• Dairy cattle breeding objectives combining production and non-production traits for pasture based systems in Ireland.

      Berry, Donagh; Buckley, Frank; Dillon, Pat; Veerkamp, Roel F. (Teagasc, 2005-11-01)
      The objectives of this study were: 1) to estimate genetic (co) variances among body condition score, body weight, milk production, linear type traits and fertility, and 2) to investigate the presence of genotype by environment interactions for milk production, body condition score, and body weight, in Irish grass based seasonal calving herds. Genetic parameters were estimated from a potential 8928 primiparous and multiparous Holstein-Friesian cows over two years (1999 and 2000). Heritability estimates for body condition score (BCS) and body weight (BW) were found to be moderate to high; estimates ranged from 0.27 to 0.51 for BCS, and from 0.39 to 0.61 for BW. Heritability estimates for BCS change and BW change at different stages of lactation were all less than 0.11. Heritability for the linear type traits varied from 0.11 to 0.43. Phenotypic and genetic correlations between BCS and BW at the same stage of lactation were all close to 0.50 indicating that approximately 25% of the genetic and phenotypic variation in BW may be attributed to differences in BCS. Genetic correlations between BCS and milk yield tended to be negative (-0.14 to –0.51) and genetic correlations between BW and milk yield were close to zero (-0.07 to 0.09). However, the genetic correlations between BW adjusted for differences in BCS were positive (0.15 to 0.39). Genetic correlations between BCS and the fertility traits investigated were all favourable, indicating that cows with a superior genetic merit for BCS are on average likely to be served sooner, receive less services and have higher pregnancy rates. The genetic correlations between linear type traits and milk yield indicate that selection for milk production has resulted in taller, deeper cows that tend to be more angular and have less body condition. Genetically these cows are predisposed to inferior reproductive efficiency. Moderate genetic correlations were found between some of the linear type traits investigated and somatic cell count. A comparison of BCS, as recorded by Teagasc personnel (scale 1-5) and Holstein herd-book classifiers (scale 1-9) indicated consistency between the two sources. Phenotypic and genetic correlations of 0.54 and 0.86, respectively, were observed between the two measurement sources on the same animals. Genotype by environment interactions, were found for milk yield across different silage quality environments, and for BCS across different herd-year milk yield, concentrate, grazing severity and silage quality environments.
    • Dairy Ingredients for Chocolate and Confectionery Products.

      Keogh, M.K.; Twomey, Myra; O'Kennedy, Brendan; Auty, Mark; Kennedy, R.; O'Keeffe, James; Kelleher, Colin T (Teagasc, 2001-05-01)
      High free-fat, spray-dried powders were successfully produced at a lower fat content (40% rather than 56%) using ultrafiltration. Chocolates made from these powders had improved flow properties and superior quality. The stability, viscosity and firmness of toffees were improved by optimising the casein, whey protein and lactose levels of skim milk powders used in their manufacture.
    • Dairy Ingredients for the Baking Industry.

      Keogh, M.K.; Neville, Denis P.; STANTON, CATHERINE; Auty, Mark; Kennedy, R.; Arendt, Elke (Teagasc, 2001-08-01)
      Shortenings (baking fats), microencapsulated using dairy ingredients and milk protein hydrolysates, were produced for testing in a variety of baked products. The powders were evaluated for their functionality as powdered baking fats, as potential replacers of synthetic emulsifiers, as ingredients capable of improving baking performance or as potential health-enhancing ingredients. These studies provide the technology for the dairy industry to enter the specialised food ingredients sector with a siftable, non-greasy, free-flowing powdered fat for the baking industry.
    • Dairy Ingredients in Chocolate

      Keogh, M.K.; O'Kennedy, Brendan; Twomey, Myra; O'Brien, Nora M.; Kennedy, B.; Gorry, C. (Teagasc, 1998-09-01)
      The main objective was to assess and control the contribution of various ingredient components to chocolate behaviour and to optimise ingredients for specific chocolate applications. A key aim, therefore, was to understand the role of composition and particle structure and to produce spray dried powders with a functionality in chocolate as close as possible to roller dried powders. By demonstrating how the powder properties affect chocolate, it should be possible to control the functional properties of the powders to meet any powder or chocolate specification. Novel powder compositions indicated by this work should also be useful to chocolate makers. The ability to make chocolate under test conditions and to assess the role of milk powders or other ingredients has been put in place for the first time in Ireland. Previous knowledge of milk seasonality and of powder technology has provided a basis for understanding variations in milk powder functionality in chocolate. Spray dried powders with mean free fat values of 50 to 94%, particle sizes of 30 to 65 mm and vacuole volumes of 0.0 to 3.9 ml/100g were produced from milks of varying composition but under the same processing conditions. Advances were made in analysing powder structure through microscopy, particle size and occluded air measurement. Valuable new information has been generated on the changes in free fat, solid fat content, particle size and occluded air in powders. Explanations were provided for the first time for the complex effects of these properties on chocolate viscosity and yield value. This information will also make a positive contribution to other projects in the milk powder area. Good contacts have been established with multinational manufacturers and with producers of milk powder for chocolate.
    • Decision Support Systems For Disease Control in Winter Wheat.

      O'Sullivan, Eugene; Dunne, B.; Burke, J.J. (Teagasc, 2001-08-01)
      A leaf diagnostic test and a computer-based decision support system were evaluated for the control of diseases of winter wheat caused by Septoria spp. Fungicide programmes, as dictated by both methods, were compared with a standard routine programme, a reduced-rate programme and an unsprayed control from 1998 to 2000. In some instances fungicide programmes, dictated by leaf diagnostic tests, resulted in lower disease and higher yields than routine programmes but these were not consistent. Fungicide programmes, based on the computer-based decision support system, offered no advantages over routine programmes in terms of lower levels of disease, reduced numbers of fungicide applications or increased yields. Reduced-rate programmes, based on more frequent applications of low rates of fungicides, resulted in substantial savings of fungicides and in 1999 and 2000 better disease control and higher yields than routine programmes.
    • Design of automatic milking system for use in pasture-based systems

      O'Callaghan, Edmond J; White, J.; Hunt-Duffy, A.; Corcoran, B.; Esmonde, H. (Teagasc, 2007-01-01)
      A commercial vision system was successful in identifying target artificial teats in various and demanding scenarios, but the system is very prone to making false identifications. A robotic manipulator capable of the simultaneous handling of four milking cups has been designed. The end-effector profile is sufficiently compact to allow access between the rear legs of the cow while enabling full access to all four teats for application of milking cups. The positioning response of the end-effecter is satisfactory for accommodating small changes in teat position during milking cup application.
    • Developing sous vide/freezing systems for ready-meal components

      Tansey, Fergal; Gormley, Ronan T.; Carbonell, Serge; Oliveira, Jorge; Bourke, Paula; O'Beirne, David; Department of Agriculture, Food and the Marine (Teagasc, 2005-04)
      Sous vide cooking involves sealing raw or par-cooked food in a vacuumised laminated plastic pouch or container, cooking by controlled heating, rapid chilling and then re-heating for consumption. The chilled storage period is up to 21 days at 0 to 3oC. The recommended thermal process for sous vide products is 90oC for 10min or its time-temperature equivalent. Concerns about the safety of sous vide products, mainly due to the potential for temperature abuse in the chill chain, has prevented the widespread use of this technology. The role of the current project, therefore, was to investigate sous vide cooking followed by freezing, as a safe alternative to sous vide/chilling for 10 ready-meal components i.e. carbohydrates (potatoes, pasta, rice), vegetables (carrots, broccoli) and muscle foods (salmon, cod, chicken, beef and lamb).
    • Developing Sous Vide/Freezing Systems for Ready-Meal omponents

      Tansey, Fergal; Gormley, Ronan T.; Carbonell, Serge; Oliveira, Jorge; Bourke, Paula; O'Beirne, David (Teagasc, 01/04/2005)
      Sous vide cooking involves sealing raw or par-cooked food in a vacuumised laminated plastic pouch or container, cooking by controlled heating, rapid chilling and then re-heating for consumption. The chilled storage period is up to 21 days at 0 to 3oC. The recommended thermal process for sous vide products is 90oC for 10min or its time-temperature equivalent. Concerns about the safety of sous vide products, mainly due to the potential for temperature abuse in the chill chain, has prevented the widespread use of this technology. The role of the current project, therefore, was to investigate sous vide cooking followed by freezing, as a safe alternative to sous vide/chilling for 10 ready-meal components i.e. carbohydrates (potatoes, pasta, rice), vegetables (carrots, broccoli) and muscle foods (salmon, cod, chicken, beef and lamb).
    • Development and Application of Strategies to Generate Bacteriophage Resistant Strains for Use in Milk Fermentation Processes

      Ross, R Paul; Fitzgerald, Gerald F; Coffey, Aidan; Coakley, M.; O'Sullivan, Daniel (Teagasc, 1999-02-01)
      The objectives of this project were firstly, the identification of natural phage resistance systems for exploitation, secondly, the development of methodologies to utilise these systems to improve the bacteriophage resistance of starter strains for use in milk fermentation processes, and thirdly, the actual application of these methodologies to improving starter strains. The main conclusions were as follows: Three new natural plasmid (DNA)-associated bacteriophage resistance systems were identified at Moorepark. The detailed genetic makeup of the phage resistance plasmid (pMRC01) was elucidated. Bacteriophages currently evolving in the industrial cheese-making environment were monitored to facilitate the judicious choice of phage resistance systems for use in commercial starter cultures which can more effectively target the documented problematic phage types. Two highly virulent phages targeting important cheese starters were identified in the industrial cheese-making environment. A reliable food-grade method to facilitate the transfer of phage resistance systems to cheese-making starter strains was developed. This is based on bacteriocin immunity-linked phage resistance. Phage resistant cheese starter cultures were developed through natural selection and by molecular manipulation using phage resistance plasmids. The phage resistance plasmid pMRC01 was introduced to 31 cheese starter strains.
    • Development and Evaluation of Caseins/Caseinates for use as Ingredients in Food Products

      Mehra, Raj; Walsh, Daniel; O'Kennedy, Brendan; Kelly, Philip (Teagasc, 1998-09-01)
      The overall objective of this project was to investigate the effects of key processing steps in the industrial production of acid casein on the characteristics and functionality of sodium caseinate with particular emphasis on analytical/functionality testing and seasonal/lactational effects on the original milk. The main conclusions were as follows: The most significant result indicates that drying and concentration after washing of the acid casein curd are responsible for alterations in the structure of casein, which result in sodium caseinates with different properties. This was confirmed in the case of two acid casein plants investigated which showed similar results even though using different washing and drying technologies. This difference due to the drying step may be further amplified depending upon whether commercial sodium caseinate is manufactured from acid casein in the dried or wet curd state. The analytical and functional testing methodology adapted in our laboratory proved effective in predicting the effects of processing steps on the functionality of sodium caseinate. In particular, the ability to detect the presence of aggregate formation was particularly important. The database generated subsequently helped an acid casein manufacturer in modifying its process(es) to manufacture experimental sodium caseinate for specific food end-uses. Progress was greatly facilitated by the collaboration of individual manufacturers in the sourcing of problem samples from previously manufactured codes, and facilitating access to process plant during production. In a commercial application of the database, confidential work was undertaken on behalf of a client. Experimentally-produced sodium caseinate ingredients were evaluated using our adapted functionality testing methods and based on the results, the company was able to modify its process(es) to produce sodium caseinates with functionality for specific food end-users. It was concluded that while processing parameters in the production of acid casein can have a significant effect on the functional behaviour of the resultant sodium caseinate, the ability to assess this change in functional behaviour, through relevant functional testing, was equally important.
    • The Development and/or Validation of Novel Intervention Technologies to Assure Meat Food Safety

      Bolton, Declan; Byrne, Brian; Lyng, James G.; Downey, Gerard; Department of Agriculture, Food and the Marine, Ireland; Food Safety Authority of Ireland (Teagasc, 01/02/2007)
      This project was undertaken to fill some of the knowledge gaps in meat food safety from farm to fork. The data provide the scientific basis for a clean sheep policy to reduce the impact of fleece as a source of microbial contamination on ovine carcasses at the beginning of the slaughter process. At the other end of the slaughter-line, a polyurethane sponge swabbing technology was developed for ovine and bovine carcass sampling as required in 2001/471/EC and the new European Commission Hygiene Regulations. At the processing stages, studies were undertaken to determine the most effective media for the recovery and culture of Cl. perfringens cells and spores; the results were then applied to thermal inactivation studies on these bacteria. Thermal resistance data were also obtained for Bacillus cereus and a radio frequency cook for meat products was validated in terms of the destruction of Cl. perfringens and B. cereus cells and spores. Finally, an aerobiology study investigated the effectiveness of a range on measures to prevent air acting as a vector for bacterial dispersion in a meat processing plant.
    • The development and/or validation of novel intervention technologies to assure meat food safety

      Bolton, Declan; Byrne, Brian; Lyng, James G. (Teagasc, 2007-02)
      This project was undertaken to fill some of the knowledge gaps in meat food safety from farm to fork. The data provide the scientific basis for a clean sheep policy to reduce the impact of fleece as a source of microbial contamination on ovine carcasses at the beginning of the slaughter process. At the other end of the slaughter-line, a polyurethane sponge swabbing technology was developed for ovine and bovine carcass sampling as required in 2001/471/EC and the new European Commission Hygiene Regulations. At the processing stages, studies were undertaken to determine the most effective media for the recovery and culture of Cl. perfringens cells and spores; the results were then applied to thermal inactivation studies on these bacteria. Thermal resistance data were also obtained for Bacillus cereus and a radio frequency cook for meat products was validated in terms of the destruction of Cl. perfringens and B. cereus cells and spores. Finally, an aerobiology study investigated the effectiveness of a range on measures to prevent air acting as a vector for bacterial dispersion in a meat processing plant.
    • Development of a critical control step for E.coli 0157:H7 in pepperoni

      Duffy, Geraldine; Riordan, Denise C.; Sheridan, James J.; US-Ireland Co-operation Programme in Agriculture Science and Technology (Teagasc, 1999-10)
      Verocytotoxin producing Escherichia coli (VTEC) and particularly strains of serogroup O157, have emerged as food poisoning pathogens which can cause a severe and potentially fatal illness. The symptoms of VTEC infection include haemorrhagic colitis with bloody diarrhoea and severe abdominal pain. The infection may lead to renal failure as a result of haemolytic uraemic syndrome. Because of the severity of the illness and the low infectious dose, this pathogen is classed as a serious food safety issue. It is recommended by the United States Department of Agriculture that the production process for ready to eat foods such as fermented meats (pepperoni, salami etc.) should be capable of addressing a worst case scenario ie. the production process should be able to yield a log105.0cfu /g (105 cfu/g) reduction in numbers of E. coli O157:H7 on the raw meat. The aim of this study was to develop an industrially viable critical control step(s) which could be implemented into the pepperoni production process.
    • Development of a novel bulk packaging system for retail cuts of meat

      Allen, Paul; Doherty, Alice M.; Isdell, Emer (Teagasc, 1999-03)
      Meat colour is an important criterion in the appeal of meat to consumers at the point of sale. The bright red colour of fresh beef and lamb and the pinkish colour of fresh pork are due to the oxygenation of the myoglobin pigment when the meat is exposed to air. However, exposure to air over several days causes irreversible browning and rejection of the meat by consumers. The gaseous environment in which retail cuts are stored is therefore critical to ensure a good colour over the display life. Existing packaging systems do not have a sufficiently long storage life for the additional time required for exports from Ireland to the UK or continental Europe. The objective of this project was to develop a bulk packaging system for retail cuts that would have a sufficient shelf life to be used by the Irish industry to export retail ready cuts. In conclusion, a packaging system has been developed on a laboratory scale which is capable of extending the storage life of some beef cuts, lamb loin chops and pork loin chops. The display life of these after storage is comparable to fresh cuts. In order for this system to be commercialised it would have to be shown to work on a larger scale in a production environment.
    • Development of a Range of Encapsulated Milk Fat Products

      Keogh, M.K.; O'Kennedy, Brendan; Neville, Denis P.; Kennedy, B.; Gorry, C. (Teagasc, 1998-09-01)
      The aims of this research were to determine the effects of milk composition (fat, whey protein, lactose and salts) and process (homogenisation) factors on the formation of emulsions and microencapsulated powder particles and to relate these to the properties of the powder, especially susceptibility to fat oxidation. The effect of composition, using sodium caseinate and lactose on the production of high fat powders was also studied. Finally, new developments in microencapsulated milk powders were undertaken in collaboration with industry using sodium caseinate and lactose. Overall, the microencapsulation process should provide a technique to extend the shelf-life of sensitive fats and flavours and to produce high fat powders for a range of end-uses. The major components of the emulsions used to make the microencapsulated powders influenced fat globule diameter and stability, but the minor salt components also affected globule size and stability. Free flowing high fat (70%) powders with sodium caseinate and lactose as encapsulants were manufactured using a tall-form Niro spray dryer with fluidised beds. A flavoured ingredient using a by-product flavoured fat as the flavour agent was made using the same encapsulants. Microencapsulated powders were incorporated into baked goods as multi-functional ingredients. They increased loaf volumes and improved handling and processability of the dough, thereby extending the product range for fat and other dairy ingredients used for baking. Microencapsulated 80% fat blends were manufactured for biscuit formulations to overcome the handling problems associated with bulk fats. This sub-project also gave rise to a leading role in a EU FAIR project on the microencapsulation of fish oil for use in functional foods using milk components as the sole encapsulants.
    • Development of a Strategic Approach for a Single EU Beef Market

      Dunne, Liam; O'Connell, John J. (Teagasc, 2004-12-31)
      The MacSharry reforms of the CAP in 1992 initiated a major EU policy shift from product price support to a mix of lower prices and increased direct payments (DPs) as the primary method of supporting the income of cattle farmers. The reduction in the support price for beef and the introduction of new and increased DPs were phased in over a three year period up to 1995. In working paper No. 4 it was shown that cattle farmers in Ireland obtain the lowest beef prices in the EU but they also obtain the highest DPs per kilo of beef produced. The DPs are now a major source of revenue for cattle farmers in Ireland. Under the current system of administering DPs for beef, the value of DPs accruing to the individual cattle farmer is dependent on the possession of certain types of animals that are farmed within defined stocking densities. This paper evaluates how the changes have impacted on the margins for the cattle enterprise on the farms in the Teagasc, National Farm Survey (NFS) over the five year period 1993 to 1997. In particular the evaluation focused on: • the trends in the size of gross and net margins for a range of cattle systems • the trends in market based margins • the contribution of DPs to gross and net margins • the distribution of DPs among different types and size of cattle
    • Development of a Strategic Approach for a Single EU Beef Market. Extensification. An Analysis of National and Competitive Issues

      Dunne, Liam; Shanahan, Ultan; O'Connell, John J. (Teagasc, 31/12/2008)
      The economic merits of the two Options for extensification under Agenda 2000 were evaluated in relation to their ability to generate revenue and their impact on the competitiveness of Irish cattle farming.
    • Development of a Strategic Approach for a Single EU Beef Market: An Evaluation of Changes in the EU Intervention system and Labelling Regulations in Relation to Irish Cattle Prices.

      O'Connell, John J.; Dunne, Liam; Shanahan, Ultan (Teagasc, 01/01/2003)
      The intervention system for beef in the EU has undergone major changes since its inception. These changes were introduced because of changing circumstances in the EU beef market and because of cost factors and inefficiencies associated with and arising from the intervention system itself. While justified from these perspectives it can be said that from the perspective of beef producers the system has changed from being a mechanism which aimed at and operated to achieve a producer Guide Price which in turn was defined as “……..the price which it is hoped to attain on average on the Community market for all the quantities marketed during a given marketing year” (Com 370, July 1976) to one which has abandoned all efforts at achieving a desirable producer price and which provides at best very short term stabilisation of price at its market level. The aim of this paper is to trace the major changes which have occurred to the intervention system and the concomitant price achievement of beef in general in the EU and especially that of Irish beef. These changes together with other market and policy factors occurring on and since 1996 have combined to give a historically poor price performance for Irish beef which despite the growing importance of direct payments is still of major significance in the incomes and welfare of beef producers.
    • Development of an efficient milk production profile of the Irish dairy Industry

      Shalloo, Laurence; Dillon, Pat; Wallace, Michael; Dairy Levy Research Trust; European Union (Teagasc, 2008-07)
      Fluctuation around milk price will be the biggest factor that the dairy industry will experience over the next number of years. This fluctuation is being driven by fluctuation on the world dairy markets. In the past, when intervention was a much bigger feature of the CAP regime, the fluctuation in world markets had little effect on the EU price. This was because the Intervention system bought product from the market when prices were depressed and placed products on the world market when the price rose. This in effect meant that the CAP regime was having a regulatory effect on the world market as well as the EU markets. An example of the type of fluctuation observed on the world market can be gleamed from the Fonterra milk price in 2006-2007 ($4.50/kg (MS) milk solid) versus 2007-2008 ($7.90/kg MS). This corresponds to a 76% increase in price in 1 year. For the Dairy Industry in Ireland to prosper under these conditions all sectors will be required to be as efficient as possible from the farm, processing and marketing sectors. This report deals with; (1) Milk payment (2) Optimum milk production systems and (3) Seasonality of milk supply. (1) Milk payment systems in Ireland currently do not adequately reward high solids quality milk. Virtually all milk payment systems include a positive constant which reward the production of volume rather than the production of protein and fat kilograms. The A+B-C system of milk payment would adequately reward the production of protein and fat while at the same time correcting for the volume related processing costs. (2) Optimum systems of milk production will be built around the maximization of grass utilization in the future. Grazed grass is the cheapest feed that can be fed to dairy cows. Stocking rates nationally are 1.74cows/Ha around the milking platform and therefore when dairy farms are expanding they should do so by increasing stocking rate. The inclusion of supplementary feeds will reduce profitability for the vast majority of dairy farmers and could only possibly lead to increases in profitability when coupled increases in stocking rate. (3) Grass based systems while substantially reducing costs at farm level result in a seasonal milk supply profile. This results in a reduced capacity utilization of the milk processing facilities as well as restricted product port folio. However the production of Winter milk will lead to significant cost increases at farm level and should only be encouraged if the specific product produced would be sufficient to cover the additional costs associated with over winter production. Within spring calving systems milk payment systems should be used to encourage an efficient milk supply profile with a mean compact calving date of mid February.
    • Development of an Intensive Dairy Calf-to-Beef System and Associated Grassland Management.

      Keane, Michael G. (Teagasc, 2002-01-01)
      Over the years, beef production systems have been intensified and de-intensified in response to national and European Union policy changes. In the mid 1990s, a millennium target was set to produce 1000kg of beef carcass per ha in a dairy calf-to-beef system. This was in anticipation of possible future decoupling of premia from animals and the evolution of a production environment favourable to intensification. Results from a dairy calf-to-beef system for the years 1994 to 1997 are included in an earlier report (Keane and O’Riordan, 1998). This report presents the results of three production cycles of a two-year-old system (1996- 1998, 1997-1999 and 1998-2000) together with the findings from a comparison of three systems of grazing management. In cycle 1, Standard and Improved management options were compared. The differences between the two were that under Improved management, the yearlings were put to pasture about 3 weeks earlier than normal and they grazed the silage area until Standard turnout time, there were double the number of grazing paddocks in the rotation, and the animals remained at pasture later in autumn. Stocking rate was 2.76 animal units (yearling + calf) per ha. In cycles 2 and 3, stocking rate was 3.0 animal units per ha. Spring-born Charolais x Friesian steers were used in all cycles. Improved management increased liveweight gain of yearlings particularly in the early part of the grazing season but the Standard management animals exhibited compensatory growth subsequently which continued throughout finishing so that by slaughter there were no differences between the two management systems. In cycles 1, 2 and 3, total fertiliser N inputs were 217, 230 and 264 kg/ha, total silage yields conserved were 1.8, 1.6 and 1.7 t dry matter per animal unit, total lifetime concentrate inputs were 1057, 1042 and 1118 kg per animal and total number of days from arrival to slaughter were 736, 738 and 769, respectively. For cycles 1, 2 and 3, mean slaughter weights were 665, 660 and 644 kg, mean carcass weights were 360, 356 and 346 kg, mean carcass conformation scores were 2.77, 2.75 and 2.75 and mean carcass fat scores were 4.16, 4.19 and 4.15, respectively. Slaughter weight and carcass weight outputs per ha were 1833, 1980 and 1932 kg, and 992, 1068 and 1038 kg for cycles 1, 2 and 3, respectively, indicating achievement of the millennium target of 1000 kg/ha carcass output. Three systems of grazing management namely leader/follower, calves and yearlings mixed, and calves and yearlings grazed separately, were compared. Mean liveweight gains for the grazing season as a whole for the treatments as listed were 891, 948 and 1076 (s.e.d. 35.5) g/day for the yearlings, and 744, 702 and 671 (s.e.d 13.5) g/day for the calves. Leader/follower calves were 39 and 51 kg, respectively heavier than the mixed and separate calves at housing as weanlings. The corresponding values at turnout the following spring and at housing as yearlings were 42 and 52 kg, and 22 and 39 kg, respectively. There was no evidence of compensatory growth during the winter but some compensation did occur during the following grazing season. Having calves graze ahead of yearlings in the leader/follower system reduced housing weight of the latter by 18 and 34 kg compared with the mixed and separate treatments, respectively. There was no compensation during the following (finishing) winter at the end of which the corresponding slaughter weight differences were 19 and 36 kg resulting carcass weight differences of 12 and 21 kg. In the current policy environment where the optimum economic stocking rate is well below that which is technically possible and where it is no longer necessary to simultaneously optimise output per animal and output per ha, the challenge is to devise grazing strategies which maximise the performance of both calves and yearlings during the grazing season.