• C:N:P stoichiometry and nutrient limitation of the soil microbial biomass in a grazed grassland site under experimental P limitation or excess

      Griffiths, Bryan S; Spilles, Annette; Bonkowski, Michael (Biomed Central, 2012-06-21)
      Introduction: The availability of essential nutrients, such as nitrogen (N) and phosphorus (P), can feedback on soil carbon (C) and the soil microbial biomass. Natural cycles can be supplemented by agricultural fertiliser addition, and we determined whether the stoichiometry and nutrient limitation of the microbial biomass could be affected by an unbalanced nutrient supply. Methods: Samples were taken from a long-term trial (in effect since 1968) with annual applications of 0, 15 and 30 kg P ha−1 with constant N and potassium. Soil and microbial biomass CNP contents were measured and nutrient limitation assessed by substrate-induced respiration. Linear regression and discriminant analyses were used to identify the variables explaining nutrient limitation. Results: Soil and biomass CNP increased with increasing P fertiliser, and there was a significant, positive, correlation between microbial biomass P and biomass C, apart from at the highest level of P fertilisation when the microbial biomass was over-saturated with P. The molar ratios of C:N:P in the microbial biomass remained constant (homeostatic) despite large changes in the soil nutrient ratios. Microbial growth was generally limited by C and N, except in soil with no added P when C and P were the main limiting nutrients. C, N and P, however, did not explain all the growth limitation on the soils with no added P. Conclusions: Increased soil C and N were probably due to increased net primary production. Our results confirm that C:N:P ratios within the microbial biomass were constrained (i.e. homeostatic) under near optimum soil conditions. Soils with no added P were characterised by strong microbial P limitation and soils under high P by over-saturation of microorganisms with P. Relative changes in biomass C:P can be indicative of nutrient limitation within a site.
    • Calf Health and Immunity.

      Earley, Bernadette; Fallon, Richard J. (Teagasc, 1999-11-01)
      Suckled calves had significantly higher serum IgG 1 concentrations than mart purchased dairy calves. The marked differences in immunoglobulin levels between suckled calves and dairy calves suggest that these calves received either insufficient quality or quantity of colostral immunoglobulins. Factors affecting calf serum Ig concentrations are, Ig concentration in colostrum, colostrum intake, Ig mass, calf age at first feeding, nutrition of the dam, method of ingestion, presence of the dam, age of the dam and the calf. When suckled calves were fed a similar volume of colostrum relative to birth weight (40 ml/kg) and at the same time interval post birth, there was no significant difference across the three suckler herd progeny for IgG1, IgA and IgM and total Ig serum levels at 28 and 56 days of age. However, serum IgG2 levels were significantly lower in the Limousin x beef breed when compared with the Charolais x beef breed suckled calves at 28 days of age. Healthy calves had higher serum immunoglobulins (IgG1) than calves treated for respiratory disease, enteric disease or for both respiratory disease and enteric disease. It is well recognised that immunoglobulins are absorbed from the intestine for only a short period post birth and that efficiency of absorption is dependent on ensuring that the calf receives adequate colostrum in the immediate post-partum period. Low serum IgG1 concentrations are attributable to failures to obtain adequate colostral immunoglobulins in the period immediately following birth. The mean IgA and IgM serum levels of suckled calves in the present study were only slightly higher than dairy calves while IgG1 serum levels were almost approximately twice as high. Feeding colostrum high in Ig results in higher calf serum Ig concentrations at 48h. The low serum Ig levels reported in the present study suggest that dairy calves failed to obtain adequate transfer of colostral immunoglobulins. Calves with a lower immune status are more susceptible to neonatal infection and thus the importance of colostrum in the immediate post partum period cannot be overemphasised. Thus, the identification of calves with low levels of immunity might stimulate calf producers to ensure that calves receive adequate levels of colostral immunoglobulins. The implications of the present findings are that compared with suckled calves, dairy calves are not receiving 1). adequate quantity of colostrum 2). adequate quality of colostrum. 3). Colostrum soon enough post birth 4). or a combination of all of the previous factors. Rearing calves outdoors using calf jackets had no beneficial effect on calf performance. The incidence of respiratory disease was higher in calves reared indoor when compared with calves reared outdoor with and without jackets. There was an increased incidence of diarrhoea in calves reared outdoors irrespective of calf jacket. Lymphocytes from calves with respiratory disease manifest an impaired capability to blast in vitro. Chromium (Cr) supplementation (250 mg/kg dry matter intake) enhanced the blastogenic response in healthy calves, while, calves with respiratory had impaired blastogenic responses. Supplementation with organic Cr (250 mg/kg dry matter intake) for 63 days had no major effect on physiological parameters and had select effects on haematological parameters, namely, the % monocytes. The % monocytes were significantly higher in the standard commercial milk replacer (CMR) (Skim) Cr supplemented calves when compared with the whey based (CMR) + Soya Brand B or whey based CMR + Soya Brand C or whey based enzyme processed soya Brand C + Cr treatment groups.
    • Calf health from birth to weaning. I. General aspects of disease prevention

      Lorenz, Ingrid; Mee, John F; Earley, Bernadette; More, Simon J (Biomed Central, 2011-09-16)
      Calfhood diseases have a major impact on the economic viability of cattle operations. This is the first in a three part review series on calf health from birth to weaning, focusing on preventive measures. The review considers both pre- and periparturient management factors influencing calf health, colostrum management in beef and dairy calves and further nutrition and weaning in dairy calves.
    • Calf health from birth to weaning. III. Housing and management of calf pneumonia

      Lorenz, Ingrid; Earley, Bernadette; Gilmore, John; Hogan, Ian; Kennedy, Emer; More, Simon J (Biomed Central, 2011-10-21)
      Calfhood diseases have a major impact on the economic viability of cattle operations. A three part review series has been developed focusing on calf health from birth to weaning. In this paper, the last of the three part series, we review disease prevention and management with particular reference to pneumonia, focusing primarily on the pre-weaned calf. Pneumonia in recently weaned suckler calves is also considered, where the key risk factors are related to the time of weaning. Weaning of the suckler calf is often combined with additional stressors including a change in nutrition, environmental change, transport and painful husbandry procedures (castration, dehorning). The reduction of the cumulative effects of these multiple stressors around the time of weaning together with vaccination programmes (preconditioning) can reduce subsequent morbidity and mortality in the feedlot. In most studies, calves housed individually and calves housed outdoors with shelter, are associated with decreased risk of disease. Even though it poses greater management challenges, successful group housing of calves is possible. Special emphasis should be given to equal age groups and to keeping groups stable once they are formed. The management of pneumonia in calves is reliant on a sound understanding of aetiology, relevant risk factors, and of effective approaches to diagnosis and treatment. Early signs of pneumonia include increased respiratory rate and fever, followed by depression. The single most important factor determining the success of therapy in calves with pneumonia is early onset of treatment, and subsequent adequate duration of treatment. The efficacy and economical viability of vaccination against respiratory disease in calves remains unclear.
    • Can the agronomic performance of urea equal calcium ammonium nitrate across nitrogen rates in temperate grassland?

      Forrestal, Patrick J.; Harty, M.A.; Carolan, R.; Watson, C.J.; Lanigan, Gary; Wall, D.P.; Hennessy, Deirdre; Richards, Karl G. (Wiley, 2017-03-23)
      In temperate grassland, urea has been shown to have lower nitrous oxide emissions compared to ammonium nitrate-based fertilizer and is less expensive. However, nitrogen (N) loss via ammonia volatilization from urea raises questions regarding yield performance and efficiency. This study compares the yield and N offtake of grass fertilized with urea, calcium ammonium nitrate (CAN) and urea treated with the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) at six site-years. Five annual fertilizer N rates (100–500 kg N/ha) were applied in five equal splits of 20–100 kg N/ha during the growing season. On average, urea produced slightly better yields than CAN in spring (103.5% of CAN yield) and slightly poorer yields in summer (98.4% of CAN yield). There was no significant difference in annual grass yield between urea, CAN and urea + NBPT. Urea had the lowest cost per tonne of DM grass yield produced. However, the urea treatment had lower N offtake than CAN and this difference was more pronounced as the N rate increased. There was no difference in N offtake between urea + NBPT and CAN. While this study shows that urea produced yields comparable to CAN, urea apparent fertilizer N recovery (AFNR) tends to be lower. Urea selection in place of CAN will increase national ammonia emissions which is problematic for countries with targets to reduce ammonia emissions. Promisingly, NBPT allows the agronomic performance of urea to consistently equal CAN across N rates by addressing the ammonia loss limitations of urea.
    • Can’t See the Wood for the Trees: The Returns to Farm Forestry in Ireland

      Breen, James; Clancy, D.; Ryan, Mary; Wallace, Michael (Teagasc, Oak Park, Carlow, Ireland, 2010)
      The period 2007-2009 witnessed considerable variability in the price of outputs such as milk and cereals and this was compounded by a high degree of volatility in the price of inputs such as fertilizer, animal feed and energy. Previously, Irish farms have used the returns to off-farm employment as well as agricultural support payments such as the Single Farm Payment (SFP) and the Rural Environmental Protection Scheme (REPS) to protect their living standards against low and uncertain agricultural market returns. However, the downturn in the Irish economy has led to a reduction in the availability of off-farm employment and also the discontinuation of REPS. This may lead to an increase in afforestation on Irish farms, as forestry offers greater certainty through the provision of an annual premium in addition to the SFP. However, the decision to afforest represents a significant long-term investment decision that should not be entered into without careful economic consideration. The aim of this paper is to use the Discounted Cash Flow (DCF) analysis method to calculate the returns to forestry under alternative opportunity costs associated with conventional agricultural activities being superseded. The returns to forestry are calculated using the Forestry Investment Value Estimator (FIVE). These returns were then incorporated in the DCF model along with the returns to five conventional agricultural enterprises, which would potentially be superseded by forestry. This approach allows for the calculation of the Net Present Value (NPV) of three forestry scenarios.
    • CAP reform post 2013: Examining the equity dimensions of agricultural support.

      Howley, Peter; Donnellan, Trevor; Hanrahan, Kevin (Teagasc, Oak Park, Carlow, Ireland, 2009)
      Using a dynamic multi-product partial equilibrium model, this paper firstly examines the potential impact of recent policy changes accruing from the mid term review of the Common Agricultural Policy (CAP) in 2003 on the cattle and sheep sectors in Ireland. Secondly, this paper evaluates the potential impact of the implementation of a CAP budget neutral, common EU flat area payment across all Member States. The European Commission has signalled that it will be evaluating current differences in the level of support between Member States as, for example, in the explanatory memorandum accompanying the Commission’s Health Check proposals the Commission argues that it is “increasingly harder to justify the legitimacy of significant individual differences in the support level which are only based on past support” (CEC, 2008; p.18). This paper demonstrates how there are significant differences in the level of CAP payments per hectare across Member States, as generally farmers in more prosperous Western and Nordic countries receive a much higher level of payment per hectare than farmers in relatively poorer Central and Eastern European countries. In relation to Ireland, similar to most other EU-15 countries, farmers benefit from the current inequitable distribution of payments and the results indicate that any move towards equalising the level of payments per hectare will have a significant negative impact on agricultural production and net trade.
    • Cap reform: implications for Ireland

      Howley, Peter; Donnellan, Trevor; Hanrahan, Kevin (Teagasc, Oak Park, Carlow, Ireland, 2009)
      Increasingly farmers can be viewed as multifunctional providers of a range of commodity and non-commodity goods that are valued by society. Changes to the Common Agricultural Policy (CAP) such as the shift towards decoupled payments not only have significant effects on agriculture but also rural areas and society more generally. Given that the CAP is likely to be the most significant driving force for change in the Irish countryside, it will be important to assess the impact of policy changes. Using a dynamic, multi-product, partial equilibrium model, this paper firstly examines the potential impact of recent policy changes accruing from the Mid-Term Review of the Common Agricultural Policy (CAP). In addition, this paper highlights additional potential reforms of the CAP and discusses their implications for the Irish agricultural sector.
    • The capacity to expand milk production in Ireland following the removal of milk quotas

      Lapple, Doris; Hennessy, Thia (Teagasc, 2012-12)
      Given the imminent removal of milk quota in 2015, EU dairy farmers will be able to expand production without purchasing milk quota rights for the first time in 30 years. This paper uses Irish National Farm Survey data to simulate the expansion capacity of Irish dairy farms. Specifically, the likelihood of achieving the 50% increase in production target published in the Irish Government’s Food Harvest 2020 Report is explored. Potential milk output is estimated accounting for structural change and the economic viability of production under three price scenarios for 2020. In addition, the number of new entrants that would be required to meet the 50% target is calculated. The results indicate that the 50% output volume growth target set in the Food Harvest report will be difficult to achieve and that future potential milk output depends importantly on the rate of structural change and productivity growth as well as on real milk prices in 2020. A regional analysis reveals that relative to other regions, the south has the greatest expansion capacity. This suggests that quota removal could cause significant regional restructuring of milk production, which is likely to present some challenges to the dairy processing sector.
    • Capturing the economic benefit of Lolium perenne cultivar performance

      McEvoy, M.; O'Donovan, Michael; Shalloo, Laurence (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
      Economic values were calculated for grass traits of economic importance in Irish grass-based ruminant production systems. Traits considered were those that had the greatest potential to influence the profitability of a grazing system. These were: grass dry matter (DM) yield in spring, mid-season and autumn, grass quality (dry matter digestibility; DMD), 1st and 2nd cut silage DM yield and sward persistency. The Moorepark Dairy Systems Model was used to simulate a dairy farm. Economic values were calculated by simulating the effect of a unit change in the trait of interest while holding all other traits constant. The base scenario involved a fixed herd size and land area (40 ha), and an annual DM yield of 13 t/ha. The economic values generated under the base scenario were: € 0.152/kg for DM yield in spring, € 0.030/kg for DM yield in mid-season and € 0.103/kg for DM yield in autumn; € 0.001, € 0.008, € 0.010, € 0.009, € 0.008 and € 0.006 per 1 g/kg change in DMD for the months of April to September, respectively; € 0.03/kg for 1st cut silage DM yield, € 0.02/kg for 2nd cut silage DM yield; and − € 4.961 for a 1 percent reduction in persistency. Alternative scenarios were examined to determine the sensitivity of the economic values to changes in annual DM yield, sward utilisation and a scenario where silage production was the focus of the system. The economic values were used to calculate a total merit index for each of 20 perennial ryegrass cultivars based on production data from a 3 year plot study. The rank correlation between the merit index values for the cultivars under the base scenario and the scenario involving a reduction in herbage utilisation was 1.0, while that with the scenario involving reduced annual DM yield was 0.94. It is concluded that the total merit index can be used to identify cultivars that can generate the greatest economic contribution to a grass-based production system, regardless of system or intensity of grass production.
    • Carbohydrate catabolic flexibility in the mammalian intestinal commensal Lactobacillus ruminis revealed by fermentation studies aligned to genome annotations

      O’Donnell, Michelle M.; Forde, Brian M; Neville, B; Ross, R Paul; O’Toole, Paul W. (Biomed Central, 2011-08-30)
      Background: Lactobacillus ruminis is a poorly characterized member of the Lactobacillus salivarius clade that is part of the intestinal microbiota of pigs, humans and other mammals. Its variable abundance in human and animals may be linked to historical changes over time and geographical differences in dietary intake of complex carbohydrates. Results: In this study, we investigated the ability of nine L. ruminis strains of human and bovine origin to utilize fifty carbohydrates including simple sugars, oligosaccharides, and prebiotic polysaccharides. The growth patterns were compared with metabolic pathways predicted by annotation of a high quality draft genome sequence of ATCC 25644 (human isolate) and the complete genome of ATCC 27782 (bovine isolate). All of the strains tested utilized prebiotics including fructooligosaccharides (FOS), soybean-oligosaccharides (SOS) and 1,3:1,4-β-D-gluco-oligosaccharides to varying degrees. Six strains isolated from humans utilized FOS-enriched inulin, as well as FOS. In contrast, three strains isolated from cows grew poorly in FOS-supplemented medium. In general, carbohydrate utilisation patterns were strain-dependent and also varied depending on the degree of polymerisation or complexity of structure. Six putative operons were identified in the genome of the human isolate ATCC 25644 for the transport and utilisation of the prebiotics FOS, galacto-oligosaccharides (GOS), SOS, and 1,3:1,4-β-D-Gluco-oligosaccharides. One of these comprised a novel FOS utilisation operon with predicted capacity to degrade chicory-derived FOS. However, only three of these operons were identified in the ATCC 27782 genome that might account for the utilisation of only SOS and 1,3:1,4-β-D-Gluco-oligosaccharides. Conclusions: This study has provided definitive genome-based evidence to support the fermentation patterns of nine strains of Lactobacillus ruminis, and has linked it to gene distribution patterns in strains from different sources. Furthermore, the study has identified prebiotic carbohydrates with the potential to promote L. ruminis growth in vivo.
    • Carbon and nitrogen dynamics and greenhouse gas emissions in constructed wetlands treating wastewater: a review

      Department of Agriculture, Food and the Marine; Jahangir, M.M.R.; Richards, Karl G.; Healy, M. G.; Gill, L.; Muller, C.; Johnston, P.; Fenton, Owen (European Geosciences Union, 2016-01-18)
      The removal efficiency of carbon (C) and nitrogen (N) in constructed wetlands (CWs) is very inconsistent and frequently does not reveal whether the removal processes are due to physical attenuation or whether the different species have been transformed to other reactive forms. Previous research on nutrient removal in CWs did not consider the dynamics of pollution swapping (the increase of one pollutant as a result of a measure introduced to reduce a different pollutant) driven by transformational processes within and around the system. This paper aims to address this knowledge gap by reviewing the biogeochemical dynamics and fate of C and N in CWs and their potential impact on the environment, and by presenting novel ways in which these knowledge gaps may be eliminated. Nutrient removal in CWs varies with the type of CW, vegetation, climate, season, geographical region, and management practices. Horizontal flow CWs tend to have good nitrate (NO3−) removal, as they provide good conditions for denitrification, but cannot remove ammonium (NH4+) due to limited ability to nitrify NH4+. Vertical flow CWs have good NH4+ removal, but their denitrification ability is low. Surface flow CWs decrease nitrous oxide (N2O) emissions but increase methane (CH4) emissions; subsurface flow CWs increase N2O and carbon dioxide (CO2) emissions, but decrease CH4 emissions. Mixed species of vegetation perform better than monocultures in increasing C and N removal and decreasing greenhouse gas (GHG) emissions, but empirical evidence is still scarce. Lower hydraulic loadings with higher hydraulic retention times enhance nutrient removal, but more empirical evidence is required to determine an optimum design. A conceptual model highlighting the current state of knowledge is presented and experimental work that should be undertaken to address knowledge gaps across CWs, vegetation and wastewater types, hydraulic loading rates and regimes, and retention times, is suggested. We recommend that further research on process-based C and N removal and on the balancing of end products into reactive and benign forms is critical to the assessment of the environmental performance of CWs.
    • Carbon and nitrogen dynamics: Greenhouse gases in groundwater beneath a constructed wetland treating municipal wastewater

      Jahangir, Mohammad M. R.; Richards, Karl G.; Fenton, Owen; Carroll, Paul; Harrington, Rory; Johnston, Paul (ESAI, 2014-02-26)
      Constructed wetlands (CW) act as nitrogen (N) sinks and reactors facilitating a number of physical, chemical and biological processes. The N removal efficiency of through-flowing water in such systems when used to treat municipal wastewater is variable. Their overall removal efficiencies do not specifically explain which N species have been removed by physical attenuation, and by biological assimilation or transformation to other forms. A wider understanding of how N removal occurs would help elucidate how losses of N and associated gases from CW impact on water and air quality. The objective of this study is to investigate the C and N cycling processes in the porewater of soils immediately adjacent, up-gradient and down- gradient to helophyte —vegetated CW cells.
    • Carbon cycling in temperate grassland under elevated temperature

      Jansen-Willems, Anne B.; Lanigan, Gary; Grunhage, Ludger; Muller, Christoph (Wiley, 2016-11-01)
      An increase in mean soil surface temperature has been observed over the last century, and it is predicted to further increase in the future. The effect of increased temperature on ecosystem carbon fluxes in a permanent temperate grassland was studied in a long-term (6 years) field experiment, using multiple temperature increments induced by IR lamps. Ecosystem respiration (R-eco) and net ecosystem exchange (NEE) were measured and modeled by a modified Lloyd and Taylor model including a soil moisture component for R-eco (average R2 of 0.78) and inclusion of a photosynthetic component based on temperature and radiation for NEE (R2 = 0.65). Modeled NEE values ranged between 2.3 and 5.3 kg CO2 m−2 year−1, depending on treatment. An increase of 2 or 3°C led to increased carbon losses, lowering the carbon storage potential by around 4 tonnes of C ha−1 year−1. The majority of significant NEE differences were found during night-time compared to daytime. This suggests that during daytime the increased respiration could be offset by an increase in photosynthetic uptake. This was also supported by differences in δ13C and δ18O, indicating prolonged increased photosynthetic activity associated with the higher temperature treatments. However, this increase in photosynthesis was insufficient to counteract the 24 h increase in respiration, explaining the higher CO2 emissions due to elevated temperature.
    • A case of bovine raw milk contamination with Listeria monocytogenes

      Hunt, Karen; Drummond, Niall; Murphy, Mary; Butler, Francis; Buckley, Jim; Jordan, Kieran (Biomed Central, 2012-07-06)
      During routine sampling of bulk raw milk on a dairy farm, the pathogenic bacteria Listeria monocytogenes was found to be a contaminant, at numbers < 100 cfu/ml. A strain with an indistinguishable pulsed-field gel electrophoresis pattern was isolated from the bulk milk two months later. Environmental swabs taken at the dairy environment were negative for the presence of L. monocytogenes, indicating a possible case of excretion of the L. monocytogenes directly into the milk. Milk samples were collected from the individual cows and analysed, resulting in the identification of L. monocytogenes excretion (at 280 cfu/ml) from one of the 4 mammary quarters of one dairy cow out of 180. When the infected cow was isolated from the herd, no L. monocytogenes was detected from the remaining herd. The pulsed-field gel electrophoresis pattern of the strain from the individual cow was indistinguishable from that originally isolated from the bulk milk. The infected cow did not show any clinical signs of disease, nor did the appearance of the milk have any physical abnormalities. Antibiotic treatment of the infected mammary quarter was found to be ineffective. This study shows that there can be risks associated with direct contamination of raw milk with L. monocytogenes.
    • Catabolic flexibility of mammalian-associated lactobacilli

      O'Donnell, Michelle M.; O’Toole, Paul W.; Ross, R Paul (Biomed Central, 2013-05-16)
      Metabolic flexibility may be generally defined as “the capacity for the organism to adapt fuel oxidation to fuel availability”. The metabolic diversification strategies used by individual bacteria vary greatly from the use of novel or acquired enzymes to the use of plasmid-localised genes and transporters. In this review, we describe the ability of lactobacilli to utilise a variety of carbon sources from their current or new environments in order to grow and survive. The genus Lactobacillus now includes more than 150 species, many with adaptive capabilities, broad metabolic capacity and species/strain variance. They are therefore, an informative example of a cell factory capable of adapting to new niches with differing nutritional landscapes. Indeed, lactobacilli naturally colonise and grow in a wide variety of environmental niches which include the roots and foliage of plants, silage, various fermented foods and beverages, the human vagina and the mammalian gastrointestinal tract (GIT; including the mouth, stomach, small intestine and large intestine). Here we primarily describe the metabolic flexibility of some lactobacilli isolated from the mammalian gastrointestinal tract, and we also describe some of the food-associated species with a proven ability to adapt to the GIT. As examples this review concentrates on the following species - Lb. plantarum, Lb. acidophilus, Lb. ruminis, Lb. salivarius, Lb. reuteri and Lb. sakei, to highlight the diversity and inter-relationships between the catabolic nature of species within the genus.
    • A catalogue of validated single nucleotide polymorphisms in bovine orthologs of mammalian imprinted genes and associations with beef production traits

      Magee, D. A.; Berkowicz, Erik W; Sikora, K. M.; Berry, Donagh P.; Park, S. D. E.; Kelly, A. K.; Sweeney, T.; Kenny, David A.; Evans, R. D.; Wickham, B. W.; Spillane, C.; MacHugh, D. E. (Cambridge University Press, 2010-06)
      Genetic (or ‘genomic’) imprinting, a feature of approximately 100 mammalian genes, results in monoallelic expression from one of the two parentally inherited chromosomes. To date, most studies have been directed on imprinted genes in murine or human models; however, there is burgeoning interest in the effects of imprinted genes in domestic livestock species. In particular, attention has focused on imprinted genes that influence foetal growth and development and that are associated with several economically important production traits in cattle, sheep and pigs. We have re-sequenced regions in 20 candidate bovine imprinted genes in order to validate single nucleotide polymorphisms (SNPs) that may influence important production traits in cattle. Putative SNPs detected via re-sequencing were subsequently re-formatted for high-throughput SNP genotyping in 185 cattle samples comprising 138 performance-tested European Bos taurus (all Limousin bulls), 29 African B. taurus and 18 Indian B. indicus samples. Analysis of the resulting genotypic data identified 117 validated SNPs. Preliminary genotype–phenotype association analyses using 83 SNPs that were polymorphic in the Limousin samples with minor allele frequencies >0.05 revealed significant associations between two candidate bovine imprinted genes and a range of important beef production traits: average daily gain, average feed intake, live weight, feed conversion ratio, residual feed intake and residual gain. These genes were the Ras proteinspecific guanine nucleotide releasing factor gene ( RASGRF1) and the zinc finger, imprinted 2 gene ( ZIM2). Despite the relatively small sample size used in these analyses, the observed associations with production traits are supported by the purported biological function of the RASGRF1 and ZIM2 gene products. These results support the hypothesis that imprinted genes contribute significantly to important complex production traits in cattle. Furthermore, these SNPs may be usefully incorporated into future marker-assisted and genomic selection breeding schemes.
    • Cattle Embryo Growth Development and Viabilty.

      Morris, D.G.; Grealy, M.; Leese, H.J.; Diskin, Michael G.; Sreenan, J.M. (Teagasc, 2001-06-01)
      A major problem for the cattle breeding industry is the high rate of early embryo loss which compromises reproductive efficiency and genetic improvement, resulting in serious financial loss to farmers. An important part of the Teagasc research programme in this area is the investigation of basic parameters of cattle embryo growth, development and viability during the critical period when most of the embryo loss occurs. We have now characterised this period of embryo development and to our knowledge, this is the first report describing the morphology, growth rate, protein content and metabolic activity of cattle embryos during this period. The main results are summarised here and detailed results have been published in the papers listed at the end of this report. Embryo growth rate and protein content increased exponentially between days 8 and 13 after fertilisation. Furthermore, there was a high rate of protein synthetic activity, energy and amino acid metabolism and signal transduction activity, all reaching a peak between days 8 and 13 after fertilisation. Because of the high rate of metabolic activity evident during this time it is likely that the embryos are very susceptible to environmental changes that have the potential to interfere with normal developmental mechanisms. The results arising from this project suggest that the critical period of early embryo loss in cattle may now be narrowed to a time window of day 8 to 13 rather than day 8 to 16 as presumed up to now. The main results are summarised.
    • Cease agricultural activity forever? Underestimating the importance of symbolic capital

      Conway, Shane Francis; McDonagh, John; Farrell, Maura; Kinsella, Anne (Elsevier, 2016-02-11)
      Similar to what is occurring on a global scale, Irish agriculture is populated by an older generation of farmers. Consequently, intergenerational family farm transfer is increasingly viewed as crucial to the survival, continuity and future sustainability of the family farm and agricultural sector. A review of existing research highlights how financial incentives that encourage succession and retirement from farming have stimulated little change in the behavioural intentions and attitudes amongst elderly farmers. Drawing on two previously disparate literature (transferring the family firm and transferring the family farm) and applying Pierre Bourdieu's concept of symbolic capital as a theoretical framework, this paper sets aside financial enticements and presents an insightful, nuanced analysis of the human factors that influence the process of transferring the family farm from the perspective of the senior generation. This research employs a multi-method triangulation design, consisting of self-administered questionnaires in conjunction with complimentary Problem-Centred Interviews, to acquire data on the complex psychodynamic and sociodynamic emotions involved in the process. The prominent themes to emerge from the empirical data are farmer's concerns regarding potential loss of identity, status and control upon transferring management and ownership of the family farm and retiring. Many older farmers appear to prioritise the building and maintenance of their personal accumulation of symbolic capital rather than ceasing agricultural activity. The paper concludes by suggesting that future policies and programmes encouraging family farm transfer must take into account the pervasiveness of symbolic capital and work within this structure to develop effective strategies that addresses the emotional well-being of elderly farmers.
    • A Census Atlas of Irish Agriculture

      Commins, P.; Lafferty, F.; Walsh, J.A. (Teagasc, 1999-08-01)
      Computerised mapping systems were developed to analyse agricultural census statistics and data from agricultural policy administration sources. The objective was to identify local geographical variations in the structure and trends in the agricultural economy by mapping the available information, principally at the level of the District Electoral Division (DED) and the Rural District (RD). There were 3,113 DEDs and 156 RDs in the analysis. The main database was the 1991 Census of Agriculture, the latest available. Some statistics are updated annually and where possible these were used in tabular form to trace the 1991- 1997 trends for Regional Authority areas. Conclusions: There are distinctive farming regions in the country whose boundaries span unevenly across county limits. These are undergoing different processes of change depending on their resource base, their responses to economic imperatives, and the policy environment. • Commercial farming has become increasingly associated with areas south and east of a line from Limerick to Dundalk. • It is likely that policies and trends post 2000 will further increase the differences in resource use between commercial farming and other areas.