Influence of non starch polysaccharide-degrading enzymes on the meat yield and viscosity of jejunal digesta in broilers fed wheat/barley-based diet

This study was conducted to investigate the effect of four commercial multi-enzymes on the performance, meat yield, water intake, litter moisture and jejunal digesta viscosity of chicks fed wheat/barley based diet. A total of 195 1-d-old male broiler chicks (Ross 308) were allocated to 5 treatment groups, with 3 replicates per treatment group and 13 birds per replicate pen and all data were analyzed in a randomized complete block design. During the starter period, feed conversion ratio (FCR) was significantly (P < 0.05) decreased by only enzymes A, B and D. Moreover, FCR was significantly (P < 0.05) decreased by all enzymes in grower and entire periods. The relative weight of the breast as proportion of live weight was significantly (P < 0.05) decreased by only enzyme A. The relative weight of the abdominal fat as proportion of live weight was also significantly (P < 0.05) increased by enzyme D. Enzyme supplementation decreased viscosity of jejunal contents of chicks at day 28, but only enzymes A and D reduced significantly (P < 0.05) the viscosity of jejunum compared to control diet. In conclusion, there were similar improvements on FCR of birds fed diets with enzyme supplementation and choice preference of enzyme supplementation has to be base on its economic value

Study of possible reduction or withdrawal of vitamin premix during finisher period in floor and battery cage broiler raising systems

The effect of dietary vitamin premix withdrawal or reduction between 29 and 35, 36 and 42, and 29 and 42 days of age on broiler chicken performance and immunocompetence was evaluated. The diets were formulated based on wheat and barley, and the experiment was conducted in floor pens (experiment 1) and battery cage (experiment 2) rearing systems in 7 treatments and 4 replicates for each treatment. The results of experiment 1 showed that vitamin premix reduction and withdrawal at 29 days of age did not impair performance during the final period of broiler chicken (29 to 42 days). The results of experiment 2 showed that there were no significant differences in performance with reduction or withdrawal of vitamin premix from diets in 29 to 35 days, but in 36 to 42 days of age, performance of birds fed with a diet that has no vitamin premix (T1) was significantly lower than other treatments (P < 0.05). The results of the two experiments demonstrated that immunocompetence response was not affected by treatments in the finisher period (P > 0.05). In conclusion, the results of this study indicated that in the battery cage system, it is possible to reduce dietary vitamin premix during finisher period, but withdrawal can negatively affect performance of broiler chickens, while in the floor system, it is possible to withdraw vitamin supplements in broilers’ finisher diets.Key words: Vitamin premix, reduction, broiler, wheat, immunocompetence

Influence of different levels of n-3 supplemented (fish oil) diet on performance, carcass quality and fat status in broilers

An experiment was conducted to evaluate fish oil as n-3 fatty acids source on some performance, carcass and serum parameters in broilers. One-day old Ross strain male broiler chickens (n = 120) were randomly arranged in four dietary treatments (0, 1.5, 3 and 4.5 percent fish oil), with three replicates for each treatment. Mean live weight and feed intake at the end of starting, growing and finishing periods in fourth treatment was lower than other treatments. All treatments containing fish oil significantlydecreased feed conversion ratio compared to control treatment. There were no significant differences on percent of carcass to live weight and abdominal fat percentage to carcass weight in T2, T3 and T4, but there were significant differences between control diet and the others. Serum triglycerides, cholesterol, LDL-c and VLDL-c concentrations were significantly reduced by fish oil treatments than the control diet, but serum HDL-c concentrations were significantly increased by using of diets containingfish oil. The results of this experiment indicated that dietary  supplementation of fish oil improved feed conversion ratio, carcass quality and HDL-c concentration in serum, but it decreased serum triglycerides, cholesterol, LDL-c and VLDL-c concentrations in serum of broiler chickens

Potential probiotic of Lactobacillus johnsonii LT171 for chicken nutrition

The objective of this research was to investigate the potential probiotic of Lactobacillus johnsonii LT171. It had aggregation (60 min) and antibacterial effects against Salmonella Enteritidis, Salmonella Typhimurium and Escherichia coli O78:K80. It showed amylase and protease activity and high clear zone in culture medium containing calcium phytate; cell surface hydrophobicity, 85.21 ± 7.27%; resistance to acidic condition (pH 3 for 90 min) and bile salts (in culture medium containing 0.075% ox gall). Also it had resistance to nalidixic acid and neomycine. This research showed appropriate probiotic properties of L. johnsonii LT171 for chicken nutrition. Hence this strain can complement the characteristics of other strains in multistrain probiotics because of its high clear zone in culture medium containing calcium phytate

Hands On Biofilm! A multidisciplinary public engagement event using kombucha tea pellicle as an accessible example of biofilm

Public engagement with science has become increasingly important for the scientific community. There are many documented public engagement events that focus on aspects of microbiology, but relatively few utilise biofilms as a topic, despite their importance. Kombucha tea pellicles are easy to grow biofilms, facilitating their use within the public domain as examples of these complex communities. The aim of this work was to deliver a public engagement event that introduced visitors to general concepts about biofilm, and applications around sustainability, using kombucha. The event encouraged visitors to: build a biofilm using model clay; inoculate kombucha tea cultures using different incubation conditions, as part of a citizen science experiment to assess impact on pellicle biofilm yield; create garments and drapes on mini-mannequins using dried kombucha pellicle fabric, and demonstrate the range and importance of fermented foods (including kombucha tea), and ‘good bacteria’. Quantitative and qualitative indicators of engagement were built into the activities. More than 1200 visitors, mainly in family groups, visited the event over a 4-h period. Knowledge of biofilms was low at the beginning of the event. Participation in all activities was high. Indicators of quantitative engagement were impressive, but it was difficult to obtain qualitative evidence other than observations from the delivery team (nineteen members) because of the intensity of the event and volume of visitors. The event was clearly successful in terms of fulfilment of aims, audience engagement and enthusiasm: the embedded evaluations helped to evidence the impact and reach of the event, enabling confidence in dissemination of good practice in the enhancement of public understanding of the importance of biofilm in general, and kombucha in particular

Sub-transmission sub-station expansion planning based on bacterial foraging optimization algorithm

In recent years, significant research efforts have been devoted to the optimal planning of power systems. Substation Expansion Planning (SEP) as a sub-system of power system planning consists of finding the most economical solution with the optimal location and size of future substations and/or feeders to meet the future load demand. The large number of design variables and combination of discrete and continuous variables make the substation expansion planning a very challenging problem. So far, various methods have been presented to solve such a complicated problem. Since the Bacterial Foraging Optimization Algorithm (BFOA) yield to proper results in power system studies, and it has not been applied to SEP in sub-transmission voltage level problems yet, this paper develops a new BFO-based method to solve the Sub-Transmission Substation Expansion Planning (STSEP) problem. The technique discussed in this paper uses BFOA to simultaneously optimize the sizes and locations of both the existing and new installed substations and feeders by considering reliability constraints. To clarify the capabilities of the presented method, two test systems (a typical network and a real ones) are considered, and the results of applying GA and BFOA on these networks are compared. The simulation results demonstrate that the BFOA has the potential to find more optimal results than the other algorithm under the same conditions. Also, the fast convergence, consideration of real-world networks limitations as problem constraints, and the simplicity in applying it to real networks are the main features of the proposed method

Refreshing the public appetite for ‘good bacteria’: menus made by microbes

© 2018 Royal Society of Biology. A series of events was developed to engage audiences in discussion around the importance of microorganisms in the production of fermented foods, particularly through tasting. The events were designed to attract different audiences: families attending a science museum; families in their community space; and adults in different informal eating environments. Information was provided, alongside interactive activities where possible. Feedback was positive in that the audiences enjoyed the format, the food and the events themselves, although science itself was not always specifically mentioned. The dining experience format provided a versatile and informal opportunity for engagement between experts and non-experts, and is suggested as a valuable template for similar activities, assuming appropriate budgeting and advertising issues are addressed, alongside appropriate objective setting and effective evaluation

Computation-effective structural performance assessment using Gaussian Process-based finite element model updating and reliability analysis

Structural health monitoring data has been widely acknowledged as a significant source for evaluating the performance and health conditions of structures. However, a holistic framework that efficiently incorporates monitored data into structural identification and, in turn, provides a realistic life-cycle performance assessment of structures is yet to be established. There are different sources of uncertainty, such as structural parameters, computer model bias and measurement errors. Neglecting to account for these factors results in unreliable structural identifications, consequent financial losses, and a threat to the safety of structures and human lives. This paper proposes a new framework for structural performance assessment that integrates a comprehensive probabilistic finite element model updating approach, which deals with various structural identification uncertainties and structural reliability analysis. In this framework, Gaussian process surrogate models are replaced with a finite element model and its associate discrepancy function to provide a computationally efficient and all-round uncertainty quantification. Herein, the structural parameters that are most sensitive to measured structural dynamic characteristics are investigated and used to update the numerical model. Sequentially, the updated model is applied to compute the structural capacity with respect to loading demand to evaluate its as-is performance. The proposed framework's feasibility is investigated and validated on a large lab-scale box girder bridge in two different health states, undamaged and damaged, with the latter state representing changes in structural parameters resulted from overloading actions. The results from the box girder bridge indicate a reduced structural performance evidenced by a significant drop in the structural reliability index and an increased probability of failure in the damaged state. The results also demonstrate that the proposed methodology contributes to more reliable judgment about structural safety, which in turn enables more informed maintenance decisions to be made

The distribution of corneal thickness in rural population

To determine the distribution of corneal thickness and its associated factors in the over 5-year-old population in the north and south rural areas in Iran. In this study, samples were selected using multi -stage cluster sampling. After vision and refraction tests and the slit lamp exam, the central corneal thickness (CCT), apical corneal thickness (ACT), and the thickness at four peripheral areas of the cornea were measured using Pentacam. Of the 3851 selected samples, after applying the exclusion criteria, the analysis was done on data from 2681 people. The mean age of the participants was 36.03±18.51 years, ranging from 6 to 90 years, and 58.1 of them were female. Mean CCT and ACT were 533.87 μm (95CI: 532.05 -535.69) and 536.72 μm (95CI: 534.9 -538.54), respectively. Mean peripheral corneal thickness was 637.46 μm (95CI: 635.09 -639.83) in the superior quadrant, and 594.34 μm (95CI: 592.2 -596.47), 620.81 μm (95CI: 618.66 -622.97), and 584.55 μm (95CI: 582.18 -586.93) in the inferior, nasal, and temporal quadrants, respectively. Linear regression analysis showed significant associations between CCT and gender (P=0.001), age (P<0.001), geographical location of residence (P<0.001), the radius of corneal curvature (P<0.001), anterior chamber depth (P<0.001), and corneal volume (P<0.001). This study is one of the few studies describing the distribution of the corneal thickness in a population of over 5-year-olds using Pentacam. Gender, anterior chamber depth, and corneal radius of curvature are some of the factors associated with CCT. © 2018 Tehran University of Medical Sciences. All rights reserved