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Planning a Managed Grazing System -Why and How. Ed Ballard Animal Systems Educator Effingham Center. What Is Management Intensive Grazing. MiG Defined.
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Planning a Managed Grazing System -Why and How Ed Ballard Animal Systems Educator Effingham Center
MiG Defined • A flexible approach to rotational grazing management whereby animal nutrient demand through the grazing season is balanced with forage supply and available forage is allocated based on animal requirements
Grazing Formula Sunlight + Rain + Green Plants = Plant Growth Plant Growth + Grazing Animals = $$$ The Grazing formula involves: • What’s best for the grass • What’s best for the livestock • What moves you toward your goals!!!
M-I-G Principles • Psychological Barriers • No Seed Heads • Rest Periods • Short Grazing Intervals • Match the Animals Needs to the forage values.
The Rest Period • Should vary according to plant growth • In general, must increase as growth rate slows • Relates closely to seasonal forage growth • Need to rotate between paddocks every 3-6 days
Quality Yield Best Time to Graze Forage: Flowering & Seeding Freshly grazed Lush Photosynthesis: Low High Reduced (shading) Energy Reserves: Depletion Renewal Diverted to seed/flower Growth: Slow Rapid Slow
Winter annual (small grain annual ryegrass) Cool-season perennial grasses Warm-season perennial grasses Relative Growth Rate Winter annual (small grain/annual ryegrass) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month Growth curves for cool-season perennial grasses, warm season perennial grasses, and winter annuals.
For rapid regrowth Take half and leave half
1st inch 2nd inch 3rd inch 4th inch Pasture Height lb. DM/ac 1000 800 600 400 200 0 P. Ryegrass WC Orchardgrass Source: Lane 1998
Growth Stages High Composition, Relative Values Medium Low Grasses Leafy Boot Heading Bloom Legumes Leafy Prebud Bud Bloom
Forage Growth Curve Quality Yield Best time to graze
Forage Length and Grazing Efficiency 1. 8” -12”=MAXIMUM INTAKE • 30-90 BITES PER MINUTE 2. Longer forage • Reduces number of bites • Tears off only 8-10 inches
Residual forage required to maintain 2.5% intake for different grazing periods Residual Dry 3000 Matter 2500 (lb/A) 2000 1500 1000 500 0 1 2 3 4 5 6 7 8 Days in grazing period
So how do you manage body condition ? • Intake is most affected by post-grazing residual
Increased animal output • Will not happen overnight
Increased animal output • Will not happen overnight • Will come with time • Improved soil structure and organic matter • Improvement of plant community • Increased management skills
Before Building Fence • Guideline # 1: Flexibility • Guideline # 2: Walk pastures and use maps • Guideline # 3: ??? Number of paddocks
80 60 40 20 0 1 4 8 12 24 Paddock Number Efficiency Grazing Efficiency, %
Impact of grazing efficiency • Square paddocks had 17% higher carrying capacity • On 160 acres, equivalent of adding 27 acres • If land costs $700/acre, value of increased carrying capacity is $18,900 • Or, you could spend up to $118 / acre to improve grazing efficiency and still break even
Benefits of MiG • Reduced production costs • Increased animal output • Improved land use efficiency • Environmental quality • Quality of life
Benefits of MiG Quality of life