Utilisation How much? From 40-50% to 60-80% (depending on previous system and subdivision)

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1 Why rotational grazing? Good individual performance is possible with correct sward height management! But higher production/hectare possible with rotational grazing systems Quantity You will grow more grass! How much 10% to? Why? Grass is rested and given chance to grow to potential Utilisation How much? From 40-50% to 60-80% (depending on previous system and subdivision) Why? More subdivision = more accuracy, more rest, less wasted grass, more flexibility to manage surpluses & deficits Combined effect of more grass + higher utilisation Could almost double utilisable grass on grazed fields

2 What to do with the extra grass? Has to be worth Increase stock Higher Output/GM Spread overheads Limited by resources (sheds etc) Keep same stock on less grassland Grow more crops Less rented land Rent out land Less purchased feed as more and better quality silage can be made For example 400 ha grass with 140 cows and 1000 ewes If utilised an extra 1tDM/ha on 300 ha = 300 t Dry Matter 700 kg cow & calf to 1 yr = 6tDM/yr 300/6 = 50 extra cows Or balance depending on resources, skills, profitability etc 70 kg ewe + 1 ½ lambs = 800 kgdm/yr 300/0.8 = 375 extra sheep

3 Better Quality grass Better quality grass, sward stays green for longer into late summer/autumn, + better silage quality as well 1 D value difference = 20g/day LWG in lambs, 40g/day LWG in cattle D value = ME (energy) Importance of digestibility Higher D value = higher ME + higher intake potential Example 400kg store cattle at grass 70D 11.5ME DMI 2.5% of 400kg =10kgDM x 11.5 = 115 MJ 75D 12.0ME DMI 3.0% of 400kg =12kgDM x 12.0 = 144 MJ (+29MJ/day) Combined effect gives almost 30MJ/day extra, most of which is available for GROWTH

4 Pre grazing height/kgdm/ha 2,500 kgdm/ha for cattle, 2,250 kgdm/ha for sheep (see also 3 leaf grazing diagram) Post grazing height/kgdm/ha (RESIDUAL) 1,500kgDM/ha Importance of correct residual Too long, wasted grass, poor utilisation and sward deteriorates Too short and regrowth is compromised How long to graze a paddock for? Ideally no more than 2 days but 3-4 days maximum or regrowth is compromised Rotation length Determined by pasture growth rate and time required for grass to recover from post grazing cover to Pre grazing cover (750 to 1,500 kgdm/ha) Fast in late spring & early summer (rapid growth), slow in winter (slow/no growth) Pasture growth rate How much kgdm/ha per day is growing? Still grows even when stock on field. Main determinant of rotation length. Measure on farm or use regional data.

5 Rest periods More subdivision = more days rest, higher yield potential and time to regrow 4 paddocks v 10 paddocks 20 day rotation paddocks = 5 days grazing, 15 days rest, regrowth compromised 10 paddocks = 2 days grazing, 18 days rest, regrowth given a chance More days regrowth at higher point on growth curve (grass grows grass) + more flexibility to take out smaller areas But higher infrastructure costs 2extra water troughs + extra fencing

6 Measuring Grass DM supply etc QMS sward stick or rising plate meter (more expensive kit is available!) Rotational grazing lends itself to software/spreadsheet application Dry Matter Intake (demand) Growing and lactating stock 3.0% of liveweight Rules of thumb Dry animal in good condition 2.0% of liveweight To reduce condition 1.75% of liveweight To gain condition 2.5% of liveweight Mob size and paddock size Grazing pressure mob to eat available DM Bigger fields need big group size Smaller groups (practicalities) need to split big fields up What group size can you work with (handling/shearing/bulling groups)? What size are your fields? How often do you want to move stock?

7 Commencing rotational grazing Leader follower Creep grazing Downsides to rotational grazing? Fencing & water Set up wedge by autumn shutting in sequence, grass wintering of sheep or gradual turnout of stock so the fields are not all at same cover. Keep them moving regularly Group up smaller groups in adjacent fields and start moving from field to field Once desired mob size reached commence rotation High priority group lead and lower priority group follow Leaders cream the best of sward, followers tidy up to the desired residual Followers could be non lambed ewe hogs, dry cows. Most other stock high priority Allow lambs or calves to creep ahead of their mothers to get best grass Production/hd can be lower, requires more management input, coccidiosis/worm risk Trace Elements not taken up by faster growing grass. Be aware of these issues! Plenty of equipment on the market. Costs vary but typically 30-50/acre. Must have clean water that refills at a fast-enough rate (especially for cattle)

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