Mahoneywren4400

There are numerous microorganisms in nature capable of synthesizing diverse useful compounds; however, these natural microorganisms are generally inefficient in the production of target products on an industrial scale, relative to either chemical synthesis or extraction methods. To achieve industrial production of useful compounds, these natural microorganisms must undergo a certain degree of mutation or effective fine-tuning strategies. This review describes how to achieve an ideal metabolic fine-tuned process, including static control strategies and dynamic control strategies. The static control strategies mainly focus on various matabolic engineering strategies, including protein engineering, upregulation/downregulation, and combinatrorial control of these metabolic engineering strategies, to enhance the flexibility of their application in fine-tuned metabolic metworks. Then, we focus on the dynamic control strategies for fine-tuned metabolic metworks. The design principles derived would guide us to construct microbial cell factories for various useful compounds.The undigested nitrogenous fraction entering the hindgut of chickens is further metabolized by microbiota present producing volatile basic metabolites including amines and ammonia (NH3). Ammonia increases pH and may result in overgrowth of Clostridium perfringens further producing toxic metabolites that cause dysbacteriosis or necrotic enteritis (NE). There are few reports in chickens examining the production and concentration of nitrogenous metabolites in the hindgut. A Berthelot reaction using an automated flow, reaction and spectrophotometric instrumentation to detect volatile basic nitrogen in the form of NH3 from cecal contents was carried out. In the Berthelot reaction, NH3 in the sample is chlorinated to monochloramine using dichloroisocyanuric acid that then reacts with salicylate to form 5-aminosalicylate which is stable under alkaline conditions (pH 12 to 13). After oxidation and oxidative coupling, a coloured complex is formed that can be measured at 660 nm. Cecal contents were collected and pooled from 2 birds per pen with 48 pens total in each of 3 experiments and stored in sealed containers at -20 °C prior to analysis. Experiment 1 compared samples collected from birds fed either no meat and bone meal (MBM) or 6% MBM from d 0 to 14, and samples collected from birds fed either no MBM or 5% MBM from d 14 to 42. All birds were challenged with Eimeria on d 9 and C. perfringens on d 14 and 15. Experiment 2 compared cecal contents from birds fed either 0.5% or 0.9% calcium (Ca), and Exp. 3 compared unchallenged with NE challenge on d 16 and 29. Results demonstrated an increase (P less then 0.05) in cecal NH3 as a result of feeding MBM or high dietary Ca with a corresponding increase in pH. Birds experimentally challenged with NE had lower cecal NH3 and lower pH on d 16 but not d 29 compared to unchallenged controls. It was concluded that the Berthelot method using Skalar instrumentation equipment is suitable to measure the concentration of volatile nitrogen as NH3 in cecal contents of chickens.Fertile chicken eggs were used as an alternative model for large animals to evaluate suspect toxic dietary ingredients for fetal loss disorders associated with mare reproductive loss syndrome (MRLS) and fetal losses in other livestock. Nitrate, ammonia, and sulfate may react with proteinaceous compounds to enable the formation of abiotic pathogenic nanoparticles which were constant findings in pathognomonic placental lesions associated with non-infectious fetal losses of previously unknown etiology in mares, chickens and other livestock. The pathogenic nanoparticles may be produced naturally by toxic elements associated with air pollution that affect pasture forages or crops, unintentionally by reactions of these elements in protein-mineral mixes in dietary rations, or endogenously within tissues of fetuses and adult animals. The nanoparticles may form niduses in small vessels and predispose animals to a host of secondary opportunistic diseases affecting the reproductive, respiratory and gastrointestinal tracts of animals. The newly recognized abiotic pathogenic micro and nanoparticles are associated with MRLS. The discovery of the pathogenic nanoparticles led to the identification of nitrate, ammonium, and sulfur, in the form of sulfate, that seemingly enable the formation of the pathogenic nanoparticles in embryonic and fetal tissues.As a kind of green additive, pectic oligosaccharide (POS) may regulate some physiological functions of animals, such as gut health, antioxidant capacity, immunity and lipid metabolism. This study aimed to identify whether POS administration can improve maternal reproduction, and to determine the possible metabolism. A total of 48 pregnant Wistar rats randomly allotted into 2 groups, and each group was fed a diet supplemented with 0 or 800 mg/kg of POS. Pectic oligosaccharide administration increased rat born number (P less then 0.05), did not affect rat embryo number on d 7 of gestation, but increased rat fetus number on d 14 of gestation (P less then 0.05). On d 14 of gestation, POS treatment improved Lactobacillus and Bifidobacterium populations and volatile fatty acid concentrations of cecal digesta (P less then 0.05), hormone (progesterone and nitric oxide) and cytokine (interleukin 2) concentrations of serum (P less then 0.05), and antioxidant capacity of serum (increased total antioxidant capacity and decreased malondialdehyde) and placenta (increased total superoxide dismutase, decreased malondialdehyde) (P less then 0.05) in pregnant rats. find more These results suggest that POS administration improved rat reproduction via decreasing fetus loss in middle gestation. This was due to the increased volatile fatty acid concentrations in rat gut improving hormone and inflammatory-cytokine productions, and antioxidant capacity.The present study explored effects of L-glutamate (Glu) levels on growth, digestive and absorptive capability, and intestinal physical barrier functions of Jian carp (Cyprinus carpio). A total of 600 Jian carp (126.40 ± 0.21 g) were randomly distributed into 5 groups with 3 replicates each, fed diets containing graded levels of Glu (53.4 [control], 57.2, 60.6, 68.4, and 83.4 g/kg) for 63 d. Results showed compared with control diet, feed intake and percent weight gain (PWG) in fish fed 83.4 g of Glu/kg diet were increased and feed conversion ratio in fish fed 68.4 g of Glu/kg diet was decreased (P less then 0.05). Similarly, body crude protein and lipid contents in fish fed 68.4 g of Glu/kg diet were higher (P less then 0.05). The activities of trypsin and chymotrypsin in the hepatopancreas and intestine, and amylase, alkaline phosphatase (AKP), Na+, K+-ATPase (NKA), and creatine kinase (CK) in intestine were higher in fish fed 68.4 g of Glu/kg diet (P less then 0.05). Dietary Glu (57.2 to 83.4 g/kg dieestive and absorptive ability, and intestinal physical barrier functions. Based on the quadratic regression analysis of PWG, and MDA of the hepatopancreas and intestine, the optimal dietary Glu levels were estimated to be 81.97, 71.06, and 71.36 g/kg diet, respectively.Within a given free-range flock, some hens prefer to spend the majority of their time in the shed (stayers), while others frequently access the range (rangers). Laying performance has been associated not only with the development of these sub-populations but also with different body weights (BW). The purpose of this study was to determine if range usage, BW or a combination of both is associated with energy metabolism and as such contribute to improved hen performance. Forty-eight Lohmann Brown hens at 74 wk of age were selected from a commercial free-range farm based on their BW and range usage over a 56-week period. Using a 2 × 2 factorial arrangement, hens were either classified as heavy (mean ± SEM; 2.01 ± 0.02 kg, n = 24) or light (1.68 ± 0.01 kg, n = 24), and also classified as rangers (accessed the range for 84.1% of available days, 242 ± 3.75 d; n = 24) or stayers (accessed the range for 7.17% of available days; 23.4 ± 6.08 d, n = 24). Stayers had significantly higher metabolizable energy (ME) intake feed utilisation compared to the light stayers.The research was aimed at studying the efficiency of a nanoscale alloy of copper (Cu) and zinc (Zn) to be used as a mineral additive for feeding broiler chickens, compared to inorganic and organic forms of these elements. Biochemical studies of the blood serum were performed using an automated analyzer. The mineral composition was determined by atomic emission and mass spectrometry (MS-ISP). The study was performed on broiler chickens of cross Smena 7 (n = 72) in the conditions of a vivarium. There were 3 treatment groups with 24 chickens in each. Replacing the inorganic form of mineral supplements with the nanosized alloy resulted in a positive productive effect, with a tendency to increasing the content of serum protein. The nanoscale form of metals improved (P ≤ 0.05) the activity of aminotransferases. At the same time, the liver microstructure of experimental groups is similar to that of the control. There was a moderate plethora and poor polymorphoncellular infiltration around the interlobular triads witby 66.8% (P ≤ 0.01) only at the end of the experiment. Thus, nanoscale forms of Cu and Zn have a cumulative effect, and may become an alternative to inorganic and organic forms of these elements in poultry nutrition.A study was conducted to evaluate the effect of the dietary inclusion of full-fat flaxseed or full-fat sunflower seeds on performance parameters, egg quality parameters and egg yolk fatty acid profile in laying hens. A total of 150 Babcock Brown hens at 27 weeks of age were distributed in 3 experimental treatments, as follows T1, control; T2, diet containing 13.5% full-fat whole flaxseed seeds; and T3, diet containing 13.5% full-fat ground sunflower seeds. Feed and water were provided ad libitum and the experiment lasted for 8 weeks. No significant differences were found on egg quality parameters, but total egg production and rate of lay were significantly (P less then 0.05) lower in the group receiving sunflower seeds compared with the control, and significant differences (P less then 0.05) in egg yolk saturated, monounsaturated, polyunsaturated, omega-6 (n-6) and omega-3 (n-3) fatty acids were observed, as well as in the n-6n-3 ratio. The results show that the dietary inclusion of 13.5% flaxseed full-fat seeds significantly increases the n-3 polyunsaturated fatty acid (PUFA) content in the eggs and lowers the n-6n-3 ratio without affecting performance parameters. Inclusion of full-fat sunflower seeds increases the n-6 PUFA content but affects total egg production and rate of lay. Further studies are needed to determine the level of inclusion of full-fat sunflower seeds that does not affect performance.The hypothesis that capping dietary starchprotein ratios would enhance the performance of broiler chickens offered reduced-crude protein (CP) diets was tested in this experiment. A total of 432 off-sex, male Ross 308 chicks were allocated to 7 dietary treatments from 7 to 35 d post-hatch. The experimental design consisted of a 3 × 2 factorial array of treatments with the seventh treatment serving as a positive control. Three levels of dietary CP (197.5, 180.0 and 162.5 g/kg) with either uncapped or capped dietary starchprotein ratios constituted the factorial array of treatments, whilst the positive control diet contained 215.0 g/kg CP. The positive control diet had an analysed dietary starchprotein ratio of 1.50 as opposed to a ratio of 1.68 in the uncapped 197.5 g/kg CP diet and 1.41 in the corresponding capped diet and the capped 197.5 g/kg CP diet displayed promise. The growth performance this diet matched the positive control but outperformed the uncapped 197.5 g/kg CP diet by 10.4% (2,161 vs. 1,958; P = 0.