Performance, immunity, and serum biochemical parameters in broiler chickens fed diet supplemented with Zataria multiflora essential oil

Background and aims: Zataria multiflora Boiss (ZM) is a thyme-like plant reported to have immunomodulatory properties. This study was aimed to examine effects of ZM essential oil on performance, biochemical and immunological parameters in broilers. Methods: Two hundred and forty, broiler chickens were divided into 4 groups. CON considered as control group received basal diet, T100, T200 and T400 treated by basal diet supplemented with ZM 100, 200 and 400 mg/kg feed, respectively. Body weight and feed intake were recorded at 14, 28, and 42 days of age. At the end of experiment, eight broilers per group were slaughtered and carcass portion yield was calculated. Humoral immune response efficacy by injection of 5 sheep red blood cell into the pectoral muscle of birds was evaluated. Results: This study showed that supplementation of ZM promoted the weight gain in T200 as compared to other groups (P<0.05). Also, the best food conversion ratio was achieved in the same group. On the other hand, ZM supplementation in all of the doses used, did not cause significant increase in carcass portion yield (P<0.05), except for liver weight, which was significantly increased in T400. Serum biochemical analysis showed that levels of total protein, albumin and globulin were highest in T200 while the lowest were in T400; addition of ZM especially at the dose of 200 mg/kg improved immune responses in broilers (P<0.05). Conclusion: According to the results of present study, supplementing broilers diet with ZM could have favorable impact on performance and immunity

Tillage and manure effect on soil microbial biomass and respiration, and on enzyme activities

Application of liquid pig manure on soil for agricultural use increases the organic matter content and constitutes an important input of nutrients into the soil, increasing microbial activity through the direct addition of nutrients and microorganisms. The objective of this study was to determine the influence of both tillage and liquid pig manure application on soil microbial biomass, enzyme activities and microbial respiration in a meadow soil. The results obtained did not show any significant effect of tillage and manure on microbial biomass carbon (C) and nitrogen (N) nor on soil acid phosphatase activity. However, these treatments significantly increased microbial biomass P, urease, alkaline phosphatase and ammonification rates. The maximum microbial activity was observed in surface soil layer both under conventional tillage and zero-tillage. In fact, microbial respirations (CO2) of bacteria and actinomycetes were higher in the surface soil and increased with the level of manure. Tillage and manure application had no significant effect on fungal respiration but interaction between tillage and manure application significantly influenced soil urease and ammonification rates. Hence, we suggested that soil microbial biomass and enzyme activities were closely correlated to the N mineralization potential, N and C mineralization rates, total amounts of C or N, soil pH, ammonification rates and soil structural stability.Keywords: Microbial biomass, enzyme activities, respiration, pastures soi

Numerical Simulation of Shear Behaviour of Non- Persistent Joints under Low and High Normal Loads

In this paper, the effect of rock bridge surface on the shear behavior of planar non-persistent joints under low and high normal loads has been investigated using particle flow code in 2 Dimensions. PFC2d was calibrated with respect to the data obtained from experimental laboratory tests to ensure the conformity of the simulated numerical models response. The models consisting non-persistent joint were simulated and tested by shear loading under low and high normal loads. The discrete element simulations demonstrated that the failure pattern was mostly influenced by normal load, while the shear strength was linked to the failure pattern and failure mechanism. The failure patterns were found reasonably similar to the experimentally observed trends

Proposed constants for Bieniawski’s strength criterion for rocks and coal

Bieniawski’s strength criterion is one of the most widely used criteria for strength estimation of intact rocks. This criterion, however, only considers compression loading. In Bieniawski’s criterion rocks are distinguished in their properties using two parameters В and a. Selecting these parameters, through lab experiments, as representative as possible for a certain type of rock is significantly important. The quality of lab tests, the number of tests and statistical approaches used to estimate these parameters are some of the important factors, which can influence the accuracy of the estimation. Several attempts have been made by different researchers to propose these parameters for different rock types in different regions. In this paper a similar attempt was made to determine more representative constants for Bieniawski’s criterion. This work is different from past studies in that we have based our analysis on a very large number of lab experimental data gathered from the literature and some carried out for the purpose of this study. The studied data includes a wide range of rock types from soft to hard including sandstones, shales and coals. Both linear conversion and nonlinear regression models were applied to the lab data and as a result Bieniawski’s constants were proposed for each rock type. For coal, the results are presented as a function of the loading angle with respect to the coal’s fractures. The results of nonlinear models were found to be associated with higher correlation coefficients. Also a correlation between parameter В and unconfined compressive strength was proposed. The results of this study were also compared with similar work presented in the past

How orthogonal are the OBO Foundry ontologies?

<p>Abstract</p> <p>Background</p> <p>Ontologies in biomedicine facilitate information integration, data exchange, search and query of biomedical data, and other critical knowledge-intensive tasks. The OBO Foundry is a collaborative effort to establish a set of principles for ontology development with the eventual goal of creating a set of interoperable reference ontologies in the domain of biomedicine. One of the key requirements to achieve this goal is to ensure that ontology developers reuse term definitions that others have already created rather than create their own definitions, thereby making the ontologies orthogonal.</p> <p>Methods</p> <p>We used a simple lexical algorithm to analyze the extent to which the set of OBO Foundry candidate ontologies identified from September 2009 to September 2010 conforms to this vision. Specifically, we analyzed (1) the level of explicit term reuse in this set of ontologies, (2) the level of overlap, where two ontologies define similar terms independently, and (3) how the levels of reuse and overlap changed during the course of this year.</p> <p>Results</p> <p>We found that 30% of the ontologies reuse terms from other Foundry candidates and 96% of the candidate ontologies contain terms that overlap with terms from the other ontologies. We found that while term reuse increased among the ontologies between September 2009 and September 2010, the level of overlap among the ontologies remained relatively constant. Additionally, we analyzed the six ontologies announced as OBO Foundry members on March 5, 2010, and identified that the level of overlap was extremely low, but, notably, so was the level of term reuse.</p> <p>Conclusions</p> <p>We have created a prototype web application that allows OBO Foundry ontology developers to see which classes from their ontologies overlap with classes from other ontologies in the OBO Foundry (<url>http://obomap.bioontology.org</url>). From our analysis, we conclude that while the OBO Foundry has made significant progress toward orthogonality during the period of this study through increased adoption of explicit term reuse, a large amount of overlap remains among these ontologies. Furthermore, the characteristics of the identified overlap, such as the terms it comprises and its distribution among the ontologies, indicate that the achieving orthogonality will be exceptionally difficult, if not impossible.</p

Effects of various levels of organic acids and of virginiamycin on performance, blood parameters, immunoglobulins and microbial population of broiler chicks

This experiment was conducted to investigate the effects of various levels of organic acids and virginiamycin on performance, blood parameters, immunoglobulin and microbial population of broiler chickens. This trial was conducted in a completely randomized design using five treatments and four replicates. The dietary treatments included a control diet without additives, diets containing 0.05%, 0.10% and 0.15% mixtures of organic acids, and a diet containing virginiamycin as an antibiotic. Based on the results, there was no significant effect of the experimental diets on feed intake of the broilers during the starter period. However, at the end of the grower period and throughout the rearing period, feed intake was significantly improved by experimental dietary treatments. Moreover, diets including organic acids enhanced the microbial population of broiler gut. Thus, the current findings support the conclusion that organic acids improve productive traits and health status in broiler chickens.Keywords: Broiler, growth, haematology, gu