3709 research outputs found
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Implementation of compact calving at the farm level: A qualitative analysis of farmers operating pasture-based dairy systems in Ireland
peer-reviewedPasture-based dairy systems aim to maximize the proportion of grazed pasture in the cow's diet by having a compact calving season that coincides with the onset of the grass growing season. In Ireland, where pasture-based systems are dominant, a key performance indicator that reflects the degree of compact calving is referred to as 6-wk calving rate (6-wk CR). Although the industry target is 90%, the national average 6-wk CR in Ireland is currently 67%. The aim of this study was to use qualitative research to understand in depth farmers' experiences in implementing a high 6-wk CR. Ten case-study dairy farmers were interviewed using the biographical narrative interpretive method. We identified 5 broad and often interrelated themes evoked by farmers regarding 6-wk CR: the “good” farmer; support networks; free time and family time; simplicity of a structured system; and profitability and monetary gain. The findings of this study identify complexities and challenges at farm level when it comes to increasing 6-wk CR, such as increased workload and challenges associated with large numbers of male calves born during a condensed calving season. Benefits experienced by farmers as a result of increasing 6-wk CR included increased days in milk and consequently improved cash flow as well as increased grass utilization. Our findings are of interest to researchers and extension agents involved in programs concerned with reproductive management in pasture-based dairy systems
Antimicrobial activity, molecular typing and in vitro safety assessment of Lactococcus garvieae isolates from healthy cultured rainbow trout (Oncorhynchus mykiss, Walbaum) and rearing environment
peer-reviewedLactococcus garvieae is the aetiological agent of lactococcosis, an ichthyopathology affecting rainbow trout (Oncorhynchus mykiss, Walbaum) farming and having recently been considered as a potential food-borne zoonotic agent. This work aims to characterise a population of 53 L. garvieae isolates from healthy cultured rainbow trout and rearing environment by using microbiological, biochemical and genetic assays to unveil the potential impact that their presence may have, not only for fish, but also for consumers. The lactococci exhibited a broad antimicrobial spectrum against Gram-negative ichthyopathogens, likely due to production of organic acids. The 53 L. garvieae isolates were grouped into two and five genetic clusters by PFGE and ERIC-PCR, respectively. All the lactococcal isolates produce α-haemolysis and harbour, at least, 10 putative virulence factors (hly-1, hly-2, hly-3, NADH oxidase, sod, pgm, adhPsaA, eno, LPxTG-3 and adhCI). While all the lactococci were resistant to streptomycin and clindamycin, no resistance genes were found. The manuscript concludes that the non-existence of active lactococcosis does not guarantee the absence of potentially virulent L. garvieae, which also exhibit a great capacity for adaptation and persistence in the environment. Furthermore, the antibiotic resistance profile shown may lead to re-evaluate the treatments of choice in human patients
Effect of a bacteriocin-producing Streptococcus salivarius on the pathogen Fusobacterium nucleatum in a model of the human distal colon
peer-reviewedThe gut microbiome is a vast reservoir of microbes, some of which produce antimicrobial peptides called bacteriocins that may inhibit specific bacteria associated with disease. Fusobacterium nucleatum is an emerging human bacterial pathogen associated with gastrointestinal diseases including colorectal cancer (CRC). In this study, fecal samples of healthy donors were screened for potential bacteriocin-producing probiotics with antimicrobial activity against F. nucleatum. A novel isolate, designated as Streptococcus salivarius DPC6993 demonstrated a narrow-spectrum of antimicrobial activity against F. nucleatum in vitro. In silico analysis of the S. salivarius DPC6993 genome revealed the presence of genes involved in the production of the bacteriocins salivaricin A5 and salivaricin B. After 6 h in a colon fermentation model, there was a significant drop in the number of F. nucleatum in samples that had been simultaneously inoculated with S. salivarius DPC6993 + F. nucleatum DSM15643 compared to those inoculated with F. nucleatum DSM15643 alone (mean ± SD: 9243.3 ± 3408.4 vs 29688.9 ± 4993.9 copies/μl). Furthermore, 16S rRNA amplicon analysis revealed a significant difference in the mean relative abundances of Fusobacterium between samples inoculated with both S. salivarius DPC6993 and F. nucleatum DSM15643 (0.05%) and F. nucleatum DSM15643 only (0.32%). Diversity analysis indicated minimal impact exerted by S. salivarius DPC6993 on the surrounding microbiota. Overall, this study highlights the ability of a natural gut bacterium to target a bacterial pathogen associated with CRC. The specific targeting of CRC-associated pathogens by biotherapeutics may ultimately reduce the risk of CRC development and positively impact CRC outcomes.RÍSA
Validation of maternal and terminal sheep breeding objectives using Irish field data
peer-reviewedGenetic evaluations provide producers with a tool to aid in breeding decisions and highlight the increase in performance achievable at the farm level through genetic gain. Despite this, large-scale validation of sheep breeding objectives using field data is lacking in the scientific literature. The objective of the present study was to evaluate the phenotypic differences for a range of economically important traits for animals divergent in genetic merit for the Irish national maternal and terminal sheep breeding objectives. A dataset of 17,356 crossbred ewes and 54,322 progeny differing in their maternal and terminal breeding index recorded in 139 commercial flocks was available. The association of the maternal index of the ewe or terminal index of the ram and a range of phenotypic performance traits, including lambing, lamb performance, ewe performance, and health traits, were undertaken. Ewes excelling on the maternal index had higher litter sizes and produced progeny with greater perinatal lamb survival, heavier live weights from birth to postweaning and reduced days to slaughter (P 0.05). Results from this study highlight that selecting either ewes or rams of superior maternal or terminal attributes will result in an improvement on pertinent performance traits of the national sheep flock, resulting in greater flock productivity and profitability.Irish Department of Agricultur
Ammonia emissions from agriculture and their contribution to fine particulate matter: A review of implications for human health
peer-reviewedAtmospheric ammonia (NH3) released from agriculture is contributing significantly to acidification and atmospheric NH3 may have on human health is much less readily available. The potential direct impact of NH3 on the health of the general public is under-represented in scientific literature, though there have been several studies which indicate that NH3 has a direct effect on the respiratory health of those who handle livestock. These health impacts can include a reduced lung function, irritation to the throat and eyes, and increased coughing and phlegm expulsion. More recent studies have indicated that agricultural NH3 may directly influence the early on-set of asthma in young children. In addition to the potential direct impact of ammonia, it is also a substantial contributor to the fine particulate matter (PM2.5) fraction (namely the US and Europe); where it accounts for the formation of 30% and 50% of all PM2.5 respectively. PM2.5 has the ability to penetrate deep into the lungs and cause long term illnesses such as Chronic Obstructive Pulmonary Disease (COPD) and lung cancer. Hence, PM2.5 causes economic losses which equate to billions of dollars (US) to the global economy annually. Both premature deaths associated with the health impacts from PM2.5 and economic losses could be mitigated with a reduction in NH3 emissions resulting from agriculture. As agriculture contributes to more than 81% of all global NH3 emissions, it is imperative that food production does not come at a cost to the world's ability to breathe; where reductions in NH3 emissions can be easier to achieve than other associated pollutants
Irish Grassland Research — main achievements and advancements in the past 60 yrs and where to progress to next
peer-reviewedIn the last 60 yr Irish grassland production has increased substantially in no small part due to high-quality fundamental grassland research. Increased production from grassland has arisen from improved understanding (research and practice) of soil and plant nutrition, plant physiology and variety improvement, while improved understanding of feed evaluation, ruminant nutrition, grazing management and silage technology has contributed to increased utilisation of grassland. Annual grass DM production varies from 12.7 to 15.0 t DM/ha based on Department of Agriculture, Food and the Marine grass variety trials. More recent data from PastureBase Ireland indicate that average annual grass production (2020) on efficient dairy and dry stock farms is 13.5 and 10.0 t DM/ha, respectively. Ireland is now one of the world leaders in grassland research, particularly in the area of grazing utilisation, the development and use of grassland databases, decision support systems and grass selection indices for grass varieties. Future pasture-based systems must extend beyond food production to deliver additional benefits to farmers, to consumers and the wider society. Future systems will require more robust grazing animals with healthier functional traits, more diverse swards supporting improved animal performance and require fewer fertiliser and chemical inputs, and will support more biodiversity and enhanced carbon storage
Irish dairy and drystock farmers’ attitudes and perceptions to planting trees and adopting agroforestry practices on their land
peer-reviewedDue to the intensification of agriculture and transition to monoculture plantations, vast areas of native woodland have been lost from the Irish landscape. As these trees gradually vanished from agricultural land, the use of traditional, ancient agroforestry practices dwindled. Currently, forestry cover in Ireland is 25% lower than the European average, with the rate of afforestation remaining critically low. Agroforestry has been cited as a means to increase forestry cover in Ireland while continuing to produce viable high quality agricultural products on the same parcel of land. However, even with a range of afforestation schemes available, farmers exhibit an evident reluctance to adopt agroforestry. This research aimed to examine the main attitudes and perceptions of Irish dairy and drystock farmers to planting trees on their land and adopting agroforestry practices. The majority of farmers included within the dataset exhibited a positive attitude towards trees on their farms, with the main negative behavioural beliefs relating to impacts on pasture. Family and Teagasc (The Irish Agriculture and Food Development Authority) are the highest cited influential bodies while the majority of farmers exhibit high perceived behavioural control. Intention rates to plant trees are high, albeit mainly on marginal areas of the farm. Agroforestry knowledge is low in Ireland with the word itself eliciting negative responses amongst the farming community. The results provide a comprehensive understanding of the main attitudes, influential bodies and barriers that affect agroforestry uptake in Ireland.Teagas
Enteric methane research and mitigation strategies for pastoral-based beef cattle production systems
peer-reviewedRuminant livestock play a key role in global society through the conversion of lignocellulolytic plant matter into high-quality sources of protein for human consumption. However, as a consequence of the digestive physiology of ruminant species, methane (CH4), which originates as a byproduct of enteric fermentation, is accountable for 40% of global agriculture's carbon footprint and ~6% of global greenhouse gas (GHG) emissions. Therefore, meeting the increasing demand for animal protein associated with a growing global population while reducing the GHG intensity of ruminant production will be a challenge for both the livestock industry and the research community. In recent decades, numerous strategies have been identified as having the potential to reduce the methanogenic output of livestock. Dietary supplementation with antimethanogenic compounds, targeting members of the rumen methanogen community and/or suppressing the availability of methanogenesis substrates (mainly H2 and CO2), may have the potential to reduce the methanogenic output of housed livestock. However, reducing the environmental impact of pasture-based beef cattle may be a challenge, but it can be achieved by enhancing the nutritional quality of grazed forage in an effort to improve animal growth rates and ultimately reduce lifetime emissions. In addition, the genetic selection of low-CH4-emitting and/or faster-growing animals will likely benefit all beef cattle production systems by reducing the methanogenic potential of future generations of livestock. Similarly, the development of other mitigation technologies requiring minimal intervention and labor for their application, such as anti-methanogen vaccines, would likely appeal to livestock producers, with high uptake among farmers if proven effective. Therefore, the objective of this review is to give a detailed overview of the CH4 mitigation solutions, both currently available and under development, for temperate pasture-based beef cattle production systems. A description of ruminal methanogenesis and the technologies used to estimate enteric emissions at pastures are also presented.Funding and support from the FACCE ERA-GAS RumenPredict grant (16/RD/ERAGAS/1RUMENPREDICTROI 2017) and Horizon 2020 MASTER grant (818368) is acknowledged. PS was funded by a Teagasc Walsh Scholarship (RMIS 0364)
Short rotation forestry – The interface between agricultural production and conventional forestry
peer-reviewedShort rotation forestry (SRF) is a form of forest management designed to maximise woody biomass production on single stems over rotation lengths much shorter than the 40+ years of conventional forestry. The objective of the Irish “Forestry for Fibre” scheme is to address a forecasted shortfall in the supply of fibre for the energy and wood products sectors by incentivising the establishment of Italian alder, hybrid aspen, poplar, and eucalyptus plantations. To date there has been little take-up. ShortFor (2013 to 2018) was a recent research project funded by DAFM to examine the potential for SRF in Ireland. In addition to reviewing candidate species the project evaluated likely establishment practice and silviculture specifically suited to SRF. The project also set up field trials to assess the impact of stocking density on growth and yield. Further work also assessed the quality and calorific value of biomass produced by key species and the sustainability of suitable management / production systems
The effect of natural and induced calving of beef heifers on stress-related gene expression and maternal health and immunity
peer-reviewedThe peri-partum processes can exert stress on a cow on many levels. There is little evidence about acute stress around the calving event and subsequent potential effects for the cows’ immunological status or subsequent reproductive health. To investigate this, 55 crossbred recipient beef heifers carrying purebred Simmental embryos were assigned to one of three groups on day 285 of gestation: (i) control (no parturition induction treatment; n = 19); (ii) induction of parturition with corticosteroid (n = 20) and (iii) induction of parturition with corticosteroid plus prostaglandin (n = 16). Interval from induction of parturition to calving and calving ease was recorded. Reproductive tract examinations were conducted on Day 21 (D21) and Day 42, and a sample was obtained for the determination of uterine cytology on D21. Blood samples were taken from the dams two weeks before parturition, one day after parturition (D1) and two weeks after parturition (D14) for gene expression and cortisol and calcium concentration determination. Calves were weighed at birth and subsequently every week until they were 10 weeks of age. A colostrum sample was taken immediately after calving and stored for subsequent Immunoglobin G (IgG) concentration analysis. Data were analysed using ANOVA with posthoc Tukey, Spearman correlation and stepwise backwards linear regression using SAS. Quantitative reverse transcription PCR was performed on the following immune genes: Interleukins IL1a and b, IL2, IL4, IL8, Tumour Necrosis Factor Alpha, Interferon-gamma, Lymphotoxin, Toll-Like Receptor, Nuclear factor of kappa light polypeptide gene enhancer in B cells 1 and 2, glucocorticoid receptor alpha, as well as the neutrophil genes that regulate inflammation: Fas, L-selectin, MMP-9 and BPI. The results show that compared with non-induced contemporaries, induction has no negative effect on dystocia or subsequent calf weight gain but can have a positive effect on colostral IgG concentration. Blood calcium concentrations on both D1 and D14 postcalving are associated with subsequent uterine health. Parturition events were reflected in temporal changes in the expression of the cytokines IFNγ, TNFα, IL1b, IL4, IL8 and Haptoglobin in the dams’ blood, all of which are associated with the immune competence of the cow during this period. The conclusion is that induction of calving can have a positive effect on colostral IgG concentration. Calcium concentrations postcalving are associated with subsequent reproductive tract health. Events associated with the peri- and postpartum period are all reflected in temporal changes in immune function-related cytokines