• Concentrate Supplementation of Pasture for Beef Production

      French, Padraig; O'Riordan, Edward G.; O'Kiely, Padraig; Moloney, Aidan P (Teagasc, 2001-03-01)
      * Unsupplemented cattle offered a high grass allowance (18 kg (DM)/head/day), achieved 0.97 of the DM intake of a positive control offered concentrates ad-libitium. At a low grass allowance (6 kg/DM/head/day), there was no effect of supplementary concentrates on grass intake. At a medium (12 kg/DM/head/day), and high grass allowance, supplementary concentrates reduced grass intake by 0.43 and 0.81 kg/DM respectively per kg/DM concentrate offered. * Supplementary concentrates increased complete diet digestibility even though offering supplementary concentrates also increased total DM intake. Complete diet digestibility was higher than the additive values of the grass and concentrates. This would imply that the supplementary concentrates increased the grass DM digestibility. * Increasing the grass allowance increased plasma urea concentration; supplementary concentrates increased total dietary nitrogen intake and reduced plasma urea concentration. These findings suggest that the concentrate supplement enabled greater utilisation by rumen micro-organisms of the degradable nitrogen supplied by the grass. * Supplementing with concentrates increased carcass growth by 116 g/kg concentrate DM eaten whereas increasing the grass allowance increased carcass growth by 38 g/kg/DM grass eaten. The carcass weight response to concentrates of grazing animals was twice that of animals offered concentrates ad-libitum which gained 57 g carcass per kg concentrate DM eaten. * The relationship between carcass gain (Y) (kg/day) and supplementary concentrates (X) (kg/day) was quadratic (P< 0.001) and was best described by the equation: Y = -0.0099X2 + 0.1364X + 0.2459 (R2 = 0.60). The relationship between carcass gain (Y) (kg day-1) and grass intake (X) was also quadratic (P< 0.01) and was best described by the equation: Y = -43X2 + 275X + 133 (R2 = 0.48). Although there was a much larger (double) carcass growth response to supplementary concentrates than to additional grass DM eaten, increasing grass intake significantly increased carcass fat scores whereas offering supplementary concentrates did not. This would imply that relative to concentrates, autumn grass led to a change in the partitioning of energy from muscle towards subcutaneous fat. * As a strategy for increasing the performance of cattle grazing the type of autumn grass used in this study, offering supplementary concentrates offers more scope to improve animal performance than altering grass allowance. * The carbohydrate source of the three concentrates formulated to differ in rate of degradability did not alter rumen fluid pH, volatile fatty acid (VFA) concentration or the rate of grass DM or N degradation when grass supply was considered to be limiting or liberal. The autumn grass was apparently capable of buffering the effects of concentrate DM degradation rate which varied by up to two fold. * The rumen fluid parameters were more influenced by the pat-tern of grass intake than type of concentrate offered. Hence, there was no effect of concentrate type on animal performance.
    • Concentrate Supplements for Weanling and Finishing Steers

      Keane, Michael G. (Teagasc, 2003-03-01)
      Concentrates are a major cost element in feeding beef cattle in winter. Because of the need to retain finishing cattle until after specific dates to comply with retention periods for the draw-down of premia, feeding strategies must be flexible. The objectives of this study were to examine concentrate feeding strategies which would minimise concentrate feeding to weanlings and exploit compensatory growth, simplify feeding routines and improve the efficiency of concentrate utilisation in finishing cattle. Four experiments were carried out, two with weanlings and two with finishing cattle. • Weanlings fed outdoors (in sacrifice paddocks) in winter gained 13 kg more than those similarly fed indoors but by the end of the following grazing season the weight difference had decreased to 4 kg as a result of compensatory growth. • There was no response to an increase in protein level in the concentrate. • Feeding 2 kg/day of supplementary concentrates with silage in winter reduced silage intake by 0.4 kg dry matter (DM) and increased total DM intake by 1.27 kg/day. • The liveweight gain response in winter to 2 kg/day supplementary concentrates was 344 g/day or a total of 44 kg. By the end of the following grazing season this had declined to 14 kg (68% compensation) • The conversion ratio of concentrate DM to liveweight was about 5:1 at the end of winter but by the end of the following grazing season it was over 15 : 1. • Feeding a fixed total concentrate allowance to weanlings gave a better response when it was offered at a flat rate daily over the whole winter, or at a high rate over the first half of the winter, rather than when offered at a high rate over the second half of the winter. • Feeding a fixed total concentrate allowance ad libitum over the final part of the finishing period was superior to feeding it at a flat rate per day over the total period in terms of feed energy utilization. • There was no impairment in the efficiency of total feed energy utilization by delaying the feeding of a fixed concentrate allowance for up to 70 days after housing compared to feeding it immediately after housing. • Where animals are being finished over a 5-6 months period, rather than feeding concentrates at a flat rate throughout the whole period, it is better to delay introduction for 2-3 months and then offer concentrates ad libitum thereafter. • As the interval from housing to concentrate introduction increases, the response to concentrates fed ad libitum subsequently increases. • Although not reflected in carcass fat score, objective indicators of fatness were lower for animals fed concentrates ad libitum than for animals fed concentrates at a flat rate with silage.
    • Confirmation of co-denitrification in grazed grassland

      Selbie, Diana R.; Lanigan, Gary; Laughlin, Ronald J.; Di, H.J.; Moir, James L.; Cameron, K.C.; Clough, Timothy J.; Watson, C. J.; Grant, Jim; Somers, Cathal; et al. (Nature Publishing Group, 30/11/2015)
      Pasture-based livestock systems are often associated with losses of reactive forms of nitrogen (N) to the environment. Research has focused on losses to air and water due to the health, economic and environmental impacts of reactive N. Di-nitrogen (N2) emissions are still poorly characterized, both in terms of the processes involved and their magnitude, due to financial and methodological constraints. Relatively few studies have focused on quantifying N2 losses in vivo and fewer still have examined the relative contribution of the different N2 emission processes, particularly in grazed pastures. We used a combination of a high 15N isotopic enrichment of applied N with a high precision of determination of 15N isotopic enrichment by isotope-ratio mass spectrometry to measure N2 emissions in the field. We report that 55.8 g N m−2 (95%, CI 38 to 77 g m−2) was emitted as N2 by the process of co-denitrification in pastoral soils over 123 days following urine deposition (100 g N m−2), compared to only 1.1 g N m−2 (0.4 to 2.8 g m−2) from denitrification. This study provides strong evidence for co-denitrification as a major N2 production pathway, which has significant implications for understanding the N budgets of pastoral ecosystems.
    • Confirmation of the Dietary Background of Beef from its Stable Isotope Signature.

      Moloney, Aidan P; Bahar, Bojlul; Schmidt, Olaf; Scrimgeour, C.M. (Teagasc, 2009-11-01)
      Consumers are increasingly demanding information on the authenticity and source of the food they purchase. Molecular DNA-based technology allows animal identification, but without certification or a “paper-trail” but does not provide information about feed history or the production system under which the animal was reared. The stable isotopes of chemical elements (e.g.13C/12C, 15N/14N) are naturally present in animal tissue and reflect the isotopic composition of the diet. The overall aim of this project was to determine the feasibility of using the stable isotopic composition as an intrinsic, biochemical marker to gain information about feed components used in the production of beef. Factors likely to affect the isotopic signature such as source of tissue, duration of feeding and production systems were examined. It is expected that this highly innovative and original technique will permit the identification of country of origin and dietary history of beef and so greatly assist efforts to market Irish beef, particularly in lucrative European markets. Sequential sampling and stable isotope analysis of bovine tail hair and hoof revealed that the two tissues can provide a detailed and continuous record of animal dietary history. Because hair can be sampled repeatedly and noninvasively, we anticipate that this approach will also prove useful for the investigation of short-term wildlife movements and changes in dietary preferences.
    • Consumer attributes of farmhouse cheese and honey

      Cowan, Cathal; Murphy, Maurice; Daly, Eimear; Meehan, Hilary; Henchion, Maeve; Pitts, Eamonn; Delahunty, Conor; O'Reilly, Seamus; European Commission; CT95 -0360 (Teagasc, 2000-12)
      This study determined the ideal combination of attributes of farmhouse cheese (cheddar-type) and farmhouse honey for different consumer segments.
    • Consumer perceptions of meat quality

      Cowan, Cathal; Mannion, Michael; Langan, John; Keane, John B. (Teagasc, 1999-10)
      This study describes the policies in place for meat quality in six EU states, ascertains the consumer perception of quality for beef, pork and chicken and suggests how quality policy can be improved so it better meets the perceived needs of consumers.
    • Contamination of Beef Carcasses during Hide Removal and use of a Test Bacterial Decontamination System on Beef Hide

      McEvoy, John M.; Doherty, Alice M.; Sheridan, James J.; McGuire, Liam (Teagasc, 2000-12)
      In Ireland, the Abattoirs Act, 1988 (Veterinary Examination) (Amendment), 1998 (S.I. No. 6, 1998) empowers the ante mortem veterinary inspector to reject animals for slaughter or require slaughter under special conditions, based on the level of visible hide contamination. Special conditions for slaughter include reduced line speed, increased space between animals and increased use of workstation hygiene facilities. Since their introduction in Ireland, cattle regulations have become more stringent and at present, both category 4 and 5 animals are rejected. However, a procedure for shaving accumulated hardened faeces (faecal clods) from category 4 and 5 animals has been introduced into most abattoirs, enabling them to reach the cleanliness standard. The potential risk of pathogens surviving in faecal clods on the hide of animals at slaughter is not known. This study examined: 1. The relationship between livestock cleanliness categories and the amount of contamination on the resultant carcasses. 2. The difference in bacterial contamination on carcasses from category 4 animals dressed without increased use of workstation hygiene facilities and those dressed with increased use of hygiene facilities. 3. The survival of E. coli O157:H7 in faecal clods
    • Contested Ruralities: Housing in the Irish Countryside

      Pitts, Eamonn; Meredith, David; Duffy, Patrick J.; Walsh, Jim; Keaveney, Karen; Teagasc Walsh Fellowship Programme (Teagasc, 01/01/2007)
      The purpose of the study is to examine housing in the Irish countryside. Housing in the countryside has become an increasingly contested issue in Ireland due to processes of rural change. The realm of debate is around issues such as who has the right to live in the countryside and how traditional settlement patterns can be sustained into the future. The debate, which has many contributors from politics, media and interest groups, has suffered from a lack of large-scale empirical research. The release of a combination of data from the 2002 Census of Population (house type with type sewerage facility used) has allowed this research to establish the spatial extent of single rural dwellings, the most contested and least known about element of living in the Irish countryside. Using this data in conjunction with the study of local level housing processes, a greater understanding of rural housing in Ireland has been established.
    • Control and detection of food-borne pathogens

      Duffy, Geraldine; Cloak, Orla; Sheridan, James J.; Department of Agriculture, Food and the Marine, Ireland (Teagasc, Ballsbridge, Dublin 4, 1998-08)
      The objective of this study was to develop rapid methods for the detection of bacteria from food.
    • Control of Blown Pack Spoilage in Vacuum Packaged Meat

      Bolton, Declan; Moschonas, Galatios; Sheridan, James J.; Downey, Gerard; National Development Plan (Teagasc, 01/10/2009)
      Blown pack spoilage (BPS) represents a significant commercial loss to Irish meat processors. This research discovered that the organisms causing BPS are ubiquitous in the abattoir environment, making eradication very difficult. The risk of BPS is best managed through a process of regular treatment of plant and equipment with a sporicidal agent such as peroxyacetic acid, good hygiene to minimise carcass contamination and removal of the heat shrinkage stage during vacuum packaging as this activates the spores and reduces the time to spoilage.
    • Control of Cheese Microflora using Bacteriocins.

      Ross, R Paul; Hill, Colin; O'Keeffe, T.; McAuliffe, Olivia; Ryan, Maire; O'Connor, Paula M.; Freyne, T. (Teagasc, 2001-08-01)
      Bacteriocins are proteins, produced by some bacteria which are capable of inhibiting other bacteria. The overall aim of this project was the development and exploitation of bacteriocins such as Lacticin 3147 (produced by a food-grade microorganism), as biological tools to control the microflora of foods. Lacticin 3147-producing strains were evaluated for their ability to improve the microbial quality of a variety of dairy products and in particular, Cheddar cheese. The manipulation of cheese flora using bacteriocins should offer manufacturers greater control in the consistency and quality of the final product, in addition to improving its safety. In concert with these studies, Lacticin 3147 was studied in detail at the molecular level resulting in its biochemical and genetic analysis. These studies have demonstrated the complexity and uniqueness of this potent antimicrobial.
    • Control of escherichia coli 0157:H7 in beefburgers

      Bolton, Declan; Byrne, Catriona; Catarame, Terese; Sheridan, James J. (Teagasc, 2001-04)
      The inactivation of E. coli O157:H7 by heating, freezing, pulsed electric field, sodium lactate, lactic acid and citric acid, alone or in combination was investigated. The industrial process for beefburger manufacture did not significantly reduce E.coli O157:H7 numbers regardless of the burger recipe and method of tempering used. Fast freezing of the burgers (to -18°C in 30 minutes as opposed to 36 hours), pulsed electric field, sodium lactate, lactic acid and citric acid, individually and in combination, did not significantly reduce E. coli O157:H7 numbers when applied at different stages throughout the beef burger manufacturing process. Beefburger safety is therefore reliant on proper storage, handling and thermal processing in the domestic or catering kitchen. The lethal effect of thermal processing may be enhanced by the addition of sodium lactate to the burger during mixing. These results are presented and discussed.
    • Control of insect transmitted virus diseases in cereals and sugar beet.

      Kennedy, T.F.; Connery, J. (Teagasc, 2000-12-01)
      The objective of this investigation was to determine if, in a mild autumn when aphid numbers were high, the recommended aphicide treatments derived from earlier trial results were adequate to control BYDV in autumn-sown barley. Investigations on spring barley at Oak Park, 1990-1993, showed Barley Yellow Dwarf Virus (BYDV) can cause reductions in grain yield of up to 1.4 t/ha. These studies indicated that the risk of infection increased with lateness of sowing date. They also suggested that control of the disease might best be obtained by applying an aphicide at the 4-leaf stage of growth. The objectives of this investigation were to determine the growth stage at which aphicide should be applied in order to obtain best control of BYDV and to compare the effectiveness of systemic and contact aphicides in controlling the disease.Aphid numbers, species and infectivity with virus yellows were monitored in 20 beet crops between May and July over the period 1990-1999. Monitoring was undertaken to provide growers with an aphid-spray warning in order to minimise the risk of virus yellows and to establish aphid-thresholds which if exceeded would necessitate the spraying of crops with insecticide.
    • Control of Ovulation Rate in Beef Cattle.

      Morris, Dermot G.; Hynes, A.C.; Kane, Marian; Diskin, Michael G.; Sreenan, J.M. (Teagasc, 2002-06-01)
      Under intensive production systems, the greatest potential for effecting increases in production and economic efficiency in the beef cow herd lies in the possibility of increasing the frequency of twin births. Embryo transfer is technically a successful method of inducing twin births in cattle. While an embryo transfer approach is too costly to allow commercial twinning, it has been used to show that ovulation rate and not uterine capacity is the limiting factor in increasing the reproductive rate of the cow. While ovulation of one or more viable oocytes is central to normal reproduction, knowledge of the control of ovulation and of folliculogenesis on which ovulation depends, is limited. In spite of the fact that many follicles are subjected to the same endogenous hormonal environment and theoretically should all be capable of ovulating, only a tiny proportion do. While gonadotrophic hormones play a central role in ovarian follicle development and ovulation, their action at the ovarian level seems to be controlled by intra-ovarian factors. This intra-ovarian control of ovulation is thought to be exerted partly by the hormone inhibin and partly by other, as yet, unidentified compounds in follicular fluid. This project focused on identification and isolation of ovarian compounds involved in the control of ovulation rate, followed by immunisation against these compounds in order to study the effect on ovulation and the twin calving rates. The main results are summarised here and detailed results have been published in the papers listed at the end of this report.
    • Copper, Iodine and Selenium Status in Irish Cattle.

      Rogers, Philip (Teagasc, 2001-07-01)
      At 9 abattoirs throughout the state, samples of blood, liver and kidney were collected from the three cattle categories (cull dairy cows, cull beef cows and finished steers) at slaughter. In all, 2612 cattle were sampled for the following assays: copper (Cu), haemoglobin (Hb) and glutathione peroxidase (GPx, a selenoenzyme) on whole blood, inorganic iodine (I) in plasma, and Cu in liver and Selenium (Se) in a subset of liver and kidneys. The survey documented the overall status of Cu, I and Se in Irish cattle at slaughter and compared the trace element status of three categories of cattle. It also examined the effects of housing / season (late spring versus late autumn). I deficiency was the most prevalent mineral deficiency in all three bovine categories. Overall, in spite of whatever supplementation was being used preslaughter, 69% of samples had low (<50 µg/L) plasma inorganic I status (51% at the end of spring, 84% at the end of autumn). Overall, in spite of whatever supplementation was being used preslaughter, liver Cu status was low (<20 mg/kg DM) in 19% of samples (11% at the end of spring, 26% at the end of autumn). Liver Cu reflects Cu status more accurately than blood Cu. However, the relationships between Cu levels in liver and blood were poor in these data; it was not possible to predict a blood Cu level accurately from a given liver Cu level. Also, relative to liver levels, blood levels underestimated the extent of low Cu status by a factor of >2, with a wide range of error (0.9-2.6 times). However, as liver biopsy seldom is a practical option in commercial herds, blood tests usually are used for routine assessment of mineral status in live cattle. GPx levels in whole blood closely reflect blood Se status. In spite of whatever supplementation was being used preslaughter, blood GPx status was low (<40 iu/g Hb) in 11% of samples (4% at the end of spring, 16% at the end of autumn). In a subset of the data, blood GPx and Se levels in bovine kidney and liver had positive linear relationships but predictability was poor. A similar conclusion applies to levels of Se in liver and kidney. Also, liver Se correlated better with blood GPx (R2 = 0.443) than with kidney Se (R2 = 0.264). Cattle slaughtered off grass in late autumn had lower Cu, I and Se status than those slaughtered out of sheds in late spring. Finished beef steers and cull suckler cows had lower Cu and Se status than cull dairy cows. Liver and kidney had few high Cu or Se levels, indicating that current inputs of minerals do not pose a threat of toxicity to cattle, or to the human food chain. Mean PII levels in dairy cows were too low to pose a threat of excessive milk I levels for human consumption. Other research at Grange shows that trace element supplementation and trace element status in bovine blood, especially from dairy cows, improved nationally in recent years. However, this survey shows clearly that current national inputs of Cu, I and Se are inadequate to maintain normal trace element status in finished steers and cull (especially beef) cows at slaughter. This report concludes that current national inputs of Cu, I and Se are inadequate to maintain normal trace element status in finished steers and cull (especially beef) cows at slaughter, and from current inputs, the risk of Cu or Se toxicity to cattle, or to the human food chain, is minimal.
    • Cost reduction in bio-diesel production.

      Rice, B.; Frohlich, A.; Leonard, R. (Teagasc, 1999-05-01)
      As part of a programme to assess bio-diesel production from low-cost materials, the availability of waste oils and fats in Ireland and the EU was assessed, and the behaviour of their esters in vehicles was measured. The utilisation of beef tallow from BSE risk organisms was given special attention. Esterification of high-FFA tallow required the use of excess methanol and base catalyst. Acidification, followed by glycerol separation and secondary acid-catalysed esterification, brought ester yields up to acceptable levels. The high melting point of the ester restricted its use in vehicles to low proportions in mixes with mineral diesel. Fuels made up from low-cost esters behaved well in vehicle trials, even where there was a high level of dilution of the engine oil. The only problems arose from inadequate low-temperature properties and from suspended solids in the tallow ester. Within the EU, there are sufficient waste oils and fats available to greatly increase bio-diesel production. In Ireland, there is sufficient for a small production unit.
    • Costs of cereal production in Ireland and selected EU member states

      Kelly, P.W.; Shanahan, Ultan (Teagasc, 2001-02-01)
      This study investigates the costs of production and producers margins for barley and wheat production in Ireland and some other EU member states. Ireland is compared with Germany, Denmark, France (for wheat only), the UK and Italy. The data used was from the Farm Accounts Data Network (FADN) of the EU and relates to the calendar year 1998. It is derived from specialist producers in the Cereals, Oilseeds and Protein (COP) sector.
    • Cow welfare in grass based milk production systems

      Boyle, Laura; Olmos, G.; Llamas Moya, S.; Palmer, M.A.; Gleeson, David E; O'Brien, Bernadette; Horan, Brendan; Berry, Donagh; Arkins, S.; Alonso Gómez, M.; et al. (Teagasc, 2008-08-01)
      Under this project, aspects of pasture based milk production systems, namely different milking frequency and feeding strategies as well as genetic selection for improved fitness using the Irish Economic Breeding Index (EBI) were evaluated in terms of dairy cow behaviour, health, immune function and reproductive performance. Additionally, a typical Irish pasture based system was compared to one in which cows were kept indoors in cubicles and fed a total mixed ration for the duration of lactation in order to elucidate the perceived benefits of pasture based systems for dairy cow welfare.
    • Crop costs and margins and future cereal prices.

      Kelly, P.W. (Teagasc, 1999-09-01)
      This report summarises two pieces of research, one on Irish crop gross margins and the structure of direct costs for the period 1994-97 and the other on trends in world cereal prices to 2008 and their influence on the price of cereals in Ireland.
    • Current food safety priorities : report on the European Union risk analysis information network (EU - RAIN)

      Maunsell, Bláithín; Bolton, Declan; Downey, Gerard (Teagasc, 2006-04)
      An estimated 10 to 30% of the population in industrialised countries suffers food-borne illness annually, resulting in an unacceptable social (human suffering) and economic (health care and lost working days) cost. Risk analysis, a proactive preventative approach to food safety, was the focus of the European Union Risk Analysis Information Network (EU-RAIN) concerted action project. Funded by the European Commission, this project commenced in March 2003 and concluded in February 2006.