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Comparison of single radial immunodiffusion and ELISA for the quantification of immunoglobulin G in bovine colostrum, milk and calf sera
Get PDFPublication history: Accepted - 12 October 2017; Published online - 02 November 2017.The overall objective was to compare immunoglobulin G (IgG) concentrations measured by single radial
immunodiffusion (sRID) and ELISA-based methods in samples of bovine colostrum and transition milk
from contrasting breed types (Limousin × Friesian (n = 10) and Holstein (n = 10)). Jugular blood samples
were collected at 48 h post-birth from beef (n = 10) and dairy (n = 10) calves and sera harvested
subsequent to colostrum consumption. Absolute colostrum IgG values determined by ELISA showed
poor agreement with mean (SD) IgG values measured using sRID, fixed bias (sRID – ELISA) was 31.89
(±9.84) mg/mL; having wide limits of agreement (12.61–51.17) and a low concordance coefficient
(0.26). The agreement between ELISA and sRID when measuring serum IgG was greater than that of
colostrum, fixed bias (sRID – ELISA) was 12.36 (±6.60) mg/mL; having narrower limits of agreement
(−0.58 to 25.30) and serum IgG concentrations had a greater concordance coefficient (0.44) between
samples. Calf sera IgG measured using the indirect zinc sulphate turbidity test showed a strong
correlation with the sRID and ELISA methods (P < .001), R2 = 0.78 and R2 = 0.77 respectively. Overall, the
ELISA and sRID methodologies had a strong positive association with almost a twofold (1.8) difference
between values; therefore, they provide diverse absolute values of IgG concentration
Plant and soil nutrient stoichiometry along primary ecological successions: Is there any link?
Get PDFPublication history: Accepted - 20 July 2017; Published - 7 August 2017.Ecological stoichiometry suggests that plant Nitrogen (N)-to-Phosphorus (P) ratios respond
to changes in both soil N:P stoichiometry and soil N and P availability. Thus we would expect
that soil and plant N:P ratios be significantly related along natural gradients of soil development
such as those associated with primary ecological successions. Here we explicitly
search for linkages between plant and soil N:P stoichiometry along four primary successions
distributed across Europe. We measured N and P content in soils and plant compartments
(leaf, stem and root) of 72 wild plant species distributed along two sand dune and two glacier
successions where soil age ranges from few to thousand years old. Overall we found that
soil N:P ratios strongly increased along successional stages, however, plant N:P ratios were
neither related to soil N:P stoichiometry nor to changes in soil N and P availability. Instead
changes in plant nutrient stoichiometry were ªdrivenº by plant-functional-group identity. Not
only N:P ratios differed between legumes, grasses and forbs but each of these plant functional
groups maintained N:P ratios relatively constant across pioneer, middle and advanced
successional stages. Our evidence is that soil nutrient stoichiometry may not be a good predictor
of changes in plant N:P stoichiometry along natural primary ecological successions,
which have not reached yet a retrogressive stage. This could be because wild-plants rely
on mechanisms of internal nutrient regulation, which make them less dependent to changes
in soil nutrient availability under unpredictable environmental conditions. Further studies
need to clarify what underlying evolutionary and eco-physiological mechanisms determine
changes in nutrient stoichiometry in plant species distributed across natural environmental
gradients.This research was funded by a Vice-
Chancellor Scholarship from University of Ulster,
UK
Bovine tuberculosis visible lesions in cattle culled during herd breakdowns: the effects of individual characteristics, trade movement and co-infection
Get PDFPublication history: Accepted - 14 December 2017; Published online - 29 December 2017.Background: Bovine tuberculosis (bTB), caused by Mycobacterium bovis, remains a significant problem for livestock
industries in many countries worldwide including Northern Ireland, where a test and slaughter regime has utilised
the Single Intradermal Comparative Cervical Tuberculin (SICCT) test since 1959.
We investigated the variation in post-mortem confirmation based on bTB visible lesion (VL) presence during herd
breakdowns using two model suites. We investigated animal-level characteristics, while controlling for herd-level
factors and clustering. We were interested in potential impacts of concurrent infection, and therefore we assessed
whether animals with evidence of liver fluke infection (Fasciola hepatica; post-mortem inspection), M. avium reactors
(animals with negative M. bovis-avium (b-a) tuberculin reactions) or Bovine Viral Diarrhoea Virus (BVDV; RT-PCR tested)
were associated with bTB confirmation.
Results: The dataset included 6242 animals removed during the 14 month study period (2013–2015). bTB-VL presence
was significantly increased in animals with greater b-a reaction size at the disclosing SICCT test (e.g. b-a = 5-
9 mm vs. b-a = 0 mm, adjusted Odds ratio (aOR): 14.57; p < 0.001). M. avium reactor animals (b-a < 0) were
also significantly more likely to disclose VL than non-reactor animals (b-a = 0; aOR: 2.29; p = 0.023). Animals had a
greater probability of exhibiting lesions with the increasing number of herds it had resided within (movement; logherds: aOR: 2.27–2.42; p < 0.001), if it had an inconclusive penultimate test result (aOR: 2.84–3.89; p < 0.001), and with
increasing time between tests (log-time; aOR: 1.23; p = 0.003). Animals were less likely to have VL if they were a dairy
breed (aOR: 0.79; p = 0.015) or in an older age-class (e.g. age-quartile 2 vs. 4; aOR: 0.65; p < 0.001). Liver fluke
or BVDV variables were not retained in either multivariable model as they were non-significantly associated
with bTB-VL status (p > 0.1).
Conclusions: Our results suggest that neither co-infection of liver fluke nor BVDV had a significant effect on
the presence of VLs in this high-risk cohort. M. avium tuberculin reactors had a significantly increased risk of
disclosing with a bTB lesion, which could be related to the impact of co-infection with M. avium subsp. paratuberculosis
(MAP) affecting the performance of the SICCT however further research in this area is required. Movements, test history,
breed and age were important factors influencing confirmation in high-risk animals.This work was funded as part of a broader study of concurrent infections and their role in bTB epidemiology in Northern Ireland (48005 (122035): 15/3/10 − bTB Endemic Diseases; PI: Dr. Andrew Byrne) funded under the Evidence and Innovation (E&I) Scheme by the Department of Agriculture and Rural Development (DAERA; www.daera-ni.gov.uk)
Finishing pigs that are divergent in feed efficiency show small differences in intestinal functionality and structure
No full textPublication history: Accepted - 17 March 2017; Published online - 5 April 2017.Controversial information is available regarding the feed efficiency-related variation in intestinal size, structure and functionality in pigs. The present objective was therefore to investigate the differences in visceral organ size, intestinal morphology, mucosal enzyme activity,
intestinal integrity and related gene expression in low and high RFI pigs which were reared
at three different geographical locations (Austria, AT; Northern Ireland, NI; Republic of Ireland, ROI) using similar protocols. Pigs (n = 369) were ranked for their RFI between days 42
and 91 postweaning and low and high RFI pigs (n = 16 from AT, n = 24 from NI, and n = 60
from ROI) were selected. Pigs were sacrificed and sampled on ~day 110 of life. In general,
RFI-related variation in intestinal size, structure and function was small. Some energy saving mechanisms and enhanced digestive and absorptive capacity were indicated in low
versus high RFI pigs by shorter crypts, higher duodenal lactase and maltase activity and
greater mucosal permeability (P < 0.05), but differences were mainly seen in pigs from AT
and to a lesser degree in pigs from ROI. Additionally, low RFI pigs from AT had more goblet
cells in duodenum but fewer in jejunum compared to high RFI pigs (P < 0.05). Together with
the lower expression of TLR4 and TNFA in low versus high RFI pigs from AT and ROI (P <
0.05), these results might indicate differences in the innate immune response between low
and high RFI pigs. Results demonstrated that the variation in the size of visceral organs and
intestinal structure and functionality was greater between geographic location (local environmental factors) than between RFI ranks of pigs. In conclusion, present results support previous findings that the intestinal size, structure and functionality do not significantly contribute
to variation in RFI of pigs.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
Market impact of Foot-and-Mouth Disease control strategies: a UK case study
Get PDFPublication history: Accepted - 26 July 2017; Published - 01 September 2017.Foot-and-mouth disease (FMD) poses a serious threat to the agricultural sector due
to its highly contagious nature. Outbreaks of FMD can lead to substantial disruptions
to livestock markets due to loss of production and access to international markets.
In a previously FMD-free country, the use of vaccination to augment control of an FMD
outbreak is increasingly being recognized as an alternative control strategy to direct
slaughtering [stamping-out (SO)]. The choice of control strategy has implications on production,
trade, and hence prices of the sector. Specific choice of eradication strategies
depends on their costs and benefits. Economic impact assessments are often based
on benefit–cost framework, which provide detailed information on the changes in profit
for a farm or budget implications for a government (1). However, this framework cannot
capture price effects caused by changes in production due to culling of animals; access
to international markets; and consumers’ reaction. These three impacts combine to
affect equilibrium within commodity markets (2). This paper provides assessment of sectoral
level impacts of the eradication choices of FMD outbreaks, which are typically not
available from benefit–cost framework, in the context of the UK. The FAPRI-UK model,
a partial equilibrium model of the agricultural sector, is utilized to investigate market
outcomes of different control strategies (namely SO and vaccinate-to-die) in the case of
FMD outbreaks. The outputs from the simulations of the EXODIS epidemiological model
(number of animals culled/vaccinated and duration of outbreak) are used as inputs within
the economic model to capture the overall price impact of the animal destruction, export
ban, and consumers’ response
The Promise, Practice, and State of Planning Tools to Assess Site Vulnerability to Runoff Phosphorus Loss
Get PDFPublication history: Accepted - 23 October 2017; Published online - 1 November 2017.Over the past 20 yr, there has been a proliferation of phosphorus
(P) site assessment tools for nutrient management planning,
particularly in the United States. The 19 papers that make up this
special section on P site assessment include decision support
tools ranging from the P Index to fate-and-transport models to
weather-forecast-based risk calculators. All require objective
evaluation to ensure that they are effective in achieving intended
benefits to protecting water quality. In the United States, efforts
have been underway to compare, evaluate, and advance an
array of P site assessment tools. Efforts to corroborate their
performance using water quality monitoring data confirms
previously documented discrepancies between different P
site assessment tools but also highlights a surprisingly strong
performance of many versions of the P Index as a predictor of
water quality. At the same time, fate-and-transport models, often
considered to be superior in their prediction of hydrology and
water quality due to their complexity, reveal limitations when
applied to site assessment. Indeed, one consistent theme from
recent experience is the need to calibrate highly parameterized
models. As P site assessment evolves, so too do routines
representing important aspects of P cycling and transport. New
classes of P site assessment tools are an opportunity to move P
site assessment from general, strategic goals to web-based tools
supporting daily, operational decision
Measles vaccination: Threat from related veterinary viruses and need for continued vaccination post measles eradication
Get PDFPublication history: Accepted - 3 November2017; Published online - 14 December 2017Measles virus (MV) is the only human virus within the morbillivirus genus of the Paramyxoviridae. The veterinary members are canine distemper virus (CDV), peste des petits ruminants virus (PPRV), Rinderpest Virus (RPV) as well as the marine morbilliviruses phocine distemper virus (PDV), dolphin morbillivirus (DMV) and porpoise morbillivirus (PMV). Morbilliviruses have a severe impact on humans and animal species. They confer diseases which have contributed to morbidity and mortality of the population on a global scale. There is substantial evidence from both natural and experimental infections that morbilliviruses can readily cross species barriers. Of most concern with regard to zoonosis is the more recently reported fatal infection of primates in Japan and China with strains of CDV which have adapted to this host. The close genetic relationship, shared cell entry receptors and similar pathogenesis between the morbilliviruses highlights the potential consequences of complete withdrawal of MV vaccination after eradication. Therefore, it would be prudent to continue the current MV vaccination. Ultimately development of novel, safe vaccines which have higher efficacy against the veterinary morbilliviruses is a priority. These would to protect the human population long term against the threat of zoonosis by these veterinary viruses
The In Vitro and In Vivo Effect of Carvacrol in Preventing Campylobacter Infection, Colonization and in Improving Productivity of Chicken Broilers
No full textPublication history: Accepted - 27 February 2017; Published online - 1 June 2017.The current trend in reducing the antibiotic usage in animal production imposes urgency in the identification of novel biocides. The essential oil carvacrol, for example, changes the morphology of the cell and acts against a variety of targets within the bacterial membranes and cytoplasm, and our in vitro results show that it reduces adhesion and invasion of chicken intestinal primary cells and also biofilm formation. A trial was conducted to evaluate the effects of dietary supplementation of carvacrol at four concentrations (0, 120, 200, and 300 mg/kg of diet) on the performance of Lactobacillus spp., Escherichia coli, Campylobacter spp., and broilers. Each of the four diets was fed to three replicates/trial of 50 chicks each from day 0 to 35. Our results show that carvacrol linearly decreased feed intake, feed conversion rates and increased body weight at all levels of supplementation. Plate count analysis showed that Campylobacter spp. was only detected at 35 days in the treatment groups compared with the control group where the colonization occurred at 21 days. The absence of Campylobacter spp. at 21 days in the treatment groups was associated with a significant increase in the relative abundance of Lactobacillus spp. Also, carvacrol was demonstrated to have a significant effect on E. coli numbers in the cecum of the treatment groups, at all supplementation levels. In conclusion, this study shows for the first time that at different concentrations, carvacrol can delay Campylobacter spp., colonization of chicken broilers, by inducing changes in gut microflora, and it demonstrates promise as an alternative to the use of antibiotics
The in vitro and ex vivo effect of Auranta 3001 in preventing Cryptosporidium hominis and Cryptosporidium parvum infection
Get PDFPublication history: Accepted - 27 July 2017; Published online - 31 August 2017.Background: Cryptosporidium is a major cause of diarrhea worldwide in both humans and farm animals with no
completely effective treatment available at present. In this study, we assessed the inhibitory effect of different concentrations
of Auranta 3001 (0.1, 0.5 and 1%), a novel natural feed supplement, on C. hominis and C. parvum invasion of
human ileocecal adenocarcinoma (HCT-8), bovine primary cells and C. parvum invasion of HCT-8, bovine primary cells
and bovine intestinal biopsies. The effect of the feed supplement on the production of pro-inflammatory cytokines
IL-8 and INF-γ, the anti-inflammatory cytokine IL-10, the expression of CpSUB1 protease gene during infection was
also assessed by quantitative PCR (q-PCR). Transepithelial electrical resistance (TEER) was employed to measure the
integrity of tight junction dynamics of the culture models.
Results: Pre-treatment of intestinal cells or oocysts with the Auranta 3001 significantly reduced the invasiveness of C.
hominis and C. parvum against HCT-8 and bovine primary cells in a dose dependent manner. The most pronounced
reduction in the invasiveness of both parasites was observed when Auranta 3001 was present during infection. Levels
of IL-8 were significantly reduced in both HCT-8 and bovine primary cells, while the levels of INF-γ and IL-10 showed
opposite trends in the two cell lines during infection in the presence of Auranta 3001. CpSUB1 gene protease expression,
which mediates infection, was significantly reduced suggesting that this enzyme is a possible target of Auranta
3001.
Conclusions: Although, C. hominis and C. parvum use different invasion mechanisms to infect cells, the novel feed
additive can significantly attenuate the entry of Cryptosporidium in HCT-8 cells, primary bovine cells and bovine intestinal
biopsies and thus provide an alternative method to control cryptosporidiosis.This work has been funded through a research grant awarded to NC by
Auranta, Nova UCD, Belfield Innovation Park, Belfield, Dublin 4, Ireland
Effect of different levels of protein concentrates supplementation on the growth performance, plasma amino acids profile and mTOR cascade genes expression in early-weaned yak calves
Get PDFPublication history: Accepted - 13 June 2017; Published online - 27 June 2017Objective
This study evaluated the effects of different levels of protein concentrate supplementation on the growth performance of yak calves, and correlated the growth rate to changes occurring in the plasma- amino acids, -insulin profile, and signaling activity of mammalian target of rapamycin (mTOR) cascade to characterize the mechanism through which the protein synthesis can be improved in early weaned yaks.
Methods
For this study, 48 early (3 months old) weaned yak calves were selected, and assigned into four dietary treatments according to randomized complete block design. The four blocks were balanced for body weight and sex. The yaks were either grazed on natural pasture (control diet) in a single herd or the grazing yaks was supplemented with one of the three protein rich supplements containing low (17%; LP), medium (19%; MP), or high (21%; HP) levels of crude proteins for a period of 30 days.
Results
Results showed that the average daily gain of calves increased (0.14 vs 0.23–0.26 kg; p0.05) when the grazing calves were supplemented with protein concentrates. Compared to control diet, the insulin level of calves increased (p<0.05; 1.86 vs 2.16–2.54 μIU/mL) with supplementation of protein concentrates. Addition of protein concentrates up-regulated (p<0.05) expression of mTOR-raptor, mammalian vacuolar protein sorting 34 homolog, the translational regulators eukaryotic translation initiation factor 4E binding protein 1, and S6 kinase 1 genes in both Longissimus dorsi and semitendinosus. In contrast, the expression of sequestosome 1 was down-regulated in the concentrate supplemented calves.
Conclusion
Our results show that protein supplementation improves the growth performance of early weaned yak calves, and that plasma methionine and insulin concentrations were the key mediator for gene expression and protein deposition in the muscles.This research project was supported by grants from the Cattle System Special Research Funds (CARS-38)