2.1ibais
on
CALCIUM, 21-10SPHORUS AND VITAMIN D
NE:qUIMMENTS OF GROWING CHICKS,
Submitted to the
OREGON STATE', AGRICULTIMAL COLLEGE;
.101.11111111011.~1.11
ANNIONIONIMINIMMINIOD
11111.11011111.01110
In partial fulfillment of
the requirements for the
Degree of
MASILR
SCIBNCE
by
Walter Knowlton Hall, 3.S.
May 1933.
APPEOVLD:
Signature redacted for privacy.
Profe eor o Agricultural Chemistry*
Signature redacted for privacy.
tild
of Department of Ghemistry
i)
Signature redacted for privacy.
Chairman of Committee on Graduate Study*
Acknowledgement
These studies were conducted as a part of a cooperative project between the Departments of Agricultural
Chemistry, Poultry Husbandry and Veterinary Medicine
and were made possible by a research fellowship created
by the F.C. Booth Co., Inc., San Francisco, California.
The experiments reported were conduoted under the immed-
late supervision of Dr. J.E. Haag, Nutrition Chemist of
the Agricultural Experiment Station. The writer wishes
to acknowledge his appreciation of the assistance and
many helpful suggestions rec ived from him, and from
other members of the above departments.
TABLE OF CONTENTS
?age
INTRODUCTION
HIsTORICAL
1
The Physiological Action of Electrolytes on Organisms and Excised Tissue
1
Sodium and Potassium
2
CEllcium and Magnesium
3
Calcium and Phosphorus Reletionships
Calcium and Phosphorus Metabolism in
Poultry
4
6
THE; psomism
12
GENERAL PROCEDIM
13
EXPERIMENTAL METHODS AND DATA
13
DISCUSSION
25
SUMARY AND CONCLUSIONS
29
BIBLIOGRAPHY
31
CALCIUM, PHOSPHORUS AND VITAMIN D
RE4UIRLIC6NTS OF GROWING CHICKS.
INTRODUCTION
The problems involved in the determination of the
calcium, phosphorus and vitamin D requirements of grow.
ing chicks are much more complex than was commonly sup-
Posed to be the case only a few :pears ago. As a result
of studies in the field of pure physiology, and of rick.
eta in experimental and farm animals, we have come to
recognize the existence of important but more or less ob.
scure interrelationships between calcium, phosphorus and
vitamin D requirements. In recent years considerable
importance has been attached to the significance of Ca/P
ratios in the nutrition of experimental and domesticated
animals, and of poultry in particular. Because of the
interest in such ratios, and because of the importance
of a proper understanding of the principles involved the
writer wishes first to review briefly some of the work
leading to the development of the idea that a more or
less balanced condition among the mineral salts in the
diet is essential to normal nutrition.
HISTORICAL
The ?hYsiological Action of :alectrolytes on Organisms
and Lxcised Tissue, The concept of a physiologically billsnood condition among the mineral ions occuring in the
normal environment of living organisms is largely the results of studies first conducted in the field of what may
be called pure physiology.
Nesse in 1869 (see Sollman 1924) determined the isosmotic concentration of pure sodium chloride solutions
for frog tissues. Such isotonic solutions, known as nor-
mal saline solutions are still used for blood dilution
or histological examination of tissues. Ringer (13801882, 1882-1883 , 1882-1883, 133C) found such solutions
unsatisfactory for the maintanace of the normal reac.
tivity of frogb muscles or of the beat of a perfused
frog's heart unless there was a balancing of the physiological action of sodium ions by potassium and calcium ions.
Herbst in 1897 (wee Needham 1931) showed that sea urchin
larvae needed all tbe constituents of sea water for normal
development. Previous to 1900 these inorganic ions were
thought of merely as nutrients. In 1900 Loeb (Loeb 1916)
stated his now well known theory of physiologically balanced salt solutions which he had formulated from the results of his extensive experiments. Loeb's statement
was as follows: "-----the theory of physiologically balanced salt solutions b which we mean that in the ocean
-2-
(and in the blood or lymph) the salts exist in such ratio
that thsy mutually antagonize the action which one or
several of them muld have if they were alone in solution."
As may be seen from this statement of Loeb's, the counterbalancing of the physiological effects of various ions
or croups of ions, are often spoken of as "antagonism."
The conception of physiologically balanced salt
solutions has received additional support as the result
of the in,Y,ction of various salts (Robertson 1920,
nett 1903, Haag 1926, Sjollema 3ickles and Van der Kaay/32
Sollman 1924) into the circulation of higher animals and
has been resorted to (Sollman 1924, iobertson 1920 7ive
reviews) in an attempt to explain the cathartic action of
saline purgatives.
Thera aro also nunerous facts and experiments in the
field of human and animal nutrition which have variously
been thought of as involving the phenomena of ion antagonism, a few of the more important of which will be
cited below.
Sodium and Potassium. 8ungets (1902) work on salt
craving appears to be the first important study of what
might now be looked upon as a case of ion antagonism in
animal nutrition. He thought it remarkable that of all
the salts in the diet, herbivores craved only sodium
chloride. Herbivores take three to four times as much
.3.
potassium in the diet as carnivores which experience no
such craving. This led 6unge to cilieve that the salt
craving was due to the high potassium intake He found
that eating of potassium. salts caused an increased excretion of sodium which led to salt hunger. He cites an
enormous amount of evidence in support of his theory. The
findings of a number of investigators have not entirely
supported 3unRets theory, Miller (1923, 1923a, 1926)
interprets his findings from the feeding of rats and
pigs as not entirely in support of 3unge's theory, The
conclusion of Hart, McCollum, Steenbock and Humphrey
(1911) and of Harrar (1925) are not in accord with !lunge
theory. However Gerrard (see Haag 926) interprets his
experiments with dogs as favoring Bungels theory.
Sherman (1932) expressed what is perhaps the best
summary of present day opinions by saying of 3ungels theory,
"While :3-tinge's explanation may not be entirely adequate in
detail, there seems to :A3 little doubt as to the correct.
ness of his main deduction."
Calcium and Mag,nesium. Magnesium salts whether in.
jected into the body or taken orally, tend to cause a
loss of calcium from the body (Haag and Palmer 1923,
Mendel and iz,enedict 1909, Forbes et al, 1922, 1924, Bogert
The harmful effects of excessive
amounts of magnesium in the diet are said to be alleviated
and McKittrick 1923),
-4-
in part at least, by the presence of liberal amounts of
calcium and phosphorus (Hart and Steenbock 1911, 1913,
Haag and Palmer 1928), Other investigaters place lass
emphasis on the harmful effects of magnesium in ordinary
diets (Hart,. Steenbock and Morrison 1917, Elmsbie and
Steenbook 1929, Medea .926, Huffman at al. 1930). Moriquand (1931) found that the ingestion of mapelesium carbon-
ate intensified rickets. euckener, Martin and lnsko (1932),
Mussehl at al. (1930), the Idaho-.experiment Station (1929),
Wheeler (1919) found either an intensification of rickets
or a serious disturbance of calcium and phospiorus metabolism when hi h levels of maencsinm were fed to chickens.
eelcium and eeospeorus ielationshiat The importance
of Ca patios has become increasingly apparent since the
interrelation of the inorganic nutritionally essential
elements was first emphasized by some of the earlier workers (McCollum and Davis 1915, Osborne and Mendel 1918).
McCollum et al. (1921) found that diets containing an
amount of phosphorus which Sherman and Papenheimer (1921)
had shown would prevent rickets, became rickets-producing.
when enough calcium was added to raise the Ca/P ratio to
approximately 4.0. As a result of this work it has been a
common practice to use high calcium-low phosphorus diets
in the production of experimental rickets. Meigs, Turner
and associetes (1926) have expressed the opinion that a
Ca/P of 2.0 is unnecessarily high for cows. Hart and
Steenboek (1930) were of the opinion that for milking
cows, a ratio of 1.3 was optimum. Lindsey, Archibald
and Nelson (1931) found that for all ages of cattle, a
Ca/P ratio of 2.0 was satisfactory. According to Reimer
and Smuts (1932) a Ca/P ratio of between 1.4 and 1.2 ap.
peared not far fram optimum for pigs, aethke and co-workera (1930) report that within certain Anita Ca/P ratios
are more important than the concentration of these elements
in the rations, and that wide Ca/P ratios increase the vitamin D roquirements. In a later paper Bethke et al. (1932)
again emphasize the impo..tance of Ca/P ratios. As a result of a quite comprehensive stud, a Ca/P ratio between
1 and 2 was found to iv the optimum ratio for rats. A
short nota in trk Annual Report of the Wisconsin Agricultural axperiment Station (1928-29) suggests 1.5 as the
.accepted Ca/P ratio for neaunals. Kramer and Howland (1932)
claim that in Mao absence of vitamin rig the Ca/P ratio of
the diet Jo reflected in the blood of an animal, isrown,
Shohl and collaborators (1932) state that "...Both the
level and ratio of calcium to phosphorus are necessary to
-characterize adequately the ricketogenic properties of a
diet.
It therefore appears that in the prevention or production of rickets,' at least fourfkotors must be considered, These are the levels of calcium, phosphorus, vitamin D
.6.
(or its equivalent) and the Ca/P ratio. In addition, the
acid-base balance of the diet and the magnesium level may
at times rsquire some cansideration.
Calcium and Phosphorus Metabolism in Poultry. In-
tensive studies of the calcium and phosphorus roquirs.
ments of poultry have been made since the discovery (Hart,
Halpin and Steenbock 1922) that nutritional leg weakness is
to be regarded as analagous to rickets in other animals.
Mails these studies have made possible the practical elvrina_
tion of such disorders, they have also helped to emphasize that Calcium and phosphorus nutrition is conditioned
by a number of complicating factors.
Hart, Halpin and Steenbock (1922) demonstrated that
leg weakness in chickens could be prevented b7 feeding
cod liver oil. This has been abundantly corroborated by
subsequent investigations (Dunn 1924, Plimmer, Rosedale
and Ra7mond 1925) and practical experience.
A number of fish oils other than cod liver oil have
been shown to he effective carriers of vitamin D. Since
cod liver oil has been used no widely, it is often used
as a standard of comparison for other fish oils. Bills
(1927) found sardine (pilchard) similar to cod liver oil
in vitamin D content. Nelson and Manning (1930), Gutter.
idge (1932, 1932a), Halvorson and Lachat (1932, 1932a)
Truesdell and Culbertson (1933) have confirmed Bill's
results. Asmundson et al. (1929) found sardine oil inferior to cod liver oil for bone calcification of chickens.
Since the various studies cited above have shown that crude
unassayed sardine oil is subject to the same variation
in vitamin D content as is crude cod liver oil, this dis.
creptancy probably may be explained in that way. Sur
bot oil and tuna fish oil have also been shown to be
similar to cod liver oil with respect to their vitamin D
content (Halvorson and Lachat 1932, Truesdail and Culbert.
son 1933). Dog fish liver oil seems to be inferior to cod
liver oil,
(Halvorson and Lachat 1932).
Good salmon oil
Is also equal to good cod liver oil (ielliot and eelson et
al. 1932, Tolle and Nelson 1931).
Irradiated ergosterol ('Viosterol") is not well util.
ized as a source of vitamin D by poultry as it takes from
forty to one hundred and twenty times as many rat units
in this form as in the form of fish oils to prevent rickets
and produce normal erowth,(Journal of the American Medical
Association, :Editorial, 1932, Masqe;ngill and Nussmeier 190,
Hall et al. 1931, Steenbock ot al. 1932, Mussehl and Acker.
son 1930, Russel and Klein 1931, King and hall 1931). The
Inability of chicks to efficiently utilize irradiated
ergosterol has not yet been satisfactorily explained,
Vitamin D may be produced in the chicken by exposre to ultraviolet irradiations or sunlight. 6unlight seems
to be moreeffective than artificial ultra violet irradia.
.8.
tion, possibly due to the physiological action of rays
outside the ultra violet region. (Mussehl 1932, 1'2,1:usseh3.
1932 Bethke
Kennsrl and Kick et al. 1929, l'.:1111er Dutcher and Knandel
and Ackerson 1931, 7,,la7erson and Lawrence
3.929),
the common practice has been to re commend some
to 2 of a potent cod liver oil (or its equivalent)
in the rations of crowing chicks (Fox 3.931, Journal of the
American Medical Association, Lditorial 1932, Dunn 1924),
recent experirtenta indicate that under favorable oonditions
such a recommendation may be regarded as quite liberal
3.
(Plirrer ibsedale and ":fx:Trionel 1:)25 Dunn 1924, Gutteridge
1932, Grimm 1932, Halvorson p,nd Lachat 19321, Since It
is nor known that the apparent vitamin D requireMent of
chickens is dapendent upon the levels of calcium and phos
phorus, the Ca/P intake ratio, the 'rate of groT,Tth, and per-
haps other factors, it is easy to understand why different
investizators have obtained variable results with the lar-e
variety of exlnrimental conditions and '.)asal rations used
in such experiments.
in addi ti on to the rachitic le g we akne as due to unfavorable levels of calcium, phosphorus and vitamin D,
there are a number of other leg disorders which 9re not
of a rachitic character, 3ethke and Record (1933) have
classified the various chick disorders as follows:-
Rickets or true leg weakness due to disturbance of
calcium* phosphorus and vitamin D metabolism.
Hock disease, slipped tendon or perosis thought to be
duo to an excess of minerals combined with rapid growth.
Ground whole oats or rice bran appear to possess preventa.
tive properties.
Crazy chidkw bich shows symptoms similar to but appears
not to be identical with those resulting from vitamin
defficiency.
Nutritional paralysis which appears to be asaociuted
with a deficienoy of the vitamin G complex.
6. Ein or fowl paralysis, the nature of which is not
known.
The minimum, optimum and maximum levels of calcium
and phosphorus and the optimum Ca/P ratios recommended by
different workers vary considerably. These variations may
perhaps for the large part be explained by differences
in the rate of growth obtained, the vitamin D content of
the basal rations used, and the frequent attempts to draw
sweepinf, conclusions from experiments limited to a few
weeks duration. A number of investigators have expressed
the opinion that the minimum calcium requirement for growing chicks is about 0.60 and minimum phosphorus, about
0.50 to 0.60 (Wilgus 1931, Tullf,Hauge, Carrick and Rohe
erts 1931* Hart ot al. 1930, Dunn 1924, Cornell 4,xporiment
-10-
Station 13ul1etin 1930), Hart et al. (1930) and tiv Ohio
Experiment Station Annual Report (1920) have suggested 2.0
and 2.5 respectively as thia minimum calcium level, The
Cornell Station Annual Report (1930) caves the optimum
calcium and phosphorus levels as being between 1.0 and 1.2
for calcium and between 0.80 and 0.90 for phosphorus.
Blish and Ackerson (1927) found that 3,02 calcium and 2.15
phosphorus gave good growth but that higher levels WVO
poorer growth. These levels sire probably near a maximum.
Wilgus (1931) reported that 1.2 calcium and 0.50 phosphorus ally° good growths.
For some time it has been commonly assumed that in
mammalian nutrItion the optimum Ca/P intake ratio was of
the order of 1.5 to 2,0 (5stbke at al. 1932
Annual Re-
port, Wisconsin Agricultural .w.z.priment Station 1928-29,
Meigs, Turner at al. 1926, Hart and Steenbock 1930,
Lindsey, Archibald, and Nelson 1931, Reimer and Smuts
1932). Hart, Scott, Kline and Halpin (1930) reported the
optimum Ca/P ratio to probably be between 2 or 3 and 4 and
Bethke at al. (1929) report/3d it to 1-e between 3 and 4.
It will be noted that these ratios are much higher than
those convonly accepted as normal for mammalsiand it should
be pointed out that these investigators used basal rations
which camot be regarded as containing optimum amounts of
vitamins 1), Bart et al. (1930) also observed that an ample
-11-
supply of vitamin D enabled chicks to tolerate wider variations in Ca/P ratios than when the sipply of vitamin D was
at or below the minimum. A number of investigators have
suggested a Ca/P ratio of between 1 and 2 to be better
than higher ratios (Cornell Lxperiment Station 1932, Park
burst and McMurray.1932, Musseba Blish and Ackerson 1927,
Holmes and ?j got 1931, Wilgus 1931, Wisconsin Arricultural
k,xperiment Station 1928-29).' In discussing optimum Ca/P
ratios it is too often assumed that the optimum Ca/P
ratio is a more or less fixed quantity. This is not
necessarily the case. It has been shown by Sherman and
4uinn (1926) and by Haag and Palmer (1928) that young
rats of a certain age store about 1.2 times as much calcium as phosphorus, where, as for older rats, this figure
more nearly approaches 2.0. In the case of Chickens, it
is entirely possible that the optimum Ca/P ratios for different stages of rrowth and for egg production may be entirely
different,
-12THE PROBLEM
As trill be wen from the forgoing literature review,
the calcium, phosphorus, and vitamin D requrentents of poul.
try are closely interrelated and these interrelationships
are not as well understood as might be desired. It is not
surprising, thezvfore to find a considerable lack of agree.
merit among various investigators as to the exact calcium,
phosphorus, and vitamin 1) requirements, This lack of agree.
!tient may be explained in terms of a number of interrelated
factors. Attempts to cletermin-,:: tla,3 vitamin 0 requirement
of f'7rowinq chicks have yielded variable results because, as
is now knows Vas vitant.n i) requirement is influenced by the
rate of t7rowth, trv levels of calcium and of phosphorus and
by the Ca/P ratio, The optimum lsvels of calcium and phoshorus are likewise conditioned b7 the suppl7 of vitsrlin D
(or its equivalent). In ad ition to the above factors, there
Is the frequent failure to give proper consideration to the
experimental conditions necessar-: to demonstrate the exact
simifieance of Ca/P ratios,
Tie considerations enurnrated above are not only of
theoretical interest to the nutrition specialist, but of
great practical importance to the poultry industry, This
is especially a r. parent when 713 consider the modern inten-
sive manngernent practices in conjunction with the fact
that excesses of calcium and phosphorus are known to be
detrimental, and that such excesses are apparently net
far removed from the optimum
PROMDUit.
The etperi.ental work described in the following pages
was outlined with the following considerations in mind:
The clloice of basal rations that would moduce an excellent rate of growth under practical conditions.
A study of such levels of °aid.= and phosphorus as
might be presumed to come within the range of optimum
nutrition under practical conditions.
Z.
A study of vitaTran D requirements exid the evaluation
of the vitamin D bearing oils used in the experimental
rations.
LXII.RIKENTAL keTHO.D5 AND DATA
Three different groups of day old single combed white
legborn chicks (700 in all) were used in these experiments, These were kept indoors in battery brooders in the
absence of direct sunlight« They were weighed weekly.
The chicks were usually divided into lots of twentyi ex-
cept for a few of the oil testing lots.
The composition of the rations used is given in
tables I and II. The rations were of two types. Numbers
147 inclusive were various modifications of the"O.S.A.C«
No. I Milk Nash" formula given in 0.5.A.C. Extension Bulletin 435. In general these modifications dealt with the
amounts of bone meal and oyster-shell flour added to these
rations. Rations 26-29 were also practical rations which
contained less calcium than the "O.S.A.C. no I. Milk Mash"
.14and were made from ingredients obtained from a different
source. Rations 19.26 inclusive were based on the rachit
lc ration developed by the Wisconsin workers. (Hart,Klins
and Keenan 1931). hation and lot numbers are identical
throughout, i.e. ration number 1 was fed to lot number 1.
The cod liver oil used in these experiments was ob.
tamed from a mixed batci of unrefined medicinal cod liver
oil. The sardine oil Was purchased in the ratan markets.
The other ingredients were comnercial products of good
quality.
The feeds were analyzed with the results shown in
Table III. Moisture, ash, crude protein, crude fat and
crude fiber were determined by the A.0.11,C, Method. Calcium was determined by precipitation as the oxalate and
titration with potassium permanganate The oxalate was
precipitated (in the presence of ammonium chloride) from
a solution made red to methyl rod with acetic acid. Phosphorus was precipitated as (NH4)3 4 12 Mo03 and the
yellow precipitate titrated by Fern
Tnetind.
nts alkalimetric
-15Table I.
This table shows the formulas forrations 1,9,10,19
and 30 as fed. Rations 2 to 8 inclusive were made up from
No. 1 as shown in Table fl Rations 11 to 17 inclusive
were made up from "Basal ffier 11.17" as shown in Table II.
Rations 20 to 25 inclusive were rade up from ration No. 19
as shown in Table II. Rations 31 to 33 inclusive were made
up from N. 30 as shown in Table
3a Sal
Nolte Illation
...M11.on_ No.
1
9
10
11-17
19
30
590
400
Yellow Corn
400
400 400
400
Wheat
100
100 100
100
100
Oats
100
100 100
100
100
120
120 120
120
120
Mill
in
Meat Meal
50
50
50
50
Special Low An Meat Meal 50
Fish Meal
Dried Skim Milk
50
50
50
50
50
75
75
75
75
76
Alfalfa Leaf Meal
40
40
40
40
40
5
5
5
5
Sodium Chloride
Ground Oyster Shell
25 10
Precipitated Calcium Carbonate
bone Meal
10
5
25
10
25
26
Precipitated Tri-Calcium Phosphate
5
God Liver Oil
10 10
10
Standard Wheat Middlings
250
Casein
120
10
ta
945 980 960
940
1000
990
-16-
Table II
This table shows the manner in lihich the various rations were compounded from tik basal rations described in
Table I.
=====:
1
Rati,Dns No.
L:,asal for 1-8
3.00
122=111
.
L
2
99.5 99.0
93.0
1.0
2.0
99,0
913.0
97.0
97,0
Cod Liver Oil
Bono Neal
100
0* star '614 1
11
Ration Ne-
Basal for 11-17
Cod Liver 011
Bone Meal
0,.ster Shell
mos*.
Ration No,
12
13
1.0
2.0
3.0
20
14
15
16
.17
98.5 96.75 96.50 96.00 96.50 94,50
0.5 1.5 0.25 0.50 1.0 0.50 0.50
2.00 2.50
99,5
10
20
30
30
21
22
30
1.002.50
4.========
24
23
25
Basel for 19-25 100 99,875 99,75 99,5 :)9.6759.75 99.50
0.125 0.25 0,5
Cod Liver Oil
0
Sard1ne_011
Ration No.
Basal for 26-2'4*
Sardine Oil
Cod Liver Oil
====t-mh.._
Ration No.
Basal for 30.33
Sardine 011
26
100
27
28
29
99,75 99.50 99.75
0.25
0.50
0.25
_j2p
31
32
33
100 99.875 99.75 99.50
0.125
*Rations 26 and 30 were made up without any oil.
0.25 0.50
Tilble III
Chemical Analyses of Rations
Ration Mois. Ash
ture
No
Ca
Ca
Nx6.25
2
10.93 4.37 0.64 0.66 1.0 18.75
11.45 4.35 0.67 0.67 1,0
3
11.60
4
11.31 5,66 1.13 0,87
10.86 5.17 1.02 0.66
1
5
7
8
9
10
11
12
13
14
15
16
17
19
26
30*
5.48 1.43 0.66
10.30 6.17 1.75 0.65
10.75 6.28 1.63 0.75
10.75 8.06 2.60 1.03
10.07 5.95 1.52 0.85
10.23 5.23 0.86 0.74
10.06 5.83 1,25 0.73
9.83 7.19 2.07 0.72
9.90 7.00 2.09 0.72
10.23 7,27 2.12 0.70
9.89 7.20 1,78 0.95
9.50 8.36 2.43 1.00
11.32 4.57 0.79 0,66
10.13 7,70 2.16 1005
011 00 WI
410111111111111111001i=111141111111111111111101111
5.12
Fiber
3.30
5,48
5.08 0.88 0,77 1.1
10.81
6
fat
WOOM
WIMP4mh
Woo.*
1.3
1.5
2.2
2.7
2.2
2.5
4.96
3.60
1.2 18.96
1.7
2.9
2.9
3.0
1.9
2.4
1.2 19.34
4.52
4.97
4,44
4.39
5.45
3.95
2.1
15.40
3.94
4.66
WOOVIN
0.000M
41001...
411WOOM
18
4.94
5.09
2.16
* Ration No. 30 as 3iri1ftr to R-,,tions 9 and 17, except for
oil levels.
-18-
The chickse were bled from the heart and the total
calciun enc1 inerefe-lic eboseheres of the blood serum were
t1::
are :elven in table VII,
n.
i e i
4bL
c 117 s
ro,iment, the chicks were
killed en1.1 the lee, bones eeeoeed, he right tibia tyas
exaelined eeistoleeicalle aria than crushes, dried, extracted
with hot alcohol aree then eith ether, The bones were then
ashed for eix hours at 7000 C. and the ash expressed on
the dry t free basis.
For lots 19-25 (start,ed. ene. 6) the right tibias were
lashed individually an the resats averaged. For each of
theee lote, totel nointuee and fat free bone weights were
divided b":.7 total e sh woiehts ehe results of these eelculee see e
de te
ations re re co re d. -with the evorages of individual ash
percentages, e coeperieen was thus obtained between the
results ee ineivieuel eshine an' the results which would
have beee eete. 1. Teel if !r1.11 the beees of each lot had been
grow-el,
eel() e !lee
ee pre se nte tive sari ple a 81-..,e
The cliff -
erenceci eetween the tee metheis vere not sienificant
showia in table I; I, The ma tho of .eroup lashing by the lot
was useee for al 1 other :cieht tibia ashines,
vibe eri ter wishes to cern() rae dee his in de bte dne s s to
Johnec,e, eoultre Petheleeist, Aeric71.1tural e;xper-
iment :jeation, Orton Stet eolloee, for his service in
bite ding the ceicks from the rt rt and for examinine them
for abnormalitieS
.19.
Table IV
Chick weights (grams) and 7!orta1ity. "Average" weights at
5-13 weeks 10 Amtml4LIT9,9_221Anct 4 average female weight.
2
allIO4r.em
Lot ito. No
t
"Orig.Av
CI-11 cks
thai
t
1117.IA.
Av.Yrt..
AvOt
-----"r--Zr-,
34.65 552
530
1
20
4
2
20
3
3
20
4
4
20
2
5
20
6
a,
34.55 346
34.55 357
7:757-rff wks. 13 wks.
964
1060
518
927
1034
640
980
1093
528
933
1045
3
34.2 548
34.55 352
547
932
1042
20
5
34.20 356
505
927
1052
7
20
2
34.65 338
490
897
1017
8
20
8
653
954
1083
9
20
4
34.40 361
34.45 409
623
1051
1171
10
19
1
31.00
555
957
1049
350
32,6 413
727
12
21
4
33.0 468
791
13
21
4
33.6 427
711
4
14
21
32.1 427
731
15
21
0
32.4 412
725
16
3.
21
32.6 416
730
17
21
33.8 404
726
* The relatively high mo rtali ty is lk rm. 1 y due to deaths
rs sui ting from taking bloc d sun pie s from the art.
11
21
3
Table IV continued
No. of
chicks
Lot No.
19 (Started June 10)
oria1-3rity
12
0
20
ft
ft
11
0
21
ft
ft
11
1
22
n
ft
11
0
11
0
11
0
11
1
20
1
23
24
ft
25
n
ft
19 (Started Aug. 6)
21
ft
It
20
0
22
ft
ft
20
1
24
It
ft
20
0
If
If
20
0
26
12
0
2'7
10
2
28
10
0
29
10
1
30
20
3
31
20
32
33
25
ft
wt
w s.
33.4
35.2
145
32.8
32.5
34.0
32.8
32.5
33.7
35.6
33.5
33.8
33.8
193
34.2
32.5
32.6
192
270
161
274
330
174
231
260
232
269
8 wks.
502
559
589
588
1
33.4
33.8
33.9
531
648
20
2
34.0
503
618
20
2
34.0
639
755
512
9 wks.
623
.21.
Table V.
Bone data obtained from right tibiae.
Lot No.
Age in
;4) Ash*
emarks
weeks
1
13
2
13
48.8
50.1
3
13
50.6
4
13
52.4
5
13
50.5
6
13
7
13
51.4
51.9
8
13
9
13
10
13
11
9
12
9
13
9
14
9
18
9
16
9
17
9
52.2
53.3
53.4
52.6
Approx. 30% slipped tendons.
49.8
47.2
49.5
50.6
50.1
50.6
*The "% ash" figures given in Table V were obtained from
composite samplas prepared from the right tibiae.
4.22.
Table VI
Bone data obtained from right tibiae
Age in % Ash % Ash (Av. of
weeks (Composite Individual
Lot No,
Sample)
Remarks
bork,$)
19 (June 10) 5
31.1
all rachitic
6 rachitic
3 rachitio
0 rachitic
9 rachitic
3 rachitio
0 rachitio
20
ft
5
35.9
21
ft
5
40.8
22
5
44.9
23
5
34.3
5
40.1
25
5
19 (Aug.6)
5
24
ft
21
tt
5
45.6
(50.7)
(39.4)
22
a
5
(43.3)
5
(3864)
5
(42.9)
42.5
48.3
48.3
48.0
24
25
a
26
8
27
8
28
8
29
8
30
9
31
9
42.7
46.5
32
9
47.4
9
49.6
50.6
all rachitio
39.2
43.3
?!. rachitio
38.0
42.8
Normal
13 out of 20 rachitic
1 out of 20 rachitic
1 rachitio
0 rachitic
0 rachitic
0 rachitic
all rachitio
7 out of 19 rachitic
14 normal: question
about 4
Normal
-23Table VI continued
The it% ash" values given in table VI are of 3 types.
The firruzes in the third column, not in parentheses, were
obtained by ogling composite samples. Those in the fourth
column are group averawes obtained by averaging the ash
content of individual bones. Those in parentheses in the
third column are calculated to the composite basis from the
data obtained from the individual bones, %marks on lots
25 (June 10) and lots 26 - 29 are based on appear19
ance of chicks during 5th week. Remarks on other lots are
based on examination of tibiae.
-24Table VII
Blood analyses based on composite samples drawn from heart.
Analyses are expressed in mm., pr 100 cc, of serum.
Age of chicks
Lot No.
w
mon,
Days
Inorganic
Calcium
sartWa_j2,)j)d
or 100 cc
9.72
Phosphorus
Infrn1
per 100 cc.
1
51.554.69.90
2
ft
tt
It
tt
9.79
7.16
7.28
3
It
ft
ft
If
10.01
6.29
4
tt
ft
ft
It
10.41
5
If
II
It
If
10.48
tt
ft
tt
10.27
7.38
6.69
6.48
5.16
6.51
6.46
6.66
6.12
6.18
6.81
6.68
6.67
6
7
ft
ft
ft
II
10.40
8
11
It
tt
It
10.23
9
It
ft
n
ft
10.23
10
11
ft
ft
II
ft
10.37
68
12
ft
13
ft
14
ft
15
ft
16
ft
17
ft
30
66
31
ft
32
33
ts
9.79
9.58
11.99
12.58
7.27
7.17
6.18
7.81
7.43
7.34
.25.
The rate of growth obtained in these experiments was
comparable to that obtained in actual practice. The r,rowth
and mortality records are summarized in table Iv. The
weights are given at ages which allow comparison with other
studies. The somewhat more rapid growth of lots 9 and 10
over lots 1 - 8 inclusive was probably due to the superior
quality protein of the meat meal used in rations 9 and 10.
The apparently high mortality in some groups is largely
due to deaths resulting from the taking of blood samples
from the heart for analysis. There were no indications
that nutritional factors wore involved in mortality rates.
Tables V and VI contain a summary of the ash of the
right tibia, results of the histological examination of the
bone and comments based on anexamination of the chickens.
DISCUSSION
In romnal, satisfactory growth was obtained throughout the experiment on all the practical rations. This is
of considerable significance because some of the variable
conclusions arrived at by some other investigators are un.
doubtedly influenced b7 the relatively poor growth ob.
tamed under certain experimental conditions, It may be
assumed that the requirements for at least certain nutrients
are considerably areater where rapid arowth is obtained.
Our results should therefore have some application in
actual practice.
.26.
A summary of the more important data is given in
Table VIII.
In general the growth, blood analyses and bone ash
data do not favor either the higher calcium and phosphorus levels or higher Ca/P ratios. The calcium and
phorus levels of lots 9 and 17 may be consider, d as being
near the maximum for these elements since slipped tendons
were produced in lot 9. There is some indication thatthe
Ca/P ratio of lot 7 was exceesive.in view of the slightly
slower rate of growth and the continued lower level of
inorganic blood phosphorus.
Tho good growth of the
chickens on all of the lower cab? ratios does not indicate
that the optimum Ga/P ratio for chicks is vastly different
lower bone ash for
lots one and two would seem to indicate that the calcium
and phosphorus levels of these rations were approaching a
than that for mammals. The all
In lots 1.17
the higher mineral levels seemed to give slightly higher
minimum, although rood growth was obtained.
bone ash figures.
The particular lots of sardine and medicinal cod
liver oil used in those experiments seemed to be approximately equal in anti rachitic potenc-, as shown by the
bone ash figures for lots 19 to 25 inclusive. The lower
vitamin levels in lots 30 and 31 may have caused a slight
depression in the blood calcium of these lots.
-27-
Table VIII
Summary from Tables 1-VI.
Lot
No.
1
Vitamin D
Ca
6earing oils Ca
.5:* C.L.0.. .64
1)
P
.66
1.0
"Average"
reirtht
(7ra7s)
13 wk.
bone
ash
1060
13 was.
48.8
n
ty
ft
.67
.67
1.0
1034
50,1
3
.52% "
ft
ft
.88
.77
1.1
1093
50,6
4
.52% " "
tt
1.13
.87
1.3
1045
52.4
5
.52% "
tt
IT
1.02
.66
1.5
1042
50.5
6
.52% "
ti n
1,43
.66
2.2
1052
51.4
7
.51% "
It
n
1.75
.65
2.7
1017
51.9
8
.51% " n
n
1.63
.75
2.2
1083
52.2
2
1.03%
9
1,02% "
ft
n
2.60 1.03 2.5
1171
53.3
10
1.04% "
fl
n
1.52
1.8
1049
53.4
.85
1,2
729
9 reeks
52.6
1.25
.73 1.7
791
49.8
II
2,07
.72
2.9
711
47.2
ft
ii
2.09
.72
2.9
731
49.5
II
ft
2.12
.70
3.0
725
50.6
16
.50% " " 0
1.78
.95
1.9
730
50.1
17
.50% "
2,43 1.00 2.4
723
50.6
1110111.01.10111............101111.0...apoomeMMONO.....1-
11
*50% "
II
.86
12
.50% " " "
13
.25% "
ft
14
.50%
ft
15
1.00% "
tt
tT
It
9 weeks
.74
Table VIII Continued
Lot, -ftamin
_0, aearing oils
Ca
2
'Average"
eight
(Grams)
o veeks
WeeKS
19
none
20
.125
C.1,4004,
192
31.1
35.9
21
.25
C.L.O.
193
40.8
22
.50
C.L.O.
270
44.9
23
.12b,b' S rdine oil
161
24
.25%
"
25
.50
H
19
none
21
.25% C0L.041
2.11
22
50% "
260
24
.25>, Sardine oil
25
.50%
.79
.66
1.2
145
ti
274
34.3
40.1
it
330
45.6
174
30.6
39.2
43.3
.79
.66
1,2
"
ft
232
269
8 wES
38.0
42.8
8 weeks
502
42.3
27
2.16 1.05 2.1
.25% Sardine oil
559
28
.50%
589
29
4,25
48.3
48.3
48.0
30
none
31
.l25;
26
none
32
33
.50%
"
588
C.L.O.
9 weag
oil
648
46.5
618
47.4
755
49.6
In view of the relatively large number of factors involved, it is not possible to state the exact requirement
for calcium and phosphorus. The following statements, how-
ever, appear justified:
These studies show that excellent growth can be obtained on levels of calcium and phosphorus considerably
lower than those commonly recommendad.
There is no evidence in these studies to indicate that
Ca/P ratios for growng chicks are essentially different
wth of other
from those considered optimum for the
animals.
These studies indicate that if prevailing recom nda
tions for calcium and phosphorus are to be mvieed, such
revision will probably favor lower, rather than higher
calcium and phosphorus levels.
SUMMARY AND CONCLUSIONS
1. 700 chicks were fed practical mad experimental rations
containing various levels of calcium, phosphorus and vitamin
D.
The medicinal mid liver oil stock and sardine oil used
were shown to ha Na essentially equal antirachitic value.
3. Satisfactory levels of growth were obtained on all
practical rations used and results should therefore be
applicable to actual practice.
2,
Growth, blood analyses, and bone ash data in general
do not favor the high levels of calcium and phosphorus
or of Ca/P ratios often advocated.
5. The results obtained do riot indicate that the optimum
Ca/P intake ratio tbr growing chicks is vastly different
from that considered optimum for riannale
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