45 research outputs found
Greater numbers and sizes of muscle bundles in the breast and leg muscles of broilers compared to layer chickens
Meat-type (broiler) and egg-type (layer) chickens were bred by intensive selection over the years, resulting in more numbers and larger sizes of myofibers. Although the characteristics are important parameters in muscle growth and meat quality, muscle bundle characteristics have not been studied in poultry. Therefore, this study aimed to compare the histological characteristics of myofibers and muscle bundles in muscles between male broiler (Ross broiler breed) chickens and layer (Hy-Line) chickens. Chicken muscles, pectoralis major (PM) and gastrocnemius (GM), were sampled at the age of 49 days and stained to analyze histological characteristics. Expectedly, body weights (BWs) and weights of PM and GM muscles in 49-day-old broilers were significantly heavier than those in layers. Within PM, broilers exhibited greater number and cross-sectional area (CSA) of myofibers than layers (3.3- and 3.3-fold, respectively). The total number and CSA of PM muscle bundles were approximately 1.5 and 6.6 times greater, respectively, in broilers than layers. Moreover, broilers exhibited 2 times greater number of myofibers per bundle of PM muscle than layers. Within GM, myofiber number and CSA were 2.3- and 2.4-fold greater, respectively, in broilers than layers. In addition, the total number of muscle bundles and bundle CSA were 2.5- and 2.1-fold greater, respectively, in broilers than in the layers. The novel findings of the current study provide evidence that greater muscle mass of broilers occurs by both hyperplasia and hypertrophy of muscle bundles and myofibers
Effects of full litter reuse with or without chemical amendment on measures of welfare and performance on three Australian broiler farms
There are pressures on some sectors of the Australian broiler industry to reuse poultry litter for multiple batches of chickens. We investigated the effects of reused litter on bird performance, welfare, litter pH and moisture, and air ammonia concentrations on three commercial farms (A, B, and C) across NSW, Australia. On each farm, the litter inside six sheds was assigned to one of three treatments: 1) a full cleanout replenished with new litter (NL); 2) litter reuse in the entire shed following heaping and turning (RL); and 3) RL plus the addition of a commercial acidifying litter amendment (RL+A). In the RL and RL+A sheds, chicks were placed directly on reused litter. Bird performance, welfare, and litter measurements were made on days 0, 7, 14, and 35. Feed conversion ratios (adjusted to 2.45kg) on a whole farm basis were 1.868, 1.839 and 1.920 for farms A, B, and C, respectively. Day 35 weights were highest on RL on all 3 farms but the effect of litter treatment on mortality varied between farms, with some indication that placing chicks on reused litter less than 3 days after re-spreading increased early mortality. On all three farms, welfare measures provided no evidence of sustained reduction in welfare status of birds on reused litter, nor any clear benefits or disadvantages of litter amendment. Litter moisture content and pH varied significantly with treatment and time on all farms. On the reused litter treatments, moisture content increased steadily on all farms between placement and day 35, with no effect of litter amendment. The litter amendment also failed to lower the pH of the reused litter at any time; however, it did appear to have a reducing effect on air ammonia concentrations relative to the RL treatment on farms B and C. In conclusion, bird performance and welfare can be maintained on reused litter if managed properly
Real-time surveillance and response system for Ebola and other emerging infections
ObjectiveWe will describe a real-time mobile surveillance and casemanagement system designed to organize data collected bymultiple officers about cases and their contacts. We will discuss thissurveillance system and its application for Ebola and other infectiousdiseases in the Democratic Republic of the Congo (DRC) and othersimilar settings. We will review the technology, results, challenges,lessons-learned, and applicability to other contexts.IntroductionImproving surveillance and response is a critical component ofthe Global Health Security Agenda. While it is impossible to predictwhere the next Ebola outbreak will occur, it is very likely that anotheroutbreak will occur in the DRC. Of the 20 known outbreaks, 7 haveoccurred in the DRC, one as recently as 2014. To rapidly detectand respond to an Ebola outbreak, we sought to develop a real-timesurveillance and response system for use in DRC and similar settings.RTI International developed Coconut Surveillance mobile software,which is currently used for real-time malaria surveillance andresponse in Zanzibar, Africa, where malaria elimination efforts areunderway. We took this system and adapted it for Ebola as a possibletool for surveillance and response to Ebola and other (re)emergingdiseases. Plans include pilot testing functionality at clinical sites inDRC, where surveillance infrastructure is limited at the local level.Coconut Surveillance is a mobile disease surveillance and rapidresponse system currently used for malaria elimination activities.It receives suspected positive case alerts from the field via mobilephones and uses mobile software to guide surveillance officersthrough a follow-up process. Coconut Surveillance runs on Androidmobile devices that are used to coordinate work in the field as well asprovide decision support during data collection and case management.In addition to standard case information, the GPS coordinates ofthe case’s household are captured as well as malaria status of allhousehold members. Data are collected and accessed off-line, and aresynchronized with a shared database when Internet connectivity isavailable. This tool has been used successfully in Zanzibar for morethan three years and has been recognized as one of the most advancedapplications of its kind.MethodsWe adapted the Coconut Surveillance system for Ebolasurveillance and response, and expanded the system for use with othercommunicable diseases. With a near real-time outbreak detectionsystem for Ebola, we may reduce the response time and contain anoutbreak faster. Using a cloud-based data repository, the modifiedCoconut System, known as Coconut Plus, also has the added value ofcase and case-contacts specific information sharing in real-time withthe national, provincial, and district level public health authorities,who would have convenient and secure access to case and contactinformation via the Internet. The software modifications to theCoconut System have been informed by testing and stakeholderfeedback.ResultsWe have developed Coconut Plus around the Coconut softwarearchitecture, which allows the team to quickly develop specificworkflows and applications, such as contact tracing, on top of a solidand well-supported base. Additionally, the adaptation was structuredto accommodate the build-out of multiple diseases, and is uniquelyhelpful for diseases that require tracking many contacts. We weregranted access in DRC to test interoperability with DHIS 2, the mostwidely used health information system software in Ebola effectedcountries. Coconut Plus is now using the DHIS 2 organizationalhierarchy definition, which means that organizational hierarchy(including information on administrative units and health carefacilities) can be exported directly from DHIS 2 to Coconut Plus.Stakeholder feedback on the usability and feasibility of the adaptedsystem has been enthusiastic, and stressed the need for additionalresources to make a pilot successful, including mobile phones andimproved mobility of surveillance staff in the field. The followingscreencast provides an overview of the application: https://www.youtube.com/watch?v=jjLT3pLLW-UConclusionsCoconut Surveillance Plus solves an absence of a real-time mobiledecision support disease surveillance and response system that can beused for Ebola and other infectious diseases in countries with limitedsurveillance infrastructure. More broadly, this system could also beused for many communicable diseases that require contact tracing andan urgent outbreak response in environments that require rapid scaleup of a distributed surveillance, rapid response, and case managementsystem
Effects of Broiler Litter Reuse in a Commercial Australian Production System
There is pressure on the Australian broiler industry to reuse poultry litter for multiple batches of chickens. We investigated the effects of reused litter on bird performance, welfare, litter pH and moisture, and air ammonia concentrations on a commercial farm in Sydney. The litter inside six sheds was assigned to one of three treatments: 1) full cleanout followed by fresh pine shavings (CNT); 2) litter reuse following heaping and turning (HT); and 3) HT plus the addition of a commercial acidifying litter amendment (HT+A)
Interrelations between the Microbiotas in the Litter and in the Intestines of Commercial Broiler Chickens â–¿
The intestinal microbiota of broiler chickens and the microbiota in the litter have been well studied, but the interactions between these two microbiotas remain to be determined. Therefore, we examined their reciprocal effects by analyzing the intestinal microbiotas of broilers reared on fresh pine shavings versus reused litter, as well as the litter microbiota over a 6-week cycle. Composite ileal mucosal and cecal luminal samples from birds (n = 10) reared with both litter conditions (fresh versus reused) were collected at 7, 14, 21, and 42 days of age. Litter samples were also collected at days 7, 14, 21, and 42. The microbiotas were profiled and compared within sample types based on litter condition using PCR and denaturing gradient gel electrophoresis (PCR-DGGE). The microbiotas were further analyzed using 16S rRNA gene clone libraries constructed from microbiota DNA extracted from both chick intestinal and litter samples collected at day 7. Results showed significant reciprocal effects between the microbiotas present in the litter and those in the intestines of broilers. Fresh litter had more environmental bacteria, while reused litter contained more bacteria of intestinal origin. Lactobacillus spp. dominated the ileal mucosal microbiota of fresh-litter chicks, while a group of bacteria yet to be classified within Clostridiales dominated in the ileal mucosal microbiota in the reused-litter chicks. The Litter condition (fresh versus reused) seemed to have a more profound impact on the ileal microbiota than on the cecal microbiota. The data suggest that the influence of fresh litter on ileal microbiota decreased as broilers grew, compared with temporal changes observed under reused-litter rearing conditions
Impacts of litter heaping and turning +/- litter amendment on broiler performance and welfare
As poultry meat consumption trends continue to increase worldwide, maximizing production efficiency continues to be the forefront focus among producers and industry leaders. Multi-batch litter has become an increasingly important and relatively common practice worldwide in poultry production. However, unlike in the United 8tates and Brazil, the majority of bedding material in Australia is used in single-batch litter production (Runge et al., 2007). Bedding material for commercial broiler sheds generally consists of whatever absorbent material is regionally available, and in Australia this consists of wood shavings, rice hulls, sawdust, and, to a lesser extent, chopped wheat straw (Robins and Phillips, 2011). At a target depth of 50 mm and an estimated cost of 0.05AUD/bird or more depending on stocking density. Any future scarcity of bedding materials would result in higher production costs. Multi-batch litter would not only reduce input costs for Australian broiler producers, but also promote resource availability and sustainability within a growing industry
Development of Methods for Recovery and Quantitation of Viral Nucleic Acids from Broiler Litter
We investigated the development of standardised methods of extraction and quantitation of viral nucleic acids from broiler litter. To detect and quantify virus we used fully quantitative Taqman® qPCR assays with plasmid-based standard curves to quantify Marek's disease virus (MDV, dsDNA), infectious laryngotracheitis virus (ILTV, dsDNA), Fowl adenovirus (FadV, dsDNA), chicken anaemia virus (CAV, ssDNA) and infectious bursal disease virus (IBDV, dsRNA). A series of experiments examined the effects of litter washing, blending, bead beating, and removal of inhibitors using polyvinylpolypyrrolidone (PVPP). To evaluate the qPCR assays and the DNA extraction techniques we monitored the recovery of fixed amounts of virus added to litter samples. The three litter types used were hardwood shavings, softwood (pine) shavings and rice hulls. Hardwood shavings were shown to contain high levels of PCR inhibitors but these could be neutralised by PVPP. Detectable virus recovery was good for IBDV and CAV, but low for the dsDNA viruses ILTV and MDV. The third dsDNA virus, FAdv, was unable to be detected. The four detectable viruses were detectable in all fractions of material (retentate after filtration, and in both the pellet and supernatant fractions following centrifugation of the filtrate) with highest concentrations in the pellet. The results indicate that a method based on washing samples with buffer containing 0.15% Tween-80 followed by bead beating and PVPP treatment would enable detection of most DNA and RNA viruses from litter with the greatest concentration of virus found in the pellet fraction after centrifugation. Work is ongoing to resolve the low recovery rate of dsDNA viruses and to simplify the litter processing and DNA extraction further
Effects of Various Additives to Reused Broiler Litter on Litter Ammonia Production, Chicken Welfare and Performance
We investigated the effects of adding alum, sodium bisulphate, bentonite, zeolite and NaturClean CSM® at 3.2, 3.2, 13, 13 and 0.9 % by weight respectively to reused litter on moisture content, pH, ammonia production, bird liveweight and conditions linked to welfare including scores for footpad dermatitis, hock burn, breast burn and breast feathering. Treatments, including no amendment, were applied to four pens each 2.25 m² with half the pens having 20% additional water added. Nineteen broiler chicks were reared in each pen up to day 42 with sampling of the litter and birds at various intervals. Litter moisture content of 31% on day 0, reduced to approximately 21% on days 7 and 14 before increasing to a value of 53% on day 42. All litter amendments except NaturClean CSM® reduced ammonia production with the greatest reductions seen with alum and sodium bisulphite on days 7 and 14. Amendments worked similarly in litter with or without water addition. There were no significant effects of litter amendment on bird weights or measures of welfare with welfare measures generally worsening with time and with initial addition of water. Ranking of reused litter treatments from 1 to 6 (best to worst) for each welfare measure, followed by the averaging of those rankings, provided mean rankings of 1.75, 2.25, 3, 3.75, 4.75 and 5.5 respectively for reused litter without amendment, bentonite, alum, sodium bisulphite, NaturClean CSM® and zeolite treatments. Both acidifying and adsorbent litter additives have potential to significantly reduce ammonia concentrations on reused litter. Further work is required to determine optimum inclusion rates and more clearly identify effects on welfare and performance