j anim sci 1970 hoffman 967 72
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8/12/2019 j Anim Sci 1970 Hoffman 967 72
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M. P. Hoffman and H. L. SelfYearling Steers
Shelter and Feedlot Surface effects on Performance of
1970, 31:967-972.J ANIM SCI
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SHE L T E R AND F E E DL OT SUR FAC E E FFE C T S ON
PER FO RMA NC E OF YEA RLIN G STEERS 1 2
M. P. HOFFMAN AND H. L. SELF a
Iow a S ta t e U n iversi t y A m es
WO important problems in Corn Belt
Feedlots are mud and temperature fluctua-
tions. The extent to which either or both can
modify the economic returns to cattle feeders
is not known. A project to determine the ef-
fects of overhead shelter and feedlot surface
was initiated in northwestern Iowa in the fall
of 1961. The three main criteria for evaluat-
ing effects were rate of gain, daily feed con-
sumpt ion and feed efficiency (kilograms of
feed per kilogram of live weight gain).
Materia ls and Methods
Twelve trials were conducted at the Allee
Experimental Farm, located at Newell near
the center of the northwestern quarter of
Iowa. The general pattern was to conduct the
winter season trials during the months of
November through April and the summer sea-
son trials during the months of May through
September. Except for the summer of 1963
and the winter of 1963 to 1964, two trials
were conducted each year.
Each of six lots, 10.7 m wide and 30.5 m
long, was oriented north and south, with a
surface gradient of 4 slope to the south.
A 3.6-m-wide service drive was provided
between each pair of lots (lots 1 and 2
equaling one pair, etc.). Each lot was en-
closed on three sides with five 0.95-cm
stranded cables on wood posts spaced ap-
proximately 2.7 m apart. Automatic waterers
were located so that each lot had access to
only one water bowl. Each lot contained a
self-feeder located near the service drive and
across the lot from the automatic waterers.
The south end of a barn, from which the
hay mow had been removed, provided shelter
with a dirt floor for lots 1, 2 and 3. The under-
roof area for each of the three sheltered
Iots was approximately 9.I4 m sq (83.6 m2).
1Journal Paper No. J-6495 of the Iowa Agriculture and
Home Economics Experimen t Station Ames Iowa. Project No.
1503.
Supported in part by funds suppIied by the Iowa Ready
Mixed Concrete Association.
a The authors wish to acknowledge the assi stance of D. F .
Cox in the statistical analysis; D. O. Hull F. W. Roth and
V. M. Meyer in the design and construction of the facilit ies
and N. Gay and C. E. Summers in the conduct of the experi-
ment.
Lots 4, 5 and 6 had only a board windbreak
2.13 m high across the north end of the lot.
Lots 3 and 4 were paved with concrete,
and lots 2 and 5 had an all dirt surface except
for a 3-m-wide concrete pavement across the
north end of each lot. Lots 1 and 6 had con-
crete only around the self-feeders and the
waterers in addition to the 3-m-wide concrete
pavement across the north end. Bedding was
not used in any of the lots at any time. The
surface space allowed per steer was sufficient
to avoid problems with excess manure ac-
cumulations except during wet weather. The
outside lot space was scraped as frequently
as necessary to prevent manure accumulating
to a depth of more than 5 to 8 centimeters.
The schedule varied depending upon type of
surface and moisture conditions. The area in-
side the shelter was cleaned according to need
and as weather and moisture conditions per-
mitted, usually only once but occasionally
twice during each trial.
The number of steers per lot per trial ranged
from 18 to 22, resulting in an average of
16.2 m 2 outside area per steer. An additional
4.2 m 2 of area under shelter was provided per
steer in lots 1, 2 and 3.
Temperature and precipitation data from
the U.S. Weather Bureau Station at Storm
Lake, approximtaely 19.3 km from Newell,
are presented in table 1.
Yearling cattle, predominantly of Hereford
and Angus breeding, were purchased and on
a group basis were allowed to regain their
original pay weight before being individually
identified, and before an average of two live
weights was obtained for a starting weight on
test. Weights were obtained at 28-day inter-
vals throughout the test period, with a few
exceptions due to weather or other factors.
The last of these periodic weights was taken on
the last day of the test and was used as the
final test weight to avoid excess handling im-
mediately prior to shipment for slaughter. At
the termination of the feedlot test period the
steers from this study were used in other
studies dealing with the effects of pre-
slaughter treatment on yield and carcass data
967
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968
HOFFMAN AND SELF
T A B L E 1. A V E R A G E M O N T H L Y P R E C I P I T A -
T I O N A N D T E M P E R A T U R E , S T O R M L A K E ,
I O W A 1 9 3 1 - 1 9 6 0 )
P r e c i p it a t io n A v g t e m p .
e m ) C )
J a n u a r y 1 . 88 - - 8 . 0
F e b r u a r y 2 . 62 - - 6 . 0
M a r c h 4 . 1 4 - - . 2
A p r i l 5 . 7 4 8 . 5
M a y 1 0 .1 3 1 5 .2
J u n e 1 1 .3 5 2 0 . 6
J u l y 9 . 4 7 2 3 . 5
A u g u s t 8 . 6 4 2 2 . 3
S e p t e m b e r 7 . 2 1 1 7 . 5
O c t o b e r 4 . 2 7 1 1 . 0
N o v e m b e r 3 . 3 8 1 . 2
D e c e m b e r 2 . 0 1 - - 5 . 2
which will be reported later. Starting and
final test weights and number of days on test
are shown in table 2.
The initial feed offered to the steers
a d
l i b i t u m
in self-feeders was a complete mixed
ration containing 65 ground corn cobs,
with the remainder made up of cracked corn
and a protein supplement fortified with vita-
mins and minerals to meet the National Re-
search Council (1963) requirements. The cob
level was lowered at the rate of 10 at ap-
proximately weekly intervals until the cattle
were on the ration they were to receive
throughout the remainder of the test. The
cob level did no t exceed 27 after the adapta-
tion period. The cattle were fed
a d l i b i t u m
at
all times from self-feeders.
All lots within each test were fed the same
number of days until visual appraisal indi-
cated that approximately 80~ of the cattle
T A B L E 2. A V E R A G E I N I T I A L A N D F I N A L
W E I G H T S A N D N U M B E R O F D A Y S O N T E S T
A v e r a g e A v e r a g e
i n i ti a l f i n al N u m b e r
S e a s o n w e i g h t w e i g h t o f d a y s
a n d y e a r T r i a l k g ) k g ) o n t e s t
W i n t e r
1 9 6 1 - 1 9 6 2 I 3 3 7 4 8 1 1 1 5
1 9 6 2 - 1 9 6 3 I I I 3 0 9 4 7 5 1 2 1
1 9 6 4 - 1 9 6 5 V 3 0 9 4 6 2 15 4
1 9 6 5 - 1 9 6 6 V I I 2 7 4 4 6 0 1 63
1 9 6 6 - 1 9 6 7 I X 2 8 1 4 5 4 1 5 2
1 9 6 7 - 1 9 6 8 X I 2 5 6 4 2 4 1 3 1
S u m m e r
1 9 6 2 I I 3 1 8 5 0 0 1 4 1
1964 IV 367 522 139
1 9 6 5 V I 2 9 3 4 7 2 1 4 0
1 9 6 6 V I I I 3 0 7 4 8 8 1 41
1967 X 277 482 147
1 9 6 8 X I I 3 1 5 5 0 7 1 4 0
in all lots would produce U.S.D.A. Choice
grade carcasses. This procedure resulted in
a range of 115 to 163 days on test for indi-
vidual trials. The wide range in length of trial
was because of variation in starting condition
of the cattle from one test to another and
the wide extremes in weather during indi-
vidual trials. The only segment available uni-
formly from all tests on gain, feed consump-
tion and feed efficiency was the first four
28-day weigh periods (112 days). Althougoh
the cattle on some tests were fed consider-
ably longer, it was decided that data through
the first 112 days would provide a critical
evaluation of the factors under test. The ef-
fects of shelter were studied in all 12 trials,
and the effects of surface were studied in the
first five trials. A preliminary analysis of the
data in the first five trials suggested that lot
surface was not having a significant influence
on performance and was not included as a
variable in the later tests.
Least-squares procedures and analysis of
variance for unequal subclass numbers were
used in the analysis of the data. The t-test
was used to test for differences between the
pooled means of all trials for each treatment
effect within each season. The difference be-
tween the pooled means for shelter in summer
and the pooled means for no shelter in sum-
mer was compared with the difference between
these two pooled means in winter by use of
the t-test.
Results and Discussion
R a t e o f G a in
Cattle with access to shelter
gained faster than cattle without shelter in
all trials, but this difference was significant
on a within-trial basis in only one winter
trial (Trial V, table 3). Pooling the data by
season resulted in a significant effect of shelter
in the winter (1.32
v s
1.15 kg; P~.01).
Williams (1958, 1959) found that cattle in
Canada in winter with access to shelter inside
a straw shed or wind protection by a 3-m-
high board fence on the north end of the lot
gained more rapidly than did cattle without
protection. Givens
e t a l
(1967) did not find
any difference in rate of gain for sheltered
and nonsheltered cattle under California win-
ter conditions. Observations in the trials here
in Iowa suggest that the different results in
California and Canada were probably due to
differences in the length and intensity of winter
storms in the two areas. Although it was not
possible for weigh dates to coincide with ex-
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S H E L T E R , F E E D L O T S U R F A C E A N D S T E E R P E R F O R M A N C E
T A B L E 3 . E F F E C T O F S E A S O N A N D S H E L T E R O N A V E R A G E D A I L Y G A I N
9 6 9
W i n t e r
Season Season
a nd ye a r T r i a l S he l te r No she l te r a nd ye a r T r i a l
Summer
She lter No shelter
k g k g
W i n t e r S u m m e r
1961-1962 I 1.37 1.12 1962 II
1962-1963 II I 1.33 1.14 1964 IV
1964-1965 V 1.25 1.06 1965 V I
1965-1966 V II 1.30 1.21 1966 V II I
1966-1967 IX 1.32 1.13 1967 X
1967-1968 X I 1.32 1,23 1968 X II
Av erage 1.32 1,15 *
Difference 0.17
k g k g
1.47 1.36
1.16 1.05
1.36 1.31
1.34 1.26
1.46 1.41
1 3 8 1 3 5
1.36 1.29
0.07**
* P
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970 H O F F M A N A N D S E L F
TABLE 5. EFFECT OF SEASON AND SHELTER ON DAILY FEED CONSUMPTION
Winter Summer
Season Season
and year Trial Shelter No shelter and year Trial Shelter No shelter
kg kg kg kg
Winter Summer
1961-1962 I 13.23 13.25 1962 I I 12.24 11.92
1962-1963 I I I 14.20 14.20 1964 IV 11.42 11.40
1964-1965 V 11.67 11.77 1965 VI 11.77 1 1 2 2
1965-1966 VI I 11.26 10.99 1966 VI I I 11.22 11.14
1966-1967 IX 11.11 11.16 1967 X 11.40 11.21
1967-1968 X I 10.98 11.33 1968 X I I 12.10 12.18
Average 12.08 12.12 11.69 11.51
Difference 0.04 0.18
c a n t l y a f f e c t d a i l y f e ed c o n s u m p t i o n i n a n y
o f t h e i n d iv id u a l t r ia l s t a b l e 5 ) . P o o l i n g t h e
d a t a w i th in s e a s o n i n d i c a t e d e s s e n t i a l l y n o
d i f f e re n c e b e tw e e n t h e s h e l t e r a n d n o n s h e l t e r
g r o u p s in w in t e r i n d a i l y f ee d i n t a k e 1 2 .0 8
v s . 1 2 .1 2 k g ) . Th e c a t t l e i n t h e w in t e r n o n -
s h e l t e r g r o u p h a d t h e s a m e g e n e t i c p o t e n t i a l
f o r w e ig h t g a in s a s t h o s e i n t h e s h e l t e r g r o u p
b u t l im i t e d t h e m s e lv e s t o a d a i l y f e e d i n t a k e
a p p r o x i m a t e l y e q u a l t o t h a t o f t h e s h e l te r e d
g r o u p . C l e a r l y , s o m e f a c to r r e l a t i n g t o a p -
p e t i t e o r t o t a l d i g e s t i v e - t r a c t c a p a c i t y w a s
o p e r a t i n g t o e f f e c t i v e ly e s t a b l i s h a n u p p e r
l im i t o n f e e d i n t a k e i n t h e n o n s h e l t e r e d c a t -
t le , d e s p i t e t h e i r o b v io u s n e e d f o r g r e a t e r
d a i l y e n e r g y i n t a k e . T h u s i t i s a p p a r e n t t h a t
c a t t l e h a v e a n u p p e r l i m i t o f c a p a c i t y f o r f e e d
in t a k e r e g a r d l e s s o f t h e i r r e q u i r e m e n t f o r a d -
d i t i o n a l n u t r i e n t s . I n g a l l s a n d S c a le 1 9 6 7 )
c o m p a r e d h e a t e d h o u s i n g w i t h o p e n - s h e d
h o u s i n g d u r in g t h e w i n t e r in C a n a d a a n d
f o u n d t h a t c a t t l e w i t h h e a t e d h o u s in g c o n -
s u m e d a b o u t 0 . 6 8 k g l e s s f e e d p e r d a y t h a n
c a t t l e i n o p e n - s h e d h o u s i n g w h e n b o t h g r o u p s
w e r e f e d f r e e c h o i c e a r a t i o n w i th a 9 :1
c o n c e n t r a t e - r o u g h a g e r a ti o . W i l l i a m s 1 9 5 9 ) ,
i n t e m p e r a t u r e s r a n g i n g b e t w e e n 7 C a n d
- - 3 7 C , o b s e r v e d a t e n d e n c y f o r f ee d i n t a k e
to d e c r e a s e a s t h e t e m p e r a tu r e d e c r e a s e d . Re -
s u l t s r e p o r t e d b y C a n a d i a n s M a c D o n a l d a n d
Be l l 1 9 5 8 ) s h o w e d t h a t f l u c tu a t i n g t e m -
p e r a t u r e s b e t w e e n - - 1 7 C a n d 7 C t e n d e d t o
in c r e a s e f e e d i n t a k e .
Th e p o o l e d m e a n s d id n o t d i f f e r s i g n i f i -
c a n t l y i n t h e s u m m e r , a l t h o u g h t h e r e w a s a
t e n d e n c y t o w a r d g r e a t e r d a i l y c o n s u m p t i o n
f o r s h e l t e r e d c a t t l e 1 1 .6 9 v s . 11 .51 kg) ,
w h i c h i s i n a g r e e m e n t w i t h t h e o b s e r v a t i o n
n o t e d e a r l i e r t h a t c a t t l e w i th s h e l t e r in s u m -
m e r g a in e d s i g n i f i c a n t l y f a s t e r t h a n c a t t l e
w i t h o u t s h e l t e r . R a g s d a l e
e t a l .
1 9 5 3 , 1 9 5 4 ) ,
i n M is s o u r i , n o t e d t h a t r e l a t i v e ly h ig h a n d
l o w h u m i d i t i es a t t e m p e r a t u r e s b e l o w 2 4 C
d id n o t a f f e c t f e e d i n t a k e o f l a c t a t i n g c o w s ;
h o w e v e r , u p o n i n c r e a s i n g t h e h u m i d i t y a t
t e m p e r a t u r e s a b o v e 2 4 C , f e e d i n t a k e w a s r e -
d u c e d . S im i l a r f i n d in g s w i th t e m p e r a t u r e s
a b o v e 2 4 C h a v e b e e n r e p o r t e d b y o t h e r w o r k -
e r s W a y m a n e t a l . 1 9 62 ; D a v i s a n d M e r i l a n ,
1 9 6 0 ; J o h n s o n , Ra g s d a l e a n d Y e c k , 1 9 6 0 ) .
F e e d c o n s u m p t io n w a s s i g n i f i c a n t l y r e l a t e d
t o t y p e o f s u r f a c e P ~ . 0 5 ) i n o n e w i n t e r
T r i a l V ) a n d in o n e s u m m e r T r i a l I V , t a -
b l e 6 ) . A n a ly s i s o f t h e p o o l e d d a t a f r o m
TABLE 6. EFFECT OF SEASON AND FEEDLOT SURFACE ON DAILY FEED CONSUMPTION
Winter Summer
Season Part Con- Season Part Con-
and year Trial Dirt concrete crete and year Trial Dirt concrete crete
kg kg kg kg kg kg
Winter Summer
1961-1962 I 13.11 13.28 13.33 1962 I I 12.10 11.97 12.17
1962-1963 I I I 14.20 14.20 14.20 1964 IV 11.40 11.34 11.50
1964-1965 V 11.48 11.91 11.77
Avera ge 12.93 13.13 13.10 11.75 11.66 11.84
* P
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S H E L T E R, F E E D L O T S U RF A CE A N D S T E E R P E RF O RM A N CE
TABLE 7. EFFECT OF SEASON AND SHELTER ON FEED EFFICIENCY
971
Winter
Season Season
and year Trial Shelter No shelter and year Trial
Summer
Shelter No shelter
kg kg
Winter Summer
1961-1962 I 4.41 ~ 5.36* 1962 II
1962-1963 III 4.84 5.67 1964 IV
1964-1965 V 4.26 5.02* 1965 VI
1965-1966 VII 3.84 4.05 1966 VIII
1966-1967 IX 3.77 4.38* 1967 X
1967-1968 XI 3.76 4.14 1968 XI I
Average 4.15 4.77**
Difference 0.62
kg kg
4.12 4.29*
4.48 4.95
3.93 3.95
3.82 4.01
3.53 3.55
3.95 4.04
3.97 4.13
0.16 *
a Ki:ograans of feed per kilogram of gain.
P < . 0 5 .
H P~.01.
trials within season revealed no significant
overall effects of feedlot surface on feed in-
take. Shelter and surface did not interact
signif icantly to affect feed i ntake.
F e e d E i ~ c i e n c y
Shelter lowered the feed
requirements per kilogram of gain in all 12
trials (table 7) and significantly so (P ~. 05 )
in winter trials I, V and IX and summer
trial II. Pooling the data by season indicated
that feed efficiency over all winter trials was
4.15 kg for the shelter groups and 4.77 kg
for nonshelter groups (P ~. 01 ). Williams
(1958, 1959) found in Canada that cattle
fed a 50% grain and 50% pelleted roughage
ration required less feed per unit of gain when
protection was afforded by either a straw shed
or a 3-m-high board fence on the north end
of the lot. Givens
e t a l
(1967) observed in
California that cattle with shelter in winter
were only slightly more efficient than cattle
without shelter.
Th e pooled d ata for feed efficiency in sum-
mer indicated that shelter reduced the feed
required per kilogram of gain (3.97
v s
4.13
kg), although the reduction was not statis-
tically significant. The spread between the
pooled mean differences (0.62 v s 0.16 kg) in
winter and summer was significant (P~.01),
indi cati ng tha t shelter had a greater effect
upon feed efficiency in winter than in summer.
None of the five trials in which surface
was considered showed any significant effect
upon feed efficiency (table 8). Pooling the
trials by season did not reveal a significant
effect of surface on feed efficiency, although
the cattle on dirt in winter and those on con-
crete in the summer tended to be more effi-
cient. Shelter and surface did not interact
significantly to influence feed efficiency.
Shelter had a pronounced effect upon cattle
performance in the feedlot. Type of surface
had little observable effect upon the economi-
cally important traits; however, observations
during the first five trials indicate that ap-
proximately 30% as much labor and ma-
chinery time was required to remove manure
from and to maintain the lot when it was
paved with concrete as was required to clean
and m aint ain a lot with a di rt surface. For
this reason alone, concrete pavi ng was a justifi -
able investment.
TABLE 8. EFFECT OF SEASON AND FEEDLOT SURFACE ON FEED EFFICIENCY
Winter Summer
Season Part Con- Season Part Con-
and year Trial Dirt concre te crete and year Trial Dirt concre te crete
kg kg kg kg kg kg
Winter Summer
1961-1962 I 4.56 ~ 5.02 5.09 1962 II 4.22 4.26 4.14
1962-1963 II I 5.43 5.30 5.03 1964 IV 4.80 4.76 4.59
1964-1965 V 4.42 4.66 4.84
Average 4.81 4.99 4.99 4.51 4.51 4.37
a Kilograms of feed per kilogram of gain.
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9 7 2
H O F F M A N A N D S E L F
S u m m a r y
S i x w i n t e r a n d s i x s u m m e r t r ia l s in v o l v i n g
1 ,4 1 5 y e a r l i n g s t e er s w e r e c o n d u c t e d t o s t u d y
t h e e f f ec t s o f s h e l te r a n d f e e d l o t s u r f a c e o n
r a t e o f g a in , f e e d c o n s u m p t i o n a n d f e e d ef fi -
c i e n c y .
S h e l t e r s i g n i f i c a n t l y in c r e a s e d r a t e o f g a i n
i n b o t h s u m m e r a n d w i n t e r , w i t h t h e g r e a t e r
e f f e c t o c c u r r i n g i n w i n t e r . S h e l t e r d i d n o t s i g -
n i f i c a n t l y a f f e ct f ee d c o n s u m p t i o n i n e i t h e r
w i n t e r o r s u m m e r , b u t d i d h a v e a s i g n i f i c a n t l y
b e n e f i c i a l e f f e c t o n f e e d e f f i c i e n c y i n w i n t e r .
T h e r e w a s o n l y a t r e n d t o w a r d i m p r o v i n g f e ed
e f f ic i e n c y w i t h s h e l t e r i n s u m m e r ; c o n s e -
q u e n t l y , s h e l t e r i m p r o v e d e f f ic i e n cy s ig n i f i -
c a n t l y m o r e i n w i n t e r t h a n i n s u m m e r . S u r -
f a c e d i d n o t s i g n i f i c a n t l y a f f e c t r a t e o f g a i n ,
f e e d i n t a k e o r f e e d e ff i ci e n cy , a l t h o u g h p a v -
i n g d i d g r e a t l y e x p e d i t e t h e r e m o v a l o f m a -
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N E W S N D N O T E S
8 3
m e n t a l , c ol le g e a n d u n i v e r s i t y c o m m i t t e e s , a n d
r e s e a r c h a n d e x t e n s i o n a ct i v it i es . N o t a l l o f
t h e s e a r e e s s e n t i a l a s f a c t o r s i n c o n s i d e r a t i o n
f o r t h e a w a r d ) .
f . E x t r a - c u r r i c u l a r a c t i v i ti e s b e y o n d r e g u l a r
t e a c h i n g d u t i e s .
g . H i s s e r v ic e t o a g r i c u l t u r e a n d r e l a t e d i n d u s -
t r i e s .
2 . M a t e r i a l t o b e s u p p l i e d b y t h e n o m i n a t o r :
a , S i x c o pi e s o f a b i o g r a p h y o f t h e n o m i n e e .
b . S i x c o p i e s e a c h o f l e t t e r s i n s u p p o r t o f t h e
n o m i n e e f r o m n o t l e s s t h a n f iv e n o r m o r e t h a n
t e n c u r r e n t o r f o r m e r s t u d e n t s .
P r o c e d u r e s t o b e u s e d b y t h e se l e c ti o n c o m m i t t e e s
w i l l f o l l o w t h o s e p u b l i s h e d i n t h e J . A n i m . S c i . 2 7
1 9 6 8 ) : 2 7 3 - 2 7 5 .
E R R A T A
J o u r n al o f A n i m a l S c i e n c e , V o l u m e 3 1 , N o . 5 , p a g e 9 6 7 , S h e l t e r an d
Fee d lo f Sur face E f fec ts on Per fo rm ance o f Ye ar l ing S tee r s . A l l o f the
va lues fo r feed e f fic iency in tab les 7 and 8 , and the accom pany ing tex t
( p a g e 9 7 1 ) a r e to o s m a l l b y a f a c t o r o f 2 . 2 .
J o u r n al o f A n i m a l S c i e n c e , V o l u m e 32 , N o . I , p a g e 1 4 8 , S t a b i l it y o f
D ie thy ls t ilbes tr o l and Its E f fec t on Per fo rm ance in Lam bs . A t the en
of the fi rs t pa r agr ap h , the las t pa r t o f the sen tence shou ld r ead co var i -
an t ana lys is show ed the reg ress ion coef f ic ients to be s igni f icant ly d i f fer -
e n t ( P < . O I } .