Comparing the Effects of Conventional and Pastured Poultry Production Systems on the Stress Levels of Broilers

Abstract The objective of this study was to measure stress levels in broilers raised on a pasture production system (PPS) and a conventional production system (CPS) by evaluating lymphoid organ weights, white blood cell profiles (WBCP), total white blood cell counts (TWBC), and heterophil to lymphocyte ratios (HLR). Broilers were brooded indoors for 3 weeks then divided into 2 groups; one placed on pasture while the other remained indoors. Blood was collected at weeks 3, 5, and 7 via brachial venipuncture. After 49 days, birds were slaughtered and lymphoid organs harvested. Results showed no differences between treatments for lymphoid organs, TWBC, or WBCP. Eosinophils were higher (P \u3c 0.05) in CPS (333.33) compared to PPS birds (148.00) at week 5. The HLR was lower (P \u3c 0.05) in PPS broilers at week 5 (0.40) than weeks 3 (0.44) and 7 (0.43). The PPS broilers experienced less stress overall than CPS birds. Keywords: Conventional Production System, Broilers, Pasture Production System, Stres

Evaluating the Economic Feasibility of Producing Broilers on Pasture and in a Conventional Production System

The demand for pasture raised poultry is increasing because of the perception that it is healthier and tastier than conventionally raised poultry. In order to meet this demand, some producers are considering switching from the conventional to the pasture system to take advantage of this niche market. Therefore, the objective of the study was to determine the economic viability of rearing broilers in a pastured poultry system (PPS) versus a conventional poultry system (CPS). Each of these systems was replicated three times with 60 birds per treatment in a study lasting seven weeks. Data were collected on costs of inputs, and others estimated. The mean net returns for PPS and CPS were, respectively, $56.44 and -$92.02. The break-even prices were, respectively, $10.89 for PPS and$11.87 for CPS. Also, the benefit/cost ratio was 1.103 for PPS and 0.845 for CPS. The paired t-test for the benefit/cost ratios indicated a significant difference (p< 0.05) between PPS and CPS. PPS was deemed more feasible than CPS. Hence, it was recommended that the former system is more appropriate for small and limited resource producers, and that technical assistance should be provided to them regarding PPS. Keywords: Pastured poultry, Conventional poultry, Economic feasibility, Broiler

Characterization, Comparative Genomics and Genome Mining for Antibiotics and Secondary Metabolite of two Actinomycetales isolates

Actinomycetes are ubiquitous Gram (+) bacteria commonly found to have high G+C content and best known for their metabolic by-products and novel enzymes [1]. Isolates CCMMD2014 & MRMD2014 were co-cultured from soil impacted by a rusty fire hydrant in Woods Hole, MA. The Streptomyces sp. and Curtobacterium sp. isolates were identified by marker genes for 16S rRNA, rpoB, xylose isomerase, tryptophan synthase beta chain and Cytochrome P450 monooxygenase. Both isolates showed lactic acid fermentation and urease activity. The co-isolates were separated by selective culturing with antibiotics. In addition, whole genome sequencing revealed distinct inherent metabolic pathways in each culture that allowed for mutually exclusive selective culture conditions. Assembly was done using HGAP3 with Celera8 assembler using SMRT portal [2,3]. Annotation was done using the RAST server [4], with 7540 and 3969 CDS for Streptomyces sp. and Curtobacterium sp. respectively being revealed by AMIGene and BASys [5,6]. Subsequently, antiSMASH [7], was used to predict 52 and 26 secondary metabolite biosynthetic clusters that included genes for lantipeptides, terpenes, siderophores, polyketide synthases type I and II, bacteriocin and nonribosomal peptide synthase genes for Streptomyces sp. and Curtobacterium sp. respectively. The isolates have genes of potentially beneficial traits that could help study, among others, the role of fimbrial adhesins and iron in biofilm formation and investigation on natural products

Male Competition Reverses Female Preference For Male Chemical Cues

Females must choose among potential mates with different phenotypes in a variety of social contexts. Many male traits are inherent and unchanging, but others are labile to social context. Competition, for example, can cause physiological changes that reflect recent wins and losses that fluctuate throughout time. We may expect females to respond differently to males depending on the outcome of their most recent fight. In Bolitotherus cornutus (forked fungus beetles), males compete for access to females, but copulation requires female cooperation. In this study, we use behavioral trials to determine whether females use chemical cues to differentiate between males and whether the outcome of recent male competition alters female preference. We measured female association time with chemical cues of two size‐matched males both before and after male–male competition. Females in our study preferred to associate with future losers before males interacted, but changed their preference for realized winners following male competitive interactions. Our study provides the first evidence of change in female preference based solely on the outcome of male–male competition

Gate voltage dependent Rashba spin splitting in hole transverse magnetic focussing

Magnetic focussing of charge carriers in two-dimensional systems provides a solid state version of a mass spectrometer. In the presence of a spin-orbit interaction, the first focussing peak splits into two spin dependent peaks, allowing focussing to be used to measure spin polarisation and the strength of the spin-orbit interaction. In hole systems, the k^3 dependence of the Rashba spin-orbit term allows the spatial separation of spins to be changed in-situ using a voltage applied to an overall top gate. Here we demonstrate that this can be used to control the splitting of the magnetic focussing peaks. Additionally, we compare the focussing peak splitting to that predicted by Shubnikov-de Haas oscillations and k.p bandstructure calculations. We find that the focussing peak splitting is consistently larger than expected, suggesting further work is needed on understanding spin dependent magnetic focussing

Spin polarisation and spin dependent scattering of holes in transverse magnetic focussing

In 2D systems with a spin-orbit interaction, magnetic focussing can be used to create a spatial separation of particles with different spin. Here we measure hole magnetic focussing for two different magnitudes of the Rashba spin-orbit interaction. We find that when the Rashba spin-orbit magnitude is large there is significant attenuation of one of the focussing peaks, which is conventionally associated with a change in the spin polarisation. We instead show that in hole systems with a $k^3$ spin-orbit interaction, this peak suppression is due to a change in the scattering of one spin state, not a change in spin polarisation. We also show that the change in scattering length extracted from magnetic focussing is consistent with results obtained from measurements of Shubnikov-de Haas oscillations. This result suggests that scattering must be considered when relating focussing peak amplitude to spin polarisation in hole system

Probing Fermi surface shifts with spin resolved transverse magnetic focussing

Transverse magnetic focussing is the solid state equivalent of a mass spectrometer. It is unique among 2D measurement techniques as it is able to measure a well defined section of the Fermi surface, making it possible to detect changes that would be averaged out over the whole Fermi surface. Here, we utilise this unique property to probe non-adiabatic spin dynamics and spin dependent scattering of holes. We combine spin-resolved magnetic focussing with an additional independent in-plane magnetic field and observe a change in focussing peak amplitude that is not symmetric with respect to the field direction (i.e. $+B_{\parallel} \neq -B_{\parallel}$), and is extremely sensitive to the magnitude of the in-plane magnetic field. We show that the magnetic focussing signal is extremely sensitive to small changes in the Fermi velocity, which can be used to detect small shifts in the Fermi surface caused by an in-plane magnetic field. We also find that focussing can be used to detect the proximity between spin-split Fermi surfaces, which cause non-adiabatic spin dynamics

Meeting report : 1st international functional metagenomics workshop May 7–8, 2012, St. Jacobs, Ontario, Canada

This report summarizes the events of the 1st International Functional Metagenomics Workshop. The workshop was held on May 7 and 8 in St. Jacobs, Ontario, Canada and was focused on building a core international functional metagenomics community, exploring strategic research areas, and identifying opportunities for future collaboration and funding. The workshop was initiated by researchers at the University of Waterloo with support from the Ontario Genomics Institute (OGI), Natural Sciences and Engineering Research Council of Canada (NSERC) and the University of Waterloo

Complete Genome Sequence of Curtobacterium sp. Strain MR_MD2014, Isolated from Topsoil in Woods Hole, Massachusetts

Here, we present the 3,443,800-bp complete genome sequence of Curtobacterium sp. strain MR_MD2014 (phylum Actinobacteria). This strain was isolated from soil in Woods Hole, MA, as part of the 2014 Microbial Diversity Summer Program at the Marine Biological Laboratory in Woods Hole, MA