F E E D CONSUMPTION, RATE OF GAIN AND RATION
D I G E S T I B I L I T Y OF CAGED VERSUS
P E N N E D LAMBS 1
C. M. GRIEVE2 AND S. E. BEACOM
Research Branch, Canada Department of Agriculture,
Melfort, Saskatchewan, Canada
1 9 ~ x 3 4 in., plus an additional 1 2 ~ in.
for the feeder. Overhead water jugs connected by means of plastic hose to watering
few comparisons have been made, there is cups in each stall, provided clean water autosome evidence which suggests that data ob- matically. The other two lots were kept in
tained with sheep confined in cages or stalls a 16 x 20 ft. pen in which were built eight
may not be comparable to those obtained feeding stalls 21 x 3 0 in. not including an
additional 12 in. to accommodate the feeder.
with sheep confined in pens.
Except for Experiment I I all water was proChurch and Fox (1959) observed that
stall-fed lambs consumed less feed, gained vided by a 15 gal. trough in the middle of
the pen. Wood shavings were used as bedding.
less weight and had more variable gains than
All lambs were individually fed all they
group-fed or individually pen-fed lambs.
Lawrence and Troelsen (1961) reported that would consume twice daily, from 7:30 to 9:30
yearling wethers confined in digestion stalls a.m. and 3:00 to 5:00 p.m. In addition t h e y
consumed less feed daily and gained much had access to cobalt-iodized salt and a minmore slowly and less efficiently than did those eral mixture containing defluorinated calcium
kept in a pen and individually fed twice daily. phosphate and salt.
The lambs were weighed after 12 hours
This study was carried out to compare the
performance of growing-fattening lambs con- without feed and water on two consecutive
days at the beginning of each experiment and
fined in an eight unit metabolism battery
with that of lambs kept in a pen and indi- at the completion of the final experiment.
vidually fed in stalls twice daily. Two all- The weights on consecutive days were
roughage diets of widely different feeding averaged to obtain initial and final weights.
Digestion studies were conducted with each
value were compared in the growing period.
wether during the last 7 days of Experiment
Subsequently two finishing diets containing
I and I I I , and the last 5 days of Experiment
different forages were tested.
II. Canvas bags, with polyethylene bags inserted, and attached to the lambs by harnMaterials and M e t h o d s
esses, were used to collect feces from the
Sixteen Suffolk x Rambouillet wether lambs, penned wethers. Total feces collections from
averaging 26.2 kg. liveweight, were divided each wether were weighed daily and aliquots
into four weight groups. The four lambs comprising one-tenth of the feces stored at
in each weight group were then distributed
0 ~ C. At the end of each digestion period
at random to the four treatment lots.
the aliquots from each wether were ovenTwo lots of lambs were confined in metab- dried at 85 ~ C., composited and ground in a
olism cages for 81 consecutive days during
laboratory mill, and a sub-sample taken for
which three experiments were completed. The
analyses. Samples of feed and refused feed
metabolism unit, designed and constructed
at the Experimental Farm, Melfort, con- were collected daily and sub-samples were
prepared in the same manner as described
sisted of eight individual cages separated
by partial partitions which allowed close con- for feces.
Samples of feed, refused feed and feces were
tact between the lambs. Each stall measured
analysed for dry matter and crude protein
1 Contribution from the Animal Science Section, Research
by A.O.A.C. (1960) methods, and gross
Branch, Canada Department of Agriculture, Melfort, Sasenergy determined in a Parr oxygen bomb
katchewan, Canada.
2 Present address: Faculty of Agriculture, University of the
calorimeter.
West Indies, Trinidad.
628
I G E S T I O N and forage evaluation studies
D have frequently been conducted with
sheep confined in metabolism cages. Although
CAGED VERSUS P E N N E D LAMBS
The experiment was set up and analysed
as a split-plot, with "method of confinement"
as the "main plot" and "rations" as the
"subplot". Four replicates were included.
Method of confinement and replicate with 1
and 3 degrees of freedom respectively were
tested against error (a) with 3 d.f. while
ration and feeding method x ration, each
with one d.f. were tested against error (b)
with 6 d.f. Error mean squares are shown in
table 2.
629
for 28 days. Red clover hay (16.8% crude
protein) made up the roughage portion for
lambs previously fed alfalfa, and brome hay
(12% crude protein) was fed to lambs previously fed the slough hay.
Results
Access to water during the feeding periods
(Experiment II) appeared to have no effect
on rate of gain or feed consumption of the
lambs. Daily dry matter intake and weight
gains were 900 and 61 gin. respectively by
lambs with water, compared to 970 and 82 gin.
respectively by those without water during
the feeding periods. A comparison of means
by the t-test revealed no significant differences. Consequently, the feed consumption
and daily gain data of Experiment I and I1
were combined and presented for the 53-day
period (table 1).
Experiments I and H. There was little
difference between the performance of caged
and penned lambs (table 1). The intake of
dry matter per d a y and per unit of metabolic
weight and the average daily gains were
similar under both methods of confinement.
The relative intakes (actual intake as a proportion of 80 gin. of a standard forage per
kilogram of metabolic weight) and the Nutritive Value Indexes (relative intake of the
forage x the energy digestibility coefficient
in percent) were calculated (Crampton et al.,
Experiment I. Chopped, artifically dried
alfalfa hay, containing 15.8% crude protein
(oven-dry basis) was fed to half the lambs
in the digestion cages and to half the lambs
in the pen. The remaining lambs were fed
chopped, artificially-dried slough hay, containing 10.0% crude protein. Caged lambs had
access to water at all times, and penned lambs
at all times except during their feeding
periods. The experiment was conducted for
32 days.
Experiment II. The rations described for
Experiment I were continued for a further
21-day period. However, two of the caged
lambs and two of the penned lambs on each
roughage were permitted access to water
during feeding periods; the remaining two
lambs on each treatment were not.
Experiment III. All lambs were fed a
finishing ration of 2/3 whole barley (10.6%
crude protein) and 1/3 chopped roughage
T A B L E 1. A V E R A G E S OF D A I L Y W E I G H T GAINS, D A I L Y ~FEED C O N S U M P T I O N AND
D I G E S T I O N C O E F F I C I E N T S I N E X P E R I M E N T S I AND I I
Method of confinement
Item
Initial weight, kg.
Final weight, kg.
Daily gain, kg.
D.M. intake per day, kg.
D.M. per kg. gain, kg.
Daily D.M./kg. metabolic wt., ~ gm.
Daily dig. D.M./kg. metabolic wt., gm.
Relative intake
Nutritive value index
Dry matter digestibility, %
Experiment I
Experiment I I
Crude protein digestibility, %
Experiment I
Experiment I I
Gross energy digestibility, %
Experiment I
Experiment I I
P~.05.
** P<.O1.
a Liveweight in kilograms to the 3~ power.
Caged Penned
Error
mean
square
........
........
0.0005
0.007
202.51
52.53
15.30
........
........
Type of roughage
Slough
Alfalfa hay
26.2
31.2
0.10
0.81
8.10
66
37
82
45
26.1
30.4
0.08
0.80
10.00
65
36
82
44
56
57
55
55
4.91
3.27
58
58
52
54
5.05**
1.93
63
70
60
67
3.77
1.55"
67
73
56
64
8.38**
2.41"*
54
55
52
53
56
56
51
52
6.40**
2.39**
10.21
5.83
26.3
34.0
0.15
1.04
6.93
82
48
102
57
Error
mean
square
26.0
27.7
0.03
0.57
19.00
49
26
61
32
........
........
0.0007**
0.0007**
176.52"
18.91"*
7.71"*
........
........
(Pr.07)
GRIEVE AND BEACOM
630
1960) and found to be essentially the same
for caged and penned lambs.
The methods of confinement had little
effect on digestibility of the rations (table
1). Digestion coefficients were essentially
equal for dry matter and gross energy under
the two methods of confinement, and there
was close agreement between Experiments I
and II. Digestibility of crude protein was
higher in both experiments with caged lambs
than with penned lambs, and was higher with
both groups in Experiment II than in Experiment I.
Since differences in digestion coefficients
were slight between caged and penned lambs
only 9% of those made by the lambs fed
alfalfa. The Nutritive Value Indexes of
slough hay and alfalfa were 57 and 32, respectively.
Digestibility of dry matter, crude protein
and gross energy was significantly lower in
slough hay than in alfalfa (table 1). The
digestibility of dry matter and gross energy
in both roughages agreed closely in Experiments I and II, but digestibility of crude
protein in both roughages was higher in
Experiment II than in Experiment I.
Experiment IlL There was little difference
in the performance of lambs confined by the
two methods when they were fed finishing
T A B L E 2. A V E R A G E S OF D A I L Y W E I G H T GAINS, D A I L Y F E E D C O N S U M P T I O N A N D
D I G E S T I O N C O E F F I C I E N T S IN E X P E R I M E N T III
T y p e of roughage
M e t h o d of confinement
Item
Initial weight, kg.
Final weight, kg.
Daily gain, kg.
D.M. intake per day, kg.
D.M. per kg. gain, kg.
Daily D.M./kg. metabolic wt., a gm.
Daily dig. D . M . / k g . metabolic wt., ~ gin.
Digestion coefficients
D r y matter, %
Crude protein, %
Gross energy, %
Caged
Penned
Error
mean
square
31.2
35.8
0.16
1.20
7.50
87
59
30.4
35.1
0.17
1.25
7.35
92
62
.......
.......
0.0001
0.007
0.36
28.11
11.82
68
57
68
67
58
67
6.67
8.81
9.68
Red
clover
Brome
hay
34.0
38.8
0.17
1.40
8.24
95
65
27.7
32.1
0.16
1.06
6.62
84
55
69
58
68
.66
56
67
Error
mean
square
.......
";i;;;2
0.013"*
8.69
26.67**
1.45"*
12.05
22.25
12.25
P<.05.
~ P~.01.
a Liveweight in kilograms to the ~ power.
fed alfalfa, the apparent reduction in the
digestibility of crude protein by penned lambs
was due largely to the differences in digestibility by lambs on slough hay. In Experiment
I, digestion coefficients for crude protein for
caged and penned lambs were 67 in both
cases when fed alfalfa, while in Experiment
II they were 74 and 73 for caged and penned
lambs, respectively. For lambs on slough hay
the coefficients were 59 and 54 during the first
32 days, and 66 and 62 during the subsequent
21 days, with caged lambs having the higher
coefficient in each case.
Marked differences were found in the
performance of lambs fed the two roughages
(table 1). The daily intake of dry matter
was 45% less for lambs fed slough hay than
for those fed alfalfa. Also, the intake of dry
matter per unit of metabolic weight was 40%
less for the lambs fed slough hay. As a result
their gains were considerably lower, averaging
rations (table 2). Caged and penned lambs
consumed approximately the same amount of
dry matter daily, gained at similar rates and
digested similar proportions of dry matter,
crude protein and gross energy. Penned lambs
consumed slightly more dry matter daily per
unit of metabolic weight than caged lambs
but this difference was not statistically
significant.
Differences between rations (table 2) were
less marked than in the previous two experiments. Lambs fed the finishing ration
containing brome hay consumed less dry
matter per day and per unit of metabolic
weight than those fed the ration containing
red clover. However, both groups of lambs
gained at approximately the same rate and
lambs fed the brome hay ration used their
feed somewhat more efficiently. Digestibility
of dry matter, crude protein and gross energy
tended to be higher in the red clover than in
CAGED VERSUS P E N N E D LAMBS
the brome hay ration, but the differences
were small and not significant.
Discussion
There was little difference between the performance of the caged and penned lambs in
this study when they were fed high or low
quality roughage rations, or when they were
fed finishing rations containing barley and
roughage. Data obtained by feeding lambs
confined in the metabolism unit or in a pen
would appear equally applicable to practical
feeding conditions.
These results differ from other reports
(Church and Fox, 1959; Lawrence and
Troelsen, 1961), where it was noted that feed
consumption and rate of gain were depressed
when lambs and yearling wethers were confined in stalls. However, the comparison of
these results to those found by Church and
Fox is not strictly valid since in their work
pen-fed lambs had ad lib access to feed,
whereas stall-fed lambs did not. In the present
study appetite was not depressed when lambs
were confined in cages for 81 days. This suggests that lack of exercise due to close confinement did not cause the depressed appetite
that was noted in previous reports. Usually
in experiments of this type the metabolism
cages keep the lambs completely separated,
and this isolation, more than confinement or
lack of exercise, could be a major factor in
appetite depression. In the study reported
here the metabolism unit permitted each
lamb to maintain visual and, in a limited
degree, physical contact with one or two
other lambs. This lack of isolation may have
accounted for the absence of appetite depression.
In this study, lambs on slough hay consumed less feed than those fed alfalfa. Since
lower coefficients of digestibility would tend
to reduce the rate of food passage through
the digestive tract and thus reduce feed
consumption (Blaxter et al., 1961), the
lower digestibility of slough hay could be the
major factor responsible for depressed appetites on this feed. Feed intake should not
have been depressed because of a protein
deficiency, since the slough hay supplied 5.6
to 6.4% digestible crude protein, compared
with 6.0% or less required by lambs of the
weights in this study (N.R.C., 1957).
It was apparent that chemical analyses did
631
not indicate the marked difference in feeding
value between slough hay and alfalfa. This
emphasized the need for other measures of
forage quality, such as the Nutritive Value
Index. In this experiment the Nutritive Value
Index of slough hay was 44% lower than that
of alfalfa, and this closely approximated the
difference in daily intake of dry matter.
Summary
The performance of lambs confined in individual cages in a metabolism unit was compared with that of lambs confined in a pen
and individually fed for a period of 81 days.
Lambs confined in cages consumed approximately the same amount of dry matter
daily and per unit of metabolic weight, and
gained at approximately the same rate as
those confined in pens, when fed all-roughage
rations of slough hay or alfalfa and finishing
rations of 1/3 hay and 2/3 barley.
Digestibility of crude protein in alfalfa and
the finishing rations, and of dry matter and
gross energy in all rations, was very similar
with caged and penned lambs. Digestibility
of crude protein in slough hay was lower
when fed to penned lambs than when fed to
caged lambs.
The feeding value of slough hay was much
lower than that of alfalfa. Lambs fed slough
hay consumed 55% as much dry matter
daily and gained 20% as much weight per
day as those fed alfalfa. The Nutritive Value
Index of slough hay was 32, compared with
57 for alfalfa.
L i t e r a t u r e Cited
A.O.A.C. 1960. Official Methods of Analysis (9th ed.)
Association of Official Agricultural Chemists, Washington, D. C.
Blaxter, K. L., F. W. Wainman and R. S. Wilson.
1961. The regulation of food intake by sheep. An.
Prod. 3:51.
Church, D. C. and C. W. Fox. 1959. Lamb response
to three experimental feeding methods. J. Animal
Sci. 18:1168 (Abstr.).
Crampton, E. W., E. Donefer and L. E. Lloyd. 1960.
A nurtitive value index for forages. J. Animal Sci.
19:538.
Lawrence, Donna J. and J. E. Troelsen. 1961. The
effect of digestion stalls upon the performance of
yearling wethers. Proc. Canadian Soc. An. Prod.,
p. 31.
N.R.C. 1957. Nutrient Requirements of Domestic
Animals. No. 5. Nutrient Requirements of Sheep.
National Research Council, Washington, D. C.