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Fecal Microbiota Transplant From Highly Feed Efficient Donors Affects Cecal Physiology and Microbiota in Low- and High-Feed Efficient Chickens
Get PDFPublication history: Accepted - 25 June 2019; Published online - 9 July 2019Fecal microbiota transplants (FMT) may be used to improve chicken’s feed efficiency
(FE) via modulation of the intestinal microbiota and microbe-host signaling. This study
investigated the effect of the administration of FMT from highly feed efficient donors early
in life on the jejunal and cecal microbiota, visceral organ size, intestinal morphology,
permeability, and expression of genes for nutrient transporters, barrier function and
innate immune response in chickens of diverging residual feed intake (RFI; a metric
for FE). Chicks (n = 110) were inoculated with the FMT or control transplant (CT) on
1, 6, and 9 days posthatch (dph), from which 56 chickens were selected on 30 dph
as the extremes in RFI, resulting in 15 low and 13 high RFI chickens receiving the
FMT and 14 low and 14 high RFI chickens receiving the CT. RFI rank and FMT only
caused tendencies for alterations in the jejunal microbiota and only one unclassified
Lachnospiraceae genus in cecal digesta was indicative of high RFI. By contrast, the
FMT caused clear differences in the short-chain fatty acid (SCFA) profile in the crop
and cecal microbiota composition compared to the CT, which indicated alterations
in amylolytic, pullulanolytic and hemicellulolytic bacteria such as Lactobacillus, Dorea,
and Ruminococcus. Moreover, the FMT caused alterations in intestinal development
as indicated by the longer duodenum and shallower crypts in the ceca. From the
observed RFI-associated variation, energy-saving mechanisms and moderation of the
mucosal immune response were indicated by higher jejunal permeability, shorter villi
in the ileum, and enhanced cecal expression of the anti-inflammatory cytokine IL10 in
low RFI chickens. Relationships obtained from supervised multigroup data integration
support that certain bacteria, including Ruminococcocaceae-, Lactobacillus-, and
unclassified Clostridiales-phylotypes, and SCFA in jejunal and cecal digesta modulated
expression levels of cytokines, tight-junction protein OCLN and nutrient transporters
for glucose and SCFA uptake. In conclusion, results suggest that the intestine only
Frontiers in Microbiology | www.frontiersin.org 1 July 2019 | Volume 10 | Article 1576
fmicb-10-01576 July 5, 2019 Time: 15:15 # 2
Metzler-Zebeli et al. Fecal Microbiota Transplant and Gut Functions
played a moderate role for the RFI-associated variation of the present low and high
RFI phenotypes, whereas modulating the early microbial colonization resulted in longlasting changes in bacterial taxonomic and metabolite composition as well as in host
intestinal development.This project (ECO-FCE) has received funding from the European Union’s Seventh Framework Programme for research, technological development, and demonstration under Grant Agreement No. 311794
Nitrogen use efficiency and nitrous oxide emissions from five UK fertilised grasslands
Get PDFPublication History: Accepted - 8th January 2019; Published Online - 9th January 2019; Published - 15th April 2019Intensification of grasslands is necessary to meet the increasing demand of livestock products. The application of nitrogen (N) on grasslands affects the N balance therefore the nitrogen use efficiency (NUE). Emissions of nitrous oxide (N2O) are produced due to N fertilisation and low NUE. These emissions depend on the type and rates of N applied. In this study we have compiled data from 5 UK N fertilised grassland sites (Crichton, Drayton, North Wyke, Hillsborough and Pwllpeiran) covering a range of soil types and climates. The experiments evaluated the effect of increasing rates of inorganic N fertiliser provided as ammonium nitrate (AN) or calcium ammonium nitrate (CAN). The following fertiliser strategies were also explored for a rate of 320 kg N ha−1: using the nitrification inhibitor dicyandiamide (DCD), changing to urea as an N source and splitting fertiliser applications. We measured N2O emissions for a full year in each experiment, as well as soil mineral N, climate data, pasture yield and N offtake. N2O emissions were greater at Crichton and North Wyke whereas Drayton, Hillsborough and Pwllpeiran had the smallest emissions. The resulting average emission factor (EF) of 1.12% total N applied showed a range of values for all the sites between 0.6 and 2.08%. NUE depended on the site and for an application rate of 320 kg N ha−1, N surplus was on average higher than 80 kg N ha−1, which is proposed as a maximum by the EU Nitrogen Expert Panel. N2O emissions tended to be lower when urea was applied instead of AN or CAN, and were particularly reduced when using urea with DCD. Finally, correlations between the factors studied showed that total N input was related to Nofftake and Nexcess; while cumulative emissions and EF were related to yield scaled emissions
Editorial: Bovine Tuberculosis—International Perspectives on Epidemiology and Management
Get PDFPublication history: Accepted - 6 June 2019; Published online - 25 June 2019Bovine tuberculosis (bTB) remains a prominent zoonotic pathogen on the world stage, with significant impacts on animal and human health, and economic well-being. Eradication is hampered by a complex epidemiology, which in many countries involves wildlife hosts. Indeed, despite advances in understanding gleaned from national programs of bTB eradication, much of our understanding of transmission mechanisms, diagnostics, control, and multi-host infection systems remains opaque.
In this collection of Frontiers in Veterinary Science, as editors, we felt these limitations could best be addressed by adopting an international perspective. Localism understandably focuses on the fine details of problems at hand, but can perhaps overlook issues that only become apparent when compared to the experiences of others.
Below we summarize the papers published in this truly international collection, and highlight some themes. We trust readers will find these articles as stimulating to read as they were to edit
Investigation of Enteric Viruses Associated With Runting and Stunting in Day-Old Chicks and Older Broilers in Southwest Nigeria
Get PDFPublication history: Accepted - 2 July 2019; Published - 16 July 2019Enteric viruses are known to have significant economic impact on poultry, especially
broiler chicken flocks, because of production losses attributable to poor feed conversion
and weight gain. To sustain the Nigerian poultry industry that contributes significantly to
the livestock sector of the economy, there is a need to investigate commercial broiler
flocks in the country for the presence of enteric viruses causing runting and stunting,
growth retardation, and hatchery diseases. Gut contents were collected from 158
day-old and six 14-week old runted/stunted broiler chickens in commercial farms (ten)
and hatcheries (six) located in Southwest Nigeria. The samples were examined for the
presence of chicken astrovirus (CAstV), avian nephritis virus (ANV), avian rotavirus (AvRV),
chicken parvovirus (ChPV), and turkey astroviruses (TAstV-1 and−2) by polymerase chain
reaction (PCR) and reverse transcriptase-PCR (RT-PCR) whereas avian reovirus (ARV)
and fowl adenovirus (FAdV) by virus isolation (VI), RT-PCR, and PCR. While CAstV was
detected in all the birds (100%), sporadic detection of ANV (5%), and ChPV (5%) was
observed in day-old and/or older birds. Four isolates were obtained by VI with one isolate
being ARV positive and other three FAdV positive by RT-PCR and PCR, respectively.
These findings strongly suggest CAstV as a major cause of runting and stunting as
well as hatchery condemnations in commercial broilers in Southwest Nigeria, although
co-infections with ANV, FAdV, ARV, and ChPV cannot be ruled out. In addition, the
possible vertical and horizontal transmissions of these viruses are discussed
Interspecific visitation of cattle and badgers to fomites: A transmission risk for bovine tuberculosis?
Get PDFPublication history: Accepted - 23 April 2019In Great Britain and Ireland, badgers (Meles meles ) are a wildlife reservoir of Mycobacterium bovis and implicated in bovine tuberculosis transmission to domestic cattle. The route of disease transmission is unknown with direct, so‐called “nose‐to‐nose,” contact between hosts being extremely rare. Camera traps were deployed for 64,464 hr on 34 farms to quantify cattle and badger visitation rates in space and time at six farm locations. Badger presence never coincided with cattle presence at the same time, with badger and cattle detection at the same location but at different times being negatively correlated. Badgers were never recorded within farmyards during the present study. Badgers utilized cattle water troughs in fields, but detections were infrequent (equivalent to one badger observed drinking every 87 days). Cattle presence at badger‐associated locations, for example, setts and latrines, were three times more frequent than badger presence at cattle‐associated locations, for example, water troughs. Preventing cattle access to badger setts and latrines and restricting badger access to cattle water troughs may potentially reduce interspecific bTB transmission through reduced indirect contact.This study was part of a PhD studentship funded by the Department of Agriculture, Environment and Rural Affairs (DAERA)
Pectobacterium and Dickeya species detected in vegetables in Northern Ireland
Get PDFPublication history: Accepted - 22 January 2019; Published online - 7 February 2019.Destructive soft rot Pectobacteriaceae affect a number of vegetable crops and cause high economic loses in the field and storage. The diversity of Pectobacterium and Dickeya causing soft rot of vegetables in Northern Ireland is unknown. This study provides details of Pectobacterium and Dickeya spp. detected in vegetables from several locations in Northern Ireland in the years 2015–2017. Soft rot Pectobacteriaceae were identified based on DNA sequences. Thirty one strains were selected for further phylogenetic analysis based on the recA gene region. Results from the testing of over 3456 potato samples for plant health statutory purposes in years 2005–2017 demonstrated that Dickeya spp. is not the major pathogen causing soft rot or blackleg in Northern Ireland. The most predominant species causing soft rot of vegetables in Northern Ireland were Pectobacterium atrosepticum and Pectobacterium carotovorum subsp. carotovorum. Pectobacterium atrosepticum was also detected on hosts other than potato. Testing of bacteria isolated from carrots led to the detection of P. carotovorum and Dickeya sp. This is the first study to provide knowledge about Pectobacterium and Dickeya spp. diversity causing soft rot of vegetables in Northern Ireland confirmed by real-time PCR and DNA sequences. This is also the first report of the detection of D. aquatica from a source other than water
Effect of overlaying rubber on fully slatted concrete floors on hoof health and lying postures in finishing dairy-origin bulls offered two contrasting diets
Get PDFPublication history: Accepted - 1 October 2019; Published - 7 December 2020.Fully slatted concrete floors are labour-efficient, cost-effective and thus common in beef cattle housing. However, the welfare of
cattle accommodated on them has been questioned. The objective of this study was to evaluate the effect of floor and diet on
hoof health and lying behaviours of housed dairy-origin bulls, from a mean age of 8 months to slaughter at 15.5 months old.
Forty-eight bulls, which had a mean initial live weight of 212 (SD = 23.7) kg, were allocated to one of four treatments, which
consisted of two floors and two diets arranged in a 2 × 2 factorial design. The floors evaluated were a fully slatted concrete
floor and a fully slatted concrete floor overlaid with rubber, while the diets offered were either a high concentrate diet or a
grass-silage-based diet supplemented with concentrates. The mean total duration of the study was 216 days. Floor had no
significant effect on claw measurements measured on day 62 or 139. However, bulls accommodated on slats overlaid with rubber
had a tendency to have a higher front toe length measured pre-slaughter than those accommodated on concrete slats
( P = 0.063). Floor had no significant effect on the net growth of toes or heels during the duration of the study. The number of
bruises ( P < 0.01) and the bruising score ( P < 0.05) were significantly higher on day 62 in bulls accommodated on fully slatted
concrete floors than on concrete slats overlaid with rubber, but there was no significant effect of floor on these parameters on
day 139 or at the measurement taken pre-slaughter. There was a tendency for bulls accommodated on concrete slats to have a
higher probability of having sole bruising at the end of the experiment than those accommodated on slats overlaid with
rubber ( P = 0.052). Diet had no significant effect on toe length or heel height, number of bruises, or overall bruising score at any
time point of the study. There was little evidence in the current study to suggest that bulls lying on fully slatted concrete floors
could not express lying postures similar to those on concrete slats overlaid with rubber.DAERA (Department of Agriculture, Environment and Rural
Affairs in Northern Ireland.
Is There a Relationship Between Bovine Tuberculosis (bTB) Herd Breakdown Risk and Mycobacterium avium subsp. paratuberculosis Status? An Investigation in bTB Chronically and Non-chronically Infected Herds
Get PDFPublication history: Accepted - 23 January 2019; Published - 14 February 2019.Background: Bovine tuberculosis (bTB; Mycobacterium bovis) remains a significant
problem in a number of countries, and is often found where M. avium subsp. paratuberculosis (MAP) is also present. In the United Kingdom, bTB has been difficult
to eradicate despite long-term efforts. Co-infection has been proposed as one partial
mechanism thwarting eradication.
Methods: A retrospective case-control study of 4,500 cattle herds in Northern Ireland,
where serological testing of cattle for MAP, was undertaken (2004–2015). Blood samples
were ELISA tested for MAP; infection of M. bovis was identified in herds by the comparative tuberculin test (CTT) and through post-mortem evidence of infection. Case-herds were those experiencing a confirmed bTB breakdown; control-herds were not experiencing a breakdown episode at the time of MAP testing. A second model included additional testing data of feces samples (culture and PCR results) to better inform herd MAP status. Multi-level hierarchical models were developed, controlling for selected confounders. A sensitivity analysis of the effect of MAP sample numbers per event and the prior timing of tuberculin-testing was undertaken.
Results: 45.2% (n = 250) of case observations and 36.0% (3,480) of control observations were positive to MAP by ELISA (45.8% and 36.4% when including ancillary
fecal testing, respectively). Controlling for known confounders, the adjusted odds ratio
(aOR) for this association was 1.339 (95%CI:1.085–1.652; including ancillary data aOR:1.356;95%CI:1.099–1.673). The size-effect of the association increased with the
increasing number of samples per event used to assign herd MAP status (aOR:1.883 at
>2 samples, to aOR:3.863 at >10 samples), however the estimated CI increased as N
decreased. 41.7% of observations from chronic herds were MAP serology-positive and
32.2% from bTB free herds were MAP positive (aOR: 1.170; 95%ci: 0.481–2.849).
Discussion: Cattle herds experiencing a bTB breakdown were associated with
increased risk of having a positive MAP status. Chronic herds tended to exhibit higher
risk of a positive MAP status than bTB free herds, however there was less support for this association when controlling for repeated measures and confounding. MAP co-infection may be playing a role in the success of bTB eradiation schemes, however further studies are required to understand the mechanisms and to definitively establish causation
Identification and epidemiological analysis of Perostrongylus falciformis infestation in Irish badgers
Get PDFPublication history: Accepted - 24 June 2019; Published Online - 9 July 2019Background: The lungworm, Perostrongylus falciformis (fomerly known as Aelurostrongylus falciformis) has been
identified in badgers (Meles meles) in Britain, the Russian Federation, Italy, Norway, Poland, Ukraine, Bosnia Herzegovina
and Romania, while Aelurostrongylus pridhami has been reported from badgers in Spain.
Results: Pulmonary tissue from 1580 Irish badgers was examined and an estimated prevalence of 32.09% (95% CI:
29.79–34.45%) of this parasite was detected. Confirmation of its occurrence was made by PCR analysis on a subset of
the population.
Conclusion: Infestation was widely distributed throughout the Republic of Ireland, with a trend towards higher
infestation risk in western versus eastern counties. In addition males were at a higher risk of infestation than females
and juveniles were at a significantly higher risk than adult badgers
Feed Restriction Modifies Intestinal Microbiota-Host Mucosal Networking in Chickens Divergent in Residual Feed Intake
Get PDFPublication history: Accepted online - 8 January 2019; Published online - 29 January 2019.Differences in chickens’ feed intake may be the underlying factor influencing
feed-efficiency (FE)-associated variation in intestinal microbiota and physiology.
In chickens eating the same amount of feed, quantitative feed restriction may
create similar intestinal conditions and help clarify this cause-and-effect relationship.
This study investigated the effect of ad libitum versus restrictive feeding (85% of ad
libitum) on ileal and cecal microbiota, concentrations of short-chain fatty acids, visceral
organ size, intestinal morphology, permeability, and expression of genes related
to nutrient uptake, barrier function, and innate immune response in broiler
chickens with divergent residual feed intake (RFI; metric for FE). On day 30 posthatch,
28 low-RFI (good FE) and 29 high-RFI (poor FE) chickens across both feedinglevel
groups (n 112) were selected. Supervised multigroup data integration and
relevance network analyses showed that especially Lactobacillus (negative) in ileal digesta,
Turicibacter (positive) in cecal digesta, and Enterobacteriaceae (positive) in
both intestinal segments depended on chicken’s feed intake, whereas the level of
Anaerotruncus in cecal digesta was most discriminative for high RFI. Moreover, shallower
crypts and fewer goblet cells in ceca indicated host-related energy-saving
mechanisms with low RFI, whereas greater tissue resistance suggested a stronger jejunal
barrier function in low-RFI chickens. Values corresponding to feed intake
level RFI interactions indicated larger pancreas and lower levels of ileal and cecal
short-chain fatty acids in restrictively fed high-RFI chickens than in the other 3
groups, suggesting host physiological adaptations to support greater energy and
nutrient needs of high-RFI chickens compensating for the restricted feeding.
IMPORTANCE The impact of the FE-associated differences in feed intake on intestinal
bacterial and host physiological parameters has so far not been clarified. Understanding
the underlying principles is essential for the development of cost-effective
strategies to improve FE in chicken production. Under conditions of quantitative
feed restriction, low- and high-RFI chickens ate the same amount of feed. Therefore,
this research helps in distinguishing intestinal bacterial taxa and functions that were
highly reliant on feed intake from those that were associated with physiological adaptations
to RFI-associated differences in host nutritional needs and intestinal nutrient
availability. This work provides a background for further research to assess manipulation
of the intestinal microbiota, host physiology, and FE in chickens by
dietary intervention.This project (ECO-FCE) has received funding from the European Union’s Seventh
Framework Program for research, technological development, and demonstration under
grant agreement 311794