• Adding value to cull cow beef

      O'Donovan, Michael; Minchin, William; Buckley, Frank; Kenny, David; Shalloo, Laurence (Teagasc, 01/08/2009)
      This project addressed the prospects of increasing the value of cull cow beef and examined the potential of a number of different management and dietary strategies. In Ireland, the national cow herd contributes 350,000 animals to total beef production annually, which represents 22% of all cattle slaughtered (DAF, 2007). A dominant feature of beef production in Ireland is the disposal of cows from the dairy and beef industries, the time of year at which culling occurs influences the number of cows available for slaughter. Suitability of a cow for slaughter is generally not a consideration for dairy or beef farmers.
    • Alternatives to formic acid as a grass silage additive under two contrasting ensilability conditions

      Lorenzo, B. Fernandez; O'Kiely, Padraig (Teagasc, Oak Park, Carlow, Ireland, 2008)
      The effects of formic acid and four alternative additives on silage fermentation, in-silo DM losses and aerobic stability were compared in an experiment using both difficultto- ensile (DIFF) and easier-to-ensile (EASI) herbages. Both were ensiled in laboratory silos with either no additive or following the application of formic acid (FA; 850 g/kg) at 3 mL/kg herbage, Add-SaFeR® (ATF1) and GrasAAT® (ATF2), both based on ammonium tetraformate, at 4 mL/kg herbage, an antimicrobial mixture (MIX; potassium formate, sodium disulfite and sodium benzoate) at 3 g/kg herbage, or Ecosyl (LAB; Lactobacillus plantarum) at 3 mL/kg herbage. There were four replicates per treatment and the silos were stored for 132 days. DIFF silage made without additive was poorly fermented. All additives increased the extent and improved the direction of DIFF silage fermentation, and reduced in-silo losses. However, MIX did not reduce butyric acid concentration and increased the extent of aerobic deterioration. LAB had a smaller effect on fermentation and in-silo losses than FA. With EASI silages, all additives restricted the extent of fermentation and improved fermentation quality, with the latter effect being smaller than for DIFF silages. LAB promoted a particularly homolactic fermentation but subsequently increased aerobic deterioration. In both DIFF and EASI silages additive treatment improved in vitro digestibility. It is concluded that only ATF1, ATF2 and MIX were as effective as FA at improving silage preservation and reducing in-silo losses with both DIFF and EASI herbages. However, ATF1 and ATF2 were superior in reducing the apparent extent of proteolysis and MIX was slightly less effective at reducing the activity of saccharolytic Clostridia.
    • Aspects of management options for pasture-based dairy production stocked at two cows per hectare

      Humphreys, James; Lawless, Aidan; Healy, M.; Boland, A.; McNamara, K. (Teagasc, 2007-01-01)
      White clover in association with Rhizobium bacteria have the capacity to fix or convent atmospheric N into plant available N. This can make a considerable contribution to sward productivity. One of the objectives of this experiment was to determine the upper carrying capacity of grass-white clover swards receiving 90 kg fertilizer N/ha. A second objective was to examine the impact of grass-clover swards on mineral-N in the soil and losses of nitrate-N from soil to drainage water during the winter. This experiment was conducted at Solohead Research Farm. There were three treatments: (i) A grass-only treatment (FN) stocked at 2.0 cows per ha in 2003 and 2.2 cows per ha during 2004, 2005 and 2006. This treatment received an average of 226 kg per ha of fertilizer N per year during these years. (ii) A grass-clover treatment (WC) stocked at the same rates as FN and received an average of 90 kg per ha of fertilizer N per year during the experiment. (iii) A grass-only treatment (CC) that was gradually converted over to grass-clover during the experiment and stocked at 2.0 cows per ha throughout the experiment. Fertilizer N input was gradually lowered from 150 kg per ha in 2003 to a target of 90 kg per ha in 2005 and 2006.
    • 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.
    • Changes in yield and composition of barley, wheat and triticale grains harvested during advancing stages of ripening

      Stacey, P.; O'Kiely, Padraig; Hackett, Richard; Rice, B.; O'Mara, Frank P.; Teagasc Walsh Fellowship Programme (Teagasc, Oak Park, Carlow, Ireland, 2006)
      This study involved an evaluation of the changes in grain yield, nutritive value, ensilability and harvesting losses of intensively managed winter cereals harvested during the advancing stages of ripening. Five cereal crops (barley cv. Regina and wheat cv. Madrigal in 2001; barley cv. Regina, wheat cv. Falstaff and triticale cv. Fidelio in 2002) were assessed. Twenty plots per crop were arranged in a randomised complete block design, with five times of harvest (four for barley in 2002) and four replicate blocks per harvest. Dry matter (DM) yields changed relatively little between harvest dates, but fresh yields declined (P < 0.001) over time due to the moisture loss associated with ripening. Time-course changes in indices of nutritive value, such as concentrations of crude protein, starch and ash, and organic matter digestibility, were relatively small and did not follow a consistent pattern. Ensilability indices, such as DM and watersoluble carbohydrate concentrations and buffering capacity, indicated that satisfactory fermentations were likely if such crops were ensiled; buffering capacity, generally declining with advancing maturity. Harvesting losses were not clearly related to growth stage at harvest. It is concluded that winter cereal grain (barley, wheat and triticale) DM yields and quality were relatively constant as ripening progressed from DM concentrations of around 550 to >800 g/kg.
    • Comparative growth and management of white and red clovers

      Black, Alistair D; Laidlaw, A.S.; Moot, D.J.; O'Kiely, Padraig (Teagasc, Oak Park, Carlow, Ireland, 2009)
      The aim of this paper is to provide the underpinning scientific basis for the optimum management of white and red clovers. Critical morphological and canopy characteristics which influence the yield and persistence of white and red clover in swards, and how management factors (choice of cultivar, defoliation and nitrogen (N) fertilizer) modify these are considered. Canopy development is vitally important as it determines the extent to which a) light is intercepted for photosynthesis needed for growth and b) the base of the sward is deprived of the red component in daylight, inhibiting branching of stolons and crowns in white and red clover, respectively. The role of cultivar, defoliation and N fertilizer in determining yield and persistence of the two legumes, mainly in mixtures with grass, are discussed principally in terms of morphological development and exploitation of light. It is concluded that optimum management for grass/white clover places emphasis on building up stolons and maximising contribution of clover leaf area to the upper layers of the mixed canopy and, while red clover is more competitive to grass than white clover, that benefit is lost when a grass/red clover sward is grazed.
    • Comparison of a Calan gate and a conventional feed barrier system for dairy cows: feed intake and cow behaviour

      Ferris, C.P.; Keady, Tim; Gordon, F.J.; Kilpatrick, D.J. (Teagasc, Oak Park, Carlow, Ireland, 2006)
      There is little published information on comparisons of individual and group feeding systems for dairy cows. Twenty-four dairy cows were used in a three-period incompletely balanced, change-over design study, to examine food intake and feeding behaviour of dairy cows offered their food via group-access electronic Calan gates, or via a conventional feed-barrier system. The food offered was in the form of a complete diet, and comprised grass silage and concentrates (60:40 dry matter (DM) basis). With the conventional feed-barrier system a maximum of eight animals were able to feed at any one time, while the Calan-gate system allowed a maximum of three animals to feed at any one time. Method of offering the ration had no effect on daily DM intake. During the 8-h period after animals were given access to fresh food, the mean number of animals feeding at any one time was 5.4 and 3.0 for the conventional and Calan-gate systems, respectively, while total intake over this period was 11.0 and 9.2 kg DM per cow, respectively. When access to feed was restricted by the use of Calan gates, animals responded by increasing their intake rate. It is concluded that total DM intake was unaffected by the use of a group Calan-gate feeding system as animals modified their feeding behaviour to maintain food intake.
    • Comparison of growth curves of three strains of female dairy cattle

      Berry, Donagh P.; Horan, Brendan; Dillon, Pat (Cambridge University Press, 2005-04)
      The objective of the present study was to compare growth curves for live weight (LW) and body size of three strains of female dairy cattle reared under common environments in Ireland. One strain (HP) was selected from a predominantly North-American/European Holstein-Friesian genetic pool selected for high milk production. The second strain (HD) represented a predominantly North-American/European Holstein-Friesian genetic pool selected for high milk production but with greater selection emphasis on functional non-production traits. The third strain (NZ) consisted of New Zealand Holstein-Friesian females of high genetic merit for profitability in New Zealand. The data consisted of 99 animals (33 animals in each strain) with records on LW, length, girth and height from birth to a minimum of 594 days of age. The von Bertalanffy growth function was fitted to each animal's records separately and least-squares analyses were used to investigate the effect of strain on birth LW/body size, parameters of the growth function and average daily gains. Average mature live weight of the HD animals (591 kg) was significantly larger than that of the HP (566 kg) or NZ (543 kg) strain; the HD strain matured more slowly. The HD (134 cm) and HP (135 cm) strains were significantly taller than the NZ (128 cm) strain. Although the data set was relatively small there are indications that dairy females of North-American genetic origin were heavier at birth, grew faster, and were heavier and taller at maturity than dairy females of New Zealand origin.
    • Comparison of herbage yield, nutritive value and ensilability traits of three ryegrass species evaluated for the Irish Recommended List

      Burns, G. A.; O'Kiely, Padraig; Grogan, D.; Watson, S.; Gilliland, T. J. (Teagasc (Agriculture and Food Development Authority), Ireland, 2016-01-13)
      This study examined 169 of the newest varieties of three ryegrass species, perennial (Lolium perenne L.), Italian (Lolium multiflorum Lam.) and hybrid (Lolium boucheanum Kunth), from Recommended List trials in Ireland. The traits examined were yield, dry matter concentration, three nutritive value traits (in vitro dry matter digestibility, water-soluble carbohydrate on a dry matter basis and crude protein concentration) and two ensilability traits (buffering capacity and water soluble carbohydrate concentration on an aqueous phase basis). Varietal monocultures of each species underwent a six cut combined simulated grazing and silage management in each of two years following sowing. Perennial ryegrass yielded less than both other species in one-year-old swards, but less than only Italian ryegrass in two-year-old swards, but generally had the higher in vitro dry matter digestibility and crude protein values. Italian ryegrass displayed the most favourable ensilability characteristics of the three species with perennial ryegrass less favourable and hybrid ryegrass intermediate. Overall, despite the high yields and favourable nutritive value and ensilability traits recorded, the general differences between the three ryegrass species studied were in line with industry expectations. These findings justify assessing the nutritive value and ensilability of ryegrass species, in addition to yield, to allow farmers select species that match farming enterprise requirements.
    • Conservation characteristics of baled grass silages differing in duration of wilting, bale density and number of layers of plastic stretch-film

      Keles, G.; O'Kiely, Padraig; Lenehan, J.J.; Forristal, P.D. (Teagasc, Oak Park, Carlow, Ireland, 2009)
      The effects of duration of wilting, bale density and number of layers of plastic stretchfilm used to wrap bales on the conservation characteristics of baled grass silage was investigated. Grass from the primary growth of a Lolium perenne dominant sward was wilted for 24, 48 or 72 h. For each duration of wilting, 54 cylindrical bales (1.2 m nominal diameter) were made with the baler at a high or low density setting for alternate bales. Bales were wrapped with 2, 4 or 6 layers of plastic stretch-film and stored outdoors for 295 days. Two layers of plastic stretch-film resulted in inferior preservation, lower digestibility and extensive mould growth and deteriorated silage. Substantial improvement occurred to each of these characteristics from applying four layers of stretch-film (P<0.05), while six layers of stretch-film brought little further improvement. When four or six layers of stretch-film were used, extensive wilting restricted fermentation and improved the standard of preservation with the apparently difficult-to-preserve herbage used in this experiment. However, under the anaerobic conditions provided by four or six layers of stretch-film neither progressive wilting nor bale density had a major effect on digestibility, or the extent of surface mould growth or deteriorated silage. It can be concluded that a minimum of four layers of conventional black plastic stretch-film were required to achieve suitably anaerobic conditions, and that the additional benefits from six layers were small. Once anaerobic conditions were achieved, extensive wilting improved the conservation characteristics of baled grass silage made from a difficult-to-preserve crop, whereas bale density had little impact.
    • Conservation characteristics of grass and dry sugar beet pulp co-ensiled after different degrees of mixing

      Cummins, B.; O'Kiely, Padraig; Keane, Michael G.; Kenny, David A. (Teagasc, Oak Park, Carlow, Ireland, 2007)
      The objective of this experiment was to quantify the effects of the degree of mixing of dry molassed sugar beet pulp (BP) with grass on silage conservation characteristics. Herbage from a timothy (Phleum pratense) sward was precision chopped and treated with a formic acid based additive (3 l/t grass). Units of 50 kg grass, without or with 2.5kg BP were randomly allocated among four replicates on each of seven treatments. The treatments were (1) no BP (NONE), (2) BP evenly mixed through the grass (EVEN), (3) BP evenly mixed through the lower 25 kg grass (LOWH), (4) BP evenly mixed through the lower 12.5 kg grass (LOWQ), (5) 0.625 kg BP mixed through the top 25 kg grass and 1.875 kg SBP mixed through the lower 25 kg grass (25/75), (6) BP placed in 0.5 kg layers beneath each 10 kg grass (LAYR), and (7) BP placed in a single layer under all of the grass (BOTM). Laboratory silos were filled and sealed, and stored at 15 °C for 163 days. Effluent was collected and weighed from each silo throughout the ensilage period. At opening, silage composition and aerobic stability measurements were made. Total outflow of effluent was reduced (P<0.001) by the addition of BP; LAYR had a greater effect (P<0.001) than any of the other treatments. Effluent dry matter (DM) concentration was highest (P<0.05) for BOTM and lowest (P<0.01) for NONE. All treatments underwent similar lactic-acid dominant fermentations. Incorporation of BP with grass increased silage DM concentration (P<0.001), in vitro DM digestibility (P<0.05) and water soluble carbohydrate (P<0.001) concentration and reduced acid detergent fibre (P<0.001) concentration. Aerobic stability was similar across treatments and aerobic deterioration at 192 h was higher (P<0.05) for LOWQ, 25/75, LAYR and BOTM than for NONE. In conclusion, the incorporation of BP increased silage DM digestibility but had relatively little effect on fermentation or aerobic stability. Placing BP in layers gave the largest and most sustained restriction in effluent output.
    • Development of an efficient milk production profile of the Irish dairy Industry

      Shalloo, Laurence; Dillon, Pat; Wallace, Michael (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.
    • The economics of reseeding on a dairy farm

      Shalloo, Laurence; Creighton, P.; O'Donovan, Michael (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
      Herbage production and utilization on Irish dairy farms is well below its potential. A number of factors influence herbage production and utilization, not least the level of annual reseeding (introduction of a new grass ley) on the farm. The potential farm performance is reduced by old permanent pasture due to the combined effects of reduced out-of-season herbage production and lower overall herbage yield when compared to perennial ryegrass. Based on the sales of grass seed, it is estimated that approximately 2% of the land area on dairy farms in Ireland is reseeded annually. This has created a situation where the overall percentage of perennial ryegrass in sward is low. The objective of the present study was to investigate the economic benefits of reseeding through simulating the consequences of reseeding different proportions of the farm on an annual basis. Four levels of an annual reseeding programme were evaluated: 1%, 5%, 10% and 15% of the farm reseeded annually; evaluated at three milk prices (20 c/L, 27c/L and 33 c/L). Increasing the level of reseeding resulted in an increase in total and seasonal herbage production and, when accompanied by an increased stocking rate, increased herbage utilization. At a milk price of 27 c/L, farm profitability was €20 764, €24 794, €30 073 and €33 515 on a 40 ha farm when 1%, 5%, 10% and 15%, respectively, of the farm was reseeded annually. Irrespective of milk price, increasing the level of reseeding had a positive effect on profitability and the highest gain was achieved at the highest milk price. Sensitivity analysis showed that sward persistency and, to a lesser extent, herbage utilization had significant effects on the benefit from reseeding.
    • Effect of autumn/spring nitrogen application date and level on dry matter production and nitrogen efficiency in perennial ryegrass swards

      O'Donovan, Michael; Delaby, L; Stakelum, G; Dillon, Pat (Teagasc, 2004)
      The influence of autumn/spring N-application date and level on grass dry matter (DM) production in spring and on N uptake, recovery and efficiency were examined over 3 years (1998, 1999 and 2000, identified as Year 1, 2 and 3, respectively). Seven N-application dates were investigated in years 2 and 3 while four application dates were investigated in Year 1. The application dates were 21 October (T1), 11 November (T2), 2 December (T3), 23 December (T4), 12 January (T5), 3 February (T6) and 23 February (T7). Three N-application rates (kg N/ha) were used: 30 (N30), 60 (N60) and 90 (N90) plus a zero-N control (N0). Herbage DM yields were determined on: 18 March (H1) and 8 April (H2). Two herbage masses (HM) (40 mm above ground level) at initial Napplication date were investigated: a high HM (HHM) of 500 kg DM/ha and a low HM (LHM) of 100 kg DM/ha. The HM at initial N-application date in Year 1 was HHM, in Year 2 LHM and in Year 3 both HHM and LHM. There was a significant effect of Year (P<0.001), HM (P<0.001), N-application date (P<0.001) and N level (P<0.001) on DM production at both H1 and H2. At H1 there was a significant interaction between N-application date and level for DM production. N-application date had a significant (P<0.001) effect on N recovery at both H1 and H2. The highest N recovery rate at the two harvest dates was at T5, while the lowest was at T1 and T2. At H1 and H2 there was a significant effect (P<0.001) of application date on response to applied N. The responses were 7.5, 8.0, 8.3, 12.0, 15.7, 7.3 and 5.6 (kg DM/kg N) (s.e. 1.88) for T1 to T7,respectively, at H1, while the corresponding values at H2 were 10.3, 8.7, 6.1, 15.2, 17.6,11.4 and 15.1 (s.e. 1.88). At H2 the response to applied N was 15.6, 11.5 and 9.1 (kg DM/kg N) for N30, N60 and N90, respectively (P<0.05). Regression analysis indicated that highest DM production was achieved with T5 for both H1 and H2 harvest dates, while the lowest responses were associated with T1, T2 and T3 application dates.
    • The effect of different levels of spring grass supply and stocking rate on the performance and intake of cows in early lactation

      O'Donovan, Michael; McEvoy, Mary; Kennedy, Emer; Delaby, Luc; Murphy, John (Teagasc, 2008-11-01)
      Grazed herbage can supply nutrients to dairy cows at a lower cost than alternative feeds (Shalloo et al., 2004). Therefore, the objective of pasture-based systems must be to maximize the proportion of grazed grass in the diet of the dairy cow (Dillon et al., 2005). The extension of the grazing season into the early spring period can be facilitated by ceasing grazing of pastures earlier in autumn which allows grass to accumulate, thereby ensuring an adequate herbage supply in early spring when animal demand exceeds grass growth/supply (O’Donovan, 2000). Grazing pastures in early spring has previously been shown to increase herbage utilization and condition swards for subsequent grazing rotations (O’Donovan et al., 2004; Kennedy et al., 2006).
    • The effect of floor type in farrowing crates on piglet welfare

      Lewis, Eva; Boyle, Laura; O’Doherty, J.V.; Brophy, P.; Lynch, P Brendan (Teagasc (Agriculture and Food Development Authority), Ireland, 2005)
      The effect on piglet welfare of different combinations of flooring in the sow and piglet areas of farrowing crates was examined. One hundred and three multiparous sows were housed, from one week pre-farrowing through farrowing and lactation to weaning, in farrowing crates with one of five flooring combinations: SS – slatted steel in both the sow and piglet areas of the crate; SP – slatted steel sow flooring and plasticcoated expanded metal for the piglets; AP – slatted steel (with a checker-plate panel)sow flooring and plastic-coated expanded metal for the piglets; CP – expanded cast iron sow flooring and plastic-coated expanded metal for the piglets; PP – plastic-coated woven wire sow flooring and plastic-coated expanded metal for the piglets. The number of litters assigned to SS, SP, AP, CP and PP were 27, 23, 17, 18 and 18, respectively. All piglet areas had a water-heated pad. Piglets were examined for lesions, scored from zero to three according to severity, at six locations on each foot and at seven locations on each limb during the suckling period. Addition of scores at each location yielded a foot and limb lesion score. In addition, the proportion of piglets in a litter affected by at least one injury was calculated for each of the following: the carpal joints, coronets, accessory digits, footpads. Piglet behaviour was recorded for 2 h, between 1330 and 1630, at 24 h after birth. Litters were weighed at birth and at weaning, and all deaths were recorded during the suckling period. SS litters had higher foot and limb lesion scores (P < 0.001). In addition, a greater proportion of piglets in SS litters were affected by at least one injury to the carpal joint, coronet, accessory digit and footpad (P < 0.001). SP piglets were active on the heatpad in more observations than AP piglets (P < 0.05). PP piglets were inactive in other areas of the pen in more observations than SS piglets (P < 0.05). There was no effect of treatment on piglet weight gain or mortality. It is concluded that the use of slatted steel in piglet areas of farrowing crates cannot be recommended because of injuries to piglets’ feet and limbs. The combination of slatted steel in the sow area and plastic-coated expanded metal in the piglet area encourages use of the heatpad. However, use of plastic-coated woven wire in the sow area encourages piglets to use this area which puts them in danger of being overlaid by the sow.
    • Effect of genetic group and feed system on locomotion score, clinical lameness and hoof disorders of pasture-based Holstein–Friesian cows

      Olmos, G.; Boyle, Laura; Horan, Brendan; Berry, Donagh P.; O'Connor, P.; Mee, John F; Hanlon, A. (Cambridge University Press, 2009-01)
      The aim of the present study was to determine the effect of the genetic group of the Holstein–Friesian (HF) and pasture-based feeding system (3 × 2 factorial arrangement) on locomotion score (six gait aspects scored from one to five), clinical lameness and hoof disorders within a seasonal calving milk production system. The three genetic groups compared had an average Economic Breeding Index (EBI) value of 40, 70 and 80: representing the Irish national average genetic merit (LOW-NA), high EBI genetic merit of North American ancestry (HIGH-NA) and high EBI genetic merit of New Zealand ancestry (HIGH-NZ), respectively. Two feed systems were compared: a high grass allowance, low-concentrate system typical of spring-calving herds in Ireland (control) and a high-concentrate system. Data from 126 cows collected across a complete lactation period were analysed using generalised estimating equations and survival analysis. Genetic group of HF had a significant effect on locomotion score, clinical lameness and hoof disorders. Higher EBI cows (HIGH-NA and HIGH-NZ) had lower hazard of poor locomotion score in some gait aspects (e.g. spine curvature) and lower odds of clinical lameness in the first 200 days post-calving (Odds ratios 0.08 and 0.24, respectively, relative to the LOW-NA) and some hoof disorders (e.g. traumatic lesions) compared with LOW-NA cows. The high-concentrate feed system showed a higher incidence and severity of digital dermatitis (P < 0.01). Thus, high EBI cows have better locomotion, fewer cases of clinical lameness and less-severe hoof disorders (i.e. digital dermatitis, white line disease and traumatic lesions) than low EBI cows. These findings have important implications for cow welfare and productivity.
    • The effect of grass genotype and spring management on the nutritive value of mid-summer ryegrass swards

      O'Donovan, Michael; Hurley, Grainne; Gilliland, Trevor (Teagasc, 2008-07-01)
      The objective of this project was to investigate the environmental, morphological and management factors that control reproductive initiation and development in Lolium perenne L. (perennial ryegrass) and their influence on mid-season sward quality. These factors were assessed on eight perennial ryegrass cultivars through spaced plant and plot studies. The first part of this project determined the effects of meteorological conditions and latitude on reproductive initiation and ear emergence of cultivars over two consecutive years. It was concluded that the critical day length requirement for reproductive initiation varies between perennial ryegrass cultivars and is independent of latitude and the normal range of conditions. Using this information a strong correlation (r2 = 0.94) was found between the critical day length for ear initiation and the ten year standardised ear emergence dates of the cultivars. This correlation was sufficiently robust to predict the critical initiation date for any perennial ryegrass cultivar on a UK recommended list or on the EU common catalogue by using their heading dates from the UK Plant Breeders Rights trials at Crossnacreevy. Large variation was observed for secondary initiation and re-heading between cultivars of similar and varying maturity, which is a major factor reducing mid-season sward quality. The propensity for initiation of re-heading was strongly influenced by the severity of defoliation (intense to very lax), but there was also evidence to suggest that critical day length post-solstice, may determine the latest date when further reproductive initiation could occur. Differences in plant growth modes were clearly evident as the sward structure, plant morphology and nutritive compositions differed significantly between cultivars during the mid-season. Defoliation management also significantly affected mid-season sward structure, morphology and nutritive composition. While the effect of defoliation height on the sward physical and chemical compositions was inconclusive, an intensive (30 mm) defoliation resulted in plants returning to a vegetative growth mode earlier compared to a lax (60 mm) defoliation treatment. It was observed that defoliation at a critical growth stage can significantly affect subsequent sward structures. Delaying initial spring defoliation resulted in a greater leaf proportion and swards of greater herbage quality in the plot study. This study, therefore, established the need for more detailed evaluation of cultivars by national testing authorities to allow farmers to select cultivars for grazing use that will optimise animal intake and performance.
    • The effect of Holstein-Friesian genotype and feeding system on selected performance parameters of dairy cows on grass-based systems of milk production in Ireland

      Dillon, Pat; O’Connor, Paula M.; McCarthy, S.; Shalloo, Laurence; Linnane, M.; Berry, Donagh P.; Buckley, James F.; Mee, John F; Horan, Brendan (Teagasc, 2006-01-01)
      The overall objective of this project was to assess, the effect of strain of Holstein-Friesian dairy cow, pasture-based feed system (FS) and their interaction on animal performance in terms of milk productivity and lactation profile, body weight (BW), body condition score (BCS), feed intake and energy balance (EB), reproductive performance and overall economic profitability.
    • Effect of Holstein–Friesian genetic group on peripartum and early lactation haematological and acute phase proteins profiles, health and fertility

      Olmos, G.; Boyle, Laura; Horan, Brendan; Berry, Donagh P.; Sayers, Riona; Hanlon, A.; Mee, John F (Cambridge University Press, 2009-07)
      Pasture-based Holstein–Friesian cows from three genetic groups differing in the Irish ‘Economic Breeding Index’ (EBI) value and genetic background, namely North-American (NA) national average EBI genetic merit (LOW-NA, n542), North-American high EBI genetic merit (HIGH-NA, n542) and New Zealand (NZ) high EBI genetic merit (HIGH-NZ, n542), were studied. These genetic groups have been selected in different environments: pasture for NZ and confinement for NA. The objective was to determine the effect of genetic group on haematological and acute phase proteins profiles (white blood cell (WBC) counts, red blood cell (RBC) counts, acute phase proteins: serum amyloid A (SAA) and haptoglobin), health (rectal temperature (RT), clinical mastitis (CM) and somatic cell score), calving performance (stillbirth, calving assistance) and post-partum reproductive parameters (endometritis and ovarian cyclicity). Blood sampling and data recording took place 3 weeks pre-calving up to 7 weeks post-calving. Linear mixed models, logistic regression and generalised estimating equations were used for data analysis. HIGH-NZ animals had the highest ( P,0.05) RBC mean corpuscular volume (50.0 fl), exhibited a different WBC distribution pattern ( P,0.05) and had the lowest ( P,0.05) mean RT (38.48C) for the first 10 days post-calving. These findings suggest enhanced reticulocyte turnover, peripartum response mechanisms and thermoregulation in the HIGH-NZ compared to the other two genetic groups. LOW-NA animals had the highest SAA peak throughout the peripartum period (55.12 mg/l, P,0.05) and a tendency for higher somatic cell scores ( P,0.10) in early lactation. The HIGH-NA animals had the lowest incidence of udder quarter milk sample bacteria at calving, suggesting better udder health when commencing lactation. No differences were detected between genetic groups in calving performance, post-partum reproductive parameters or CM in the first 42 days post-calving. These results suggest that while inherited peripartum adaptation strategies have been developed by the different genetic groups selected in different environments (pasture5NZ v. confinement5NA), such differences have minimal impact on peripartum clinical health.