How to Feed Cows on Pasture Well, It Depends! Traditional operator trying to save on feed cost –Probably less than 10# pasture for short periods –Assuming quality is similar, not much ration change if any Hybrid Operator –Desire or need for higher yields of milk? –Probably 10-15# pasture for longer periods –Design and balance ration for the higher milk yields? Low Input Producer –Goal of 50% or greater pasture consumption totally over 365 days –Design and balance ration Low protein-higher energy/starch in spring Moderate protein – summer Low-moderate protein –fall 4-10# DM grain

Intake (energy) drives production 75 % of milk production response is related to intake

Milk/Temperature Relationship 2003

“Feed What We Got” Syndrome

Converting Feed into Milk- the Basics It ain’t that complicated but it sure ain’t simple. Ron Belyea 115 ASRC

Spring Pasture DM Intakes

Body Condition Score F M A M J J A S O N BCS

Feeding the Cow on pasture is NOT rocket science

Effect of low energy intake on lactation response Peak lactation affected by energy intake Adequate NEL intake Low NEL intake

What is NDF? Early harvested forage (40 % NDF) Late harvested forage (65 % NDF) Plant cells NDF (cell wall) = neutral detergent fiber Cell Solubles

What about NDF? Affected by: stem formation, stress, senescence Dr Danny Donaghy, pers. comm.

What Controls Intake Rumen fill is a major factor Rumen fill = NDF volume Intake controlled by fill = physical limit NDF limit =.011 X BW NDF limit = 1500 x.011 = 16.5 lbs NDF

NEL –=1.86# 4% FCM NEL –2.4# 4% FCM Net Gain of.54# 4% FCM ????? What about substitution? Soooo if we feed cow 30# NEL –Anticipate energy for 60# 4% FCM –Not accounting for maintenance, body wt gain/loss, etc. If we want to supplement w/ 6# DM NEL –Guestimate 0.5# substitution effect –Suggests 27# pasture and 6# grain = 65# 4% FCM

What happens if you feed 5kg of grain Wales and Doyle, 2003 Grain Pasture

Feeding Cows on Pasture is like Drinking Coffee (if you like sugar and cream)

Get the priorities right 80% of potential gain made by getting the system right System Feed Fine tuning

Pasture TMR Milk (lb/d) 34 lb Kolver and Muller, 1998 } What limits production on pasture? Milk (lb/d) Intake+ 21 (59%) Grazing/walking+ 8 (23%) Urea cost+ 4 (11%) Milk composition+ 2 (7%) Liveweight (4%) 33.5

TAKE HOME MESSAGE Pre and Post Grazing Heights drive Quality Quality drives Intake Intake drives Milk Production Low Cost Milk Production influences Profit Measure; Monitor; Manage

Definitions and Concepts Feed Demand/Pasture Balance –The relationship between what the farm is growing on a daily basis and its current feeding requirements –Example In the previous example 33.75#/day was the feed demand of forage from pasture To maintain average cover of the farm then 33.75#/acre of forage must grow daily

Definitions and Concepts Feed Demand –Amount of pasture forage needed per cow per day above other supplemental feeding (grain, silage, hay) –Example: Stocking rate of 1.25 cows/acre Cow requirement of 38# DM/day Feeding 8# grain and 3# DM corn silage /cow/day Feed Demand of pasture forage is 33.75# (38-(8+3)=27)*1.25=33.75