Ruminant Nutrition and Production in the Tropics and Subtropics

Livestock Production/Industries,

Synthesis of empty bacterial microcompartments, directed organelle protein incorporation, and evidence of filament-associated organelle movement

Compartmentalization is an important process, since it allows the segregation of metabolic activities and, in the era of synthetic biology, represents an important tool by which defined microenvironments can be created for specific metabolic functions. Indeed, some bacteria make specialized proteinaceous metabolic compartments called bacterial microcompartments (BMCs) or metabolosomes. Here we demonstrate that the shell of the metabolosome (representing an empty BMC) can be produced within E. coil cells by the coordinated expression of genes encoding structural proteins. A plethora of diverse structures can be generated by changing the expression profile of these genes, including the formation of large axial filaments that interfere with septation. Fusing GFP to PduC, PduD, or PduV, none of which are shell proteins, allows regiospecific targeting of the reporter group to the empty BMC. Live cell imaging provides unexpected evidence of filament-associated BMC movement within the cell in the presence of Pdu

Degradability of mulberry (Morus alba) and rice bran in the rumen of sheep fed different diets

The experiment was conducted to investigate degradation of dry matter (DM) and protein of mulberry and rice bran when incubated in nylon bag in the rumen at different incubation times and different rumen environments of rumen-cannulated adult sheep. Three different rumen conditions were created by feeding the three rumen-cannulated sheep with urea-treated rice straw as basal diet and offered with three supplemental treatment diets on different source of energy and nitrogen. Mulberry, urea and rice bran were used as source of fermentable energy and protein. Treatments consisted of control diet mulberry and molasses (T0); 50% mulberry was replaced by rice bran and urea (T1); and 100% of mulberry was replaced with rice bran and urea (T2). The diets were formulated in iso protein and iso energy. Supplemental diets were offered at 1.2% BW. The study was conducted in three periods. For each period, the sheep was offered with one of three supplemental treatment diets. The nylon bags each, contains sample of either mulberrry or rice bran were incubated in the rumen of sheep at different incubation times in reverse order (48, 24, 12, 9, 6, and 3h). Degradation characteristic data were obtained by analyzing degradability data with the equation of p = a+b(1-e-ct) using Neway computer package. Data of degradation characteristic, degradability of DM and CP, DMI, rumen NH3-N and pH were subjected to analysis of variance (ANOVA) using a SAS software package. The results showed that the dry matter intake (DMI) and rumen pH were not significantly different between diets. The rumen ammonia concentration of T1 and T2 was significantly higher than that of T0. However, the rumen ammonia concentration was higher than that of critical value for rumen microbial synthesis (5mg/100ml). The rate (c value) of DM degradability of mulberry and rice bran was affected by diet treaments, where T2 diet resulted in lower c of mulberry and rice bran. Only CP degradability of mulberry on the other hand was affected by diet treatments. But, both CP mulberry and rice bran had high degradability (80% after 24 hs incubation) in all diet treatments. It is concluded that the three diets of this study were capable of creating the optimum condition for rumen fermentation. Supplementation of mulberry or urea-rice bran mixture had similar effect on protein degradability of rice bran. On the other hand, the rate of protein degradability of mulberry was reduced when it was incubated in the rumen of sheep fed urea rice bran mix supplement.       Key Words: Mulberry, Rice Bran, Rumen Degradability, Shee

The use of in vitro gas production technique to evaluate molasses supplementation to mulberry (morus alba) and rice straw mixed diets

Mulberry foliages have high nutritive value (protein content, digestibility and degradability), therefore it is potential to be used as a supplement to poor quality roughages. The objective of this experiment was to evaluate the effect of addition of fermentable energy in the mixed of mulberry and rice straw basal diet. A control diet consisted of either rice straw (RS) or urea treated rice straw mixed with mulberry foliage (URS) with ratio of 60 : 40%. Treatment was formulated by supplementation of control diet with molasses (as sources of fermentable energy) at 3 levels (5, 10 and 15%). The study was conducted in a 2 x 4 factorial experiment, consisted of 2 levels rice straw (untreated and urea treated) and 4 levels molasses supplementation (control and 3 levels for molasses). Diets were evaluated using in vitro gas production. The fermentation kinetics was determined from the incubation of 200 mg sample during 96 hours. The calculation of the kinetics based on exponential equation P = A+ B (1-e-ct). A shorter gas production test was carried out to determine truly degradable fermented substrates (in vitro true organic matter degradability/IVTOMD) by incubating 500 mg of samples 24 hours. The result showed that there was no significant interaction between rice straw treatment and molasses supplementation on fermentation characteristics, in vitro true dry matter digestibility, fermented substrate and total volatile fatty acid (VFA) production. However there was a significant interaction between rice straw treatment on partitioning factor (PF), gas produced, propionic acid production and ratio between acetic acid and propionic acid. Molasses supplementation significantly (P0.05) decreased gas production and ratio of acetic to propionic acid, and increase PF, propionic acid production in untreated rice straw mulberry (RSM) basal diet. It is concluded that molasses supplementation to RSM diet decreased gas production and ratio of C2/C3, and increased PF and propionic acid production. Key Words: Mulberry Foliage, Molasses, Rice Straw, In Vitro Gas Productio

Cosmological constraints on the generalized holographic dark energy

We use the Markov ChainMonte Carlo method to investigate global constraints on the generalized holographic (GH) dark energy with flat and non-flat universe from the current observed data: the Union2 dataset of type supernovae Ia (SNIa), high-redshift Gamma-Ray Bursts (GRBs), the observational Hubble data (OHD), the cluster X-ray gas mass fraction, the baryon acoustic oscillation (BAO), and the cosmic microwave background (CMB) data. The most stringent constraints on the GH model parameter are obtained. In addition, it is found that the equation of state for this generalized holographic dark energy can cross over the phantom boundary wde =-1.Comment: 14 pages, 5 figures. arXiv admin note: significant text overlap with arXiv:1105.186

Prebiotic effects of oligosaccharides extracted from palm kernel expeller on different levels of Salmonella typhimurium infection in chicks

Prebiotic effects of oligosaccharides extract from palm kernel expeller (OligoPKE) on Salmonella typhimurium were investigated in chicks in two experiments. Results of the first experiment showed that OligoPKE reduced the colonization of Salmonella typhimurium in the cecum and increased the immunoglobulin A (IgA) production in the blood and jejunum. The second experiment further investigated the prebiotic efficacy of dietary supplementation of OligoPKE on three levels of Salmonella typhimurium infection (1.0 x 104 Colony-forming unit (CFU)/mL; 1.0 x 106 CFU/mL and 1.0 x 108 CFU/mL) in chicks. OligoPKE reduced the colonization of Salmonella in the medium and high levels of infection. IgA level in serum and jejunum content increased significantly in all the three levels of infection when chicks received OligoPKE in their diet. Interleukin 8, and 10; interferon-α; and tumour necrosis factor genes were up-regulated in the jejunum of the infected chicks, and OligoPKE down-regulated these gene expressions. Results of the current study indicated that OligoPKE, an oligosaccharides extract from palm kernel expeller, is capable of reducing colonization of Salmonella typhimurium in young chicks, and boosted their immunity.Keywords: chicken, immunoglobulin, immune gene, microbial populatio

Does accelerating universe indicates Brans-Dicke theory

The evolution of universe in Brans-Dicke (BD) theory is discussed in this paper. Considering a parameterized scenario for BD scalar field $\phi=\phi_{0}a^{\alpha}$ which plays the role of gravitational "constant" $G$, we apply the Markov Chain Monte Carlo method to investigate a global constraints on BD theory with a self-interacting potential according to the current observational data: Union2 dataset of type supernovae Ia (SNIa), high-redshift Gamma-Ray Bursts (GRBs) data, observational Hubble data (OHD), the cluster X-ray gas mass fraction, the baryon acoustic oscillation (BAO), and the cosmic microwave background (CMB) data. It is shown that an expanded universe from deceleration to acceleration is given in this theory, and the constraint results of dimensionless matter density $\Omega_{0m}$ and parameter $\alpha$ are, $\Omega_{0m}=0.286^{+0.037+0.050}_{-0.039-0.047}$ and $\alpha=0.0046^{+0.0149+0.0171}_{-0.0171-0.0206}$ which is consistent with the result of current experiment exploration, $\mid\alpha\mid \leq 0.132124$. In addition, we use the geometrical diagnostic method, jerk parameter $j$, to distinguish the BD theory and cosmological constant model in Einstein's theory of general relativity.Comment: 16 pages, 3 figure

Abnormal phenomena in a one-dimensional periodic structure containing left-handed materials

The explicit dispersion equation for a one-dimensional periodic structure with alternative layers of left-handed material (LHM) and right-handed material (RHM) is given and analyzed. Some abnormal phenomena such as spurious modes with complex frequencies, discrete modes and photon tunnelling modes are observed in the band structure. The existence of spurious modes with complex frequencies is a common problem in the calculation of the band structure for such a photonic crystal. Physical explanation and significance are given for the discrete modes (with real values of wave number) and photon tunnelling propagation modes (with imaginary wave numbers in a limited region).Comment: 10 pages, 4 figure

Magnetic and pair correlations of the Hubbard model with next-nearest-neighbor hopping

A combination of analytical approaches and quantum Monte Carlo simulations is used to study both magnetic and pairing correlations for a version of the Hubbard model that includes second-neighbor hopping $t^{\prime }=-0.35t$ as a model for high-temperature superconductors. Magnetic properties are analyzed using the Two-Particle Self-Consistent approach. The maximum in magnetic susceptibility as a function of doping appears both at finite $$ and at $t^{\prime }=0$ but for two totally different physical reasons. When $t^{\prime }=0$, it is induced by antiferromagnetic correlations while at $t^{\prime }=-0.35t$ it is a band structure effect amplified by interactions. Finally, pairing fluctuations are compared with $$-matrix results to disentangle the effects of van Hove singularity and of nesting on superconducting correlations. The addition of antiferromagnetic fluctuations increases slightly the $d$-wave superconducting correlations despite the presence of a van Hove singularity which tends to decrease them in the repulsive model. Some aspects of the phase diagram and some subtleties of finite-size scaling in Monte Carlo simulations, such as inverted finite-size dependence, are also discussed.Comment: Revtex, 8 pages + 15 uuencoded postcript figure

Elastic scattering and breakup of 17^F at 10 MeV/nucleon

Angular distributions of fluorine and oxygen produced from 170 MeV 17^F incident on 208^Pb were measured. The elastic scattering data are in good agreement with optical model calculations using a double-folding potential and parameters similar to those obtained from 16^O+208^Pb. A large yield of oxygen was observed near \theta_lab=36 deg. It is reproduced fairly well by a calculation of the (17^F,16^O) breakup, which is dominated by one-proton stripping reactions. The discrepancy between our previous coincidence measurement and theoretical predictions was resolved by including core absorption in the present calculation.Comment: 9 pages, 5 figure