taking the inside-out approach to growing calves · taking the inside-out approach to growing...
TRANSCRIPT
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Taking the inside-out approach to growing calves
Noah Litherland, PhD
Dairy Youngstock Technical Specialist
Grow calves from the inside out?
To develop the GI tract and digestive processes and protect tissues for efficient
calf growth.
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Why grow calves from the inside-out?
1. Start strong-Successfully navigate through the first 10 days of the nursery phase
2. Finish strong-Successful weaning and transition into grower phase
Vita Plus Calf Approach
• Driven to understand calf biology• Guided by mom
• Low drama and practical approach
• Positive associative effects of nutrition and mgmt.
• Synchronizing feed chemistry with calf biology
• DMI is king and digestibility is queen
Digested Nutrients
Maintenance Growth
Nutrient Intake
Metabolizable Nutrients
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How do we measure success?• High rate of growth (> 1.8 lb./day)
• Consistent growth (R2 > 0.85).
• Understand and control cost of gain (< $1.30/lb. gain)
• Heifers calving at 80% of mature body weight and milking at least 80% of mature cows. -For every 5% increase in body weight (1125-1200) at calving, there is a 4 lb. increase in peak milk yield.
y = 2.0119x + 70.687R² = 0.9217
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0 10 20 30 40 50 60 70 80 90 100
Cal
f W
eigh
t, lb
Calf age, days
Balanced Parts of Calf Nutrition• Milk
• Dry matter intake as a % of BW• Milk volume• % solids• Osmolality• Macronutrients (protein, lactose, fat) • Ash (sodium)• Bacteria• Micronutrients (A, D, E, Zn)
• Starter• Intake• Starch• Fiber
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Balanced Sum of Parts• Dry matter intake
• amount, % of BW, timing, feeding behavior
• Protein• Amount, AA profile
• Energy• Amount relative to protein
• Fiber• Microbial diversity and mass, GI tract maturation, rumination
• Digestibility
• Rate of passage
What’s up with weird calf manure?
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Why is day 10 such an awkward age?
There’s a lot going on…• Maternal (colostral) immunity is waning.
• Calf’s own immune system is coming on-line.• Are these bacteria my friends?
• Not sure… let’s play it safe and crank up immune function
• Inflamation
• Happens to coincide with timing of pathogens reaching a critical mass to overwhelm gut barrier function and cause clinical signs of illness.
• Let’s face it….we still have quite a bit to learn about feeding and managing calves
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Normal Milk Digestion
• pH drop
• Start digestive processes
• Slowly meter digesta
• Digestion/absorption
• Normal rate of passage
• Low inflammation
• Gut barrier function
• Water absorption
• Diverse bacteria
• Positive immune sensing
• No inflammation
• pH increased
• Normal manure DM
• Once daily BM
• Total tract digestion > 90%
AbomasumSmall intestine
Large intestine
Fecal Output
Abnormal Milk Digestion
• More alkaline pH
• Fast digestapassage
AbomasumSmall intestine
Large intestine
Fecal Output
• Reversal of water flow (osmolality)
• Increased rate of passage
• Decreased digestion
• Decreased pH
• Water flow in
• pH decreased
• Aciduric bacteria predominate
• Inflammation
• Decreased manure DM
• Multiple BM
• Total tract digestion decreased
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How much milk to feed discussion (argument)
Usually goes something like this….1. Do you love your calves?
2. Milk is good, right?
3. Then if you love your calves and milk is good then you should feed more milk, right?
Evaluation of milk intake expressed as a percent of birth body weight
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Percent calves in RED (over/under-fed as a % of birth BW)
4 qt./day 6 qt./day 8 qt./day
Under-fed(<1.1% of BW)
10.6 0 0
Over-fed(>2.3% of BW)
0 10.3 69.8
This is not normal….
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Tremendous variation in calf ADG. This is likely due to variation in calf birth weight and response to the milk feeding amount and calf health.
Calf ADG sorted from high to low. This data helps visualize the opportunity for increased ADG
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Birth weight, lb.
4 liters (1.12 lb/d)
6 liters(1.68 lb/d)
8 liters(2.24 lb/d)
56 d weight, lb.
ADG, lb/d
# Calves
Intake, % of entry BW81 1.4 2.1 2.8 144 1.12 500
88 1.3 1.9 2.6 168 1.40 500
91 1.2 1.8 2.5 184 1.62 500
98 1.1 1.7 2.3 209 1.88 424
Evaluation of milk solids intake, % of birth BW
Meal Size and Frequency Alters Abomasal Function• Acidic environment provides a barrier to prevent some bacteria from
colonizing the intestinal tract.
• Abomasal pH >5, the survival rate of potentially pathogenic bacteria such as E coli and Salmonella species increases. • Colonization of the small intestine and development of diarrhea in calves is
more likely (Sen et al., 2006).
Feeding Frequency Avg. Abomasal pH
2X 3.44
3X 3.69
4X 3.64
8X 3.67
Ahmed et al., 2002
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Ab
om
asal
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Time relative to meal, hours
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Literature review- Excessive lactose feeding• Lactose is a natural laxative.
• Undigested lactose causes an osmotic pull of water from blood into the intestine.
• Rate of passage through the GI tract speeds up!!!!
• Lactose reaches the lower portion of the small intestine and the large intestine where it is fermented or passed out in feces.
• Shift in intestinal microbial ecology from a diverse population to a narrow population of bacteria tolerant of low pH (acidoduric bacteria).
Perhaps this shift in pH is one of the factors causing the loss of hair on the rump, tail, and backs of legs of calves with severe scours.
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Milk lactose dry matter changes considerably during the first week of lactation
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Lact
ose
, % D
M
Lactation, days
Milk lactose intake (g/day) when feeding 4, 6, or 8 quarts of milk
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Lact
ose
inta
ke, g
ram
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ay
Lactation days
4 qt/d 6 qt/d 8 qt/d
100 grams
100 grams
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Milk Lactose Intake
Tipping point for lactose intake:> 300 grams of lactose/day or >0.75% of BW
lactose intake
What is osmolality?????
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Milk/Blood Ocean water
Osm
ola
lity,
mO
sm/k
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Milk/Blood Ocean water
Osm
ola
lity,
mO
sm/k
gWhat is osmolality?????
Factors impacting milk/milk replacer osmolality effect on the calf
Milk Osmolality
Effect
% Milk solids Meal size
% Lactose
% Sodium (ash)
Calf hydration status
Meal frequencySolids intake as a % of BW
Milk hygiene
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Waste milk ≠ Saleable milk• Osmolality increases with bacteria count
• Presence of broad spectrum antibiotics
• Mastitis causes a decrease in lactose and increase in sodium
Milk replacer formula and solids alters osmolality
Floren et al., 2016
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How much fat?• Increased caloric density without exceeding volume or osmolality limits
Milk, % solids Milk DM Talon
Protein 3.1 25.8 25
Fat 3.7 30.8 25
Lactose 4.8 40.0 43.5
% Solids 12 100 100
Osmolality, mOsm/L 290 --- 368
We can feed about 160 g/d milk fat before starter intake averages < 2.0 lb./day (confounded with other factors)
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Ave
rage
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Fat intake, g/d
160 g/d or 5 quarts milk
280 g/d or 8 quarts milk
440 g/d or 12 quarts milk
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Plane of nutrition- first ten days
• Sensitive time period• Delicate immune system and GI tract
• Avoid over/under nutrition• Birth body weight
• Meal osmolality is critically important• Especially in stressed situations
• Provide adequate protein and energy in reasonably sized meals
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1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55
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ay
Calf age, days
Why are some farms able to feed 10+ quarts of milk with no apparent issues?• Exceptional maternity/colostrum
• Large calves
• Peak milk feeding amount after 3 weeks
• Clean milk (minimize osmolality issues)
• Smaller and more frequent meals
• Weaning age beyond 8 weeks of age
• Cost of gain is not a top priority
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Starter Intake = GI tract Maturation
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Star
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Age, days
Age, days Starter intake, lb.
21 0.5
28 1.0
35 2.0
49 4.5
56 5.5
Starter Intake Curve Shows Insight into daily variation in grain intake
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Impact of early starter grain intakeDays of age consuming 500 g/d starter intake
# of CalvesN = 267
Peak starter intake, lb/d
ADG at 49days, lb/d
ADG at 56 days, lb/d
< 21 days (16.9 d) 116 7.53 1.67 1.85
> 21 days (28.4 d) 151 6.78 1.54 1.67
Difference +0.74 +0.13 +0.18
Are calves that eat starter grain earlier better calves or does greater starter
intake make better calves?
Positive associative effects of fiber in nursery calfdiets
Castells et al., 2012
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Starch:Fiber1.5:1
683 Calves
y = 2.0119x + 70.687R² = 0.9217
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Growth of Holstein Dairy Heifers Milk (6 qts/calf/d),Calf Magnify (4 oz./calf/d), BSF Starter
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Weight, lb.
Weight Gain, lb.
ADG, lb./d
Hip Height, inches
Height gain, inches
Day 7 86.3 32.0
Day 60 198.9 112.6 1.88 37.1 5.1
Day 90 260.0 173.7 1.93 40.3 8.3
Growth of Holstein Dairy Heifers Milk (6 qts/calf/d),Calf Magnify (4 oz/calf/d), BSF Starter
Comparison of Pellet and BSF fed calves with targeted body weight at 40, 60, and 80 days of age
Age, Days
Target BW, lb.Holstein heifers
Pellet calves, lb.
Pellet Difference from target
BSFcalves, lb.
BSFDifference from target
40 150 126 (24) 130 (20)
60 190 162 (28) 175 (15)
80 225 195 (30) 210 (15)
% Resp. Trt 42.7 14.9
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Post-Weaning Growth Evaluation
ADG, lb/d # Calves % of Calves
Control Calves
Fail (< 1.8) 1.30 49 59.7
Pass (> 1.8) 2.14 33 39.3
BSF Calves
Fail (< 1.8) 1.41 11 13.6
Pass (> 1.8) 2.28 70 86.4
Milk: 4 qt/dStarter: Medium
Milk: 6 qt/dStarter: High
Milk: 8 qt/dStarter: Low
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Effects of milk feeding amount on nutrient intake and growth
Low 4 qt Medium 6 qt High 8 qtMilk solids, lb./calf/56 days 57 74 100Starter, lb./calf/56 days 87 113 60DMI, lb/calf/56 days 134 175 153ADG lb/d 1.39 1.87 1.83BW gain, lb 78 105 102Weight, 56 d 163 190 187CP intake, lb. 30 39 51Metabolizable Energy Intake, Mcal/d 268 348 339
Feed cost evaluation ($15/cwt milk and $0.28/lb starter)
90.29
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1.161.21
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$/l
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ain
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Rumen development• Feeding and rumination behavior
• Shift in metabolic hormones and enzyme
• Saliva production
• Shift in energy and protein supply
• Microbial diversity and density
• More consistent movement through the GI tract (pH stabilization)
• Suppression of enteric pathogens
• Consistent manure
Taking the inside-out approach to calf growth1. Are calves aggressive at milk feeding time?
2. Is calf manure firm and consistent?
3. Are calves ruminating?
4. Are calves achieving starter grain intake benchmarks?
5. Are calves achieving targeted growth rates?
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Calf Performance Goals for Consideration
• High rate of growth (> 1.8 lb./day).
• Consistent growth (R2 > 0.85).
• Triple birth BW by 90 days.
• Understand and control cost of gain (<$1.25/lb.)
• Heifers weighing 80% of mature body weight and milking at least 80% of mature cows.
Managing starter by milk program
• Low milk feeding (4 quarts/day)• High starter intake/high GI tract development• Risk of over-feeding starch and protein (increase fiber)• Favors early weaning (d 42)
• Moderate milk feeding (6 quarts/day)• Moderate starter intake/high GI tract development• Manage starter grain to encourage early intake and high peak
starter intake• Favors standard weaning (d 49)
• High milk feeding (>8 quarts/day)• Low starter intake/delayed GI tract development• Provide time for starter intake/feeding behavior to build• Favors delayed weaning (d 56)
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Design and implement a feeding regimen for your operation• Feeding approach that works for you and your calves
• Maximize use of on-farm resources
• All aspects of replacement heifer management
• Conventional, autofeeder, intensive feeding….
Lactose content by feeding program
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Lactose, % milk DM Lactose, % 25:25 DM Lactose, % 22:22 DM
Lactose, % 20:20 DM Lactose, % 26:10 DM
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Predicted DMI is greatest for Medium fed calvs
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DM
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Age, weeks
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eek
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347.7 339.3
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$/c
alf
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Protein, lb/lb
Energy, mcal/lb
Protein intake, lb/d
ME intake, Mcal/d
Protein allowable gain, lb/d
Energy allowable gain, lb/d
Milk replacer 25:25 0.25 2.30 0.40 3.7 1.3 1.1
Starter 18:5, 1.6 lb/d 0.18 1.47 0.69 6.1 2.0 2.2
Starter 18:5, 3.2 lb/d 0.18 1.47 0.98 8.4 2.7 3.1
Starter 18:5, 6.4 lb/d 0.18 1.47 1.6 9.4 4.2 4.5
What are the constraints to starter intake on your farm?• Is starter grain available by day 3?
• Is warm drinking water available shortly after milk feeding?
• Are calves battling health challenges that suppress growth and decrease feeding behavior?
• Does milk feeding rate exceed nutrient requirements and decrease feeding behavior delaying starter intake?
• Does starter feeding management constrain intake?
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Feed to minimize risk of creating variation in weaned heifer size• Birth weight
• Respiratory disease
• Variation in size within age
Summary of feeding recommendations
• Milk or milk replacer• Amount (1.4 - 1.8% of BW)
• Volume (4 - 7 qt/day)
• Solids (12 - 14%)
• Lactose (< 300 g/d or < 0.75% BW)
• Osmolality 290 – 420 mOsm/kg
• Fat: 140 – 200 g/d (MCFA)
• Protein: 40 lb/calf/56 days
• Lysine:methionine: 3:1
• Bacteria < 2 CFU/mL
• Starter grain• Protein 16 - 20%
• NDF: 10 - 22%
• Starch: 20 – 35%
• Starch: NDF: 1.5:1
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Positive associative effects-Examples
• Balancing starch and fiber
• Matching energy and protein allowable gain.
• Moderate lactose formulation
• Grow calves from the inside out
• Milk solids intake % of BW
• Hydration status
Evaluation of milk intake expressed as a percent of birth body weight• In the next slide, I calculated milk solids intake expressed as a % of
birth body weight for 4, 6, and 8 quarts of milk at 12% solids.
• Values are highlighted using the following color coding:• Green- Safe zone
• Solids intake between 1.3 and 2.3% of body weight
• Yellow- Caution zone• Solids intake may be too low/high depending on environment.
• Red- Not advised• Solids intake are too low/too high for optimal growth and digestion.
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Milk components-first 60 days of lactation
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Milk
so
lids,
%
Lactation, days
Protein, % Fat, % Lactose, % Ash, %
Waste milk analysis-heifer grower
Moore et al., 2009
Sample Milk solids, % pH SCC/mL
1 12.9 6.0 2,320,000
2 12.9 6.3 3,510,000
3 12.9 6.1 3,744,000
4 11.2 5.6 9,999,999
5 11.8 6.6 3,042,000
6 10.7 5.5 9,999,999
7 12.5 6.4 1,120,000
8 5.1 5.5 2,800,000
9 10.1 6.4 3,540,000
10 6.7 4.7 1,584,000
11 13.4 6.4 1,890,000
12 12.9 6.3 1,584,000
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Building and developing the rumen
• Microbial ecology
• Musculature
• Absorptive surface area
• pH balance (absorption and buffering)
• Rate of passage
Calf rumen function• Main rumen bacteria enzymatic activities (fibrolytic, amylolytic, proteolytic, and ureolytic) observed as early as day 4.
(Sahoo et al., 2005).
• Rey et al., 2012. France.
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Calf rumen microbial populations are ready to work (use starter) by about 2 weeks of age☺
A gallon of whole milk fails to meet the calf’s vitamin requirement
MineralNRC, 2001
Requirement, IUMilk, IU % of NRC supplied
Vitamin A, IU 5,218 5216 100
Vitamin E, IU 23 3.6 16
Vitamin D3, IU 272 139 51
Thiamin, mg 2.9 1.6 54
Niacin, mg 4.5 4 88
Pyridoxine, mg 2.9 1.6 54
B12, mcg 31.8 17.2 54
Folic Acid, mg 0.23 0.2 87
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Nutrient supply
Protein, lb/lb
Energy, mcal/lb
Protein intake, lb/d
ME intake, Mcal/d
Protein allowable gain, lb/d
Energy allowable gain, lb/d
Milk 25:30 0.25 2.44 0.40 3.9 1.3 1.6
Milk replacer 25:25 0.25 2.30 0.40 3.7 1.3 1.1
Milk replacer 20:20 0.20 2.09 0.32 3.3 0.9 0.9
Starter 18:5, 1.6 lb/d 0.18 1.47 0.29 2.4 0.4 0.0
Starter 18:5, 3.2 lb/d 0.18 1.47 0.58 4.7 1.2 1.2
Starter 18:5, 6.4 lb/d 0.18 1.47 1.15 9.4 2.7 2.8
Effect of milk replacer program on calf performance and digestion of nutrients in dairy calves to 4 months of age
Low Medium High P-value
Milk replacer intake, lb./d (total lb.) 1.01 (58.6) 1.67 (93.4) 1.92 (107.3)
Starter intake, lb./d 2.1a 1.4b 1.0c < 0.05
56 d weight, lb. 187.6 185.6 191.0 NS
ADG, lb./d 1.54 1.58 1.69 NS
Grams of ADG/Mcal. of ME intake 132 129 131 NS
Grams of ADG/g of CP intake 2.17 2.12 2.15 NS
Grams of ADG/gram of fat intake 5.61 4.18 3.97 NS
Hill et al., 2016Milk replacer: 28:20, 14% solidsStarter: 18% CP, 39% starch, 15% NDF Grower: Starter + hay (9% CP, 64% NDF)
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Calf Plumbing
• Key areas of opportunity• Milk should not be in the rumen
• Regulating abomasal pH and emptying rate
• Controlling inflammation
• Large intestine health and microbial diversity
Implications of decreased nutrient digestibility at weaning• ↑ passage of undigested solids
• Increased osmolality of undigested solids causes additional increase in passage rate
• Altered microbial ecology• Flushing of normal microflora
• Alteration in intestinal pH
• Inflammation and dehydration
• Hindgut acidosis
• ↓ in feed efficiency and growth
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Nursery program did impact gut function well into the grower phase
Digestibility, % Low Medium High P-value
Week 11
DM 72.6 74.0 70.0 0.08
NDF 37.7 33.5 25.1 0.01
CP 72.2 78.6 72.9 0.75
Week 16
DM 83.0 82.4 81.6 0.20
NDF 66.7 65.4 65.1 0.07
CP 84.7 83.6 85.9 0.02
Colostrum status impacts lactose digestion
• Nutrients and insulin in colostrum stimulate intestinal development and functionality.• Hormonal signals (insulin, IGF-1, GH)
• Glucose absorption
• Substrate for gluconeogenesis• Colostrum deprived calves are often hypoglycemic.
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Milk Feeding Errors-osmolality
• Feeding too high intake as a % of body weight
• Inconsistent mixing/delivery.
• Excessive/inconsistent additives.
• Milk hygiene issues • Equipment sanitation, pasteurizing, cooling, storage, transport…
• Feeding milk from cows with active mastitis infections.
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Loss of gut barrier function
Total tract nutrient digestibility of calves supplemented with forages
Castells et al., 2012
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Effects of milk feeding amount on nutrient intake and growth
Low 4 qt Medium 6 qt High 8 qt
ADG lb/d 1.39 1.87 1.83
BW gain, lb 78 105 102
Weight, 56 d 163 190 187
DMI, lb. 134 175 153
CP intake, lb. 29.9 38.9 36.0
Milk solids, lb. 57.2 74.3 100.4
Starter, lb. 87.1 113.3 60.5
Key questions- Calf growth basics
• What makes calves hungry?
• What is a calf’s work?
• When do calves grow the fastest?
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Why balance calf starter starch and fiber
• Feeding calves excessive starch/deficient fiber• Reduce ruminal pH (Beharak et al., 1998)• Decrease rumen motility (Clarke and Reid, 1974)• Cause hyperkeratinization and clumping of ruminal papillae (Bull et al., 1965)• Decrease ability of the rumen mucosa to absorb nutrients (Hinders and Owen, 1965)
especially if the feed is finely ground (Greenwood et al., 1997)
• Feeding balanced starch and fiber (20-25% NDF; 25-32% starch)• Forages stimulate the muscular layer of the rumen (Tamate et al., 1962)• Promote rumination (Hodgson, 1971; Philips, 2004)• Maintain the integrity and healthiness of the rumen wall (Haskins et al., 1969; Suarez
et al., 2007) • Decrease behavioral problems (Philips, 2001)
ROI in heifer growth• Assumptions:
• Heifers are calving on time 22 to 24 mo
• Heifers are well developed (not over-conditioned)
• For every 5% increase in BW at calving (1125 to 1200 lb.):• DMI increases 2.3 lb/day
• CP intake increase of 0.4 lb/d and NEL intake increase of 1.7 Mcal/d
• 4.2 lb/d increase in milk yield.
• +1,296 lb 305 milk.
• $194 increase in gross milk revenue
6/25/2018
45
Fat Intake, g/d for varying milk feeding rates
% fat in milk solids
Milk, quarts Milk Solids, lb. 20 25 31
4 1.0 91 113 140
6 1.5 136 172 213
8 2.0 181 227 281
10 2.5 227 286 354
A gallon of whole milk fails to meet the calf’s trace mineral and vitamin requirements
MicronutrientNRC, 2001
Requirement, mgMilk, mg % of NRC supplied
Zinc 18.1 12.0 66.0
Vitamin A, IU 5,218 5216 100
Vitamin E, IU 23 3.6 16
Vitamin D3, IU 272 139 51
Thiamin, mg 2.9 1.6 54