• Welfare and health of dairy cattle on out-wintering pads or in cubicle housing with or without cushioned flooring.

      Boyle, Laura; Mee, John F; O'Donovan, Michael; Kiernan, Paul (Teagasc, 2-10-01)
      The first study described in this report involved housing 66 spring calving heifers in one of three systems during the winter, namely, (i) a conventional cubicle house, (ii) a cubicle house with cushioned flooring covering the slats (slat mats) in the passageway and (iii) on a wood-chip out-wintering pad. Behaviour, health and performance indicators were measured on all animals while pregnant from housing in November 2003 until calving in January 2004. Additionally, data were collected on the first 15 animals to calve in each treatment for the first four weeks of lactation in the spring. The slat mats resulted in some improvements to hoof health compared to the conventional cubicle house. Furthermore, it increased feeding times although this had no effect on feed intake or performance. The results also indicated that heifers have a preference for standing on cushioned flooring rather than on concrete during late pregnancy. Both groups indoors differed greatly from the outdoor heifers in several respects. The outdoor animals had healthier feet and were less affected by injuries to the limbs. They also had a more diverse behaviour repertoire and slipped and tripped less. However, their welfare was adversely affected by inclement weather conditions with indications of immunosuppression combined with a reduction in average daily gain being recorded. Furthermore, they were dirtier and spent less time lying down. None of these factors influenced milk yield, quality or composition in early lactation. Welfare problems associated with the pad were weather and management dependent and hence could be addressed by more frequent cleaning of the pad and/or an increase in space allowance combined with the provision of shelter. Hence, the potential for good welfare in dairy heifers was higher on the pad than indoors in a cubicle system even when slat mats were provided. In the second study, 62 autumn calving pluriparous dairy cows were housed in September 2004 in a cubicle system with either solid concrete floors or solid concrete floors covered by a rubber mat and cleaned by an automatic scrapper. Behaviour, locomotion and foot lesion scores were recorded from at least 3 weeks prior to calving until at least 16 weeks post-partum. Furthermore, in-depth measures of oestrous behaviour and reproductive performance were recorded. The cushioned flooring had no effect on sole or white line lesion scores or on dermatitis scores. However, it reduced the rate of wear of the heels in early lactation. Cows on cushioned flooring spent more time standing, but not feeding, at the feed face while cows on concrete stood in the cubicles instead. It appears that where cows have access to spacious, well-designed cubicles they can use them for standing to get relief for their feet from the concrete. Similar to the previous study this also indicates that cows prefer to stand on cushioned flooring than on bare concrete and emphasises the importance of at least providing cows with mats or mattresses in their cubicles. There were no effects of the cushioned flooring on oestrous behaviour or reproductive performance, which was poor in both treatments. It is suggested that the reasons for this were that the cushioned flooring did not provide sufficient traction for the cows and so they were as reluctant as the cows on concrete to perform mounting behaviour.
    • Variation in the quality of meat from Irish steers at the time of slaughter.

      Moloney, Aidan P; Mullen, Anne Maria; Maher, S.C.; Buckley, D.J.; Kerry, J.P. (Teagasc, 01/01/2004)
      There is no information on the variation in quality, in particular tenderness, that exists in Irish Beef nor is there information on the variation that would remain if optimum practices were imposed at all stages of the beef production chain. Evaluation of the success of measures to improve beef consistency requires information on existing variation and the minimum variation achievable.The objectives of this project were (i) to establish the variation that exists in the quality of meat from Irish cattle, (ii) to quantify the minimum variation in meat quality that can be achieved in a practical beef production system, (iii) to determine the effects and mechanisms of additional sources of variation. The conclusions from this project are: • The M. longissimus dorsi (loin) was found to be more variable than the M. semimembranosus (topside) for most quality attributes examined (tenderness, sarcomere length and pH). The scale of variation within the loin was similar to that reported by the other research groups within the EU and US. Heifers were more variable than steers for most attributes, while there was no consistent classification effect on the variability of meat quality attributes. • Tenderness was equally variable in meat from genetically similar steers, managed similarly, compared to commercial steers randomly selected from a factory lairage but matched for weight and grade.This was likely a result of both groups being crossbred beef cattle of similar age, fat score, carcass weight and managed identically post-mortem. However, variation in tenderness of both groups was less than that observed in a survey of commercial throughput (experiment 1). This decrease is attributed to better pre-and-post-slaughter handling practices. • The data suggest that selection of sires (within a breed) with better than average conformation has no deleterious effect on the eating quality of beef of their progeny.A more comprehensive comparison of sires within a breed and between breeds is required to confirm the generality of this conclusion. • In a comparison of genotypes, gender and slaughter weights, there was no evidence that variation around the mean value for tenderness differed between breeds or liveweights after 14 days ageing. Bulls were more variable than steers for some quality traits but the variation in tenderness was similar for bulls and steers after 14 days ageing. • While optimising the management of animals during the pre and post-slaughter period reduced variation in tenderness, some residual variation remained. A large percentage of the residual variation in tenderness (Warner Bratzler shear force) after 2 and 7 days post-mortem was explained by proteolysis (breakdown of myofibrillar proteins).Variation in tenderness (Warner Bratzler shear force) after 2 days post-mortem was largely explained by phosphates (energy) and proteolysis, while sensory tenderness was largely explained by phosphates and glycolytic potential. • Further work is required to reduce residual variation in Irish beef and to determine the causes of this variation.
    • 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.
    • An examination of the molecular mechanisms controlling the tissue accumulation of conjugated linoleic acid (CLA) in cattle

      Waters, Sinead M.; Hynes, A.C.; Killeen, Aideen P.; Moloney, Aidan P; Kenny, David A. (Teagasc, 01/12/2008)
      Long chain n-3 polyunsaturated fatty acids (n-3 PUFA) and conjugated linoleic acid (CLA) have demonstrable and potential human health benefits in terms of preventing cancer, diabetes, chronic inflammation, obesity and coronary heart disease. Supplementation of cattle diets with a blend of oils rich in n-3 PUFA and linoleic acid have a synergistic effect on the accumulation of ruminal and tissue concentrations of trans vaccenic acid (TVA), the main substrate for ?-9 desaturase which is responsible for de novo tissue synthesis of the cis 9, trans 11 isomer of CLA. This dietary strategy translates into increases in milk concentrations of CLA in dairy cows; however, concentrations in the muscle of beef animals have not always been increased. There is an apparent paradox in that n-3 PUFA supplementation enhances ruminal synthesis of trans-vaccenic acid (TVA), but then inhibits its conversion to CLA possibly through altering the activity of ?-9 desaturase. Recently, the promoter regions of the bovine ?- 9 desaturase gene has been isolated and analysed and has been shown to contain a conserved PUFA response region.
    • Replacement strategies to maximise profiltability in dairying.

      Crosse, Seamus; Haran, P.; Killen, L. (Teagasc, 1998-01-01)
      The overall objective of this project was to develop a dynamic model which would determine the optimum replacement rates for dairy herds under an Irish system of production. A model was designed and applied to the Irish dairy replacement problem, which included in the decision making process production, fertility, calving interval, seasonality, month of calving and various economic factors. The output from the Hierarchic model is a series of rankings. The dynamic programming approach can enable one to inform a farmer which cows in the herd should be replaced, on the basis that a replacement heifer( and its future successors) are expected to be more profitable than the current cow. The optimum replacement rate was 17.8% from this analysis.
    • The development of feeding and management strategies for milk production systems with very contrasting milk supply patterns.

      Ryan, G.; Crosse, Seamus; Fitzgerald, S. (Teagasc, 1998-01-01)
      In Experiment 1, three systems of milk production with contrasting calving patterns, namely 100% autumn (A); 100% spring (S) and 50% autumn: 50% spring (AS), were compared over a two year period. The average milk yield was 6,532, 6,358 and 6,142 kg/cow for systems A, AS and S respectively. The difference in yield was not statistically significant. Fat yield, fat content and protein yield for system S was significantly lower than those with the other two systems. The autumn-calving cows (A) had reduced reproductive performance. Experiment 2 compared grazed grass with grass silage as a forage source for autumn-calving cows in early lactation; it showed that the cows on grazed grass had significantly higher milk protein yield and milk protein content. The cows on the grass silage had significantly lower dry matter intake and a significantly higher bodyweight loss post-calving. The aim of this project was to develop low-cost systems of milk production which lead to an improved milk supply pattern of quality milk for the food industry. In particular, the objective was to research the role which grazed grass can contribute to the feed requirements of cows calving at different times during the year.
    • Animal Welfare Guidelines for Beef Producing Farms

      Fallon, Richard J.; Earley, Bernadette; Finnerty, Martina (Teagasc, 1998-10-01)
      The scientific consideration of farm animal welfare is important, due to ethical obligation to maximise health and well-being and eliminate suffering in animals that are under human stewardship, fulfil the requirements and demands of the general community and improve the efficiency of animal agriculture by optimising animal health and productivity. The welfare guidelines are intended to enable farmers to adopt the highest standards of animal health and welfare.
    • Reducing the seasonality of prime lamb production

      Grennan, E.J. (Teagasc, 1998-10-01)
      Lambing part of the national lowland flock in April to late May has potential to reduce the seasonality of supply and extend the season for prime young lamb. This would, potentially, enhance ability to maintain and increase market share for Irish lamb. A farmlet system was operated over two years, with some 50 ewes on 4 ha of pasture. The objectives were: to assess the overall performance of a flock lambing in mid to late April : to monitor lamb growth rate and drafting patterns for lambs; to determine the changes in feed demand over the season; to identify any saving in feed costs, and any difficulties that may arise with late lambing. The feed demand over the grazing season differs from normal March lambing. A grass surplus tends to occur in April/May and a deficit in November/December, and this imbalance between supply and demand increases if lambing is in late May. The balance between feed demand and supply may be more easily achieved where sheep are combined with cattle or tillage. Results show that a late-lambing flock can be managed successfully on an all-grass farm. If lambing takes place from mid-April to late May, some lambs will finish off pasture in September/October. Remainder can be finished indoor on silage with concentrate supplementation for sale in October to February. Lambing from mid-April onwards allows ewes to be at pasture for 4 to 6 weeks pre-lambing and concentrate feeding to ewes pre or post lambing should not be necessary. However this saving on concentrate input is offset by the need for concentrates to finish lambs. Lamb growth rate on pasture to weaning will be somewhat lower than with March lambing, due to deterioration in pasture digestibility in mid-season. A high standard of grassland management is critical to maintain pastures leafy, in order to achieve high lamb growth rate pre and post weaning. Profitability will depend on supplying niche markets with younger lambs at premium prices.
    • A comparison of Charolais and beef X Friesian suckler cows.

      Drennan, Michael J.; Fallon, Richard J. (Teagasc, 1998-10-01)
      The studies carried out included comparisons of Charolais and Beef x Friesian suckler cows in terms of voluntary silage intake, colostrum yield and immunoglobulin level, calf immunoglobulin level and cow milk yield in addition to animal production experiments. In all experiments the Charolais animals used were a minimum of 7/8 Charolais and were the result of an upgrading programme at Grange commencing with Charolais x Friesians. In the production experiments, only Hereford x Friesian cows (and their progeny) were compared with the Charolais while in all other experiments the Beef x Friesians included both Hereford x Friesians and Limousin x Friesians.
    • Efficient beef production from grazed pasture.

      O'Riordan, Edward G.; O'Kiely, Padraig; Keane, M.G. (Teagasc, 1998-11-01)
      Documented data comparing both cutting and grazing grass growth rates in Ireland are minimal. Most protocols for measuring grass growth involve a cutting regime of either 3 or 4-week cycles. The effect of the grazing animal is absent in most situations. However, herbage production can readily be affected by the rate of fertiliser nitrogen used and the frequency of grazing/cutting management 6 practices employed. The first two experiments reported here were undertaken to assess grass growth under grazing and cutting regimes and to determine the extent of differences which may arise from different harvesting procotols. The third experiment investigated the effect of nitrogen application rate and regrowth interval on annual herbage production. Early grazing: The experiments reported here were conducted to examine the effects of early turnout to grass on beef cattle production and on sward productivity. Autumn pasture production: The present series of experiments investigated the effects of autumn closing dates on herbage yield and quality as well as their effects on sward productivity. The effects of short and long grazing rest intervals were evaluated in the context of autumn grass growth and their effects on subsequent spring growth.
    • Production of red veal for the EU market.

      Fallon, Richard J.; Drennan, Michael J. (Teagasc, 1998-11-01)
      A summary of four experiments which used Holstein/Friesian bulls and a fifth which used continental cross bulls to determine the effect of feeding ad libitum concentrates on animal prefomance. • The Barley soyabean meal ration provided consistent liveweight gain (1.25 kg/day) and similar cold carcass weight (237 kg) in all four experiments using Holstein and Friesian Bulls. • The Low energy treatment group (Experiment 1) had a liveweight gain of 1.14 kg/day and a cold carcass of 220 kg, i.e. 21 kg lower than that achieved on the High energy treatment group which had a liveweight gain of 1.26 kg/day and a cold carcass of 241 kg. • Providing animals with a summer period outdoors at pasture compared with a continuous period indoors, in general had the effect of improving daily liveweight gain and feed conversion efficiency when animals were offered ad libitum concentrate diet. The effect was greatest when autumn-born calves spent the final 180 days prior to slaughter at pasture. • Restricting the concentrate allowance at pasture brought about a 1.5 unit improvement in FCR carcass, however, at a similar slaughter age this treatment group produced carcasses that were 22 and 21 kg lighter than the control in two respective experiments. • The current economic climate for beef production does not permit the production of red veal in Ireland. However, when markets develop in the Mediterranean countries there will be opportunities to produce red veal carcasses for those markets using male bulls from the Holstein/Friesian herds. • Weaned continental cross suckler bulls slaughtered off an ad libitum concentrate diet at 550 kg liveweight had a feed conversion efficiency of 8.2 kg concentrate DM per kg carcass produced. The corresponding value at 650 kg slaughter, liveweight was 9.5 kg.
    • Maize silage for milk production - Part 1: Effect of the quality of maize silage on milk

      Fitzgerald, J.J.; Murphy, J.J.; O'Mara, Frank P.; Culleton, Noel (Teagasc, 1998-11-01)
      Ensiled forage maize is an alternative or complementary forage to grass silage and is the main source of forage for ruminant livestock in many European countries. The growing of maize for silage was tried unsuccessfully in Ireland in the 1970’s, was resumed in the late 1980’s and is now well established in suitable areas in the south and east of Ireland. However, variation in growing conditions and summer radiation can result in considerable variation in the yield, maturity and feeding value of the crop from year to year and between regions or locations within years. A series of experiments were conducted at Moorepark and at Johnstown Castle Research Centre to evaluate the role of maize silage in the diet of lactating dairy cows, the effect of variation in the quality (starch content and digestibility) of maize silage, the proportion of maize silage in the forage and the effect of harvesting date of immature maize silage on feed intake, milk production and milk composition compared with an all grass silage based diet. Grass silages of moderate or high digestibility were used. These studies were carried out with cows in early or mid lactation or at both stages of lactation. The forages were supplemented with concentrates at low to moderate levels of feeding (4-7 kg/cow/day). The concentrates generally contained a high level of crude protein (220- 250 g CP/kg fresh weight) to balance the low level of crude protein in maize silage. The experiments were conducted over periods of 7-9 weeks.
    • Maize silage for milk production - Part 2: Effect of concentrate quality and quantity fed withmaize silage based forages on milk production

      Fitzgerald, J.J.; Murphy, J.J.; Culleton, N. (Teagasc, 1998-11-01)
      In some of the studies outlined in Part 1 of this report, mixed forages containing grass silage and a high proportion (60%) of maize silages varying in maturity and starch content were supplemented with concentrates at different levels to compare the response in milk production with a maize silage based forage and with good quality grass silage as the sole forage. The most suitable type of energy ingredient in the concentrate, i.e. high starch or low starch, high fibre ingredients, as supplements to maize silage based forages or grass silage was investigated. A range of levels of crude protein in the concentrate were examined in one study to determine the optimum level of crude protein in the supplement for maize silage based forages compared with grass silage.
    • Effect of grazing management on the maintenance of white clover

      Nolan, T.; Grennan, E.J. (Teagasc, 1998-11-01)
      The objectives of the project were to compare different cultivar types and methods to establish and maintain them in reseeded and permanent pastures as a basis for efficient low cost sheep production. In Ireland only 3% of pastures are reseeded annually and permanent pastures rarely contain more than 5% white clover. Improved clover content offers benefits of higher lamb growth rate and reduced fertiliser N use. Comparisons under cutting conditions provided no basis for replacement of Grasslands Huia by the new cultivar Aberherald. Grasslands Huia established successfully following direct reseeding and rotational grazing by sheep. It established more quickly than Kentish and gave higher yield only in the first year. A mixture of small and medium size white clovers should be sown for sheep grazing. Increasing seeding rate from 2 to 4 kg per ha increased pasture clover content only in the first year. Grasslands Huia persisted quite well for up to 5 years under rotational sheep grazing. It also survived under continuous grazing but leaf size was reduced. Rotational grazing management with sheep increased the clover content of permanent pasture from under 2% to 4% over 2 years. Highest clover yields were achieved with rest intervals of 20 to 28 days. Simulated mixed sheep and cattle rotational grazing on permanent pasture resulted in intermediate (10 to 12%) clover dry matter contributions to total dry matter compared with cattle (15 to 18%) and sheep (5 to 8%). Lamb growth rate was about 35% higher when the clover content of the sward was increased from very low to about 35%.
    • Studies on Pre-slaughter Handling of Pigs and its Relationship to Meat Quality

      Lynch, P.B.; Lawlor, Peadar G; Davis, D.; Kerry, J.P.; Buckley, D.J.; Walsh, L. (Teagasc, 1998-12-01)
      Two quality defects of pork which are affected by preslaughter handling are PSE (Pale Soft Exudative) and DFD (Dark Firm Dry) meat. The incidence of PSE pork is mainly a function of the breed of pig but short-term stressful handling before slaughter and feeding too close to slaughter are also involved. DFD meat is a result of prolonged stressful handling. PSE meat is pale and uneven in colour and exudes fluid making it unattractive in the retail display while dark meat appears stale and is prone to bacterial spoilage. After slaughter muscle metabolism continues and muscle glycogen is converted to lactic acid reducing meat pH. Prolonged stress results in glycogen depletion, pre-slaughter feeding results in elevated levels. Colour may be assessed subjectively by eye or objectively by a meter colour but pH of the meat is closely related to colour and measurement of pH at 45 minutes post-slaughter is frequently used to predict ultimate colour and pH. The objective of this study was to examine pre-slaughter handling practices and their relationship with meat quality (pH, colour). In the first trial, a survey of the amounts of stomach contents in pigs at slaughter in two factories found similar amounts to comparable surveys in France and the UK. It was concluded that most pigs had been fasted for an adequate time before delivery. The relationship between the amount of stomach contents and meat quality in this survey was poor. In the second trial, pigs from the Moorepark herd fed by either a computerised wet feeding system or an ad libitum dry feed system were slaughtered after overnight fasting or with feed available up to loading for transport to the factory, two to three hours before slaughter. There was no difference between feeding systems in meat colour or pH but fasted pigs, on both feeding systems, had darker meat and meat of a higher pH. In the third and fourth trials a survey of transport vehicles was carried out and meat quality of pigs delivered in modern and old-type vehicles was compared. Most trucks examined (78%) were four years old or more. Few had modern hydraulic lifting gear for the top decks. Space allowances during transportation were generally adequate but delays in unloading could, in warm weather, cause stress on pigs. There was little evidence for an effect of vehicle on meat quality parameters but day to day variation in carcass temperature and pH suggested a need for further research on factory influences on meat quality. Feeding of Magneium Aspartate to pigs for the last 5 days prior to slaughter has been shown, in Australia, to have a beneficial effect on meat colour and drip loss. In the final trial in this study Mg Asp had no effect on meat quality parameters.
    • Effect of Pre-and Post-weaning Nutrition and Management on Performance of Weaned Pigs to circa 35 kg.

      Lynch, P.B.; Kavanagh, S.; Lawlor, Peadar G; Young, M.; Harrington, D.; Caffrey, P.J.; Henry, W.D. (Teagasc, 1998-12-01)
      The objective of this project was to examine the factors affecting performance (growth rate, appetite, feed conversion efficiency) of pigs in the stage from weaning to 35 kg liveweight. The study involved three stages, creep feeding during the suckling period, management during the first weaner stage (c. 4 weeks from weaning or 6 kg to 15 kg liveweight) and management during the second weaner stage (c. 15 kg to 35 kg liveweight. Creep feed intake before weaning was low c. 2.5 to 3.0 kg per litter but where it was consumed the response in terms of feed conversion efficiency was good with litter weight increasing in weight by about 1.1 kg for each 1 kg creep consumed. Milk replacer in liquid form was very readily consumed but its preparation and feeding is very laborious. Weaning weight was poorly related to post weaning performance and weaning age seemed to be more critical which is probably a reflection of the greater maturity of older animals. In the first weaner stage, feeding of cooked cereal containing diets was found to have little benefit in pig performance. Acidification of feeds is likely to have only a minor influence on pig performance. An experiment on choice feeding of starter and link feeds did not confirm that smaller pigs require a higher quality diet and, in a choice situation will eat a greater proportion of the more nutrient dense diet. In the second weaner stage, comparison of three commercial weaner feeds with a cereal based control diet showed good performance on all four diets. Pigs fed a high lysine weaner diet grew better in the weaner stage but by slaughter those pigs fed the low lysine weaner diet, after all pigs were fed a common finisher diet, had overtaken them. The high lysine group did, however, have leaner carcasses. Residual effects of early nutrition need to be investigated in more detail including the effect of pregnancy feeding on prenatal development and the relationship between prenatal growth and postnatal growth, in particular development of muscle.
    • Efficacy of curently reccommended control measures for lameness in dairy cows.

      Leonard, Nola; Crilly, Jim; O'Farrell, Kevin (Teagasc, 1998-12-01)
      Lameness is a multifactorial condition, the principal factors influencing its development being genetics, nutrition, environment and management. The objectives of the studies reported here were: (i) To determine the incidence of lameness on selected Irish commercial dairy farms, ii) To identify and to quantify risk factors associated with lameness on Irish dairy farms and (iii) To evaluate the efficacy of recommended control measures for lameness with the aid of information obtained through (i) and (ii). • The average number of animals which became lame per six month period (Jan-Jun or July-December) on 14 commercial dairy farms was between 12 and 16 per 100 cows. On individual farms the figure could be as high as 31 per 100 during any six month period. • White line disease was the most common cause of lameness with sole ulceration being the second most common. • Poor maintenance of roads with little use of top dressing and the presence of concrete roadways on farms were both associated with a detrimental effect on lameness incidence. Thus, prevention of lameness at pasture entails maintaining roads in good condition and, if concrete roads are used for cows, care must be taken to ensure that the junction between the concrete and the dirt road is maintained in good condition and that the concrete is maintained free of grit. • Cubicles on most farms have not been upgraded sufficiently to provide adequate cow comfort. Many are too small for the size of cows housed and bedding is frequently insufficient. Uncomfortable housing conditions resulted in less lying behaviour and more standing half-in cubicles. • Restricted feed space was associated with more lameness. Experimental studies suggested that this effect was likely to be mediated through increased aggression between animals. • Higher levels of concentrate feeding correlated with more lameness. Increasing fibre in the diet in the form of sugar beet pulp appeared to protect against lameness. There was some evidence that feeding maize silage may increase lameness incidence but this effect requires further study. Cows housed in all space-sharing cubicle designs tested showed good lying times. The finding that cows will reduce use of cubicles in order to stand on a soft matted area suggests that even spacesharing cubicles may not always provide sufficiently comfortable conditions for cows. It also reinforces the findings of work at Moorepark and elsewhere that cows do not like standing on concrete in addition to the fact that it can be detrimental to claw health. All of the above findings suggest that lameness incidence could be reduced by maintaining roads in good condition, avoiding the use of concrete if possible, providing comfortable housing conditions and avoiding all design features which reduce cubicle occupancy and which increase aggression between cows.
    • Effects of concentrate distribution pattern on the performance of finishing steer fed silage.

      Keane, M.G. (Teagasc, 1998-12-01)
      The present economic level of concentrate supplementation for finishing steers offered silage ad libitum is in the range 4 to 7 kg per head daily depending on factors such as concentrate costs, type of animal being finished and anticipated carcass price (Keane, 1998). Concentrates are normally fed at a flat rate throughout the finishing period either as one or two discrete meals per day or as part of a mixed ration. In recent years, mainly because of the need to hold cattle until specific dates to collect premia, the practice of varying the level of concentrates throughout the finishing period has developed. Feeding a lower level early on prevents animals being finished before their eligible premia dates, and then if they are not finished as the eligible premia date approaches, the level of concentrates is increased to permit rapid disposal after the retention date has passed. As animals mature and fatten, their rate of gain declines even when energy intake remains constant. This could have an adverse effect on meat quality as there is evidence that a declining rate of gain before slaughter predisposes to poorer quality meat. Furthermore, Mediterranean markets in which Irish beef processors are showing increasing interest require carcasses with muscle which is light red in colour and fat which is white in colour. These colour traits are more likely when animals are fed a high level of concentrates towards the end of the finishing period. The objectives of the present study were 1) to compare different distribution patterns of supplementary concentrates for finishing steers, and 2) to ascertain if there were interactions between concentrate feeding pattern and breed type.
    • Lamb Growth Rate On Pasture : Effect Of Grazing Management, Sward Type And Supplementation

      Grennan, E.J. (Teagasc, 1999-01-01)
      In spring-lambing flocks an important objective is to achieve high lamb growth rate on pasture so that most lambs are drafted for slaughter by September. Lamb growth rate can vary greatly depending on the type of pasture being grazed. A series of grazing trials was carried out to assess the effect of pasture type, sward height, herbage allowance and concentrate supplementation on lamb growth rate pre and post weaning. Sward height was a useful indicator of the suitability of pasture for sheep grazing. A height of about 6 cm was near optimum for set stocking until late May. A decline in lamb growth rate frequently experienced in the month pre-weaning in June can largely be prevented if sward height is increased to 6 to 8 cm, or the flock grazed on aftergrass at a similar height. With rotational grazing, tight grazing to a residual sward height of 4 cm was beneficial in preventing the pasture becoming stemmy in June but reduced lamb weaning weight. Tight grazing in April when pasture is leafy is less restrictive on lamb growth than in June when the base of the sward is more stemmy. Post grazing heights of 4, 5 and 6 cm for April, May and June respectively, are suggested as a guide in order to achieve high lamb growth. There was a response to creep-feeding lambs. When concentrates were offered at 250 g/lamb/day from age 5 to 14 weeks the extra liveweight at weaning was associated with feed conversion ratios of 4.4 to 6.3 Creep grazing increased lamb weaning weight by over 2 kg and facilitated grazing the pastures tightly in June without penalising lamb growth. Lamb growth to weaning was better on pasture not grazed by sheep in the previous year and this benefit was at least partly attributable to lower level of parasites on the pasture. Lamb growth rate on pasture post-weaning varied greatly, from under 100 to over 200 g/day depending on the type of pasture grazed. For set stocking a sward height of 8 to 9 cm was required to maximise lamb growth. For rotational grazing, swards should be grazed down to about 6 cm. However the effect of sward height is modified by previous grazing management, in that tight grazing pre-weaning results in a more leafy pasture and higher lamb growth at comparable sward heights post-weaning. Pasture type also affected lamb growth. There was little difference between old permanent pasture and a mainly perennial ryegrass pasture when grazed at similar sward heights, or when lambs were given similar herbage allowances. However growth rates were considerably higher on grass/clover swards at equivalent allowances or similar sward heights. There was a close relationship between herbage allowance and lamb growth, with highest growth rate achieved at an allowance of about 5 kg of dry matter per lamb per day. Concentrate supplementation of weaned lambs on pasture (at 250 to 550 g/lamb/day) increased liveweight, carcass weight and kill-out proportion. Response to concentrates was slightly better on short grass. Feed conversion ratio for carcass gain ranged from 7 to 12 on short grass, 7 to 20 on long grass and was 14 when concentrates were offered ad libitum. Concentrate supplementation resulted in a higher proportion of lambs being drafted off pasture by late September (90 to 100 %) compared with 60 to 65% for lambs on grass only.
    • Effect of Feeding Mixed Forage Diets on Milk Production

      Fitzgerald, J.J.; Murphy, J.J. (Teagasc, 1999-02-01)
      For dairy farmers involved in winter milk production a high intake of forage is required by autumn calved dairy cows to produce a high milk yield with a moderate level of concentrate supplementation. Since intake of grass silage is often limiting, alternative forages or feeds may be needed to maximise forage intake. In areas not suitable for growing maize alternative forages need to be considered. These could include limited amounts of very high quality grass silage (DMD 750-800 g /kg), grazed autumn pasture or bulky by-product feeds, e.g. superpressed sugar beet pulp. An experiment was conducted involving 5 treatments in which a standard good quality grass silage (S) was partially replaced with either very high quality grass silage, which was either unwilted (U) or wilted (W), ensiled pressed sugar beet pulp (P) or with autumn pasture (G). These additional feeds were fed at a level of 5 kg DM/day to autumn calved cows in early lactation over a period of 8 weeks from late October to late December. The pressed pulp diet (P) included 0.5 kg DM soyabean meal to increase its protein level. The autumn grass was cut daily and fed indoors. The additional feeds were fed on top of the standard silage in individual feeding boxes and the standard silage was fed ad libitum to cows on all treatments. The cows were fed concentrates at 6 kg/day in two feeds on all treatments. The digestibility of the standard grass silage (754 g DMD/kg) was higher than planned and was only slightly less than that of the high quality supplementary silages (783 g DMD/kg). Feeding the U and W silages did not increase total forage intake but did increase milk yield by 1.7 - 1.9 kg/day compared with silage S alone. Milk fat and protein concentration tended to be reduced on the diets containing U and W silages, consequently yield of fat and protein were not significantly increased compared with silage S. Forage intake was increased by 8% (0.8 kg DM/day) when silage S was supplemented with autumn grass and milk yield was increased by 1.5 kg/day without affecting milk composition. Intake of silage was reduced by 37% by feeding grass. Feeding the pressed pulp supplement (P) increased intake of forage (+1.1 kg DM/day), increased milk yield by 2.7 kg/day and also improved milk protein concentration and yield (+121 g/day). Cows gained in liveweight to a similar extent on all diets. It was concluded that feeding pressed pulp with a good quality grass silage had the greatest effect on forage intake and milk production whereas feeding high quality grass silages or autumn grass had a smaller effect. Larger increases in intake and milk production would be expected from these feeds if the standard grass silage was of lower digestibility (~700 g DMD/kg), similar to average quality first cut silage.