Securing sustainability

• Greenhouse gas (GHG) emissions
  • From agriculture, they were the same in 2021 as they were in 1998.
  • Dairy cow numbers are the same now as they were in 1984.

Cow welfare

• • Irish cows graze outdoors for 75% of the year.
  • The key animal welfare indicators are:
    • Lameness: A recent survey showed that only 6% of cows had sub-optimal mobility, while only 1% showed severe sub-optimal mobility;
    • Somatic cell count (SCC) has declined significantly over the last 10 years to 180,000 now; and
    • The number of calvings per cow per year has increased from 3.3 in 2014 to 3.6 in 2022.
• Calf welfare
  • Calves produced by the dairy herd provide the beef industry with a significant opportunity to reduce GHG emissions per unit of product.
  • In 2023, there were 300,000 (projected to be 800,000 in 2029) sexed semen dairy straws available, which will result in 100,000 fewer male dairy calves with the consequential increase in dairy-beef calves.
• Carbon footprint
  • For the period 2017-2019, the carbon footprint for Irish milk was 0.97kg CO₂ (the last global figure available is 2.4) per kilogramme of milk fat and protein corrected milk yield (FPCM) and, when carbon sequestration is included, it is approximately 0.86.
• Ammonia (NH3) emissions
  • Agriculture accounts for 99.4% of all national NH3.
  • In 2018, Ireland produced 135,200 tonnes versus the target of 116,000 tonnes of NH3.
  • Average nitrogen (N) usage decreased by 14%.
  • We are making some progress on this front due to decreased livestock numbers, reduced fertiliser N, and low emission slurry spreading (LESS).
• Water quality
  • Water quality has deteriorated slightly over the last number of years but has begun to show positive signs.
  • Water footprint: A recent survey showed the consumption of six litres of water per kg FPCM; this compares very well with Australia and the US, where consumption is 108 and 125, respectively. We can improve on the six litres by reducing leakages, recycling plate cooler water, using high pressure washing to clean yards.
• Biodiversity
  • Side trim hedges from a wide base to a triangle profile; maintain riparian buffer strips along streams and riverbanks. Quantity these for your farm and make a plan to increase.
  • 54% of Irish surface water is classified as good or high compared with 44% in the EU.

92% of Irish groundwater has good status compared with 80% in the EU.

Dairy systems: farm today with tomorrow in mind

• Irish dairy sells 1.7 million tonnes of product to over 130 world markets. The average herd size is now 93 cows.
• The following comprise the target performance indicators necessary to achieve a sustainable dairy income in a sustainable environment:
  • EBI: €225+;
  • Mature herd (number of calvings/cows): 4.5+;
  • Optimum soil fertility (% farm area): 100%;
  • Fertiliser N (kg/ha chemical N): less than 150;
  • Calving rate (% calved in six weeks): 90%;
  • Grazed pasture in diet: 70+ %;
  • Pasture utilised (t DM/ha): 13.0 tonnes;
• Three key management practices dairy farmers must focus on to future-proof their businesses

1. Refocus on prudent financial management:

• With input cost inflation being 41% over last two years, farmers must focus on cost. Farmers should get multiple prices when sourcing farm inputs.
• Feed cows based on the following relative costs of feeds.
  • Grazed grass 100
  • Grazed grass-white clover 98
  • Pit silage – two-cut 225
  • Baled silage – two-cut 250
  • Purchased concentrate 500
  • In summary, pit and baled silage are 2.5 times more expensive than grazed grass while meal is five times more expensive. The target is 70% grazed grass in the cow’s diet. This equates to 265 days of herd grazing days and feeding 500kg meal per cow per year.

2. Achieving appropriate stocking rates (SR):

• Being stocked at the appropriate SR for the farm will result in:
  • Minimising external feed and capital costs;
  • Reduced workload; and
  • Minimising environmental impact.
• Unfortunately, while there has been miniscule increase in overall SR, the SR on the milking platform (MP) has increased substantially to 2.8+ cows per hectare. And there was no real increase in pasture utilised per hectare. This resulted in:
  • Increased purchased meal and silage;
  • Increased labour costs; and
  • Increased capital cost.

The result being that overall costs increased 1.6 times the feed costs alone. Therefore, if growing 13 tonnes of grass on MP, the suggested overall SR is 2.4-2.5 cows/ha and 2.7 cows /ha on MP. Farming above these targets is considered to be farming ‘marginal cows’. They have to be fed by total purchased/imported feed, in other words, a total mixed ration (TMR) diet. Research in Ireland and New Zealand has shown a linear decline in profitability as SR increases, as well as increased nutrient losses.

3. Simplifying workload to achieve a sustainable work-life balance on-farm.

• Become a 50-hour-per-week farmer. A survey shows that the most labour-efficient farmers work 51 hours per week compared with 72 for the least efficient. They generally start at the same time – 7pm – but the least efficient farmers finish at 8pm (approx.) – 1.5 hours later than the best farmers.
• The big labour-demanding tasks are milking (31% of time) and feeding calves (20% of time).
• A 16:8-hour milking interval puts structure to one’s day and reduces the working day.

Sustainable and responsible breeding and reproductive programmes

• Optimal breeding and reproductive programmes contribute approximately half of the gains in performance on most farms,
• Sexed semen is a must-use. The following strategies were suggested to maximise success with sexed semen.
  • AI bulls
    • Pick the highest EBI bulls.
    • Use a large team.
• Dams: Use the top 50% of herd based on EBI
  • Heifers
    • - Target liveweight and BCS 3.25+.
    • - Cycling regularly.
  • Cows
    • - Choose from lactations 1-4.
    • - Must be calved greater than 50 days’.
    • - BCS of 3.0 or greater.
    • - Cycling regularly.
    • - No post-calving disorders or uterine disease.
• When to use?
  • During the first three-weeks of breeding.
  • Within the first 10 days, if possible.
• Timing of AI
  • 14-20 hours after the onset of heat.
• Fixed time AI
  • Costly, but minimises risk.
  • Facilitates targeted use of sexed semen on mating start date (MSD).
  • Using FTAI on heifers, there was an 18% increase in pregnancy by delaying AI by eight hours after the last GnRH injection.
• Straw handling on the day
  • Organise sexed semen straws into one goblet.
  • At max, thaw two sexed semen straws at a time.
  • Thaw straws at 35-37 degrees centigrade for 45 seconds.
  • Load straws into pre-warmed AI guns and keep warm.
  • Deposit semen into uterine body.
  • Complete insemination within five minutes.
• Using EBI, choose bulls and cows for replacements with a genetically good carbon footprint – new to EBI.
• The commercial beef value (CBV) of calves will be a game changer; therefore, dairy farmers must use dairy-beef AI bulls.
  • Because of genetic improvement for dairy traits on dairy farms, over the last 10 years, the beef traits of the offspring to a dairy dam and sire have disimproved.
  • Consequently, dairy farmers must now choose a sire with high beef traits and use the DBI to choose beef bulls for non-replacement calves on farm. 
• The use of in vitro produced embryos from elite cows and AI bulls will facilitate future genetic gain to counteract fewer male dairy calves.
• We now have genetic days for each and AI bull for somatic cell count, lameness, mastitis and recently added TB and liver-fluke.
• Every €10 increase in herd EBI results in 1% reduction greenhouse gas per kg milk solids.
• COW on the ICBF site makes identifying cows for culling easier, because it predicts the cows that have greatest future potential profit in the herd. An important tool to now use if destocking because of the new regulations.
• The benefits of genomic DNA testing are enormous: it predicts an animal’s genetic potential at birth, identifies genetically elite animals, verifies parentage (mistakes are made at calving), animals with genetic defects or beneficial genes are identified.
  • You will be able to avoid using sexed semen on cows or heifers you will be selling.
  • Your herd may have some elite cows that could be used for embryo transfer for the provision of future AI bulls. 
• Increasing the feed conversion efficiency of a herd: All you need is cow body weight (BW) in June (or convert the cow maintenance figure to BW) and mild recorded milk solids per cow/year (MS).
  • In the survey animals varied from 0.42-1.47kg MS/kg BW; it varied between herds from 0.73-1.14. 
  • The high-efficient Friesians and Jersey-Cross gave 1.06 and 1.21kg MS/kg BW.
  • This information will allow you breed your replacements from your most efficient cows.
  • This study validates the significant improvement farmers can make within their herds to get higher MS per cow from the feed input available.
• Automated heat detection can improve heat detection and decrease time and cost of it. But investment in same depends on, herd size, current herd performance, time devoted to it, technology cost and capabilities. 

Grassland

• The key factors that influence grass yield per hectare are:
  • Soil fertility
    • Whole farm must be over 6.3pH, and be in Index 3 or 4 for phosphorous and potash.
• Whole farm reseeded to the best grass varieties
  • Reseed 10% per year once the farm has all ‘new’ grass.
•   Achieving 10 grazings per year
  • Each extra grazing increases yield by 1,300-1,600kg DM/ha.
• Achieving target covers throughout the year
  • 900kg DM/ha opening AFC in February.
  • 550-600 kg DM/ha AFC in early April.
  • 160-180kg DM/LU in mid-season.
  • 1,100kg DM ha in mid-September and, from mid-August rotation. length, must increase by two days/week to 40-day rotation on October 1.
  • Closing AFC of 650-750 on December 1.
• The key factors driving grass utilisation are
  • Stocking rate and supplementary feed.
  • If growing 14 tonnes/ha, the appropriate SR is 2.5 cows/ha while feeding 500-700kg meal/cow.
  • The nitrogen in grassland farming comes from
  • The soil in the form of background N (100-200kg/ha/yr).
  • White clover through N fixation (approx. 100kg N/ha contributed).
  • Applied N by way of chemical or slurry.
  • In Moorepark and Clonakilty the overall N supplied, kg/ha, by these three sources was 405 and 470, respectively, for a grass only sward and a grass-clover sward.
  • Nitrogen use efficiency is only 35% when pH, P and K are very low but it improves to 63% when all three are on target.
• Clover (20% content) will increase the kilogramme of milk solids by 20kg, increase nitrogen use efficiency by 18%, from 40% to 58% and reduce N surplus/ha 78kg to 63; nationally, the N surplus is 176kg N/ha.
  • Over-sowing in April-May works if conditions are ‘right’ and yielded 13.3 v 9.9 t/DM/ha when compared with direct reseeding in the year of sowing.
  • On clover 150 farms, data for 2020, 2021 and 2022 showed
    • That farm gate N efficiency improved from 31% to 33% and 39% year-on-year.
    • Chemical N, kg N/ha, use decreased from 232 to 206 to 158.
    • Nitrogen fed through meal (kg N/ha) increased from 41 to 43 to 52 (worrying).
    • Area (%) under clover increased from 10% to 45% to 64%.
    • Herbage production (t DM/ha) decreased from 14.4 to 14.1 to 13.2.
  • White clover swards
    • Increase cow daily DM intake (+0.5-1.1kg), milk yield by +1.1-1.3kg) and milk solids (+0.07-0.11kg).
    • Can fix up to 200kg N/ha (162 units/acre).
    • On wetland type soils, clover performs as well as perennial swards (PRG)
    • Yielded the same amount of grass 12.8 tonnes on 91kg N/ha less.
    • Feeding 456kg more meal in this trail across both clover and PRG swards only yielded 31kg MS/cow more.
    • Clover can lower the carbon footprint by 25%.
    • Bloat must be managed by letting all cows out to graze together, 12-hour blocks, bloat oil, addition of fibre, grazing high covers in September and extra fibre (2kg DM/cow of wilted silage/haylage 30-40% DM) in October when lower covers are being grazed. 
• Protected urea grew the same amount of grass as CAN and 455kg DM/ha more than urea but with much less environmental losses. In the same trial, 250kg N/ha grew 2.2t DM/ha more grass than 150kg. 
• Applying 60kg N/ha (compared with 30 or 90) in two applications (33:66 ratio February and March) provided the optimum combination for DM production, N response and N recovery.
• Silage feeding during the first six-weeks in spring had very little effect on yield, % F or % P, compared with having to feed it during the following six weeks.
  • Greater grass DM intakes and reduced silage feeding in early lactation resulted in lower methane emissions, methane intensity and methane yield. 
  • The quantity of silage required depends on milking platform (MP) stocking rate and tonnes of grass grown on MP.
    • When growing 12t DM/ha on MP and stocked at 2.5 V 3.2 cows/ha.
    • 52% of silage will have to be sourced off MP compared with 75% for the 3.2 stocking rate.
    • 44% V 56% quality silage will have to be made because milking cows at the higher SR will be on silage for longer; dry cows need 68-70% DMD silage while milking cows need 74+% DMD.
    • The annual silage (t DM) required per cow will be 1.33 for the 2.5 and 1.69 for the 3.3 stocking rate; in other words, 1.8 tonnes/cow more.
    • For the higher MP stocking rate a farmer will require approximately 1 tonne DM per cow while only 0.5 tonnes are required for the low SR. 
  • First-cut silage cutting date influences yield and DMD
    • Going from May 26 to June 6 cutting increases yield by 0.9t DM/ha but, DMD is reduced from 73- 65%.
    • There is very little difference in the cost per utilisable ton DM.
    • Generally, if the second cut is taken in late July (it must be to extend the grazing season), there is no difference in overall yield between taking the first cut early or late. But there is much more digestible feed/energy available by an early first cut system.
• Red clover silage, not really suitable for grazing, can produce high yields of silage without any N because it can fix in excess of 300kg N/ha but it must be cut every six to eight weeks. It should be seriously considered for off-milking platform silage.
  • It needs a pH of 6.5+, be index 3 and 4 for P & K. Taking four or five cuts of silage results in K being depleted by 300-375kg/ha. Therefore, all slurry and an extra K will be required to maintain K indices at 4.
  • Sulphur (S), where necessary, should be applied using 8% Super or through compound.
• Reseeding
  • Do 10% of farm every year in April. May or early June; it cost €750/ha approx.
  • There is no loss of yield for that field if sown on those months,
  • Select varieties from the pasture profit index (PPI), sowing 25-28kg grass plus 2.5-5kg medium leaved white clover/red clover.   
  • Multispecies: The inclusion of white clover is crucial to increase their DM production. Research (two years) indicates that they are comparable to ryegrass pastures or ryegrass/clover mix in terms of yield, they require fewer fertiliser applications and increased milk solids/cow.

Environmental Sustainability

• Participate in the Teagasc free Signpost programme.
  • All technologies and practices, if implemented, will both improve the environment and farm profitability.
  • The key ones are
    • Use all protected urea as a source of N.
    • Whole farm must be optimum for pH, P and K.
    • Spread slurry at advised tome with LESS slurry equipment.
    • Improve herd genetics (EBI &DBI), so that:
    • - Replacement rate is reduced;
    • - Age at beef slaughter is reduced; and
    • - And genetics is improved year on year.
    • Incorporate clover.
  • Attend the Teagasc Signpost demonstration farm walks.
  • Join the AgNav Sustainability Programme, a digital platform on ICBF/Teagasc sites that will help commercial farms monitor their environmental performance for carbon (CO₂) and ammonia (NH₄).
• Sustainability report 2021
  • Economic indicators
    • Dairy farms had three to four times higher incomes than cattle farms.
  • Environmental indicators
    • Dairy farms had two to five times higher greenhouse gas and ammonia emissions than other farm enterprises.
    • But the trend was reversed per Euro of output.
    • Consoling, CO₂ and NH₄ emissions decreased between 2014 and 2021 (on three-year rolling averages).
  • Social indicators
    • Dairy farmers are more socially sustainable with lower household vulnerability, have a better age profile and better agricultural education but are at risk because of isolation and long working hours.
• Enteric methane (fermentation within the animal’s rumen) accounts for 63.1% of Ireland’s total greenhouse gasses, and it has to be reduced by 25% by 2030.
  • Methane from cows (g/day) is lowest in spring, increasing significantly in June and remaining such for the remainder of the season.
  • Research measured enteric methane is 9% lower than that used presently in the greenhouse gas inventory.
  • Feed additives will reduce enteric methane but need to be in the diet consistently – as of now that is not possible in pasture-based systems.
• Research has shown that low-emission fertilisers (nitrous oxide) can result in 40 per cent reduction in nitrous oxide and can be achieved by using pro-urea, 18:6:12 or 10:10:20 but 24:2.2:5 was less efficient, as were some other high N compounds.
• Hedgerows:  They store carbon in wood and leaves above ground but also below ground in the roots and in decomposing litter. The amount of storage depends on width, height, species, and structure and especially management regime.
• Carbon organic stocks in Irish grassland soils are estimated to contain 30 years worth of carbon emissions – 1,800 million tonnes of CO₂. However, as of now no baseline soil organic carbon has been determined.
• Sow native trees on farm where there is a high risk of P loss so as to protect water.
• Nitrate loss to rivers has many sources, such as, soil, clover, chemical N, urine patches and soil mineralisation.
  • Avoid applying N to soils when it is not needed.
  • When water is moving through the soil profile or on the surface.
  • Weather and soil type have a significant influence on nutrient loss to water and can override source pressures (farming intensity).
  • There is also a time lag between farming pressures and improved water quality.
  • Imposed measures need time to be adopted by farmers because practice adoption is slow.
• Improving N use efficiency through breeding – Teagasc is working on this.
  • Of the N eaten by the cow she uses it to:
    • Produce milk protein, milk urea N;
    • Protein in meat; and
    • And some goes to waste in the environment by way of urine (40%) and faeces (30%).
  • But some cows are 10% more N efficient, producing 8.5kg N/yr. less than other cows; hence, the role of genetics.
• The way we manage our soils strongly impacts below ground biodiversity.
  • The more diverse grassland swards can have a positive effect on soil biology and functions; hence the case for legumes, herbs or multi species swards.
  • Get the Teagasc self-assessment programme on biodiversity management practices from Teagasc.

“For every animal displaced from the Irish beef herd, 7-8 tonnes of carbon will be added to global emissions.”    

Paul Crossan, Teagasc.