Recent Submissions

  • A note on the effects of a combination of an enzyme complex and probiotic in the diet on performance of broiler chickens

    Momtazan, R.; Moravej, H.; Zaghari, M.; Taheri, H.R. (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
    The object of this experiment was to investigate the effect of an enzyme complex and a probiotic mixture, offered either singly or in combination, in the diet of broiler chickens (from 1 to 47 days of age) on growth and digestive tract weight and length. A total of 480 1-day old male Ross-308 broilers were allocated to 6 treatments, with 4 replicates of 20 birds each. The treatments were three concentrations of an enzyme complex (0, 250 or 500 mg/kg of the diet) each with and without probiotic supplementation. Inclusion of the enzyme complex linearly improved body weight (BW) and food conversion ratio (FCR) and reduced the relative weight (g/g carcass weight) of duodenum and the length of the jejunum. Probiotic inclusion only improved FCR. However, there was an interaction between the linear effect of enzyme concentration and response to probiotic inclusion for BW, FCR and the relative weight of the duodenum. It is concluded that the combination of the enzyme complex and probiotic can improve the performance more than either supplement used on its own.
  • Prediction of rye dough behaviour and bread quality using response surface methodology

    Banu, I.; Vasilean, I.; Constantin, O.E.; Aprodu, I. (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
    Bread making is a hydro-thermal process; therefore, knowing the behaviour of the main constituents of the flour at different temperatures allows control of the quality of the end-product. Mixing and thermal characteristics were studied using the Mixolab system and response surface methodology was used to investigate the influence of particle size distribution of the flour, pH and the addition of hemicellulase enzyme on the thermo-mechanical behaviour of the whole rye flour and on bread quality. A central composite face-centered design, with two levels of fineness modulus (1.78 and 1.26), two levels of pH (6.5 and 3.8) and three levels of added enzyme (0, 50 and 100 mg/kg of flour), was used. The results indicated that thermo-mechanical variables – water absorption, development time, dough stability, protein weakening, starch gelatinization, starch gelling and cooling setback – as well as bread quality are influenced by the three factors investigated. Significant correlations were found between water absorption and pH, enzyme level, fineness modulus and their interactions. Dough stability was significantly influenced by all the independent variables, as well as by the interaction between pH and fineness modulus. Starch gelling and cooling setback were influenced by the interaction between pH and enzyme level. Concerning bread quality, both porosity and specific volume were affected by enzyme level and pH, as well as by the interaction between fineness modulus and enzyme level.
  • Essential elements and heavy metal concentrations in a small area of the Castlecomer Plateau, Co. Kilkenny, Ireland: Implications for animal performance.

    Canty, M.J.; McCormack, S.; Lane, E.A.; Collins, D.M.; More, Simon J (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
    Many ruminants are solely or mostly dependant for their nutrients, including essential elements, on the forage available to them, either in its natural state or conserved as hay or silage. A soil and herbage survey was carried out in April and September 2007, in a 3.1 km × 3.0 km grid, incorporating 106 and 46 sampling points, respectively, on the Castlecomer Plateau, Co. Kilkenny, Ireland. The aim was to determine the nutrient and heavy metal status of soil and herbage in the sampling area, and to examine the concentrations observed for their potential to impact on animal performance. Low soil pH and high soil lime requirements were identified within the sampling area. The concentrations of Ca, Cu, Se and Zn were low in both soil and herbage. These conditions are similar to those found on other farms in Ireland. Fluoride was detected in 61 of the 97 herbage samples in April 2007, but only four exceeded 40 mg/kg dry matter, the maximum tolerable level for cattle. Mineral imbalances (Ca, Cu, Se and Zn) observed in pastures caused by low soil mineral status, exacerbated by low soil pH, could impair animal performance in the area studied.
  • Analysis and evaluation of the teat-end vacuum condition in different automatic milking systems

    Ströbel, U.; Rose-Meierhöfer, S.; Öz, H.; Entorf, A.C.; Popp, L.; Brunsch, R. (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
    The number of automatic milking systems (AMSs) installed worldwide shows an increasing trend. In comparison to the preliminary models, new versions employ more sophisticated sensor technology than ever before. The originally developed AMSs were characterised by larger vacuum fluctuations and vacuum reductions than conventional milking systems. The objective of this study was to find out whether this situation still holds or if an improvement has occurred. The vacuum behaviour at the teat end of an artificial teat during simulated milking was measured in a study that involved different AMS types (AMS A, B and C). Each system was tested over a range of flow rates (0.8 to 8.0 L/min). The wet-test method was used and teat-end vacuum behaviour was recorded. At a flow rate of 4.8 L/min, the lowest vacuum fluctuation (6.4 kPa in b-phase) was recorded for AMS A, while the lowest vacuum reduction (3.5 kPa in the b-phase) was obtained for AMS B. AMS C yielded higher values for vacuum reduction and vacuum fluctuation. Consequently, it was concluded that AMS A and B, in terms of construction and operational setting (vacuum level), are more appropriate than AMS C. Nevertheless, high values for vacuum reduction or fluctuation have a negative effect on the teat tissue. Hence, one of the future challenges in milk science is to develop a control system that is able to allow fine adjustments to the vacuum curve at the teat end.
  • Intake, growth and feed conversion efficiency of finishing beef cattle offered diets based on triticale, maize or grass silages, or ad libitum concentrates

    O'Kiely, Padraig (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
    The intake, growth and feed conversion efficiency of finishing cattle offered whole-crop triticale silage, harvested at different stubble heights, or maize silage, supplemented with different amounts and forms of crude protein, were compared with those of cattle offered grass silage or concentrate ad libitum. Ninety-eight continental crossbred steers (mean (s.d.) initial live weight 509 (38.6) kg) were allocated among 7 treatments in a randomized complete-block design: triticale silage from a crop harvested to a 14 (TS-L) or 35 (TS-H) cm high stubble, maize silage supplemented with a low (MS-LS) or high (MS-HS) protein concentrate, or with approximately half of the supplementary crude protein replaced by urea (MS-SU), grass silage (GS) or concentrate offered ad libitum (ALC). Each silage was offered ad libitum for 134 days, supplemented with 3 kg concentrate per head daily. Carcass gain did not differ (P>0.05) between animals on treatments TS-L and TS-H, but the carcass gain associated with TS-L was lower (P<0.05) than with GS or MS-HS, and with TS-H compared with MS-HS. Carcass gain was lower (P<0.05) for steers on GS compared to MS-HS, there were no differences (P>0.05) among the values for MS-LS, MS-HS and MS-SU; the carcass gain associated with ALC was the highest (P<0.001). The feed efficiency for carcass gain for the animals on TS-L, TS-H, GS, MS-LS, MS-HS, MS-SU and ALC was 44.1, 48.2, 60.8, 59.3, 68.3, 59.8 and 90.1 (s.e. 4.26) kg/t total DM intake, respectively (P<0.001). It is concluded that the ranking on nutritive value was TS<GS<MS<ALC. Elevating the cutting height of triticale conferred little benefit. Half the soybean meal in the barley-based supplement to maize silage could be replaced by barley plus urea without a negative effect on animal performance.
  • Factors influencing the conservation characteristics of baled and precision-chop grass silages

    McEniry, Joseph; Forristal, P.D.; O'Kiely, Padraig (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
    The composition of baled silage on Irish farms frequently differs from that of comparable precision-chop silage. This paper concerns a field-scale study designed to investigate: (a) the effects of number of layers (2, 4, 6 or 8) of polyethylene stretch film and the duration of storage (7 vs. 18 months) on the conservation characteristics of baled silage, and (b) the conservation characteristics of baled (4 layers of stretch film) and precision-chop silages. All silages were made following three durations of wilting (0, 24 or 48 h). Wilting restricted silage fermentation, with silage pH being highest (P<0.001) and the concentration of fermentation products lowest (P<0.001) for the 48 h wilt treatment. Wrapping bales in only 2 layers of polyethylene stretch film resulted in extensive visible mould growth, but mould growth was practically eliminated by the application of 4 or more layers of film. Silage fermentation characteristics were generally improved by wilting, and by 4 compared to 2 layers of stretch film. Extending the storage duration of baled silage from 7 to 18 months reduced (P<0.001) the concentration of fermentation products and increased in-silo fresh weight losses (P<0.001) and visible mould growth. Whereas 4 layers of conventional stretch film are normally sufficient, 6 layers may be necessary to prevent mould growth when bales of unwilted silage are stored for a second season. Under good farm-management conditions differences observed between baled and precision-chop silages probably result mainly from differences in the concentration of dry matter in herbage at ensiling.
  • Effect of post-weaning management practices on physiological and immunological responses of weaned beef calves

    Lynch, Eilish M; McGee, Mark; Doyle, Sean; Earley, Bernadette (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
    The objectives were: i) to investigate the physiological and immunological responses of previously grazed, abruptly weaned beef calves that were then either housed (H) and offered a diet of grass silage ad libitum plus concentrate or returned to familiar pasture (P) (Phase I), and ii) to examine the effect of subsequent housing (35 days post-weaning) on these responses in P calves compared with the H calves, which were acclimated to housing (Phase II). Rectal temperature was recorded and jugular blood was collected on days 0 (weaning), 2, 7, 14, 21, 28 and 35 (Phase I) and on days 0 (housing of P), 2, 7, 14, and 21 (Phase II). There was a treatment × sampling time interaction (P<0.05) for rectal temperature, fibrinogen concentration, total leukocyte and lymphocyte number, and phytohaemagglutinin-induced interferon-γ production during Phase I, with H calves having higher (P<0.05) rectal temperature and fibrinogen concentrations on day 7, lower total leukocyte and lymphocyte number on days 7 to 35 and days 2 to 28, respectively, and reduced interferon-γ production on day 7 compared with P calves. Neutrophilia (P<0.05) was present in P calves on days 2 and 7 post-weaning. In Phase II, total leukocyte and neutrophil numbers increased (P<0.05), whereas lymphocyte number declined on day 2 relative to values on day 0 of Phase II. In conclusion, deferring housing at the time of weaning resulted in a less marked stress response in beef calves compared with the traditional combined practice of weaning and simultaneous housing, however these changes were minimal suggesting that the overall health and welfare of beef calves was not compromised by abrupt weaning and simultaneous housing.
  • Urine patch distribution under dairy grazing at three stocking rates in Ireland

    Dennis, S.J.; Moir, J.L.; Cameron, K.C.; Di, H.J.; Hennessy, D.; Richards, Karl G. (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
    Nitrate pollution of water is a serious global environmental issue. Grassland agriculture is a major source of diffuse nitrate pollution, with much of this nitrate originating from the urine patches of grazing animals. To study nitrate losses from grassland it is necessary to consider the areas of grassland that are affected by urine separately from the remainder of the pasture. Urine patches can be observed in the field as areas of vigorously growing pasture, however the pasture may continue to respond for several months, making it difficult to determine when the observed patch was actually deposited. A global positioning system was used to record the location of all urine and dung patches in a pasture at every second grazing on an Irish dairy farm during the grazing season. Any patches reappearing were removed from the data, allowing the fresh urine patches to be identified. Dairy cows deposited 0.359 urine patches per grazing hour, a value that may be used to predict the distribution of urine patches under any grazing regime. This equated to 14.1 to 20.7% of the soil surface being wet by urine annually at stocking rates of 2.0 to 2.94 cows per hectare, consistent with previous research. These values may be used in conjunction with values for nitrate loss from urine and non-urine areas to calculate nitrate losses from grazed pasture at a range of stocking rates.
  • Relationship between live weight and body condition score in Irish Holstein-Friesian dairy cows

    Berry, Donagh P.; Buckley, Frank; Dillon, Pat (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
    The objective of this study was to quantify the change in live weight (LWT) per unit change in body condition score (BCS) for Irish Holstein-Friesian dairy cows. Mixed model analyses were performed on 82 948 test-day records of BCS and LWT across 11 075 lactations from 7391 cows, representing 62 commercial and 4 research herds, during the years 1999 and 2000. Factors included in the mixed models were parity, stage of the inter-calving interval and the three-way interaction between herd, year and fortnight of the calendar year at calving. Interactions between the effect of BCS and either parity or stage of the inter-calving interval were included in some models to evaluate the effect of these factors on the relationship between LWT and BCS. A moderate correlation (0.49) existed between BCS and LWT in the complete dataset, but it differed significantly with parity and stage of the inter-calving interval (range 0.36 to 0.59). Analysis of the entire dataset yielded an estimate of 50 kg LWT change per unit change in BCS and this coefficient ranged from 39 kg to 66 kg, depending on parity or the stage of the inter-calving interval. Accurate values of LWT per unit BCS are important input parameters for animal or herd-level biological models designed to evaluate the energy demands of the animal or herd.
  • Comparative performance and economic appraisal of Holstein-Friesian, Jersey and Jersey×Holstein-Friesian cows under seasonal pasture-based management

    Prendiville, R.; Shalloo, Laurence; Pierce, K.M.; Buckley, Frank (Teagasc (Agriculture and Food Development Authority), Ireland, 2011)
    The objective of this study was to provide comparative performance data for Holstein- Friesian (HF), Jersey (J) and Jersey×Holstein-Friesian (F1) cows under a seasonal pasture-based management system and to simulate the effect of cow breed on farm profitability. Data for a total of 329 lactations, from 162 (65 HF, 48 J and 49 F1) cows, were available. Milk yield was highest for HF, intermediate for F1 and lowest for J, while milk fat and protein concentrations were highest for J, intermediate for F1 and lowest for HF. Yield of fat plus protein was highest for F1, intermediate for HF and lowest for J. Mean bodyweight was 523, 387 and 466 kg for HF, J and F1, respectively. Body condition score was greater for the J and F1 compared to HF. Reproductive efficiency was similar for the HF and J but superior for the F1. The Moorepark Dairy Systems Model was used to simulate a 40 ha farm integrating biological data for each breed group. Milk output was highest for systems based on HF cows. Total sales of milk solids and, consequently, milk receipts were higher with J and F1 compared to HF. Total costs were lowest with F1 cows, intermediate with HF and highest with J. Overall farm profitability was highest with F1 cows, intermediate with HF and lowest with J. Sensitivity analysis of milk price, fat to protein price ratio and differences in cost of replacement heifers showed no re-ranking of the breed groups for farm profit.