FEEDING METHODS
Introduction

Things to know
The nutritional value of feeds
 Animal requirements of nutrients
 Nutrients intake
 Availability of feed ingredients

Supply
Demand
Cont.


Energy content of the diet
Balance among nutrients
Example:
A 70 kg sheep loses ~ 1,600 Kcal as HP
~ 1.2 kg/d of hay (medium quality, GE=5,300
Kcal) needed to cover this loss
“Maintenance requirement”

Energy requirements

Of this GE of 5,300 Kcal
 ~2,400
Kcal lost in feces
 ~600 Kcal lost in urine & fermentation gases
 ~ 2,300 Kcal lost in HP

Another example: in a cow-calf system
~40% lost in feces
 ~10% lost in urine & gases
 ~ 45% lost in HP
 ~ 5% retained in the calf

Cont.

The purpose of nutrient utilization
 Maintenance
 Production
 Growth
(fat/muscle deposition)
 Milk production

The efficiency of ME utilization for maintenance

Fed at Maintenance + energy tissue mobilization ~ 67%
Cont. Milk production
Relatively tight range: 0.56 (poor diet) to 0.66
(best quality) efficiency
 Energy tissue (mobilization) utilization: ~ 0.84
Efficiency milk > meat
Quick removal of the product
High producer > low producer
genetic selection for more milk yield

Protein requirements

Crude protein (CP): N × 6.25
 All
N are presented in protein form
 All proteins contain 16% N


In reality; true protein & NPN
Digestible CP
 Endogenous
N
 Proteins from intestine (e.g., enzymes)
Cont.

Rumen degradation of proteins can be determined:
 Solubility
 In
vitro
 In saco
 Whole animal exp.



Essential AA: His, Ile, Lue, Lys. Met, Phe, Thr, Trp, Val
Rumen degradable (RDP) and un-degradable (RUP
or UDP)
Metabolizable protein (MP)
Cont.

MP: digestible total AA from
 microbial
proteins
 Feed proteins escaping rumen degradation but
digested & absorbed in the small intestine

Degradability is determined:
 Fraction
A: soluble (or lost through the bag)
 Fraction B: potentially degradable (passage rate &
degradability rate)
 Fraction C: Undegradable N
Cont.
RDP = A + B [kd/(kd+kp)]
RUP=100-RDP
Where RDP, RUP, fractions A, B & C are % of CP
Kd & kp are %/hr
Degradation of NPN=0.949
Microbial CP(g/d) =130 × TDN intake (RDP intake>1.18 ×
MCP)
Microbial CP(g/d) =0.85 × TDN intake (RDP intake<1.18 ×
MCP)
Cont.
Endogenous N (g/d) = 1.9 × DMI (kg/d)
The efficiency with which MP is used for
Maintenance=0.67
 Pregnancy=0.33
 Milk synthesis=0.67



Efficiency of MCP to MP= 0.64
AA model: AA requirement, AA content, efficiency
 Met
& Lys
 2.4 & 7.2% of MP or 1:3 ratio
Feeding Dairy cows






A minimum of ~ 17% CF (changes relative to
production)
At least 5-6 feed items
No undesired odor/color/taste associated w/ feeds
Primiparous cows (1st lactation) : + 20%
maintenance energy (ME)
Multiparous cows (2nd lactation) : + 10%
maintenance energy (ME)
Multiparous cows (3rd lactation): mature
Heifers





b/w weaning & age at 1st calving (~24 month): 810 times BW gain
Physiologically, rumen performs near complete at 4
month old but not in terms of its capacity: ~ 12-14
month
~45% mature BW at 1st breeding
Last trimester: ~ 40% fetus BW gain
20% addition of energy on top (if 1st calving)
Feeding calves





Dip naval
~ 2 liters colostrum at birth
~ 2 liters within the next 12-24 h
Continue for 3 d
It works!!!! Passive immunity
~
65% of operations do so by bucket or bottle
Cont.

Sometimes, it is more beneficial to use milk replacer
 More
saving when higher milk price
Water at day 3
Cocccidiostat in milk replacer
Weaning- traditional

Day 4 to weaning:
 Milk
replacer (~13% DM) at 10% BW/d
 At least 20% CP & 15% fat
 Twice/d
 Calf starter (commercially available)
 Free choice
 16-20% CP
 Not much forage
Cont.




Wean ~ 5-6 wk: when eating 0.5-0.7 kg starter/d
for at least 3 consecutive d
Milk to 50% during 1st wk and totally in 2nd wk
Leave in individual pen/calf starter for 1-2 wk
before moving to group pen/grain mix
~ 37% wean at wk 8; ~9% at wk 7; ~ 18% at wk
6; ~ 28% wean after wk 8
Calf starter intake and growth
(Eastridge and Weiss; 2005)
Age, day
Intake, lb/d
Age, day
BW, lb
7
0.25
3
95
14
0.35
28
127
21
0.7
36
148
28
1.2
57
170
35
1.9
72
195
42
3
86
230
49
3.5
96
265
Weaning- accelerated growth

At day 4, milk replacer
 14-17%
DM (more solids)
 26-28% CP (more protein); same fat content
~
2-2.2 liters twice/d for wk 1
 2.7-3.6 liters twice/d for wk 2 to wk 4-5
 2.7-3.6 liters once/d for 1 wk at weaning

At day 4, calf starter
 20-22%
CP (more protein)
 Intake is ~ half vs. traditional weaning
Cont.



Wean at 6-7 wk; when eating ~ 1 kg starter/d for
3 consecutive d
Continue high quality calf starter to 10-12 wk age
Offer forage when eating 2.2 to 2.7 kg starter/d
Comparison between Accelerated vs. Traditional
Advantages




Shorter time to
breeding (20-30 d sooner)
Increased gain
efficiency
Increased milk yield ??
Health & immune
system ???
Disadvantages




Increased feed costs
More loose feces
Delayed rumen
development
Intensive management
Growing heifers


To give birth ~ 23-24 months old
Should reach certain BW (+ certain height)
 Example:
8 mo
~500 to 575 lb (~ 43 in)
10 mo
~600 to 700 lb (~ 45 in)
12 mo
~700 to 780 lb (~ 47 in)
14 mo
~780 to 900 lb ( ~ 49 in)
Jersey: 14 mo
525 to 575 lb (~44 in))
Goal: (Holstein) ADG of ~1.7 lb/d; 1.2”/mo wither height
(Jersey) ADG of~ 1.3 lb/d; 1.1”/mo wither height
Ideal BCS & its relationship with milk yield
Age, month
Ideal BCS
3
2.2
6
2.3
9
2.4
12
2.8
15
3.0
18
3.2
21
3.4
24
3.5
The relationship of BCS at first calving
& 90-d milk yield (Waltner et al., 1993)
Dry matter intake of growing heifers
Age, month
Holstein
Jersey
BW, lb
DMI, lb/d
BW, lb
DMI, lb/d
3
250
7
165
4.6
5
350
9
240
6.6
7
450
11.3
320
8.3
9
550
13.4
400
10.6
11
650
15.4
480
12.1
13
750
17.5
560
13.7
Nutrient requirements (DM basis)
3-4 mo old
5-7 mo old
8 to
pregnant
Pregnant to
60 d pre-
CP, %
18%
14.5-15
13-14
13-14
ME, Mcal/lb
1.25
1.1
1.1
1.0
TDN, %
73
68
64-65
62-65
NDF, % max
22
44
Ca, %
0.9
0.75
0.7
0.65
P, %
0.45
0.35
0.3
0.25
Dry matter intake of pregnant heifers
Age, month
Holstein
Jersey
BW, lb
DMI, lb/d
BW, lb
DMI, lb/d
15
850
20.9
620
16
17
950
22.6
680
16.9
19
1030
24
740
17.7
21
1150
25.5
820
18.3
23-24
1300
22
920
15.1
Close up- pregnant heifers




Need more protein vs. mature cows (15-16 vs. 1214% CP)
First calving: + 20% energy
Second calving: + 10% energy
Feeding anionic salts: NOT recommended for
heifers
Lactating cows

Reduced DMI during early lactation
 Energy
tissue mobilization
 Possibility of protein mobilization



1.35-1.75% of BW= forage intake: rest from
concentrates
Not always feasible for high producers/early
lactation
2-3% of DMI: minerals/vitamins
Cont.

Concentrate intake:
 Milk
yield
 Milk composition (especially milk fat)
 Forage intake

Try to keep below 55-60%
 pH
 Forage
fermentation
 Acidosis
Cont.

Phase I (wk 0-10):
 increase
in DMI is lagging behind increase in milk yield
 Negative energy (and some proteins + minerals) balance
 Maintain 24-27% NDF
 High quality protein (UDP)
 Watch DCAD
 Promote feed intake
Cont.

Phase II (wk 10-20):
 Increased
DMI relative to milk yield
 Highest dry matter in milk
 Promote extension of this period
Cont.

Phase III (wk 20-44):
 Increased
DMI beyond milk yield
 Highest dry matter intake
 Watch for high BCS (BW gain)
 Replenishing used up stored nutrients
 Adjust concentrate
Cont.

Phase IV (wk 44-next parturition):
 No
milk yield
 Gradual decrease in dry matter intake
 Last 2-3 weeks: ~30% reduction in DMI
 Mammary gland involution
 Mostly forages; inexpensive
 Set up a close-up ration (3-4 wk before parturition)
 Close up: preparatory; b/w dry ration & lactating ration to
help feed intake, rumen performance, nutrient intake
General
For lactating cows:
 ~ 15-18% protein
 60-70% TDN
 NEL=1.4 to 1.8 Mcal/kg ration DM
 Inert fat (rumen-protected fat) for high producing cows
after wk 9-10
 Forage (effective NDF): rumen fermentation; milk fat
 Increase nutrient density of the concentrate not its
consumption
 Mineral blocks
Examples

Controlled (cross) feeding
 Amount
of concentrate
amount of milk yield
 ~2-3 kg concentrate (medium density) for 1 kg milk
 Rest: forage
 Old method; worked when cows produced ≤ 25 kg/d
If producing ≤ 25 kg/d, ~ 40% forages
If producing ~40 kg/d, ~ 16 kg/d typical concentrate;
DMI for this cow ~ 17 kg/d …!???!?
Cont.

Early lactation: much need for concentrate
 Not
enough forages
 Milk fat; poor rumen fermentation; acidosis
 Fatty liver-ketosis

Mid/Late lactation: possibility of over-conditioning
Cont.

Total mixed ration (TMR; complete diet)
 Everything
mixed
 Can’t choose what item(s) to eat and what to refuse
 Only how much to eat
 Similar ration for cows in a group
 Better to group cows (3-4 groups)
 More capital investment (mixer/feeder)
 Not so palatable feedstuff also in the mix
 More stable milk fat (less fluctuation)
Cont.
 More
stable rumen pH/fermentation
 Quality of the concentrate type feeds (no more
amount..!!!) it is all mixed
 Less laborious
 Works much better If a good reproductive
management in place (synchronized calving; easier
grouping)
 Difficult to group solely on milk yield
 Move cows based on yield/physiological stage
Rumen pH
6.5
pH
TMR
a. Feeding low
concentrate
6.0
5.5
Cellulose degradation
ceases
b. Feeding high
concentrate
6.5
pH
6.0
5.5
TMR
Cellulose
degradation ceases
Cont.

Flat rate feeding
 Fixed
amount of concentrate; variable forage (mostly
ad libitum)
 A simple method to execute
 Relies on stored energy tissue (body fat) especially
during early lactation
 During entire early lactation; high risk for lower-thanneeded concentrate (nutrient dens items)
 During phase III, high risk for more-than-needed
concentrate: over-conditioning
Cont.
 Nutrient
composition more important than amount fed
 Early lactation: increase nutrient density of concentrate
 High quality protein sources (UDP); protected fat
 Late lactation: reduce nutrient density of concentrate
Cont.

Mechanical feeder (distributor)
 Feed
individual cow based on milk yield
 Totally controlled on an individual basis
 High quality forage ad libitum
 Boss cows; too much concentrates; over-conditioning
 Low fat milk
Feeding sheep

General
 Adaptable
to relatively harsh condition
 Lower maintenance requirements
 Good fiber digestibility
 Diverse products (not seasonal)
 Great pasture-eater
 Faster investment turn-around (if fattening)
 DMI = 3.0-4.5% of BW
Cont.



Greater energy requirement when lactating (high
fat milk)
Flushing: intensive nutrition program to
promote/support twining
Transition period; 3-4 weeks pre- through
postpartum
 Would
help reducing BW losses, MG development &
milk yield if good quality proteins (RUP) are used
 Always consider Vitamin E and Selenium
Lamb operations





Programmed weaning (6-10 wk)
Takes ~ 100 days to 12 months
100-500 g/d ADG
Milk replacers
Creep feeding
Cont.
1) Early weaning/intensive fattening







~ 5-6 weeks on milk
~100 days
Creep feeding
2-3 weeks old; start ad libitum starter/high quality
alfalfa/ grains
Goal should be a FCR of > 3
60-80% concentrate: 20-40% forages
Flushing
Cont.
2. Early weaning/moderate fattening
 Applied when pasture and/or crop byproducts
available
 Same procedures for weaning/milk replacer
 Lower density grains/protein supplements
 Less expensive rations
 Longer time: 5-6 months
 Tubers; pulps; inexpensive by products; NPN
Cont.
3) Late weaning
Max BW
Takes 9-12 months
Pasture-based
Last few weeks on concentrates (feedlot) using good
quality proteins (RUP)
 inexpensive rations



