95.9 ± 2.6% were achieved when considering total duration of compartment occupancy. These results suggest that the image processing system is currently suitable for determining the response measures for assessing environmental choices. Moreover, the image processing system offered a comprehensive analysis of occupancy while substantially reducing data processing time compared with the time-intensive alternative of manual video analysis. The above technique was used to monitor ammonia aversion in the chamber. As a preliminary pilot study, different levels of ammonia were applied to different compartments while hens were allowed to navigate between compartments. Using the automated monitor tool to assess occupancy, a negative trend of compartment occupancy with ammonia level was revealed, though further examination is needed.

  10. Factors influencing wild turkey hen survival in southcentral Iowa

    Science.gov (United States)

    Hubbard, M.W.; Garner, D.L.; Klaas, E.E.

    1999-01-01

    A decline in the population of eastern wild turkeys (Meleagris gallopavo silvestris) in southcentral Iowa necessitated more current estimates of population parameters. Survival of 126 eastern wild turkey hens in southcentral Iowa was investigated during 1993-96. Estimates of annual survival averaged 0.676 ?? 0.048% (x?? ?? SE) for adults and 0.713 ?? 0.125 for subadults. Mammalian predators, primarily coyotes (Canis latrans) and red fox (Vulpes fulva) accounted for 64% of all documented mortality. Age-specific annual survival distributions differed within years (P < 0.03), but no difference was detected in survival between age classes across years (P = 0.49). Based on chronological dates, survival of adult hens differed among seasons across years (P = 0.03). However, seasonal survival was not different when estimates were based on hen behavior (p = 0.48). Risk of mortality for hens increased by 2.0% for every 100-m increase in dispersal distance, decreased by 2.0% for every 10-ha increase in home range size, and decreased by 3.5% for each 1.0% increase in proportion of home range in woody cover. Although the exact cause of the population decline remains unknown, we suggest it was more likely related to a decrease in production than changes in hen survival. Declining turkey populations would likely benefit more from management designed to increase reproduction rather than hen survival.

  11. Efficacy of fertilization in artificially inseminated turkey hens.

    Science.gov (United States)

    Christensen, V L; Bagley, L G

    1989-05-01

    Research was conducted to develop an artificial insemination protocol optimizing the use of spermatozoa by turkey breeder hens. Large White turkey hens were inseminated on Days 14 and 17 postphotostimulation with 200 million spermatozoa from one male phenotype to fill the oviductal storage sites. Artificial inseminations were then performed weekly for 20 wk with different spermatozoa numbers of another male phenotype. Fertility and phenotype of each poult were determined at hatch to ascertain which insemination, initial or subsequent, was responsible for fertility. Inseminating weekly with 200 million viable spermatozoa cells resulted in better fertility but did not optimize the hen's utilization of spermatozoa from the initial inseminations. When fewer spermatozoa were inseminated weekly (50 million cells), more progeny were fertilized by spermatozoa already residing in the oviduct than would be expected. When the number of spermatozoa inseminated weekly was increased at intervals during a laying cycle, spermatozoa from the initial inseminations were utilized more efficiently, but fertility was depressed at times during the laying cycle. Gradually increasing weekly inseminated numbers of spermatozoa from 50 to 200 million viable cells/hen as the hens age results in nearly equivalent fertility to that resulting from insemination by 200 million cells each week. This represents a savings of 1.4 billion spermatozoa/hen over a 20-wk laying period.

  12. Mining protein kinases regulation using graphical models.

    Science.gov (United States)

    Chen, Qingfeng; Chen, Yi-Ping Phoebe

    2011-03-01

    Abnormal kinase activity is a frequent cause of diseases, which makes kinases a promising pharmacological target. Thus, it is critical to identify the characteristics of protein kinases regulation by studying the activation and inhibition of kinase subunits in response to varied stimuli. Bayesian network (BN) is a formalism for probabilistic reasoning that has been widely used for learning dependency models. However, for high-dimensional discrete random vectors the set of plausible models becomes large and a full comparison of all the posterior probabilities related to the competing models becomes infeasible. A solution to this problem is based on the Markov Chain Monte Carlo (MCMC) method. This paper proposes a BN-based framework to discover the dependency correlations of kinase regulation. Our approach is to apply the MCMC method to generate a sequence of samples from a probability distribution, by which to approximate the distribution. The frequent connections (edges) are identified from the obtained sampling graphical models. Our results point to a number of novel candidate regulation patterns that are interesting in biology and include inferred associations that were unknown.

  13. Evolution and physics in comparative protein structure modeling.

    Science.gov (United States)

    Fiser, András; Feig, Michael; Brooks, Charles L; Sali, Andrej

    2002-06-01

    From a physical perspective, the native structure of a protein is a consequence of physical forces acting on the protein and solvent atoms during the folding process. From a biological perspective, the native structure of proteins is a result of evolution over millions of years. Correspondingly, there are two types of protein structure prediction methods, de novo prediction and comparative modeling. We review comparative protein structure modeling and discuss the incorporation of physical considerations into the modeling process. A good starting point for achieving this aim is provided by comparative modeling by satisfaction of spatial restraints. Incorporation of physical considerations is illustrated by an inclusion of solvation effects into the modeling of loops.

  14. EGG QUALITY AND HATCHABILITY OF In situ - REARED KEDU AND CEMANI HENS FED DIET OF FARMER FORMULATION SUPPLEMENTED WITH VITAMIN E

    Directory of Open Access Journals (Sweden)

    H.I. Wahyuni

    2014-10-01

    Full Text Available The aim of study was to evaluate the effect of dietary vitamin E supplementation in Kedu andCemani hens reraed in situ and given farmer-formulated diet on egg performances. A total of 120 femaleand 24 male birds were equally divided into two groups of Kedu and Cemani, with average body weightof 1890+216.79 and 1830+396.23 g, respectively. Basal ration was based on the diet formulated by thefarmer (R1 consisting of corn (30%, rice bran (50%, protein concentrate (15%, and premix (5%.Dietary treatments evaluated were R1 (without additional vitamin E, and the other three were theinclusion of DL α-tocopheryl acetate into the R1 diet up to 2 (R2, 4 (R3 and 6 IU (R4. The experimentwas arranged in a Randomized Block Design with 4 treatments, and 2 different groups of hen (Kedu andCemani were assigned as block. Parameters observed were feed consumption, hen day production, feedconversion ratio, egg quality, fertility, and hatchability. The result showed that vitamin Esupplementation did not affect whatever parameters, except egg fertility. Egg hatchability between Keduand Cemani hens was significantly different (p<0.05. Trend comparison test indicated significantlylinear (p<0.05 for fertility and hatchability. In conclusion, vitamin E supplementation up to 6 IUincreased linearly egg fertility and hatchability of about 5-8%, and egg hatchability of Kedu hens washigher (11% than that of Cemani.

  15. EGG QUALITY AND HATCHABILITY OF In situ - REARED KEDU AND CEMANI HENS FED DIET OF FARMER FORMULATION SUPPLEMENTED WITH VITAMIN E

    Directory of Open Access Journals (Sweden)

    H. I. Wahyuni

    2011-03-01

    Full Text Available The aim of study was to evaluate the effect of dietary vitamin E supplementation in Kedu and Cemani hens reraed in situ and given farmer-formulated diet on egg performances. A total of 120 female and 24 male birds were equally divided into two groups of Kedu and Cemani, with average body weight of 1890+216.79 and 1830+396.23 g, respectively. Basal ration was based on the diet formulated by the farmer (R1 consisting of corn (30%, rice bran (50%, protein concentrate (15%, and premix (5%. Dietary treatments evaluated were R1 (without additional vitamin E, and the other three were the inclusion of DL α-tocopheryl acetate into the R1 diet up to 2 (R2, 4 (R3 and 6 IU (R4. The experiment was arranged in a Randomized Block Design with 4 treatments, and 2 different groups of hen (Kedu and Cemani were assigned as block. Parameters observed were feed consumption, hen day production, feed conversion ratio, egg quality, fertility, and hatchability. The result showed that vitamin E supplementation did not affect whatever parameters, except egg fertility. Egg hatchability between Kedu and Cemani hens was significantly different (p<0.05. Trend comparison test indicated significantly linear (p<0.05 for fertility and hatchability. In conclusion, vitamin E supplementation up to 6 IU increased linearly egg fertility and hatchability of about 5-8%, and egg hatchability of Kedu hens was higher (11% than that of Cemani.

  16. Equação de predição da exigência de proteína bruta para aves reprodutoras pesadas na fase de produção Prediction equation of crude protein requirements for broiler breeders hens

    Directory of Open Access Journals (Sweden)

    Carlos Bôa-Viagem Rabello

    2002-06-01

    Full Text Available O objetivo do presente trabalho foi determinar as exigências de proteína para aves reprodutoras pesadas através do método fatorial. A exigência de proteína bruta para mantença (PBm foi determinada por intermédio da técnica do balanço de nitrogênio por meio de ensaio de metabolismo com aves submetidas a quatro dietas com níveis decrescentes de proteína, proporcionando balanço positivo, próximo a zero e negativo. Para determinar a exigência de proteína bruta para o ganho de peso (PBg dois experimentos foram conduzidos, sendo que em um, determinou-se as exigências líquidas de nitrogênio e no outro, a eficiência de utilização do nitrogênio para o ganho, por meio de abates semanais de aves no período de 26 a 33 semanas de idade. A exigência de proteína bruta para produção de ovos (PBo foi determinada através de análises semanais de proteína bruta dos ovos coletados, no período de 31 a 37 semanas de idade, considerando a eficiência de deposição da proteína no ovo. A exigência e eficiência de utilização da proteína para mantença foram 2.282 mg PB/kg0,75/dia e 60,79%; respectivamente. As exigências de PBg e PBo determinadas foram: 356 mg PB/g e 262 mg PB/g, respectivamente, e as eficiências de utilização do nitrogênio, 40 e 46,80%, respectivamente. A equação de predição elaborada para aves reprodutoras pesadas na fase de produção foi: PB=2,282.P0,75+0,356.G+0,262.MO, onde PB é a exigência de proteína bruta (g/ave/dia, P o peso corporal (kg, G o ganho de peso (g/dia e MO a massa de ovos (g/dia.The objective of this study was to determine the protein requirement for broiler breeder hens using factorial method. The requirement of crude protein for maintenance (CPm was determined using nitrogen balance technique in metabolism assay. The birds were fed with four protein levels in order to get a positive, a close to zero and a negative nitrogen balance. To determine the crude protein weight gain

  17. Simple micromechanical model of protein crystals for their mechanical characterizations

    Directory of Open Access Journals (Sweden)

    Na S.

    2010-06-01

    Full Text Available Proteins have been known to perform the excellent mechanical functions and exhibit the remarkable mechanical properties such as high fracture toughness in spider silk protein [1]. This indicates that the mechanical characterization of protein molecules and/or crystals is very essential to understand such remarkable mechanical function of protein molecules. In this study, for gaining insight into mechanical behavior of protein crystals, we developed the micromechanical model by using the empirical potential field prescribed to alpha carbon atoms of a protein crystal in a unit cell. We consider the simple protein crystals for their mechanical behavior under tensile loading to be compared with full atomic models

  18. Towards a model for protein production rates

    CERN Document Server

    Dong, J J; Zia, R K P

    2007-01-01

    In the process of translation, ribosomes read the genetic code on an mRNA and assemble the corresponding polypeptide chain. The ribosomes perform discrete directed motion which is well modeled by a totally asymmetric simple exclusion process (TASEP) with open boundaries. Using Monte Carlo simulations and a simple mean-field theory, we discuss the effect of one or two ``bottlenecks'' (i.e., slow codons) on the production rate of the final protein. Confirming and extending previous work by Chou and Lakatos, we find that the location and spacing of the slow codons can affect the production rate quite dramatically. In particular, we observe a novel ``edge'' effect, i.e., an interaction of a single slow codon with the system boundary. We focus in detail on ribosome density profiles and provide a simple explanation for the length scale which controls the range of these interactions.

  19. Towards a Model for Protein Production Rates

    Science.gov (United States)

    Dong, J. J.; Schmittmann, B.; Zia, R. K. P.

    2007-07-01

    In the process of translation, ribosomes read the genetic code on an mRNA and assemble the corresponding polypeptide chain. The ribosomes perform discrete directed motion which is well modeled by a totally asymmetric simple exclusion process (TASEP) with open boundaries. Using Monte Carlo simulations and a simple mean-field theory, we discuss the effect of one or two "bottlenecks" (i.e., slow codons) on the production rate of the final protein. Confirming and extending previous work by Chou and Lakatos, we find that the location and spacing of the slow codons can affect the production rate quite dramatically. In particular, we observe a novel "edge" effect, i.e., an interaction of a single slow codon with the system boundary. We focus in detail on ribosome density profiles and provide a simple explanation for the length scale which controls the range of these interactions.

  20. Ochratoxicosis in White Leghorn breeder hens: Production and breeding performance

    Directory of Open Access Journals (Sweden)

    Zahoor Ul Hassan*, Muhammad Zargham Khan, Ahrar Khan, Ijaz Javed1, Umer Sadique2 and Aisha Khatoon

    2012-10-01

    Full Text Available This study was designed to evaluate the effect of Ochratoxin A (OTA upon production and breeding parameters in White Leghorn (WL breeder hens. For this purpose, 84 WL breeder hens were divided into seven groups (A-G. The hens in these groups were maintained on feed contaminated with OTA @ 0.0 (control, 0.1, 0.5, 1.0, 3.0, 5.0 and 10.0 mg/Kg, respectively for 21 days. These hens were artificially inseminated with semen obtained from healthy roosters kept on OTA free feed. Egg production and their quality parameters were recorded. Fertile eggs obtained from each group were set for incubation on weekly basis. At the end of the experiment, hens in each group were killed to determined gross and microscopic lesions in different organs. OTA residue concentrations were determined in extracts of liver, kidneys and breast muscles by immunoaffinity column elution and HPLC-Fluorescent detection techniques. Feeing OTA contaminated diet resulted in a significant decrease in egg mass and egg quality parameters. Liver and kidneys showed characteristic lesions of ochratoxicosis. Residue concentration (ng/g of OTA in the hens fed 10 mg/kg OTA, was the highest in liver (26.336±1.16 followed by kidney (8.223±0.85 and were least in breast muscles (1.235±0.21. Embryonic mortalites were higher, while hatachabilites of the chicks were lower in the groups fed higher doses of OTA. Feeding OTA contaminated diets to breeder hen resulted in residues accumulation in their tissues along with significantly reduced production and breeding performance.

  1. Nutrients and Cholesterol of Eggs Affected by Dried Tomato Meal in Laying Hens Diet

    Directory of Open Access Journals (Sweden)

    Jein R. Leke

    2015-01-01

    Full Text Available One hundred MB 402 laying hens (36 weeks of age were used for the study. The birds were divided into five experimental diets and each was divided into four replicate groups of five birds per replicate. The control diet (based diet was formulated to contain 51% corn, 14% rice bran, 7% fish meal, 6% CaCO3, and 22% commercial diet. Tomato meal was included in four experimental diets at levels of 2, 4, 6, 8% to substitute based diet. The treatments were: R0 = 100% based diet (BD + 0% tomato meal (TM; R1 = 98% BD + 2% TM; R2 = 96% BD + 4% TM; R3 = 94% BD + 6% TM; and R4 = 92% BD + 8% TM. Chemical composition of tomato meal were: 16.73% crude protein, 1.53% fat, 30.94% crude fiber, 0.98% Ca, 1.20% P, and 2416 Kcal/kg ME. Feed and water were provided for ad libitum. The study was conducted over a period of 8 weeks, and data were collected on nutrients of eggs: crude protein, fat, carbohydrate, and cholesterol of eggs. Proximate analysis eggs was determined by the methods of AOAC (1990, and cholesterol was determined by Libermann and Burchad method. Data were analyzed by one-way analysis of variance (ANOVA. The treatment means were compared using Duncan’s multiple range test. The results showedthat no differences in hen egg nutrients and cholesterol between treatments R1, R2, R3, and R4 compared to treatment R0 (control. It can be concluded that tomato meal can be used as an alternative feedstuff in laying hen diets to substitute based diet, at inclusion levels up to 8% without negative effects on egg quality.

  2. Genetic analysis of body size traits of 13-week-old hens using a mixed model considering major gene and polygene%13周龄母鸡体尺性状主基因+多基因混合遗传模型分析

    Institute of Scientific and Technical Information of China (English)

    马猛; 王克华; 曲亮; 窦套存; 沈曼曼; 郭军; 卢建; 胡玉萍

    2015-01-01

    研究以绿壳蛋鸡黑羽纯系和白来航鸡为对象构建分离群体,测定亲本P1、P2、F1和F2代母鸡13周龄体尺,运用主基因+多基因混合遗传分析软件SEA-G4F2对分离群体13周龄体尺性状进行遗传分析.结果表明,母鸡13周龄胫围、胫长、龙骨长、体斜长和胸宽的最适模型均为E模型,即两对加性-显性-上位性主基因+加性-显性-上位性多基因混合遗传模型,主基因遗传率分别为33.58%、25.74%、27.02%、24.92%和33.72%,龙骨长、体斜长和胸宽的多基因遗传率为1.13%、1.71%和4.61%;13周龄胸角最适模型为E-1,即两对加性-显性-上位性主基因+加性-显性多基因混合遗传模型,主基因遗传率为55.06%.胫围、胫长和胸角多基因遗传率均为0,各个性状主基因遗传效应均大于多基因遗传效应.%In this study, green-eggshel layer black feather pure lines and White Leghorn acted as par-ents to constructed segregating population, body size traits of hens at 13-week-old of P1, P2, F1 and F2 were measured, the analysis software of major gene and polygene mixed inheritance model in the hens body size traits was SEA-G4F2. The results showed that the best model of shank girth, shank length, keel length, body slanting length and chest width of hens at 13-week-old was model E, namely two pairs of additive-domi-nance-epistatic major gene plus additive-dominance-epistatic polygene mixed genetic model, their heritability of major gene were 33.58%, 25.74%, 27.02%, 24.92%and 33.72%, respectively, the heritablity of polygene in keel length, body slanting length and chest width were 1.13%, 1.71%and 4.61%, respectively;the best mod-el of chest angle was model E-1, which named two pairs of additive-dominance-epistatic major gene plus addi-tive-dominance polygene mixed genetic model, the heritability of major gene was 55.06%. the polygene heri-tability of shank girth, shank length and chest angle were 0, major gene has a bigger genetic effect than

  3. Knowledge of Chemical Indicators of Eggs from Hens Reared in Conventional and Free Range System

    Directory of Open Access Journals (Sweden)

    Lucia Iuliana Cotfas

    2014-11-01

    Full Text Available Introduction Many consumers prefer nowadays eggs from alternative production systems because of their concerns about its own food safety and welfare of laying hens (Anderson. K. E., 2009. According to the regulations, a free range egg is obtained in poultry farms were laying hens have access to outdoor paddock, where they can show all the instincts of physiological and ethological (Usturoi M.G., 2004. Aims: The aim of this research was the correct information on the quality of these products and comparative study of chemical characteristics of eggs obtain from different production systems (conventional and free range. Materials and Methods: Chemical indicators’ determination was made through specific methods, in according with actual standards and consists in establishing of water, proteins, fats, ash and non-nitrogenous extractive substances contents. The biological material was represented by 90 eggs produced by Lohmann Brown laying hens aged 33 weeks: 45 gathered from birds exploited in free range system and 45 from birds reared in cages agreed by EU. Results: Egg obtained from free range system have a slightly higher content of protein (10.35±0.12 % vs. 9.97±0.03 % compared with conventional system, from albumen and from yolk (17.46±0.00 % vs. 17.19±0.01 %, this fact was happened because of aport of green grass from the outside paddock (Morris T.R., 2004. Comparative with conventional system, eggs from free range system have a higher content of lipids of yolk with 2.23%.Chemical analysis of melange from studied eggs showed a higher rate of dry matter at free range eggs (23.374% vs. 22.969%, but also for proteins (12.952% vs. 12.520% and lipids (7.676% vs. 7.398%. Conclusions: The increase in freedom of laying hens (free range caused a qualitative improvement of dry components of both the egg components (yolk and albumen but also the quantitative one, and eggs obtained has a high nutritional value  

  4. Genomic prediction of survival time in a population of brown laying hens showing cannibalistic behavior.

    Science.gov (United States)

    Alemu, Setegn W; Calus, Mario P L; Muir, William M; Peeters, Katrijn; Vereijken, Addie; Bijma, Piter

    2016-09-13

    Mortality due to cannibalism causes both economic and welfare problems in laying hens. To limit mortality due to cannibalism, laying hens are often beak-trimmed, which is undesirable for animal welfare reasons. Genetic selection is an alternative strategy to increase survival and is more efficient by taking heritable variation that originates from social interactions into account, which are modelled as the so-called indirect genetic effects (IGE). Despite the considerable heritable variation in survival time due to IGE, genetic improvement of survival time in laying hens is still challenging because the detected heritable variation of the trait with IGE is still limited, ranging from 0.06 to 0.26, and individuals that are still alive at the end of the recording period are censored. Furthermore, survival time records are available late in life and only on females. To cope with these challenges, we tested the hypothesis that genomic prediction increases the accuracy of estimated breeding values (EBV) compared to parental average EBV, and increases response to selection for survival time compared to a traditional breeding scheme. We tested this hypothesis in two lines of brown layers with intact beaks, which show cannibalism, and also the hypothesis that the rate of inbreeding per year is lower for genomic selection than for the traditional breeding scheme. The standard deviation of genomic prediction EBV for survival time was around 22 days for both lines, indicating good prospects for selection against mortality in laying hens with intact beaks. Genomic prediction increased the accuracy of the EBV by 35 and 32 % compared to the parent average EBV for the two lines. At the current reference population size, predicted response to selection was 91 % higher when using genomic selection than with the traditional breeding scheme, as a result of a shorter generation interval in males and greater accuracy of selection in females. The predicted rate of inbreeding per

  5. A modified resonant recognition model to predict protein-protein interaction

    Institute of Scientific and Technical Information of China (English)

    LIU Xiang; WANG Yifei

    2007-01-01

    Proteins are fundamental components of all living cells and the protein-protein interaction plays an important role in vital movement.This paper briefly introduced the original Resonant Recognition Model (RRM),and then modified it by using the wavelet transform to acquire the Modified Resonant Recognition Model (MRRM).The key characteristic of the new model is that it can predict directly the proteinprotein interaction from the primary sequence,and the MRRM is more suitable than the RRM for this prediction.The results of numerical experiments show that the MRRM is effective for predicting the protein-protein interaction.

  6. 40周龄母鸡体尺性状的主基因+多基因混合遗传分析%Inheritance of 40-week-old hens body size traits using major gene and pol-ygene mixed model

    Institute of Scientific and Technical Information of China (English)

    马猛; 王克华; 曲亮; 窦套存; 沈曼曼

    2015-01-01

    Black-feathered line of green-shelled laying hens( P1 ) , while leghorn chickens( P2 ) , and the 40-week-old hens of the segregating populations( F1 , F2 ) were measured for the body sizes traits to study the inheritance of body size using major gene plus polygene mixed model. Model E-1 , a two-pair additive-dominance-epistatic major gene plus additive-dominance polygene mixed genetic model fitted the best for shank girth, shank length, chest angle and chest width of hens at 40-week-old, with the heritabilities of major gene being 60. 89%, 61. 24%, 55. 62% and 59. 43%, respectively. The best model for keel length and body slanting length was model E, a two-pair additive-dominance-epistatic majorgene plus additive-dominance-epistatic polygene mixed genetic model, with the heritabilities of major gene being 16. 52% and 30. 76%, and the heritability of polygene for keel length being 7. 2%. The poly-gene heritablity in six body size traits was not detected except for keel length, and the genetic efficiency of major genes is greater than polygenes.%为研究40周龄母鸡体尺性状的内在遗传机理,以绿壳蛋鸡黑羽纯系和白来航鸡为对象构建分离群体,测定亲本(P1、P2)、F1代和F2代母鸡40周龄的体尺,运用主基因+多基因混合遗传分析软件SEA-G4F2对分离群体40周龄体尺性状进行遗传分析。结果表明:母鸡40周龄的胫围、胫长、胸角和胸宽的最适模型均为E-1,即2对加性-显性-上位性主基因+加性-显性多基因混合遗传模型,其对应的主基因的遗传率分别为60.89%、61.24%、55.62%和59.43%;龙骨长和体斜长的最适模型均为E模型,即2对加性-显性-上位性主基因+加性-显性-上位性多基因混合遗传模型,主基因遗传率为16.52%和30.76%,龙骨长对应的多基因的遗传率为7.2%。6个体尺性状中除了龙骨长检测出多基因外,其他性状均未检测到多基因,各个性状的主基因的遗传效应均大于多基因的遗传效应。

  7. The effect of perch availability during pullet rearing and egg laying on the behavior of caged White Leghorn hens.

    Science.gov (United States)

    Hester, P Y; Garner, J P; Enneking, S A; Cheng, H W; Einstein, M E

    2014-10-01

    Enriched cages, compared with conventional cages, allow egg laying strains of chickens to meet some behavioral needs, including a high motivation to perch. The objective of this study was to determine if perch availability during rearing affected perch use as adults and if perch presence affected eating and drinking in caged White Leghorn hens. Chickens were assigned to 14 cages each with and without 2 round metal perches from hatch to 16.9 wk of age. At 17 wk of age, pullets were assigned to laying cages consisting of 1 of 4 treatments. Treatment 1 chickens never had access to perches (controls). Treatment 2 chickens only had access to 2 round metal perches during the laying phase (17 to 71 wk of age). Treatment 3 chickens only had access to 2 round perches during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens had access to the perches during both the pullet and laying phase. Each treatment during the adult phase consisted of 9 cages with 9 birds/cage for a total of 36 cages. Automatic infrared cameras were used to monitor behavior of hens in each cage for a 24-h period at 19, 24, 29, 34, 39, 44, 49, 54, 59, 64, and 69 wk of age. Behavior was also recorded twice weekly by an observer in the room where the hens were housed during photophase from 25 to 68 wk of age. Behavioral data were analyzed using ANOVA with repeated measures and the MIXED model procedure. A greater proportion of hens without perches as pullets used the rear perch more during both photophase and scotophase than hens with prior pullet perching experience. Eating and drinking activities of caged adult Leghorns were not impaired by their prior experience to perches as pullets or by the presence of perches in laying cages. It is concluded that providing perches in cages to White Leghorns during pullet rearing did not facilitate use of perches as adults.

  8. Tactile Teaching: Exploring Protein Structure/Function Using Physical Models

    Science.gov (United States)

    Herman, Tim; Morris, Jennifer; Colton, Shannon; Batiza, Ann; Patrick, Michael; Franzen, Margaret; Goodsell, David S.

    2006-01-01

    The technology now exists to construct physical models of proteins based on atomic coordinates of solved structures. We review here our recent experiences in using physical models to teach concepts of protein structure and function at both the high school and the undergraduate levels. At the high school level, physical models are used in a…

  9. The hatching results of indigenous Hungarian speckled hens

    Directory of Open Access Journals (Sweden)

    Ákos Benk

    2016-05-01

    Full Text Available In the pilot farm of Szeged University Faculty of Agriculture we keep two varieties of the Hungarian speckled hen, the feathered-neck variant and the naked-neck type since 1977. The three colour variations of the domestic hen species were bred from the Hungarian lea-land bird by the middle of the 20th Century. Because of the spread of intensive poultry keeping the population of this species has become endangered. Programs supporting ecological-biological farming that began in the last two decades placed the domestically bred birds in the forefront both as purebreds and as candidates in projects for developing merchandisable bio-poultry. Beside the gene preservation, we endeavor to find the best way for the production-purpose utilisation of the speckled hen stock. On the basis of our experiments the laying hens can be used in small scale egg production. We examined the hatching results of both type of speckled hens, during more than 20 generations.

  10. A Novel Model for Protein Immobilization on Microspheres

    Institute of Scientific and Technical Information of China (English)

    WANG Di-qiang; LIU Bai-ling; LI He; HU Jie

    2004-01-01

    The immobilization of proteins, especially receptor proteins commonly used in high through-put screening of drugs (HTS), have received great attention in recent years. There are many successful isothermal models for describing the adsorption of protein onto solid surface, such as Langmuir model, Bi-Langmuir model, Fowler model, Freundlich model, Freundlich-Langmuir model and Tekmin model etc. In all these models, Langmuir model was the most favorable one model accepted by many researchers, but the experimental results showed that it was not entirely fit to all adsorption behaviors. So new models were required for describing protein adsorption onto microspheres in different conditions.In our research, a novel isothermal model, including Langmuir and other adsorbing behaviors was presented basing on the holding degree of surface active sites and the interaction styles of protein immobilization. In Langmuir model, the adsorbing amount of protein was described as [PS] =Km[P]/1 + K[P], where [PS] was the concentration of adsorbed protein, [P] was the concentration of freeprotein at equilibrium state, and Km and K was constant. According to the interactions of protein and ligands, there were three patterns in the interactions of protein and ligands. On the similar assumption that the interaction of protein and microspheres were three styles, and based on the definition of the holding degree of surface active sites (Y), three adsorption behaviors could be described as Y K[ P ]φ/ K[P]φ+1 or ln K + φ ln[P] =ln(Y/1-Y) in which [P] was the concentration of free protein at equilibrium state, and φ and K was constant. Different scale of φ presented different adsorption behaviors, especially when φ was 1, the adsorption behavior was Langmuir adsorbing model. Figure I indicated the different adsorbing results in different adsorption behaviors (φ>1, φ<1,and φ=1).

  11. Effects of dietary antioxidant on performance and physiological responses following heat stress in laying hens

    Science.gov (United States)

    Heat stress (HS) causes oxidative damage, increasing mortality and reducing productivity in chickens. The objective of this study was to determine the benefits of antioxidant supplementation in laying hens during HS. Eighty 32-wk-old W-36 White Leghorn hens were used in this study. Hens were randoml...

  12. Effects of organic selenium and zinc on the aging process of laying hens

    Science.gov (United States)

    The objective of the study was to determine whether supplementing the diets of post-molted hens with organic selenium (Se) (Sel-Plex®) and/or organic Zinc (Zn) (Bio-Plex®) could improve laying hen performance. Prior to molting, 120-78 wk old laying hens were separated into four treatment groups of ...

  13. Temporal and Sequential Structure of Behavior and Facility Usage of Laying Hens in an Enriched Environment

    NARCIS (Netherlands)

    Mishra, A.K.; Koene, P.; Schouten, W.G.P.; Spruijt, B.M.; Beek, van P.; Metz, J.H.M.

    2005-01-01

    Improved housing for laying hens may start from the translation of their behavioral needs into welfare-based design parameters for laying hen houses. The objective of our research was to gain insights into the facility usage and behavioral needs of the hen over 24 h when there are no obvious restrai

  14. Temporal and Sequential Structure of Behavior and Facility Usage of Laying Hens in an Enriched Environment

    NARCIS (Netherlands)

    Mishra, A.K.; Koene, P.; Schouten, W.G.P.; Spruijt, B.M.; Beek, van P.; Metz, J.H.M.

    2005-01-01

    Improved housing for laying hens may start from the translation of their behavioral needs into welfare-based design parameters for laying hen houses. The objective of our research was to gain insights into the facility usage and behavioral needs of the hen over 24 h when there are no obvious

  15. Protein comparative sequence analysis and computer modeling.

    Science.gov (United States)

    Hambly, Brett D; Oakley, Cecily E; Fajer, Piotr G

    2008-01-01

    A problem frequently encountered by the biological scientist is the identification of a previously unknown gene or protein sequence, where there are few or no clues as to the biochemical function, ligand specificity, gene regulation, protein-protein interactions, tissue specificity, cellular localization, developmental phase of activity, or biological role. Through the process of bioinformatics there are now many approaches for predicting answers to at least some of these questions, often then allowing the design of more insightful experiments to characterize more definitively the new protein.

  16. THE EFFECTS OF DIETS CONTAINING DIFFERENT LEVEL OF NON-STARCH POLYSACCHARIDES ON PERFORMANCE AND CANNIBALISM IN LAYING HENS

    Directory of Open Access Journals (Sweden)

    S. Hartini

    2014-10-01

    Full Text Available An experiment was conducted to observe the effect of different diets containing different level ofnon-starch polysaccharides (NSP on performance and cannibalism of laying hens. Six diets (wheatbased,rice hull-based, plant protein-based, millrun-based, MOS, and bentonite were used and wererandomly given to 6 groups of ISA Brown hens, with 18 replicates per group and 5 birds per replicatefor 8 weeks. The results showed that diets did not have a significant effect (P>0.05 on cannibalismmortality, but numerically the rice hull diet gave the lowest effect, the millrun gave the intermediateeffect, whereas the plant protein diet gave the largest negative effect. Diet significantly affected feedintake (P<0.01, egg production (P<0.01, feed to egg ratio (P<0.01 and egg weight (P<0.05. Birds onmillrun diet had the lowest intake, but the feed to egg ratio was superior and egg production was thehighest compared to those fed other diets. In contrast, the feed to egg ratio in rice hull diet was inferior,and egg weight was also lighter than those fed other diets. In conclusion, fibre sources have beenverified as contributing factors involved in the outbreak of cannibalism in laying hens. Diets containinghigh insoluble NSP had a potential to decrease the mortality due to cannibalism.

  17. Digestibility and physico-chemical characteristics of acid silage meal made of pirarucu waste in diets for commercial laying hens

    Directory of Open Access Journals (Sweden)

    Oscarina de Souza Batalha

    2017-07-01

    Full Text Available The objective of this study was to evaluate the effects of acid silage meal made of pirarucu waste in diets for commercial laying hens on apparent digestibility and energy metabolism. Seventy-two Hisex White hens with 71 weeks of age were assigned to a completely randomized with two treatments (control diet and diet with 3% pirarucu waste acid silage with six replicates of six birds each. The ensiled biomass was light brown in color, showing acidified aroma; creamy consistency; 4.38±0.11 pH; 84.16% dry matter; 40.06% crude protein; 26.82% ether extract; 9.31% mineral matter, 65.16 g kg-1 calcium and 22.90 g kg-1 phosphorus. Differences (p > 0.05 were detected in digestibility of crude protein, non-fiber carbohydrates (soluble carbohydrates, etherextract, mineral matter, metabolizable energy and metabolizable energy coefficient. Our results indicate that the acid silage mealmade of pirarucu waste can be included up to 3% in diets for laying hens, showing satisfactory nutrient digestibility and potential to be used as an energy source.

  18. Effects of organometallic chelates and inulin in diets for laying hens on Mn and Fe absorption coefficients and their content in egg and tissue

    Directory of Open Access Journals (Sweden)

    Cornescu Gabriela Maria

    2015-01-01

    Full Text Available The aim of this study was to evaluate effects of organic sources of manganese (Mn and iron (Fe and inulin in diets for laying hens on absorption of these minerals and their deposition in egg and tissue. The study was conducted on 90 Lohmann Brown laying hens in the period from 46-52 weeks of age, assigned to 3 groups with 30 hens/group and 3 hens/cage. The hens from the control group (C received a diet based on corn, rice bran and soybean meal with 16% of crude protein, as well as 60 mg Fe/kg and 71.9 mg Mn/kg of diet in form of inorganic salts. The formulation of the experimental diets (E1 and E2 differed from C group diet by the replacement of inorganic Fe and Mn salts by organometallic chelates of these elements, at a level of 25% lower than in the premix for group C. As source of inulin, group E1 diet also included 0.5% of dry Jerusalem artichoke, while group E2 diet included 0.5% of a product based on chicory root extract. At the end of the experiment, 6 hens from each group were slaughtered and blood serum and liver samples were collected and assayed for concentration of Fe and Mn. In the final week of the experiment, 18 eggs/group were collected for determination of Fe and Mn concentration in egg yolk. Concentration of measured blood serum parameters (haemoglobin, haematocrit, Fe and Mn in experimental (E groups were lower than in group C, but no significant differences (P>0.05 were registered. Absorption coefficients of Mn had higher values in E groups than in group C, with significant increase (P0.05 between groups were observed for Mn and Fe concentration in egg yolk.

  19. Mechanical Modeling and Computer Simulation of Protein Folding

    Science.gov (United States)

    Prigozhin, Maxim B.; Scott, Gregory E.; Denos, Sharlene

    2014-01-01

    In this activity, science education and modern technology are bridged to teach students at the high school and undergraduate levels about protein folding and to strengthen their model building skills. Students are guided from a textbook picture of a protein as a rigid crystal structure to a more realistic view: proteins are highly dynamic…

  20. Differentially Expressed Genes for Aggressive Pecking Behaviour in Laying Hens

    DEFF Research Database (Denmark)

    Buitenhuis, Bart; Hedegaard, Jakob; Janss, Luc

    2009-01-01

    Background Aggressive behaviour is an important aspect in the daily lives of animals living in groups. Aggressive animals have advantages, such as better access to food or territories, and they produce more offspring than low ranking animals. The social hierarchy in chickens is measured using the...... expressed genes may elucidate how the pecking order forms in laying hens at a molecular level....... the 'pecking order' concept, which counts the number of aggressive pecks given and received. To date, little is known about the underlying genetics of the 'pecking order'. Results A total of 60 hens from a high feather pecking selection line were divided into three groups: only receivers (R), only peckers (P...... binding (GO:0035254). Conclusion In conclusion, our study provides new insights into which genes are involved in aggressive behaviours in chickens. Pecking and receiving hens exhibited different gene expression profiles in their brains. Following confirmation, the identification of differentially...

  1. Litter use by laying hens in a commercial aviary: dust bathing and piling.

    Science.gov (United States)

    Campbell, D L M; Makagon, M M; Swanson, J C; Siegford, J M

    2016-01-01

    The laying hen industry, including in the United States, is responding to social concerns about hen welfare by implementing alternative housing systems such as the aviary, to provide more space and resources to large groups of hens. Data detailing the behavior of hens in commercial aviaries is needed to determine hens' use of the resources in order to understand their impact on hen welfare. The open litter area of aviaries provides additional space for hens during the day. Litter is also a substrate for dust bathing which is a strongly motivated natural behavior. Hens are often synchronous in their performance of dust bathing, which may lead to overcrowding in the litter area. Additionally, the open litter area can facilitate expression of unusual behavior such as flock piling (defined as the occurrence of densely grouped clusters of hens, resulting from no obvious cause and occurring randomly throughout the day and flock cycle) which may be a welfare concern. Therefore, we conducted observations of hen occupancy of the open litter area and the performance of dust bathing and flock piling across 3 production points (peak lay, mid lay and end of lay) for two flocks of Lohmann White laying hens housed in a commercial aviary. All areas of the open litter area were occupied to the same degree. Hens performed dust bathing throughout the day but showed peak dust bathing activity in the afternoon for Flock 1 (all P litter area sometimes occurred during peak periods of synchronous dust bathing and when hens piled. Further research is needed to understand the welfare implications of individual hen use of the open litter area and the causes and welfare implications of hen piling.

  2. Prediction of protein-protein interactions between viruses and human by an SVM model

    Directory of Open Access Journals (Sweden)

    Cui Guangyu

    2012-05-01

    Full Text Available Abstract Background Several computational methods have been developed to predict protein-protein interactions from amino acid sequences, but most of those methods are intended for the interactions within a species rather than for interactions across different species. Methods for predicting interactions between homogeneous proteins are not appropriate for finding those between heterogeneous proteins since they do not distinguish the interactions between proteins of the same species from those of different species. Results We developed a new method for representing a protein sequence of variable length in a frequency vector of fixed length, which encodes the relative frequency of three consecutive amino acids of a sequence. We built a support vector machine (SVM model to predict human proteins that interact with virus proteins. In two types of viruses, human papillomaviruses (HPV and hepatitis C virus (HCV, our SVM model achieved an average accuracy above 80%, which is higher than that of another SVM model with a different representation scheme. Using the SVM model and Gene Ontology (GO annotations of proteins, we predicted new interactions between virus proteins and human proteins. Conclusions Encoding the relative frequency of amino acid triplets of a protein sequence is a simple yet powerful representation method for predicting protein-protein interactions across different species. The representation method has several advantages: (1 it enables a prediction model to achieve a better performance than other representations, (2 it generates feature vectors of fixed length regardless of the sequence length, and (3 the same representation is applicable to different types of proteins.

  3. Microbiological impact of three commercial laying hen housing systems.

    Science.gov (United States)

    Jones, D R; Cox, N A; Guard, J; Fedorka-Cray, P J; Buhr, R J; Gast, R K; Abdo, Z; Rigsby, L L; Plumblee, J R; Karcher, D M; Robison, C I; Blatchford, R A; Makagon, M M

    2015-03-01

    Hen housing for commercial egg production continues to be a societal and regulatory concern. Controlled studies have examined various aspects of egg safety, but a comprehensive assessment of commercial hen housing systems in the US has not been conducted. The current study is part of a holistic, multidisciplinary comparison of the diverse aspects of commercial conventional cage, enriched colony cage, and cage-free aviary housing systems and focuses on environmental and egg microbiology. Environmental swabs and eggshell pools were collected from all housing systems during 4 production periods. Total aerobes and coliforms were enumerated, and the prevalence of Salmonella and Campylobacter spp. was determined. Environmental aerobic and coliform counts were highest for aviary drag swabs (7.5 and 4.0 log cfu/mL, respectively) and enriched colony cage scratch pad swabs (6.8 and 3.8 log cfu/mL, respectively). Aviary floor and system wire shell pools had the greatest levels of aerobic contamination for all eggshell pools (4.9 and 4.1 log cfu/mL, respectively). Hens from all housing systems were shedding Salmonella spp. (89-100% of manure belt scraper blade swabs). The dry belt litter removal processes for all housing systems appear to affect Campylobacter spp. detection (0-41% of manure belt scraper blade swabs) considering detection of Campylobacter spp. was much higher for other environmental samples. Aviary forage area drag swabs were 100% contaminated with Campylobacter spp., whereas enriched colony cage scratch pads had a 93% positive rate. There were no differences in pathogen detection in the shell pools from the 3 housing systems. Results indicate egg safety is enhanced when hens in alternative housing systems use nest boxes. Additionally, current outcomes indicate the use of scratch pads in hen housing systems needs to be more thoroughly investigated for effects on hen health and egg safety.

  4. Hydrodynamic multibead modeling: problems, pitfalls, and solutions. 2. Proteins.

    Science.gov (United States)

    Zipper, Peter; Durchschlag, Helmut

    2010-02-01

    Hydrodynamic models of proteins have been generated by recourse to crystallographic data and applying a filling model strategy in order to predict both hydrodynamic and scattering parameters. The design of accurate protein models retaining the majority of the molecule peculiarities requires usage of many beads and consideration of many serious problems. Applying the expertise obtained with ellipsoid models and pilot tests on proteins, we succeeded in constructing precise models for several anhydrous and hydrated proteins of different shape, size, and complexity. The models constructed consist of many beads (up to about 11,000) for the protein constituents (atoms, amino acid residues, groups) and preferentially bound water molecules. While in the case of small proteins, parameter predictions are straightforward, computations for giant proteins necessitate drastic reductions of the number of initially available beads. Among several auxiliary programs, our advanced hydration programs, HYDCRYST and HYDMODEL, and modified versions of García de la Torre's program HYDRO were successfully employed. This allowed the generation of realistic protein models by imaging details of their fine structure and enabled the prediction of reliable molecular parameters including intrinsic viscosities. The appearance of the models and the agreement of molecular properties and distance distribution functions p(r) of unreduced and reduced models can be used for a meticulous inspection of the data obtained.

  5. Response of laying hens to methionine + cystine intake by dilution technique

    Directory of Open Access Journals (Sweden)

    Hilda Cristina Palma Bendezu

    2015-01-01

    Full Text Available The objective of this study was to measure the response of Dekalb White laying hens to different intakes of digestible methionine + cystine (met+cys to optimise their performance. Two hundred eighty-eight Dekalb White laying hens, ranging in age from 33 to 48 weeks, were used in the study. The birds were randomly allocated into eight treatment (levels of met+cys and the control treatment groups with six replicates of six hens per unit. The experimental diets consisted of seven increasing levels of met+cys (1.37, 2.75, 4.14, 5.51, 6.89, 7.92 and 8.95 g kg−1 and were prepared using a dilution technique. A control treatment was used to confirm that the limiting response was due to met+cys intake. Egg production, feed intake, egg weight, egg mass and feed conversion per mass were measured. The data were analysed with repeated measures and regression analyses using Broken Line and Quadratic models, as well as using the combination of both models. The different met+cys intakes influenced the studied variables; all the variables except feed conversion per mass were significantly different between the periods and levels. The digestible met+cys intakes based on the association of the Broken Line and Quadratic models to optimise the birds' response to egg mass are 671 mg/bird d for 33 to 36 weeks, 728 mg/bird d for 37 to 40 weeks, 743 mg/bird d for 41 to 44 weeks, and 770 mg/bird d for 45 to 48 weeks.

  6. Pharmacokinetics of doxycycline in laying hens after intravenous and oral administration.

    Science.gov (United States)

    Yang, F; Si, H B; Wang, Y Q; Zhao, Z S; Zhou, B H; Hao, X Q

    2016-08-01

    The pharmacokinetics of doxycycline in laying hens was investigated after a single intravenous (IV) or an oral (PO) dose at 20 mg/kg body weight. The concentrations of doxycycline in plasma samples were determined by high-performance liquid chromatography with an ultraviolet detector, and pharmacokinetic parameters were calculated using a compartmental model method. The disposition of doxycycline after one single IV injection was best described by a two-compartment open model and the main pharmacokinetic parameters were as follows: volume of distribution (Vd) was 865.15 ± 127.64 ml/kg, distribution rate constant (α) was (2.28 ± 0.38) 1/h, elimination rate constant (β) was 0.08 ± 0.02 1/h and total body clearance (Cl) was104.11 ± 18.32 ml/h/kg, while after PO administration, the concentration versus time curve was best described by a one-compartment open model and absorption rate constant (Ka), peak concentration (Cmax), time to reach Cmax (tmax) and absolute bioavailability (F) were 2.55 ± 1.40 1/h, 5.88 ± 0.70 μg/ml, 1.73 ± 0.75 h and 52.33%, respectively. The profile of doxycycline exhibited favourable pharmacokinetic characteristics in laying hens, such as quick absorption and slow distribution and elimination, though oral bioavailability was relatively low. A multiple-dosing regimen (a dose of 20 mg/kg/d for 3 consecutive days) of doxycycline was recommended to treat infections in laying hens. But a further study should be conducted to determine the withdrawal time of doxycycline in eggs.

  7. Protein adsorption on nanoparticles: model development using computer simulation

    Science.gov (United States)

    Shao, Qing; Hall, Carol K.

    2016-10-01

    The adsorption of proteins on nanoparticles results in the formation of the protein corona, the composition of which determines how nanoparticles influence their biological surroundings. We seek to better understand corona formation by developing models that describe protein adsorption on nanoparticles using computer simulation results as data. Using a coarse-grained protein model, discontinuous molecular dynamics simulations are conducted to investigate the adsorption of two small proteins (Trp-cage and WW domain) on a model nanoparticle of diameter 10.0 nm at protein concentrations ranging from 0.5 to 5 mM. The resulting adsorption isotherms are well described by the Langmuir, Freundlich, Temkin and Kiselev models, but not by the Elovich, Fowler-Guggenheim and Hill-de Boer models. We also try to develop a generalized model that can describe protein adsorption equilibrium on nanoparticles of different diameters in terms of dimensionless size parameters. The simulation results for three proteins (Trp-cage, WW domain, and GB3) on four nanoparticles (diameter  =  5.0, 10.0, 15.0, and 20.0 nm) illustrate both the promise and the challenge associated with developing generalized models of protein adsorption on nanoparticles.

  8. RNA and protein 3D structure modeling: similarities and differences.

    Science.gov (United States)

    Rother, Kristian; Rother, Magdalena; Boniecki, Michał; Puton, Tomasz; Bujnicki, Janusz M

    2011-09-01

    In analogy to proteins, the function of RNA depends on its structure and dynamics, which are encoded in the linear sequence. While there are numerous methods for computational prediction of protein 3D structure from sequence, there have been very few such methods for RNA. This review discusses template-based and template-free approaches for macromolecular structure prediction, with special emphasis on comparison between the already tried-and-tested methods for protein structure modeling and the very recently developed "protein-like" modeling methods for RNA. We highlight analogies between many successful methods for modeling of these two types of biological macromolecules and argue that RNA 3D structure can be modeled using "protein-like" methodology. We also highlight the areas where the differences between RNA and proteins require the development of RNA-specific solutions.

  9. Effect of coronavirus infection on reproductive performance of turkey hens.

    Science.gov (United States)

    Awe, Olusegun O; Ali, Ahmed; Elaish, Mohamed; Ibrahim, Mahmoud; Murgia, Maria; Pantin-Jackwood, Mary; Saif, Yehia M; Lee, Chang-Won

    2013-09-01

    Turkey coronavirus (TCoV) infection causes enteritis in turkeys of varying ages with high mortality in young birds. In older birds, field evidence indicates the possible involvement of TCoV in egg-production drops in turkey hens. However, no experimental studies have been conducted to demonstrate TCoV pathogenesis in turkey hens and its effect on reproductive performance. In the present study, we assessed the possible effect of TCoV on the reproductive performance of experimentally infected turkey hens. In two separate trials, 29- to 30-wk-old turkey hens in peak egg production were either mock-infected or inoculated orally with TCoV (Indiana strain). Cloacal swabs and intestinal and reproductive tissues were collected and standard reverse-transcription PCR was conducted to detect TCoV RNA. In the cloacal swabs, TCoV was detected consistently at 3, 5, 7, and 12 days postinoculation (DPI) with higher rates of detection after 5 DPI (> 90%). All intestinal samples were also positive for TCoV at 7 DPI, and microscopic lesions consisting of severe enteritis with villous atrophy were observed in the duodenum and jejunum of TCoV-infected hens. In one of the trials TCoV was detected from the oviduct of two birds at 7 DPI; however, no or mild microscopic lesions were present. In both experimental trials an average of 28%-29% drop in egg production was observed in TCoV-infected turkey hens between 4 and 7 DPI. In a separate trial we also confirmed that TCoV can efficiently transmit from infected to contact control hens. Our results show that TCoV infection can affect the reproductive performance in turkey hens, causing a transient drop in egg production. This drop in egg production most likely occurred as consequence of the severe enteritis produced by the TCoV. However, the potential replication of TCoV in the oviduct and its effect on pathogenesis should be considered and further investigated.

  10. A revised artificial insemination schedule for broiler breeder hens.

    Science.gov (United States)

    Van Krey, H P; Siegel, P B

    1976-03-01

    Broiler type hens maintained in individual cages were artificially inseminated with either 0.023, 0.035, or 0.047 ml. of pooled semen. Insemination intervals were nine, nine, and ten days on a repetitive basis. This schedule was adopted because it allowed an extension of the conventional insemination interval and yet remained compatible with a five-day industrial work-week. The results demonstrated that maintaining broiler breeder hens in cages and utilizing artificial insemination as a means of obtaining fertile eggs were feasible. The data also indicated that extending the insemination interval to 10 days is possible providing the number of spermatozoa inseminated is increased.

  11. Tracking membrane protein association in model membranes.

    Directory of Open Access Journals (Sweden)

    Myriam Reffay

    Full Text Available Membrane proteins are essential in the exchange processes of cells. In spite of great breakthrough in soluble proteins studies, membrane proteins structures, functions and interactions are still a challenge because of the difficulties related to their hydrophobic properties. Most of the experiments are performed with detergent-solubilized membrane proteins. However widely used micellar systems are far from the biological two-dimensions membrane. The development of new biomimetic membrane systems is fundamental to tackle this issue.We present an original approach that combines the Fluorescence Recovery After fringe Pattern Photobleaching technique and the use of a versatile sponge phase that makes it possible to extract crucial informations about interactions between membrane proteins embedded in the bilayers of a sponge phase. The clear advantage lies in the ability to adjust at will the spacing between two adjacent bilayers. When the membranes are far apart, the only possible interactions occur laterally between proteins embedded within the same bilayer, whereas when membranes get closer to each other, interactions between proteins embedded in facing membranes may occur as well.After validating our approach on the streptavidin-biotinylated peptide complex, we study the interactions between two membrane proteins, MexA and OprM, from a Pseudomonas aeruginosa efflux pump. The mode of interaction, the size of the protein complex and its potential stoichiometry are determined. In particular, we demonstrate that: MexA is effectively embedded in the bilayer; MexA and OprM do not interact laterally but can form a complex if they are embedded in opposite bilayers; the population of bound proteins is at its maximum for bilayers separated by a distance of about 200 A, which is the periplasmic thickness of Pseudomonas aeruginosa. We also show that the MexA-OprM association is enhanced when the position and orientation of the protein is restricted by the

  12. From Genomes to Protein Models and Back

    Science.gov (United States)

    Tramontano, Anna; Giorgetti, Alejandro; Orsini, Massimiliano; Raimondo, Domenico

    2007-12-01

    The alternative splicing mechanism allows genes to generate more than one product. When the splicing events occur within protein coding regions they can modify the biological function of the protein. Alternative splicing has been suggested as one way for explaining the discrepancy between the number of human genes and functional complexity. We analysed the putative structure of the alternatively spliced gene products annotated in the ENCODE pilot project and discovered that many of the potential alternative gene products will be unlikely to produce stable functional proteins.

  13. Occurrence of Salmonella sp in laying hens

    Directory of Open Access Journals (Sweden)

    Gama NMSQ

    2003-01-01

    Full Text Available This study was carried out to investigate the presence of Salmonella sp in flocks of white laying hens. In different farms, the transport boxes of twelve flocks were inspected at arrival for the presence of Salmonella. Four positive (A, B, L and M and one negative (I flocks were monitored at each four weeks using bacteriological examination of cecal fresh feces up to 52 weeks. Birds were also evaluated at 52 weeks, when 500 eggs were taken randomly, and at 76 weeks, after forced molt. Salmonella enterica serovar Enteritidis and S. enterica rough strain were isolated from the transport boxes of the four positive flocks (flocks A, B, L and M. Salmonella sp was not isolated from the transport boxes or from the feces after 76 weeks-old in flock I. Salmonella sp was isolated in the 1st, 11th, 34th, 42nd and 76th weeks from flock A; in the 1st, 4th, 11th and 76th weeks from flock B; in the first week and in the 17th to 52nd weeks from flock L; and in the 1st and 76th weeks from flock M. S. Enteritidis, S. enterica rough strain and Salmonella enterica serovar Infantis were isolated from the four positive flocks. Besides, Salmonella enterica serovar Javiana was isolated from flocks B and L, and Salmonella enterica serovar Mbandaka was isolated from flock L. Eggs produced by flock A and by flock L were contaminated with S. Enteritidis and S. enterica rough strain. According to these results, Salmonella-infected flocks may produce contaminated eggs.

  14. Effect of corticosterone and hen body mass on primary sex ratio in laying hen (Gallus gallus), using unincubated eggs.

    Science.gov (United States)

    Aslam, Muhammad Aamir; Groothuis, Ton G G; Smits, Mari A; Woelders, Henri

    2014-04-01

    In various studies, chronic elevation of corticosterone levels in female birds under natural or experimental conditions resulted in female biased offspring sex ratios. In chicken, one study with injected corticosterone resulted in a male sex ratio bias. In the current study, we chronically elevated blood plasma corticosterone levels through corticosterone feeding (20 mg/kg feed) for 14 days using 30 chicken hens in each of treatment and control groups and studied the primary offspring sex ratio (here defined as the proportion of male fertile eggs determined in freshly laid eggs, i.e., without egg incubation). Mean plasma corticosterone concentrations were significantly higher in the treatment group but were not associated with sex ratio, laying rate, and fertility rate. Corticosterone treatment by itself did not affect egg sex but affected sex ratio as well as laying rate and fertility rate in interaction with hen body mass. Body mass had a negative association with sex ratio, laying rate, and fertility rate per hen in the corticosterone group, but a positive association with sex ratio in untreated hens. These interactions were already seen when taking the body mass at the beginning of the experiment, indicating intrinsic differences between light and heavy hens with regard to their reaction to corticosterone treatment. The effects on laying rate, fertility rate, and sex ratio suggest that some factor related to body mass act together with corticosterone to modulate ovarian functions. We propose that corticosterone treatment in conjunction with hen body mass can interfere with meiosis, which can lead to meiotic drive and to chromosomal aberrations resulting in postponed ovulation or infertile ova.

  15. Chaos game representation walk model for the protein sequences

    Institute of Scientific and Technical Information of China (English)

    Gao Jie; Jiang Li-Li; Xu Zhen-Yuan

    2009-01-01

    A new chaos game representation of protein sequences based on the detailed hydrophobic-hydrophilic(HP)model has been proposed by Yu et al(Physica A 337(2004)171). A CGR-walk model is proposed based on the new CGR coordinates for the protein sequences from complete genomes in the present paper. The new CGR coordinates based on the detailed HP model are converted into a time series, and a long-memory ARFIMA(p, d, q)model is introduced into the protein sequence analysis. This model is applied to simulating real CGR-walk sequence data of twelve protein sequences. Remarkably long-range correlations are uncovered in the data and the results obtained from these models are reasonably coneistent with those available from the ARFIMA(p, d, q)model.

  16. A binary logistic regression model for discriminating real protein-protein interface

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The selection and study of descriptive variables of protein-protein complex interface is a major question that many biologists come across when the research of protein-protein recognition is concerned. Several variables have been proposed to understand the structural or energetic features of complex interfaces. Here a systematic study of some of these "traditional" variables, as well as a few new ones, is introduced. With the values of these variables extracted from 42 PDB samples with real or false complex interfaces, a binary logistic regression analysis is performed, which results in an effective empirical model for the evaluation of binding probabilities of protein-protein interfaces. The model is validated with 12 samples, and satisfactory results are obtained for both the training and validation sets. Meanwhile, three potential dimeric interfaces of staphylokinase have been investigated and one with the best suitability to our model is proposed.

  17. Predicting nucleic acid binding interfaces from structural models of proteins.

    Science.gov (United States)

    Dror, Iris; Shazman, Shula; Mukherjee, Srayanta; Zhang, Yang; Glaser, Fabian; Mandel-Gutfreund, Yael

    2012-02-01

    The function of DNA- and RNA-binding proteins can be inferred from the characterization and accurate prediction of their binding interfaces. However, the main pitfall of various structure-based methods for predicting nucleic acid binding function is that they are all limited to a relatively small number of proteins for which high-resolution three-dimensional structures are available. In this study, we developed a pipeline for extracting functional electrostatic patches from surfaces of protein structural models, obtained using the I-TASSER protein structure predictor. The largest positive patches are extracted from the protein surface using the patchfinder algorithm. We show that functional electrostatic patches extracted from an ensemble of structural models highly overlap the patches extracted from high-resolution structures. Furthermore, by testing our pipeline on a set of 55 known nucleic acid binding proteins for which I-TASSER produces high-quality models, we show that the method accurately identifies the nucleic acids binding interface on structural models of proteins. Employing a combined patch approach we show that patches extracted from an ensemble of models better predicts the real nucleic acid binding interfaces compared with patches extracted from independent models. Overall, these results suggest that combining information from a collection of low-resolution structural models could be a valuable approach for functional annotation. We suggest that our method will be further applicable for predicting other functional surfaces of proteins with unknown structure. Copyright © 2011 Wiley Periodicals, Inc.

  18. Persönliche Ziele im frühen Erwachsenenalter. Eine längsschnittliche Analyse

    OpenAIRE

    Heismann, Christiane

    2012-01-01

    Welche persönlichen Zielinhalte verfolgen junge Menschen im Verlauf des frühen Erwachsenenalters? Gibt es dabei systematische Veränderungen? Welche Kontextfaktoren beeinflussen persönliche Ziele? Diesen Fragen ist die vorliegende Arbeit nachgegangen. Auf der Grundlage handlungstheoretischer Ansätze und lebensspannenbezogener Entwicklungstheorien wurde ein integratives Modell der Einflussfaktoren persönlicher Ziele gebildet. Ziele werden als Ergebnis des Zusammenwirkens altersnormativer Anford...

  19. Laying hen movement in a commercial aviary: Enclosure to floor and back again.

    Science.gov (United States)

    Campbell, D L M; Makagon, M M; Swanson, J C; Siegford, J M

    2016-01-01

    Many producers in the laying hen industry, including in North America, are phasing out conventional cages in response to consumer demands and sometimes subsequent legislation. Alternative housing systems such as aviaries are being implemented in an attempt to improve hen welfare. Aviaries provide additional space and resources to groups of hens, including a litter area on the floor. However, little is known about hen movement between tiered enclosures and floor litter areas in aviary systems. Diurnal rhythms and social attraction may result in peak times of movement that could lead to overcrowding of areas, or alternatively hen preferences may lead to some areas not being fully utilized. We monitored hen movement between tiered enclosures and litter areas, including movement on and off the outer perch, across the day at peak, mid and end of lay in a commercial aviary. Hens moved onto and off of the open litter area across the day, transitioning between tiered enclosures, outer perches, open litter areas, and litter areas under tiered enclosures. At certain times of day, there were periods of greater hen movement down to the open litter area and between litter areas. For example, more hens were typically observed exiting enclosures, jumping from perches to open litter, and traveling between open litter and litter under tiered enclosures in the morning (all P ≤ 0.001). In all but one instance, more hens were observed on open litter areas in the afternoon than at other times of day (all P ≤ 0.029). However, hen re-entry to tiered enclosures showed less circadian patterning. Hen movement was observed between areas of interest at all sampled time periods, indicating hens use all areas of the system. Further research should examine whether all individual hens do move between areas equally, including within levels of the tiered enclosure, or if crowding occurs on the outer perches or in the litter during times of peak movement.

  20. Physiological responses of hens divergently selected on the number of chicks obtained from a single insemination.

    Science.gov (United States)

    Brillard, J P; Beaumont, C; Scheller, M F

    1998-09-01

    A series of experiments was conducted in domestic fowl to investigate the consequences of five generations of divergent selection for increased (L+) or decreased (L-) numbers of hatched chicks. After artificial insemination with pooled ejaculates within the same line (L+ males x L+ hens or L- males x L- hens), significant differences were observed between L+ and L- hens for mean fertility rates (L+ 94.8%, L- 70.2%, P hens laid fewer eggs than L+ hens (P hens compared with L+ hens. Another series of experiments revealed the presence of larger initial populations of spermatozoa in the sperm storage tubules as well as in the perivitelline layer of eggs from L+ hens. The populations of spermatozoa in the sperm storage tubules of commercial laying hens inseminated with pooled semen samples from L+ males was compared with those in hens inseminated with samples from L- males to determine whether the variations in oviductal sperm storage between the two lines were male dependent. No significant differences between the populations of spermatozoa present in the sperm storage tubules of either group of hens could be detected at any of the intervals examined after insemination (days 1, 3 and 10). Finally, an experiment conducted on hens originating from the two selected lines indicated that the utero-vaginal junction of L+ hens contained significantly more sperm storage tubules compared with L- hens (P < 0.01). It is concluded that selection based on overall reproductive performance modifies the number of eggs capable of developing viable embryos and also influences the efficacy of initial sperm storage by increasing or altering the population of sperm storage tubules located in the utero-vaginal junction. Such changes have major consequences on the duration of the fertile period, which in avian species is directly dependent on both the actual population of spermatozoa stored in the oviduct and on their rate of release from the storage sites.

  1. Performance and welfare of laying hens in conventional and enriched cages.

    Science.gov (United States)

    Tactacan, G B; Guenter, W; Lewis, N J; Rodriguez-Lecompte, J C; House, J D

    2009-04-01

    Concerns regarding the welfare of laying hens raised in battery cages have led to the development of enriched cages that allow hens to perform natural behaviors including nesting, roosting, and scratching. This study was conducted to compare indices of production and welfare in birds housed in 2 different caging systems. Shaver White hens were housed from 21 to 61 wk in either conventional battery cages (n = 500; 10 cages; 5 hens/cage; floor space = 561.9 cm(2)/hen) or enriched cages (n = 480; 2 cages; 24 hens/cage; floor space = 642.6 cm(2)/hen) and were replicated 10 times. Enriched cages provided hens with a curtained nesting area, scratch pad, and perches. Production parameters and egg quality measures were recorded throughout the experiment. Plumage condition was evaluated at 37 and 61 wk. Bone quality traits and immunological response parameters were measured at 61 wk, and 59 and 61 wk, respectively. Hen-day egg production, feed consumption, egg weight, and percentage of cumulative mortality of laying hens were not affected by the cage designs. Specific gravity and the percentage of cracked and soft-shelled eggs were also similar between the 2 housing systems. The incidence of dirty eggs was, however, significantly higher (P cages than in conventional cages. Feather scores were similar between birds except for the wing region, which was higher (P cages. Bone quality measures tended to be higher for hens housed in enriched cages compared with hens in conventional cages. However, the increase was significant only for bone mineral density. Immunological response parameters did not reveal statistically significant differences. Overall, laying performance, exterior egg quality measures, plumage condition, and immunological response parameters appear to be similar for hens housed in the 2 cage systems tested. Enrichment of laying hen cages resulted in better bone quality, which could have resulted from increased activity.

  2. Enhancement of nucleation during hanging drop protein crystallization using HF treatment of cover glasses

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Yun-Zhu; Yin, Da-Chuan; Lu, Qin-Qin; Wang, Xi-Kai; Liu, Jun [Key Laboratory for Space Bioscience and Biotechnology, Faculty of Life Sciences, Northwestern Polytechnical University, Xi' an 710072, Shaanxi (China)

    2010-02-15

    We examined a simple approach, i.e., etching cover glasses using hydrofluoric acid (HF), to determine whether cover glass treatment enhances nucleation in hanging drop protein crystallization. Hen egg white lysozyme and proteinase K were used as the model proteins. We found that the treatment increased the success rate of crystallization. The results indicated that the simple treatment, which is easy to adopt without changing much in the hanging drop method, can be utilized as an alternative method to enhance protein crystallization screens (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. Lessons from making the Structural Classification of Proteins (SCOP) and their implications for protein structure modelling.

    Science.gov (United States)

    Andreeva, Antonina

    2016-06-15

    The Structural Classification of Proteins (SCOP) database has facilitated the development of many tools and algorithms and it has been successfully used in protein structure prediction and large-scale genome annotations. During the development of SCOP, numerous exceptions were found to topological rules, along with complex evolutionary scenarios and peculiarities in proteins including the ability to fold into alternative structures. This article reviews cases of structural variations observed for individual proteins and among groups of homologues, knowledge of which is essential for protein structure modelling.

  4. Parmodel: a web server for automated comparative modeling of proteins.

    Science.gov (United States)

    Uchôa, Hugo Brandão; Jorge, Guilherme Eberhart; Freitas Da Silveira, Nelson José; Camera, João Carlos; Canduri, Fernanda; De Azevedo, Walter Filgueira

    2004-12-24

    Parmodel is a web server for automated comparative modeling and evaluation of protein structures. The aim of this tool is to help inexperienced users to perform modeling, assessment, visualization, and optimization of protein models as well as crystallographers to evaluate structures solved experimentally. It is subdivided in four modules: Parmodel Modeling, Parmodel Assessment, Parmodel Visualization, and Parmodel Optimization. The main module is the Parmodel Modeling that allows the building of several models for a same protein in a reduced time, through the distribution of modeling processes on a Beowulf cluster. Parmodel automates and integrates the main softwares used in comparative modeling as MODELLER, Whatcheck, Procheck, Raster3D, Molscript, and Gromacs. This web server is freely accessible at .

  5. Protein and gene model inference based on statistical modeling in k-partite graphs.

    Science.gov (United States)

    Gerster, Sarah; Qeli, Ermir; Ahrens, Christian H; Bühlmann, Peter

    2010-07-06

    One of the major goals of proteomics is the comprehensive and accurate description of a proteome. Shotgun proteomics, the method of choice for the analysis of complex protein mixtures, requires that experimentally observed peptides are mapped back to the proteins they were derived from. This process is also known as protein inference. We present Markovian Inference of Proteins and Gene Models (MIPGEM), a statistical model based on clearly stated assumptions to address the problem of protein and gene model inference for shotgun proteomics data. In particular, we are dealing with dependencies among peptides and proteins using a Markovian assumption on k-partite graphs. We are also addressing the problems of shared peptides and ambiguous proteins by scoring the encoding gene models. Empirical results on two control datasets with synthetic mixtures of proteins and on complex protein samples of Saccharomyces cerevisiae, Drosophila melanogaster, and Arabidopsis thaliana suggest that the results with MIPGEM are competitive with existing tools for protein inference.

  6. Effects of Various Levels of Oxidized Oil on Performance, Egg Quality and Some Blood Metabolites in Laying Hens

    Directory of Open Access Journals (Sweden)

    AA Saki

    2016-06-01

    Full Text Available The influence of dietary oxidized oil was studied on laying hen performance, egg quality and blood metabolites.  Experiment was conducted on 160 laying hens (Hy-Line W-36, 54-61 wk of age in a completely randomized design with five treatments and four replicated cages containing eight birds per cage. Dietary treatments replaced fresh soybean oil in the control diet (3% fresh soybean oil, 15.25% crude protein, and 2858 Kcal/kg metabolizable energy with 0, 25, 50, 75 and 100% oxidized oil. Egg production and egg weight were recorded daily and feed intake, feed conversion ratio, and egg mass were calculated weekly. Egg quality traits were recorded on a biweekly basis. Hen’s body weight was measured individually at the beginning and end of the experiment. Serum metabolites were determined at the end of the experiment. There was a significant difference between diets with different oxidized oil levels in egg weight, egg mass, Egg production, and feed conversion ratio (P < 0.05. Feed intake was not affected by dietary treatments. There was no significant difference between oxidized oil levels on blood serum triglyceride, total cholesterol, high-density lipoprotein, low-density lipoprotein and very low-density lipoprotein. Malondialdehyde of the liver was not affected by oxidized oils. The results of this study have clearly demonstrated that maximum 25% oxidized oil could be replaced by fresh oil in the diets without any adverse effect on the performance of laying hens.

  7. Formation and seeding of amyloid fibrils from wild-type hen lysozyme and a peptide fragment from the beta-domain.

    Science.gov (United States)

    Krebs, M R; Wilkins, D K; Chung, E W; Pitkeathly, M C; Chamberlain, A K; Zurdo, J; Robinson, C V; Dobson, C M

    2000-07-14

    Wild-type hen lysozyme has been converted from its soluble native state into highly organized amyloid fibrils. In order to achieve this conversion, conditions were chosen to promote partial unfolding of the native globular fold and included heating of low-pH solutions and addition of organic solvents. Two peptides derived from the beta-sheet region of hen lysozyme were also found to form fibrils very readily. The properties and morphologies of the amyloid fibrils formed by incubation either of the protein or the peptides are similar to those produced from the group of proteins associated with clinical amyloidoses. Fibril formation by hen lysozyme was substantially accelerated when aliquots of solutions in which fibrils of either one of the peptides or the full-length protein had previously formed were added to fresh solutions of the protein, revealing the importance of seeding in the kinetics of fibril formation. These findings support the proposition that the beta-domain is of particular significance in the formation of fibrils from the full-length protein and suggest similarities between the species giving rise to fibril formation and the intermediates formed during protein folding. Copyright 2000 Academic Press.

  8. Differences in Physicochemical and Nutritional Properties of Breast and Thigh Meat from Crossbred Chickens, Commercial Broilers, and Spent Hens.

    Science.gov (United States)

    Chen, Yulian; Qiao, Yan; Xiao, Yu; Chen, Haochun; Zhao, Liang; Huang, Ming; Zhou, Guanghong

    2016-06-01

    The objective of this study was to compare the physicochemical and nutritional properties of breast and thigh meat from commercial Chinese crossbred chickens (817 Crossbred chicken, 817C), imported commercial broilers (Arbor Acres broiler, AAB), and commercial spent hens (Hyline Brown, HLB). The crossbred chickens, commercial broilers and spent hens were slaughtered at their typical market ages of 45 d, 40 d, and 560 d, respectively. The results revealed that several different characteristic features for the three breeds. The meat of the 817C was darker than that of the other two genotypes. The 817C were also characterized by higher protein, lower intramuscular fat, and better texture attributes (cooking loss, pressing loss and Warner-Bratzler shear force [WBSF]) compared with AAB and HLB. The meat of the spent hens (i.e. HLB) was higher in WBSF and total collagen content than meat of the crossbred chickens and imported broilers. Furthermore, correlation analysis and principal component analysis revealed that there was a clear relationship among physicochemical properties of chicken meats. With regard to nutritional properties, it was found that 817C and HLB exhibited higher contents of essential amino acids and essential/non-essential amino acid ratios. In addition, 817C were noted to have highest content of microelements whereas AAB have highest content of potassium. Besides, 817C birds had particularly higher proportions of desirable fatty acids, essential fatty acids, polyunsaturated/saturated and (18:0+18:1)/16:0 ratios. The present study also revealed that there were significant differences on breast meat and thigh meat for the physicochemical and nutritional properties, regardless of chicken breeds. In conclusion, meat of crossbred chickens has some unique features and exhibited more advantages over commercial broilers and spent hens. Therefore, the current investigation would provide valuable information for the chicken meat product processing, and

  9. Comparison of different extraction solutions for the analysis of allergens in hen's egg.

    Science.gov (United States)

    Hildebrandt, S; Steinhart, H; Paschke, A

    2008-06-01

    An important requirement for the correct procedure of allergen analysis in hen's egg is to obtain complete and unaltered protein extracts. Besides the aim of a quantitative extraction of the allergens from the matrix, it is equally important not to alter their allergenic potential during the extraction process. This paper describes and compares six extraction solutions for the analysis of whole-egg proteins and allergens. These requirements were examined via protein determination according to Bradford [Bradford, M. M. (1976). Rapid and sensitive method for quantitation of microgram quantities of protein utilizing principle of protein-dye binding. Analytical Biochemistry, 72, 248-254] and Kjeldahl [Meyer, A. H. (2006). Lebensmittelrecht, Verlag C.H. Beck München, Stand: 1. February 2006, § 64, Lebensmittel- und Futtermittelgesetzbuch, Amtliche Sammlung von Untersuchungsmethoden, Nr. L 06.00-7] as well as the EAST-inhibition method. It could be demonstrated that the extraction with a urea solution (8M) led to significant interferences during the protein determination, and substantially reduced the allergenic potential of egg proteins. With all other extraction solutions adequate protein contents could be extracted. The highest protein content was achieved by the extraction with phosphate buffered saline followed by a Tween 20 solution, physiological saline, water, and acetate buffer. The results show that none of these extracts - except for the urea solution (8M) - was altered in its' allergenic potential.

  10. Pathological Responses of White Leghorn Breeder Hens Kept on Ochratoxin A Contaminated Feed

    Directory of Open Access Journals (Sweden)

    Zahoor-ul-Hassan, M. Zargham Khan*, Ahrar Khan and Ijaz Javed1

    2010-04-01

    Full Text Available Mycotoxins are among the most important environmental contaminants. In the present study, ochratoxin A (OTA was produced by propagation of Aspergillus ochraceus and fed to breeder hens. For this purpose, 84 breeder hens were divided into seven groups (A-G. Group A served as control, while groups B, C, D, E, F and G were fed OTA at 0.1, 0.5, 1.0, 3.0, 5.0 and 10.0 mg/Kg feed, respectively for 3 weeks. Clinical signs, feed intake, feed conversion ratio and egg mass production were recorded on daily basis, while body weight was recorded on weekly basis. Lesions on visceral organs and serum biochemical parameters were determined. Significant decrease in feed intake, body weight and egg mass production was found in the OTA treated groups compared to control (P<0.05. Among different groups, diarrhea, unthriftiness, water intake and depression increased with increase in dietary OTA levels. Enlargement and hemorrhages on liver and kidney were more severe in birds fed higher dietary OTA levels. Serum ALT, urea, creatinine and total protein levels were significantly higher in OTA treated groups. It was concluded that production performance, pathological alterations and serum biochemical changes determined became more severe with increase in dietary levels of OTA.

  11. Preparation and storage stability of meat spread developed from spent hens

    Directory of Open Access Journals (Sweden)

    Ashish Kumar

    2015-05-01

    Full Text Available Aim: The present study was carried out to develop a meat spread as a healthier alternative to already existing meat products utilizing undervalued spent hen meat to add a new dimension to meat products. Materials and Methods: Carcasses were processed within 30 min of slaughter and conditioned at 4±1°C for about 24 h and then braised along with other ingredients to get the final product. The products were evaluated for proximate composition, peroxide values, pH, microbiological, and sensory qualities as per standard procedures. Results: The mean percent values for moisture, crude protein, ether extract, and total ash content of developed product were 58.75±0.32, 9.12±0.44, 11.19±0.16, and 2.35±0.17, respectively. No significant difference was observed for mean coliform and the yeast and mold counts with the progression of storage period, but samples differed significantly for mean pH, thiobarbituric acid and total viable plate count during storage of meat spread. A progressive decline in mean sensory scores was recorded along with the increase in storage time. Conclusion: The meat spread was found to be a good alternative to process the underutilized spent hens for its efficient utilization for product development.

  12. Preparation and storage stability of meat spread developed from spent hens.

    Science.gov (United States)

    Kumar, Ashish; Mendiratta, S K; Sen, Arup Ratan; Kandeepan, G; Talukder, Suman; Sharma, Heena; Soni, Arvind; Irshad, A; Kumar, Sanjay

    2015-05-01

    The present study was carried out to develop a meat spread as a healthier alternative to already existing meat products utilizing undervalued spent hen meat to add a new dimension to meat products. Carcasses were processed within 30 min of slaughter and conditioned at 4±1°C for about 24 h and then braised along with other ingredients to get the final product. The products were evaluated for proximate composition, peroxide values, pH, microbiological, and sensory qualities as per standard procedures. The mean percent values for moisture, crude protein, ether extract, and total ash content of developed product were 58.75±0.32, 9.12±0.44, 11.19±0.16, and 2.35±0.17, respectively. No significant difference was observed for mean coliform and the yeast and mold counts with the progression of storage period, but samples differed significantly for mean pH, thiobarbituric acid and total viable plate count during storage of meat spread. A progressive decline in mean sensory scores was recorded along with the increase in storage time. The meat spread was found to be a good alternative to process the underutilized spent hens for its efficient utilization for product development.

  13. Haematological and Biochemical Parameters during the Laying Period in Common Pheasant Hens Housed in Enhanced Cages

    Directory of Open Access Journals (Sweden)

    Petra Hrabčáková

    2014-01-01

    Full Text Available The development of selected haematological and biochemical parameters during the laying period was monitored in common pheasant hens housed in an enhanced cage system. The cages were enhanced by the addition of two perches and a shelter formed by strips of cloth hanging in the corner of the cage. The results showed significant changes in the haematological and biochemical parameters monitored during egg laying. At the time when laying capacity approached a maximum, a decrease was observed (P<0.05 in haematocrit, erythrocytes, and haemoglobin values, whereas monocytes, eosinophils, the heterophil/lymphocyte ratio, phosphorus, and calcium exhibited an increase (P<0.05. At the end of the laying period, an increase (P<0.05 was recorded in the count of leukocytes, heterophils, lymphocytes and basophils, the heterophil to lymphocyte ratio, and the concentrations of aspartate aminotransferase, cholesterol, phosphorus, and calcium, whereas lower values (P<0.05 were recorded for haematocrit and plasma total protein in comparison with the values of the indicators at the beginning of the laying period. The results provide new information about dynamic changes in selected haematological and biochemical parameters in clinically healthy common pheasant hens during the laying period.

  14. Computational protein structure modeling and analysis of UV-B stress protein in Synechocystis PCC 6803.

    Science.gov (United States)

    Rahman, Md Akhlaqur; Chaturvedi, Navaneet; Sinha, Sukrat; Pandey, Paras Nath; Gupta, Dwijendra Kumar; Sundaram, Shanthy; Tripathi, Ashutosh

    2013-01-01

    This study focuses on Ultra Violet stress (UVS) gene product which is a UV stress induced protein from cyanobacteria, Synechocystis PCC 6803. Three dimensional structural modeling of target UVS protein was carried out by homology modeling method. 3F2I pdb from Nostoc sp. PCC 7120 was selected as a suitable template protein structure. Ultimately, the detection of active binding regions was carried out for characterization of functional sites in modeled UV-B stress protein. The top five probable ligand binding sites were predicted and the common binding residues between target and template protein was analyzed. It has been validated for the first time that modeled UVS protein structure from Synechocystis PCC 6803 was structurally and functionally similar to well characterized UVS protein of another cyanobacterial species, Nostoc sp PCC 7120 because of having same structural motif and fold with similar protein topology and function. Investigations revealed that UVS protein from Synechocystis sp. might play significant role during ultraviolet resistance. Thus, it could be a potential biological source for remediation for UV induced stress.

  15. Metabolizable energy value of crude glycerin for laying hens

    Science.gov (United States)

    An experiment with laying hens was conducted to determine the apparent metabolizable energy-nitrogen corrected (AMEn) value of crude glycerin, a coproduct of biodiesel production. Crude glycerin (86.95% glycerol, 9.22% water, 0.03% methanol, 1.26% sodium, 3625 kcal/kg gross energy) was obtained from...

  16. Air samplings in a Campylobacter jejuni positive laying hen flock.

    Science.gov (United States)

    Ahmed, Marwa Fawzy El Metwaly; Schulz, Jochen; Hartung, Joerg

    2013-01-01

    The air in laying hen houses contains high concentrations of airborne bacteria. The numbers of these bacteria can be influenced by the efficiency of the chosen sampling method. In the presented study, AGI-30 Impingers and the Coriolis(®)µ air Sampler were compared in terms of their efficiency in sampling aerobic mesophilic bacteria in a laying hen house. Measurements were conducted in a laying hen flock with high prevalences of C. jejuni in order to investigate if culturable cells of this organism can also be detected by the applied methods. Airborne dust was also analyzed for the presence of C. jejuni specific DNA to assess the possible occurrence of non-culturable C. jejuni in the hen house air. The numbers of mesophilic airborne bacteria ranged from 8 × 10(4) - 2 × 10(6) CFU/m(-3) when sampled using AGI-30 Impingers, and from 2 × 10(5) - 4 × 10(6) CFU/m -3 when sampled using a Coriolis(®)µ air Sampler. The concentrations detected simultaneously by both devices correlated well (rPearson = 0.755), but the Coriolis(®)µ air Sampler showed a significantly higher sampling efficiency (phen house air, and in future it should be verified whether sampling stress of the air sampling methods could induce the non-culturable state.

  17. Requirement of the laying hen for apparent fecal digestible lysine

    NARCIS (Netherlands)

    Schutte, J.B.; Smink, W.

    1998-01-01

    A study was conducted to determine the requirement for lysine of a White Leghorn strain of hens with a body weight of approximately 1,600 g. Before starting the experiment, apparent fecal digestibility of amino acids of the basal diet was determined in an in vivo digestibility trial with six individ

  18. Feather pecking and related behavioural characteristics in laying hens

    NARCIS (Netherlands)

    Rodenburg, T.B.

    2003-01-01

    Feather pecking is a major welfare and economic problem in laying hens. It is characterised by pecking at- and pulling out of feathers of conspecifics. A bird's propensity to develop feather pecking may be related with other behavioural characteristics, such as reaction to frustration (the omission

  19. Housing system and laying hen strain impacts on egg microbiology

    Science.gov (United States)

    Alternative hen housing is becoming more commonplace in the egg market. However, a complete understanding of the implication of alternative housing systems on egg safety has not been achieved. The current study examines the impact of housing Hy-Line Brown, Hy-Line Silver Brown, and Barred Plymouth...

  20. THE PERFORMANCE OF LAYING HENS FED DIFFERENT CALCIUM SOURCE

    Directory of Open Access Journals (Sweden)

    S. Kismiati

    2014-10-01

    Full Text Available The research was aimed to evaluate the performance of laying hens fed different calcium sources.Two hundreds of Isa Brown laying hens were used in this study. The hens were raised in individualbattery cages units for 12 weeks. Four calcium source (limestone as a control, 5% limestone + 2.5%eggshells waste, 2.5% limestone + 5% eggshells waste and 7.5% eggshell waste were used in feedexperiment. A completely randomized design was applied, with 4 treatments and 5 replications. Eachexperimental unit consisted of 10 laying hens. The parameters measured were feed intake, proteinintake, calcium intake, phosphorus intake, egg production, egg weight and feed conversion ratio. Resultsof the research showed that the calcium source had significantly effect on performance productions. Theuse of eggshell waste 7.5% significantly increased the feed intake, calcium intake, phosphorus intake,egg production and egg weight except for feed conversion ratio. The conclusion of this research was thatthe use of eggshell waste as calcium source of feed resulted in better performance than using limestoneor mixed limestone with eggshell waste.

  1. Charged Analogues of Henning Knutsen Type Solutions in General Relativity

    Science.gov (United States)

    Gupta, Y. K.; Kumar, Sachin; Pratibha

    2011-11-01

    In the present article, we have found charged analogues of Henning Knutsen's interior solutions which join smoothly to the Reissner-Nordstrom metric at the pressure free interface. The solutions are singularity free and analyzed numerically with respect to pressure, energy-density and charge-density in details. The solutions so obtained also present the generalization of A.L. Mehra's solutions.

  2. One Hen: Teaching Elementary-Level Economics for Civic Engagement

    Science.gov (United States)

    Whitlock, Annie McMahon

    2013-01-01

    This dissertation is a qualitative case study focused on describing and analyzing the student and teacher experience with One Hen, a project-based learning unit specifically designed to teach civic engagement. In this study I address three questions: 1) Do fifth-grade students' knowledge and skills in economics change after participating in a…

  3. Chemical features, cholesterol and energy content of table hen eggs ...

    African Journals Online (AJOL)

    ... the eggs, and gross energy was calculated based on organic matter energy. All data were subjected to ANOVA statistical computation. The eggs produced in conventional cages compared with those laid in ... the cage-free system influenced hens to produce eggs with a higher nutritive value than in the other systems.

  4. The effects of propolis on antibody production by laying hens.

    Science.gov (United States)

    Freitas, J A; Vanat, N; Pinheiro, J W; Balarin, M R S; Sforcin, J M; Venancio, E J

    2011-06-01

    Propolis is a honeybee product showing several biological properties that enhance the immune response, depending on the concentration and intake period. Because propolis possesses an immunomodulatory action on mammals, the objective of our study was to investigate the effects of propolis on the humoral immune response of laying hens by evaluating antibody production. Laying hens (ISA Brown) were divided into 5 groups with 7 birds each. Group 1 was a nonimmunized control, whereas birds in group 2 were immunized intravenously with SRBC, and those in groups 3, 4, and 5 were treated intraperitoneally with propolis (2, 10, and 50 mg/kg, respectively) on 3 consecutive days and then inoculated intravenously with SRBC. Hematological and serological analyses were carried out on d 0, 3, and 38. Natural and specific antibody levels were determined by hemagglutination with rabbit red blood cells and SRBC, respectively. Propolis-treated birds (50 mg/kg) showed a significant decline in heterophils and in the heterophil:lymphocyte ratio. After SRBC immunization, significant increases in levels of IgG were observed in groups 4 and 5. Furthermore, higher levels of natural antibodies were observed in propolis-treated laying hens. The administration of propolis to laying hens increased the production of IgG specific to SRBC and natural antibodies, and could be used to increase antigen-specific antibody responses to vaccines.

  5. An integrated process for purification of lysozyme, ovalbumin, and ovomucoid from hen egg white.

    Science.gov (United States)

    Roy, Ipsita; Rao, M V S; Gupta, Munishwar N

    2003-10-01

    This article describes an integrated process for simultaneous purification of lysozyme, ovalbumin, and ovomucoid from hen egg white. The crude egg white extract was passed through a cation exchanger Streamline trade mark SP and the bound lysozyme was eluted with 5% ammonium carbonate, pH 9.0, containing 1 M NaCl after elution of avidin. This partially purified lysozyme was further purified 639-fold on dye-linked cellulose beads. Ovalbumin and ovomucoid did not bind to Streamline SP. Ovalbumin could be precipitated from this unbound fraction by 5% trichloroacetic acid, and ovomucoid was removed from the supernatant by precipitation with ethanol. The yields of lysozyme, ovomucoid, and ovalbumin were 77, 94, and 98%, respectively. All the purified proteins showed single bands on sodium dodecyl sulfate polyacrylamide gel electrophoresis. All the steps are easily scalable, and the process described here can be used for large-scale simultaneous purification of these proteins in the pure form.

  6. ANIMAL MODELS FOR PROTEIN RESPIRATORY SENSITIZERS

    Science.gov (United States)

    Protein induced respiratory hypersensitivity, particularly atopic disease in general, and allergic asthma in particular, has increased dramatically over the last several decades in the U.S. and other industrialized nations as a result of ill-defined changes in living conditions i...

  7. Corn Storage Protein - A Molecular Genetic Model

    Energy Technology Data Exchange (ETDEWEB)

    Messing, Joachim [Rutgers, The State University of New Jersey

    2013-05-31

    Corn is the highest yielding crop on earth and probably the most valuable agricultural product of the United States. Because it converts sun energy through photosynthesis into starch and proteins, we addressed energy savings by focusing on protein quality. People and animals require essential amino acids derived from the digestion of proteins. If proteins are relatively low in certain essential amino acids, the crop becomes nutritionally defective and has to be supplemented. Such deficiency affects meat and fish production and countries where corn is a staple. Because corn seed proteins have relatively low levels of lysine and methionine, a diet has to be supplemented with soybeans for the missing lysine and with chemically synthesized methionine. We therefore have studied genes expressed during maize seed development and their chromosomal organization. A critical technical requirement for the understanding of the molecular structure of genes and their positional information was DNA sequencing. Because of the length of sequences, DNA sequencing methods themselves were insufficient for this type of analysis. We therefore developed the so-called “DNA shotgun sequencing” strategy, where overlapping DNA fragments were sequenced in parallel and used to reconstruct large DNA molecules via overlaps. Our publications became the most frequently cited ones during the decade of 1981-1990 and former Associate Director of Science for the Office of Basic Energy Sciences Patricia M. Dehmer presented our work as one of the great successes of this program. A major component of the sequencing strategy was the development of bacterial strains and vectors, which were also used to develop the first biotechnology crops. These crops possessed new traits thanks to the expression of foreign genes in plants. To enable such expression, chimeric genes had to be constructed using our materials and methods by the industry. Because we made our materials and methods freely available to

  8. Ising Model Reprogramming of a Repeat Protein's Equilibrium Unfolding Pathway.

    Science.gov (United States)

    Millership, C; Phillips, J J; Main, E R G

    2016-05-08

    Repeat proteins are formed from units of 20-40 aa that stack together into quasi one-dimensional non-globular structures. This modular repetitive construction means that, unlike globular proteins, a repeat protein's equilibrium folding and thus thermodynamic stability can be analysed using linear Ising models. Typically, homozipper Ising models have been used. These treat the repeat protein as a series of identical interacting subunits (the repeated motifs) that couple together to form the folded protein. However, they cannot describe subunits of differing stabilities. Here we show that a more sophisticated heteropolymer Ising model can be constructed and fitted to two new helix deletion series of consensus tetratricopeptide repeat proteins (CTPRs). This analysis, showing an asymmetric spread of stability between helices within CTPR ensembles, coupled with the Ising model's predictive qualities was then used to guide reprogramming of the unfolding pathway of a variant CTPR protein. The designed behaviour was engineered by introducing destabilising mutations that increased the thermodynamic asymmetry within a CTPR ensemble. The asymmetry caused the terminal α-helix to thermodynamically uncouple from the rest of the protein and preferentially unfold. This produced a specific, highly populated stable intermediate with a putative dimerisation interface. As such it is the first step in designing repeat proteins with function regulated by a conformational switch. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Building toy models of proteins using coevolutionary information

    Science.gov (United States)

    Cheng, Ryan; Raghunathan, Mohit; Onuchic, Jose

    2015-03-01

    Recent developments in global statistical methodologies have advanced the analysis of large collections of protein sequences for coevolutionary information. Coevolution between amino acids in a protein arises from compensatory mutations that are needed to maintain the stability or function of a protein over the course of evolution. This gives rise to quantifiable correlations between amino acid positions within the multiple sequence alignment of a protein family. Here, we use Direct Coupling Analysis (DCA) to infer a Potts model Hamiltonian governing the correlated mutations in a protein family to obtain the sequence-dependent interaction energies of a toy protein model. We demonstrate that this methodology predicts residue-residue interaction energies that are consistent with experimental mutational changes in protein stabilities as well as other computational methodologies. Furthermore, we demonstrate with several examples that DCA could be used to construct a structure-based model that quantitatively agrees with experimental data on folding mechanisms. This work serves as a potential framework for generating models of proteins that are enriched by evolutionary data that can potentially be used to engineer key functional motions and interactions in protein systems. This research has been supported by the NSF INSPIRE award MCB-1241332 and by the CTBP sponsored by the NSF (Grant PHY-1427654).

  10. Initiating egg production in turkey breeder hens: thyroid hormone involvement.

    Science.gov (United States)

    Siopes, T D; Millam, J R; Steinman, M Q

    2010-10-01

    The role of thyroid hormones in the expression of photosensitivity-photorefractoriness in female turkeys was investigated through the use of an antithyroidal agent, 6-n-propyl-2-thiouracil (PTU). In experiment 1, females held continuously from hatch on long day lengths (16L:8D; LD) and fed 0.1% PTU from 0 to 16 wk, began laying eggs at 26 wk of age, peaking at 75% hen-day egg production by 29 wk, whereas controls initiated lay 3 wk earlier but only achieved less than 50% hen-day egg production. In experiment 2, PTU treatment from 10 to 18 wk severely suppressed plasma triiodothyronine and thyroxine, as confirmed by RIA. Egg production of PTU and control hens held on LD from hatch began by 23 wk, with PTU hens reaching a substantially greater rate of lay than controls. Eggs were smaller initially in both treatments but exceeded 75 g by 28 wk. In experiment 3, recycled hens on short day lengths (8L:16D) received PTU for 2 wk before LD and 12 wk thereafter; a subset of these hens was killed after 48 h of LD for immunohistochemical analysis of fos-related antigen (FRA) expression in the tuberal hypothalamus as a marker of photoinduced neuronal activity. The PTU treatment completely forestalled egg production until its withdrawal; egg production then rose sharply to control levels before resuming, along with controls, a typical seasonal decline. The PTU treatment did not impair photoinduced FRA expression. Together, these results demonstrate the following: 1) that a period of pharmacological suppression of triiodothyronine and thyroxine can substitute for short day exposure in conferring photosensitivity on juvenile-aged turkeys (and is actually superior to short day exposure), 2) that reproductive development does not limit egg production of turkey hens photostimulated as young as approximately 20 wk of age, and 3) that effects of thyroid suppression on photostimulation lie downstream of photoinduced FRA expression. Taken together, these results suggest that there is

  11. Shear stress-mediated refolding of proteins from aggregates and inclusion bodies

    OpenAIRE

    Yuan, TZ; Ormonde, CFG; Kudlacek, ST; Kunche, S; Smith, JN; Brown, WA; Pugliese, KM; Olsen, TJ; Iftikhar, M; Raston, CL; Weiss, GA

    2015-01-01

    © 2015 Wiley-VCH Verlag GmbH & Co. KGaA. Recombinant protein overexpression of large proteins in bacteria often results in insoluble and misfolded proteins directed to inclusion bodies. We report the application of shear stress in micrometer-wide, thin fluid films to refold boiled hen egg white lysozyme, recombinant hen egg white lysozyme, and recombinant caveolin-1. Furthermore, the approach allowed refolding of a much larger protein, cAMP-dependent protein kinase A (PKA). The reported metho...

  12. Immunization of chickens with quail and turkey perivitelline membrane proteins: production of antibodies and their effects on fertility.

    Science.gov (United States)

    Kapoor, P; Compton, M M; Howarth, B

    2000-02-01

    The cross-reactivity of antibodies developed against zona pellucida proteins and their subsequent deleterious effect on fertility in heterologous species is well documented. However, similar investigations have not been undertaken in avian species. In Experiment 1, White Leghorn hens were immunized with intact germinal discs (GD) of quail and chickens. Chicken GD proteins did not elicit an immune response in chicken hens, whereas quail GD proteins were highly immunogenic. Anti-quail GD antibodies did not bind with chicken inner perivitelline membrane (IPM) proteins as determined by immunoblot analysis. To examine the fertility of immunized hens, artificial insemination was performed at weekly intervals for 4 wk following the booster immunization. No significant differences were detected in fertility or hatchability of immunized hens when compared with unimmunized control hens. In Experiment 2, White Leghorn hens were immunized with intact turkey GD, solubilized turkey perivitelline membrane (PM) modified with dinitrophenol (DNP), and solubilized chicken IPM modified with DNP. High titers of antibodies were detected against the turkey GD and the DNP-modified turkey PM proteins. A weak immune response was observed in hens immunized with modified chicken IPM proteins. The fertility and hatchability of eggs laid by immunized hens, however, were not significantly different from those of unimmunized hens. Antibodies from immunized hens were further analyzed using an in vitro assay that assesses sperm penetration of intact IPM. Sperm penetration of intact IPM was inhibited to the same extent when IPM was preincubated with preimmune as well as anti-PM immunoglobulins. Collectively, these results suggested that the antibodies developed in these hens did not cross-react with the chicken IPM proteins involved in sperm-egg interaction and thus did not influence the fertility.

  13. A bespoke management package can reduce levels of injurious pecking in loose-housed laying hen flocks.

    Science.gov (United States)

    Lambton, S L; Nicol, C J; Friel, M; Main, D C J; McKinstry, J L; Sherwin, C M; Walton, J; Weeks, C A

    2013-04-20

    This study investigated the protective effects of an on-farm management package designed to reduce injurious pecking (IP) in loose-housed laying hens. A systematic review of scientific literature generated 46 potentially protective management strategies. Bespoke management packages were designed for treatment flocks (TF) using these management strategies. IP in 53 TFs was compared with IP in 47 control flocks (CF) where the management package was not employed. Scoring of plumage damage (PD) and observations of gentle and severe feather pecking (GFP; SFP), and vent and cannibalistic pecking (VP) were completed, and management strategy use was recorded, at 20, 30 and 40 weeks of age. Differences between treatment and CF were examined using multilevel modelling. Compared with CF, TF employed more management strategies (Playing hen flocks.

  14. Developing algorithms for predicting protein-protein interactions of homology modeled proteins.

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Shawn Bryan; Sale, Kenneth L.; Faulon, Jean-Loup Michel; Roe, Diana C.

    2006-01-01

    The goal of this project was to examine the protein-protein docking problem, especially as it relates to homology-based structures, identify the key bottlenecks in current software tools, and evaluate and prototype new algorithms that may be developed to improve these bottlenecks. This report describes the current challenges in the protein-protein docking problem: correctly predicting the binding site for the protein-protein interaction and correctly placing the sidechains. Two different and complementary approaches are taken that can help with the protein-protein docking problem. The first approach is to predict interaction sites prior to docking, and uses bioinformatics studies of protein-protein interactions to predict theses interaction site. The second approach is to improve validation of predicted complexes after docking, and uses an improved scoring function for evaluating proposed docked poses, incorporating a solvation term. This scoring function demonstrates significant improvement over current state-of-the art functions. Initial studies on both these approaches are promising, and argue for full development of these algorithms.

  15. Storage stability of a commercial hen egg yolk powder in dry and intermediate-moisture food matrices.

    Science.gov (United States)

    Rao, Qinchun; Fisher, Mary Catherine; Guo, Mufan; Labuza, Theodore P

    2013-09-11

    Quality loss in intermediate-moisture foods (IMF) such as high-protein nutrition bars (HPNB) in the form of hardening, nonenzymatic browning, and free amino group loss is a general concern for the manufacturers. To measure the extent of quality loss over time in terms of these negative attributes, through changing the ratio by weight between two commercial spray-dried hen egg powders, egg white (DEW) and egg yolk (DEY), the storage stability of 10 IMF systems (water activity (aw) ∼ 0.6) containing 5% glycerol, 10% shortening, 35% protein, and 50% sweetener (either maltitol or 50% high-fructose corn syrup/50% corn syrup (HFCS/CS)) were studied. Additionally, the storage stability of the DEY powder itself was investigated. Overall, during storage at different temperatures (23, 35, and 45 °C), the storage stability of DEY in dry and IMF matrices was mainly controlled by the coaction of three chemical reactions (disulfide bond interaction, Maillard reaction, and lipid oxidation). The results showed that by replacing 25% of DEW in an IMF model system with DEY, the rate of bar hardening was significantly lower than that of the models with only DEW at all temperatures due to the softening effect of the fat in DEY. Furthermore, the use of maltitol instead of HFCS/CS in all bar systems not only resulted in decreased hardness but also drastically decreased the change in the total color difference (ΔE*). Interestingly, there was no significant loss of free amino groups in the maltitol systems at any DEW/DEY ratio.

  16. On the characterization of intermediates in the isodesmic aggregation pathway of hen lysozyme at alkaline pH.

    Directory of Open Access Journals (Sweden)

    Vijay Kumar Ravi

    Full Text Available Protein aggregation leading to formation of amyloid fibrils is a symptom of several diseases like Alzheimer's, type 2 diabetes and so on. Elucidating the poorly understood mechanism of such phenomena entails the difficult task of characterizing the species involved at each of the multiple steps in the aggregation pathway. It was previously shown by us that spontaneous aggregation of hen-eggwhite lysozyme (HEWL at room temperature in pH 12.2 is a good model to study aggregation. Here in this paper we investigate the growth kinetics, structure, function and dynamics of multiple intermediate species populating the aggregation pathway of HEWL at pH 12.2. The different intermediates were isolated by varying the HEWL monomer concentration in the 300 nM-0.12 mM range. The intermediates were characterized using techniques like steady-state and nanosecond time-resolved fluorescence, atomic force microscopy and dynamic light scattering. Growth kinetics of non-fibrillar HEWL aggregates were fitted to the von Bertalanffy equation to yield a HEWL concentration independent rate constant (k = (6.6 ± 0.6 × 10(-5 s(-1. Our results reveal stepwise changes in size, molecular packing and enzymatic activity among growing HEWL aggregates consistent with an isodesmic aggregation model. Formation of disulphide bonds that crosslink the monomers in the aggregate appear as a unique feature of this aggregation. AFM images of multiple amyloid fibrils emanating radially from amorphous aggregates directly confirmed that on-pathway fibril formation was feasible under isodesmic polymerization. The isolated HEWL aggregates are revealed as polycationic protein nanoparticles that are robust at neutral pH with ability to take up non-polar molecules like ANS.

  17. Hidden Markov models for prediction of protein features

    DEFF Research Database (Denmark)

    Bystroff, Christopher; Krogh, Anders

    2008-01-01

    Hidden Markov Models (HMMs) are an extremely versatile statistical representation that can be used to model any set of one-dimensional discrete symbol data. HMMs can model protein sequences in many ways, depending on what features of the protein are represented by the Markov states. For protein...... structure prediction, states have been chosen to represent either homologous sequence positions, local or secondary structure types, or transmembrane locality. The resulting models can be used to predict common ancestry, secondary or local structure, or membrane topology by applying one of the two standard...... algorithms for comparing a sequence to a model. In this chapter, we review those algorithms and discuss how HMMs have been constructed and refined for the purpose of protein structure prediction....

  18. Loopholes and missing links in protein modeling.

    Science.gov (United States)

    Rossi, Karen A; Weigelt, Carolyn A; Nayeem, Akbar; Krystek, Stanley R

    2007-09-01

    This paper provides an unbiased comparison of four commercially available programs for loop sampling, Prime, Modeler, ICM, and Sybyl, each of which uses a different modeling protocol. The study assesses the quality of results and examines the relative strengths and weaknesses of each method. The set of loops to be modeled varied in length from 4-12 amino acids. The approaches used for loop modeling can be classified into two methodologies: ab initio loop generation (Modeler and Prime) and database searches (Sybyl and ICM). Comparison of the modeled loops to the native structures was used to determine the accuracy of each method. All of the protocols returned similar results for short loop lengths (four to six residues), but as loop length increased, the quality of the results varied among the programs. Prime generated loops with RMSDs modeled loops.

  19. Cage Versus Noncage Laying-Hen Housings: Worker Respiratory Health.

    Science.gov (United States)

    Mitchell, Diane; Arteaga, Veronica; Armitage, Tracey; Mitloehner, Frank; Tancredi, Daniel; Kenyon, Nicholas; Schenker, Marc

    2015-01-01

    The objective of this study was to compare respiratory health of poultry workers in conventional cage, enriched cage and aviary layer housing on a single commercial facility, motivated by changing requirements for humane housing of hens. Three workers were randomly assigned daily, one to each of conventional cage, enriched cage, and aviary housing in a crossover repeated-measures design for three observation periods (for a total of 123 worker-days, eight different workers). Workers' exposure to particles were assessed (Arteaga et al. J Agromedicine. 2015;20:this issue) and spirometry, exhaled nitric oxide, respiratory symptoms, and questionnaires were conducted pre- and post-shift. Personal exposures to particles and endotoxin were significantly higher in the aviary than the other housings (Arteaga et al., 2015). The use of respiratory protection was high; the median usage was 70% of the shift. Mixed-effects multivariate regression models of respiratory cross-shift changes were marginally significant, but the aviary system consistently posted the highest decrements for forced expiratory volume in 1 and 6 seconds (FEV1 and FEV6) compared with the enriched or conventional housing. The adjusted mean difference in FEV1 aviary - enriched cage housing was -47 mL/s, 95% confidence interval (CI): (-99 to 4.9), P = .07. Similarly, for FEV6, aviary - conventional housing adjusted mean difference was -52.9 mL/6 s, 95% CI: (-108 to 2.4), P = .06. Workers adopting greater than median use of respiratory protection were less likely to exhibit negative cross-shift pulmonary function changes. Although aviary housing exposed workers to significantly higher respiratory exposures, cross-shift pulmonary function changes did not differ significantly between houses. Higher levels of mask use were protective; poultry workers should wear respiratory protection as appropriate to avoid health decrements.

  20. Protein secondary structure analysis with a coarse-grained model

    OpenAIRE

    Kneller, Gerald R.; Hinsen, Konrad

    2014-01-01

    The paper presents a geometrical model for protein secondary structure analysis which uses only the positions of the $C_{\\alpha}$-atoms. We construct a space curve connecting these positions by piecewise polynomial interpolation and describe the folding of the protein backbone by a succession of screw motions linking the Frenet frames at consecutive $C_{\\alpha}$-positions. Using the ASTRAL subset of the SCOPe data base of protein structures, we derive thresholds for the screw parameters of se...

  1. Modeling protein network evolution under genome duplication and domain shuffling

    Directory of Open Access Journals (Sweden)

    Isambert Hervé

    2007-11-01

    Full Text Available Abstract Background Successive whole genome duplications have recently been firmly established in all major eukaryote kingdoms. Such exponential evolutionary processes must have largely contributed to shape the topology of protein-protein interaction (PPI networks by outweighing, in particular, all time-linear network growths modeled so far. Results We propose and solve a mathematical model of PPI network evolution under successive genome duplications. This demonstrates, from first principles, that evolutionary conservation and scale-free topology are intrinsically linked properties of PPI networks and emerge from i prevailing exponential network dynamics under duplication and ii asymmetric divergence of gene duplicates. While required, we argue that this asymmetric divergence arises, in fact, spontaneously at the level of protein-binding sites. This supports a refined model of PPI network evolution in terms of protein domains under exponential and asymmetric duplication/divergence dynamics, with multidomain proteins underlying the combinatorial formation of protein complexes. Genome duplication then provides a powerful source of PPI network innovation by promoting local rearrangements of multidomain proteins on a genome wide scale. Yet, we show that the overall conservation and topology of PPI networks are robust to extensive domain shuffling of multidomain proteins as well as to finer details of protein interaction and evolution. Finally, large scale features of direct and indirect PPI networks of S. cerevisiae are well reproduced numerically with only two adjusted parameters of clear biological significance (i.e. network effective growth rate and average number of protein-binding domains per protein. Conclusion This study demonstrates the statistical consequences of genome duplication and domain shuffling on the conservation and topology of PPI networks over a broad evolutionary scale across eukaryote kingdoms. In particular, scale

  2. Assessment of the effect of housing on feather damage in laying hens using IR thermography.

    Science.gov (United States)

    Pichová, K; Bilčík, B; Košt'ál, L'

    2017-04-01

    Plumage damage represents one of the animal-based measures of laying hens welfare. Damage occurs predominantly due to age, environment and damaging pecking. IR thermography, due to its non-invasiveness, objectivity and repeatability is a promising alternative to feather damage scoring systems such as the system included in the Welfare Quality ® assessment protocol for poultry. The aim of this study was to apply IR thermography for the assessment of feather damage in laying hens kept in two housing systems and to compare the results with feather scoring. At the start of the experiment, 16-week-old laying hens (n=30) were divided into two treatments such as deep litter pen and enriched cage. During 4 months, feather damage was assessed regularly in 2-week intervals. One more single assessment was done nine and a half months after the start of the experiment. The feather damage on four body regions was assessed by scoring and IR thermography: head and neck, back and rump, belly, and underneck and breast. Two variables obtained by IR thermography were used: the difference between the body surface temperature and ambient temperature (ΔTB) and the proportion of featherless areas, which were defined as areas with a temperature >33.5°C. Data were analyzed using a GLM model. The effects of housing, time, region and their interactions on feather damage, measured by the feather scoring and by both IR thermography measures, were all significant (P<0.001). The ΔTB in all assessed regions correlated positively with the feather score. Feather scoring revealed higher damage in enriched cages compared with deep litter pens starting from week 6 of the experiment on the belly and back and rump regions, whereas ΔTB from week 6 in the belly and from week 8 on the back and rump region. The proportion of featherless areas in the belly region differed significantly between the housings from week 8 of the experiment and on the back and rump region from week 12. The IR thermography

  3. Ventilation rates in large commercial layer hen houses with two-year continuous monitoring.

    Science.gov (United States)

    Chai, L; Ni, J-Q; Diehl, C A; Kilic, I; Heber, A J; Chen, Y; Cortus, E L; Bogan, B W; Lim, T T; Ramirez-Dorronsoro, J-C; Chen, L

    2012-01-01

    1. Ventilation controls the indoor environment and is critical for poultry production and welfare. Ventilation is also crucial for assessing aerial pollutant emissions from the poultry industry. Published ventilation data for commercial layer houses have been limited, and are mostly based on short-term studies, mainly because monitoring airflow from large numbers of fans is technically challenging. 2. A two-year continuous ventilation monitoring trial was conducted at two commercial manure belt houses (A and B), each with 250 000 layers and 88 130-cm exhaust fans. All the fans were individually monitored with fan rotational speed sensors or vibration sensors. Differential static pressures across the house walls were also measured. Three fan performance assessment methods were applied periodically to determine fan degradations. Fan models were developed to calculate house ventilations. 3. A total of 693 and 678 complete data days, each containing >16 h of valid ventilation data, were obtained in houses A and B, respectively. The two-year mean ventilation rates of houses A and B were 2·08 and 2·10 m(3) h(-1) hen(-1), corresponding to static pressures of -36·5 and -48·9 Pa, respectively. For monthly mean ventilation, the maximum rates were 4·87 and 5·01 m(3) h(-1) hen(-1) in July 2008, and the minimum were 0·59 and 0·81 m(3) h(-1) hen(-1) in February 2008, for houses A and B, respectively. 4. The two-year mean ventilation rates were similar to those from a survey in Germany and a 6-month study in Indiana, USA, but were much lower than the 8·4 and 6·2 m(3) h(-1) hen(-1) from a study in Italy. The minimum monthly mean ventilation rates were similar to the data obtained in winter in Canada, but were lower than the minimum ventilation suggested in the literature. The lower static pressure in house B required more ventilation energy input. The two houses, although identical, demonstrated differences in indoor environment controls

  4. An Integrated Framework Advancing Membrane Protein Modeling and Design.

    Directory of Open Access Journals (Sweden)

    Rebecca F Alford

    2015-09-01

    Full Text Available Membrane proteins are critical functional molecules in the human body, constituting more than 30% of open reading frames in the human genome. Unfortunately, a myriad of difficulties in overexpression and reconstitution into membrane mimetics severely limit our ability to determine their structures. Computational tools are therefore instrumental to membrane protein structure prediction, consequently increasing our understanding of membrane protein function and their role in disease. Here, we describe a general framework facilitating membrane protein modeling and design that combines the scientific principles for membrane protein modeling with the flexible software architecture of Rosetta3. This new framework, called RosettaMP, provides a general membrane representation that interfaces with scoring, conformational sampling, and mutation routines that can be easily combined to create new protocols. To demonstrate the capabilities of this implementation, we developed four proof-of-concept applications for (1 prediction of free energy changes upon mutation; (2 high-resolution structural refinement; (3 protein-protein docking; and (4 assembly of symmetric protein complexes, all in the membrane environment. Preliminary data show that these algorithms can produce meaningful scores and structures. The data also suggest needed improvements to both sampling routines and score functions. Importantly, the applications collectively demonstrate the potential of combining the flexible nature of RosettaMP with the power of Rosetta algorithms to facilitate membrane protein modeling and design.

  5. Effects of Furnished Cage Type on Behavior and Welfare of Laying Hens.

    Science.gov (United States)

    Li, Xiang; Chen, Donghua; Li, Jianhong; Bao, Jun

    2016-06-01

    This study was conducted to compare the effects of layout of furniture (a perch, nest, and sandbox) in cages on behavior and welfare of hens. Two hundred and sixteen Hyline Brown laying hens were divided into five groups (treatments) with four replicates per group: small furnished cages (SFC), medium furnished cages type I (MFC-I), medium furnished cages type II (MFC-II), and medium furnished cages type III (MFC-III) and conventional cages (CC). The experiment started at 18 week of age and finished at 52 week of age. Hens' behaviors were filmed during the following periods: 8:00 to 10:00; 13:00 to 14:00; 16:00 to 17:00 on three separate days and two hens from each cage were measured for welfare parameters at 50 wk of age. The results showed that feeding and laying of all hens showed no effect by cage type (p>0.05), and the hens in the furnished cages had significantly lower standing and higher walking than CC hens (p0.05). The hens in MFC-I, -II, and -III showed a significant higher socializing behavior than SFC and CC (p<0.05). The lowest perching was for the hens in SFC and the highest perching found for the hens in MFC-III. Overall, the hens in CC showed poorer welfare conditions than the furnished cages, in which the feather condition score, gait score and tonic immobility duration of the hens in CC was significantly higher than SFC, MFC-I, MFC-II, and MFC-III (p<0.05). In conclusion, the furnished cage design affected both behavior and welfare states of hens. Overall, MFC-III cage design was better than SFC, MFC-I, and MFC-II cage designs.

  6. New insights on the complex planetary nebula Hen 2-113

    CERN Document Server

    Lagadec, E; Matsuura, M; De Marco, O; De Pacheco, J A F; Zijlstra, A; Acker, A; Clayton, G; Lagadec, Eric; Chesneau, Olivier; Matsuura, Mikako; Marco, Orsola De; Pacheco, Jose Antonio De Freitas; Zijlstra, Albert; Acker, Agn\\`{e}s; Clayton, Geoffrey

    2005-01-01

    We report infrared observations of the planetary nebula Hen 2-113 obtained with VLT/NACO, VLTI/MIDI, VLT/ISAAC and TIMMI at the ESO 3.6m. Hen 2-113 exhibits a clear ring-like structure superimposed to a more diffuse environment visible in the L' (3.8$\\mu$m), M' (4.78$\\mu$m) and 8.7$\\mu$m bands. No clear core at 8.7$\\mu$m and no fringes through the N band could be detected for this object with MIDI. A qualitative interpretation of the object structure is proposed using a diabolo-like geometrical model. The PAH content of the nebula was also studied with ISAAC and TIMMI observations. This indicates that the PAHs are mostly concentrated towards the lobes of the diabolo and the bipolar lobes of the nebula. In L' band, a void $0.3\\arcsec$ in diameter was discovered with NACO around the central source. The L' and M' fluxes from the central source were derived from NACO data indicating an important infrared excess with respect to the expected stellar emission based on stellar models and short wavelength data. The ob...

  7. Model systems for understanding absorption tuning by opsin proteins

    DEFF Research Database (Denmark)

    Nielsen, Mogens Brøndsted

    2009-01-01

    This tutorial review reports on model systems that have been synthesised and investigated for elucidating how opsin proteins tune the absorption of the protonated retinal Schiff base chromophore. In particular, the importance of the counteranion is highlighted. In addition, the review advocates...... is avoided, and it becomes clear that opsin proteins induce blueshifts in the chromophore absorption rather than redshifts....

  8. Potential and utilization of Indigofera sp shoot leaf meal as soybean meal substitution in laying hen diets

    Directory of Open Access Journals (Sweden)

    Rizki Palupi

    2014-10-01

    Full Text Available The objective of this study was to determine the potential of Indigofera sp shoot leaf meal to substitute soybean meal in poultry diet. One hundred and sixty laying hens of Isa Brown strain, at 30 weeks old were used in this study and kept in individual cages. A Randomized Completely Design was applied with four treatments and four replications. The treatments were four levels of soybean meal protein substitution by Indigofera sp shoot meal protein in the diets: The level were 0% (R0, 15% (R1, 30% (R2 and 45% (R3. Eggs were collected daily and were evaluated on: weight, shell, albumen, yolk, intensity of yolk and haugh unit. Results showed that the nutrients content of Indigofera sp shoot leaf meal were crude protein 28.98%, crude fat 3.30%, crude fiber 8.49%, calcium 0.52% and phosphorus content was 0.34%. Indigofera sp shoot leaf meal contained a complete amino acids. The vitamin A and ß-carotene were high, i.e 3828.79 IU/100g and 507.6 mg/kg, respectively. It is concluded that Indigofera sp shoot leaf meal is potential to be used as an alternative source of protein. Substitute 45% soybean meal protein with Indigofera sp shoot leaf meal in laying hen diets increase egg quality and increase intensity of yolk colour to 55.88%.

  9. Chemical abundance analysis of symbiotic giants - III. V694 Mon, CD-36 8436, WRAY 16-202, Hen 3-1213, V455 Sco, and Hen 2-247

    CERN Document Server

    Galan, Cezary; Hinkle, Kenneth H

    2014-01-01

    The elemental abundances of symbiotic giants are essential to address the role of chemical composition in the evolution of symbiotic binaries, to map their parent population, and to trace their mass transfer history. However,the number of symbiotic giants with fairly well determined photospheric composition is still insufficient for statistical analyses. This is the third in a series of papers on the chemical composition of symbiotic giants determined from high resolution (R 50000), near-IR spectra. We present results here for the giant star in the V694 Mon, CD-36 8436, WRAY 16-202, Hen 3-1213, V455 Sco, and Hen 2-247 systems. Spectrum synthesis employing standard local thermal equilibrium (LTE) analysis and atmosphere models were used to obtain photospheric abundances of CNO and elements around the iron peak (Sc, Ti, Fe, and Ni). Our analysis reveals metallicities from slightly super-solar for V455 Sco ([Fe/H] +0.3 dex), near solar for WRAY 16-202 and Hen 2-247, slightly sub-solar for V694 Mon and CD-36 8436...

  10. Dynamical model of the kinesin protein motor

    CERN Document Server

    Nesterov, Alexander I; Ramírez, Mónica F

    2016-01-01

    We model and simulate the stepping dynamics of the kinesin motor including electric and mechanical forces, environmental noise, and the complicated potentials produced by tracking and neighboring protofilaments. Our dynamical model supports the hand-over-hand mechanism of the kinesin stepping. Our theoretical predictions and numerical simulations include the off-axis displacements of the kinesin heads while the steps are performed. The results obtained are in a good agreement with recent experiments on the kinesin dynamics.

  11. A coarse grain model for protein-surface interactions

    Science.gov (United States)

    Wei, Shuai; Knotts, Thomas A.

    2013-09-01

    The interaction of proteins with surfaces is important in numerous applications in many fields—such as biotechnology, proteomics, sensors, and medicine—but fundamental understanding of how protein stability and structure are affected by surfaces remains incomplete. Over the last several years, molecular simulation using coarse grain models has yielded significant insights, but the formalisms used to represent the surface interactions have been rudimentary. We present a new model for protein surface interactions that incorporates the chemical specificity of both the surface and the residues comprising the protein in the context of a one-bead-per-residue, coarse grain approach that maintains computational efficiency. The model is parameterized against experimental adsorption energies for multiple model peptides on different types of surfaces. The validity of the model is established by its ability to quantitatively and qualitatively predict the free energy of adsorption and structural changes for multiple biologically-relevant proteins on different surfaces. The validation, done with proteins not used in parameterization, shows that the model produces remarkable agreement between simulation and experiment.

  12. Comparative Study of Elastic Network Model and Protein Contact Network for Protein Complexes: The Hemoglobin Case

    Directory of Open Access Journals (Sweden)

    Guang Hu

    2017-01-01

    Full Text Available The overall topology and interfacial interactions play key roles in understanding structural and functional principles of protein complexes. Elastic Network Model (ENM and Protein Contact Network (PCN are two widely used methods for high throughput investigation of structures and interactions within protein complexes. In this work, the comparative analysis of ENM and PCN relative to hemoglobin (Hb was taken as case study. We examine four types of structural and dynamical paradigms, namely, conformational change between different states of Hbs, modular analysis, allosteric mechanisms studies, and interface characterization of an Hb. The comparative study shows that ENM has an advantage in studying dynamical properties and protein-protein interfaces, while PCN is better for describing protein structures quantitatively both from local and from global levels. We suggest that the integration of ENM and PCN would give a potential but powerful tool in structural systems biology.

  13. A least square method based model for identifying protein complexes in protein-protein interaction network.

    Science.gov (United States)

    Dai, Qiguo; Guo, Maozu; Guo, Yingjie; Liu, Xiaoyan; Liu, Yang; Teng, Zhixia

    2014-01-01

    Protein complex formed by a group of physical interacting proteins plays a crucial role in cell activities. Great effort has been made to computationally identify protein complexes from protein-protein interaction (PPI) network. However, the accuracy of the prediction is still far from being satisfactory, because the topological structures of protein complexes in the PPI network are too complicated. This paper proposes a novel optimization framework to detect complexes from PPI network, named PLSMC. The method is on the basis of the fact that if two proteins are in a common complex, they are likely to be interacting. PLSMC employs this relation to determine complexes by a penalized least squares method. PLSMC is applied to several public yeast PPI networks, and compared with several state-of-the-art methods. The results indicate that PLSMC outperforms other methods. In particular, complexes predicted by PLSMC can match known complexes with a higher accuracy than other methods. Furthermore, the predicted complexes have high functional homogeneity.

  14. fast_protein_cluster: parallel and optimized clustering of large-scale protein modeling data.

    Science.gov (United States)

    Hung, Ling-Hong; Samudrala, Ram

    2014-06-15

    fast_protein_cluster is a fast, parallel and memory efficient package used to cluster 60 000 sets of protein models (with up to 550 000 models per set) generated by the Nutritious Rice for the World project. fast_protein_cluster is an optimized and extensible toolkit that supports Root Mean Square Deviation after optimal superposition (RMSD) and Template Modeling score (TM-score) as metrics. RMSD calculations using a laptop CPU are 60× faster than qcprot and 3× faster than current graphics processing unit (GPU) implementations. New GPU code further increases the speed of RMSD and TM-score calculations. fast_protein_cluster provides novel k-means and hierarchical clustering methods that are up to 250× and 2000× faster, respectively, than Clusco, and identify significantly more accurate models than Spicker and Clusco. fast_protein_cluster is written in C++ using OpenMP for multi-threading support. Custom streaming Single Instruction Multiple Data (SIMD) extensions and advanced vector extension intrinsics code accelerate CPU calculations, and OpenCL kernels support AMD and Nvidia GPUs. fast_protein_cluster is available under the M.I.T. license. (http://software.compbio.washington.edu/fast_protein_cluster) © The Author 2014. Published by Oxford University Press.

  15. Modelling Protein Dynamics on the Microsecond Time Scale

    DEFF Research Database (Denmark)

    Siuda, Iwona Anna

    Recent years have shown an increase in coarse-grained (CG) molecular dynamics simulations, providing structural and dynamic details of large proteins and enabling studies of self-assembly of biological materials. It is not easy to acquire such data experimentally, and access is also still limited...... in atomistic simulations. During her PhD studies, Iwona Siuda used MARTINI CG models to study the dynamics of different globular and membrane proteins. In several cases, the MARTINI model was sufficient to study conformational changes of small, purely alpha-helical proteins. However, in studies of larger...... family....

  16. Modeling the Tensile Properties of Soybean Protein Yarns

    Institute of Scientific and Technical Information of China (English)

    石风俊; 崔世忠

    2003-01-01

    The tensile properties of a series of soybean protein yarns are tested in USTER THINKPAID Ⅲ.A nonlinear viscoelastic model has been proposed to describe the tensile behavior of soybean protein yarns.The model is composed of a Maxwell element,a linear spring and a nonlinear spring.The tensile properties of soybean protein yarn are analyzed.The stress-strain curves of the yarns are fitted.The average breaking tenacity and specific work of rupture are calculated using the average breaking strain.Comparisons indicate that theoretical predictions conform the experimental results very well.

  17. A comparison of transmission characteristics of Salmonella enterica serovar Enteritidis between pair-housed and group-housed laying hens

    Directory of Open Access Journals (Sweden)

    Thomas Ekelijn

    2011-02-01

    Full Text Available Abstract Human cases of bacterial gastro-enteritis are often caused by the consumption of eggs contaminated with Salmonella species, mainly Salmonella enterica serovar Enteriditis (Salmonella Enteritidis. To reduce human exposure, in several countries worldwide surveillance programmes are implemented to detect colonized layer flocks. The sampling schemes are based on the within-flock prevalence, and, as this changes over time, knowledge of the within-flock dynamics of Salmonella Enteritidis is required. Transmission of Salmonella Enteritidis has been quantified in pairs of layers, but the question is whether the dynamics in pairs is comparable to transmission in large groups, which are more representative for commercial layer flocks. The aim of this study was to compare results of transmission experiments between pairs and groups of laying hens. Experimental groups of either 2 or 200 hens were housed at similar densities, and 1 or 4 hens were inoculated with Salmonella Enteritidis, respectively. Excretion was monitored by regularly testing of fecal samples for the presence of Salmonella Enteritidis. Using mathematical modeling, the group experiments were simulated with transmission parameter estimates from the pairwise experiments. Transmission of the bacteria did not differ significantly between pairs or groups. This finding suggests that the transmission parameter estimates from small-scale experiments might be extrapolated to the field situation.

  18. A comparison of transmission characteristics of Salmonella enterica serovar Enteritidis between pair-housed and group-housed laying hens.

    Science.gov (United States)

    Thomas, Ekelijn; Bouma, Annemarie; Klinkenberg, Don

    2011-02-23

    Human cases of bacterial gastro-enteritis are often caused by the consumption of eggs contaminated with Salmonella species, mainly Salmonella enterica serovar Enteriditis (Salmonella Enteritidis). To reduce human exposure, in several countries worldwide surveillance programmes are implemented to detect colonized layer flocks. The sampling schemes are based on the within-flock prevalence, and, as this changes over time, knowledge of the within-flock dynamics of Salmonella Enteritidis is required. Transmission of Salmonella Enteritidis has been quantified in pairs of layers, but the question is whether the dynamics in pairs is comparable to transmission in large groups, which are more representative for commercial layer flocks. The aim of this study was to compare results of transmission experiments between pairs and groups of laying hens. Experimental groups of either 2 or 200 hens were housed at similar densities, and 1 or 4 hens were inoculated with Salmonella Enteritidis, respectively. Excretion was monitored by regularly testing of fecal samples for the presence of Salmonella Enteritidis. Using mathematical modeling, the group experiments were simulated with transmission parameter estimates from the pairwise experiments. Transmission of the bacteria did not differ significantly between pairs or groups. This finding suggests that the transmission parameter estimates from small-scale experiments might be extrapolated to the field situation.

  19. The unfolded protein response and translation attenuation: a modelling approach.

    Science.gov (United States)

    Trusina, A; Tang, C

    2010-10-01

    Unfolded protein response (UPR) is a stress response to increased levels of unfolded proteins in the endoplasmic reticulum (ER). To deal with this stress, all eukaryotic cells share a well-conserved strategy--the upregulation of chaperons and proteases to facilitate protein folding and to degrade the misfolded proteins. For metazoans, however, an additional and seemingly redundant strategy has been evolved--translation attenuation (TA) of proteins targeted to the ER via the protein kinase PERK pathway. PERK is essential in secretory cells, such as the pancreatic β-cells, but not in non-secretory cell types. We have recently developed a mathematical model of UPR, focusing on the interplay and synergy between the TA arm and the conserved Ire1 arm of the UPR. The model showed that the TA mechanism is beneficial in highly fluctuating environment, for example, in the case where the ER stress changes frequently. Under highly variable levels of ER stress, tight regulation of the ER load by TA avoids excess amount of chaperons and proteases being produced. The model also showed that TA is of greater importance when there is a large flux of proteins through the ER. In this study, we further expand our model to investigate different types of ER stress and different temporal profiles of the stress. We found that TA is more desirable in dealing with the translation stress, for example, prolonged stimulation of proinsulin biosynthesis, than the chemical stress.

  20. Ranging Behaviour of Commercial Free-Range Laying Hens.

    Science.gov (United States)

    Chielo, Leonard Ikenna; Pike, Tom; Cooper, Jonathan

    2016-04-26

    In this study, the range use and behaviour of laying hens in commercial free-range flocks was explored. Six flocks were each visited on four separate days and data collected from their outdoor area (divided into zones based on distance from shed and available resources). These were: apron (0-10 m from shed normally without cover or other enrichments); enriched belt (10-50 m from shed where resources such as manmade cover, saplings and dust baths were provided); and outer range (beyond 50 m from shed with no cover and mainly grass pasture). Data collection consisted of counting the number of hens in each zone and recording behaviour, feather condition and nearest neighbour distance (NND) of 20 birds per zone on each visit day. In addition, we used techniques derived from ecological surveys to establish four transects perpendicular to the shed, running through the apron, enriched belt and outer range. Number of hens in each 10 m × 10 m quadrat was recorded four times per day as was the temperature and relative humidity of the outer range. On average, 12.5% of hens were found outside. Of these, 5.4% were found in the apron; 4.3% in the enriched zone; and 2.8% were in the outer range. This pattern was supported by data from quadrats, where the density of hens sharply dropped with increasing distance from shed. Consequently, NND was greatest in the outer range, least in the apron and intermediate in the enriched belt. Hens sampled in outer range and enriched belts had better feather condition than those from the apron. Standing, ground pecking, walking and foraging were the most commonly recorded activities with standing and pecking most likely to occur in the apron, and walking and foraging more common in the outer range. Use of the outer range declined with lower temperatures and increasing relative humidity, though use of apron and enriched belt was not affected by variation in these measures. These data support previous findings that outer range areas tend to be

  1. A resource for benchmarking the usefulness of protein structure models.

    KAUST Repository

    Carbajo, Daniel

    2012-08-02

    BACKGROUND: Increasingly, biologists and biochemists use computational tools to design experiments to probe the function of proteins and/or to engineer them for a variety of different purposes. The most effective strategies rely on the knowledge of the three-dimensional structure of the protein of interest. However it is often the case that an experimental structure is not available and that models of different quality are used instead. On the other hand, the relationship between the quality of a model and its appropriate use is not easy to derive in general, and so far it has been analyzed in detail only for specific application. RESULTS: This paper describes a database and related software tools that allow testing of a given structure based method on models of a protein representing different levels of accuracy. The comparison of the results of a computational experiment on the experimental structure and on a set of its decoy models will allow developers and users to assess which is the specific threshold of accuracy required to perform the task effectively. CONCLUSIONS: The ModelDB server automatically builds decoy models of different accuracy for a given protein of known structure and provides a set of useful tools for their analysis. Pre-computed data for a non-redundant set of deposited protein structures are available for analysis and download in the ModelDB database. IMPLEMENTATION, AVAILABILITY AND REQUIREMENTS: Project name: A resource for benchmarking the usefulness of protein structure models. Project home page: http://bl210.caspur.it/MODEL-DB/MODEL-DB_web/MODindex.php.Operating system(s): Platform independent. Programming language: Perl-BioPerl (program); mySQL, Perl DBI and DBD modules (database); php, JavaScript, Jmol scripting (web server). Other requirements: Java Runtime Environment v1.4 or later, Perl, BioPerl, CPAN modules, HHsearch, Modeller, LGA, NCBI Blast package, DSSP, Speedfill (Surfnet) and PSAIA. License: Free. Any restrictions to use by

  2. Homology Modeling: Generating Structural Models to Understand Protein Function and Mechanism

    Science.gov (United States)

    Ramachandran, Srinivas; Dokholyan, Nikolay V.

    Geneticists and molecular and cell biologists routinely uncover new proteins important in specific biological processes/pathways. However, either the molecular functions or the functional mechanisms of many of these proteins are unclear due to a lack of knowledge of their atomic structures. Yet, determining experimental structures of many proteins presents technical challenges. The current methods for obtaining atomic-resolution structures of biomolecules (X-ray crystallography and NMR spectroscopy) require pure preparations of proteins at concentrations much higher than those at which the proteins exist in a physiological environment. Additionally, NMR has size limitations, with current technology limited to the determination of structures of proteins with masses of up to 15 kDa. Due to these reasons, atomic structures of many medically and biologically important proteins do not exist. However, the structures of these proteins are essential for several purposes, including in silico drug design [1], understanding the effects of disease mutations [2], and designing experiments to probe the functional mechanisms of proteins. Comparative modeling has gained importance as a tool for bridging the gap between sequence and structure space, allowing researchers to build structural models of proteins that are difficult to crystallize or for which structure determination by NMR spectroscopy is not tractable. Comparative modeling, or homology modeling, exploits the fact that two proteins whose sequences are evolutionarily connected display similar structural features [3]. Thus, the known structure of a protein (template) can be used to generate a molecular model of the protein (query) whose experimental structure is notknown.

  3. Protein buffering in model systems and in whole human saliva.

    Directory of Open Access Journals (Sweden)

    Andreas Lamanda

    Full Text Available The aim of this study was to quantify the buffer attributes (value, power, range and optimum of two model systems for whole human resting saliva, the purified proteins from whole human resting saliva and single proteins. Two model systems, the first containing amyloglucosidase and lysozyme, and the second containing amyloglucosidase and alpha-amylase, were shown to provide, in combination with hydrogencarbonate and di-hydrogenphosphate, almost identical buffer attributes as whole human resting saliva. It was further demonstrated that changes in the protein concentration as small as 0.1% may change the buffer value of a buffer solution up to 15 times. Additionally, it was shown that there was a protein concentration change in the same range (0.16% between saliva samples collected at the time periods of 13:00 and others collected at 9:00 am and 17:00. The mode of the protein expression changed between these samples corresponded to the change in basic buffer power and the change of the buffer value at pH 6.7. Finally, SDS Page and Ruthenium II tris (bathophenantroline disulfonate staining unveiled a constant protein expression in all samples except for one 50 kDa protein band. As the change in the expression pattern of that 50 kDa protein band corresponded to the change in basic buffer power and the buffer value at pH 6.7, it was reasonable to conclude that this 50 kDa protein band may contain the protein(s belonging to the protein buffer system of human saliva.

  4. Effect of γ-Aminobutyric Acid-producing Strain on Laying Performance, Egg Quality and Serum Enzyme Activity in Hy-Line Brown Hens under Heat Stress

    Directory of Open Access Journals (Sweden)

    Y. Z. Zhu

    2015-07-01

    Full Text Available Heat-stress remains a costly issue for animal production, especially for poultry as they lack sweat glands, and alleviating heat-stress is necessary for ensuring animal production in hot environment. A high γ-aminobutyric acid (GABA-producer Lactobacillus strain was used to investigate the effect of dietary GABA-producer on laying performance and egg quality in heat-stressed Hy-line brown hens. Hy-Line brown hens (n = 1,164 at 280 days of age were randomly divided into 4 groups based on the amount of freeze-dried GABA-producer added to the basal diet as follows: i 0 mg/kg, ii 25 mg/kg, iii 50 mg/kg, and iv 100 mg/kg. All hens were subjected to heat-stress treatment through maintaining the temperature and the relative humidity at 28.83±3.85°C and 37% to 53.9%, respectively. During the experiment, laying rate, egg weight and feed intake of hens were recorded daily. At the 30th and 60th day after the start of the experiment, biochemical parameters, enzyme activity and immune activity in serum were measured. Egg production, average egg weight, average daily feed intake, feed conversion ratio and percentage of speckled egg, soft shell egg and misshaped egg were significantly improved (p<0.05 by the increasing supplementation of the dietary GABA-producer. Shape index, eggshell thickness, strength and weight were increased linearly with increasing GABA-producer supplementation. The level of calcium, phosphorus, glucose, total protein and albumin in serum of the hens fed GABA-producing strain supplemented diet was significantly higher (p<0.05 than that of the hens fed the basal diet, whereas cholesterol level was decreased. Compared with the basal diet, GABA-producer strain supplementation increased serum level of glutathione peroxidase (p = 0.009 and superoxide dismutase. In conclusion, GABA-producer played an important role in alleviating heat-stress, the isolated GABA-producer strain might be a potential natural and safe probiotic to use to

  5. Molecular modeling of protein materials: case study of elastin

    Science.gov (United States)

    Tarakanova, Anna; Buehler, Markus J.

    2013-09-01

    Molecular modeling of protein materials is a quickly growing area of research that has produced numerous contributions in fields ranging from structural engineering to medicine and biology. We review here the history and methods commonly employed in molecular modeling of protein materials, emphasizing the advantages for using modeling as a complement to experimental work. We then consider a case study of the protein elastin, a critically important ‘mechanical protein’ to exemplify the approach in an area where molecular modeling has made a significant impact. We outline the progression of computational modeling studies that have considerably enhanced our understanding of this important protein which endows elasticity and recoil to the tissues it is found in, including the skin, lungs, arteries and the heart. A vast collection of literature has been directed at studying the structure and function of this protein for over half a century, the first molecular dynamics study of elastin being reported in the 1980s. We review the pivotal computational works that have considerably enhanced our fundamental understanding of elastin's atomistic structure and its extraordinary qualities—focusing on two in particular: elastin's superb elasticity and the inverse temperature transition—the remarkable ability of elastin to take on a more structured conformation at higher temperatures, suggesting its effectiveness as a biomolecular switch. Our hope is to showcase these methods as both complementary and enriching to experimental approaches that have thus far dominated the study of most protein-based materials.

  6. Adaptive Simulated Annealing Based Protein Loop Modeling of Neurotoxins

    Institute of Scientific and Technical Information of China (English)

    陈杰; 黄丽娜; 彭志红

    2003-01-01

    A loop modeling method, adaptive simulated annealing, for ab initio prediction of protein loop structures, as an optimization problem of searching the global minimum of a given energy function, is proposed. An interface-friendly toolbox-LoopModeller in Windows and Linux systems, VC++ and OpenGL environments is developed for analysis and visualization. Simulation results of three short-chain neurotoxins modeled by LoopModeller show that the method proposed is fast and efficient.

  7. Perching behaviour and perch height preference of laying hens in furnished cages varying in height.

    Science.gov (United States)

    Struelens, E; Tuyttens, F A M; Duchateau, L; Leroy, T; Cox, M; Vranken, E; Buyse, J; Zoons, J; Berckmans, D; Odberg, F; Sonck, B

    2008-07-01

    1. The objective was to investigate the effect of cage height on perch height preference and perching behaviour in laying hens. Twelve groups of two hens and 12 groups of 14 hens were tested in furnished cages equipped with two wooden perches. These stepwise perches were designed such that hens could choose between 7 different heights (6, 11, 16, 21, 26, 31 and 36 cm). Day- and night-time perching behaviour was observed on 4 consecutive days with a different cage height each day: 150, 55, 50 and 45 cm. 2. Given that a minimum perch-roof distance of 19 to 24 cm was available, hens preferred to roost on the highest perches at night. 3. Lowering cage height not only forced hens to use lower perches, but also reduced time spent on the perches during the day (two-hen and 14-hen test) and night (14-hen test). Moreover, it affected daytime behavioural activities (more standing and less preening) on the perches in the two-hen tests (but not in the 14-hen tests). 4. During the day lower perches were used more for standing and walking, higher perches more for sitting and sleeping. This behavioural differentiation was most pronounced in the highest cages. 5. Perch preference and perching behaviour depend on both the floor-perch distance and the perch-roof distance. Higher cages provide more opportunity for higher perches (which hens prefer), for better three-dimensional spacing (and consequently reduced density at floor level) and for behavioural differentiation according to perch height.

  8. PERFORMANCE AND EGGS QUALITY OF HENS OF GENETIC RESOURCES OF THE CZECH REPUBLIC AND SLOVAKIA

    Directory of Open Access Journals (Sweden)

    Zdeněk Ledvinka

    2015-03-01

    Full Text Available The aim of this study was to assess the performance and technological values of eggs of Czech Hen and Oravka breeds housed on litter. The assumption was that the genotype of hens affects their performance, egg weight, and parameters of yolk, albumen and eggshell quality. A total of 30 pullets of Czech Hen breed and 30 pullets of Oravka breed in the age of 17 weeks were included in to the experiment. Environmental conditions corresponded to the standard requirements for laying hens in observed type of housing system. Hen day egg production, egg yield, daily feed consumption per hen, feed consumption per egg and egg weight, egg shape index, proportion and index of yolk and albumen,yolk colour and Haugh units score were monitored in the experiment. From the parameters of eggshell, proportion, thickness, strength and colour of eggshell were observed. Performance parameters of laying hens weren't affected by the genotype of hens. Czech Hen breed showed insignificantly the higher value in all indicators. The significantly (P≤0.01 and P≤0.001 better values of eggshell quality parameters were detected in Czech Hen breed. We found out that Czech Hen breed had also statistically significantly lighter colour of eggshell. There were no significant interbreed differences in egg weight, proportion of yolk and albumen. The egg shape index was significantly higher in Oravka. Index of yolk and albumen was also significantly (P≤0.001 higher in Oravka. Haugh units score, that reflect the quality of the eggs, were found significantly (P≤0.001higher in Oravka too. On the other hand, yolk colour was detected significantly (P≤0.001 darker for the Czech Hen.

  9. A CONTINUUM HARD-SPHERE MODEL OF PROTEIN ADSORPTION.

    Science.gov (United States)

    Finch, Craig; Clarke, Thomas; Hickman, James J

    2013-07-01

    Protein adsorption plays a significant role in biological phenomena such as cell-surface interactions and the coagulation of blood. Two-dimensional random sequential adsorption (RSA) models are widely used to model the adsorption of proteins on solid surfaces. Continuum equations have been developed so that the results of RSA simulations can be used to predict the kinetics of adsorption. Recently, Brownian dynamics simulations have become popular for modeling protein adsorption. In this work a continuum model was developed to allow the results from a Brownian dynamics simulation to be used as the boundary condition in a computational fluid dynamics (CFD) simulation. Brownian dynamics simulations were used to model the diffusive transport of hard-sphere particles in a liquid and the adsorption of the particles onto a solid surface. The configuration of the adsorbed particles was analyzed to quantify the chemical potential near the surface, which was found to be a function of the distance from the surface and the fractional surface coverage. The near-surface chemical potential was used to derive a continuum model of adsorption that incorporates the results from the Brownian dynamics simulations. The equations of the continuum model were discretized and coupled to a CFD simulation of diffusive transport to the surface. The kinetics of adsorption predicted by the continuum model closely matched the results from the Brownian dynamics simulation. This new model allows the results from mesoscale simulations to be incorporated into micro- or macro-scale CFD transport simulations of protein adsorption in practical devices.

  10. Protein Structure Classification and Loop Modeling Using Multiple Ramachandran Distributions

    KAUST Repository

    Najibi, Seyed Morteza

    2017-02-08

    Recently, the study of protein structures using angular representations has attracted much attention among structural biologists. The main challenge is how to efficiently model the continuous conformational space of the protein structures based on the differences and similarities between different Ramachandran plots. Despite the presence of statistical methods for modeling angular data of proteins, there is still a substantial need for more sophisticated and faster statistical tools to model the large-scale circular datasets. To address this need, we have developed a nonparametric method for collective estimation of multiple bivariate density functions for a collection of populations of protein backbone angles. The proposed method takes into account the circular nature of the angular data using trigonometric spline which is more efficient compared to existing methods. This collective density estimation approach is widely applicable when there is a need to estimate multiple density functions from different populations with common features. Moreover, the coefficients of adaptive basis expansion for the fitted densities provide a low-dimensional representation that is useful for visualization, clustering, and classification of the densities. The proposed method provides a novel and unique perspective to two important and challenging problems in protein structure research: structure-based protein classification and angular-sampling-based protein loop structure prediction.

  11. Random field model reveals structure of the protein recombinational landscape.

    Directory of Open Access Journals (Sweden)

    Philip A Romero

    Full Text Available We are interested in how intragenic recombination contributes to the evolution of proteins and how this mechanism complements and enhances the diversity generated by random mutation. Experiments have revealed that proteins are highly tolerant to recombination with homologous sequences (mutation by recombination is conservative; more surprisingly, they have also shown that homologous sequence fragments make largely additive contributions to biophysical properties such as stability. Here, we develop a random field model to describe the statistical features of the subset of protein space accessible by recombination, which we refer to as the recombinational landscape. This model shows quantitative agreement with experimental results compiled from eight libraries of proteins that were generated by recombining gene fragments from homologous proteins. The model reveals a recombinational landscape that is highly enriched in functional sequences, with properties dominated by a large-scale additive structure. It also quantifies the relative contributions of parent sequence identity, crossover locations, and protein fold to the tolerance of proteins to recombination. Intragenic recombination explores a unique subset of sequence space that promotes rapid molecular diversification and functional adaptation.

  12. WATGEN: an algorithm for modeling water networks at protein-protein interfaces.

    Science.gov (United States)

    Bui, Huynh-Hoa; Schiewe, Alexandra J; Haworth, Ian S

    2007-11-15

    Water molecules at protein-protein interfaces contribute to the close packing of atoms and ensure complementarity between the protein surfaces, as well as mediating polar interactions. Therefore, modeling of interface water is of importance in understanding the structural basis of biomolecular association. We present an algorithm, WATGEN, which predicts locations for water molecules at a protein-protein or protein-peptide interface, given the atomic coordinates of the protein and peptide. A key element of the WATGEN algorithm is the prediction of water sites that can form multiple hydrogen bonds that bridge the binding interface. Trial calculations were performed on water networks predicted by WATGEN at 126 protein-peptide interfaces (X-ray resolutions algorithm predicts 72 and 88% of these sites within 1.5 and 2.0 A, respectively. The predicted number of water molecules at each interface was much higher than the number of water molecules identified experimentally. Therefore, random placement of the same number of water molecules as that predicted at each interface was performed as a control, and resulted in only 22 and 40% of water sites placed within 1.5 and 2.0 A of experimental sites, respectively. Based on these data, we conclude that WATGEN can accurately predict the location of water molecules at a protein-peptide interface, and this may be of value for understanding the energetics and specificity of biomolecular association. (c) 2007 Wiley Periodicals, Inc.

  13. A computational model of the LGI1 protein suggests a common binding site for ADAM proteins.

    Directory of Open Access Journals (Sweden)

    Emanuela Leonardi

    Full Text Available Mutations of human leucine-rich glioma inactivated (LGI1 gene encoding the epitempin protein cause autosomal dominant temporal lateral epilepsy (ADTLE, a rare familial partial epileptic syndrome. The LGI1 gene seems to have a role on the transmission of neuronal messages but the exact molecular mechanism remains unclear. In contrast to other genes involved in epileptic disorders, epitempin shows no homology with known ion channel genes but contains two domains, composed of repeated structural units, known to mediate protein-protein interactions.A three dimensional in silico model of the two epitempin domains was built to predict the structure-function relationship and propose a functional model integrating previous experimental findings. Conserved and electrostatic charged regions of the model surface suggest a possible arrangement between the two domains and identifies a possible ADAM protein binding site in the β-propeller domain and another protein binding site in the leucine-rich repeat domain. The functional model indicates that epitempin could mediate the interaction between proteins localized to different synaptic sides in a static way, by forming a dimer, or in a dynamic way, by binding proteins at different times.The model was also used to predict effects of known disease-causing missense mutations. Most of the variants are predicted to alter protein folding while several other map to functional surface regions. In agreement with experimental evidence, this suggests that non-secreted LGI1 mutants could be retained within the cell by quality control mechanisms or by altering interactions required for the secretion process.

  14. Eggshell quality, eggshell structure and small intestinal histology in laying hens fed dietary Pantoea-6® and plant extracts

    OpenAIRE

    Kanda Lokaewmanee; Koh-en Yamauchi; Tsutomu Komori; Keiko Saito

    2014-01-01

    The present study aims to investigate the effects of dietary Pantoea-6® (extract of fermented wheat flour with Pantoea agglomerans) and plant extracts (red clover and garlic) on eggshell quality and structure and intestinal histology. Sixty-six Boris Brown laying hens (30 weeks old) were allotted to 3 groups, each with eleven replicates of two chickens. The control group was fed a basal diet (18% crude protein, 2850 kcal/kg ME) and the other groups were fed the basal diet supplemented with 0....

  15. Markov dynamic models for long-timescale protein motion.

    KAUST Repository

    Chiang, Tsung-Han

    2010-06-01

    Molecular dynamics (MD) simulation is a well-established method for studying protein motion at the atomic scale. However, it is computationally intensive and generates massive amounts of data. One way of addressing the dual challenges of computation efficiency and data analysis is to construct simplified models of long-timescale protein motion from MD simulation data. In this direction, we propose to use Markov models with hidden states, in which the Markovian states represent potentially overlapping probabilistic distributions over protein conformations. We also propose a principled criterion for evaluating the quality of a model by its ability to predict long-timescale protein motions. Our method was tested on 2D synthetic energy landscapes and two extensively studied peptides, alanine dipeptide and the villin headpiece subdomain (HP-35 NleNle). One interesting finding is that although a widely accepted model of alanine dipeptide contains six states, a simpler model with only three states is equally good for predicting long-timescale motions. We also used the constructed Markov models to estimate important kinetic and dynamic quantities for protein folding, in particular, mean first-passage time. The results are consistent with available experimental measurements.

  16. Control methods for Dermanyssus gallinae in systems for laying hens

    DEFF Research Database (Denmark)

    Mul, M.; Fiks-van Niekerk, T.; Chirico, J.

    2009-01-01

    This paper reports the results of a seminar on poultry red mite (PRM), Dermanyssus gallinae. Eighteen researchers from eight European countries discussed life cycle issues of the mite, effects of mites on hens and egg production, and monitoring and control methods for PRM in poultry facilities...... and admitting the problem and in taking timely measures. Currently, the most promising control method combines heating the hen house in combination with chemical treatments. Future areas of development which show promise include the use of entomopathogenic fungi, vaccination and predatory mites. The final aim....... It was determined that PRM probably causes more damage than envisaged, with the cost in The Netherlands alone reaching 11 million euro per annum. However a great deal is still unknown about PRM (e.g. reproduction, survival methods, etc.) and that PRM monitoring is an important instrument in recognising...

  17. Plasma corticosterone levels in laying hens from three different housing systems: preliminary results

    Directory of Open Access Journals (Sweden)

    Giampaolo Asdrubali

    2010-01-01

    Full Text Available Adrenocortical and thyroidal hormones are physiological indicators of various forms of stress in the fowl. In order to establish possible variations in corticosterone levels, blood samples were collected from ISA Brown hens reared in three different housing systems (cage, floor and organic way. Results showed that corticosterone concentrations were highest in caged hens, intermediate in organic reared hens and lowest in floor reared hens. It could be assumed that in the last one system birds have an adequate space in controlled environment that permits them to satisfy, though partially, their behavioural needs without the presence of different chronic stress factors acting in the other systems.

  18. Reduction of Protein Networks Models by Passivity Preserving Projection

    Institute of Scientific and Technical Information of China (English)

    Luca Mesin; Flavio Canavero; Lamberto Rondoni

    2013-01-01

    Reduction of complex protein networks models is of great importance.The accuracy of a passivity preserving algorithm (PRIMA) for model order reduction (MOR) is here tested on protein networks,introducing innovative variations of the standard PRIMA method to fit the problem at hand.The reduction method does not require to solve the complete system,resulting in a promising tool for studying very large-scale models for which the full solution cannot be computed.The mathematical structure of the considered kinetic equations is preserved.Keeping constant the reduction factor,the approximation error is lower for larger systems.

  19. Housing and dustbathing effects on northern fowl mites (Ornithonyssus sylviarum) and chicken body lice (Menacanthus stramineus) on hens.

    Science.gov (United States)

    Martin, C D; Mullens, B A

    2012-09-01

    Hen housing (cage or cage-free) did not impact overall abundances of northern fowl mites, Ornithonyssus sylviarum (Canestrini & Fanzago) (Acari: Macronyssidae), or chicken body lice, Menacanthus stramineus (Nitzsch) (Phthiraptera: Menoponidae). Cage-free hens received a dustbox with sand plus diatomaceous earth (DE), kaolin clay or sulphur. Weekly use varied from none to 100% of hens; 73% of hens used the dustbox at least once. Ectoparasite populations on dustbathing hens (users) were compared with those on non-user cage-free and caged hens. All materials reduced ectoparasites on user hens by 80-100% after 1 week of dustbox use. Diatomaceous earth and kaolin failed to reduce ectoparasites on non-user hens, and ectoparasites on user hens recovered after dustbox removal. A sulphur dustbox eliminated mites from all hens (including non-users) within 2-4 weeks. Residual sulphur controlled mites until the end of the experiment (up to 9 weeks), even after the dustbox was removed. Louse populations on hens using the sulphur dustbox were reduced in 1-2 weeks. Residual sulphur effects were less evident in lice, but the use of a sulphur dustbox by a higher proportion of hens extended louse control to all hens. This is the first experimental study to show that bird dustbathing in naturally and widely available dust materials (particularly kaolin) can suppress ectoparasites and thus the behaviour is probably adaptive. © 2012 The Authors. Medical and Veterinary Entomology © 2012 The Royal Entomological Society.

  20. Dissipative electro-elastic network model of protein electrostatics

    CERN Document Server

    Martin, Daniel R; Matyushov, Dmitry V

    2011-01-01

    We propose a dissipative electro-elastic network model (DENM) to describe the dynamics and statistics of electrostatic fluctuations at active sites of proteins. The model combines the harmonic network of residue beads with overdamped dynamics of the normal modes of the network characterized by two friction coefficients. The electrostatic component is introduced to the model through atomic charges of the protein force field. The overall effect of the electrostatic fluctuations of the network is recorded through the frequency-dependent response functions of the electrostatic potential and electric field at the active site. We also consider the dynamics of displacements of individual residues in the network and the dynamics of distances between pairs of residues. The model is tested against loss spectra of residue displacements and the electrostatic potential and electric field at the heme's iron from all-atom molecular dynamics simulations of three hydrated globular proteins.

  1. Fiber level for laying hens during the growing phase

    Directory of Open Access Journals (Sweden)

    Ednardo Rodrigues Freitas

    2014-04-01

    Full Text Available Feeding management of laying hens has been focused on the direct influence of nutrient intake on weight gain, especially at growing phase. This study evaluates nutrient digestibility, performance, development of the digestive tract, body composition, and bone quality of two strains of laying hens fed with different levels of neutral detergent fiber (NDF during the growing phase from the 7th to the 12th week of age. A total of 1,296 birds were distributed in a completely randomized design in a 2 x 3 factorial arrangement (two strains x three levels of NDF with four replicates of 54 birds per treatment. Semi-heavy (Hy Line Brown and light-strain (Lohman LSL pullets were allotted to dietary treatments consisting of 14.50, 16.50, and 18.50% NDF. An interaction between strains and NDF levels was observed only for feed/gain ratio and light-strain pullets had lower performance with 18.50% NDF. The increasing levels of NDF in the diet reduced the coefficients of digestibility of dry matter, nitrogen and gross energy, and the values of metabolizable energy. Higher levels of NDF in the diet increased the relative weight of liver and intestines and reduced gizzard weight. It was also observed differences between bone quality and composition of the femur and tibia of light and semi-heavy hens. The increase in NDF level in ration for growing phase laying hens above 14.50% decreases the nutrient digestibility and the metabolizable energy of the diet; however, it does not affect the carcass composition, bone quality, feed intake, and weight gain, although it may impair feed conversion of light-strain pullets.

  2. Determination of residues of sulphonamide in eggs and laying hens.

    Science.gov (United States)

    Tabassum, Shazia; Ahmad, H B; Nawaz, R

    2007-07-01

    Eggs were collected from different areas of Faisalabad city. The quantity of sulphonamides was determined in yolk, white and whole egg and compared with the permissible limit 1 microg/ml for sulphadimethoxine available in literature. In another experiment, a group of hens were kept at a poultry farm after medicating them with darvisal liquid to see if the residues of sulphonamide pass into the eggs of poultry. The period of existence of residues was noted.

  3. Investigating social discrimination of group members by laying hens.

    Science.gov (United States)

    Abeyesinghe, Siobhan M; McLeman, Morven A; Owen, Rachael C; McMahon, Claire E; Wathes, Christopher M

    2009-05-01

    Social relationships in domestic fowl are commonly assumed to rely on social recognition and its pre-requisite, discrimination of group-mates. If this is true, then the unnatural physical and social environments in which commercial laying hens are typically housed, when compared with those in which their progenitor species evolved, may compromise social function with consequent implications for welfare. Our aims were to determine whether adult hens can discriminate between unique pairs of familiar conspecifics, and to establish the most appropriate method for assessing this social discrimination. We investigated group-mate discrimination using two learning tasks in which there was bi-directional exchange of visual, auditory and olfactory information. Learning occurred in a Y-maze task (psocial discrimination or to the response task. Learning also failed to occur in this familiar/unfamiliar social discrimination task (p=0.001; n=1/10). Our findings demonstrate unequivocally that adult laying hens kept in small groups, under environmental conditions more consistent with those in which sensory capacities evolved, can discriminate group members: however, appropriate methods to demonstrate discrimination are crucial.

  4. The atypical emission-line star Hen3-209

    Science.gov (United States)

    Nazé, Y.; Rauw, G.; Hutsemékers, D.; Gosset, E.; Manfroid, J.; Royer, P.

    2006-10-01

    We analyse observations, spanning 15 yr, dedicated to the extreme emission-line object Hen3-209. Our photometric data indicate that the luminosity of the star undergoes marked variations with a peak-to-peak amplitude of 0.65 mag. These variations are recurrent, with a period of 16.093 +/-0.005 d. The spectrum of Hen3-209 is peculiar with many different lines (HI, HeI, FeII, ...) showing P Cygni profiles. The line profiles are apparently changing in harmony with the photometry. The spectrum also contains [OIII] lines that display a saddle profile topped by three peaks, with a maximum separation of about 600 kms-1. Hen3-209 is most likely an evolved luminous object suffering from mass ejection events and maybe belonging to a binary system. Based on observations collected at the European Southern Observatory (La Silla, Chile) and the Cerro-Tololo Observatory (Chile). Postdoctoral Researcher FNRS (Belgium). ‡ E-mail: naze@astro.ulg.ac.be § Research Associate FNRS (Belgium). ¶ Research Director FNRS (Belgium).

  5. Utilization of sunflower seed in laying hen rations

    Directory of Open Access Journals (Sweden)

    Tsuzuki ET

    2003-01-01

    Full Text Available The objective of this trial was to evaluate the effect of sunflower seed inclusion (0, 1.4, 2.8, 4.2 and 5.6% in a laying hen diet containing corn, soybean meal, wheat meal and soybean oil as main ingredients on performance and egg quality. The evaluated variables were daily feed intake, average egg weight, feed conversion (kg.kg-1 and kg.dz-1, eggshell percentage, yolk color and Haugh unit. One hundred and sixty 25 week-old Lohmann laying hens were used in a completely randomized design with five treatments and four replications of eight birds per experimental unit. Four periods of 28 days were evaluated during 112 days. The inclusion of sunflower seed in the diet had no effect on production parameters during the experimental period. Thus, can be concluded that sunflower seed might be used at concentrations up to 5.6% in laying hen diets without affecting performance and egg quality.

  6. Model of a DNA-protein complex of the architectural monomeric protein MC1 from Euryarchaea.

    Directory of Open Access Journals (Sweden)

    Françoise Paquet

    Full Text Available In Archaea the two major modes of DNA packaging are wrapping by histone proteins or bending by architectural non-histone proteins. To supplement our knowledge about the binding mode of the different DNA-bending proteins observed across the three domains of life, we present here the first model of a complex in which the monomeric Methanogen Chromosomal protein 1 (MC1 from Euryarchaea binds to the concave side of a strongly bent DNA. In laboratory growth conditions MC1 is the most abundant architectural protein present in Methanosarcina thermophila CHTI55. Like most proteins that strongly bend DNA, MC1 is known to bind in the minor groove. Interaction areas for MC1 and DNA were mapped by Nuclear Magnetic Resonance (NMR data. The polarity of protein binding was determined using paramagnetic probes attached to the DNA. The first structural model of the DNA-MC1 complex we propose here was obtained by two complementary docking approaches and is in good agreement with the experimental data previously provided by electron microscopy and biochemistry. Residues essential to DNA-binding and -bending were highlighted and confirmed by site-directed mutagenesis. It was found that the Arg25 side-chain was essential to neutralize the negative charge of two phosphates that come very close in response to a dramatic curvature of the DNA.

  7. A simple probabilistic model of multibody interactions in proteins.

    Science.gov (United States)

    Johansson, Kristoffer Enøe; Hamelryck, Thomas

    2013-08-01

    Protein structure prediction methods typically use statistical potentials, which rely on statistics derived from a database of know protein structures. In the vast majority of cases, these potentials involve pairwise distances or contacts between amino acids or atoms. Although some potentials beyond pairwise interactions have been described, the formulation of a general multibody potential is seen as intractable due to the perceived limited amount of data. In this article, we show that it is possible to formulate a probabilistic model of higher order interactions in proteins, without arbitrarily limiting the number of contacts. The success of this approach is based on replacing a naive table-based approach with a simple hierarchical model involving suitable probability distributions and conditional independence assumptions. The model captures the joint probability distribution of an amino acid and its neighbors, local structure and solvent exposure. We show that this model can be used to approximate the conditional probability distribution of an amino acid sequence given a structure using a pseudo-likelihood approach. We verify the model by decoy recognition and site-specific amino acid predictions. Our coarse-grained model is compared to state-of-art methods that use full atomic detail. This article illustrates how the use of simple probabilistic models can lead to new opportunities in the treatment of nonlocal interactions in knowledge-based protein structure prediction and design. Copyright © 2013 Wiley Periodicals, Inc., a Wiley company.

  8. THE APPLICATION OF POLYNOMIAL REGRESSIONS IN THE PERFORMING EVALUATION OF LAYING HENS FED WITH FODDERS USING AMINO ACIDS SUPPLEMENTATION

    Directory of Open Access Journals (Sweden)

    ELIZA SIMIZ

    2013-12-01

    Full Text Available The experiment has been carried out in the Poultry Department from the Didactic Station of Banat`s University of Agricultural Sciences and Veterinary Medicine Timisoara, on 100 laying hens, 32-39 weeks old - the hybrid Shaver 579. We have distributed the hens in 4 groups, with fodder recipes including two protein levels (16.2% and respectively 15.2% and different amino acid contents. As regarding the egg production weight, we have remarked group 4 (1.25 kg; this group was fed a combined feed with 15.20% crude protein, 0.82% lysine and 0.42% methionine. Simple correlations analysis and third degree polynomial regressions have led to the conclusion that there is a strong positive correlation between the obtained egg weight and the lysine or methionine intake. The highest correlation coefficient characterizes the experimental group 3 (0.882, p=0.004. The regression curves recorded for group 4 prove that the egg mass increases in the same time with ingestion up to the level of 19.83 g protein, 1069 mg lysine and 547 mg methionine, and then it does not react anymore concomitantly with the increase of the lysine or methionine ingestion.

  9. Protein carbonylation, protein aggregation and neuronal cell death in a murine model of multiple sclerosis

    Science.gov (United States)

    Dasgupta, Anushka

    Many studies have suggested that oxidative stress plays an important role in the pathophysiology of both multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE). Yet, the mechanism by which oxidative stress leads to tissue damage in these disorders is unclear. Recent work from our laboratory has revealed that protein carbonylation, a major oxidative modification caused by severe and/or chronic oxidative stress conditions, is elevated in MS and EAE. Furthermore, protein carbonylation has been shown to alter protein structure leading to misfolding/aggregation. These findings prompted me to hypothesize that carbonylated proteins, formed as a consequence of oxidative stress and/or decreased proteasomal activity, promote protein aggregation to mediate neuronal apoptosis in vitro and in EAE. To test this novel hypothesis, I first characterized protein carbonylation, protein aggregation and apoptosis along the spinal cord during the course of myelin-oligodendrocyte glycoprotein (MOG)35-55 peptide-induced EAE in C57BL/6 mice [Chapter 2]. The results show that carbonylated proteins accumulate throughout the course of the disease, albeit by different mechanisms: increased oxidative stress in acute EAE and decreased proteasomal activity in chronic EAE. I discovered not only that there is a temporal correlation between protein carbonylation and apoptosis but also that carbonyl levels are significantly higher in apoptotic cells. A high number of juxta-nuclear and cytoplasmic protein aggregates containing the majority of the oxidized proteins are also present during the course of EAE, which seems to be due to reduced autophagy. In chapter 3, I show that when gluthathione levels are reduced to those in EAE spinal cord, both neuron-like PC12 (nPC12) cells and primary neuronal cultures accumulate carbonylated proteins and undergo cell death (both by necrosis and apoptosis). Immunocytochemical and biochemical studies also revealed a temporal

  10. Coarse-grained models of protein folding: toy models or predictive tools?

    Science.gov (United States)

    Clementi, Cecilia

    2008-02-01

    Coarse-grained models are emerging as a practical alternative to all-atom simulations for the characterization of protein folding mechanisms over long time scales. While a decade ago minimalist toy models were mainly designed to test general hypotheses on the principles regulating protein folding, the latest coarse-grained models are increasingly realistic and can be used to characterize quantitatively the detailed folding mechanism of specific proteins. The ability of such models to reproduce the essential features of folding dynamics suggests that each single atomic degree of freedom is not by itself particularly relevant to folding and supports a statistical mechanical approach to characterize folding transitions. When combined with more refined models and with experimental studies, the systematic investigation of protein systems and complexes using coarse-grained models can advance our theoretical understanding of the actual organizing principles that emerge from the complex network of interactions among protein atomic constituents.

  11. Ab initio modeling of small proteins by iterative TASSER simulations

    Directory of Open Access Journals (Sweden)

    Zhang Yang

    2007-05-01

    Full Text Available Abstract Background Predicting 3-dimensional protein structures from amino-acid sequences is an important unsolved problem in computational structural biology. The problem becomes relatively easier if close homologous proteins have been solved, as high-resolution models can be built by aligning target sequences to the solved homologous structures. However, for sequences without similar folds in the Protein Data Bank (PDB library, the models have to be predicted from scratch. Progress in the ab initio structure modeling is slow. The aim of this study was to extend the TASSER (threading/assembly/refinement method for the ab initio modeling and examine systemically its ability to fold small single-domain proteins. Results We developed I-TASSER by iteratively implementing the TASSER method, which is used in the folding test of three benchmarks of small proteins. First, data on 16 small proteins (α-root mean square deviation (RMSD of 3.8Å, with 6 of them having a Cα-RMSD α-RMSD α-RMSD of the I-TASSER models was 3.9Å, whereas it was 5.9Å using TOUCHSTONE-II software. Finally, 20 non-homologous small proteins (α-RMSD of 3.9Å was obtained for the third benchmark, with seven cases having a Cα-RMSD Conclusion Our simulation results show that I-TASSER can consistently predict the correct folds and sometimes high-resolution models for small single-domain proteins. Compared with other ab initio modeling methods such as ROSETTA and TOUCHSTONE II, the average performance of I-TASSER is either much better or is similar within a lower computational time. These data, together with the significant performance of automated I-TASSER server (the Zhang-Server in the 'free modeling' section of the recent Critical Assessment of Structure Prediction (CASP7 experiment, demonstrate new progresses in automated ab initio model generation. The I-TASSER server is freely available for academic users http://zhang.bioinformatics.ku.edu/I-TASSER.

  12. Study of Salmonella Typhimurium Infection in Laying Hens.

    Science.gov (United States)

    Pande, Vivek V; Devon, Rebecca L; Sharma, Pardeep; McWhorter, Andrea R; Chousalkar, Kapil K

    2016-01-01

    Members of Salmonella enterica are frequently involved in egg and egg product related human food poisoning outbreaks worldwide. In Australia, Salmonella Typhimurium is frequently involved in egg and egg product related foodborne illness and Salmonella Mbandaka has also been found to be a contaminant of the layer farm environment. The ability possessed by Salmonella Enteritidis to colonize reproductive organs and contaminate developing eggs has been well-described. However, there are few studies investigating this ability for Salmonella Typhimurium. The hypothesis of this study was that the Salmonella Typhimurium can colonize the gut for a prolonged period of time and that horizontal infection through feces is the main route of egg contamination. At 14 weeks of age hens were orally infected with either S. Typhimurium PT 9 or S. Typhimurium PT 9 and Salmonella Mbandaka. Salmonella shedding in feces and eggs was monitored for 15 weeks post-infection. Egg shell surface and internal contents of eggs laid by infected hens were cultured independently for detection of Salmonella spp. The mean Salmonella load in feces ranged from 1.54 to 63.35 and 0.31 to 98.38 most probable number/g (MPN/g) in the S. Typhimurium and S. Typhimurium + S. Mbandaka group, respectively. No correlation was found between mean fecal Salmonella load and frequency of egg shell contamination. Egg shell contamination was higher in S. Typhimurium + S. Mbandaka infected group (7.2% S. Typhimurium, 14.1% S. Mbandaka) compared to birds infected with S. Typhimurium (5.66%) however, co-infection had no significant impact on egg contamination by S. Typhimurium. Throughout the study Salmonella was not recovered from internal contents of eggs laid by hens. Salmonella was isolated from different segments of oviduct of hens from both the groups, however pathology was not observed on microscopic examination. This study investigated Salmonella shedding for up to 15 weeks p.i which is a longer period of time

  13. Do laying hens with keel bone fractures experience pain?

    Science.gov (United States)

    Nasr, Mohammed A F; Nicol, Christine J; Murrell, Joanna C

    2012-01-01

    The European ban on battery cages has forced a change towards the use of non-cage or furnished cage systems, but unexpectedly this has been associated with an increased prevalence of keel bone fractures in laying hens. Bone fractures are acutely painful in mammals, but the effect of fractures on bird welfare is unclear. We recently reported that keel bone fractures have an effect on bird mobility. One possible explanation for this is that flying becomes mechanically impaired. However it is also possible that if birds have a capacity to feel pain, then ongoing pain resulting from the fracture could contribute to decreased mobility. The aim was to provide proof of concept that administration of appropriate analgesic drugs improves mobility in birds with keel fracture; thereby contributing to the debate about the capacity of birds to experience pain and whether fractures are associated with pain in laying hens. In hens with keel fractures, butorphanol decreased the latency to land from perches compared with latencies recorded for these hens following saline (mean (SEM) landing time (seconds) birds with keel fractures treated with butorphanol and saline from the 50, 100 and 150 cm perch heights respectively 1.7 (0.3), 2.2 (0.3), p = 0.05, 50 cm; 12.5 (6.6), 16.9 (6.7), p = 0.03, 100 cm; 20.6 (7.4), 26.3 (7.6), p = 0.02 150 cm). Mobility indices were largely unchanged in birds without keel fractures following butorphanol. Critically, butorphanol can be considered analgesic in our study because it improved the ability of birds to perform a complex behaviour that requires both motivation and higher cognitive processing. This is the first study to provide a solid evidential base that birds with keel fractures experience pain, a finding that has significant implications for the welfare of laying hens that are housed in non-cage or furnished caged systems.

  14. Do laying hens with keel bone fractures experience pain?

    Directory of Open Access Journals (Sweden)

    Mohammed A F Nasr

    Full Text Available The European ban on battery cages has forced a change towards the use of non-cage or furnished cage systems, but unexpectedly this has been associated with an increased prevalence of keel bone fractures in laying hens. Bone fractures are acutely painful in mammals, but the effect of fractures on bird welfare is unclear. We recently reported that keel bone fractures have an effect on bird mobility. One possible explanation for this is that flying becomes mechanically impaired. However it is also possible that if birds have a capacity to feel pain, then ongoing pain resulting from the fracture could contribute to decreased mobility. The aim was to provide proof of concept that administration of appropriate analgesic drugs improves mobility in birds with keel fracture; thereby contributing to the debate about the capacity of birds to experience pain and whether fractures are associated with pain in laying hens. In hens with keel fractures, butorphanol decreased the latency to land from perches compared with latencies recorded for these hens following saline (mean (SEM landing time (seconds birds with keel fractures treated with butorphanol and saline from the 50, 100 and 150 cm perch heights respectively 1.7 (0.3, 2.2 (0.3, p = 0.05, 50 cm; 12.5 (6.6, 16.9 (6.7, p = 0.03, 100 cm; 20.6 (7.4, 26.3 (7.6, p = 0.02 150 cm. Mobility indices were largely unchanged in birds without keel fractures following butorphanol. Critically, butorphanol can be considered analgesic in our study because it improved the ability of birds to perform a complex behaviour that requires both motivation and higher cognitive processing. This is the first study to provide a solid evidential base that birds with keel fractures experience pain, a finding that has significant implications for the welfare of laying hens that are housed in non-cage or furnished caged systems.

  15. Phase diagram of a model of the protein amelogenin

    Science.gov (United States)

    Haaga, Jason; Pemberton, Elizabeth; Gunton, J. D.; Rickman, J. M.

    2016-08-01

    There has been considerable recent interest in the self-assembly and phase behavior of models of colloidal and protein particles with anisotropic interactions. One example of particular interest is amelogenin, an important protein involved in the formation of dental enamel. Amelogenin is primarily hydrophobic with a 25-residue charged C-terminus tail. This protein undergoes a hierarchical assembly process that is crucial to mineral deposition, and experimental work has demonstrated that the deletion of the C-terminus tail prevents this self-assembly. A simplified model of amelogenin has been proposed in which the protein is treated as a hydrophobic sphere, interacting via the Asakura-Oosawa (AO) potential, with a tethered point charge on its surface. In this paper, we examine the effect of the Coulomb interaction between the point charges in altering the phase diagram of the AO model. For the parameter case specific to amelogenin, we find that the previous in vitro experimental and model conditions correspond to the system being near the low-density edge of the metastable region of the phase diagram. Our study illustrates more generally the importance of understanding the phase diagram for proteins, in that the kinetic pathway for self-assembly and the resulting aggregate morphology depends on the location of the initial state in the phase diagram.

  16. The evolution of the protein synthesis system. I - A model of a primitive protein synthesis system

    Science.gov (United States)

    Mizutani, H.; Ponnamperuma, C.

    1977-01-01

    A model is developed to describe the evolution of the protein synthesis system. The model is comprised of two independent autocatalytic systems, one including one gene (A-gene) and two activated amino acid polymerases (O and A-polymerases), and the other including the addition of another gene (N-gene) and a nucleotide polymerase. Simulation results have suggested that even a small enzymic activity and polymerase specificity could lead the system to the most accurate protein synthesis, as far as permitted by transitions to systems with higher accuracy.

  17. Bayesian Proteoform Modeling Improves Protein Quantification of Global Proteomic Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Webb-Robertson, Bobbie-Jo M.; Matzke, Melissa M.; Datta, Susmita; Payne, Samuel H.; Kang, Jiyun; Bramer, Lisa M.; Nicora, Carrie D.; Shukla, Anil K.; Metz, Thomas O.; Rodland, Karin D.; Smith, Richard D.; Tardiff, Mark F.; McDermott, Jason E.; Pounds, Joel G.; Waters, Katrina M.

    2014-12-01

    As the capability of mass spectrometry-based proteomics has matured, tens of thousands of peptides can be measured simultaneously, which has the benefit of offering a systems view of protein expression. However, a major challenge is that with an increase in throughput, protein quantification estimation from the native measured peptides has become a computational task. A limitation to existing computationally-driven protein quantification methods is that most ignore protein variation, such as alternate splicing of the RNA transcript and post-translational modifications or other possible proteoforms, which will affect a significant fraction of the proteome. The consequence of this assumption is that statistical inference at the protein level, and consequently downstream analyses, such as network and pathway modeling, have only limited power for biomarker discovery. Here, we describe a Bayesian model (BP-Quant) that uses statistically derived peptides signatures to identify peptides that are outside the dominant pattern, or the existence of multiple over-expressed patterns to improve relative protein abundance estimates. It is a research-driven approach that utilizes the objectives of the experiment, defined in the context of a standard statistical hypothesis, to identify a set of peptides exhibiting similar statistical behavior relating to a protein. This approach infers that changes in relative protein abundance can be used as a surrogate for changes in function, without necessarily taking into account the effect of differential post-translational modifications, processing, or splicing in altering protein function. We verify the approach using a dilution study from mouse plasma samples and demonstrate that BP-Quant achieves similar accuracy as the current state-of-the-art methods at proteoform identification with significantly better specificity. BP-Quant is available as a MatLab ® and R packages at https://github.com/PNNL-Comp-Mass-Spec/BP-Quant.

  18. A polaron model for electron transfer in globular proteins.

    Science.gov (United States)

    Chuev, G N; Lakhno, V D

    1993-07-07

    Polaron models have been considered for the electron states in protein globules existing in a solvent. These models account for two fundamental effects, viz, polarization interaction of an electron with the conformational vibrations and the heterogeneity of the medium. Equations have been derived to determine the electron state in a protein globule. The parameters of this state show that it is an extended state with an energy of 2 eV. The electron transfer rate for cyt C self-exchange reaction has been calculated in the polaron model. Reorganization energy, tunneling matrix element and the rate constant have also been estimated. The results are compared with experimental data. The influence of model parameters on the significance of the data obtained has been studied. The potentialities of the model are discussed.

  19. A simple probabilistic model of multibody interactions in proteins

    DEFF Research Database (Denmark)

    Johansson, Kristoffer Enøe; Hamelryck, Thomas

    2013-01-01

    predictions. Our coarse-grained model is compared to state-of-art methods that use full atomic detail. This article illustrates how the use of simple probabilistic models can lead to new opportunities in the treatment of nonlocal interactions in knowledge-based protein structure prediction and design....... beyond pairwise interactions have been described, the formulation of a general multibody potential is seen as intractable due to the perceived limited amount of data. In this article, we show that it is possible to formulate a probabilistic model of higher order interactions in proteins, without...... arbitrarily limiting the number of contacts. The success of this approach is based on replacing a naive table-based approach with a simple hierarchical model involving suitable probability distributions and conditional independence assumptions. The model captures the joint probability distribution of an amino...

  20. Unifying model for two-state and downhill protein folding

    Science.gov (United States)

    Mi, D.; Meng, W. Q.; Sun, Y. Q.

    2011-04-01

    A protein-folding model is proposed at the amino acid level, in which the folding process is divided into two successive stages: the rate-determining step, dominated by the “stochastic interactions”of solvent molecules, and the rapid phase, dominated by the “order interactions”among atoms in polypeptide. The master equation approach is used to investigate the folding kinetics, and an analytical treatment of the master equation yields a simple three-parameter expression for folding time. It is found that both two-state and downhill protein-folding kinetics can be described by a unifying model.

  1. A generative, probabilistic model of local protein structure

    DEFF Research Database (Denmark)

    Boomsma, Wouter; Mardia, Kanti V.; Taylor, Charles C.;

    2008-01-01

    Despite significant progress in recent years, protein structure prediction maintains its status as one of the prime unsolved problems in computational biology. One of the key remaining challenges is an efficient probabilistic exploration of the structural space that correctly reflects the relative...... conformational stabilities. Here, we present a fully probabilistic, continuous model of local protein structure in atomic detail. The generative model makes efficient conformational sampling possible and provides a framework for the rigorous analysis of local sequence-structure correlations in the native state...

  2. Protein-binding site prediction based on three-dimensional protein modeling.

    Science.gov (United States)

    Oh, Mina; Joo, Keehyoung; Lee, Jooyoung

    2009-01-01

    Structural information of a protein can guide one to understand the function of the protein, and ligand binding is one of the major biochemical functions of proteins. We have applied a two-stage template-based ligand binding site prediction method to CASP8 targets and achieved high quality results with accuracy/coverage = 70/80 (LEE). First, templates are used for protein structure modeling and then for binding site prediction by structural clustering of ligand-containing templates to the predicted protein model. Remarkably, the results are only a few percent worse than those one can obtain from native structures, which were available only after the prediction. Prediction was performed without knowing identity of ligands, and consequently, in many cases the ligand molecules used for prediction were different from the actual ligands, and yet we find that the prediction was quite successful. The current approach can be easily combined with experiments to investigate protein activities in a systematic way. Copyright 2009 Wiley-Liss, Inc.

  3. Predicting protein subcellular locations using hierarchical ensemble of Bayesian classifiers based on Markov chains

    Directory of Open Access Journals (Sweden)

    Eils Roland

    2006-06-01

    Full Text Available Abstract Background The subcellular location of a protein is closely related to its function. It would be worthwhile to develop a method to predict the subcellular location for a given protein when only the amino acid sequence of the protein is known. Although many efforts have been made to predict subcellular location from sequence information only, there is the need for further research to improve the accuracy of prediction. Results A novel method called HensBC is introduced to predict protein subcellular location. HensBC is a recursive algorithm which constructs a hierarchical ensemble of classifiers. The classifiers used are Bayesian classifiers based on Markov chain models. We tested our method on six various datasets; among them are Gram-negative bacteria dataset, data for discriminating outer membrane proteins and apoptosis proteins dataset. We observed that our method can predict the subcellular location with high accuracy. Another advantage of the proposed method is that it can improve the accuracy of the prediction of some classes with few sequences in training and is therefore useful for datasets with imbalanced distribution of classes. Conclusion This study introduces an algorithm which uses only the primary sequence of a protein to predict its subcellular location. The proposed recursive scheme represents an interesting methodology for learning and combining classifiers. The method is computationally efficient and competitive with the previously reported approaches in terms of prediction accuracies as empirical results indicate. The code for the software is available upon request.

  4. Homology modelling of protein-protein complexes: a simple method and its possibilities and limitations

    Directory of Open Access Journals (Sweden)

    Simonson Thomas

    2008-10-01

    Full Text Available Abstract Background Structure-based computational methods are needed to help identify and characterize protein-protein complexes and their function. For individual proteins, the most successful technique is homology modelling. We investigate a simple extension of this technique to protein-protein complexes. We consider a large set of complexes of known structures, involving pairs of single-domain proteins. The complexes are compared with each other to establish their sequence and structural similarities and the relation between the two. Compared to earlier studies, a simpler dataset, a simpler structural alignment procedure, and an additional energy criterion are used. Next, we compare the Xray structures to models obtained by threading the native sequence onto other, homologous complexes. An elementary requirement for a successful energy function is to rank the native structure above any threaded structure. We use the DFIREβ energy function, whose quality and complexity are typical of the models used today. Finally, we compare near-native models to distinctly non-native models. Results If weakly stable complexes are excluded (defined by a binding energy cutoff, as well as a few unusual complexes, a simple homology principle holds: complexes that share more than 35% sequence identity share similar structures and interaction modes; this principle was less clearcut in earlier studies. The energy function was then tested for its ability to identify experimental structures among sets of decoys, produced by a simple threading procedure. On average, the experimental structure is ranked above 92% of the alternate structures. Thus, discrimination of the native structure is good but not perfect. The discrimination of near-native structures is fair. Typically, a single, alternate, non-native binding mode exists that has a native-like energy. Some of the associated failures may correspond to genuine, alternate binding modes and/or native complexes that

  5. Validation of protein models by a neural network approach

    Directory of Open Access Journals (Sweden)

    Fantucci Piercarlo

    2008-01-01

    Full Text Available Abstract Background The development and improvement of reliable computational methods designed to evaluate the quality of protein models is relevant in the context of protein structure refinement, which has been recently identified as one of the bottlenecks limiting the quality and usefulness of protein structure prediction. Results In this contribution, we present a computational method (Artificial Intelligence Decoys Evaluator: AIDE which is able to consistently discriminate between correct and incorrect protein models. In particular, the method is based on neural networks that use as input 15 structural parameters, which include energy, solvent accessible surface, hydrophobic contacts and secondary structure content. The results obtained with AIDE on a set of decoy structures were evaluated using statistical indicators such as Pearson correlation coefficients, Znat, fraction enrichment, as well as ROC plots. It turned out that AIDE performances are comparable and often complementary to available state-of-the-art learning-based methods. Conclusion In light of the results obtained with AIDE, as well as its comparison with available learning-based methods, it can be concluded that AIDE can be successfully used to evaluate the quality of protein structures. The use of AIDE in combination with other evaluation tools is expected to further enhance protein refinement efforts.

  6. Discrete and continuous models of protein sorting in the Golgi

    Science.gov (United States)

    Gong, Haijun; Schwartz, Russell

    2009-03-01

    The Golgi apparatus plays an important role in processing and sorting proteins and lipids. Golgi compartments constantly exchange material with each other and with other cellular components, allowing them to maintain and reform distinct identities despite dramatic changes in structure and size during cell division, development and osmotic stress. We have developed two minimal models of membrane and protein exchange in the Golgi --- a discrete, stochastic model [1] and a continuous ordinary differential equation (ODE) model --- both based on two fundamental mechanisms: vesicle-coat-mediated selective concentration of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins during vesicle formation and SNARE-mediated selective fusion of vesicles. Both show similar ability to establish and maintain distinct identities over broad parameter ranges, but they diverge in extreme conditions where Golgi collapse and reassembly may be observed. By exploring where the models differ, we hope to better identify those features essential to minimal models of various Golgi behaviors. [1] H. Gong, D. Sengupta, A. D. Linstedt, R. Schwartz. Biophys J. 95: 1674-1688, 2008.

  7. Laying hen performance and well-being over two flock cycles on different litter substrates in an aviary housing

    Science.gov (United States)

    The momentum to move toward aviary housing has continued to increase in the past eight months. The pressure to find consistent bedding sources for meat birds may impact litter substrate for the laying hen industry as the number of cage-free hens increases in the next nine years. Molting laying hens ...

  8. Examination of egg number and egg weight variables and their effects on daily management in aviary systems for laying hens

    NARCIS (Netherlands)

    Lokhorst, C.; Keen, A.

    1995-01-01

    1. Characteristics of egg numbers and mean egg weight were examined for their usefulness in the daily management of aviary systems for laying hens. 2. A number of 3238 brown Isabrown/Warren hens were housed in 1 compartment, a separated part of the house where the hens could move around freely, of a

  9. Mixed housing of different genetic lines of laying hens negatively affects feather pecking and fear related behaviour

    NARCIS (Netherlands)

    Uitdehaag, K.A.; Rodenburg, T.B.; Bolhuis, J.E.; Decuypere, E.; Komen, J.

    2009-01-01

    Adult laying hens from Rhode Island Red (RIR) origin both express lower levels of feather pecking and lower fear responses towards a novel object than laying hens from White Leghorn (WL) origin. The present study investigated whether mixed housing of RIR and WL laying hens would affect their behavio

  10. A resource for benchmarking the usefulness of protein structure models

    Directory of Open Access Journals (Sweden)

    Carbajo Daniel

    2012-08-01

    Full Text Available Abstract Background Increasingly, biologists and biochemists use computational tools to design experiments to probe the function of proteins and/or to engineer them for a variety of different purposes. The most effective strategies rely on the knowledge of the three-dimensional structure of the protein of interest. However it is often the case that an experimental structure is not available and that models of different quality are used instead. On the other hand, the relationship between the quality of a model and its appropriate use is not easy to derive in general, and so far it has been analyzed in detail only for specific application. Results This paper describes a database and related software tools that allow testing of a given structure based method on models of a protein representing different levels of accuracy. The comparison of the results of a computational experiment on the experimental structure and on a set of its decoy models will allow developers and users to assess which is the specific threshold of accuracy required to perform the task effectively. Conclusions The ModelDB server automatically builds decoy models of different accuracy for a given protein of known structure and provides a set of useful tools for their analysis. Pre-computed data for a non-redundant set of deposited protein structures are available for analysis and download in the ModelDB database. Implementation, availability and requirements Project name: A resource for benchmarking the usefulness of protein structure models. Project home page: http://bl210.caspur.it/MODEL-DB/MODEL-DB_web/MODindex.php. Operating system(s: Platform independent. Programming language: Perl-BioPerl (program; mySQL, Perl DBI and DBD modules (database; php, JavaScript, Jmol scripting (web server. Other requirements: Java Runtime Environment v1.4 or later, Perl, BioPerl, CPAN modules, HHsearch, Modeller, LGA, NCBI Blast package, DSSP, Speedfill (Surfnet and PSAIA. License: Free. Any

  11. Super-secondary structures and modeling of protein folds.

    Science.gov (United States)

    Efimov, Alexander V

    2013-01-01

    A characteristic feature of the polypeptide chain is its ability to form a restricted set of commonly occurring folding units composed of two or more elements of secondary structure that are adjacent along the chain. Some of these super-secondary structures exhibit a unique handedness and a unique overall fold irrespective of whether they occur in homologous or nonhomologous proteins. Such super-secondary structures are of particular value since they can be used as starting structures in protein modeling. The larger protein folds can be obtained by stepwise addition of other secondary structural elements to the starting structures taking into account a set of simple rules inferred from known principles of protein structure.

  12. Extracting protein alignment models from the sequence database.

    Science.gov (United States)

    Neuwald, A F; Liu, J S; Lipman, D J; Lawrence, C E

    1997-05-01

    Biologists often gain structural and functional insights into a protein sequence by constructing a multiple alignment model of the family. Here a program called Probe fully automates this process of model construction starting from a single sequence. Central to this program is a powerful new method to locate and align only those, often subtly, conserved patterns essential to the family as a whole. When applied to randomly chosen proteins, Probe found on average about four times as many relationships as a pairwise search and yielded many new discoveries. These include: an obscure subfamily of globins in the roundworm Caenorhabditis elegans ; two new superfamilies of metallohydrolases; a lipoyl/biotin swinging arm domain in bacterial membrane fusion proteins; and a DH domain in the yeast Bud3 and Fus2 proteins. By identifying distant relationships and merging families into superfamilies in this way, this analysis further confirms the notion that proteins evolved from relatively few ancient sequences. Moreover, this method automatically generates models of these ancient conserved regions for rapid and sensitive screening of sequences.

  13. Computational Modeling for the Activation Cycle of G-proteins by G-protein-coupled Receptors

    Directory of Open Access Journals (Sweden)

    Yifei Bao

    2010-10-01

    Full Text Available In this paper, we survey five different computational modeling methods. For comparison, we use the activation cycle of G-proteins that regulate cellular signaling events downstream of G-protein-coupled receptors (GPCRs as a driving example. Starting from an existing Ordinary Differential Equations (ODEs model, we implement the G-protein cycle in the stochastic Pi-calculus using SPiM, as Petri-nets using Cell Illustrator, in the Kappa Language using Cellucidate, and in Bio-PEPA using the Bio-PEPA eclipse plug in. We also provide a high-level notation to abstract away from communication primitives that may be unfamiliar to the average biologist, and we show how to translate high-level programs into stochastic Pi-calculus processes and chemical reactions.

  14. USING RICE BRAN IN LAYING HEN DIETS

    Directory of Open Access Journals (Sweden)

    H ERSIN SAMLI

    2006-10-01

    Full Text Available Rice bran is an energy and protein rich ingredient used in poultry feeding. To balance energy and protein requirements. The purpose of this study is to examine the effects of rice bran on performance and egg quality during peak production of a commercial White laying strain of 22 week of age. Dietary treatments were consisted by inclusion of rice bran at 0, 5, 10 and 15% levels. Each treatment had 6 reps in which 12 birds were randomly assigned in wired fl oor battery cages equipped with nipple drinkers and through feeders. Layers accessed to feed and water freely. Lighting regimen was adjusted to 16h light/8h dark. The experiment lasted for 10 weeks. Overall results of the present experiment indicated that rice bran could be included up to 10% without any adverse affect on laying performance, egg quality and digestive organs.

  15. Ammonia emission from aviary housing systems for laying hens. Inventory, characteristics and solutions.

    NARCIS (Netherlands)

    Groot Koerkamp, P.W.G.

    1998-01-01

    The development and practical application of welfare friendly aviary housing systems for laying hens, that generally emit more ammonia per hen than battery cage housing systems, would conflict with the Dutch policy to substantially reduce the total emission of ammonia from animal husbandry.This thes

  16. The value of feed consumption data for breeding in laying hens.

    NARCIS (Netherlands)

    Luiting, P.

    1991-01-01

    The results of statistical and experimental analyses of residual feed consumption (RFC) in White Leghorn laying hens are presented. RFC is defined as the difference between the observed feed consumption of a hen and its feed consumption predicted from its egg mass production, body weight gain and me

  17. Analysis on differential expressed genes of ovarian tissue between high- and low-yield laying hen.

    Science.gov (United States)

    Chen, Wei; Song, Ling-Jun; Zeng, Yong-Qing; Yang, Yun; Wang, Hui

    2013-01-01

    In order to elucidate molecular genetic mechanism of laying hen reproduction at the transcriptional level and the structure of significantly differential genes, the mRNA differential display and reverse northern dot-blot were used to detect the differential expression of genes in the ovary tissue of low-yield laying hens and high-yield laying hens in the present study. Sixteen 32-week-old CAU-pink laying hens divided into two groups were used and the laying performance was measured. The results showed that only the egg numbers were significantly different between the two groups; and from 15 primer pairs, a total of 336 bands were displayed of which 59 cDNA bands were found to be differentially expressed in both high-yield and low-yield laying hen. The sequence analysis indicated that the expression of such bands as H-AP5, H-P5, and H-P4 was significantly potentiated in high-yield laying hen using primer pairs AP5/HT11G, P5/HT11G and P4/HT11G and these transcripts had high homology (98%) to HoxDb, HoxCa, and HoxBa, respectively. The differentially expressed gene fragments may be relevant to the progression of the high-yield hens to the egg-laying stage. And further study is required to elucidate the molecular function to improve the productivity of laying hens.

  18. Corticosterone metabolites in laying hen droppings-Effects of fiber enrichment, genotype, and daily variations.

    Science.gov (United States)

    Alm, M; Holm, L; Tauson, R; Wall, H

    2014-10-01

    There is growing interest and concern for animal welfare in commercial poultry production. To evaluate stress and welfare in an objective and noninvasive way, fecal corticosterone metabolites (FCM) in droppings can be analyzed. However, the influence of diet, genotype, and daily variations in FCM and production of droppings in laying hens has been poorly investigated. This study examined the effect of insoluble fiber by adding 3% ground straw pellets to the feed to Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB) hens housed in furnished cages between 20 and 40 wk of age. In total, 960 hens were included in the study. Droppings were collected 4 times per day for 3 consecutive days and analyzed by corticosterone immunoassay. Biological validation confirmed the ability of the assay to detect changes in FCM levels. Inclusion of straw pellets in the feed increased FCM concentration in both hen genotypes and increased excretion rate of FCM in LB hens. The LB hens also produced greater amounts of droppings than LSL hens. Both FCM levels and production of droppings varied during the day, although no distinct diurnal rhythm was found. These findings demonstrate that when using FCM to evaluate stress and welfare in laying hens, many factors (e.g., diet, genotype used, and so on) need to be taken into account to allow accurate interpretation of the results. In addition, under certain conditions, excretion rate of FCM might be more appropriate to use compared with FCM concentration.

  19. Sand intake by laying hens and its effect on egg production parameters

    NARCIS (Netherlands)

    Meulen, van der J.; Kwakernaak, C.; Kan, C.A.

    2008-01-01

    Soil intake may be the most prominent source of environmental contaminants for free range and organic hens, but there are no quantitative data concerning soil intake by domestic hens. Consumption of soil of 14¿32 g a day can be estimated from literature, but such a dilution of nutrient intake seems

  20. Cytological Evaluation of Bone Marrow in Normal Laying Hens and those With Lymphoid Leukosis

    Directory of Open Access Journals (Sweden)

    H.I. Al-Sadi and E.Y. Hussein

    Full Text Available The purpose of this study was to evaluate cytologically the bone marrow (and peripheral blood of adult laying hens affected with lymphoid leukosis. Diagnosis of the neoplasm was made on the basis of clinical history, signs and symptoms and pathology. Only histologically confirmed cases were included in the study. Examination of blood smears revealed +2 heterophil toxicity and the presence of large numbers of reactive (blast – transformed lymphocytes. Smears that were prepared from the bone marrow showed increased numbers of hemopoietic cells. The total erythrocyte count (TEC, hemoglobin percentage (Hb% , hemoglobin concentration (Hb conc., packed cell volume (PCV and the mean corpuscular hemoglobin concentration (MCHC values were significantly higher (P<0.01 in hens with lymphoid leukosis than in apparently normal hens. The mean corpuscular volume (MCV and the mean corpuscular hemoglobin (MCH were significantly lower (P< 0.01 in hens with lymphoid leukosis than in apparently normal hens. Results of the leukogram indicated that the total leukocyte count (TLC and the percentage (% of lymphocytes were significantly higher (P < 0.01 in hens with lymphoid leukosis than in apparently normal hens. From results of this study it was concluded that cytological evaluation of bone marrow may prove to be a simple , rapid , and useful tool in the diagnosis of lymphoid leukosis in laying hens. [Veterinary World 2010; 3(11.000: 497-499

  1. Quality of foraging material and the effect on hens feed intake, egg production and - quality

    DEFF Research Database (Denmark)

    Steenfeldt, Sanna; Hammershøj, Marianne

    2010-01-01

    In a project with organic egg laying hens, the effect of different kind of foraging material was studied on feed intake, egg-production and -quality. Udgivelsesdato: August......In a project with organic egg laying hens, the effect of different kind of foraging material was studied on feed intake, egg-production and -quality. Udgivelsesdato: August...

  2. Specific characteristics of the aviary housing system affect plumage condition, mortality and production in laying hens

    NARCIS (Netherlands)

    Heerkens, J.L.T.; Delezie, Evelyne; Kempen, Ine; Zoons, Johan; Ampe, Bart; Rodenburg, T.B.; Tuyttens, F.A.M.

    2015-01-01

    Feather pecking and high mortality levels are significant welfare problems in non-cage housing systems for laying hens. The aim of this study was to identify husbandry-related risk factors for feather damage, mortality, and egg laying performance in laying hens housed in the multi-tier non-cage h

  3. ECONOMIC ANALYSIS LAYING HENS FARM AT FARM HARMA NGEMPLAK DISTRICT, SLEMAN REGENCY

    Directory of Open Access Journals (Sweden)

    Pes Murib

    2014-01-01

    Full Text Available Laying Poultry is one of local farm potential that can developed for years to come because they have a favorable earnings outlook for entrepreneurs laying hens. This study aimed to: 1 determine factors that influence egg production, 2 knowing revenues laying hens, 3 knowing feasibility of laying hens. Subjects in this study were laying poultry Farm Harma at Banjarharjo, Sleman. Data in this research obtained through observation, interviews, and recording. Used analysis: 1 analysis of Factors Affecting Production of Livestock Laying Chickens used Multiple Linear Regression Analysis, 2 Analysis of revenues, and 3 analysis of feasibility of laying hens used analysis of R/C. Results: 1 factors of production which includes amount of labor, housing, medicines, seeds, and feed together affect production of laying hens. Then individual variables showed that only drugs that do not significantly affect production of laying hens. While variable amount of labor, cages, seed and feed significantly affect production of laying hens, 2 gross income received by farmers is IDR 277,525,208, while net income amounted to IDR 105,214,234, and 3 rated R/C ratio of 1.52 which can be concluded that business of laying hens at Farm Harma Banjarharjo worth effort.

  4. Effects of dietary energy content on the performance of laying hens in furnished and conventional cages.

    Science.gov (United States)

    Valkonen, E; Venäläinen, E; Rossow, L; Valaja, J

    2008-05-01

    This study examined the effects of dietary energy content on the egg production and egg quality of hens kept in 3-hen conventional cages or 8-hen furnished cages. A total of 1,088 Lohmann Selected Leghorn hens were housed in either furnished or conventional cages and offered low- or high-energy diets (from 2,342 to 2,414 kcal/kg or from 2,581 to 2,629 kcal/kg) during 3 consecutive feeding phases of 20, 16, and 16 wk, respectively. The same dietary energy effects were observed in both cage systems. The hens that received the low-energy diet consumed more feed (P cages than in conventional cages (P cages at the beginning of the experiment, these hens consumed more feed during the first feeding phase than the hens in conventional cages. During the third feeding phase, the hens in furnished cages consumed less feed than those in conventional cages (P cage types. The results of this study confirm the results of previous studies providing evidence of equal production rates and feed conversion ratios in furnished and conventional cages.

  5. Study on the Metaphors in Chang Hen Ge from the Perspectiveof Conceptual Metaphor Theory

    Institute of Scientific and Technical Information of China (English)

    李园园

    2013-01-01

      This thesis aims to study the phenomenon of metaphors in the Bai Juyi's Chang Hen Ge so as to explore the cognitive mechanism existing in the interpretation of the metaphors in Chang Hen Ge. We can conclude that the translation of metaphor plays an important role in the poems.

  6. Heritability of feather pecking and open-field response of laying hens at two different ages

    NARCIS (Netherlands)

    Rodenburg, T.B.; Buitenhuis, A.J.; Ask, B.; Uitdehaag, K.A.; Koene, P.; Poel, van der J.J.; Bovenhuis, H.

    2003-01-01

    The objective of the current study was to estimate heritabilities. (h(2)) of feather pecking and open-field response of laying hens at two different ages. An F-2 cross, originating from a high and a low feather pecking line of laying hens, was used for the experiment. Each of the 630 birds of the F-

  7. Effects of essential oils on performance, egg quality, nutrient digestibility and yolk fatty acid profile in laying hens

    Directory of Open Access Journals (Sweden)

    Xuemei Ding

    2017-06-01

    Full Text Available The study was conducted to investigate the effect of essential oils on performance, egg quality, nutrient digestibility and yolk fatty acid profile in laying hens. A total of 960 Lohmann laying hens aged 53 weeks were enrolled, under 4 different treatment diets supplemented with 0, 50, 100 and 150 mg/kg essential oils (Enviva EO, Dupont Nutrition Biosciences ApS, Denmark, respectively. Each treatment was replicated 8 times with 30 birds each. Birds were fed dietary treatment diets for 12 weeks (54 to 65 weeks. For data recording and analysis, a 12-week period was divided into 3 periods of 4 weeks' duration each: period 1 (54 to 57 weeks, period 2 (58 to 61 weeks, and period 3 (62 to 65 weeks. For the diet supplemented with Enviva EO, hen-day egg production and the feed conversion ratio (FCR were significantly improved (P < 0.05 at weeks 58 to 61, and the eggshell thickness was significantly increased (P < 0.05 at week 65. However, egg production, egg weight, feed intake, FCR and other egg quality parameters (albumen height, Haugh unit, egg yolk color and eggshell strength were not affected by the dietary treatment. In addition, compared with the control diet, protein digestibility in the 100 mg/kg Enviva EO treatment group was significantly increased (P < 0.05, and fat digestibility in the 100 and 150 mg/kg Enviva EO treatment groups was significantly decreased (P < 0.05, but Enviva EO had no effect on energy apparent digestibility. Saturated fatty acid (SFA and monounsaturated fatty acid (MUFA gradually decreased and polyunsaturated fatty acid (PUFA increased with Enviva EO supplementation, but the difference was not significant. The data suggested that the supplementation of essential oils (Enviva EO in laying hen diet did not show a significant positive effect on performance and yolk fatty acid composition but it tended to increase eggshell thickness and protein digestibility, especially at the dose of 50 mg/kg.

  8. Simulation of heat exchanger network (HEN) and planning the optimum cleaning schedule

    Energy Technology Data Exchange (ETDEWEB)

    Sanaye, Sepehr [Energy Systems Improvement Laboratory, Mechanical Engineering Department, Iran University of Science and Technology (IUST), Narmak, Tehran 16488 (Iran, Islamic Republic of)]. E-mail: sepehr@iust.ac.ir; Niroomand, Behzad [Energy Systems Improvement Laboratory, Mechanical Engineering Department, Iran University of Science and Technology (IUST), Narmak, Tehran 16488 (Iran, Islamic Republic of)

    2007-05-15

    Modeling and simulation of heat exchanger networks for estimating the amount of fouling, variations in overall heat transfer coefficient, and variations in outlet temperatures of hot and cold streams has a significant effect on production analysis. In this analysis, parameters such as the exchangers' types and arrangements, their heat transfer surface areas, mass flow rates of hot and cold streams, heat transfer coefficients and variations of fouling with time are required input data. The main goal is to find the variations of the outlet temperatures of the hot and cold streams with time to plan the optimum cleaning schedule of heat exchangers that provides the minimum operational cost or maximum amount of savings. In this paper, the simulation of heat exchanger networks is performed by choosing an asymptotic fouling function. Two main parameters in the asymptotic fouling formation model, i.e. the decay time of fouling formation ({tau}) and the asymptotic fouling resistance (R{sub f}{sup {approx}}) were obtained from empirical data as input parameters to the simulation relations. These data were extracted from the technical history sheets of the Khorasan Petrochemical Plant to guaranty the consistency between our model outputs and the real operating conditions. The output results of the software program developed, including the variations with time of the outlet temperatures of the hot and cold streams, the heat transfer coefficient and the heat transfer rate in the exchangers, are presented for two case studies. Then, an objective function (operational cost) was defined, and the optimal cleaning schedule of the HEN (heat exchanger network) in the Urea and Ammonia units were found by minimizing the objective function using a numerical search method. Based on this minimization procedure, the decision was made whether a heat exchanger should be cleaned or continue to operate. The final result was the most cost effective plan for the HEN cleaning schedule. The

  9. Yolk sac nutrient composition and fat uptake in late-term embryos in eggs from young and old broiler breeder hens.

    Science.gov (United States)

    Yadgary, L; Cahaner, A; Kedar, O; Uni, Z

    2010-11-01

    In the present study, we examined the composition, amount, and uptake of yolk nutrients [fat, protein, water, and carbohydrates (COH)] during incubation of eggs from 30- and 50-wk-old broiler breeder hens. Eggs were sampled at embryonic d 0 (fresh eggs), 13, 15, 17, 19, and 21 (hatch). Egg, embryo, yolk content, and yolk sac membrane were weighed, and the yolk sac (YS; i.e., yolk content + yolk sac membrane) composition was analyzed. From 30 to 50 wk of age, the albumen weight increased by 13.3%, whereas the yolk increased by more than 40%. The proportion of fat in the fresh yolk of the 30-wk-old group was 23.8% compared with 27.4% in the 50-wk-old group, whereas the proportion of protein was 17.9% compared with 15.6%, respectively. During incubation, results indicated that water and protein infiltrated from other egg compartments to the YS. Accordingly, the calculated change in the content of water and protein between fresh yolk and sampled YS does not represent the true uptake of these components from the YS to the embryo, and only fat uptake from the YS can be accurately estimated. By embryonic d 15, fat uptake relative to embryo weight was lower in the 30-wk-old group than in the 50-wk-old group. However, by embryonic d 21, embryos of both groups reached similar relative fat uptake, suggesting that to hatch, embryos must attain a certain amount of fat as a source of energy for the hatching process. The amount of COH in the YS increased similarly during incubation in eggs from hens of both ages, reaching a peak at embryonic d 19, suggesting COH synthesis in the YS. At hatch, the amount of protein, water, and COH in the residual YS, relative to the weight of the yolk-free chick, was similar in eggs from young and old hens. However, chicks from the younger hens had less fat in the YS for their immediate posthatch nutrition compared with those from the older hens.

  10. Beta-endorphin regulation of LHRH release at the median eminence level: immunocytochemical and physiological evidence in hens.

    Science.gov (United States)

    Contijoch, A M; Malamed, S; Sarkar, D K; Advis, J P

    1993-01-01

    We studied the effect that beta-endorphin (beta END) might have at the median eminence (ME) on luteinizing hormone (LH)-releasing hormone (LHRH) during the ovulatory cycle of domestic hens. Thus, we assessed (a) the immunocytochemical distribution of beta END and LHRH in the hen ME, (b) the temporal changes in ME and preoptic area (POA) LHRH and beta END content, in both a spontaneous and a premature C2 ovulatory model. The premature C2 ovulation occurs 6-7 h after the administration of progesterone (P4) injected 14 h before the spontaneous second (C2) ovulation of a sequence and therefore 7-8 h earlier than expected, (c) the ME in vitro release of beta END in both models, and (d) the effect of beta END and naloxone on in vitro ME-LHRH release in the two models. In the hen, beta END cell bodies are located in the periarcuate area with axons projecting to both the ME and the POA. LHRH perikarya are located in the medial POA and anterior hypothalamus and project to the ME and infundibulum through the ventrolateral hypothalamus. In the spontaneous C2 ovulatory model, both beta END and LHRH content in the ME remained unchanged during the 14 h preceding the C2 ovulation. However, POA-LHRH content was increasing at the time of the LH surge (4 h before the expected C2 ovulation) and remained elevated until the C2 ovulation occurred. In contrast, POA-beta END content was lowest at the time of the LH surge and remained low until the C2 ovulation occurred.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. QSAR Models for the Prediction of Plasma Protein Binding

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    Zeshan Amin

    2013-02-01

    Full Text Available Introduction: The prediction of plasma protein binding (ppb is of paramount importance in the pharmacokinetics characterization of drugs, as it causes significant changes in volume of distribution, clearance and drug half life. This study utilized Quantitative Structure – Activity Relationships (QSAR for the prediction of plasma protein binding. Methods: Protein binding values for 794 compounds were collated from literature. The data was partitioned into a training set of 662 compounds and an external validation set of 132 compounds. Physicochemical and molecular descriptors were calculated for each compound using ACD labs/logD, MOE (Chemical Computing Group and Symyx QSAR software packages. Several data mining tools were employed for the construction of models. These included stepwise regression analysis, Classification and Regression Trees (CART, Boosted trees and Random Forest. Results: Several predictive models were identified; however, one model in particular produced significantly superior prediction accuracy for the external validation set as measured using mean absolute error and correlation coefficient. The selected model was a boosted regression tree model which had the mean absolute error for training set of 13.25 and for validation set of 14.96. Conclusion: Plasma protein binding can be modeled using simple regression trees or multiple linear regressions with reasonable model accuracies. These interpretable models were able to identify the governing molecular factors for a high ppb that included hydrophobicity, van der Waals surface area parameters, and aromaticity. On the other hand, the more complicated ensemble method of boosted regression trees produced the most accurate ppb estimations for the external validation set.

  12. Exploring HP protein models using Wang-Landau sampling

    Science.gov (United States)

    Wuest, Thomas; Landau, David P.

    2008-03-01

    The hydrophobic-polar (HP) protein model has become a standard in assessing the efficiency of computational methods for protein structure prediction as well as for exploring the statistical physics of protein folding in general. Numerous methods have been proposed to address the challenges of finding minimal energy conformations within the rough energy landscape of this lattice heteropolymer model. However, only a few studies have been dedicated to the more revealing - but also more demanding - problem of estimating the density of states which allows access to thermodynamic properties of a system at any temperature. Here, we show that Wang-Landau sampling, in connection with a suitable move set (``pull moves''), provides a powerful route for the ground state search and the precise determination of the density of states for HP sequences (with up to 100 monomers) in both, two and three dimensions. Our procedure possesses an intrinsic simplicity and overcomes the inevitable limitations inherent in other more tailored approaches. The main advantage lies in its general applicability to a broad range of lattice protein models that go beyond the scope of the HP model.

  13. Effects of incubational humidity and hen age on embryo composition in broiler hatching eggs from young breeders.

    Science.gov (United States)

    Peebles, E D; Burnham, M R; Gardner, C W; Brake, J; Bruzual, J J; Gerard, P D

    2001-09-01

    There is a paucity of information regarding the influence of incubational humidity on the characteristics of broiler embryos from young hens that often produce chicks of marginal quality. Therefore, the effects of broiler breeder age (26, 28, and 30 wk) in young broiler breeders and incubator humidity (43, 53, and 63% RH) on embryonic growth between 16 and 21 d of incubation, hatching chick weight, and embryo and chick body compositions were evaluated. Hatching broiler chick BW at 21 d was lower for 26-wk-old breeders compared to those at 28 and 30 wk, and the lowest RH decreased relative wet embryo weight. Embryonic growth, on wet and DM bases, was increased in eggs from the youngest hens. Embryo moisture content (EM) was lower at 16, 17, and 19 d of incubation in eggs from breeders at 26 wk when compared to those at 28 wk of age. The effects of RH on embryo crude protein and fat composition were not consistent and varied with breeder age and length of incubation. It was demonstrated that broiler breeder age affects embryogenesis and hatching chick BW. Furthermore, EM was influenced by breeder age, and changes in incubational RH between 43 and 63% affected embryogenesis without having associated effects on EM or consistent effects on embryo crude fat and protein content. Nevertheless, a depression in embryogenesis with a reduction in incubational RH to 43% may accentuate poor posthatch performance of chicks from young breeders.

  14. SWISS-MODEL: modelling protein tertiary and quaternary structure using evolutionary information.

    Science.gov (United States)

    Biasini, Marco; Bienert, Stefan; Waterhouse, Andrew; Arnold, Konstantin; Studer, Gabriel; Schmidt, Tobias; Kiefer, Florian; Gallo Cassarino, Tiziano; Bertoni, Martino; Bordoli, Lorenza; Schwede, Torsten

    2014-07-01

    Protein structure homology modelling has become a routine technique to generate 3D models for proteins when experimental structures are not available. Fully automated servers such as SWISS-MODEL with user-friendly web interfaces generate reliable models without the need for complex software packages or downloading large databases. Here, we describe the latest version of the SWISS-MODEL expert system for protein structure modelling. The SWISS-MODEL template library provides annotation of quaternary structure and essential ligands and co-factors to allow for building of complete structural models, including their oligomeric structure. The improved SWISS-MODEL pipeline makes extensive use of model quality estimation for selection of the most suitable templates and provides estimates of the expected accuracy of the resulting models. The accuracy of the models generated by SWISS-MODEL is continuously evaluated by the CAMEO system. The new web site allows users to interactively search for templates, cluster them by sequence similarity, structurally compare alternative templates and select the ones to be used for model building. In cases where multiple alternative template structures are available for a protein of interest, a user-guided template selection step allows building models in different functional states. SWISS-MODEL is available at http://swissmodel.expasy.org/.

  15. Characterizing the histopathology of natural co-infection with Marek's disease virus and subgroup J avian leukosis virus in egg-laying hens.

    Science.gov (United States)

    Wen, Yawen; Huang, Qi; Yang, Chengcheng; Pan, Ling; Wang, Guijun; Qi, Kezong; Liu, Hongmei

    2017-09-01

    Marek's disease virus (MDV) and avian leukosis virus (ALV) are known to cause tumours in egg-laying hens. Here, we investigated the aetiology of tumours in a flock of egg-laying hens vaccinated against MDV. We carried out gross pathology and histopathological examinations of the diseased tissues, identified virus antigen and sequenced viral oncogenes to elucidate the cause of death in 21-22-wk-old hens. At necropsy, diseased hens had distinctly swollen livers, spleens, and proventriculus, and white tumour nodules in the liver. The spleen and liver had been infiltrated by lymphoid tumour cells, while the proventriculus had been infiltrated by both lymphoid tumour cells and myeloblastic cells. ALV-J and MDV were widely distributed in the proventricular gland cells, the lymphoid tumour cells in the liver and the spleen. In addition, positive ALV-J signals were also observed in parts of the reticular cells in the spleen. MDV and ALV-J antigens were observed in the same foci of the proventricular gland cells; however, the two antigens were not observed in the same foci from the spleen and liver. The amino acid sequence of the AN-1(the representative liver tumour tissue that was positive for both ALV-J and MDV) meq protein was highly similar to the very virulent MDV QD2014 from China. Compared to the ALV-J HPRS-103 reference strain, 10 amino acids (224-CTTEWNYYAY-233) were deleted from the gp85 protein of AN-1. We concluded that concurrent infection with MDV and ALV-J contributed to the tumorigenicity observed in the flock.

  16. New insights into implication of the SLIT/ROBO pathway in the prehierarchical follicle development of hen ovary.

    Science.gov (United States)

    Qin, N; Fan, X C; Zhang, Y Y; Xu, X X; Tyasi, T L; Jing, Y; Mu, F; Wei, M L; Xu, R F

    2015-09-01

    The SLIT/Roundabout (ROBO) pathway is involved in follicle development of mammalian ovary, and 2 secreted hormones activin A and inhibin A have potential roles in modulation of the SLIT/ROBO system, but the related actions remain poorly understood in bird. The aims of the present study were to examine the spatial and temporal expression of the SLIT ligand genes (SLIT1, SLIT2, and SLIT3) and their receptor ROBO1, ROBO2, ROBO3, and ROBO4 genes in various-sized prehierarchical follicles during hen ovary development and the effects of activin A and inhibin A on the expression of these genes in the cultured hen follicles. Our result demonstrated that the transcripts of the 3 SLIT genes were highly expressed in the developing follicles and expression patterns of the SLIT transcripts were different from those of ROBO genes detected by real-time quantitative reverse transcriptase PCR. Both SLIT and ROBO transcripts were predominantly expressed in oocytes and granulosa cells from the prehierarchichal follicles examined by in situ hybridization. The localization for SLIT and ROBO proteins was revealed by immunohistochemistry similar to the spatial distribution of their transcript. In cultured follicles (4 to 8 mm in diameter), the expression levels of SLIT and ROBO members are hormonally regulated by activin A (10 ng/mL) and/or inhibin A (20 ng/mL) after treatment for 24 h. However, the expression of only SLIT2, SLIT3, and ROBO3 mRNA presented a directly opposite response to activin A and inhibin A hormones. These results indicate that SLIT/ROBO pathway is implicated in the prehierarchical follicular development of the hen ovary by an intrafollicular autocrine and/or paracrine action, and is influenced by activin A and inhibin A hormones.

  17. Effect of feeding silages or carrots as supplements to laying hens on production performance, nutrient digestibility, gut structure, gut microflora and feather pecking behaviour.

    Science.gov (United States)

    Steenfeldt, S; Kjaer, J B; Engberg, R M

    2007-08-01

    1. An experiment was carried out to examine the suitability of using maize silage, barley-pea silage and carrots as foraging materials for egg-laying hens. Production performance, nutrient digestibility, gastrointestinal characteristics, including the composition of the intestinal microflora as well as feather pecking behaviour were the outcome variables. 2. The protein content of the foraging material (g/kg DM) was on average 69 g in carrots, 94 g in maize silage and 125 g in barley-pea silage. The starch content was highest in the maize silage (312 g/kg DM), and the content of non-starch polysaccharides (NSP) varied from 196 to 390 g/kg, being lowest in carrots. Sugars were just traceable in the silages, whereas carrots contained on average 496 g/kg DM. 3. Egg production was highest in hens fed either carrots or maize silage, whereas hens fed barley-pea silage produced less (219 vs. 208). Although the consumption of foraging material was high (33, 35 and 48% of the total feed intake on 'as fed' basis for maize silage, barley-pea silage and carrots, respectively) only a minor effect on nitrogen corrected apparent metabolisable energy (AME(n)) and apparent digestibility was seen. At 53 weeks of age, hens fed maize silage had AME(n) and apparent digestibility values close to the control group (12.61 and 12.82, respectively), whereas access to barley-pea silage and carrots resulted in slightly lower values (12.36 and 12.42, respectively). Mortality was reduced dramatically in the three groups given supplements (0.5 to 2.5%) compared to the control group (15.2%). 4. Hens receiving silage had greater relative gizzard weights than the control or carrot-fed groups. At 53 weeks of age, the gizzard-content pH of hens receiving silage was about 0.7 to 0.9 units lower than that of the control or carrot-fed hens. Hens fed both types of silage had higher concentrations of lactic acid (15.6 vs. 3.2 micromoles/g) and acetic acid (3.6 vs. 6.1 micromoles/g) in the gizzard contents

  18. Causes of mortality in laying hens in different housing systems in 2001 to 2004

    Directory of Open Access Journals (Sweden)

    Etterlin Pernille

    2009-01-01

    Full Text Available Abstract Background The husbandry systems for laying hens were changed in Sweden during the years 2001 – 2004, and an increase in the number of submissions for necropsy from laying hen farms was noted. Hence, this study was initiated to compare causes of mortality in different housing systems for commercial laying hens during this change. Methods Based on results from routine necropsies of 914 laying hens performed at the National Veterinary Institute (SVA in Uppsala, Sweden between 2001 and 2004, a retrospective study on the occurrence of diseases and cannibalism, i.e., pecking leading to mortality, in different housing systems was carried out. Using the number of disease outbreaks in caged flocks as the baseline, the expected number of flocks with a certain category of disease in the other housing systems was estimated having regard to the total number of birds in the population. Whether the actual number of flocks significantly exceeded the expected number was determined using a Poisson distribution for the variance of the baseline number, a continuity correction and the exact value for the Poisson distribution function in Excel 2000. Results Common causes of mortality in necropsied laying hens included colibacillosis, erysipelas, coccidiosis, red mite infestation, lymphoid leukosis and cannibalism. Less common diagnoses were Newcastle Disease, pasteurellosis and botulism. Considering the size of the populations in the different housing systems, a larger proportion of laying hens than expected was submitted for necropsy from litter-based systems and free range production compared to hens in cages (P P P Conclusion The results of the present study indicated that during 2001–2004 laying hens housed in litter-based housing systems, with or without access to outdoor areas, were at higher risk of infectious diseases and cannibalistic behaviour compared to laying hens in cages. Future research should focus on finding suitable prophylactic

  19. Behavioural adaptation of laying hens to dilution of diets under mash and pellet form.

    Science.gov (United States)

    Vilariño, M; Picard, M L; Melcion, J P; Faure, J M

    1996-12-01

    1. Two laying diets, control (A) and a low-energy (B) diet diluted by adding 450 g/kg wheat bran, were fed to semi-heavy hens in three different forms: mash, small pellets and large pellets. The behavioural adaptations and the production characteristics for these six regimens were studied on 72 individually caged hens, between 19 and 29 weeks of age, subjected to a lighting pattern of 14 h light/24 h. 2. Diet B, as mash, showed a lower apparent physical density than the others. The hardness and durability of the pelleted diets were similar. 3. Hens fed the mash diet B could not completely adjust their food intake to compensate for the dilution and showed reduced egg output and body weight gain compared to the other groups. 4. Video observation of each hen for 14 consecutive hours showed that mash-fed hens ate for longer periods than pellet-fed hens during the first 11 h (proportion of time spent eating: 41.3% mash B, 32.5% mash A and 20% to 25% for all the pelleted diets). These differences were less pronounced during the last 3 h of the photoperiod. 5. Trough-oriented stereotypies were noted in 14 out of 22 mash-fed hens and in 12 out of 47 pellet-fed hens. Dilution of the diet did not appear to exacerbate stereotyped behaviours under the conditions of the study. 6. This experiment demonstrates that the feeding behaviour of laying hens is affected by the physical characteristics of the diet and that this may lower their productivity. 7. Low-energy pelleted diets might be used to feed hens efficiently in tropical countries where cereal by-products are abundant.

  20. Age-dependent role of steroids in the regulation of growth of the hen follicular wall

    Directory of Open Access Journals (Sweden)

    Lebedev Vladimir A

    2010-02-01

    Full Text Available Abstract Background The ovaries are the primary targets of senescence effects in mammalian and avian species. In the present study, relationships between reproductive aging, sex steroids and the growth pattern of the pre-ovulatory follicle wall were investigated using young hens with long clutch (YLC, old hens with long clutch (OLC, old hens with short clutch (OSC, and old hens with interrupted long clutch (OILC. Methods Experiment 1: Hens were sacrificed 1.5 and 14.5 h after ovulation. Experiment 2: YLC and OILC hens were sacrificed 3.5 h after treatments with LH and/or aminoglutethimide (AG, an inhibitor of steroid synthesis. Volumes of pre-ovulatory follicles (F1-F5 and plasma concentrations of ovarian steroids were determined. Experiment 3: Granulosa and theca cells from F3 follicles of OSC and/or YLC hens were exposed in vitro to estradiol-17beta (E2, testosterone (T and LH and the proliferative activity of the cells was examined using CellTiter 96 Aqueous One Solution Assay. Results In YLC and OLC groups, the total volume of F1-F5 follicles rose between 1.5 and 14.5 h after ovulation (P 2 (P 2 and the follicular volume (P 2 (r = -0.54, P 2 enhanced proliferation of granulosa cells from YLC and OSC groups. The proliferative activity of granulosa and theca cells of YLC hens depended on the interaction between T and LH (P Conclusions These data indicate for the first time that the growth pattern of pre-ovulatory follicles during the ovulatory cycle changes in the course of reproductive aging. E2 seems to play a dual role in this adjustment; it stimulates the growth of the follicular wall in reproductive aged hens, whereas it may inhibit this process in young birds. T and LH are apparently involved in the growth regulation during the pre-ovulatory surge in young hens.

  1. Comparison of bones of 4 strains of laying hens kept in conventional cages and floor pens.

    Science.gov (United States)

    Silversides, F G; Singh, R; Cheng, K M; Korver, D R

    2012-01-01

    The maintenance of bone strength has been an important issue in the debate over cage use for laying hens. Bone strength depends on adequate mechanical load and cages restrict movement. Four laying crosses (Lohmann White, Lohmann Brown, H&N White, and Rhode Island Red × Barred Plymouth Rock cross hens) were housed in conventional cages or in floor pens equipped with perches and nest boxes to measure the effect of the housing system on bone strength. Approximately 15 hens of each genotype from each housing system were killed at 50 wk of age and the radius and tibia of each were removed for analysis. There were no differences between the Lohmann White and H&N White (White Leghorn) hens, likely because of their similar genetic background. The Lohmann Brown and the cross hens (brown-egg layers) were larger and they had heavier bones, but the bone density was not different from that of the other lines. The radius was heavier for hens kept in floor pens than for those kept in cages, but the tibia was not. When hens were kept in floor pens, both bones had greater cortical bone density and cross-sectional area, but the difference between housing systems in cortical bone cross-sectional area was much greater for the radius than it was for the tibia. Although the movement of hens in cages is limited, they spend a great deal of time standing, which puts a mechanical load on the tibia. Hens in floor pens are able to stretch their wings or fly, in contrast to hens kept in cages, which likely explains why the difference between housing systems in cortical bone was greater for the radius than for the tibia.

  2. ANTIGENICITY OF COW'S MILK PROTEINS IN TWO ANIMAL MODELS

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    T.R. Neyestani

    2000-08-01

    Full Text Available Antigenicity of proteins found in cow's milk is age dependent. This is primarily due to infants possessing a more permeable intestinal wall than that in adults. Thus infants may acquire cow's milk allergy during their first year of life. While milk antigen specific IgE may cause allergy in susceptible subjects, there is some evidence indicating that milk antigen specific IgG may play some role in chronic disease development. The puropose of this study was to determine the antigenicity of cow's milk proteins in two animal models and to recommend the more sensitivie one, as an evaluation tool, to assess the antigenicity of a poteintial hypoallergenic formula. A crude extract of cow's milk was injected either to young male rabbits or BALB/C mice in four doses. Pure standard proteins of cow's milk were also injected to separate groups of animals to use their anti sera in later stages. The polyclonal pooled serum was then used to evaluate the antigenicity of the extract by indirect enzyme-linked immunossorbeni assay (LEISA. and Western blotting. Both the rabbit and BALB/C murine mode! demonstrated strong ELISA titres against casein and BSA proteins. However, the rabbit model also had a high antibody response against beta-lactoglobulin (/Mg. The lowest antibody response was found against alpha-kictalbumin («-la in both animal models and no response against immunoglobulins (Igs in either model. In Western blotting, rabbit antiserum showed four bands («-la, /Mg, caseins and BSA compared to two bands (caseins and BSA for mouse antiserum. Considering the allergenicity of these proteins in genetically prone subjects, it may be wise to exclude food sources of caseins as well as major whey proteins (BSA, from the diet of infants with a family history of atopy during the first year of life. The rabbit hyperimmunization model was more sensitive than the murine mode! in detecting antibodies against milk proteins. Thus, the rabbii model should be employed when

  3. Prediction of Local Quality of Protein Structure Models Considering Spatial Neighbors in Graphical Models

    Science.gov (United States)

    Shin, Woong-Hee; Kang, Xuejiao; Zhang, Jian; Kihara, Daisuke

    2017-01-01

    Protein tertiary structure prediction methods have matured in recent years. However, some proteins defy accurate prediction due to factors such as inadequate template structures. While existing model quality assessment methods predict global model quality relatively well, there is substantial room for improvement in local quality assessment, i.e. assessment of the error at each residue position in a model. Local quality is a very important information for practical applications of structure models such as interpreting/designing site-directed mutagenesis of proteins. We have developed a novel local quality assessment method for protein tertiary structure models. The method, named Graph-based Model Quality assessment method (GMQ), explicitly considers the predicted quality of spatially neighboring residues using a graph representation of a query protein structure model. GMQ uses conditional random field as its core of the algorithm, and performs a binary prediction of the quality of each residue in a model, indicating if a residue position is likely to be within an error cutoff or not. The accuracy of GMQ was improved by considering larger graphs to include quality information of more surrounding residues. Moreover, we found that using different edge weights in graphs reflecting different secondary structures further improves the accuracy. GMQ showed competitive performance on a benchmark for quality assessment of structure models from the Critical Assessment of Techniques for Protein Structure Prediction (CASP). PMID:28074879

  4. Animal models of protein allergenicity: potential benefits, pitfalls and challenges.

    Science.gov (United States)

    Dearman, R J; Kimber, I

    2009-04-01

    Food allergy is an important health issue. With an increasing interest in novel foods derived from transgenic crop plants, there is a growing need for the development of approaches suitable for the characterization of the allergenic potential of proteins. There are methods available currently (such as homology searches and serological testing) that are very effective at identifying proteins that are likely to cross-react with known allergens. However, animal models may play a role in the identification of truly novel proteins, such as bacterial or fungal proteins, that have not been experienced previously in the diet. We consider here the potential benefits, pitfalls and challenges of the selection of various animal models, including the mouse, the rat, the dog and the neonatal swine. The advantages and disadvantages of various experimental end-points are discussed, including the measurement of specific IgE by ELISA, Western blotting or functional tests such as the passive cutaneous anaphylaxis assay, and the assessment of challenge-induced clinical symptoms in previously sensitized animals. The experimental variables of route of exposure to test proteins and the incorporation of adjuvant to increase the sensitivity of the responses are considered also. It is important to emphasize that currently none of these approaches has been validated for the purposes of hazard identification in the context of a safety assessment. However, the available evidence suggests that the judicious use of an accurate and robust animal model could provide important additional data that would contribute significantly to the assessment of the potential allergenicity of novel proteins.

  5. Cyclic changes in serum phosphorus of laying hens.

    Science.gov (United States)

    Miller, E R; Harms, R H; Wilson, H R

    1977-03-01

    Three trials were conducted to measure changes in the serum phosphorus level of laying hens over a 24-hour period. Sixty-three-week-old hens were selected for blood sampling according to the criteria that: 1. they laid an egg the day prior to and the day of blood collection and 2. the oviposition time on both days was 10 a.m. +/- 2 hours. Blood samples were obtained via heart puncture. Serum was collected by centrifugation, deproteinized and analyzed colorimetrically for phosphorus content. Sampling times were as follows: Trial 1--6 p.m., 12 midnight, 6 a.m. and 12 noon; Trial 2--6 a.m., 8 a.m., 10 a.m., 12 noon, 2 p.m., 4 p.m. and 6 p.m.; Trial 3--12 midnight, 4 a.m. and 7 a.m. Hens used in this study received natural and/or artifical light from 4:30 a.m. to 7:30 p.m. each day. Results indicated that serum phosphorus reached a peak of 6.08 mg.% at 7 a.m. At 8 a.m., the phosphorus level dropped to 4.88 mg.% and remained within 0.08 mg.% of this value until 12 noon. From 2 p.m. to 6 a.m. it gradually increased from 5.29 mg9% to 5.80 mg.%. Observed changes in serum phosphorus over time are related to changes in shell calcification, bone resorption and remineralization, and renal clearance.

  6. Protein-lipid interactions in bilayer membranes: a lattice model.

    Science.gov (United States)

    Pink, D A; Chapman, D

    1979-04-01

    A lattice model has been developed to study the effects of intrinsic membrane proteins upon the thermodynamic properties of a lipid bilayer membrane. We assume that only nearest-neighbor van der Waals and steric interactions are important and that the polar group interactions can be represented by effective pressure-area terms. Phase diagrams, the temperature T(0), which locates the gel-fluid melting, the transition enthalpy, and correlations were calculated by mean field and cluster approximations. Average lipid chain areas and chain areas when the lipid is in a given protein environment were obtained. Proteins that have a "smooth" homogeneous surface ("cholesterol-like") and those that have inhomogeneous surfaces or that bind lipids specifically were considered. We find that T(0) can vary depending upon the interactions and that another peak can appear upon the shoulder of the main peak which reflects the melting of a eutectic mixture. The transition enthalpy decreases generally, as was found before, but when a second peak appears departures from this behavior reflect aspects of the eutectic mixture. We find that proteins have significant nonzero probabilities for being adjacent to one another so that no unbroken "annulus" of lipid necessarily exists around a protein. If T(0) does not increase much, or decreases, with increasing c, then lipids adjacent to a protein cannot all be all-trans on the time scale (10(-7) sec) of our system. Around a protein the lipid correlation depth is about one lipid layer, and this increases with c. Possible consequences of ignoring changes in polar group interactions due to clustering of proteins are discussed.

  7. Structural Model for the Spider Silk Protein Spidroin-1.

    Science.gov (United States)

    dos Santos-Pinto, José Roberto Aparecido; Arcuri, Helen Andrade; Priewalder, Helga; Salles, Heliana Clara; Palma, Mario Sergio; Lubec, Gert

    2015-09-04

    Most reports about the 3-D structure of spidroin-1 have been proposed for the protein in solid state or for individual domains of these proteins. A gel-based mass spectrometry strategy using collision-induced dissociation (CID) and electron-transfer dissociation (ETD) fragmentation methods was used to completely sequence spidroins-1A and -1B and to assign a series of post-translational modifications (PTMs) on to the spidroin sequences. A total of 15 and 16 phosphorylation sites were detected on spidroin-1A and -1B, respectively. In this work, we present the nearly complete amino acid sequence of spidroin-1A and -1B, including the nonrepetitive N- and C-terminal domains and a highly repetitive central core. We also described a fatty acid layer surrounding the protein fibers and PTMs in the sequences of spidroin-1A and -1B, including phosphorylation. Thus, molecular models for phosphorylated spidroins were proposed in the presence of a mixture fatty acids/water (1:1) and submitted to molecular dynamics simulation. The resulting models presented high content of coils, a higher percentage of α-helix, and an almost neglected content of 310-helix than the previous models. Knowledge of the complete structure of spidroins-1A and -1B would help to explain the mechanical features of silk fibers. The results of the current investigation provide a foundation for biophysical studies of the mechanoelastic properties of web-silk proteins.

  8. Tocopherol and annatto tocotrienols distribution in laying-hen body.

    Science.gov (United States)

    Hansen, H; Wang, T; Dolde, David; Xin, Hongwei

    2015-10-01

    The impact of supplementing laying-hen feed with annatto tocotrienols (T3s) and alpha-tocopherol on the distribution of various forms of vitamin E and cholesterol throughout the hen's body was evaluated. A total of 18 organs or tissues (skin, fat pad, liver and gall bladder, heart, oviduct, forming yolk, laid yolk, lungs, spleen, kidney, pancreas, gizzard, digestive tract, brain, thigh, breast, manure, and blood) were collected after 7 wk of feeding on diets enriched with various levels of alpha-tocopherol and annatto extract that contained gamma-T3 and delta-T3. Tissue weights, contents of lipid, alpha-tocopherol, gamma-T3, delta-T3, cholesterol, and fatty acid composition of extracted lipids from the collected organs and tissues were determined. Tissue weight and lipid content did not change significantly with feed supplementation treatments, except that the liver became heavier with increased levels of supplementation. Overall, the main organs that accumulated the supplemented vitamin E were fat pad, liver and gall bladder, oviduct, forming yolks, laid yolks, kidney, brain, thigh, and breast. Much of annatto gamma-T3 and delta-T3 (> 90%) was found in the manure, indicating poor uptake. In some tissues (brain and oviduct,) a significant increase in polyunsaturated fatty acids was seen with increased supplementation. Alpha-tocopherol impacted the transfer of gamma-T3 to forming and laid yolks, but did not impact delta-T3 transfer. No significant differences were found in most of the tissues in cholesterol, except a reduction in heart, based on tissue as-is. Blood samples showed large variations in individual hens with no significant differences in total and HDL cholesterol, or total triacylglycerols. Supplementing feed with annatto T3s and alpha-tocopherol showed that the vitamin E profile and distribution of the laying-hen body can be altered, but to different extents depending on tissue. The result of this research has significance in enhancing meat nutrient

  9. Evaluation of artificial insemination techniques on fertility in laying hens.

    Science.gov (United States)

    Reinhart, B S; Fiser, P S

    1983-11-01

    The effects of depth of intravaginal insemination of two subsequent semen ejaculates from Rhode Island Red (RIR) and Light Sussex (LS) cockerels on fertility and embryonic mortality of eggs from RIR hens were investigated. Intravaginal insemination to a depth of 3.5 cm resulted in significantly higher fertility than shallow insemination to .5 cm (74.0 vs. 62.3%). Although not statistically significant, fertilizing capacity of first ejaculate of semen collected from either RIR or LS males was greater than the second ejaculate (71.4 vs. 64.9%).

  10. Study of Salmonella Typhimurium infection in laying hens

    Directory of Open Access Journals (Sweden)

    Kapil eChousalkar

    2016-02-01

    Full Text Available Members of Salmonella enterica are frequently involved in egg and egg product related human food poisoning outbreaks worldwide. In Australia, Salmonella Typhimurium is frequently involved in egg and egg product related foodborne illness and Salmonella Mbandaka has also been found to be a contaminant of the layer farm environment. The ability possessed by Salmonella Enteritidis to colonise reproductive organs and contaminate developing eggs has been well described. However, there are few studies investigating this ability for Salmonella Typhimurium. The hypothesis of this study was that the Salmonella Typhimurium can colonise the gut for a prolonged period of time and that horizontal infection through feces is the main route of egg contamination. At 14 weeks of age hens were orally infected with either S. Typhimurium PT 9 or S. Typhimurium PT 9 and Salmonella Mbandaka. Salmonella shedding in feces and eggs was monitored for 15 weeks post infection. Egg shell surface and internal contents of eggs laid by infected hens were cultured independently for detection of Salmonella spp. The mean Salmonella load in feces ranged from 1.54 to 63.35 and 0.31 to 98.38 most probable number/g (MPN/g in the S. Typhimurium and S. Typhimurium + S. Mbandaka group respectively. No correlation was found between mean fecal Salmonella load and frequency of egg shell contamination. Egg shell contamination was higher in S. Typhimurium + S. Mbandaka infected group (7.2% Typhimurium, 14.1% Mbandaka compared to birds infected with S. Typhimurium (5.66% however, co-infection had no significant impact on egg contamination by S. Typhimurium. Throughout the study Salmonella was not recovered from internal contents of eggs laid by hens. Salmonella was isolated from different segments of oviduct of hens from both the groups, however pathology was not observed on microscopic examination. This study investigated Salmonella shedding for up to 15 weeks p.i which is a longer period of

  11. Epithelial structure and function in the hen lower intestine

    DEFF Research Database (Denmark)

    Laverty, G.; Elbrønd, Vibeke Sødring; Árnason, Sigvatur S.

    2006-01-01

    in turn varies inversely with dietary salt content. Numerous studies have shown that following acclimation to low-salt diets, sodium-linked organic substrate co-transporters are largely suppressed, while electrogenic sodium channels (ENaCs) are induced. These changes can be manipulated, at least in part......, by resalination of low-salt hens, or by aldosterone administration to high-salt-acclimated birds. In the coprodeum, the changes in transport are paralleled by extensive remodelling of the mucosal surface, with low-salt acclimation increasing cell numbers, microvillus density and length and the proportion...

  12. Multiscale models and approximation algorithms for protein electrostatics

    CERN Document Server

    Bardhan, Jaydeep P

    2015-01-01

    Electrostatic forces play many important roles in molecular biology, but are hard to model due to the complicated interactions between biomolecules and the surrounding solvent, a fluid composed of water and dissolved ions. Continuum model have been surprisingly successful for simple biological questions, but fail for important problems such as understanding the effects of protein mutations. In this paper we highlight the advantages of boundary-integral methods for these problems, and our use of boundary integrals to design and test more accurate theories. Examples include a multiscale model based on nonlocal continuum theory, and a nonlinear boundary condition that captures atomic-scale effects at biomolecular surfaces.

  13. An Efficient Null Model for Conformational Fluctuations in Proteins

    DEFF Research Database (Denmark)

    Harder, Tim Philipp; Borg, Mikael; Bottaro, Sandro

    2012-01-01

    limited to comparatively short timescales. TYPHON is a probabilistic method to explore the conformational space of proteins under the guidance of a sophisticated probabilistic model of local structure and a given set of restraints that represent nonlocal interactions, such as hydrogen bonds or disulfide...... bridges. The choice of the restraints themselves is heuristic, but the resulting probabilistic model is well-defined and rigorous. Conceptually, TYPHON constitutes a null model of conformational fluctuations under a given set of restraints. We demonstrate that TYPHON can provide information...

  14. Prediction of nuclear proteins using SVM and HMM models

    Directory of Open Access Journals (Sweden)

    Raghava Gajendra PS

    2009-01-01

    Full Text Available Abstract Background The nucleus, a highly organized organelle, plays important role in cellular homeostasis. The nuclear proteins are crucial for chromosomal maintenance/segregation, gene expression, RNA processing/export, and many other processes. Several methods have been developed for predicting the nuclear proteins in the past. The aim of the present study is to develop a new method for predicting nuclear proteins with higher accuracy. Results All modules were trained and tested on a non-redundant dataset and evaluated using five-fold cross-validation technique. Firstly, Support Vector Machines (SVM based modules have been developed using amino acid and dipeptide compositions and achieved a Mathews correlation coefficient (MCC of 0.59 and 0.61 respectively. Secondly, we have developed SVM modules using split amino acid compositions (SAAC and achieved the maximum MCC of 0.66. Thirdly, a hidden Markov model (HMM based module/profile was developed for searching exclusively nuclear and non-nuclear domains in a protein. Finally, a hybrid module was developed by combining SVM module and HMM profile and achieved a MCC of 0.87 with an accuracy of 94.61%. This method performs better than the existing methods when evaluated on blind/independent datasets. Our method estimated 31.51%, 21.89%, 26.31%, 25.72% and 24.95% of the proteins as nuclear proteins in Saccharomyces cerevisiae, Caenorhabditis elegans, Drosophila melanogaster, mouse and human proteomes respectively. Based on the above modules, we have developed a web server NpPred for predicting nuclear proteins http://www.imtech.res.in/raghava/nppred/. Conclusion This study describes a highly accurate method for predicting nuclear proteins. SVM module has been developed for the first time using SAAC for predicting nuclear proteins, where amino acid composition of N-terminus and the remaining protein were computed separately. In addition, our study is a first documentation where exclusively nuclear

  15. A modeling strategy for G-protein coupled receptors

    Directory of Open Access Journals (Sweden)

    Anna Kahler

    2016-03-01

    Full Text Available Cell responses can be triggered via G-protein coupled receptors (GPCRs that interact with small molecules, peptides or proteins and transmit the signal over the membrane via structural changes to activate intracellular pathways. GPCRs are characterized by a rather low sequence similarity and exhibit structural differences even for functionally closely related GPCRs. An accurate structure prediction for GPCRs is therefore not straightforward. We propose a computational approach that relies on the generation of several independent models based on different template structures, which are subsequently refined by molecular dynamics simulations. A comparison of their conformational stability and the agreement with GPCR-typical structural features is then used to select a favorable model. This strategy was applied to predict the structure of the herpesviral chemokine receptor US28 by generating three independent models based on the known structures of the chemokine receptors CXCR1, CXCR4, and CCR5. Model refinement and evaluation suggested that the model based on CCR5 exhibits the most favorable structural properties. In particular, the GPCR-typical structural features, such as a conserved water cluster or conserved non-covalent contacts, are present to a larger extent in the model based on CCR5 compared to the other models. A final model validation based on the recently published US28 crystal structure confirms that the CCR5-based model is the most accurate and exhibits 80.8% correctly modeled residues within the transmembrane helices. The structural agreement between the selected model and the crystal structure suggests that our modeling strategy may also be more generally applicable to other GPCRs of unknown structure.

  16. Illustrating and homology modeling the proteins of the Zika virus

    Science.gov (United States)

    Ekins, Sean; Liebler, John; Neves, Bruno J.; Lewis, Warren G.; Coffee, Megan; Bienstock, Rachelle; Southan, Christopher; Andrade, Carolina H.

    2016-01-01

    The Zika virus (ZIKV) is a flavivirus of the family Flaviviridae, which is similar to dengue virus, yellow fever and West Nile virus. Recent outbreaks in South America, Latin America, the Caribbean and in particular Brazil have led to concern for the spread of the disease and potential to cause Guillain-Barré syndrome and microcephaly. Although ZIKV has been known of for over 60 years there is very little in the way of knowledge of the virus with few publications and no crystal structures. No antivirals have been tested against it either in vitro or in vivo. ZIKV therefore epitomizes a neglected disease. Several suggested steps have been proposed which could be taken to initiate ZIKV antiviral drug discovery using both high throughput screens as well as structure-based design based on homology models for the key proteins. We now describe preliminary homology models created for NS5, FtsJ, NS4B, NS4A, HELICc, DEXDc, peptidase S7, NS2B, NS2A, NS1, E stem, glycoprotein M, propeptide, capsid and glycoprotein E using SWISS-MODEL. Eleven out of 15 models pass our model quality criteria for their further use. While a ZIKV glycoprotein E homology model was initially described in the immature conformation as a trimer, we now describe the mature dimer conformer which allowed the construction of an illustration of the complete virion. By comparing illustrations of ZIKV based on this new homology model and the dengue virus crystal structure we propose potential differences that could be exploited for antiviral and vaccine design. The prediction of sites for glycosylation on this protein may also be useful in this regard. While we await a cryo-EM structure of ZIKV and eventual crystal structures of the individual proteins, these homology models provide the community with a starting point for structure-based design of drugs and vaccines as well as a for computational virtual screening. PMID:27746901

  17. Illustrating and homology modeling the proteins of the Zika virus.

    Science.gov (United States)

    Ekins, Sean; Liebler, John; Neves, Bruno J; Lewis, Warren G; Coffee, Megan; Bienstock, Rachelle; Southan, Christopher; Andrade, Carolina H

    2016-01-01

    The Zika virus (ZIKV) is a flavivirus of the family Flaviviridae, which is similar to dengue virus, yellow fever and West Nile virus. Recent outbreaks in South America, Latin America, the Caribbean and in particular Brazil have led to concern for the spread of the disease and potential to cause Guillain-Barré syndrome and microcephaly. Although ZIKV has been known of for over 60 years there is very little in the way of knowledge of the virus with few publications and no crystal structures. No antivirals have been tested against it either in vitro or in vivo. ZIKV therefore epitomizes a neglected disease. Several suggested steps have been proposed which could be taken to initiate ZIKV antiviral drug discovery using both high throughput screens as well as structure-based design based on homology models for the key proteins. We now describe preliminary homology models created for NS5, FtsJ, NS4B, NS4A, HELICc, DEXDc, peptidase S7, NS2B, NS2A, NS1, E stem, glycoprotein M, propeptide, capsid and glycoprotein E using SWISS-MODEL. Eleven out of 15 models pass our model quality criteria for their further use. While a ZIKV glycoprotein E homology model was initially described in the immature conformation as a trimer, we now describe the mature dimer conformer which allowed the construction of an illustration of the complete virion. By comparing illustrations of ZIKV based on this new homology model and the dengue virus crystal structure we propose potential differences that could be exploited for antiviral and vaccine design. The prediction of sites for glycosylation on this protein may also be useful in this regard. While we await a cryo-EM structure of ZIKV and eventual crystal structures of the individual proteins, these homology models provide the community with a starting point for structure-based design of drugs and vaccines as well as a for computational virtual screening.

  18. Proline is a protein solubilizing solute.

    Science.gov (United States)

    Samuel, D; Kumar, T K; Jayaraman, G; Yang, P W; Yu, C

    1997-02-01

    The effect of proline on the prevention of trichloroacetic acid (TCA)-induced protein precipitation is studied. It is found that proline at high concentrations (> 4.0 M) completely prevents TCA-induced precipitation of hen egg white lysozyme. Other osmolytes such as ethylene glycol, glycerol and sucrose fail to prevent the TCA-induced precipitation of lysozyme. Viscosity and 1-anilino-8-naphthalene sulphonic acid binding experiments suggest that proline at high concentration forms an ordered supramolecular assembly. Proline is shown to increase the solubility of protein due to formation of such higher order assemblies. A model of the supra-molecular assembly of proline is proposed and a possible in vivo role of the increased levels of proline under water stress is discussed.

  19. Modeling regionalized volumetric differences in protein-ligand binding cavities.

    Science.gov (United States)

    Chen, Brian Y; Bandyopadhyay, Soutir

    2012-06-21

    Identifying elements of protein structures that create differences in protein-ligand binding specificity is an essential method for explaining the molecular mechanisms underlying preferential binding. In some cases, influential mechanisms can be visually identified by experts in structural biology, but subtler mechanisms, whose significance may only be apparent from the analysis of many structures, are harder to find. To assist this process, we present a geometric algorithm and two statistical models for identifying significant structural differences in protein-ligand binding cavities. We demonstrate these methods in an analysis of sequentially nonredundant structural representatives of the canonical serine proteases and the enolase superfamily. Here, we observed that statistically significant structural variations identified experimentally established determinants of specificity. We also observed that an analysis of individual regions inside cavities can reveal areas where small differences in shape can correspond to differences in specificity.

  20. Performance of commercial laying hen genotypes on free range and organic farms in Switzerland, France and The Netherlands.

    Science.gov (United States)

    Leenstra, F; Maurer, V; Bestman, M; van Sambeek, F; Zeltner, E; Reuvekamp, B; Galea, F; van Niekerk, T

    2012-01-01

    1. A total of 257 farmers with free ranging laying hens (organic and conventional) in Switzerland, France and The Netherlands with 273 flocks were interviewed to determine the relationships between the genotype of the hens, management conditions and performance. 2. Almost 20 different genotypes (brands) were present on the farms. In France, all birds were brown feathered hens laying brown eggs. In Switzerland and The Netherlands, there were brown, white (white feathered hens laying white eggs) and silver (white feathered hens laying brown eggs) hens. In Switzerland, mixed flocks were also present. 3. The overall effect of system (organic vs. conventional free range) on egg production and mortality was significant, with higher mortality and lower egg production among organic hens. In pair wise comparisons within country, the difference was highly significant in The Netherlands, and showed a non-significant tendency in the same direction in Switzerland and France. 4. White hens tended to perform better than brown hens. Silver hens appeared to have a higher mortality and lower production per hen housed at 60 weeks of age. 5. There were no significant relationships between production, mortality, feather condition and use of outside run or with flock size. 6. There was more variation in mortality and egg production among farms with a small flock size than among farms with a large flock size.

  1. Models of protein and amino acid requirements for cattle

    Directory of Open Access Journals (Sweden)

    Luis Orlindo Tedeschi

    2015-03-01

    Full Text Available Protein supply and requirements by ruminants have been studied for more than a century. These studies led to the accumulation of lots of scientific information about digestion and metabolism of protein by ruminants as well as the characterization of the dietary protein in order to maximize animal performance. During the 1980s and 1990s, when computers became more accessible and powerful, scientists began to conceptualize and develop mathematical nutrition models, and to program them into computers to assist with ration balancing and formulation for domesticated ruminants, specifically dairy and beef cattle. The most commonly known nutrition models developed during this period were the National Research Council (NRC in the United States, Agricultural Research Council (ARC in the United Kingdom, Institut National de la Recherche Agronomique (INRA in France, and the Commonwealth Scientific and Industrial Research Organization (CSIRO in Australia. Others were derivative works from these models with different degrees of modifications in the supply or requirement calculations, and the modeling nature (e.g., static or dynamic, mechanistic, or deterministic. Circa 1990s, most models adopted the metabolizable protein (MP system over the crude protein (CP and digestible CP systems to estimate supply of MP and the factorial system to calculate MP required by the animal. The MP system included two portions of protein (i.e., the rumen-undegraded dietary CP - RUP - and the contributions of microbial CP - MCP as the main sources of MP for the animal. Some models would explicitly account for the impact of dry matter intake (DMI on the MP required for maintenance (MPm; e.g., Cornell Net Carbohydrate and Protein System - CNCPS, the Dutch system - DVE/OEB, while others would simply account for scurf, urinary, metabolic fecal, and endogenous contributions independently of DMI. All models included milk yield and its components in estimating MP required for lactation

  2. Simulation modeling of pooling for combinatorial protein engineering.

    Science.gov (United States)

    Polizzi, Karen M; Spencer, Cody U; Dubey, Anshul; Matsumura, Ichiro; Lee, Jay H; Realff, Matthew J; Bommarius, Andreas S

    2005-12-01

    Pooling in directed-evolution experiments will greatly increase the throughput of screening systems, but important parameters such as the number of good mutants created and the activity level increase of the good mutants will depend highly on the protein being engineered. The authors developed and validated a Monte Carlo simulation model of pooling that allows the testing of various scenarios in silico before starting experimentation. Using a simplified test system of 2 enzymes, betagalactosidase (supermutant, or greatly improved enzyme) and beta-glucuronidase (dud, or enzyme with ancestral level of activity), the model accurately predicted the number of supermutants detected in experiments within a factor of 2. Additional simulations using more complex activity distributions show the versatility of the model. Pooling is most suited to cases such as the directed evolution of new function in a protein, where the background level of activity is minimized, making it easier to detect small increases in activity level. Pooling is most successful when a sensitive assay is employed. Using the model will increase the throughput of screening procedures for directed-evolution experiments and thus lead to speedier engineering of proteins.

  3. Large-Scale Protein-Protein Interactions Detection by Integrating Big Biosensing Data with Computational Model

    Directory of Open Access Journals (Sweden)

    Zhu-Hong You

    2014-01-01

    Full Text Available Protein-protein interactions are the basis of biological functions, and studying these interactions on a molecular level is of crucial importance for understanding the functionality of a living cell. During the past decade, biosensors have emerged as an important tool for the high-throughput identification of proteins and their interactions. However, the high-throughput experimental methods for identifying PPIs are both time-consuming and expensive. On the other hand, high-throughput PPI data are often associated with high false-positive and high false-negative rates. Targeting at these problems, we propose a method for PPI detection by integrating biosensor-based PPI data with a novel computational model. This method was developed based on the algorithm of extreme learning machine combined with a novel representation of protein sequence descriptor. When performed on the large-scale human protein interaction dataset, the proposed method achieved 84.8% prediction accuracy with 84.08% sensitivity at the specificity of 85.53%. We conducted more extensive experiments to compare the proposed method with the state-of-the-art techniques, support vector machine. The achieved results demonstrate that our approach is very promising for detecting new PPIs, and it can be a helpful supplement for biosensor-based PPI data detection.

  4. Helical crystallization on lipid nanotubes: streptavidin as a model protein.

    Science.gov (United States)

    Dang, Thanh X; Farah, Sammy J; Gast, Alice; Robertson, Channing; Carragher, Bridget; Egelman, Edward; Wilson-Kubalek, Elizabeth M

    2005-04-01

    In this study, we use streptavidin (SA) as a model system to study helical protein array formation on lipid nanotubes, an alternative to 2D studies on lipid monolayers. We demonstrate that wild-type and a mutant form of SA form helical arrays on biotinylated lipid nanotubes. 3D maps from helical arrays of wild-type and mutant SA were reconstructed using two different approaches: Fourier-Bessel methods and an iterative single particle algorithm. The maps show that wild-type and mutant streptavidin molecules order differently. The molecular packing arrangements of SA on the surface of the lipid nanotubes differ from previously reported lattice packing of SA on biotinylated monolayers. Helical crystallization on lipid nanotubes presents an alternative platform to explore fundamentals of protein ordering, intermolecular protein interaction and phase behavior. We demonstrate that lipid nanotubes offer a robust and reproducible substrate for forming helical protein arrays which present a means for studying protein structure and structure-function relationships.

  5. Production and purification of avian antibodies (IgYs from inclusion bodies of a recombinant protein central in NAD+ metabolism

    Directory of Open Access Journals (Sweden)

    Paula A. Moreno-González

    2013-08-01

    Full Text Available The use of hens for the production of polyclonal antibodies reduces animal intervention and moreover yields a higher quantity of antibodies than other animal models.  The phylogenetic distance between bird and mammal antigens, often leads to more specific avian antibodies than their mammalian counterparts.Since a large amount of antigen is required for avian antibody production, the use of recombinant proteins for this procedure has been growing faster over the last years. Nevertheless, recombinant protein production through heterologous systems frequently prompts the protein to precipitate, forming insoluble aggregates of limited utility (inclusion bodies. A methodology for the production of avian polyclonal antibodies, using recombinant protein from inclusion bodies is presented in this article.In order to produce the antigen, a recombinant Nicotinamide mononucleotide adenylyltransferase from Giardia intestinalis (His-GiNMNAT was expressed in Escherichia coli.  The protein was purified through solubilization from inclusion bodies prior to its renaturalization.  Antibodies were purified from egg yolk of immunized hens by water dilution, followed by ammonium sulfate precipitation and thiophilic affinity chromatography.The purified antibodies were tested against His-GiNMNAT protein in Western blot essays. From one egg yolk, 14.4 mg of highly pure IgY were obtained; this antibody was able to detect 15ng of His-GiNMNAT.  IgY specificity was improved by means of antigen affinity purification, allowing its use for parasite protein recognition.

  6. A generalized free-solvent model for the osmotic pressure of multi-component solutions containing protein-protein interactions.

    Science.gov (United States)

    McBride, Devin W; Rodgers, V G J

    2014-07-01

    The free-solvent model has been shown to have excellent predictability of the osmotic pressure for single and binary non-interactive proteins in aqueous solutions. Here the free-solvent model is extended to be more generalized by including the contributions of intra- and inter-protein interactions to the osmotic pressure of a solution in the form of homo- and hetero-multimers. The solute-solvent interactions are considered to be unique for each homo- and hetero-multimer in solution. The effect of the various generalized free-solvent model parameters on the osmotic pressure are examined for a single protein solution with a homo-dimer, a binary protein solution with no protein-protein interactions, and a binary protein solution with a hetero-dimer. Finally, the limitations associated with the generalized free-solvent model are discussed.

  7. Relation between social order and use of resources in small and large furnished cages for laying hens.

    Science.gov (United States)

    Shimmura, T; Azuma, T; Hirahara, S; Eguchi, Y; Uetake, K; Tanaka, T

    2008-09-01

    1. The objective was to determine the relation between social rank and use of resources in a small furnished cage with sufficient resources per hen (SF) and a commercial large one with less adequate allowance of facilities per hen (LF). 2. Ninety-two cross layers were used. At the age of 16 weeks, the hens were divided at random into two groups. There were 4 furnished cages with 5 birds per cage and 4 large furnished cages with 18 birds per cage. The dominance hierarchy was determined, in which highest, medium and lowest ranking hens in each cage were identified. Behaviour, use of facilities and physical conditions of these hens were measured (one in each rank category in SF, two in each in LF). 3. Dustbathing and litter scratching were more frequent in the high ranking hens than the medium and low ranked hens in LF, while no significant difference was found between them in SF. 4. No significant difference between SF and LF was found in use of nest boxes. However, pre-laying sitting tended to be less frequent in low ranking than medium and high ranking hens in LF (Social order x Cage design). In the nest box most of time was spent in pre-laying sitting by SF hens, LF high and medium ranked hens (average 94.9%). However, LF low ranking hens spent their time escaping (33.1%), pre-laying sitting (27.7%) standing (25.7%) and moving (13.5%) in the nest. 5. In the large furnished cages with less facilities per hen, high ranking hens may be expected to have priority using the dust bath. In contrast, low ranking hens rarely performed nesting behaviour fully, and spend more time using the nest box as a refuge than for laying.

  8. Folding pathways of a helix-turn-helix model protein

    CERN Document Server

    Hoffmann, D

    1997-01-01

    A small model polypeptide represented in atomic detail is folded using Monte Carlo dynamics. The polypeptide is designed to have a native conformation similar to the central part of the helix-turn-helix protein ROP. Starting from a beta-strand conformation or two different loop conformations of the protein glutamine synthetase, six trajectories are generated using the so-called window move in dihedral angle space. This move changes conformations locally and leads to realistic, quasi-continuously evolving trajectories. Four of the six trajectories end in stable native-like conformations. Their folding pathways show a fast initial development of a helix-bend-helix motif, followed by a dynamic behaviour predicted by the diffusion-collision model of Karplus and Weaver. The phenomenology of the pathways is consistent with experimental results.

  9. MODBASE: a database of annotated comparative protein structure models and associated resources

    OpenAIRE

    Pieper, Ursula; Eswar, Narayanan; Davis, Fred P.; Braberg, Hannes; Madhusudhan, M. S.; Rossi, Andrea; Marti-Renom, Marc; Karchin, Rachel; Webb, Ben M.; Eramian, David; Shen, Min-Yi; Kelly, Libusha; Melo, Francisco; Sali, Andrej

    2005-01-01

    MODBASE () is a database of annotated comparative protein structure models for all available protein sequences that can be matched to at least one known protein structure. The models are calculated by MODPIPE, an automated modeling pipeline that relies on MODELLER for fold assignment, sequence–structure alignment, model building and model assessment (). MODBASE is updated regularly to reflect the growth in protein sequence and structure databases, and improvements in the software for calculat...

  10. Production Performance of White Leghorn Hens Under Different Lighting Regimes

    Directory of Open Access Journals (Sweden)

    Fawwad Ahmad, Ahsan-ul-Haq, M. Ashraf, Jibran Hussain and M. Zubair Siddiqui

    2010-01-01

    Full Text Available A study was conducted for eight weeks to determine the effect of different light sources on the production performance of egg laying birds. For this purpose, 384 single comb White Leghorn layers 40-weeks of age, in their first laying cycle, were obtained from the Poultry Research Centre, University of Agriculture, Faisalabad, Pakistan. The layers were randomly divided into 12 basic experimental units comprising 32 laying hens each, to be designated as replicate. These 12 replicates were further divided into three treatment groups viz; A (fluorescent, B (compact fluorescent, and C (incandescent, each comprising 128 layers. Production performance of birds under different treatments was compared in terms of body weight, feed consumption, egg production, feed conversion ratio, mortality and economics. Hen-day egg production (% was significantly higher (P<0.05 in groups B and C compared to group A. Analysis of data on feed conversion ratio showed that layers in group A and B were significantly less efficient in feed conversion compared to those of group C; difference between the former two groups was non-significant. However, light sources showed non-significant effect on feed consumption, body weight and mortality of the birds. Birds of group B fetched more profit than those of groups A and C.

  11. NUTRIENT DIGESTIBILITY OF THE WASTE OF SACCHARIFICATION PROCESS FROM CASSAVA BAGASSE ON THE LAYING HENS

    Directory of Open Access Journals (Sweden)

    W.M. Ali-Mursyid

    2014-10-01

    Full Text Available The objective of this research was to study the nutrient digestibility and the metabolizable energyvalue of the waste of saccharification process from cassava bagasse (WSPCB on the laying hens.Twenty ISA-Brown laying hens at the age of 72 weeks were randomly distributed into three feedingtreatments which consisted of cassava bagase (CB, WSPCB of solid state fermentation method(WSPCB-SSF, and WSPCB of sub merged fermentation method (WSPCB-SmF. All of the hens werefasted for 24 hours and 15 of them were fed with CB, WSPCB-SSF and WSPCB-SmF (five hens foreach test-diet. The other five hens were still fasted. Then, all of the hens were fasted again and theirexcreta were collected during 48 hours. The nutrient digestibilities which were measured consisted ofthe Apparent and True Digestibility of Dry matter (ADDM and TDDM, Crude Fiber (ADCF andTDCF, Starch (ADS and TDS, and the Apparent and True Metabolizable Energy (AME and TME.The result of this research showed that the saccharification process generated the solid waste with thenutrient digestibility value (ADDM, TDDM, ADS, TDS, AME, and TME which were significantlylower (P<0.05 than those of CB. The crude fiber digestibility value of the WSPCB has an opositephenomenon in which the ADCF and TDCF of WSPCB-SmF were greater than CB. In conclusion, thenutrient digestibility value, except for ADCF and TDCF, of the WSPCB on the laying hens were lowerin value than those CB.

  12. Yolk and albumen corticosterone concentrations in eggs laid by white versus brown caged laying hens.

    Science.gov (United States)

    Navara, K J; Pinson, S E

    2010-07-01

    Maternal stress in birds can have permanent transgenerational effects through the transmission of stress hormones to offspring via the egg yolk. Previous studies have shown that White Leghorn hens show a heightened response to stress compared with Hy-Line Brown hens, producing significantly more corticosterone and displaying longer bouts of tonic immobility after handling, whereas baseline levels of corticosterone are similar between the strains. We tested the hypothesis that higher stress responsiveness would correspond to chronic accumulation and thus higher concentrations of corticosterone in egg yolks after exposure to stressors associated with routine maintenance. Eggs were collected from white and brown hens that were undisturbed except for daily feeding and routine egg collections. Corticosterone was quantified in plasma, egg yolks, and albumen and compared between strains. We predicted that corticosterone concentrations in yolk would be higher in eggs from white versus brown hens but that albumen corticosterone would not differ between strains due to the short term of albumen deposition. As predicted, yolk corticosterone concentrations were significantly higher in eggs produced by white hens, approximately twice those found in eggs laid by brown hens. Plasma and albumen concentrations of corticosterone were similar between groups. These results suggest that offspring hatching from eggs laid by White Leghorn hens are exposed to significantly more corticosterone through concentration in the egg yolk, which could permanently imprint offspring physiology and behavior.

  13. Modelos de regressão aleatória para avaliação da curva de crescimento em matrizes de codorna de corte Random regression models for growth evaluation of meat-type quail hens

    Directory of Open Access Journals (Sweden)

    Bruno Bastos Teixeira

    2012-09-01

    Full Text Available Objetivou-se comparar diferentes modelos de regressão aleatória por meio de funções polinomiais de Legendre de diferentes ordens, para avaliar o que melhor se ajusta ao estudo genético da curva de crescimento de codornas de corte. Foram avaliados dados de 2136 matrizes de codorna de corte, dos quais 1026 pertenciam ao grupo genético UFV1 e 1110 ao grupo UFV2. As codornas foram pesadas nos 1°, 7°, 14°, 21°, 28°, 35°, 42°, 77°, 112° e 147° dias de idade e seus pesos utilizados para a análise. Foram testadas duas possíveis modelagens de variância residual heterogênea, sendo agrupadas em 3 e 5 classes de idade. Após, foi realizado o estudo do modelo de regressão aleatória que melhor aplica-se à curva de crescimento das codornas. A comparação entre os modelos foi feita pelo Critério de Informação de Akaike (AIC, Critério de Informação Bayesiano de Schwarz (BIC, Logaritmo da função de verossimilhança (Log e L e teste da razão de verossimilhança (LRT, ao nível de 1%. O modelo que considerou a heterogeneidade de variância residual CL3 mostrou-se adequado à linhagem UFV1, e o modelo CL5 à linhagem UFV2. Uma função polinomial de Legendre com ordem 5, para efeito genético aditivo direto e 5 para efeito permanente de animal, para a linhagem UFV1 e, com ordem 3, para efeito genético aditivo direto e 5 para efeito permanente de animal para a linhagem UFV2, deve ser utilizada na avaliação genética da curva de crescimento das codornas de corte.The objective was to compare different random regression models using Legendre polynomial functions of different orders, to evaluate what best fits the genetic study of the growth curve of meat quails. It was evaluated data from 2136 cut dies quail, of which 1026 belonged to genetic group UFV1 and 1110 the group UFV2. Quail were weighed at 10, 70, 140, 210, 280, 350, 420, 770, 1120 and 1470 days of age, and weights used for the analysis. It was tested two possible modeling

  14. Effect of dietary nonphytate phosphorus on laying performance and small intestinal epithelial phosphate transporter expression in Dwarf pink-shell laying hens

    Institute of Scientific and Technical Information of China (English)

    Wei Nie; Ying Yang; Jianmin Yuan; Zhong Wang; Yuming Guo

    2014-01-01

    This study examined the effects of various levels of dietary nonphytate phosphorus on laying performance and the expression patterns of phosphorus metabolism related genes in Dwarf pink-shell laying hens. A total of 405 28-week-old Dwarf pink-shell laying hens were fed the same corn-soybean basal meals but containing 0.20%, 0.25%, 0.30%, 0.35%or 0.40%nonphytate phosphorus. The results showed that feed intake, egg production, and average egg weights were quadratically correlated with dietary nonphytate phosphorus content (P<0.05), and the highest egg production, feed intake and average egg weights were achieved when dietary nonphytate phosphorus was at 0.3%(P<0.05). mRNA expression of intestinal sodium phosphorus co-transporter linearly decreased when dietary nonphytate phosphorus increased. mRNA and protein expression of intestinal calbindin and vitamin D receptor correlated quadratically with dietary nonphytate phosphorus, and the highest expression was found when dietary available phosphorus was at 0.25%to 0.3%. In conclusion, the ideal phosphorus requirement for Dwarf pink-shell layer hens is estimated to be 0.3%in a corn-soybean diet. With this level of phosphorus supplementation, calbindin and vitamin D receptor reached their highest expression.

  15. Effects of parenteral gibberellic acid and dietary supplementaion of vitamin D3 on egg quality and physiological characteristics in aged laying hens

    Directory of Open Access Journals (Sweden)

    Waleed M. Razuki

    2014-12-01

    Full Text Available The aim of this study was to determine the effect of parenteral gibberellic acid (GA3 and/or vitamin D3 supplementation in diet on egg quality and blood physiological characteristics in aged laying hens. A total of 270 Lohmann Brown Classic laying hens aging 73-week were randomly assigned to equal three treatment groups (T1, T2 and T3 with equal 3 replicas in each group. The birds of group T1 (control group were injected subcutaneously (SC with sesame oil at 0.2 mL/kg body weight. The birds of group T2 were given with GA3 at 400 µg/kg b.wt., SC, whereas group T3 had diet containing vitamin D3 at 500 IU/kg feed. Relative weight of albumen and egg shell, Haugh unit, shell thickness, serum glucose, serum calcium, serum phosphorous, serum estradiol, and bone calcium absorption were significantly increased in the birds of group T2 and T3. On the other hand, relative weight of yolk, yolk cholesterol, and serum cholesterol were significantly decreased in group T2 and T3 as compared to group T1. However, serum protein and albumen were unaffected in the treatments. In conclusion, the parenteral GA3 and vitamin D3 supplementation in diet could improve egg quality traits and serum blood biochemical perperties in agend laying hens.

  16. Nutritional levels of digestible methionine + cystine to brown-egg laying hens from 50 to 66 weeks of age

    Directory of Open Access Journals (Sweden)

    Clauber Polese

    2012-07-01

    Full Text Available The objective of this study was to determine the requirement of digestible methionine + cystine of brown-eggs laying hens from 50 to 66 weeks age at the end of the first production cycle. The design was completely randomized, with 150 Brown Shaver hens, which were distributed in five treatments with six replications of five birds each. Birds received a basal diet with 2857 kcal/kg metabolizable energy and 15.97% crude protein, supplemented with 0.132; 0.174, 0.215, 0.256 and 0.298% DL-methionine (98%, in order to provide 0.572, 0.613, 0.653, 0.693 and 0.734% digestible methionine + cystine. The levels of digestible methionine + digestible cystine followed, respectively, the relations of 67, 72, 77, 81 and 86% with lysine fixed at 0.851%. Feed intake, methionine + cystine intake, feed conversion per dozen eggs, egg weigth and mass, percentage of egg components, internal egg quality and weight gain were evaluated. Methionine + cystine levels showed a quadratic effect on feed conversion per dozen eggs and egg weight, a linear effect on feed conversion per kilogram of eggs and percentage of albumen. There was also a positive linear effect on yolk percentage. The methionine + cystine requirement was estimated at 0.572%, corresponding to 682 mg of digestible methionine + cystine/bird/day.

  17. ESTIMATION OF BIOCHEMICAL AND HAEMA TOLOGICAL PARAMETERS AFTER TREATMENT WITH BIOVET IN DIFFERENT STRAINS OF LAYING HENS

    Directory of Open Access Journals (Sweden)

    Bashir Mahmood Bhatti, Tanzeela Talat, Rozina Sardar and Ghazala Naheed

    2002-04-01

    Full Text Available This experiment was conducted to study 'effect of Biovet (E.M. Technology on biochemical and haematological parameters of four genetically 'different strains of laying hens including cross, Desj, Fayoumi and Nick Chick. A total of 60 laying hens were involved in the trial giving 15 birds under each strain. Prior to administration of Biovet (2 ml/litre} birds were maintained in,controlled environment for 2 weeks, five blood samples were taken from each strain, and analysed for bichemical and haematological parameters, The same birds were then administered Biovet in drinking water and after 2 weeks of treatment, five blood samples from each strain of chickens were collected and teste4:as was done before treatment. Serum glucose was markedly (P<0.05 increased due to treatment and there was also significant (P<0.05 inter strain variation. Serum protein levels were only affected (P<0.05 due to treatment but there was no inter strain variation, Serum albumin and cholesterol were not affected by treatment, The haematological parameters such as Hb, WBC, Eosinophils, Lymphocytes,PCV , MCH, MCHC; and Heterophils were not affected. by treatment. There was significant (P<0.05 difference in RBCs concentration in serum which also; caused an -increase (P<0.05 in MCV values. The Biovet supplementation presumably stimulated haemopoietic system to improve performance of birds.

  18. EFFECTS OF ENZYMATIC HYDROLYSIS ON THE ANTIOXIDANT ACTIVITY OF WATER- SOLUBLE ELASTIN EXTRACTED FROM BROILER AND SPENT HEN SKIN

    Directory of Open Access Journals (Sweden)

    Mehdi Nadalian

    2015-12-01

    Full Text Available Poultry by-products are great economic sources that need to be exploited. Poultry skin could be utilized to extract protein particularly elastin, which is often incorporated in the production of functional food, cosmetic industry or medicine due to its antioxidative properties. In this study, water-soluble elastin was successfully extracted from broiler and spent hen skin and analysed for antioxidant activities including DPPH (1,1-diphenyl-2-picryl hydrazyl, ABTS and metal chelating activity. Antioxidant activity of elastin extracted from broiler skin hydrolysed by Alcalase (EBA and Elastase (EBE also elastin extracted from spent hen skin hydrolyzed by Alcalase (ESA and Elastease (ESE. The EBE, EBA, ESE and ESA had higher DPPH (16-30, 19-35, 29-48 and 31-50%, respectively, ABTS activity ( 73-79, 60-79, 67-79 and 72-79 %, respectively, and Fe2+chelating activity ( 65-69, 50-56, 71-77 and 62-70 %, respectively. This concluded that water-soluble elastin is a bioactive component that could potentially be used in the formulation of functional foods, nutraceuticals, cosmetic and pharmaceutical industry

  19. Some biochemical parameters of blood plasma of turkey-hens following administration of 1,2,4-triasole derivative.

    Science.gov (United States)

    Krauze, M; Truchliński, J; Cendrowska-Pinkosz, M

    2007-01-01

    The present study involved 180 slaughter turkey-hens of heavy Big-6 type divided into four groups (in triplicate repetition for 15 birds). All the birds were fed with the same standard full-dose mixtures in 5-stage system. The turkey-hens of groups I, II and III were given 1,2,4-triasole derivative (3-(2-pyridil)-4-phenyl-1,2,4-triasole-5-carboxylic acid), which has antibacterial, antifungal and immunomodulating properties, in amount of 50, 75 and 100 microg per 1 dm3 of water. Group IV--control was given water without the additive. The 1,2,4-triasole derivative was given to drinking water, starting from the first day of bird's life and for the whole rearing period. The present results of biochemical analysis of blood plasma showed that addition of examined substance significantly reduced concentration of protein, glucose, triglycerides and uric acid as compared to control. It was stated that tested 1,2,4-triasole derivative elevated the level of HDL fraction percentage and alkaline phosphatase activity in blood plasma.

  20. Use of infrared thermography to assess laying-hen feather coverage.

    Science.gov (United States)

    Zhao, Y; Xin, H; Dong, B

    2013-02-01

    Infrared thermography (IRT) was compared with the traditional 4-scale feather scoring (FS, with 1 representing the worst feather coverage and 4 the best) method for assessing feather coverage of laying hens. The feather coverage of 6 body parts (head, dorsal neck, front neck and crop, back, breast, and belly), body surface temperature distribution, and relative change in sensible heat loss of 60 laying hens (Lohmann SL white breed) at 28, 56, or 73 wk of age (20 hens per age group) were compared by using IRT. For all the 6 body parts and the area-weighted overall, the area of excellent feather (EF) determined by IRT was positively correlated with the 4-scale scores determined by FS (P hens at all body parts. Feather coverage of the hens was classified as 98.7% EF, 1.3% FF, and 0% NF at 28 wk of age; 70.2% EF, 20.6% FF, and 9.2% NF at 56 wk of age; and 35.4% EF, 17.1% FF, and 49.5% NF at 73 wk of age. As a result of less feather coverage and higher surface temperature, sensible heat loss was speculated to be higher for 56- and 73-wk-old hens than for 28-wk-old hens, potentially leading to higher feed-to-egg conversion for the elder hens. It was concluded that IRT is a promising technique or tool that may provide a more objective and quantitative evaluation of laying-hen feather conditions and delineation of bird thermoregulation.

  1. Failed landings after laying hen flight in a commercial aviary over two flock cycles.

    Science.gov (United States)

    Campbell, D L M; Goodwin, S L; Makagon, M M; Swanson, J C; Siegford, J M

    2016-01-01

    Many egg producers are adopting alternative housing systems such as aviaries that provide hens a tiered cage and a litter-covered open floor area. This larger, more complex environment permits expression of behaviors not seen in space-limited cages, such as flight. Flight is an exercise important for strengthening bones; but domestic hens might display imperfect flight landings due to poor flight control. To assess the potential implications of open space, we evaluated the landing success of Lohmann white laying hens in a commercial aviary. Video recordings of hens were taken from 4 aviary sections at peak lay, mid lay and end lay across two flock cycles. Observations were made in each focal section of all flights throughout the day noting flight origin and landing location (outer perch or litter) and landing success or failure. In Flock 1, 9.1% of all flights failed and 21% failed in Flock 2. The number of flights decreased across the laying cycle for both flocks. Proportionally more failed landings were observed in the double row sections in Flock 2. Collisions with other hens were more common than slipping on the ground or colliding with aviary structures across sections and flocks. More hens slipped on the ground and collided with physical structures at peak lay for Flock 2 than at other time points. More collisions with other hens were seen at mid and end lay than at peak lay for Flock 2. Landings ending on perches failed more often than landings on litter. These results indicate potential for flight-related hen injuries in aviary systems resulting from failed landings, which may have implications for hen welfare and optimal system design and management.

  2. Influence of commercial laying hen housing systems on the incidence and identification of Salmonella and Campylobacter.

    Science.gov (United States)

    Jones, D R; Guard, J; Gast, R K; Buhr, R J; Fedorka-Cray, P J; Abdo, Z; Plumblee, J R; Bourassa, D V; Cox, N A; Rigsby, L L; Robison, C I; Regmi, P; Karcher, D M

    2016-05-01

    The housing of laying hens is important for social, industrial, and regulatory aspects. Many studies have compared hen housing systems on the research farm, but few have fully examined commercial housing systems and management strategies. The current study compared hens housed in commercial cage-free aviary, conventional cage, and enriched colony cage systems. Environmental and eggshell pool samples were collected from selected cages/segments of the housing systems throughout the production cycle and monitored for Salmonella and Campylobacter prevalence. At 77 wk of age, 120 hens per housing system were examined for Salmonella and Campylobacter colonization in the: adrenal glands, spleen, ceca, follicles, and upper reproductive tract. All isolates detected from environmental swabs, eggshell pools, and tissues were identified for serotype. Two predominant Salmonella were detected in all samples:S.Braenderup andS.Kentucky.Campylobacter coli and C. jejuni were the only Campylobacter detected in the flocks. Across all housing systems, approximately 7% of hens were colonized with Salmonella, whereas >90% were colonized with Campylobacter Salmonella Braenderup was the isolate most frequently detected in environmental swabs (PCampylobacter jejuni was the isolate most frequently found in environmental swabs (P<0.01), while housing system impacted the prevalence of C. coli and jejuniin ceca (P<0.0001). The results of this study provide a greater understanding of the impact of hen housing systems on hen health and product safety. Additionally, producers and academia can utilize the findings to make informed decisions on hen housing and management strategies to enhance hen health and food safety. Published by Oxford University Press on behalf of Poultry Science Association 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  3. Influence of spermatozoa numbers and insemination frequency on fertility in dwarf broiler breeder hens.

    Science.gov (United States)

    Brillard, J P; McDaniel, G R

    1986-12-01

    The effects of hen age (28 to 31 vs. 49 to 52 weeks of age), sperm concentration (dose used for artificial insemination), and frequency of insemination on fertility and embryonic survival of dwarf broiler breeder hens were examined. Hens in Groups 1 and 2 were inseminated weekly with single doses of either 250 million (Group 1) or 125 million (Group 2) sperm during the 4 weeks of each period. Hens in Groups 3 and 4 were inseminated every other week with duplicate doses on 2 consecutive days, with 250 million sperm/dose in Group 3 and 125 million/dose in Group 4. Hens in Groups 5 and 6 were inseminated weekly with either 250 million (Group 5) or 125 million (Group 6) sperm dose, except the 1st week of each period when they received duplicate doses as in Groups 3 and 4. In Groups 1 and 2, insemination with weekly single doses of semen (250 or 125 million sperm) had no significant effect on fertility of young or old hens. Percent fertility during the 2nd week after artificial insemination was lower in Group 4 than in Group 3 (73.0 vs. 82.9 in young hens and 70.4 vs. 80.7 in old hens). There were no significant differences in fertility between semen doses or age periods in Groups 5 and 6. In these two groups, overall fertility ranged from 94.3 to 95.9%. Complementary studies on individual fertility and embryonic survival showed the beneficial effects of duplicate followed by single inseminations of moderate doses (125 million sperm) practiced at weekly intervals in old hens. This method should be of practical application in commercial practice.

  4. Enantioselective determination of chiral toxaphene congeners in laying hens and eggs using multidimensional high-resolution gas chromatography.

    Science.gov (United States)

    Hamed, Sobhy; Leupold, Guenter; Ismail, Ahmed; Parlar, Harun

    2005-09-07

    A total of 22 chiral toxaphene congeners were analyzed in organ tissues and eggs of laying hens after they had been fed with food spiked with technical toxaphene. For the analysis, multidimensional high-resolution gas chromatography using a chiral column coated with randomly silylated heptakis(O-tert-butyldimethylsilyl)-beta-cyclodextrin, electron capture detection, and valveless "live column switching" technique was applied. The analytical results were additionally confirmed with mass spectral data, recorded in electron-capture negative ionization mode with selected-ion monitoring mass spectrometry. During both the feeding period of the laying hens with toxaphene-contaminated food (38 weeks, accumulation phase) and the following subsiding period without toxaphenes (another 14 weeks, decontamination phase), organs (liver, kidney, skin/fat), blood, meat, and eggs of the hens served as model matrices for toxaphene uptake. The enantiomeric ratios (ERs) of congeners 26, 31, 32, 40, 41, 42(a+b), 44, 50, and 62--known as the most important components of technical toxaphene occurring in the environment--could be analytically determined. Significant differences were observed with respect to their initial racemic ratios. On the basis of their chemical structures, the metabolic pathways of some congeners could be explained. Astonishingly, some of the toxaphenes applied as racemates could merely be found as single enantiomers at the end of the feeding program, for example, congener 32 in blood and meat samples or congener 44, especially in organ tissues, which showed ERs of zero or infinity. The findings of this study impressively emphasize that it is essential to isolate and analyze individual toxaphene enantiomers in food and biota tissues to be capable of evaluating their toxicity and metabolization more specifically.

  5. Digestible tryptophan:digestible lysine ratio in diets for laying hens from 24 to 40 weeks of age

    Directory of Open Access Journals (Sweden)

    Arele Arlindo Calderano

    2012-10-01

    Full Text Available The objective of this study was to determine the ideal digestible tryptophan:digestible lysine ratio in diets for laying hens from 24 to 40 weeks of age. Two hundred and forty Hy-Line W-36 laying hens at 24 weeks of age were distributed in a completely randomized design, with five treatments, eight replicates and six birds per experimental unit. The digestible tryptophan levels in the experimental diets were 1.57; 1.68; 1.79; 1.90 and 2.01 g/kg, providing ratios of digestible tryptophan:digestible lysine of 0.215; 0.230; 0.245; 0.260 and 0.275. The increase in the levels of digestible tryptophan in the diet linearly improved the feed intake, digestible tryptophan intake, digestible lysine intake, egg production, egg mass, feed conversion per egg mass and utilization efficiency of digestible lysine for eggs mass. There were quadratic effects from the digestible tryptophan levels on egg weight. For the efficiency of utilization of digestible lysine for egg mass, there was better adjustment of the data to the LRP model. The level of digestible tryptophan in the diet from which the plateau occurred was 0.184%. This level corresponded to the intake of 142 mg/bird/day of digestible tryptophan and digestible tryptophan:digestible lysine ratio of 0.252. The ideal digestible tryptophan:digestible lysine ratio recommended in diets for laying hens from 24 to 40 weeks of age is 0.252 (25.2%.

  6. A simple quantitative model of macromolecular crowding effects on protein folding: Application to the murine prion protein(121-231)

    Science.gov (United States)

    Bergasa-Caceres, Fernando; Rabitz, Herschel A.

    2013-06-01

    A model of protein folding kinetics is applied to study the effects of macromolecular crowding on protein folding rate and stability. Macromolecular crowding is found to promote a decrease of the entropic cost of folding of proteins that produces an increase of both the stability and the folding rate. The acceleration of the folding rate due to macromolecular crowding is shown to be a topology-dependent effect. The model is applied to the folding dynamics of the murine prion protein (121-231). The differential effect of macromolecular crowding as a function of protein topology suffices to make non-native configurations relatively more accessible.

  7. The effectiveness of Aloe vera barbadensis bioactives on laying hens on commercial farmers

    OpenAIRE

    Tiurma Pasaribu; A.P Sinurat; T Purwadaria

    2006-01-01

    A field trial was conducted to study the effectiveness of dry gel Aloe vera (DG) as a feed additive for laying hens in commercial farms. The trial was consisted of two treatments, one was control, commonly used farmer ration containing antibiotic of zinc bacitracin at 0.5 g/kg and the second feed containing DG equal to 1.0 g/kg. Every treatment had two replicates with 504 Loghman laying hens. The hen day production (% HD), egg weight, feed consumption, feed conversion ratio (FCR), egg quality...

  8. Pathomorphological changes in the small intestine of hens at the egg drop syndrome

    OpenAIRE

    BORISEVICH B.; SHATSILO E.; YUSHKOVA I.

    2013-01-01

    Pathomorphological research of dead bodies of hens with the egg drop syndrome is conducted. It is set that in 17,57 % hens diarrhea is registered. During the dissection at these hens the serosal catarrh of small intestine is set. At the histological examination microscopic changes are registered in all layers of intestinal wall, except for her serosa. Basic microscopic changes there was in a mucous shall. On most areas of between her folds a mucous shall is fully blasted to the area of crypts...

  9. Assessment of lighting needs by W-36 laying hens via preference test.

    Science.gov (United States)

    Ma, H; Xin, H; Zhao, Y; Li, B; Shepherd, T A; Alvarez, I

    2016-04-01

    Light intensity, spectrum and pattern may affect laying hen behaviors and production performance. However, requirements of these lighting parameters from the hens' standpoint are not fully understood. This study was conducted to investigate hens' needs for light intensity and circadian rhythm using a light tunnel with five identical compartments each at a different fluorescent light intensity of tested each time, and six groups or replicates were conducted. Behaviors of the hens were continuously recorded, yielding data on daily time spent, daily feed intake, daily feeding time, and eggs laid under each light intensity and daily inter-compartment movement. The results show that the hens generally spent more time in lower light intensities. Specifically, the hens spent 6.4 h (45.4%) at 5 lux, 3.0 h (22.1%) at 15 lux, 3.1 h (22.2%) at 30 lux and 1.5 h (10.3%) at 100 lux under light condition; and an accumulation of 10.0 h in darkness (light-dark rhythm differs from the typical commercial practice of providing continuous dark period for certain part of the day (e.g. 8 h at night). Distributions of daily feed intake (87.3 g/hen) among the different light conditions mirrored the trend of time spent in the respective light intensity, that is, highest at 5 lux (28.4 g/hen, 32.5% daily total) and lowest at 100 lux (5.8 g/hen, 6.7%). Hen-day egg production rate was 96.0%. Most of the eggs were laid in <1 lux (61.9% of total) which was significantly higher than under other light intensities (P<0.05). Findings from this study offer insights into preference of fluorescent light intensity by the laying hens. Further studies to assess or verify welfare and performance responses of the hens to the preferred lighting conditions and rhythm over extended periods are recommended.

  10. Transgenic rabbits as therapeutic protein bioreactors and human disease models.

    Science.gov (United States)

    Fan, Jianglin; Watanabe, Teruo

    2003-09-01

    Genetically modified laboratory animals provide a powerful approach for studying gene expression and regulation and allow one to directly examine structure-function and cause-and-effect relationships in pathophysiological processes. Today, transgenic mice are available as a research tool in almost every research institution. On the other hand, the development of a relatively large mammalian transgenic model, transgenic rabbits, has provided unprecedented opportunities for investigators to study the mechanisms of human diseases and has also provided an alternative way to produce therapeutic proteins to treat human diseases. Transgenic rabbits expressing human genes have been used as a model for cardiovascular disease, AIDS, and cancer research. The recombinant proteins can be produced from the milk of transgenic rabbits not only at lower cost but also on a relatively large scale. One of the most promising and attractive recombinant proteins derived from transgenic rabbit milk, human alpha-glucosidase, has been successfully used to treat the patients who are genetically deficient in this enzyme. Although the pronuclear microinjection is still the major and most popular method for the creation of transgenic rabbits, recent progress in gene targeting and animal cloning has opened new avenues that should make it possible to produce transgenic rabbits by somatic cell nuclear transfer in the future. Based on a computer-assisted search of the studies of transgenic rabbits published in the English literature here, we introduce to the reader the achievements made thus far with transgenic rabbits, with emphasis on the application of these rabbits as human disease models and live bioreactors for producing human therapeutic proteins and on the recent progress in cloned rabbits.

  11. Models to predict intestinal absorption of therapeutic peptides and proteins.

    Science.gov (United States)

    Antunes, Filipa; Andrade, Fernanda; Ferreira, Domingos; Nielsen, Hanne Morck; Sarmento, Bruno

    2013-01-01

    Prediction of human intestinal absorption is a major goal in the design, optimization, and selection of drugs intended for oral delivery, in particular proteins, which possess intrinsic poor transport across intestinal epithelium. There are various techniques currently employed to evaluate the extension of protein absorption in the different phases of drug discovery and development. Screening protocols to evaluate protein absorption include a range of preclinical methodologies like in silico, in vitro, in situ, ex vivo and in vivo. It is the careful and critical use of these techniques that can help to identify drug candidates, which most probably will be well absorbed from the human intestinal tract. It is well recognized that the human intestinal permeability cannot be accurately predicted based on a single preclinical method. However, the present social and scientific concerns about the animal well care as well as the pharmaceutical industries need for rapid, cheap and reliable models predicting bioavailability give reasons for using methods providing an appropriate correlation between results of in vivo and in vitro drug absorption. The aim of this review is to describe and compare in silico, in vitro, in situ, ex vivo and in vivo methods used to predict human intestinal absorption, giving a special attention to the intestinal absorption of therapeutic peptides and proteins.

  12. Programas de alimentação para matrizes pesadas após o pico de postura, com base em modelos para predizer a exigência energética Feeding programs for broiler breeder hens after peak production based on models to predict energy requirements

    Directory of Open Access Journals (Sweden)

    Nilva Kazue Sakomura

    2004-10-01

    Full Text Available Este trabalho foi conduzido com o objetivo de avaliar o desempenho de matrizes pesadas, submetidas a diferentes programas de alimentação estabelecidos pela aplicação de modelos para predizer as exigências energéticas, após o pico de postura. O experimento foi conduzido no setor de avicultura da UNESP Campus Jaboticabal, com duração de 84 dias (três períodos de 28 dias. Foram utilizadas 740 matrizes de corte Hubbard Hy-Yield e 80 machos Petterson, com 55 semanas de idade. O delineamento foi inteiramente casualizado, com quatro tratamentos e cinco repetições de 37 aves por repetição (box e um modelo fatorial 4´3 (quatro tratamentos ´ três períodos. Os programas de alimentação avaliados foram: T1 - Fornecimento de ração de acordo com o padrão da linhagem (428 kcal/ave/dia de 55 a 66 semanas de idade; T2 - Redução semanal de energia (2 kcal de EM/ave em cada semana; T3 - Fornecimento de ração de acordo com o modelo de exigência de EM, UNESP (2000; e T4 - Fornecimento de ração de acordo com o modelo, NRC (1994. O programa de alimentação com redução semanal de energia foi adequado para manter os desempenhos produtivo e reprodutivo das aves, indicando a possibilidade de redução de 2 kcal/ave/dia, em cada semana, na alimentação de matrizes pesadas após 55 semanas de idade. Os modelos UNESP e NRC proporcionaram estimativas mais elevadas das exigências energéticas que o modelo padrão, provavelmente em decorrência do ganho de peso das matrizes, que esteve acima do recomendado para a linhagem, promovendo maiores exigências de energia para mantença.This research was carried out to evaluate the performance of broiler breeder hens submitted to different feeding programs applying models to predict the metabolizable energy requirements after peak production. The experiment was conducted during 84 days (three periods of 28 days, at the Sao Paulo State University - Jaboticabal. Seven hundred and forty female broiler

  13. Insights on protein-DNA recognition by coarse grain modelling

    Science.gov (United States)

    Poulain, Pierre; Saladin, Adrien; Hartmann, Brigitte; Prévost, Chantal

    2008-01-01

    Coarse grain modelling of macromolecules is a new approach potentially well adapted to answer numerous issues, ranging from physics to biology. We propose here an original DNA coarse grain model specifically dedicated to protein–DNA docking, a crucial, but still largely unresolved, question in molecular biology. Using a representative set of protein–DNA complexes, we first show that our model is able to predict the interaction surface between the macromolecular partners taken in their bound form. In a second part, the impact of the DNA sequence and electrostatics, together with the DNA and protein conformations on docking is investigated. Our results strongly suggest that the overall DNA structure mainly contributes in discriminating the interaction site on cognate proteins. Direct electrostatic interactions between phosphate groups and amino acids side chains strengthen the binding. Overall, this work demonstrates that coarse grain modelling can reveal itself a precious auxiliary for a general and complete description and understanding of protein–DNA association mechanisms. PMID:18478582

  14. Multiscale modeling and simulation of microtubule–motor-protein assemblies

    Science.gov (United States)

    Gao, Tong; Blackwell, Robert; Glaser, Matthew A.; Betterton, M. D.; Shelley, Michael J.

    2016-01-01

    Microtubules and motor proteins self-organize into biologically important assemblies including the mitotic spindle and the centrosomal microtubule array. Outside of cells, microtubule-motor mixtures can form novel active liquid-crystalline materials driven out of equilibrium by adenosine triphosphate–consuming motor proteins. Microscopic motor activity causes polarity-dependent interactions between motor proteins and microtubules, but how these interactions yield larger-scale dynamical behavior such as complex flows and defect dynamics is not well understood. We develop a multiscale theory for microtubule-motor systems in which Brownian dynamics simulations of polar microtubules driven by motors are used to study microscopic organization and stresses created by motor-mediated microtubule interactions. We identify polarity-sorting and crosslink tether relaxation as two polar-specific sources of active destabilizing stress. We then develop a continuum Doi-Onsager model that captures polarity sorting and the hydrodynamic flows generated by these polar-specific active stresses. In simulations of active nematic flows on immersed surfaces, the active stresses drive turbulent flow dynamics and continuous generation and annihilation of disclination defects. The dynamics follow from two instabilities, and accounting for the immersed nature of the experiment yields unambiguous characteristic length and time scales. When turning off the hydrodynamics in the Doi-Onsager model, we capture formation of polar lanes as observed in the Brownian dynamics simulation. PMID:26764729

  15. Relative Binding Free Energy Calculations Applied to Protein Homology Models.

    Science.gov (United States)

    Cappel, Daniel; Hall, Michelle Lynn; Lenselink, Eelke B; Beuming, Thijs; Qi, Jun; Bradner, James; Sherman, Woody

    2016-12-27

    A significant challenge and potential high-value application of computer-aided drug design is the accurate prediction of protein-ligand binding affinities. Free energy perturbation (FEP) using molecular dynamics (MD) sampling is among the most suitable approaches to achieve accurate binding free energy predictions, due to the rigorous statistical framework of the methodology, correct representation of the energetics, and thorough treatment of the important degrees of freedom in the system (including explicit waters). Recent advances in sampling methods and force fields coupled with vast increases in computational resources have made FEP a viable technology to drive hit-to-lead and lead optimization, allowing for more efficient cycles of medicinal chemistry and the possibility to explore much larger chemical spaces. However, previous FEP applications have focused on systems with high-resolution crystal structures of the target as starting points-something that is not always available in drug discovery projects. As such, the ability to apply FEP on homology models would greatly expand the domain of applicability of FEP in drug discovery. In this work we apply a particular implementation of FEP, called FEP+, on congeneric ligand series binding to four diverse targets: a kinase (Tyk2), an epigenetic bromodomain (BRD4), a transmembrane GPCR (A2A), and a protein-protein interaction interface (BCL-2 family protein MCL-1). We apply FEP+ using both crystal structures and homology models as starting points and find that the performance using homology models is generally on a par with the results when using crystal structures. The robustness of the calculations to structural variations in the input models can likely be attributed to the conformational sampling in the molecular dynamics simulations, which allows the modeled receptor to adapt to the "real" conformation for each ligand in the series. This work exemplifies the advantages of using all-atom simulation methods with

  16. Evaluation of Salmonella enterica serovar Enteritidis pathogenicity island-1 proteins as vaccine candidates against S. Enteritidis challenge in chickens.

    Science.gov (United States)

    Desin, Taseen S; Wisner, Amanda L S; Lam, Po-King S; Berberov, Emil; Mickael, Claudia S; Potter, Andrew A; Köster, Wolfgang

    2011-03-24

    Salmonella enterica serovar Enteritidis (S. Enteritidis) is a major cause of gastrointestinal disease in humans worldwide, which mainly results from the consumption of contaminated poultry meat and eggs. Vaccination of chickens is an important strategy to lower the prevalence of Salmonella in poultry flocks. The S. Enteritidis type 3 secretion system (T3SS) encoded on Salmonella pathogenicity island-1 (SPI-1) is an important virulence factor that plays a role in invasion and systemic spread in chickens. In this manuscript, we evaluated the efficacy of SPI-1 proteins as vaccine candidates for protection against S. Enteritidis oral challenge. Our results demonstrate for the first time that SPI-1 T3SS proteins elicit antigen specific IgG antibody responses in chickens. In one study we show that vaccination with the aforementioned proteins reduces the levels of S. Enteritidis in the liver, but not in the spleen and cecal contents of chickens. However, a second study shows that vaccination of hens with SPI-1 proteins using a seeder model of infection does not affect the levels of S. Enteritidis in the cecal contents or internal organs of progeny obtained from these hens. Hence, the SPI-1 proteins, in conjunction with other proteins, may form important components of subunit vaccines used for protection against colonization by S. Enteritidis in poultry.

  17. Benchmarking consensus model quality assessment for protein fold recognition

    Directory of Open Access Journals (Sweden)

    McGuffin Liam J

    2007-09-01

    Full Text Available Abstract Background Selecting the highest quality 3D model of a protein structure from a number of alternatives remains an important challenge in the field of structural bioinformatics. Many Model Quality Assessment Programs (MQAPs have been developed which adopt various strategies in order to tackle this problem, ranging from the so called "true" MQAPs capable of producing a single energy score based on a single model, to methods which rely on structural comparisons of multiple models or additional information from meta-servers. However, it is clear that no current method can separate the highest accuracy models from the lowest consistently. In this paper, a number of the top performing MQAP methods are benchmarked in the context of the potential value that they add to protein fold recognition. Two novel methods are also described: ModSSEA, which based on the alignment of predicted secondary structure elements and ModFOLD which combines several true MQAP methods using an artificial neural network. Results The ModSSEA method is found to be an effective model quality assessment program for ranking multiple models from many servers, however further accuracy can be gained by using the consensus approach of ModFOLD. The ModFOLD method is shown to significantly outperform the true MQAPs tested and is competitive with methods which make use of clustering or additional information from multiple servers. Several of the true MQAPs are also shown to add value to most individual fold recognition servers by improving model selection, when applied as a post filter in order to re-rank models. Conclusion MQAPs should be benchmarked appropriately for the practical context in which they are intended to be used. Clustering based methods are the top performing MQAPs where many models are available from many servers; however, they often do not add value to individual fold recognition servers when limited models are available. Conversely, the true MQAP methods

  18. Effects of ovariectomy or force feeding on the plasma concentrations of prolactin and luteinizing hormone in incubating turkey hens.

    Science.gov (United States)

    Zadworny, D; Etches, R J

    1987-02-01

    The effect of ovariectomy (OVX) on plasma concentrations of prolactin (PRL) and luteinizing hormone (LH) in incubating turkey hens was studied. Neither the sham-operated nor the OVX hens exhibited any change in the pattern of incubation behavior as a result of the surgery. Plasma concentrations of estradiol decreased to less than approximately 3 pg/ml by 2 days after surgery in the OVX hens. There were no significant differences in plasma levels of PRL between the sham-operated and OVX hens throughout the study. The concentration of PRL did not change in either the sham-operated or OVX hens and was maintained at high levels after surgery and during incubation of the eggs. By 2 days after hens were placed into cages, plasma levels of PRL significantly decreased and were maintained at low levels in both groups. The concentration of LH did not change in either group during the two wk after surgery when the hens were incubating eggs. After the hens were placed into cages, the concentration of LH increased in the OVX hens and was maintained at significantly higher levels than in the sham-operated hens. By contrast, the concentration of LH increased within 4 days after OVX of out-of-lay but nonincubating hens. The delay in the postcastration increase in plasma level of LH in the OVX hens was not associated with anorexia of incubating hens, since plasma levels of LH were not affected by force-feeding unless plasma levels of PRI were suppressed by nest deprivation.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. The distribution of carotenoids in hens fed on biofortified maize is influenced by feed composition, absorption, resource allocation and storage.

    Science.gov (United States)

    Moreno, Jose Antonio; Díaz-Gómez, Joana; Nogareda, Carmina; Angulo, Eduardo; Sandmann, Gerhard; Portero-Otin, Manuel; Serrano, José C E; Twyman, Richard M; Capell, Teresa; Zhu, Changfu; Christou, Paul

    2016-10-14

    Carotenoids are important dietary nutrients with health-promoting effects. The biofortification of staple foods with carotenoids provides an efficient delivery strategy but little is known about the fate and distribution of carotenoids supplied in this manner. The chicken provides a good model of human carotenoid metabolism so we supplemented the diets of laying hens using two biofortified maize varieties with distinct carotenoid profiles and compared the fate of the different carotenoids in terms of distribution in the feed, the hen's livers and the eggs. We found that after a period of depletion, pro-vitamin A (PVA) carotenoids were preferentially diverted to the liver and relatively depleted in the eggs, whereas other carotenoids were transported to the eggs even when the liver remained depleted. When retinol was included in the diet, it accumulated more in the eggs than the livers, whereas PVA carotenoids showed the opposite profile. Our data suggest that a transport nexus from the intestinal lumen to the eggs introduces bottlenecks that cause chemically-distinct classes of carotenoids to be partitioned in different ways. This nexus model will allow us to optimize animal feed and human diets to ensure that the health benefits of carotenoids are delivered in the most effective manner.

  20. Modelling proteins' hidden conformations to predict antibiotic resistance

    Science.gov (United States)

    Hart, Kathryn M.; Ho, Chris M. W.; Dutta, Supratik; Gross, Michael L.; Bowman, Gregory R.

    2016-10-01

    TEM β-lactamase confers bacteria with resistance to many antibiotics and rapidly evolves activity against new drugs. However, functional changes are not easily explained by differences in crystal structures. We employ Markov state models to identify hidden conformations and explore their role in determining TEM's specificity. We integrate these models with existing drug-design tools to create a new technique, called Boltzmann docking, which better predicts TEM specificity by accounting for conformational heterogeneity. Using our MSMs, we identify hidden states whose populations correlate with activity against cefotaxime. To experimentally detect our predicted hidden states, we use rapid mass spectrometric footprinting and confirm our models' prediction that increased cefotaxime activity correlates with reduced Ω-loop flexibility. Finally, we design novel variants to stabilize the hidden cefotaximase states, and find their populations predict activity against cefotaxime in vitro and in vivo. Therefore, we expect this framework to have numerous applications in drug and protein design.

  1. Factors influencing protein tyrosine nitration--structure-based predictive models.

    Science.gov (United States)

    Bayden, Alexander S; Yakovlev, Vasily A; Graves, Paul R; Mikkelsen, Ross B; Kellogg, Glen E

    2011-03-15

    Models for exploring tyrosine nitration in proteins have been created based on 3D structural features of 20 proteins for which high-resolution X-ray crystallographic or NMR data are available and for which nitration of 35 total tyrosines has been experimentally proven under oxidative stress. Factors suggested in previous work to enhance nitration were examined with quantitative structural descriptors. The role of neighboring acidic and basic residues is complex: for the majority of tyrosines that are nitrated the distance to the heteroatom of the closest charged side chain corresponds to the distance needed for suspected nitrating species to form hydrogen bond bridges between the tyrosine and that charged amino acid. This suggests that such bridges play a very important role in tyrosine nitration. Nitration is generally hindered for tyrosines that are buried and for those tyrosines for which there is insufficient space for the nitro group. For in vitro nitration, closed environments with nearby heteroatoms or unsaturated centers that can stabilize radicals are somewhat favored. Four quantitative structure-based models, depending on the conditions of nitration, have been developed for predicting site-specific tyrosine nitration. The best model, relevant for both in vitro and in vivo cases, predicts 30 of 35 tyrosine nitrations (positive predictive value) and has a sensitivity of 60/71 (11 false positives). Copyright © 2010 Elsevier Inc. All rights reserved.

  2. Enzymatic hydrolysis of protein:mechanism and kinetic model

    Institute of Scientific and Technical Information of China (English)

    Qi Wei; He Zhimin

    2006-01-01

    The bioreaction mechanism and kinetic behavior of protein enzymatic hydrolysis for preparing active peptides were investigated to model and characterize the enzymatic hydrolysis curves.Taking into account single-substrate hydrolysis,enzyme inactivation and substrate or product inhibition,the reaction mechanism could be deduced from a series of experimental results carried out in a stirred tank reactor at different substrate concentrations,enzyme concentrations and temperatures based on M-M equation.An exponential equation dh/dt = aexp(-bh) was also established,where parameters a and b have different expressions according to different reaction mechanisms,and different values for different reaction systems.For BSA-trypsin model system,the regressive results agree with the experimental data,i.e.the average relative error was only 4.73%,and the reaction constants were determined as Km = 0.0748 g/L,Ks = 7.961 g/L,kd = 9.358/min,k2 =38.439/min,Ea= 64.826 kJ/mol,Ed= 80.031 kJ/mol in accordance with the proposed kinetic mode.The whole set of exponential kinetic equations can be used to model the bioreaction process of protein enzymatic hydrolysis,to calculate the thermodynamic and kinetic constants,and to optimize the operating parameters for bioreactor design.

  3. Pathogenicity and distribution of egg-drop syndrome-1976 virus (JPA-1) in inoculated laying hens.

    Science.gov (United States)

    Yamaguchi, S; Imada, T; Kawamura, H; Taniguchi, T; Kawakami, M

    1981-01-01

    Rhode Island Red laying hens that lacked hemagglutination-inhibition antibody were inoculated orally with the JPA-1 strain of adenovirus isolated from a flock affected with egg-drop syndrome-1976 in Japan and observed for 80 days. Inoculated hens laid abnormal eggs, such as shell-less, soft-shelled, and cracked eggs and those with loss of pigmentation, from 8 days postinoculation (PI). Fifteen out of 16 hens laid abnormal eggs. Egg-production rte fell from 94% to 50% between 13 and 16 days PI. When the abnormal eggs were excluded, egg production was 17%; then it recoverd slowly, reaching 67% by the end of the experiment. The virus was recovered from various organs of inoculated hens from 3 to 7 days PI. Fluorescent antigens of the virus were observed in the epithelial cells and desquamated cells from the epithelium of the uterus and isthmus 10 and 14 days PI.

  4. Validation of an automated mite counter for Dermanyssus gallinae in experimental laying hen cages.

    Science.gov (United States)

    Mul, Monique F; van Riel, Johan W; Meerburg, Bastiaan G; Dicke, Marcel; George, David R; Groot Koerkamp, Peter W G

    2015-08-01

    For integrated pest management (IPM) programs to be maximally effective, monitoring of the growth and decline of the pest populations is essential. Here, we present the validation results of a new automated monitoring device for the poultry red mite (Dermanyssus gallinae), a serious pest in laying hen facilities world-wide. This monitoring device (called an "automated mite counter") was validated in experimental laying hen cages with live birds and a growing population of D. gallinae. This validation study resulted in 17 data points of 'number of mites counted' by the automated mite counter and the 'number of mites present' in the experimental laying hen cages. The study demonstrated that the automated mite counter was able to track the D. gallinae population effectively. A wider evaluation showed that this automated mite counter can become a useful tool in IPM of D. gallinae in laying hen facilities.

  5. Development with age of nest box use and gregarious nesting in laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch

    2010-01-01

    Use of nest boxes is an important part of the behavioural repertoire of laying hens kept under commercial conditions. A special form of nest box use is gregarious nesting, which occurs when a hen given the choice between an occupied and an unoccupied nest site chooses the occupied nest site...... experiences in selection of nest locations, causing the found decrease in frequency of gregarious nesting after age 20 weeks. A general preference for corner and end nest boxes is suggested to have triggered the initial use of the left nest box by the first hens coming into lay and to have maintained...... risk of broken or dirty eggs. The main objectives were to investigate the use of nest boxes according to their position and the occurrence of gregarious nesting with age. Twelve groups of 15 Isa Warren hens were housed in pens each containing three adjacent roll-out nest boxes only differing...

  6. Long term selection for reduced or increased pecking behaviour in laying hens

    DEFF Research Database (Denmark)

    Buitenhuis, A J; Kjaer, J B

    2008-01-01

    Feather pecking in laying hens is an important issue in animal welfare. Four studies in laying hens were selected which investigated increased or reduced pecking behaviour using direct or indirect measures of feather pecking behaviour. Direct comparison of the selected experiments is difficult...... selection for reduced pecking behaviour changes the immune response. Feather pecking in laying hens is an important issue in animal welfare. Four studies in laying hens were selected which investigated increased or reduced pecking behaviour using direct or indirect measures of feather pecking behaviour...... consensus as to the relation between selection on pecking behaviour and laying performance and egg quality, d) Plasma serotonin level in the blood was reduced in the lines selected against pecking behaviour in both the individual selected lines and the group selected lines and there were indications...

  7. Effect of heterogeneity of nest boxes on occurrence of gregarious nesting in laying hens

    DEFF Research Database (Denmark)

    Clausen, Tina; Riber, Anja Brinch

    2012-01-01

    Gregarious nesting, where hens select already occupied nest boxes even when other nest boxes are unoccupied, is an unwanted behaviour in laying hens that may reduce animal welfare and pose a financial cost to the producer. It has been suggested that gregarious nesting is caused by the difficulties...... experienced by hens in distinguishing between nest boxes in long rows of identical boxes. Heterogeneity of nest boxes has therefore been suggested as a method to reduce gregarious nesting. To test this hypothesis two experiments were performed. Twelve groups of 13–15 ISA Warren hens 27 weeks of age were...... nesting was higher in experimental groups compared to control groups (P laying period did not differ between the experimental and control groups (P = 0.41). Numbers of visits to and eggs laid in nest boxes positioned either left or right were higher compared to nest boxes positioned...

  8. Effects of Lactobacillus acidophilus D2/CSL on laying hen performance

    National Research Council Canada - National Science Library

    Luigi Guidobono Cavalchini; Carla Orsi; Viviana Ferrazzi; Stefano Marelli; Maria Grazia Mangiagalli; Alberto Giardini; Daniele Gallazzi

    2010-01-01

    In order to evaluate the effects of dietary addition of probiotic strain Lactobacillus acidophilus D2/CSL on hen performance and egg quality, 160 commercial Hy-Line Brown pullets, 17 weeks old, were...

  9. Effect of oils sources on blood lipid parameters of commercial laying hens

    Directory of Open Access Journals (Sweden)

    LS Murata

    2003-12-01

    Full Text Available The experiment was carried out to verify if total cholesterol, HDL-cholesterol and triacylglicerol plasma levels are affected when laying hens are fed rations containing different dietary oil sources. One hundred sixty 50 week-old hens, assigned to four treatments with five replicates using 8 hens per replicate were used. The experimental period was of 84 days divided in 3 cycles of 28 days each. In the last day of each cycle, blood samples of 2 hens per replicate were randomly choose and blood samples were collected. On the other hand, blood was also collected at 7 am, 11 am and 3 pm aiming to study the daily changes of these lipids. Blood lipid parameters were not affected by different dietary oil sources (p > 0.05; however, HDL-cholesterol did change during the day, giving evidence that this lipid is indeed involved in the egg yolk formation.

  10. Effects of rearing systems on performance, egg characteristics and immune response in two layer hen genotype

    National Research Council Canada - National Science Library

    Küçükyılmaz, Kamil; Bozkurt, Mehmet; Herken, Emine Nur; Cınar, Mustafa; Catlı, Abdullah Uğur; Bintaş, Erol; Cöven, Fethiye

    2012-01-01

    .... Egg weight exhibited a similar pattern to that of laying performance. However, the total hen-housed egg number for the white birds in the organic system was fewer than that of white birds in the conventional cage facility...

  11. Protein-protein interaction networks identify targets which rescue the MPP+ cellular model of Parkinson’s disease

    Science.gov (United States)

    Keane, Harriet; Ryan, Brent J.; Jackson, Brendan; Whitmore, Alan; Wade-Martins, Richard

    2015-11-01

    Neurodegenerative diseases are complex multifactorial disorders characterised by the interplay of many dysregulated physiological processes. As an exemplar, Parkinson’s disease (PD) involves multiple perturbed cellular functions, including mitochondrial dysfunction and autophagic dysregulation in preferentially-sensitive dopamine neurons, a selective pathophysiology recapitulated in vitro using the neurotoxin MPP+. Here we explore a network science approach for the selection of therapeutic protein targets in the cellular MPP+ model. We hypothesised that analysis of protein-protein interaction networks modelling MPP+ toxicity could identify proteins critical for mediating MPP+ toxicity. Analysis of protein-protein interaction networks constructed to model the interplay of mitochondrial dysfunction and autophagic dysregulation (key aspects of MPP+ toxicity) enabled us to identify four proteins predicted to be key for MPP+ toxicity (P62, GABARAP, GBRL1 and GBRL2). Combined, but not individual, knockdown of these proteins increased cellular susceptibility to MPP+ toxicity. Conversely, combined, but not individual, over-expression of the network targets provided rescue of MPP+ toxicity associated with the formation of autophagosome-like structures. We also found that modulation of two distinct proteins in the protein-protein interaction network was necessary and sufficient to mitigate neurotoxicity. Together, these findings validate our network science approach to multi-target identification in complex neurological diseases.

  12. Effect of feeding hemp seed and hemp seed oil on laying hen performance and egg yolk fatty acid content: evidence of their safety and efficacy for laying hen diets.

    Science.gov (United States)

    Gakhar, N; Goldberg, E; Jing, M; Gibson, R; House, J D

    2012-03-01

    Forty-eight 19-wk-old Bovan White laying hens were fed 1 of 5 diets containing either hemp seed (HS) or hemp seed oil (HO). The level of HO was 4, 8, or 12%, whereas the level was 10 or 20% for the HS. A set of 8 birds fed wheat-, barley-, and corn oil-based diets served as the control. Performance was monitored over 12 wk. Average hen-day egg production was not affected upon feeding of either HS or HO diets. Egg weight was higher than that of the controls for hens consuming the 20% HS diet (P hens consuming the 12% HO diet. The total egg yolk n-3 fatty acid content increased linearly (P laying hens up to a maximum level of 20 and 12%, respectively, does not adversely effect the performance of laying hens and leads to the enrichment of the n-3 fatty acid content of eggs.

  13. Elastic-contractile model proteins: Physical chemistry, protein function and drug design and delivery.

    Science.gov (United States)

    Urry, Dan W; Urry, Kelley D; Szaflarski, Witold; Nowicki, Michal

    2010-12-30

    This review presents the structure and physico-chemical properties of ECMPs, elastic-contractile model proteins using sparse design modifications of elastic (GVGVP)(n); it describes the capacity of ECMP to perform the energy conversions that sustain living organisms; it arrives at the hydration thermodynamics of ECMP in terms of the change in Gibbs free energy of hydrophobic association, ΔG(HA), and the apolar-polar repulsive free energy of hydration, ΔG(ap); it applies ΔG(HA), ΔG(ap), and the nature of elasticity to describe the function of basic diverse proteins, namely - the F₁-motor of ATP synthase, Complex III of mitochondria, the KscA potassium-channel, and the molecular chaperonin, GroEL/ES; it applies ΔG(HA) and ΔG(ap) to describe the function of ABC exporter proteins that confer multi-drug resistance (MDR) on micro-organisms and human carcinomas and suggests drug modifications with which to overcome MDR. Using ECMP, means are demonstrated, for quantifying drug hydrophobicity with which to combat MDR and for preparing ECMP drug delivery nanoparticles, ECMPddnp, decorated with synthetic antigen-binding fragments, Fab1 and Fab2, with which to target specific up-regulated receptors, characteristic of human carcinoma cells, for binding and localized drug release. Copyright © 2010 Elsevier B.V. All rights reserved.

  14. The Littlf Red Hen%小红母鸡

    Institute of Scientific and Technical Information of China (English)

    柴博闻

    2011-01-01

    The Little Red Hen lives near a grain yard. She walks around and looks for worms every day. One day, she finds a seed--a wheat seed. She has never seen such a "worm". She tastes but finds it is different from the worms. She is a little puzzled.%小红母鸡住在一个谷场里,整天都到处走来走去,在各个地方找虫子吃。 一天,小红母鸡发现了一粒种子——小麦种子。她以前从来没有见过这样的“虫子”。于是,她轻轻地啄了它一下,发现它的味道和虫子一点都不一样,她感到很疑惑。

  15. Pharmacophore modeling for protein tyrosine phosphatase 1B inhibitors.

    Science.gov (United States)

    Bharatham, Kavitha; Bharatham, Nagakumar; Lee, Keun Woo

    2007-05-01

    A three dimensional chemical feature based pharmacophore model was developed for the inhibitors of protein tyrosine phosphatase 1B (PTP1B) using the CATALYST software, which would provide useful knowledge for performing virtual screening to identify new inhibitors targeted toward type II diabetes and obesity. A dataset of 27 inhibitors, with diverse structural properties, and activities ranging from 0.026 to 600 microM, was selected as a training set. Hypol, the most reliable quantitative four featured pharmacophore hypothesis, was generated from a training set composed of compounds with two H-bond acceptors, one hydrophobic aromatic and one ring aromatic features. It has a correlation coefficient, RMSD and cost difference (null cost-total cost) of 0.946, 0.840 and 65.731, respectively. The best hypothesis (Hypol) was validated using four different methods. Firstly, a cross validation was performed by randomizing the data using the Cat-Scramble technique. The results confirmed that the pharmacophore models generated from the training set were valid. Secondly, a test set of 281 molecules was scored, with a correlation of 0.882 obtained between the experimental and predicted activities. Hypol performed well in correctly discriminating the active and inactive molecules. Thirdly, the model was investigated by mapping on two PTP1B inhibitors identified by different pharmaceutical companies. The Hypol model correctly predicted these compounds as being highly active. Finally, docking simulations were performed on few compounds to substantiate the role of the pharmacophore features at the binding site of the protein by analyzing their binding conformations. These multiple validation approaches provided confidence in the utility of this pharmacophore model as a 3D query for virtual screening to retrieve new chemical entities showing potential as potent PTP1B inhibitors.

  16. Use of dietary thyroxine as an alternate molting procedure in spent turkey breeder hens.

    Science.gov (United States)

    Gulde, V A L; Renema, R; Bédécarrats, G Y

    2010-01-01

    In the turkey industry, molting is traditionally achieved by reducing photoperiod and withdrawing feed and water for several days. Although it is the most effective method, this practice is discouraged in Canada and alternative strategies need to be established. Thyroid hormone levels naturally change during molt, and dietary thyroxine (T4) supplementation was previously shown to induce molt in chickens. This study aimed at evaluating the effectiveness of supplemental dietary T4 in inducing molt in spent turkey breeder hens. One hundred twenty 75-wk-old hens were randomly divided into 4 groups (5 floor pens/replicates, 5 hens each) with the control group kept under a 14-h photoperiod and fed a breeder's diet throughout, whereas hens from the 3 other groups were supplemented with 40 ppm (45.76 mg/kg) T4 for 10 d. One treatment group was maintained under 14 h of light and fed a breeder's diet, whereas the 2 others were subjected to a drop in photoperiod to 6 h during or after supplementation and then were fed a maintenance diet. Egg production, feed intake, BW, molt, and plasma levels of T4, prolactin, and luteinizing hormone were measured. All treated hens ceased laying by d 20; however, several individuals spontaneously returned to lay when left on 14 h of light, suggesting incomplete involution of the reproductive tract. Supplementation significantly reduced feed consumption and induced rapid BW loss. All hens returned to their initial weight by the end of the experiment. Most treated hens initiated molt by d 8 of supplementation and all completed molt by d 37. Plasma T4 in treated hens increased significantly by d 3 (P dropping the photoperiod was necessary to completely reset the reproductive system.

  17. Validation of an automated mite counter for Dermanyssus gallinae in experimental laying hen cages

    OpenAIRE

    Mul, Monique; van Riel, Johan; Meerburg, Bastiaan; Dicke, Marcel; George, David; Groot Koerkamp, Peter

    2015-01-01

    For integrated pest management (IPM) programs to be maximally effective, monitoring of the growth and decline of the pest populations is essential. Here, we present the validation results of a new automated monitoring device for the poultry red mite (Dermanyssus gallinae), a serious pest in laying hen facilities world-wide. This monitoring device (called an “automated mite counter”) was validated in experimental laying hen cages with live birds and a growing population of D. gallinae. This va...

  18. The development of sausage including meat from spent laying hen surimi.

    Science.gov (United States)

    Jin, S K; Kim, I S; Jung, H J; Kim, D H; Choi, Y J; Hur, S J

    2007-12-01

    The sausage samples were made from pork with spent laying hen breast surimi. The samples were divided into 4 groups [sausage made from pork (control) and sausage made from pork with 20% (T1), 40% (T2), and 60% (T3) of spent laying hen breast surimi]. In proximate compositions, the moisture and ash contents of the control were higher than sausage containing spent laying hen surimi samples in all storage periods. The pH and cooking loss were higher in T3 compared with other sausage samples. However, there was no significant difference in water-holding capacity among the sausage samples, whereas shear force was significantly higher in T2. In meat color, sausage containing spent laying hen surimi samples (T1, T2, and T3) have shown to have higher lightness (L) compared with control, and redness (a) was significantly higher in control and T1. Total amino acid content and essential amino acids were increased in sausage containing spent laying hen surimi samples at 0 d of storage. In fatty acid composition, saturated fatty acid was higher in control than sausage containing spent laying hen surimi samples. Thiobarbituric acid reactive substances value was lower in sausage containing spent laying hen surimi samples than control at 2 and 4 wk of storage. Cholesterol content was lower in control compared with sausage containing spent laying hen surimi samples. In sensory evaluation, most test items were not significantly different among the sausage samples although tenderness was higher in T2 and T3 at 0 d of storage.

  19. Development and quality evaluation of dehydrated chicken meat rings using spent hen meat and different extenders

    OpenAIRE

    MISHRA, BIDYUT PRAVA; CHAUHAN, GEETA; Mendiratta, S. K.; B. D. Sharma; Desai, B. A.; Rath, P. K.

    2013-01-01

    It is recommended that for effective utilization of spent hen meat, it should be converted into value added or shelf stable meat products. Since we are lacking in cold chain facilities, therefore there is imperative need to develop shelf stable meat products. The present study was envisaged with the objective to develop dehydrated chicken meat rings utilizing spent hen meat with different extenders. A basic formulation and processing conditions were standardized for dehydrated chicken meat ri...

  20. Opinion of Belgian Egg Farmers on Hen Welfare and Its Relationship with Housing Type

    Science.gov (United States)

    Stadig, Lisanne M.; Ampe, Bart A.; Van Gansbeke, Suzy; Van den Bogaert, Tom; D’Haenens, Evelien; Heerkens, Jasper L.T.; Tuyttens, Frank A.M.

    2015-01-01

    Simple Summary Until 2012, laying hens in the EU were often housed in conventional cages that offered limited space and few opportunities to perform highly motivated behaviors. Conventional cages are now banned in the EU in order to improve animal welfare. In this study, egg farmers were surveyed (winter 2013–2014) to assess whether they perceived any changes in animal welfare since changing housing systems, what role hen welfare played in choosing a new housing system, and which aspects of hen welfare they find most important. The data show that the answers differ depending on which housing system the farmers currently use and whether they had used conventional cages in the past. Abstract As of 2012, the EU has banned the use of conventional cages (CC) for laying hens, causing a shift in housing systems. This study’s aim was to gain insight into farmers’ opinions on hen health and welfare in their current housing systems. A survey was sent to 218 Belgian egg farmers, of which 127 (58.3%) responded, with 84 still active as egg farmer. Hen welfare tended to be less important in choosing the housing system for farmers with cage than with non-cage systems. Respondents currently using cage systems were more satisfied with hen health than respondents with non-cage systems. Reported mortality increased with farm size and was higher in furnished cages than in floor housing. Feather pecking, cannibalism, smothering and mortality were perceived to be higher in current housing systems than in CC, but only by respondents who shifted to non-cage systems from previously having had CC. Health- and production-related parameters were scored to be more important for hen welfare as compared to behavior-related parameters. Those without CC in the past rated factors relating to natural behavior to be more important for welfare than those with CC. This difference in opinion based on farmer backgrounds should be taken into account in future research. PMID:26703742

  1. Levels of methoxylated polybrominated diphenyl ethers and polybrominated diphenyl ethers in hen eggs from China

    OpenAIRE

    2014-01-01

    PBDEs are widely used brominated flame retardant, which are increasingly reported in the environment. MeO-PBDEs are structural analogs to PBDEs, and reported as natural products and novel pollutants present in the environment. Concentrations of thirteen PBDEs and eight MeO-PBDEs in a large number of commercial sales of hen eggs representing 15 different regions and household productions of hen eggs representing 2 different regions collected from Hubei province of China were investigated in th...

  2. Sand intake by laying hens and its effect on egg production parameters.

    Science.gov (United States)

    van der Meulen, J; Kwakernaak, C; Kan, C A

    2008-08-01

    Soil intake may be the most prominent source of environmental contaminants for free range and organic hens, but there are no quantitative data concerning soil intake by domestic hens. Consumption of soil of 14-32 g a day can be estimated from literature, but such a dilution of nutrient intake seems incompatible with high productivity. In this study laying hens were fed pelleted diets with 0%, 10%, 20%, 25% and 30% of sand addition to determine its effect on productivity. Feed intake, feed and nutrient (feed minus sand) conversion ratio, egg production, egg weight and body weight gain were measured over a 4-week period. Acid insoluble ash concentration in the faeces was measured to determine the accuracy of estimating the soil ingestion by the soil-ingestion equation for wildlife as a way to determine soil ingestion of free range and organic hens under practical circumstances. The hens were able to compensate the dilution of the diet with 20%, 25% and 30% of sand by increasing their feed intake. Feed intake increased significantly and feed to egg conversion ratio decreased significantly with increasing sand levels in the diet. The nutrient to egg conversion ratio of the diet without sand tended to be worse than for the diets with sand, presumably due to the total absence of coarse material in the diet. There were no differences in egg production and egg weight between hens fed the different diets but body weight gain was significantly lower for the hens fed the diets with 20%, 25% and 30% of sand. Estimation of sand ingestion was done by the soil-ingestion equation for wildlife. Provided that the actual dry matter digestibility coefficient of the nutrient part of the diet is taken into account, estimating the soil ingestion according to the soil-ingestion equation for wildlife seems an appropriate way to determine soil ingestion for free range and organic hens under practical circumstances.

  3. Quality and stability of eggs from laying hens fed with organic minerals and lycopene

    OpenAIRE

    Flavia Kleszcz da Cruz; Elis Regina de Moraes Garcia; André Luiz Julien Ferraz; Karina Márcia Ribeiro de Souza; William Britez Feliciano; Rosileide Vilalba Rohod

    2016-01-01

    ABSTRACT: This study aimed to evaluate the effect of using lycopene and organic minerals in diets for laying hens on the egg quality and stability of eggs stored for 30 days under different storage environments. An entirely randomized design was adopted in 2x3x3 factorial scheme (mineral sources x lycopene levels x storage periods) with six replicates of eight hens per experimental unit. The experimental diets were: feed containing inorganic minerals (IM) without added lycopene; IM with added...

  4. Supplementation with humic substances affects the innate immunity in layer hens in posfasting phase

    OpenAIRE

    Rosa Sanmiguel P.; Iang Rondón B

    2015-01-01

    ABSTRACT Objective. Asses the effect of supplementation with Humic substances (HS) over some innate immunity parameters (serum bactericidal activity, phagocytosis, bacterial agglutination, respiratory burst and lisozyme activity) in phase after fasting of layer hens. Materials and methods. 120 posfasting phase Hy Line Brown layer hens were taken which were distributed into four groups: The first and the second were supplemented with 0.1 and 0.2% of HS, respectively. The third group was supple...

  5. Phytate phosphorus utilization and intestinal phytase activity in laying hens

    Directory of Open Access Journals (Sweden)

    Alaeldein M. Abudabos

    2012-01-01

    Full Text Available The first aim of this study was to examine the effects of strain and age on phytate phosphorus (PP utilization and intestinal phytase activity (IPA in two strains of laying hens, Hy-line Brown (HB and Hy-line White W-36 (HW at 32, 52 and 72 weeks of age. A digestion trial was conducted using the indicator method and birds were sampled to measure IPA. The second aim was to examine the effect of feed grade exogenous phytase enzyme on total (TP, water soluble (WSP and phytate phosphorus (PP excretion in the HW strain fed varying levels of phosphorus. Hens were fed three concentrations of available P (AP: 0.2, 0.3 and 0.4%. Each level of P was supplemented with three levels of commercial feed grade exogenous phytase enzyme (0, 300, and 600 FTU/kg and the amount of TP, WSP and PP in excreta per 100 g of feed consumed was calculated. The HB retained more PP as compared to HW. Intestinal phytase activity showed a significant (P<0.01 age effect with the highest activity occurring at 32 weeks. There were significant differences in the amount of TP and SP excreted between birds receiving the 3 levels of phosphorus with 300 units phytase (P<0.01. The results of this study showed that layers are capable of utilizing PP, and that utilization is regulated by IPA and varies with age. Exogenous phytase improved PP utilization but it increased the amount of TP and WSP in excreta.

  6. Physical modeling of geometrically confined disordered protein assemblies

    Science.gov (United States)

    Ando, David

    2015-08-01

    The transport of cargo across the nuclear membrane is highly selective and accomplished by a poorly understood mechanism involving hundreds of nucleoporins lining the inside of the nuclear pore complex (NPC). Currently, there is no clear picture of the overall structure formed by this collection of proteins within the pore, primarily due to their disordered nature and uncertainty regarding the properties of individual nucleoporins. We first study the defining characteristics of the amino acid sequences of nucleoporins through bioinformatics techniques, although bioinformatics of disordered proteins is especially challenging given high mutation rates for homologous proteins and that functionality may not be strongly related to sequence. Here we have performed a novel bioinformatic analysis, based on the spatial clustering of physically relevant features such as binding motifs and charges within disordered proteins, on thousands of FG motif containing nucleoporins (FG nups). The biophysical mechanism by which the critical FG nups regulate nucleocytoplasmic transport has remained elusive, yet our analysis revealed a set of highly conserved spatial features in the sequence structure of individual FG nups, such as the separation, localization, and ordering of FG motifs and charged residues along the protein chain. These sequence features are likely conserved due to a common functionality between species regarding how FG nups functionally regulate traffic, therefore these results constrain current models and eliminate proposed biophysical mechanisms responsible for regulation of nucleocytoplasmic traffic in the NPC which would not result in such a conserved amino acid sequence structure. Additionally, this method allows us to identify potentially functionally analogous disordered proteins across distantly related species. To understand the physical implications of the sequence features on structure and dynamics of the nucleoporins, we performed coarse-grained simulations

  7. Optimization of an industrial retrofitted heat exchanger network, using a stage-wise model

    Energy Technology Data Exchange (ETDEWEB)

    Kovac Kralj, Anita [Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova 17, Maribor 2000 (Slovenia)

    2010-12-15

    The heat exchanger network (HEN) can be optimized using the stage-wise model of superstructure representation, as proposed by Yee and Grossmann. This model can be easily solved regarding both trivial problems, and serious and complex new industrial design plants. In this paper, a stage-wise model for new designs is extended for retrofits by using a stage-wise model for a retrofitted HEN. This method using a stage-wise model is very general; it can be used in new designs as well as during existing process integration. The methodology of the stage-wise model for retrofitted HEN can be used to solve HENs easily and well enough, over a short time, and simultaneously. A mathematical model of stage-wise for retrofit HEN can include additional equations and limitations for retrofits. This model was tested by using a retrofitted methanol process generating an additional profit of 189,200 EUR/a. (author)

  8. A morpho-kinematic and spectroscopic study of the bipolar nebulae: M 2-9, Mz 3, and Hen 2-104

    CERN Document Server

    Clyne, Niall; Steffen, Wolfgang; Redman, Matt; Goncalves, Denise R; Harvey, Eamonn

    2015-01-01

    Context. Complex bipolar shapes can be generated either as a planetary nebula or a symbiotic system. The origin of the material ionised by the white dwarf is very different in these two scenarios, and it complicates the understanding of the morphologies of planetary nebulae. Aims. The physical properties, structure, and dynamics of the bipolar nebulae, M 2-9, Mz 3, and Hen 2-104, are investigated in detail with the aim of understanding their nature, shaping mechanisms, and evolutionary history. Methods. Long-slit optical echelle spectra are used to investigate the morpho-kinematics of M 2-9, Mz 3, and Hen 2-104. Near-infrared (NIR) data, as well as optical, spectra are used to separate Galactic symbiotic-type nebulae from genuine planetary nebulae by means of a 2MASS J-H/H-Ks diagram and a {\\lambda}4363/H{\\gamma} vs. {\\lambda}5007/H\\b{eta} diagnostic diagram, respectively. Results. The best-fitted 3-D models for M 2-9, Mz 3, and Hen 2-104 provide invaluable kinematical information on the expansion velocity of...

  9. Analysis and Ranking of Protein-Protein Docking Models Using Inter-Residue Contacts and Inter-Molecular Contact Maps

    KAUST Repository

    Oliva, Romina

    2015-07-01

    In view of the increasing interest both in inhibitors of protein-protein interactions and in protein drugs themselves, analysis of the three-dimensional structure of protein-protein complexes is assuming greater relevance in drug design. In the many cases where an experimental structure is not available, protein-protein docking becomes the method of choice for predicting the arrangement of the complex. However, reliably scoring protein-protein docking poses is still an unsolved problem. As a consequence, the screening of many docking models is usually required in the analysis step, to possibly single out the correct ones. Here, making use of exemplary cases, we review our recently introduced methods for the analysis of protein complex structures and for the scoring of protein docking poses, based on the use of inter-residue contacts and their visualization in inter-molecular contact maps. We also show that the ensemble of tools we developed can be used in the context of rational drug design targeting protein-protein interactions.

  10. Comparative histomorphometrical study of genital tract in adult laying hen and duck.

    Science.gov (United States)

    Mohammadpour, Ahmad-Ali; Zamanimoghadam, Abdolkarim; Heidari, Massoumeh

    2012-01-01

    This study was carried out to compare the histomorphological structures of oviductal regions of the apparently healthy adult laying hens (Gallus gallus dometicus) and ducks (Ansa ansa domesticus). For this purpose, 20 hens and 20 female ducks aged between 1-1.5 years were used. After euthanasia, the oviducts were dissected out and all of the gross morphometrical parameters including length, width and thickness as well as weight and length of them were recorded. For histological studies, after tissue preparation and staining with H&E, histological layers of isthmus, uterus and vagina were recognized and the size of them with micrometry method were determined. Our data analyses indicated that, the mean weight, length of oviduct as well as weight of isthmus, uterus in hen were significantly (P hen. In histological studies, epithelium and cilia were well developed in duck and lamina propria was filled with glands in the regions of the isthmus and uterus. The length of primary mucosal folds of isthmus and uterus in duck was more than hen. The longest mucosal fold has been seen in uterus. Most of the parameters in duck were greater than hen except the length of secondary fold of three parts of oviduct including isthmus, uterus, and vagina.

  11. Effect of Calcium Sources and Particle Size on Performance and Eggshell Quality in Laying Hens

    Directory of Open Access Journals (Sweden)

    Arzu Erol Tunç

    2015-01-01

    Full Text Available An experiment was conducted to determine the effect of different combination calcium sources and particle size on performance and egg shell quality in layer hens. In the experiment, 198 brown laying hens at 44 week of age were randomly assigned into 11 treatments groups. The experimental diets consisted of different calcium sources (Fine limestone, large limestone, large oyster shell and large egg shell and their different combination. The experimental unit consisted of a groups of three hens, thus each treatment was replicated six times. Different calcium sources and particle size addition to the laying hens diet had no significantly effect on body weight gain, egg production, egg mass, feed intake, feed conversion ratio, egg specific gravity, egg shell weight, egg shell thickness and egg shell breaking strength but egg weight had significantly affected by the treatments. The significantly highest egg weight was found in laying hens fed with 50 % fine limestone and 50 % large limestone. Dietary different Ca sources had a significant effect on Ca, P and Mg as mineral contents of eggshell and tibia. In the present study, when dietary large calcium sources (limestone, oyster shell and egg shell had no effect on performance and eggshell quality parameters in laying hens. However, dietary containing at least 50 % large calcium sources had positive effect on mineral contents of tibia.

  12. Corticosterone and fear behaviour in white and brown caged laying hens.

    Science.gov (United States)

    Fraisse, F; Cockrem, J F

    2006-04-01

    Physiological and behavioural measures of stress in caged hens on a commercial farm were compared between White Leghorn and brown Hyline strains, and between three tiers of cages. Blood and faecal samples were collected from undisturbed birds for corticosterone measurements. Plasma corticosterone responses to a stressor were measured by the collection of blood samples after 15, 30, and 60 min of a handling stressor. Tonic immobility and novel object tests were used to measure fear behaviour. Plasma corticosterone in undisturbed hens and faecal corticosterone did not differ between White Leghorn and brown Hyline hens, whereas the plasma corticosterone response to a handling stressor was greater in White Leghorns. The duration of tonic immobility, latency to first head movement and number of head movements in tonic immobility tests were greater in white than brown birds, whereas the number of inductions was less for tonic immobility tests. There were no differences between the strains in their responses to a novel object. There were no differences between tiers in plasma corticosterone or corticosterone responses or tonic immobility responses, and no consistent differences in responses of birds to a novel object. This is the first study in which plasma and faecal corticosterone concentrations and fear behaviour have been measured together in laying hens, and the first description of plasma corticosterone responses to handling over 60 min for caged laying hens on a commercial farm. The study has shown the value of measuring endocrine and behavioural variables together to provide objective data on characteristics of different strains of hens.

  13. Reduced productivity among confined laying hens infested by Allopsoroptoides galli (Mironov, 2013).

    Science.gov (United States)

    Soares, N M; Tucci, E C; Freitas, E R; Fernandes, D P B

    2016-04-01

    The mite Allopsoroptoides galli has recently been identified parasitizing commercial chickens, São Paulo State/Brasil, causing severe dermatitis on all parts of the animal's body and a significant decline in productivity, particularly in egg production. The aim of the present study in A. galli infestation was to investigate the impact on laying hens' performance and egg quality. A total of 100 56-week-old Hy-line white laying hens were used. The birds were divided into 2 groups, with 10 replicates of 5 birds in each group. The experimental groups consisted of a non-infested group (hens free of theA. galli) and an infested group (hens presenting A. galli). The infestation with A. galli did not significantly influence feed intake but caused a significant reduction in the body weight of the hens and caused a decrease in egg production, therefore promoting worse feed conversion. The egg weight was reduced; however, the infestation did not significantly affect the internal quality of the eggs, which was measured according to the yolk color, albumen height, and Haugh units, or the quality of the shell, based on its percentage, thickness, and strength. It can be concluded that anA. galli infestation promotes a reduction in body weight, egg production, and egg weight in laying hens, therefore worsening feed conversion.

  14. Responsiveness to a novel preening stimulus long after partial beak amputation (beak trimming) in laying hens.

    Science.gov (United States)

    van Liere, D W

    1995-07-01

    Thirty beak-trimmed and thirty intact hens were reared in mixed groups and individually housed in battery cages; partial beak amputation took place 6 weeks after hatching. All hens were tested with a novel stimulus when they were 42 weeks old: a small paper sticker (36 mm(2)) was attached to the distal parts of the feathers at the ba