UNIVERSITY OF CALIFORNIA

COLLEGE OF AGRICULTURE

AGRICULTURAL EXPERIMENT STATION

BERKELEY, CALIFORNIA

FEEDING
THE YOUNG PIG

E. H. HUGHES AND HUGH HART

BULLETIN 578

JULY, 1934

UNIVERSITY OF CALI FORNIA
BERKELEY, CALIFORNIA

Digitized by the Internet Archive

in 2012 with funding from

University of California, Davis Libraries

http://www.archive.org/details/feedingyoungpig578hugh

FEEDING THE YOUNG PIG 1

E. H. HUGHES 2 and HUGH HAET 3

INTRODUCTION

Because the young pig grows rapidly from weaning time until it
reaches a weight of 75 pounds, it cannot be fed according to the stand-
ards for the mature animal. In early life, its weight may be doubled in
8 to 14 days. At birth it usually weighs from 1.5 to 4 pounds; at weaning
time, from 30 to 45 pounds; at 200 days often 200 pounds; and at ma-
turity (about 2 years), from 300 up to as much as 1,000 pounds.

The experiments reported herein were planned with two objectives in
view: first, to devise diets without skim milk, buttermilk, or whey, to
carry the pig successfully from weaning up to a weight of 75 pounds;
second, to study the effect of these early diets upon the animal's later
growth, development, and fattening, especially when fattening rations
include barley as a major energy foodstuff.

RATIONS AND FEEDS USED

The following feeds were selected because they contained the necessary
nutrients and accessory factors as well as being available to California
producers.

For rapid gain, it seemed necessary to provide rations having a low
fiber content; a protein content of about 17 per cent; a sufficiency of
vitamins A, B, D, and G; adequate mineral matter, particularly calcium
and phosphorus, for optimum development of the skeleton and for
other metabolic processes; and enough energy, water, and sunlight for
growth and normal well-being.

Barley used in these experiments was steam-rolled, locally grown feed
barley of good quality — the most generally fed energy-producing cereal
of the Pacific Coast, and an excellent source of phosphorus. As a feed
for young pigs, it has certain limitations : its fiber content is somewhat
higher than desirable, its supply of calcium and of vitamins A and D is
low, and its protein is not adequate in quantity or quality for the rapidly
growing young animals.

Brewer's rice, a locally grown by-product of the rice-milling indus-
try, furnishes abundant energy and is practically free of fiber. The
protein, ash, and vitamin contents, however, are very low.

i Received for publication March 16, 1934.

2 Associate Professor of Animal Husbandry and Associate Animal Husbandman
in the Experiment Station.

3 Swine Herdsman.

[3]

4 University of California — Experiment Station

Dried skim milk contains casein and other milk proteins; lactose, a
source of energy ; and considerable calcium and phosphorus, with other
minerals.

Tankage, a by-product of the meat-packing industry, contains an ex-
tremely rich supply of protein, plus considerable calcium and phos-
phorus.

Fish meal, a by-product of the fishing industry, is, like tankage, rich
in protein; and it has a similar calcium and phosphorus content.

Wheat middlings contain about 17 per cent protein, abundant phos-
phorus, but little calcium. This is a popular swine feed, giving the ration
palatability and some bulk without materially increasing the percentage
of fiber.

Linseed oil meal contains a percentage of protein about one-half that
of tankage. Because of the oil content, it is slightly laxative. Though rich
in phosphorus, it is somewhat lacking in calcium.

Chopped alfalfa hay of good quality was used, cut so that the longest
pieces of the stem measured about 1 inch. This feed is relatively high in
protein, in the fat-soluble vitamins, and in calcium; but it contains
more fiber than any of the other feeds used.

Mineral supplements fed included only salt and calcium carbonate.

Vitamins furnished the pigs in these studies were those naturally
present in the feeds provided.

Water, shelter, shade, and sunlight were freely provided for the ex-
perimental animals.

EQUIPMENT, FEEDING, AND ANIMALS USED

All feed lots used were of the same dimensions and were paved with con-
crete. The houses, self-feeders, and water troughs were similar in size,
construction, shape, and position. Before being put into the feeders, the
feed was weighed and thoroughly mixed. Any part refused was deducted
from the original weight. When two lots were pastured at the same time,
the pasture was similar in kind and in area.

The pigs used in these experiments were purebred Duroc- Jerseys and
Poland Chinas, bred and raised at this Station. At the outset, the lots
were divided as uniformly as possible, according to weight, thrift, sex,
age, and breed.

The pigs of the first experiment were farrowed in September or early
in October, 1932; those of the second, in March, 1933. Both groups had
been fed normal diets and had free access to pasture with their mothers
before weaning.

Bul. 578]

Feeding the Young Pig

EXPERIMENTAL PROCEDURE

Two experiments were conducted, each divided into two parts (desig-
nated as experiments 1A and B; and experiments 2 A and B). The first
dealt with pigs from the time of weaning till they weighed about 75
pounds; the second, with the same individuals throughout fattening.
The rations were changed at the beginning of the second period, and all
pigs were weighed individually each week. In order that the two divi-
sions of the tests might be recognized readily, numerals were assigned
to the lots in the first part, whereas letters were used for lots in the sec-
ond phase of each experiment.

The animals in lots A, B, etc., in experiments IB and 2B were taken
equally from lots 1, 2, etc., of experiments 1A and 2A. Having individ-

TABLE 1
Percentage Composition" of the Feeds Used

Water

Ash

Crude
protein

Carbohydrates

Fat

Calcium

Feed

Fiber

Nitrogen-
free
extract

Phos-
phorus

9.20
9.49
7.14
9.26
9.75
8.55
9.10

10.56

2.17
54
7.94
16.24
13.58
2.19
5 40

9.22

10.95
7.40
34.89
59.31
66.81
16.98
33.90

19.35

4 54
trace
trace
1 30

trace
2.78
8.40

19.26

71 33

82.17
49.79
6.24
4.69
66 20
35.70

39.65

1 81
0.40

28
8.95
5.27
3 30
7.50

1.96

074
045
1.260
4.500
4 240
0.074
0.364

1.023

0.332

Brewer's rice

Dried skim milk..

0.106

1 060

2 770

3 060

Wheat middlings
Linseed* oil meal
Chopped alfalfa

441
0.742

0.309

* Henry, W. A., and F. B. Morrison. Feeds and feeding, a handbook for the student and stockman.
p. 711. Henry-Morrison Co., Madison, Wisconsin. 1923.

TABLE 2
Digestible Nutrients of the Feeds Used*

Total

dry matter in

100 pounds

Digestible nutrients in 100 pounds

Feed

Crude
protein

Carbo-
hydrates

Fat

Total

Nutritive
ratio

pounds
90 80
90.51
92.86
90.74
90.25
91.45
90.90
89.44

pounds
8.43
4 59
34.89
42.11
47.44
14.09
28.82
13.74

pounds
63.48
75.60
49.79
6 24
4.69
57.76
30.61
36.83

pounds
80
36
0.28
8.95
5.27
2.74
5.25
0.74

pounds
73.71
81.00
85.31
68.49
63.99
78.02
71.24
52.24

1
1

7.74

16.65

Dried skim milk

1.44

0.63

0.35

4 54

1.47

Chopped alfalfa hay....

2.80

* Figures used in computing this table from Henry, W. A., and F. B. Morrison. Feeds and feeding,
hand book for the student and stockman, p. 722-727. Henry-Morrison Co., Madison, Wisconsin. 1923.

6 University of California — Experiment Station

ual earmarks, each could be followed from one part of the experiment
into the next.

The initial and final weights of the pigs in experiments 1A and 2A
were about 32 to 75 pounds, respectively. In experiments IB and 2B the
initial weights approximated 75 pounds; and each pig was taken from
the fattening pens upon reaching 200 pounds.

Throughout these experiments the individuals were observed criti-
cally for any lameness or stiffness, and for growth, thrift, and condition.

COMPOSITION OF THE FEEDS

Table 1 gives the percentage composition of all concentrates and of the
alfalfa hay used in these tests. Except for linseed oil meal, the analyses
reported were made at this Station. The percentage of dry matter, of
digestible nutrients, and the nutritive ratios for the feeds appear in
table 2. From the data in these two tables were determined the total
digestible nutrients, the nutritive ratio, and the amounts of calcium and
phosphorus in the experimental rations.

EXPERIMENT 1A

In developing diets for young weaned pigs, certain commonly accepted
facts and impressions were considered. For these rapidly growing
animals with a limited capacity, the rations used were relatively high
in protein, mineral matter, energy, and accessory factors, but low in
fiber. Palatability of and variety in the diet were also believed to be
important.

The three groups of pigs were fed in dry lot during the first part of
the experiment.

Rations Used in Experiment 1A. — The basal ration contained rolled
barley, 30 pounds; brewer's rice, 30 pounds; wheat middlings, 15
pounds; linseed oil meal, 5 pounds; chopped alfalfa hay, 5 pounds; salt,
1 pound; and calcium carbonate, 1 pound.

Lot 1 received the basal ration plus dried skim milk, 15 pounds.

Lot 2 received the basal ration plus tankage, 15 pounds.

Lot 3 received the basal ration plus fish meal, 15 pounds.

As shown by table 3, the total dry matter in each ration was practi-
cally the same. There was a difference of about 1 per cent in the digesti-
ble crude protein in each, the content being least in lot 1 and greatest in
lot 3. Lot 1 received a diet higher in digestible carbohydrates and total
digestible nutrients and lower in fat than did the other groups. It had
the widest nutritive ratio, with lots 2 and 3 following in the order named.
Though the ratio of calcium to phosphorus does not differ greatly in the
three rations, the smallest total amount of these substances was fed to
lotl.

Bul. 578]

Feeding the Young Pig

Experiment 1A began November 26, 1932, and ended January 14,
1933, having covered a feeding period of 49 days. In group 3 two pigs
that died early in the experiment were not included in the results. Most
of the pigs were weaned about a week before the test started and during

TABLE 3

Digestible Nutrients, Nutritive Ratios, and Mineral Constituents of the
Rations Used in Experiment 1A

Total dry
matter in
100 pounds

Digestible nutrients in 100 pounds

Nutritive
ratio

In 102 pounds of feed
mixture

Lot

Crude
protein

Carbo-
hydrates

Fat

Total

Calcium

Phosphorus

1
2
3

pounds
91 06
90.74
90.67

pounds
13.38
14.46
15.26

pounds
61.23
54 70
54.47

pounds
1.10
2.40
1.85

pounds
77.09
74.56
73.89

1 :4.75
1 : 4.18
1 : 3.84

pounds
0.705
1.191
1.152

pounds
0.409
0.666
0.709

that week were fed barley, tankage, wheat middlings, salt, lime, and
alfalfa or green barley pasture.

Throughout this part of the experiment most of the pigs grew fast. A
few, however, did not thrive so well as the rest. In lot 2 one barrow and
one gilt gained less rapidly than their mates. The eyes of the barrow

TABLE 4
Results of Experiment 1A

Lot

Number of
pigs

Average
initial
weight

Average

final
weight

Average
daily
gain

Feed consumed

for 100 pounds

of gain

Dry matter con-
sumed for 100
pounds of gain

2
3

18
18
16

pounds
32 11
31.56
31.69

pounds
83.56
72 33
79.13

pounds
1 05
0.83
0.97

pounds

288 55
318.26
290.25

pounds

262.75
288.79
263.17

watered; his hair was dry, harsh, and curly. In group 3 a barrow, at the
end of the test, was very thin, his hair long, his tail straight, and his
backbone very prominent. Several pigs, scattered throughout the lots,
exhibited sore feet and some stiffness, probably caused by the rough
concrete on which they were confined. The condition of the pigs in lot 1
was, however, such that they were all carried on into the second phase.
Table 4 shows an excellent average daily gain for pigs weighing
from 32 to 75 pounds. The animals fed tankage gained less rapidly and
consumed more feed per unit of increase than those fed dried skim milk
or fish meal. The pigs fed dried skim milk gained more rapidly and
utilized their feed somewhat more efficiently than those on fish meal.
The pigs in lot 1 were somewhat superior in thrift to those fed tankage
or fish meal, and made more consistent gains from week to week.

University of California — Experiment Station

EXPERIMENT IB

Experiment IB was intended, first, to determine whether or not the
character of the early feeding of pigs after weaning had any effect on
their fattening; and, second, to increase the general knowledge of fat-
tening rations. At the conclusion of the first part, the thrifty pigs were
divided into two groups containing 24 pigs each. One half of those in
each lot in the first part were placed in lot A; the other half, in lot B. Of
these, 18 were from lot 1, 16 from lot 2, and 14 from lot 3. They were
placed on feed January 14, 1933.

Rations Used in Experiment IB. — Lot A received the following
ration :

Feed Pounds

Rolled barley 84

Dried skim milk 3

Tankage 3

Fish meal 3

Chopped alfalfa hay : 5

Salt 1

Calcium carbonate 1

Lot B received the following ration :

Feed Pounds

Rolled barley 90

Chopped alfalfa hay 8

Salt 1

Calcium carbonate 1

Pasture (a mixture of barley, alfalfa, and natural grasses).

Except for the pasture available to the second group, the two rations
differed little in total dry matter or in total digestible nutrients (table
5). The digestible crude protein, the calcium, and the phosphorus were
higher in the ration fed to lot A ; and the nutritive ratio was also con-
siderably narrower. The green pasture accessible to the pigs in lot B
provided some additional protein, and their feed had a higher vitamin
A content than that of the other lot. As to protein and the- nutritive
ratio, the diet of lot A seemed superior to that of lot B.

TABLE 5

Digestible Nutrients, Nutritive Ratios, and Mineral Constituents o<f the
Rations Used in Experiment IB*

Total dry
matter in
100 pounds

Digestible nutrients in 100 pounds

Nutritive
ratio

In 100 pounds of feed

Lot

Crude
protein

Carbo-
hydrates

Fat

Total

Calcium

Phosphorus

A
B

pounds
88.96
88.88

pounds
11.50

8.69

pounds
56.99
60.08

pounds
1.14
0.78

pounds
71.06
70.52

1 :5 18
1 : 7.12

pounds
0.813
0.548

pounds
0.501
0.324

* The pasture available to lot B is not included.

Bul. 578]

Feeding the Young Pig

The feed of lot A contained small quantities of all the protein concen-
trates compared and contrasted in the first phase of this experiment.
The nutritive ratio was about normal for pigs of the age and weight
fed. Such a ration, the authors believed, would furnish valuable in-
formation on the effect of the previous feeding while the pigs were fat-
tening. The other ration, though probably less satisfactory from a nutri-
tional standpoint, had the advantage of containing home-grown feeds.

On April 22, when this test was finished, 8 pigs in lot A and 3 pigs in
lot B had not reached 200 pounds.

The average daily gain was obtained by dividing the total gain of all
the animals in each group by the total number of pigs multiplied by the
number of days they were on feed.

Eesults

TABLE 6

of Experiment

Lot

Number of
pigs

Average
initial
weight

Average
daily
gain

Feed consumed

for 100 pounds of

gain*

Dry matter
consumed for 100
pounds of gain*

A
B

24
24

pounds
82.33
79.33

pounds
1.19
1 29

pounds
441.59
422.07

pounds
392.84
375 14

* Pasture accessible to pigs in lot B is not included.

When the experiment ended there were 5 sore-footed pigs and 1 very
stiff pig in lot A; and 1 stiff pig in lot B. This sore-footedness among the
pigs of lot A was probably caused by standing and walking on rough
concrete, Their toes were worn very short.

It was surprising to find (table 6) that the pigs in lot A gained less
rapidly than those in the other lot — less rapidly than would be expected
from the ration fed. Though the diet of lot B had a wide nutritive ratio,
gains were satisfactory and more rapid than in lot A; the pasture, no
doubt, had a beneficial influence.

EXPERIMENT 2A

A second experiment was conducted to check the results of the first. As
the same feeds were used, table 1 and 2 again apply. The pigs used were
purebred Poland Chinas and Duroc-Jerseys, about the same in age and
weight as those of the first experiment. There were some differences in
the two tests, the first being conducted with fall pigs and the second
with spring pigs. In the second trial, furthermore, the pigs were put on
the diets immediately after weaning; those in the first test had been
weaned a few days before the study began. Additional lots were in-
cluded in both parts of the second experiment.

A group of 80 thrifty, uniform pigs were used for this part of the

University of California — Experiment Station

work. The test began May 20, 1933, and closed July 1, 1933, covering a
feeding period of 42 days. Four lots of pigs were fed. Lots 1, 2, and 3
received the same rations as the corresponding lots in experiment 1A.
Lot 4 was fed the same diet as lot 1 and had, in addition, free access to
Sudan grass pasture.

See table 3 for the digestible nutrients in 100 pounds of each ration,
for the nutritive ratio, and for the amounts of calcium and phosphorus.

Lot 4 was added in an attempt to ascertain the effect of green forage
on a supposedly adequate diet. The pasture added succulence, some
carbohydrates, protein, ash, and considerable vitamin A.

Table 7 shows practically identical gains for pigs in lots 1 and 3, fed,

TABLE 7
Eesults of Experiment 2A

Lot

Number of
pigs

Average
initial
weight

Average

final
weight

Average
daily
gain

Feed consumed

for 100 pounds

of gain

Dry matter con-
sumed for 100
pounds of gain

1
2
3
4

19*
20
20
20

pounds
32.63
32.10
32.80
32.90

pounds
72.21
68.30
73.10
78.90

pounds
0.94
0.86
0.96
1.09

pounds
276.57
294.24
284.86
251 09t

pounds
251.84
266.99

258.28
228. 64 1

* A pig in this lot drowned during the first week of the experiment,
t Sudan pasture consumed by pigs in this group is not included.

respectively, the basal ration plus dried skim milk, and the basal ration
plus fish meal. Lot 2 (the tankage-fed pigs) gained somewhat less, and
lot 4 somewhat more, than lots 2 and 3. Pasture-fed pigs (lot 4) gained
faster and required approximately 25 pounds less concentrates for 100
pounds of gain than the pigs in lot 1, which received the same ration
without pasture. Lot 3, fed fish meal, required more feed per unit of gain
than lot 1, fed dried skim milk; while lot 2, fed tankage, required more
feed for 100 pounds of increase than the other groups. Free access to
pasture gave lot 4 a distinct advantage over all other groups, both in
rate and in economy of gain.

Following this part of the experiment, all the pigs were arbitrarily
graded into three classes, according to condition, growth, and thrifti-
ness. In this grouping, the order of merit Avas as follows : lot 4, lot 1,
lot 3, and lot 2. Because of a lack of thriftiness and physical well-being,
one pig from lot 2 and one from lot 3 were not included in the second
part of the experiment. Lot 4 was a very thrifty, uniform lot.

EXPERIMENT 2B v
The first part of this experiment having been concluded, 75 of the pigs
were divided as equally as possible into three groups. In addition to
A and B, which were fed like the corresponding groups in the first ex-

Bul. 578]

Feeding the Young Pig

periment, lot C was added. It was fed the same ration as lot A, but had,
in addition, access to Sudan pasture.

On July 1, 1933, the pigs were sorted, divided, and weighed; and the
experiment began. It was concluded October 21, 1933, having covered a
feeding period of 112 days.

Table 8 summarizes experiment 2B. Though the rations fed A and B
differ greatly, the two groups gained at the same rate. In feed consumed
for 100 pounds of gain, lot A without pasture was more economical.
Although A and C had the same diet, except that the latter had free
access to Sudan grass pasture, lot C gained much faster and consumed
less concentrates per unit of increase. The beneficial effect of green pas-
ture was demonstrated.

TABLE 8
Results of Experiment 2B

Lot

Number of
pigs

Average
initial
weight

Average
daily
gain

Feed consumed

for 100 pounds of

gain*

Dry matter
consumed for 100
pounds of gain*

A
B

25
25
24f

pounds
73.68
74.88
73.90

pounds
1 25
1.24
1.49

pounds
381 . 70
392.27
367.97

pounds
339.56
348.65
327.35

* Sudan pasture accessible to pigs in groups B and C is not included.

t A pig in this group broke a leg the first week of the test and was taken out.

After the experiment, there remained from lots A and B several pigs
that had not been marketed. At slaughter, the livers of five pigs from
each group were tested for vitamin A by the antimony trichloride
method. The concentration of this substance in the livers of the pastured
pigs was more than four times greater than for those fed in dry lot.

Upon attaining the weight of about 200 pounds, each pig was removed
from the experiment. When the groups were compared, lot C was
strikingly superior to A and somewhat superior to B. The pigs in B and
C had access to pasture.

During the experiment, 6 pigs in group A developed stiffness, became
tender-footed, or walked with an abnormal gait; and one pig in lot C
contracted an abscess of the throat.

DISCUSSION OF EESULTS

Tables 9, 10, 11, and 12 summarize the experiments. Enough animals
were fed to make the results significant.

The outstanding fact indicated in table 9 is the beneficial effect of
pasture, as shown by the rate of gain and the amount of feed per unit of
increase of the pigs in lot 4. They gained nearly 10 per cent faster and
consumed about 31.50 pounds less concentrates for 100 pounds' gain

University of California — Experiment Station

than lot 1, fed the same ration without pasture. The pigs on tankage
(lot 2) gained more slowly and consumed more feed per unit of increase
than the other lots.

Table 10 summarizes the fattening phase of the experiments. The
value of pasture is evident. Lots A and C received the same ration
except that A was fed in dry lot, while C had access to pasture. The
latter gained ^ pound more per head daily than lot A. For each 100

TABLE 9
Eesults of Experiments 1A and 2A

Lot

Number of
pigs

Average
initial
weight

Average

final
weight

Average
daily
gain

Feed consumed

for 100 pounds

of gain

Dry matter con-
sumed for 100
pounds of gain

pounds
32.38

pounds
77.73

pounds
0.99

pounds
282.56

pounds
257.30

31.84

70.21

0.85

306.25

277.89

32.31

75.77

0.96

287.56

260.73

32.90

78.90

1.09

251. 09f

228 64f

* Only one experiment.

t Sudan pasture consumed is not included.

TABLE 10

Results of Experiments IB and 2B

Lot

A
B
Cf

Number of
pigs

Average
initial
weight

pounds
77.90
77.06
73 90

Average
daily
gain

pounds
1.22
1.26
1.49

Feed consumed

for 100 pounds of

gain*

pounds
411.65
407.17

367.97

Dry matter
consumed for 100
pounds of gain*

pounds
366 20
361.90
327.35

* Sudan pasture accessible to pigs in groups B and C is not included,
t Only one experiment.

pounds of gain, the pasture-fed pigs consumed approximately 40 pounds
less concentrates than those fed in dry lot. As indicated in the footnotes
to tables, no effort was made to estimate the amount of green forage
consumed by those pigs having access to pasture.

Lot B received a ration with a very wide nutritive ratio but had access
to pasture. They gained just as fast as lot A, which had no pasture.

Though the number of pigs in the various groups is not large, table 11
demonstrates certain trends. An adequate diet produced rapid gains for
the pigs in lot C, and the earlier diet had no apparent effect in this
instance. The average daily gains of lot B (on a ration with a wide
nutritive ratio) were less rapid than those of lot C; however, as in lot C,
early feeding caused no significant difference. Both B and C had free
access to green forage. The previous diet seemingly did affect the rate of
gain in lot A. The pigs fed the basal rations plus dried skim milk in one

Bul. 578]

Feeding the Young Pig

case and tankage in another gained the same amount, while those on fish
meal gained more slowly. The pigs given dried skim milk, with access to
pasture, gained more rapidly than either of the other groups.

TABLE 11

summaey of effect of the early feeding on the rate of gain during

Fattening
(Both experiments)

Number of pigs

Average daily

Lot designation

transferred from

gain during

second part

Ration, first part of experiments

first to second

the second part

of experiment

part of the

of experiments,

experiments

in pounds

Receiving as ration, second part of experiments: rolled barley, dried skim milk, tankage, fish
chopped alfalfa hay, salt, and calcium carbonate

Basal ration* plus dried skim milk

Basal ration, plus tankage

Basal ration, plus fish meal

Basal ration, plus dried skim milk and pasture

1.26
1.05
1.38

Receiving as ration, second part of experiments: rolled barley,
salt, calcium carbonate, and pasture

jhopped alfalfa hay,

Basal ration, plus dried skim milk

Basal ration, plus tankage

Basal ration, plus fish meal

Basal ration, plus dried skim milk and pasture

1.31
1 25
1 24
1.25

Receiving as ration, second part of experiments: rolled barleVj^drjgd Rk'r"^"' 11 ^, tankage, fish meal,
chopped alfalfa hay, salt, calcium carbonate, and pasture

[ Basal ration, plus dried skim milk

Basal ration, plus tankage

Basal ration, plus fish meal

Basal ration, plus dried skim milk and pasture

1.47
1.51
1.48
1.51

* Basal ration for all groups: rolled barley, brewer's rice, wheat middlings, linseed oil meal, chopped
alfalfa hay, salt, and calcium carbonate,
t Only one experiment.

Table 12 shows more rapid gains for pigs weighing between 75 and
200 pounds than for smaller pigs weighing 32 to 75 pounds. Because of
an increased maintenance requirement, the heavier pigs required much
more feed per unit of gain than the lighter ones. Comparing the amount
consumed for 100 pounds' gain by the lighter and the heavier pigs, fed
without pasture, we find that the heavier pigs required 120 pounds more
feed for this gain than those between 32 and 75 pounds.

Very little experimental information is available to guide the pro-
ducer in feeding the young weaned pig. Henry and Morrison 4 suggest a
nutritive ratio of 1 :4.0 or 1 :4.5 for pigs not on pasture, and of 1 :5.0 or
1 :6.0 for pigs with access to good forage. They state further that pasture
is especially beneficial to young growing pigs.

4 Henry, W. A., and F. B. Morrison. Feeds and feeding, a handbook for the stu-
dent and stockman, p. 700. Henry-Morrison Co., Madison, Wisconsin. 1923.

University of California — Experiment Station

For the experiments reported in this paper, a basal ration was formu-
lated to suit the rapid growth and limited capacity of the young pig.
Except for its protein content, this diet appeared, in the light of our
present knowledge, sufficient. To the basal diet was added an animal
protein — dried skim milk for one lot, tankage for another, and fish meal
for a third. Because certain pigs in dry lot in experiment IB (the fatten-
ing period) , gained less rapidly than expected, a fourth group, added in

TABLE 12

Kate of Gain and Feed Consumed for a Unit of Increase

as Affected by Size

Weight of pigs

Number of
pigs

Ration

Average daily
gain

Feed consumed

for 100 pounds of

gain

-pounds
32- 75

112
20
49
49

pounds
0.93
1.09
1 22

1.27

1 49

pounds
291 65

32- 75

251 08*

75-200

411 38

75-200

With pasture and wide nutritive

407 17

75-200

With pasture and adequate nutri-

367 98*

* The pasture consumed is not included.

experiment 2B, received the basal ration plus dried skim milk, with free
access to pasture. Because of the green forage in their diet, they gained
more rapidly and required less concentrates for 100 pounds' gain than
any other group.

The pigs fed tankage with the basal ration did not gain so fast nor so
economically as those fed dried skim milk or fish meal. This fact cannot
be explained by the nutritive ratio, for the dried skim milk diet con-
tained less protein than either of the others. The best explanation is that
the protein of the tankage in these rations had a lower biological value
than did the proteins of skim milk powder or fish meal. As McFarlane
and Fulmer 5 have shown, fish meal and buttermilk powder (which re-
sembles dried skim milk in composition) contain a higher percentage of
tyrosine and tryptophane than does tankage.

That the type of early feeding did affect the pigs during fattening
was indicated in experiment 2B. Pigs given access to pasture from wean-
ing time until they attained a weight of about 75 pounds gained more
rapidly when fattened in dry lot than did pigs fed apparently good
rations without pasture. The effect of pasture in experiment 2A (lot 4),
did not manifest itself when the pigs had access to green forage during
fattening. Probably the young pigs did not obtain sufficient vitamin A

5 McFarlane, Wm. D., and Hugh L. Fulmer. The colorimetric determination of the
tryosine and tryptophane content of various protein concentrates. Biochem Tour
24:1601-1610. 1930.

Bul. 578] Feeding the Young Pig 15

from the basal ration; their requirements in this respect have not been
accurately determined. Barley 6 is known to contain little vitamin A,
and the only concentrated source in the basal diet was the chopped
alfalfa hay. As this hay constituted only 5 per cent of the rations during
the first phase of both experiments, it apparently did not yield enough
vitamin A to satisfy the needs of fast-growing pigs without green for-
age. Though the data presented warrant no definite conclusions, they
agree with the report of Bohstedt 7 , who found that pigs gained faster
on a ration of white corn, wheat middlings, linseed meal, salt, and green
forage than those on the same diet without pasture. The pasture con-
tained some growth-promoting substance that the pigs were not able to
get from the dry-feed mixture. In these studies, free access to pasture
had a beneficial effect on the rate of gains and on thrift. The energy,
protein, ash, accessory factors (particularly vitamin A) , and succulence
of the green forage all probably influenced these results.

During the early feeding the pigs fed tankage gained less rapidly
than the others; but during the fattening period, they gained at least as
fast as any pigs except those that had received green forage.

Some significant information on fattening pigs was secured during
these experiments. Pigs weighing from 75 to 200 pounds, given pasture
and fed a ration with sufficient energy, protein, calcium, and phos-
phorus, made an average daily gain of 1.49 pounds and produced 100
pounds of gain on 367.98 pounds of concentrates. These rapid and effi-
cient gains indicate the value of a diet sufficient in all its factors, for
rapid and economical pork production. Another lot of pigs fed the same
ration without pasture gained 1.22 pounds daily and required 409.03
pounds of feed for every 100 pounds' gain. Pasture not only effected a
saving of over 40 pounds of concentrates for each 100 pounds' gain, but
also made the gains more rapid.

The results of fattening pigs on a ration of rolled barley, chopped
alfalfa hay, salt, calcium carbonate, and pasture, composed entirely of
home-grown feeds, except for the inexpensive salt and lime, should be
of interest to California producers. This diet has a wide nutritive ratio
and a higher fiber content than most rations fed to fattening pigs; but
its energy, mineral, and vitamin content are adequate. Pigs (49 head)
thus fed gained on an average 1.27 pounds daily and consumed only
406.51 pounds of concentrates (barley, alfalfa hay, salt, and lime) for
each 100 pounds gained.

The data on the fall and spring pigs, of the lots that are comparable,

6 Hughes, E. H. Vitamin A content of barley. Jour. Agr. Besearch 47:487-494
1933.

7 Bohstedt, G. Mineral and vitamin requirements of pigs. Ohio Agr. Exp. Sta.
Bui. 395:146-158. 1926.

16 University of California — Experiment Station

show very little difference in the rate of gain of the young pigs, or of
those that were fattening. The fall pigs fed during the fall, winter, and
spring of 1932 and 1933 required more feed per unit of gain than the
spring pigs fed during the spring, summer, and fall of 1933. The fall
pigs in lots 1, 2, and 3 of experiment 1A, required nearly 14 pounds
more feed for 100 pounds of gain than the spring pigs in comparable
lots. During fattening, the fall pigs in experiment IB, consumed nearly
45 pounds more than the spring pigs (experiment 2) for 100 pounds of
gain, although the same rations were fed. The climate of the fall of 1932
and the winter and spring of 1933 was average for the Sacramento
Valley. The summer and early fall of 1933 were warmer than usual. Two
factors probably caused the difference in food consumption for a unit
of increase. First, basal metabolism was increased, because of the low
temperature and high humidity during the winter months, so that more
feed was required for 100 pounds of gain. This extra feed was utilized in
keeping the animals warm. Second, the feeds used were analyzed during
warm weather. Throughout the winter months, with a higher humidity,
they doubtless took up moisture. Increased feed consumption per unit
of gain would therefore appear because of a lower percentage of dry
matter in the rations in the late fall and winter months.

SUMMARY
Under the conditions reported herein, young growing and fattening
pigs with access to pasture, gained more rapidly than did similar pigs
in dry lot. This observation agrees with the findings of other experiment
station workers.

The evidence presented suggests that the vitamin A contained in the
forage was an important factor responsible for greater gains by those
animals having access to pasture.

Under the conditions of these studies pigs having access to pasture
from weaning time to a weight of 75 pounds gained more rapidly, when
fed in dry lot, during the fattening period than those not receiving green
forage during their early life.

In these experiments, pigs fed during the summer and early fall
required less feed per unit of increase than similar ones fed through the
late fall and winter months.

Young pigs weighing 30 to 75 pounds consumed less feed per unit of
gain than older hogs weighing 75 to 200 pounds. The heavy hogs, how-
ever, gained more rapidly than the smaller ones.

Thrifty, rapidly growing pigs were produced on locally grown feeds
and pasture containing the necessary nutrients and accessory factors.

16m-9,'34