This study measured cortisol concentrations in hair samples from beef cattle in Denmark to assess chronic stress. Hair was collected from 24 farms across the country and cortisol was extracted and analyzed. The results showed that hair cortisol: 1) varied geographically and between breeds, ages, and housing/management conditions; 2) was affected by factors like leg cleanliness and physiological state; and 3) while complex, may provide a measure of chronic stress in cattle. Further investigation of the identified factors is needed.

1. Survey
of
hair
cor.sol
concentra.ons
in
Danish
ca4le
Regitze
Charmac1,
Alberto
Prandi2,
Antonella
Comin2,
Marta
Mon9llo2,
Rupert
Bruckmaier3,
Josef
Gross3
and
Christopher
Knight1
1University
of
Copenhagen,
Denmark,
2University
of
Udine,
Italy
and
3University
of
Bern,
Switzerland
regitzecc@hotmail.com
Introduc9on
• Cor9sol
is
an
important
component
of
the
HPA
”stress”
axis
• Plasma
cor9sol
concentra9on
is
unreliable
due
to
sampling
stress
• Hair
cor9sol
concentra9on
(measured
properly)
reflects
an
integrated
value
of
cor9sol
that
has
accumulated
over
weeks
or
months
Objec9ves
• To
measure
hair
cor9sol
in
a
cross-­‐sec9on
of
beef
caTle
from
around
Denmark
• To
assess
the
usefulness
of
hair
cor9sol
as
a
measure
of
chronic
stress
Materials
and
Methods
• We
approached
232
beef
caTle
farmers
from
9
postcode
areas
around
Denmark
• Of
the
35
that
responded,
24
farms
were
visited
and
hair
samples
obtained
• Forelock
hair
was
taken
and
the
2cm
closest
to
the
skin
was
selected
for
analysis
• Hair
was
washed,
and
cor9sol
was
extracted
and
analysed
according
to
a
rigorous
protocol
• Data
(pg/g)
have
been
analysed
using
a
series
of
single
factor
ANOVARs
Results
• The
overall
mean
hair
cor9sol
concentra9on
was
2.69±0.07
pg/mg
• Hair
cor9sol
concentra9on:
• Varied
geographically
(Figure
1)
• Was
lower
in
older
animals
(Figure
2)
• Varied
amongst
breeds
(Figure
3)
• Was
affected
by
housing
condi9ons
(Figure
4)
• Varied
according
to
cow
comfort
(leg
cleanliness:
Figure
5)
• Was
affected
by
physiological
state
(Figure
6)
Conclusions
• The
date
are
complex
and
final
interpreta9on
will
require
care
• Nevertheless,
hair
cor9sol
may
be
of
value
in
assessing
chronic
stress
• A
number
of
factors
worthy
of
detailed
inves9ga9on
have
been
iden9fied
TGSSHLJCHD*XCAA
10
5
0
Breed
Cortisolpg/g
151050
10
5
0
Age
Cortisolpg/g
Figure
1.
Sample
area
Cor9sol,
pg/mg,
mean
±
SE
(n)
Figure
2.
Age
Cor9sol,
pg/mg,
individual
values
Figure
3.
Breed
Cor9sol,
pg/mg,
median,
quar9les
and
range
ILH LHO TS SF ILH ILHO
Housing type
0
1
2
3
4
5
6
Cortisolpg/g
LooseHoused
TieStalls
SlattedFloor
LooseHoused
Outdoor
Outdoor
P<0.01
Within FarmAcross Farms
(36) (40)
(204) (78) (16) (7)
P<0.001
Clean Average Dirty
Leg cleanliness
2.0
2,4
2,8
3.2
Cortisolpg/g
Outdoor
P<0.01
(64)
(104)
(137)
Young/Open Pregnant Lactating
Physiological state
2.0
2,4
2,8
3.2
Cortisolpg/g
Outdoor
P=0.01
(77)
(112)
(49)
Figure
4.
Housing
Cor9sol,
pg/mg,
mean
±
SE
(n)
Figure
5.
Comfort
Cor9sol,
pg/mg,
mean
±
SE
(n)
Figure
6.
Status
Cor9sol,
pg/mg,
mean
±
SE
(n)
Aberdeen
Angus,
Charolais,
Cross-­‐breds,
Dairy
breeds,
Dexter,
Hereford
Jutland
CaTle,
Limousin,
Scoish
Highland,
Simmental,
Tiroler
Grauvieh
(18)
(20)
(7)
(9)
(21)
(61)
(9)
(37)
(27)
(21)
(10)
Most
cows
were
loose
housed
Tie
stall
data
was
from
2
farms,
slaTed
floor
from
1
farm
only
Data
should
be
interpreted
accordingly
Within
farm
data
was
from
6
farms
Leg
cleanliness
has
been
interpreted
as
an
index
of
cow
comfort
(eg
Dairy
Co
”Scoring
Cleanliness”)