Recent Submissions

  • A note on the evaluation of the acid-insoluble ash technique as a method for determining apparent diet digestibility in beef cattle.

    McGeough, E.J.; O'Kiely, Padraig; Kenny, David A. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    The objective was to determine if the acid-insoluble ash (AIA) method provided accurate estimates of in vivo apparent digestibility compared with the standard total faecal collection (TFC) method. Twelve steers, mean live weight 328 (s.d. 27.3) kg, were offered one of three diets based on whole-crop wheat (WCW) or a grass silage (GS) diet in a 4 × 4 latin square design. Apparent dietary digestibility was determined simultaneously using AIA and TFC methods. Agreement between the two methods depended on diet type, with acceptable agreement (a difference between the methods of 0.06), observed with the WCW-based diets. However, the strength of the agreement was weakened with the inclusion of GS. Agreement statistics were found to be a useful tool for assessing the relationship between the two methods of measurement.
  • A note on the effect of the composition of barley produced at different locations on performance of growing pigs.

    Ball, M.E.E.; McEvoy, J.D.G.; McCracken, K.J. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    Location of production has been shown to affect the nutritive value of barley for growing pigs, but there is a lack of information regarding the effect of this factor on pig performance. The barley variety “Riviera” was produced at nine different locations in Northern Ireland and formulated into diets (barley, soyabean meal and tallow at 650, 283 and 30 g/kg, respectively) for growing pigs. Diets were offered ad libitum to a total of 72 individually housed pigs from 8 to 11 weeks of age. Average start and end weights were 19 and 34 kg, respectively. Location of production had no significant effect on animal performance although a wide range was observed, which may be important under commercial conditions. Barley specific weight was not strongly correlated (r2 < 0.10) with any performance trait indicating that an alternative means of predicting the nutritive value of barely for pigs is required. A significant positive relationship was observed between barley β-glucan concentration and feed conversion ratio (r2 = 0.65).
  • A note on the effect of post-mortem maturation on colour of bovine Longissimus dorsi muscle

    Dunne, Peter G.; Monahan, F.J.; Moloney, Aidan P (Teagasc, Oak Park, Carlow, Ireland, 2010)
    Fifteen heifers were housed and fed a concentrate diet while 54 counterparts grazed at pasture for 90 days at which stage six heifers from each group were slaughtered. The remaining animals in the pasture group were then housed and offered either: concentrate only; concentrate plus grass silage with silage accounting for either 20% or 50% of the total dry matter offered; or zero-grazed grass plus concentrate with grass accounting for 83% of the dry matter offered. Heifers (3/diet) were slaughtered 28, 56, 91 and 120 days thereafter. Colour characteristics of M. longissimus dorsi (LD) were measured at 48 h post mortem. The LD was then vacuum-packaged and stored at between 0 and 4 °C in darkness for 12 days, when colour characteristics were again measured. Maturation of LD resulted in meat that had higher redness values (‘a’ value; P<0.001) and a more intense red colour (higher ‘C’ value; P<0.001) at 14 days post mortem than at 2 days, regardless of diet/duration of feeding. Maturation also resulted in a brighter colour (higher ‘L’ value; P<0.001) but this difference was greatest when cattle were slaughtered the day-56 time point.
  • A note on the effect of calcium alginate coating on quality of refrigerated strawberries.

    Moayednia, N.; Ehsani, M.R.; Emamdjomeh, Z.; Mazaheri Asadi, M.; Mizani, M.; Mazaheri, A.F. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    An alginate-based edible coating was investigated for the preservation of the quality of strawberries during cold storage (5 °C). Strawberries were immersed, successively, in sodium alginate and calcium chloride solutions to generate a surface coating of calcium alginate. The quality of coated and non-coated strawberries was evaluated by weight loss, visible decay, titratable acidity, total soluble solids and reducing sugar concentration over a 14-day storage period. Results showed that coating with calcium alginate had no significant effects on weight loss or physicochemical parameters when compared to control fruit, but it did result in the postponement of visible decay during refrigerated storage.
  • A note on the conservation characteristics of baled grass silages ensiled with different additives.

    Keles, G.; O'Kiely, Padraig; Forristal, P.D. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    The effects of contrasting conventional silage additives on chemical composition, aerobic stability and deterioration, and mould development in baled silage were investigated. Herbage from a grassland sward was wilted for 24 h and treated with acid (formic or sulphuric), sugar (molasses), bacterial (Lactobacillus plantarum, L. plantarum + Serratia rubidaea + Bacillus subtilis, or L. buchneri) or sugar + bacterial (molasses + L. plantarum) additives prior to baling and wrapping. Silage made without an additive preserved well and had a low incidence of mould growth, and the effects of additives were minor or absent. It is concluded that little practical benefit was realised when conventional additives were applied to wilted, leafy, easy-to-ensile grass prior to baling and ensilage.
  • The effects of leaf litter treatments, post-harvest urea and omission of early season fungicide sprays on the overwintering of apple scab on Bramley’s Seedling grown in a maritime environment.

    Mac an tSaoir, S.; Cooke, L.R.; McCracken, A.R. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    The theory that orchards with zero or low levels of apple scab post harvest do not need scab protection at the start of the next growing season was evaluated under Irish conditions. In addition, a range of post-harvest orchard sanitation practices (application of urea to rot overwintering leaves, mowing the orchard or total leaf removal in February) were also evaluated. Due to the high summer rainfall in Ireland (compared to all other European apple growing areas) and the severe susceptibility of the apple cultivar Bramley’s Seedling to scab (Venturia inaequalis), neither clean orchards in the autumn nor sanitation practices were sufficient to eliminate the requirement for full fungicide protection programmes at the start of the following growing season. Post harvest applications of urea proved difficult due to late harvesting of pollinator fruit for the juice market and wet weather. Total removal of leaf litter from plots prior to the commencement of growth did not significantly reduce disease incidence. Regardless of orchard cleanliness in autumn, missing the first fungicide application in the spring always reduced yield.
  • Effects of forage supplements on milk production and chemical properties, in vivo digestibility, rumen fermentation and N excretion in dairy cows offered red clover silage and corn silage or dry ground corn

    Salcedo, G.; Martinez-Suller, L.; Arriaga, H.; Merino, P. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    This study concerned the effects of partial substitution of clover silage with high starch forages on milk production and chemical composition, in vivo digestibility, rumen fermentation pattern and nitrogen excretion of dairy cows. Sixteen dairy cows were separated into two groups and were assigned to treatments in a two-period crossover design. Two forage supplements were used: corn silage (CS) and dry ground corn (DG). All animals received 4.5 kg of concentrate dry matter per day. Results showed no significant difference between the forage supplements for milk production, while significant differences (P<0.01) were observed for milk fat, milk protein and nitrogen utilisation efficiency (42 v. 4.0 g/kg, 3.5 v. 3.3 g/kg and 222 v. 188 g/kg, respectively, for DG and CS). Faecal N excretion did not differ between forage supplements, but urinary N excretion was higher for CS (P<0.05). No significant differences were observed between treatments for rumen fluid pH or for rumen fluid concentrations of ammonium nitrogen or of acetic, propionic or butyric acids. Dry matter intake and the in vivo digestibility of dry matter, organic matter, acid detergent fibre and neutral detergent fibre were all higher for CS compared with DG.
  • Effects of finishing strategy on performance of Belgian Blue × Friesian and Limousin × Friesian steers.

    Keane, Michael G. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    Belgian Blue and Limousin bulls are used for cross-breeding with Holstein Friesian dairy cows in Ireland. In beef winter-finishing enterprises, a preliminary feeding period sometimes precedes the finishing period. The optimum feeding level for this period has not been established. The objective of this study was to compare lifetime performance of Belgian Blue × Holstein Friesian (BB) and Limousin × Holstein Friesian (LM) steers and to determine the effects of three finishing strategies on performance and carcass traits. Fortyeight spring-born male calves (24 BB and 24 LM), the progeny of Limousin and Belgian Blue bulls out of Holstein Friesian cows, were reared together to slaughter. At about 19 months of age they were assigned to one of three finishing strategies involving grass silage ad libitum plus 0, 3 or 6 kg concentrates per head daily for 112 days (preliminary period) followed by concentrates ad libitum to slaughter at 610 kg live weight. Slaughter weight and carcass weight did not differ between the breed types but BB had a higher kill-out proportion, better carcass conformation and lower carcass fatness. Live-weight gains during the preliminary period were 431, 914 and 1134 g/day (s.e. 31.8; P < 0.001) for the 0, 3 and 6 kg/day concentrate levels, respectively. Overall gains for the combined preliminary and finishing periods for the treatments in the same order were 945, 1101 and 1081 g/day (s.e. 36.1; P < 0.01). There were few differences between the finishing treatments in slaughter weight, carcass weight or carcass traits. It is concluded that general productivity is similar for BB and LM but BB have superior carcass traits. Where a preliminary feeding period precedes a finishing period on ad libitum concentrates, animals fed a low level of supplementary concentrates require less feed energy to reach a fixed slaughter weight than those fed none or a higher level of supplementary concentrates.
  • The effect of supplementary grass silage and standard concentrate on milk fat fatty acid composition and iodine value when cows are fed a whole rapeseed-based concentrate at pasture

    Magowan, E.; Fearon, A.M.; Patterson, D.C. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    The use of grass silage and concentrates to supplement fresh grass intake is commonly practised in dairy systems. However, the effects of such supplementation within a dietary regime designed to produce a spreadable butter are unknown. Sixteen Holstein Friesian cows were used in an incomplete changeover design to investigate the effect on milk fat of supplementation with grass silage (GS) or standard concentrate (SC) when offering a concentrate based on whole rapeseed at pasture (RC+G). A control diet of fresh grass and standard concentrate (SC+G) was also included. Diet had no effect (P > 0.05) on milk yield or on the lactose concentration of milk. The iodine value (IV; grams of iodine per 100 g milk fat) of milk fat with the RC+G diet was greater (43.9, P < 0.05) than with the SC+G diet (39.9). The iodine value of milk fat was reduced (P < 0.05) when RC+G+GS was offered (41.5 g/100g), but not when RC+G+SC was offered (43.1 g/100g), compared with when RC+G was offered. The proportion of unsaturated fatty acids in milk fat was higher (P < 0.05) when the RC+G diet was offered compared with either RC+G+GS or RC+G+SC. If supplementary feedstuffs are to be used in combination with a wholerapeseed- based concentrate and pasture, then inclusion of standard concentrate would be preferred over grass silage because the negative impact on the iodine value of milk fat was less. However, further research is required to investigate the effect on IV of milk fat when a standard concentrate supplement is offered at levels that increase milk yield.
  • Effect of phosphorus level and phytase inclusion on the performance, bone mineral concentration, apparent nutrient digestibility, and on mineral and nitrogen utilisation in finisher pigs.

    Varley, T.F.; Callan, J.J.; O'Doherty, J.V. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    Two experiments were conducted to investigate the interaction between dietary P concentration and phytase (PHY) inclusion in the diet of finisher pigs. In Experiment 1, the growth performance and bone analysis experiment, pigs (6 replicate groups of 14 pigs each per treatment; initial body weight (BW) = 45.2 kg) were allocated to one of six dietary treatments (for 74 days) in a 3 × 2 factorial arrangement: T1 – available P in the diet = 1.5 g/kg; T2 = T1 with 500 units of phytase (FTU)/kg; T3 – available P = 2.0 g/kg; T4 = T3 with 500 FTU/kg; T5 – available P = 2.5 g/kg; T6 = T5 with 500 FTU/kg. Experiment 2 consisted of a digestibility and a P, Ca and N balance study, and pigs (6 per treatment; initial BW = 67.3 kg) were offered identical diets to those offered in Experiment 1. There was an interaction between dietary P level and PHY inclusion for average daily gain (ADG) and carcass weight (CW; P < 0.05) in Experiment 1. Pigs offered the low P diet supplemented with PHY had a higher ADG and CW than pigs offered the non-PHY, low P diet. However, there was no effect (P > 0.05) of PHY inclusion on ADG or CW with the medium or high P diets. Higher concentrations of ash, P and Ca in bone were noted in pigs offered the medium and high P diets (P < 0.001) and PHY (P < 0.01) diets when compared to pigs offered the low P without PHY. Pigs offered diets supplemented with PHY had lower faecal P output (P < 0.01) and a higher P digestibility (P < 0.001) and P retention (P < 0.05) than pigs offered diets without added PHY. In conclusion, supplementation of a low-P finisher diet with PHY resulted in pigs that had a similar carcass weight, but weaker bones than pigs offered a medium or high P diet.
  • Comparison of pasture and concentrate finishing of Holstein Friesian, Aberdeen Angus × Holstein Friesian and Belgian Blue × Holstein Friesian steers

    Keane, Michael G.; Moloney, Aidan P (Teagasc, Oak Park, Carlow, Ireland, 2010)
    Crossbreeding Holstein Friesian dairy cows with both early and late maturing beef breed bulls is common in Ireland. This study concerned the comparison of spring-born Holstein Friesian (HF), Aberdeen Angus × Holstein Friesian (AA) and Belgian Blue × Holstein Friesian (BB) steers slaughtered directly off pasture in the autumn or following a period of concentrate finishing indoors. Male calves (18 per breed type) were reared together until August of their second year when they were assigned to a 3 (breed type) × 3 (finishing strategy) factorial experiment. The three finishing strategies were (i) pasture only for 94 days to slaughter (PE), (ii) concentrate ad libitum indoors for 94 days to slaughter (CE), and (iii) pasture only for 94 days followed by concentrate ad libitum indoors for 98 days to slaughter (PC). For HF, AA, and BB, mean carcass weight, carcass conformation score and carcass fat score values were 275, 284 and 301 (s.e. 5.1) kg, 1.75, 2.42 and 2.89 (s.e. 0.11), and 2.48, 2.89 and 2.17 (s.e. 0.11), respectively. Pasture alone supported live-weight and carcass-weight gains of approximately 800 g/day and 400 g/day, respectively. Live-weight and carcass-weight gains on concentrate ad libitum were approximately 1400 and 870 g/day, respectively. For PE, CE and PC, mean carcass weight, carcass conformation score and carcass fat score values were 244, 287 and 329 (s.e. 5.1) kg, 1.81, 2.56 and 2.69 (s.e. 0.11), and 1.83, 2.71 and 3.01 (s.e. 0.11), respectively. It is concluded that none of the breed types reached an acceptable carcass weight on PE and only HF had acceptable carcass finish. All breed types were acceptably finished on both concentrate finishing strategies.
  • A comparison of finishing strategies to fixed slaughter weights for Holstein Friesian and Belgian Blue × Holstein Friesian steers

    Keane, Michael G. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    Cattle finishing strategies may involve feeding a high energy diet throughout or following a period of moderate growth. The objective of this study was to compare Holstein Friesian (HF) and Belgian Blue × Holstein Friesian (BB) steers (24 per breed type, initial live weight 434 and 431 kg for HF and BB, respectively) finished to 560 kg or 620 kg target slaughter weight, on either a concentrate diet ad libitum from the start of the finishing period (C), or on a concentrate diet ad libitum following an 84-day period on grass silage (SC). Slaughter weights were similar for HF and BB, but kill-out proportion, carcass weight and carcass conformation class were superior (P < 0.001), and carcass fat score was inferior (P < 0.001), for BB. Total concentrate, dry matter and net energy intakes were higher (P < 0.001) for HF, and efficiency of utilization of net energy for carcass-weight gain was lower (P < 0.01). Mean daily live-weight gain was higher for C than SC (P < 0.001) and for slaughter at 560 kg than at 620 kg (P < 0.05). Killout proportion was higher for C than SC (P < 0.05) and for 620 kg compared to 560 kg slaughter weight (P < 0.001). Measures of fatness were unaffected by feeding treatment but all were higher (P < 0.01) for the 620 kg slaughter weight. Net energy required per unit carcass-weight gain was higher for C than SC (P < 0.001) and for 620 kg than for 560 kg slaughter weight (P < 0.001). When slaughtered at 620 kg live weight there was no difference between the feeding treatments in net energy required per unit carcass-weight gain. While both breed types had similar live-weight gain BB had 9% greater (P < 0.01) carcass-weight gain and were 14% more efficient (P < 0.01) in converting feed energy to carcass weight. Neither breed type had commercially acceptable carcasses at 560 kg slaughter weight when finished on SC.
  • Associations between the K232A polymorphism in the diacylglycerol-O-transferase 1 (DGAT1) gene and performance in Irish Holstein-Friesian dairy cattle

    Berry, Donagh P.; Howard, Dawn J.; O'Boyle, P.; Waters, Sinead M.; Kearney, J.F.; McCabe, M. (Teagasc, Oak Park, Carlow, Ireland, 2010)
    Selection based on genetic polymorphisms requires accurate quantification of the effect or association of the polymorphisms with all traits of economic importance. The objective of this study was to estimate, using progeny performance data on 848 Holstein-Friesian bulls, the association between a non-conservative alanine to lysine amino acid change (K232A) in exon 8 of the diacylglycerol-O-transferase 1 (DGAT1) gene and milk production and functionality in the Irish Holstein-Friesian population. The DGAT1 gene encodes the diacylglycerol-O-transferase microsomal enzyme necessary to catalyze the final step in triglyceride synthesis. Weighted mixed model methodology, accounting for the additive genetic relationships among animals, was used to evaluate the association between performance and the K232A polymorphism. The minor allele frequency (K allele) was 0.32. One copy of the K allele was associated (P < 0.001) with 77 kg less milk yield, 4.22 kg more fat yield, 0.99 kg less protein yield, and 1.30 and 0.28 g/kg greater milk fat and protein concentration, respectively; all traits were based on predicted 305-day production across the first five lactations. The K232A polymorphism explained 4.8%, 10.3% and 1.0% of the genetic variance in milk yield, fat yield and protein yield, respectively. There was no association between the K232A polymorphism and fertility, functional survival, calving performance, carcass traits, or any conformation trait with the exception of rump width and carcass conformation. Using the current economic values for the milk production traits in the Irish total merit index, one copy of the K allele is worth €5.43 in expected profitability of progeny. Results from this study will be useful in quantifying the cost-benefit of including the K232A polymorphism in the Irish national breeding programme.
  • The composition of dirty water on dairy farms in Ireland

    Martinez-Suller, L.; Provolo, G.; Carton, Owen T.; Brennan, D.; Kirwan, Laura; Richards, Karl G. (Teagasc, 2010)
    Considerable quantities of dirty water, composed of milking parlour wash-water, milk spillages, runoff from cattle yard areas and, possibly, effluent from silage and manure, are produced on dairy farms. In Ireland, dirty water from dairy farm facilities is normally managed by spreading on, or irrigation to, land. It has considerable potential to cause water pollution due to its high pH, 5-day biochemical oxygen demand and its N and P concentrations. The objective of the present study was to contribute to better management of dirty water on dairy farms by providing estimates of its composition using rapid methods that can be easily used on farms. During the experiment, 34 samples were collected from the facilities on the dairy farm at Teagasc, Johnstown Castle (Wexford), between 27 January and 1 May, 2006. Dry matter and specific gravity provided the best indicator of biochemical oxygen demand, total nitrogen and phosphorous, and micro and macro nutrients. The nutrient concentration of dirty water can be determined rapidly using either dry matter concentration or specific gravity, enabling farmers to include this information in the nutrient management plan for their farm.
  • A note on the estimation of nutrient value of cattle slurry using easily determined physical and chemical parameters

    Martinez-Suller, L.; Provolo, G.; Brennan, D.; Howlin, T.; Carton, Owen T.; Lalor, Stanley T. J.; Richards, Karl G. (Teagasc, 2010)
    The composition of cattle slurries can vary greatly due to factors such as farm management, meteorology, animal diet and housing system. Thus, when spread on land, the precise fertiliser value is usually unknown. In this study, 41 samples of cattle slurry from farms in Co. Wexford, were analysed for electrical conductivity (EC), pH, and for concentrations of dry matter (DM), total Kjeldahl N, total P and total K. Correlations between physico-chemical properties (pH, EC, DM) and nutrient concentration showed that DM and EC could be used to estimate nutrient concentration. Generally, DM was the best estimator of N (R2 0.75) and P (R2 0.82), while EC was the best estimator of K (R2 0.73). EC was also highly correlated with N concentration (R2 0.67). The proportion of variation accounted did not substantially increase when multiple regression was used.
  • Predicting soil moisture conditions for arable free draining soils in Ireland under spring cereal crop production

    Premrov, Alina; Schulte, Rogier P.; Coxon, Catherine E.; Hackett, Richard; Richards, Karl G. (Teagasc, 2010)
    Temporal prediction of soil moisture and evapotranspiration has a crucial role in agricultural and environmental management. A lack of Irish models for predicting evapotranspiration and soil moisture conditions for arable soils still represents a knowledge gap in this particular area of Irish agro-climatic modelling. The soil moisture deficit (SMD) crop model presented in this paper is based on the SMD hybrid model for Irish grassland (Schulte et al., 2005). Crop and site specific components (free-draining soil) have been integrated in the new model, which was calibrated and tested using soil tension measurements from two experimental sites located on a well-drained soil under spring barley cultivation in south-eastern Ireland. Calibration of the model gave an R2 of 0.71 for the relationship between predicted SMD and measured soil tension, while model testing yielded R2 values of 0.67 and 0.65 (two sites). The crop model presented here is designed to predict soil moisture conditions and effective drainage (i.e., leaching events). The model provided reasonable predictions of soil moisture conditions and effective drainage within its boundaries, i.e., free-draining land used for spring cereal production under Irish conditions. In general, the model is simple and practical due to the small number of required input parameters, and due to model outputs that have good practical applicability, such as for computing the cumulative amount of watersoluble nutrients leached from arable land under spring cereals in free-draining soils.