Efficient farming systems to improve nutrient utilisation and profitability Conrad Ferris, Martin Mulholland, Elizabeth Ball and Francis Lively 5 th November 2015 Agri-Food and Biosciences Institute, Hillsborough, Co. Down BT26 6DR,UK

Background  Phosphorus is an essential nutrient for animals (bone, cell structure, energy transfer, milk, meat)  Evidence that water quality is beginning to deteriorate with regards P – action is required  How do we address the problem?  Reduce inorganic P fertiliser use?  Lower overall stocking rates ?  Better management of manures and slurry, and ‘treatment’ options will all help address this problem?  But it would be better if we could reduce the amount of P which is excreted:  Reduced P levels in livestock diets  Feed less ‘P dense’ components of the diet  Improved management and overall efficiency

 Reducing P levels in livestock diets – local research findings  pigs and poultry  beef and sheep  dairy  Reducing P surpluses by improving efficiency Overview of presentation

 Historically, overall P levels in diets for growing pigs was above 6 g/kg (fresh)  Oversupplied?  AFBI conducted a series of studies to investigate the effect of:  lowering overall dietary P level  the use of phytase in pig diets Reducing P levels in diets for growing pigs

The effect of lowering dietary P level on growing pig performance and bone strength parameters Control P (6g/kg) Reduced P (5g/kg) Sig. Feed intake (kg/d) NS LWG (g/d)793763NS FCR NS *Bone weight (g) NS *Load (kg)206204NS t Dietary P of 5 g/kg adequate for growing pigs t Problems formulating lower P diets for finishers tBenefits of phytase inclusion also demonstrated, but need to reduce P levels before phytase addition tResearch needed to demonstrate if further reductions are safe, and interactions with phytase

Reducing dietary P levels for broilers  Phytase use is widespread and has reduced the inclusion of inorganic P through increasing the bioavailability of phytate  Commercial levels of overall dietary P are 4.6, 4.4 and 3.8 g/kg (fresh) for starter, grower and finisher broilers respectively  Can dietary P levels be reduced further?  Study conducted to investigate the effect of reducing P levels on performance and bone strength

The effect of dietary P level on performance of broilers Control P Low P (by 7.5%) Very low P (by 15%) Sig 0-35d DMI (g) NS 0-35d LWG (g) NS 0-35d FCR NS Bone* diameter (mm)2.7 NS Load (kg) NS Dietary P levels can be reduced by 15% Lower P levels need to be commercially validated, and then adopted Scope to reduce levels across other poultry sectors (e.g. Layers, broiler breeders) ? Significant genetic improvements within the poultry sector has substantially reduced P excretions per bird – lessons for other sectors!

Beef and Sheep sector  No local research on P requirements  In general, diets are low in P due to low concentrate usage  Most farms tend to have lower stocking rates  P surpluses generally low  But a large number of farms covering a large area of land – cumulative impact  Many systems operate at a low level of efficiency

Relationship between age at slaughter and carcass weight for prime steers (2013) Age at slaughter (months) Carcass weight (kg)  Huge potential to improve efficiency within the beef sector, and to reduce the environmental impact of beef systems

Intensive beef finishing units?  In general, individual small beef farms tend to have little impact  But what about intensive beef finishing units  May account for >10% of cattle finished in NI  Often associated with a relatively small land areas  Large quantities of by-products are included in rations  Little information available on the P content of rations offered  These farms may pose a risk to water quality?...insufficient information is available to assess risk!

 Average P level in dairy cow concentrates in NI in 2001 was 6.2 g/kg fresh (7.1 g/kg DM)  P was over supplied – but by how much could it be reduced?  4 Year study dairy cows  Diets contained either ‘normal’ or ‘reduced’ levels of P Reducing P levels in dairy cow diets-AFBI research Winter period Normal PReduced PReduction in P (%) Concentrates 6.2 g/kg fr.3.8 g/kg fr.38% Total Diet4.8 g/kg DM3.6 g/kg DM25%

Normal P 4.8 g/kg DM Reduced P 3.6 g/kg DM Sig. DMI (kg/cow/day) NS Milk (kg/cow/day) NS Bone P level (g/kg organic matter) NS Pregnancy rate (%)9283NS Effect of dietary P level on cow performance over lactations 1-4

How far can total dietary P levels be reduced? Clear evidence of deficiency g/kg DM Adequate in some studies, inadequate in others g/kg DM Occasional evidence of inadequacy g/kg DM Adequate in virtually all studies g/kg DM Over-feeding?>3.8 g/kg DM

2001Survey of 50 farms6.2 g /kg fresh (7.1 g/kg DM) Hillsborough study3.8 g/kg fresh (4.4 g/kg DM) 2005NI Industry target5.7 g/kg fresh (6.6 g/kg DM ) 2015Where the NI industry is at present 5.0 g/kg fresh (5.7 g/kg DM ) How far can we safely reduce the P content of concentrates?

Can P levels in dairy cow rations be reduced below 5.0 g/kg fresh?  Yes  But at a cost!  P content of silages need to be considered (extremely variable: 1.6 – 4.8 g/kg DM)  Lower P concentrates may have a role on some intensive derogated farms  Demonstrated in a recent AFBI study involving derogated systems of milk production

Year round housing Winter housing – summer grazing Concentrate intake (tonnes) Energy corrected milk (kg) Phosphorus balance (kg P/ha) associated with two intensive experimental systems P balance (kg P/ha) Cost of moving to very low P concentrates (100 cow herd) £2800£2000  Low phosphorus balances are possible – even with intensive high input herds – but at a cost

Can P levels in dairy cow rations be reduced further?  Yes.....  But greater gains (economic and environmental) can be made by  Making better use of forage, and  Tackling inefficiencies in concentrate feeding  Milk from forage on Benchmarked farms has fallen by 1500 litres during the last 12 years (1550 litres in 2014)  But is milk from forage still important?

Relationship between milk from forage and common margin ( CAFRE Benchmarking ) Yield band (litres) Top/Bottom 25% for milk from forage Milk from forage (litres) Common margin (£/cow) 5000 – 6000Top Bottom – 8000Top Bottom >9000Top Bottom  Strong relationship between milk from forage and common margin

Relationship between milk production and concentrate intake on CAFRE Benchmarked farms ( )

Most efficient and least efficient quartile of farms within each yield bracket (6000 – l)

Calculated P balance on Benchmarked farms (kg P per Ha) Most efficientLeast efficient 6000 – 7000 litres Effect of concentrate use efficiency on P balance within each yield band 7000 – 8000 litres 8000 – 9000 litres 9000 – litres  Huge potential to improve P use efficiency and improve profitability by improving whole farm efficiency  What are the factors that differ between the most and least efficient farms?

Getting more from forage  Achieving optimum yields: Grass varieties Soil pH and drainage Nutrient management, including N  Improve silage quality: Silage quality has not improved in last 20 years! High quality silage offers real potential to reduce concentrate use  Grazing management :Turnout date Pre and post grazing targets Measuring and take action Confidence in grass  High quality forages offer real potential to reduce concentrate use, to reduce P inputs and to improve farm profit

Manage concentrate feeding  How important is concentrate allocation strategy? Feed-to- yield Complete diet Sig. Milk yield (kg/d) NS Milk fat + protein yield (kg/day) NS  Greater spread in performance with feed-to-yield type systems  But mean performance unaffected by system – at a given stage of lactation

Key issues to consider  Getting concentrate level correct is critical  Targets concentrates to cows that will respond  If TMR feeding – batching is critical  Feed-to-yield systems allow ‘precision’ to be brought to feeding  Establish M+ levels  Calibrate feeding systems  Check computer settings – 0.45 kg concentrate/litre milk  Supplement for energy corrected milk, not milk volume  Precision technologies offer opportunity for improved efficiency

Conclusions  Significant progress on pig and poultry side in terms of nutrition and efficiency – potential to improve further?  Room for improvement in beef sector, especially in overall efficiency  P levels in dairy cow concentrates can be reduced further – but at a cost  Improved P efficiency possible through improved forage quality and concentrate supplementation strategies – with potential to improve profitability  The whole livestock sector must continue to reduce its P footprint