This document summarizes research on free walk housing systems in the Netherlands. Three key points: 1. Free walk housing can be economically viable if bedding costs are low and cow longevity increases due to better welfare and health. Intensive composting of bedding materials like wood chips can reduce nitrogen losses. 2. Animal welfare and health are improved in free walk systems compared to freestalls. Milk quality risks need attention, and ammonia emissions vary depending on bedding material and aeration. 3. Different bedding materials - like wood chips, compost, straw - impact the sustainability profile, with compost and wood chips providing good quality soil improver but needing management to control nitrogen release.

1. Development and sustainability of Free
Walk housing in the Netherlands
February 23 2017, Lille France
WUR: Paul Galama, H.J. van Dooren, W. Ouweltjes, H. de Boer
NIZO: Frank Driehuis

2. Animal welfare and
manure quality
Labour efficiency
Why Free Walk (Bedded Pack Barns)?

3. Why Bedded Pack Barns?
Lying area is also manure storage

4. Sustainability
Animal welfare & healthEconomics
Environment
Quality

5. Environment Manure quality
Compost and
Wooden chips
Input NPC
Emission
land
Emission
stable
Emission of NPC
N2
N20
NH3
CH4
Freestall
Bedded
Pack
Barn
export NPC

6. Experiments on 3 regional farms
Drainage with sandComposting: wooden chips an sawdust
Absorbing with peat ground and reed Cows in Green house with folie

7. Monitoring 10 commercial farms;
5 are composting wood chips
1. Blowing air 2. Blowing air
5. No aerating3. Suckling air 4. Suckling air

8. four using green waste compost
one cultivates straw
10 Straw
Farms 6 to 9
use compost

9. Composting ...
once a day mill the bedding
12 – 15 m2 per cow

10. Aerating system,
Blowing air

11. Aerating system,
Suckling air

12. Bedding material used on grassland and arable land

13. Roof from horticulture

16. Farm characteristics
1 2 3 4 5 6 7 8 9 10
Number of cows 60 130 50 105 75 55 185 80 15 65
M2 per cow 16 15 13 14 10 22 27 9 20 11
Bedding material W W W W W C C C C S
Aeration B B S S N
Milking system AMS AMS AMS AMS AMS AMS
Grazing No Yes Yes No No Yes No No No Yes
Bedding material
W = wood chips
C = Compost
S = Straw
Aeration system
B = blowing air
S = sucking air
N = no aeration

17. Sustainability
Animal welfare & health

18. Animal health (Mastitis), SCC (*1000 cells/ml)

19. Longevity

20. Animal welfare and health
Welfare Bedded pack vs freestall
Time required to lie +
Hygiene 0/+
Skin injuries ++
Legs and claws +
Natural behaviour +
Health
Udder health 0
Antibiotics usage 0
Longevity +?
Temperature sensor
No heat stress from
heat production bedding

21. Sustainability
Economics

22. Economic effect of lower culling rate

23. Economics bedded pack barns
Bedded pack barn vs freestall
Investment manure storage -
Investment roof ++
Total investment +
Yearly costs stable and bedding +
higher production per cow +
lower replacement --
Total yearly cost -

24. Sustainability
Quality

25. Risk of sporeforming bacteria for milk quality
(X)TAS =
(Extreme) Thermofilic Aerobe Sporenformers
XTAS can lead to spoilage problems
of commercially sterile dairy products
Route of (X)TAS
Compost
Wood
chips

26. XTAS in bedding materials (cfu / gram on log scale)
variation between samples
Together to the next level
0
2
4
6
8
10
12
14
16
1 2 3 4 5 6 7
Numberofsamples
XTAS-Class
Sawdust / straw
0
2
4
6
8
10
12
14
16
1 2 3 4 5 6 7
Aantalmonsters
XTAS -Class
Wood chips
0
1
2
3
4
5
6
7
8
1 2 3 4 5 6 7
Aantalmonsters
XTAS-Class
GFT-compost
Source: NIZO
Directive Dairy Industry: log 5

27. TAS in milk (Source NIZO)
0
200
400
600
800
1000
1200
1 2 3 4
TASinmilk(cfu/liter)
sawdust freestall wood compost straw

28. Sustainability
Environment

29. Contribution of bedding material to
net N input on the barn floor
WC = wood chips, GWC = Green Waste Compost

30. Range in N loss (% of total N-input)
30
19%
35%
40% 40%
44%
63%
0%
10%
20%
30%
40%
50%
60%
70%
1 WC 3 WC 4 WC 5 WC 8 GWC 9 GWC
Gaseous N loss (% of N excreted on the barn floor)
Barn code
WC = wood chips
GWC = green waste compost

31. Low N loss with active composting
31
‐30
‐20
‐10
0
10
20
30
40
50
60
70
2‐11‐13 12‐12‐13 21‐01‐14 2‐03‐14 11‐04‐14 21‐05‐14 30‐06‐14 9‐08‐14 18‐09‐14 28‐10‐14
N loss (% of N excreted on the barn floor)
Date
Active composting Passive composting

32. Intensive composting: strong relationship
between development of N loss and C/N ratio (1)
32
0
10
20
30
40
50
60
70
‐25
‐20
‐15
‐10
‐5
0
5
10
13‐11‐13 13‐12‐13 13‐01‐14 13‐02‐14 13‐03‐14 13‐04‐14 13‐05‐14 13‐06‐14 13‐07‐14
C/N ratio bedding
N loss (% of N excreted on the barn floor)
Date
N loss C/N ratio bedding

33. Overall sustainability
Sustainability
aspect
Criteria Wood chips
5 farms
Compost
4 farms
Straw
1 farm
Economics investment
Yearly costs
longevity
Cow Production, health
Welfare
Milk quality XTAS
Environment N losses stable Prohibited
N losses land
Ammonia emission stable 2 farms and
Dairy Campus
Nitrous oxide emission
Manure Quality Soil Improver
N mineralisation
better
attention needed
worse

34. Change of bedding
Use of compost is prohibited, now straw

35. Conclusions
 Free Walk housing can be profitable if bedding material is
not too expensive and cow replacement will be reduced
 “Intensive” composting can reduce the N-loss of the
bedding by incorperation of excreted N in bacterial biomass
 Ammonia emission in stable uncertain until end of 2017,
but emission in the field is lower
 “Composted wood chips / manure” is a good soil improver,
but N will release slowly
 (X)TAS bacteria is a point of attention

36. Points to continue
 Bedding material and management
● Alternative for Green Waste Compost
● Control composting process of wood chips
● Emission factor (kg NH3/cow/year)
 Synthetic floors
● Hygiëne floor / cow and milk quality
● Emission factor (kg NH3/cow/year)
 Sustainability of whole farming system
 Multiple use of building

37. Draining floor
Draining artificial floor
Feces
Urine

38. Seperating feces and urine on rubber floor
Feces
Urine

39. ...artificial floor...

40. “Cowgarden” and floor cleaning robot
Floor from ID Agro (Netherlands)
Robot from Betebe (Germany)

41. Artificial floor
to seperate feces and urine
robot picks up the feces

42. Dairy Campus facilities in Leeuwarden
Emission measuring unit
for case control research
6 units of 15 cows:
- 4 Cubicles
- 2 Free Walk

43. Meadow floor
...to reduce ammonia emission while improving cowmobility..

44. aerating
...to mix slurry and reduce ammonia emission...

45. Sustainability
Animal welfareEconomics
Environment
Quality

46. Free Walk
Holistic View
Animal welfareEconomics
Environment
Cow
Soil
NPC balance
Farm Manure
‘Compost’
Quality
Free Walk
Holistic View
Animal welfare
SocietySociety
Economics
Environment
Cow
Soil
NPC balance
Farm
Quality
Manure
‘Compost’
Crop
Bio-
diversity
Bio-
diversity
Soil fertility
Multiple use of building
ERANET-Susan project with
8 countries (2017-2020)

47. Thank you
More information: www.vrijloopstallen.nl
Paul.galama@wur.nl