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peer-reviewed Reducing electricity consumption in Irish milk production is a topical issue for 2 reasons. First, the introduction of a dynamic electricity pricing system, with peak and off-peak prices, will be a reality for 80% of electricity consumers by 2020. The proposed pricing schedule intends to discourage energy consumption during peak periods (i.e., when electricity demand on the national grid is high) and to incentivize energy consumption during off-peak periods. If farmers, for example, carry out their evening milking during the peak period, energy costs may increase, which would affect farm profitability. Second, electricity consumption is identified in contributing to about 25% of energy use along the life cycle of pasture-based milk. The objectives of this study, therefore, were to document electricity use per kilogram of milk sold and to identify strategies that reduce its overall use while maximizing its use in off-peak periods (currently from 0000 to 0900h). We assessed, therefore, average daily and seasonal trends in electricity consumption on 22 Irish dairy farms, through detailed auditing of electricity-consuming processes. To determine the potential of identified strategies to save energy, we also assessed total energy use of Irish milk, which is the sum of the direct (i.e., energy use on farm) and indirect energy use (i.e., energy needed to produce farm inputs). On average, a total of 31.73 MJ was required to produce 1kg of milk solids, of which 20% was direct and 80% was indirect energy use. Electricity accounted for 60% of the direct energy use, and mainly resulted from milk cooling (31%), water heating (23%), and milking (20%). Analysis of trends in electricity consumption revealed that 62% of daily electricity was used at peak periods. Electricity use on Irish dairy farms, therefore, is substantial and centered around milk harvesting. To improve the competitiveness of milk production in a dynamic electricity pricing environment, therefore, management changes and technologies are required that decouple energy use during milking processes from peak periods.

End of project report 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. Teagasc acknowledges with gratitude the support of Dairy Levy Funds and EU Structural Funds (FEOGA) in financing the research programme.

End of project report The results highlight the importance of BCS in achieving good reproductive performance. The likelihood of reproductive success was best predicted by BCS around the time of breeding and, for cows calving in good BCS (3.0 or greater) the level of BCS loss between calving and first service. A low BCS pre-calving (3.5) results in excessive BCS loss (>0.5) post-calving. On the basis of these findings a pre-calving BCS of no greater than 3.25 is a sensible target for pasture-based spring calving systems in Ireland. It is necessary to maintain BCS at 2.75 or greater during the breeding season, and loss of body condition between calving and first service should be restricted to 0.5 BCS units. National Development Plan (NDP)

peer-reviewed Two experiments (E1 and E2) were carried out to examine the effects of sward type (ST) on dairy cow performance. Applying grazing pressures (GP) in spring/early summer of 6.35, 4.24 and 3.53 cows/ha in E1, and 6.06, 5.05 and 4.03 cows/ha in E2, created the different ST. From summer to autumn, two stocking rates (SR) were applied to each sward, i.e., high (HR) and low (LR). As GP was reduced, the swards were characterised by progressively higher herbage mass of lower organic matter digestibility (OMD) and live leaf (LL) proportion, termed high (HQ), medium (MQ) and low (LQ) quality. There was no interaction between ST and SR for any animal performance variables except for grazing time. Mean diet OMD was 0.816, 0.803 and 0.794 (s.e. 0.0029) in E1, and 0.793, 0.780 and 0.772 (s.e. 0.0021) in E2, for HQ, MQ and LQ, respectively. The corresponding values for LL were 0.785, 0.740 and 0.709 (s.e. 0.0121) in E1, and 0.825, 0.790 and 0.759 (s.e. 0.0095) in E2. Milk yield per cow was 13.2, 12.2 and 10.6 (s.e. 0.55) kg in E1, and 18.4, 17.5 and 16.2 (s.e. 0.32) kg in E2, for HQ, MQ and LQ, respectively. Milk yields were 11.1 and 12.9 (s.e. 0.46) kg in E1, and 16.4 and 18.3 (s.e. 0.26) kg in E2, for HR and LR, respectively. There was no effect of ST or SR on milk composition or body weight gain. Herbage organic matter intake was 12.8, 12.5 and 11.1 (s.e. 0.28) kg in E2, for HQ, MQ and LQ, respectively. The corresponding values were 11.4 and 12.9 (s.e. 0.23) kg for HR and LR, respectively. The results show that milk yield of springcalving dairy cows is higher in summer when high rather than low stocking rates are applied in spring/early summer. The increased milk production is attributed to higher intake of herbage of higher nutritive value.

peer-reviewed Two experiments (E1 and E2) were carried out to examine the effect of grazing pressure (GP) in the early part of the grazing season on subsequent sward composition. Three GP levels, equating to 6.35, 4.24 and 3.53 cows/ha in E1, and 6.06, 5.05 and 4.03 cows/ha in E2, were used. The GP treatments were applied between April and July in E1, and April and June in E2. As GP decreased different swards, termed high (HQ), medium (MQ) and low (LQ) quality, were created. The post-grazing sward heights at the end of the GP periods were 6.6, 10.5 and 14.6 (s.e. 0.78) cm in E1, and 5.9, 8.8 and 11.4 (s.e. 0.39) cm in E2, for HQ, MQ and low LQ, respectively. Organic matter digestibility coefficients for herbage from the HQ, MQ and LQ swards during the subsequent grazing cycles averaged 0.770, 0.729 and 0.702 (s.e. 0.0055) in E1, and 0.761, 0.731 and 0.711 (s.e. 0.0038) in E2, respectively. Average live leaf proportions of the HQ, MQ and LQ swards were 0.583, 0.427 and 0.329 (s.e. 0.0193) in E1, and 0.600, 0.474 and 0.362 (s.e. 0.0155) in E2, respectively. GP had a significant effect on the proportion of grass area categorised as short grass (SG). The proportions of SG area in HQ, MQ and LQ were 0.711, 0.579 and 0.445 (s.e. 0.0106), respectively, in E1, and 0.700, 0.556 and 0.441 (s.e. 0.0133), respectively, in E2. Pre-grazing herbage mass (dry matter above 45 mm) was 2,065, 2,736 and 3,700 (s.e. 144.1) kg/ha for HQ, MQ and LQ, respectively, in E1 and 2,688, 3,735 and 4,722 (s.e. 145.0) kg/ha for HQ, MQ and LQ, respectively, in E2. The results show the importance of early season grazing pressure in creating a leafy high-digestibility sward for the remainder of the grazing season.

End of Project Report 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.

End of Project Report The objective of this study was to investigate the potential differences among different dairy cow breeds across two feeding systems on milk production, udder health, milking characteristics, body weight, body condition score, hormone parameters, ovarian function, survival and overall reproductive efficiency. The breeds investigated included Holstein-Friesian (HF), Montbéliarde (MB), Normande (NM), Norwegian Red (NRF) and Holstein- Friesian × Montbéliarde (MBX) and Holstein- Friesian × Normande (NMX). Selection within the HF breed has, until recently, been predominantly for milk production with little or no direct selection for functional traits other than those correlated with superior type. The MB and the NM have been simultaneously selected for both milk and beef production in the past. The NRF were imported as calves and come from a more balanced total merit index incorporating production and cow functionality since the early 1970s. The dairy cow breeds were grouped into blocks of two within breed groups and randomized across two spring-calving grass-based feeding systems: low concentrate feeding system (LC) and high concentrate feeding system (HC). Those on LC feeding system were offered approximately 530 kg/cow over the total lactation, while those on HC feeding system were offered approximately 1030 kg/cow. There was no genotype by environment interaction observed for any of the milk production, BCS, BW, udder health, milking characteristics, reproductive performance or feed intake/efficiency parameters investigated. Compared to the MB and NM, all other breeds had higher total lactation milk, fat, protein and lactose yield, with the HF having the highest. Animals on the HC feeding system had higher total lactation milk, fat, protein and lactose yield. Compared to the NRF, SCS was higher for the HF, NM, MBX and NMX breed groups, while SCS of the MB was not different. The NM and MB had lower AMF compared to all breeds. The crossbreds achieved the higher AMF. The NM had the lowest PMF, while that of the crossbreds were higher compared to all breeds. Milking duration was not affected by breed. Differences between breeds for AMF, PMF and MD were not apparent after adjustment for milk yield. Animals offered a HC diet had higher AMF, PMF and MD compared to those on the LC feeding system. Somatic cell score did not differ between the feeding systems. The interaction between breed and milk yield influenced SCS, AMF, PMF and MD thus implying that for each unit increase of milk yield by breed, the response in SCS, AMF, PMF and MD was different for some breeds. The response in SCS was similar for the NRF, MBX and NMX, while MD was similar for the MB and MBX. The effect of one unit increase in daily average milk yield caused a favourable decrease in SCS; however a one unit increase in PMF and MD did not influence SCS. No interactions were observed for breed with any milking characteristic on SCS. The HF had the lowest BCS, the MB and NM the highest, while the NRF, MBX and NMX were intermediate. The NRF had the lowest BW; the NM had the highest while the other breeds were intermediate. The NRF had increased likelihood of SR24, PREG1, PREG42 and FINALPR and greater survival compared to the HF. Both MBX and NMX had shorter CSI and CCI and were more likely to be pregnant at the end of the breeding season, thus had higher survival rates compared to the HF; however heterosis estimates for these traits was not significant, likely due to the small data size. Feed system did not influence reproductive performance of the different breeds. Breed of dairy cow did not influence any of the ovarian parameters studied. Breed of dairy cow did not influence insulin or IGF-1 concentrations at any sampling period. Breed significantly effected gestation length, calf birth weight and calving ease score. The NRF had the shortest gestation, lightest calves and least calving difficulty. Genotype had a significant effect on estimated dry matter intake, being highest with the HF, MBX, NMX and lowest with NM and NRF. Genotype also had a significant effect on yield of milk solids per kg of DMI. The highest yield of milk solids per kg of DMI was achieved with the NRF, HF and MBX. Comparisons between genotypes reveal that estimated residual feed intake estimates were lowest (most favourable) for the NRF, compared to other genotypes with the exception of HF.

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

End of Project Report The potential of Irish soils to grow grass throughout the year and success in utilizing grass are key factors affecting output and profitability of dairy production systems (Shalloo et al., 2004). In the Northeast region of Ireland, the potential grazing season is shortened due to impeded land drainage, topography, high rainfall and northerly aspect. The main focus of the Ballyhaise research programme is to develop more sustainable production systems suitable to the limitations of the region with a specific focus on grass growth and utilization. Progress in these technologies will improve the competitiveness of dairying in the Northeast region. We are also now faced with a new economic environment with market forecasts predicting a steady decline in dairy product prices for Irish dairy farmers while input prices continue to increase. It has been shown from previous studies that dairy farmers need to expand and/or increase the efficiency of their dairy operation to maintain their real farm incomes over the coming years (Breen and Hennessey, 2003). It is likely that land purchase price will continue to be high in future years. Firstly, dairy farmers can continue at their current level of production and efficiency, and suffer a decline in farm profit as milk price falls. It is likely that greater amounts of milk quota will become available in the coming years; therefore many dairy farmers will have the option to increase production. Expansion opportunities will be limited by the key constraints such as labour supply and cost, capital cost, milk quota availability and price and availability of land around the milking parlour. Labour efficient work practices will have to be adopted on farms to allow one operator to manage a greater number of cows. The objective of this experiment was to examine the effect of two divergent pasture-based systems of milk production on animal performance over a two-year period and to subsequently describe the optimum system for dairy farmers in the Northeast region both now and into the future.

peer-reviewed An experiment was conducted to examine the effects of herbage mass [HM, based on regrowth intervals of 35 (T) and 21 (S) days] and herbage allowance [HA, 20.2 (H) and 12.7 (L) kg organic matter (OM)/cow] on herbage OM intake (OMI), dietary composition and ingestive behaviour of dairy cows. Four groups of three cows each were used in a 4 × 4 greco-latin square design along with four oesophageal-fistulated cows. The treatment periods were 7 days and the squares (SQ) were repeated three times in a balanced way. The experiment was conducted from 11 April to 3 July 1986. The HM (organic matter) above 3 cm was 3064, 3472 and 3515 kg/ha for T and 2395, 1113 and 2396 kg/ha (s.e. 94) for S, for SQ 1 to 3, respectively. Organic matter digestibility (OMD) was 842, 799 and 778 g/kg for T, and 851, 842 and 804 g/kg for S (s.e. 0.9), for SQ 1 to 3, respectively. Sward height (cm) after grazing was 8.5 and 7.6 for T and S, and 9.6 and 6.5 for H and L (s.e. 0.18), respectively. OMI was 15.2, 14.8 and 15.2 kg for TH, 12.3, 11.9 and 10.7 kg for TL, 15.8, 14.8 and 14.5 kg for SH and 11.9, 11.1 and 11.2kg for SL (s.e. 0.24), for SQ 1 to 3, respectively. The OMD of the diet was closely related to proportion of live leaf in the diet and sward OMD. Average biting rate increased with decreasing HM (R2 0.65). Grazing time was 8.93, 9.11 and 9.06 h for TH, 8.13, 7.96 and 7.91 h for TL, 8.96, 9.59 and 9.29 h for SH and 8.56, 9.36 and 8.52 h for SL (s.e. 0.155), for SQ 1 to 3, respectively. Multiple regression analysis showed that OMI was significantly related to HM (+0.48 kg/t), OMD of the sward (+0.18 kg per 10 g/kg) and pre-experimental milk yield (+0.37 kg/kg) (R2 0.89). The increase in OMI with potential milk yield, as indicated by pre-experimental yield, accounted for 0.80 of the supplementary energy requirements. National Development Plan 2000-2006

End of Project Report The overall objective of this project was to determine, following four experiments, the effects of genetic merit for milk production, dairy cow breed and prepartum feeding on reproductive physiology and performance. In the present experiments, the high proportion of Holstein- Friesian genes played a more important role in reducing reproductive performance than milk production. Significant breed differences in reproductive performance were detected. European Union Structural Funds (EAGGF)

End of Project Report Visual assessment (>4 cm) was found to be the preferred method of pasture mass estimation. Grass budgeting with the use of grass cover measurement, was found to be the most effective aid to good grazing management. Closing farm grass cover in late November/early December should be 350 to 450 kg DM/ha with a range in covers of 200 to 900. Target farm grass covers of 550 to 600 kg DM/ha at turnout at stocking rate of 2.75 cow/ha. Pre-grazing yields at turnout should not be less than 1000 kg DM/ha, giving daily grass allowance of not less than 5 kg DM/cow. The available grass supply in Spring should be budgeted so as to finish the first grazing rotation between the 10th-20th April (grass supply equal grass demand). During the main grazing season (May to August), grazing grass cover should be maintained at 900 to 1000 kg DM/ha or 200 to 240 kg DM/cow. Pre-grazing yield should be maintained at 1800 to 2000 kg DM/ha, with post-grazing residuals at 150 to 200 kg DM/ha (5.5 to 6.5 cm post-grazing height). Stocking rates of greater than 4.5 cow/ha on the grazing area in May/June mostly resulted in inadequate grass supply at some periods over that time. Rotation length can be increased from 21 days in mid/late August to 35 days in late September, allowing grass cover to increase to 1100 to 1300 kg DM/ha. Last rotation should be 25 to 35 days, with first paddocks rested from the 10th to 15th October. Greater use of grass measurements at farm level will allow dairy farmers to obtain a greater proportion of the dairy herd’s feed demand from grazed grass, and higher cow performance. Teagasc acknowledge with gratitude the support of Irish Fertiliser Industries, FBD Trust and Dairy Levy Farmer Funds in the financing of this research project.

End of Project Report The rate of genetic improvement in Ireland up until the mid-80’s was low (approx. 0.5% per year) compared to North America where genetic merit for milk production was increasing by 1.5% per year (Funk, 1993). Since 1985 the rate of genetic improvement increased markedly to about 1.5% per year in 1992 (Coffey, 1992). This high rate of genetic progress has mostly been achieved through the importation of North American and European genetics. The relative merit of these sires has been obtained from the performance of their progeny in systems of milk production which differ greatly from those operated in Ireland. The term “high genetic index” (HGI) is used to describe a cow, which as a result of selection, is generally predisposed to produce significantly more milk than a cow of lower merit status. Studies from New Zealand have shown that cows of high “genetic index” at pasture, produce more milk (20 to 40%), consume more herbage (5 to 20%), were more efficient convertors of food into milk (10 to 15%) than lower merit cows (Holmes, 1988). However, these “high” genetic index cows would be considered “low” when compared to present-day genetics. Recent results from Langhill (Veerkamp et al., 1994) have shown that increasing genetic index results in major increases in feed efficiency, reflecting increases in milk yield with cows fed indoors on silage/concentrate diets. There is little information available on the performance of present-day HGI dairy cows, on seasonal calving, grass-based systems of milk production