NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
136 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V, II
TABLE V.
Rhodes grass hay, all stages.
—
1st cut—
Hay . . .
NaCl and Water .
Total .
Faeces . . .
Urine . . .
Total .
Balance .
2nd cut—
Hay
.
.
.
NaCl and Water .
Total .
Faeces
.
.
.
Urine
.
.
.
Total .
Balance .
In grams per day.
Dry
matter.
4545.0
1743.1
9755 c.c.
4855.0
2219.6
6576 c.c.
P 2 O 5
20.25
..
20.25
14.49
1.44
15.93
4.32
11.30
..
11.30
11.12
0.12
11.24
0.06
CaO
26.75
1.37
28.12
18.70
0.12
18.82
9.30
20.50
1.35
21.85
18.11
3.29
21.40
0.45
MgO
13.94
0.58
14.52
7.86
2.24
10.10
4.42
8.28
0.58
8.86
5.16
3.04
8.20
0.66
Na 2 O
49.29
13.13
62.42
20.16
40.61
60.77
1.65
47.17
13.11
60.28
23.81
28.76
52.57
7.71
K 2 O
137.65
0.58
138.23
4.15
116.70
120.85
17.38
63.23
0.58
63.81
3.48
67.13
70.61
—6.80
PROGRESSIVE RIPENING OF FODDERS ON MINERAL NUTRITION OF CATTLE. 137
TABLE VI.
Aurangabad hay, all stages.
—
1st Cut—
Hay . . .
Cake . . .
NaCl and Water .
Total .
Faeces . . .
Urine . . .
Total .
Balance .
2nd cut—
Hay . . .
Cake . . .
NaCl and Water .
Total .
Faeces . . .
Urine
. . .
Total .
Balance .
3rd cut—
Hay . . .
Cake . . .
NaCl and Water .
Total .
Faeces . . .
Urine . . .
Total .
Balance .
In grams per day.
Dry
matter.
4720.1
256.1
2652.3
2993 c.c.
4603.8
257.3
2628.3
2050 c.c.
4774.4
347.2
2922.6
1433 c.c.
P 2 O 5
8.75
3.49
..
12.24
11.81
0.10
11.91
0.33
5.88
3.28
..
9.16
11.35
0.07
11.42
—2.26
2.33
4.54
..
6.87
10.21
0.06
10.27
—3.40
CaO
26.88
0.51
0.86
28.25
24.04
2.96
27.00
1.25
23.62
0.22
0.73
24.57
21.90
2.94
24.84
—0.27
26.24
0.88
0.76
27.88
22.48
5.76
28.24
—0.36
MgO
16.22
1.46
0.37
18.05
10.37
4.09
14.46
3.59
12.86
1.07
0.31
14.24
8.63
4.03
12.66
1.58
12.19
2.05
0.32
14.56
6.74
4.89
11.63
2.93
NaCl
10.87
0.73
13.26
24.86
11.59
1.37
12.96
11.90
13.31
0.90
13.01
27.22
10.71
1.32
12.03
15.19
18.76
1.34
13.06
33.16
11.75
1.18
12.93
20.23
K 2 O
31.55
3.81
0.37
35.73
5.68
43.70
49.38
—13.65
27.16
3.72
0.31
31.19
7.03
31.44
38.47
—7.28
10.95
4.91
0.32
16.18
9.64
10.91
20.55
—4.37
138
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V,
TABLE VII.
Spear grass hay, all stages.
——
1st cut—
Hay . . .
Cake . . .
NaCl and Water .
Total .
Faeces . . .
Urine . . .
Total .
Balance .
2nd cut—
Hay . . .
Cake . . .
NaCl and Water .
Total .
Faeces . . .
Urine . . .
Total .
Balance .
In grams per day.
Dry
matter.
4643.7
266.2
2268.8
5265 c.c.
4676.1
310.6
2674.1
2036 c.c.
P 2 O 5
14.53
3.62
..
18.15
15.23
0.10
15.33
2.82
6.94
4.06
..
11.00
12.10
0.07
12.17
—1.17
CaO
24.17
0.53
1.08
25.78
19.07
4.70
23.77
2.01
25.43
0.78
0.78
26.99
18.21
6.21
24.42
2.57
MgO
14.21
1.51
0.46
16.18
6.46
5.41
11.87
4.31
10.96
1.84
0.34
13.14
4.45
4.38
8.83
4.31
Na 2 O
13.98
0.76
13.67
28.41
11.72
..
11.72
16.69
11.87
1.20
13.12
26.19
11.56
1.55
13.11
13.08
K 2 O
58.67
3.96
0.46
63.09
11.02
50.49
61.51
1.58
16.46
4.39
0.34
21.19
7.83
10.06
17.89
3.30
PROGRESSIVE RIPENING OF FODDERS ON MINERAL NUTRITION OF CATTLE. 139
TABLE VIII.
Jouar hay, all stages.
—
1st Cut—
Hay
.
.
.
NaCl and Water .
Total .
Faeces . . .
Urine . . .
Total .
Balance .
2nd Cut—
Hay
.
.
.
Cake . . .
NaCl and Water .
Total .
Faeces . . .
Urine . . .
Total .
Balance .
3rd Cut —
Hay
.
.
.
Cake . . .
NaCl and water .
Total .
Faeces . . .
Urine . . .
Total .
Balance .
In grams per day.
Dry
matter.
4538.9
..
2058.9
6073 c.c.
..
..
4295.3
273.3
..
..
2338.2
4024 c.c.
..
..
4570.1
269.8
...
..
2446.1
4333 c.c.
..
P 2 O 5
24.64
..
24.64
22.29
0.25
22.54
2.10
20.20
3.48
..
23.68
23.61
0.20
23.81
—0.13
26.22
3.53
..
29.75
31.37
0.19
31.56
—1.81
CaO
17.34
1.27
18.61
14.92
1.01
15.93
2.68
13.05
0.22
1.17
14.44
13.81
1.82
15.63
—1.19
8.97
0.68
1.17
10.82
10.28
2.47
12.73
—1.91
MgO
20.23
0.55
20.78
14.29
3.39
17.68
3.10
13.90
1.14
0.50
15.54
10.91
3.00
13.91
1.63
12.60
1.59
0.50
14.69
10.02
3.96
13.98
0.71
Na 2 O
11.67
14.72
26.39
11.23
..
11.23
15.16
14.03
0.95
15.95
30.93
12.48
..
12.48
18.45
10.37
1.04
15.95
27.36
16.37
10.37
10.99
K 2 O.
154.00
0.55
154.55
20.42
130.63
151.05
3.50
94.16
3.96
0.50
98.62
22.76
76.08
98.84
—0.22
83.96
3.81
0.50
88.27
22.78
60.99
83.77
4.50
THE INFLUENCE OF PROGRESSIVE RIPENING OF
FODDERS ON THE MINERAL NUTRITION OF
CATTLE :—
PART II.—URINE CHARACTERISTICS AS INFLUENCED BY
PROGRESSIVE RIPENING OF FODDERS.
BY
N. KRISHNA AYYAR, B.A.,
Assistant to the Physiological Chemist, Animal Nutrition Section, Bangalore.
(Received for publication on 7th February 1935.)
The experiments to be described were carried out with the fodders reported
on in the first part of this series. The fodders were fed to mature bullocks and
the resulting urine collected quantitatively. The acid-base balance of the urine
was studied by the procedure given in detail in an earlier paper by Warth and
Krishna Ayyar [1930]. The main results obtained by the potentio-metric titra-
tion of urine are shown in Table I.
( 140 )
PROGRESSIVE RIPENING OF FODDERS ON MINERAL NUTRITION OF CATTLE. 141
TABLE I.
Total urinary excretion of acids and bases in c. c. N per 1,000 grams fodder.
Total fixed bases
.
.
.
.
.
Chlorides . . . . . .
Sulphates
.
.
.
.
.
.
Hippuric acid
.
.
.
.
.
Other organic acids
.
.
.
.
.
Total organic acids
.
.
.
.
.
Total acids
.
.
.
.
.
.
.
Excess of base
.
.
.
.
.
Carbon-di-oxide . . . . .
Ammonia
.
.
.
.
.
.
pH of urine . . . . .
pH of faeces . . . . .
Volume of urine in litres per day . .
Rhodes grass hay
(Bangalore).
1st Cut.
818.7
385.9
...
59.9
61.4
121.3
507.2
311.5
488.8
7.6
7.98
7.70
10.105
2nd Cut.
518.3
388.8
10.4
86.1
21.2
107.3
506.5
11.8
40.9
5.8
7.40
7.85
5.891
Aurangabad hay.
1st Cut.
264.5
76.6
2.1
99.1
71.3
170.4
249.1
15.4
36.3
6.7
6.62
7.42
3.074
2nd Cut.
202.1
60.3
1.5
102.5
25.7
128.2
190.0
12.1
13.5
3.4
6.25
7.40
1.912
3rd Cut.
138.5
38.9
1.2
85.5
32.4
117.9
158.0
—19.5
1.5
10.8
5.72
7.60
l.36l
Spear grass hay
(Bangalore).
1st Cut.
296.7
125.3
8.6
117.5
45.2
162.7
296.6
0.1
40.5
7.9
7.22
7.48
5.820
2nd Cut.
137.5
52.9
9.2
89.6
37.5
127.1
189.2
—51.7
1.8
63.7
5.88
7.30
2.074
Jouar hay (Sorghum).
1st Cut.
655.4
251.5
7.7
109.1
46.2
155.3
414.5
240.9
274.6
5.4
7.90
7.60
5.964
2nd Cut.
411.4
162.2
10.2
124.7
31.2
155.9
328.3
83.1
115.8
5.5
7.60
7.35
4.131
3rd Cut
330.1
136.7
12.0
119.8
21.5
141.3
290.0
40.1
41.9
3.3
7.40
7.25
3.543
142 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V, II
The results have to be examined from two points of view:—(a) The effect
of maturing of fodders on the acid-base balance of the resulting urine.
It has to be noted that with advancing maturity total fixed bases decrease,
chlorides decrease in all fodders except Rhodes grass hay, hippuric acid is irregular
but total organic acids decrease. pH of the urine tends to become lower because
of the decrease of bases and for the same reason the carbon-di-oxide content of the
urine diminishes. Further, it may be noted that the early cut fodders are marked
by the elimination of large volumes of urine. This diuresis is definitely attributable
to the large amount of alkalis in the food.
(b) Distinctive features of fodders.
1. Rhodes grass hay (Bangalore). High bases and chlorides; low hippuric
acid and low total organic acids.
2. Aurangabad hay. Bases low even in early cut and still lower when the grass
matures; acid-base balance of early cut, only a small excess of base; later cut
acidic.
3. Spear grass hay (Bangalore). Bases almost as low as Aurangabad hay;
chloride in early cut somewhat higher than Aurangabad hay, later falls rapidly.
Acid-base balance, even early cut does not yield excess of bases ; later cut shows
serious deficiency of bases. Later cut produces very definite nutritional acidosis,
marked by a large increase of urinary ammonia; the acidosis being due not to
increased acid product on but to deficiency of fixed bases.
4. Jouar hay. Bases and chlorides both moderately high. The amounts
decrease with advancing maturity, but even ripe Jouar yields more bases and
alkali than the first cut of either Aurangabad or Spear grass hay.
It is important to note that fodders 1 and 3 were grown on similar soil, yet
the one yields an highly alkaline urine and the other an acid urine. The species
of grass may, therefore, profoundly influence the mineral supply to and the acid-base
balance in the animal. It has already been observed that the stage of maturity
likewise exerts a profound influence in the same respects.
Excretion of acids. Both total organic and mineral acids decrease with
maturity ; but while total organic acids only fluctuate to a relatively small extent
and are of the same order of magnitude for all fodders, the mineral acids differ
widely in different species and generally fall very considerably with advancing
maturity. Rhodes grass hay is, however, an exception in this as in other respects.
Excretion of bases. Gravimetric determination of the bases was carried out
on an aliquot sample representing the urine of six consecutive days. The results
are set out in Table II. For comparison the value of total bases as
found by potentio-metric titration of urine on three consecutive days is also shown.
PROGRESSIVE RIPENING OF FODDERS ON MINERAL NUTRITION OF CATTLE.
143
TABLE II.
Urinary excretion of fixed bases in c. c. N per 1,000 grams of the fodder.
CaO
.
.
.
.
.
.
MgO.
.
.
.
.
.
.
Na 2 O.
.
.
.
.
.
.
K 2 O.
.
.
.
.
.
.
Total bases (Gravimetric) Average of six
days.
Total bases by Potentio-metric titration,
Average of three days.
Rhodes grass hay.
1st Cut.
0.92
24.38
288.20
545.10
858.60
818.70
2nd Cut.
24.20
30.98
191.10
293.50
539.78
518.30
Aurangabad hay.
1st Cut.
22.39
42.92
9.36
196.60
271.27
264.50
2nd Cut.
22.81
43.40
9.21
145.00
220.42
202.10
3rd Cut.
43.06
50.79
8.00
48.49
150.34
138.50
Spear grass hay.
1st Cut.
36.09
57.71
Nil
230.80
324.60
296.70
2nd Cut.
47.41
46.43
10.65
45.64
150.13
137.50
Jouar hay.
1st Cut.
10.63
35.37
Nil
633.90
679.90
655.40
2nd Cut.
19.34
30.67
Nil
375.60
425.61
411.40
3rd Cut.
24.92
41.29
Nil
290.80
357.01
330.10
144 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [ V. II
The figures by the two methods, as they do not cover the same period, are not
strictly comparable, but they should be much alike. It is remarkable, therefore,
that the potentiometric value is lower in every case. At present no explanation
is offered for this difference. It may be noted, however, that there is a very fair
parallelism between the two sets of data and hence the rapid and easy potentio-
metric method is justified for the purpose of comparing the acid-base balance
values of fodders.
The potash and soda ingested with the food are excreted mainly in the urine,
hence for the alkalis, the urinary excretion is an index of the intake. In every
fodder it will be noticed that the alkalis decrease with maturity. Rhodes grass
hay and Jouar hay are much richer in alkalis than the other two fodders. Rhodes
grass hay is unique in the amount of soda it provides. This is seen not only in
the fodder analysis table but in the present data on urinary excretion. It may be
noted in this connection that the pH of urine is most closely related to the out-put
of alkalis.
Excretion of lime and magnesia. The data regarding excretion of lime are of
special importance and are collected together in a separate table for emphasis.
TABLE III.
Intake and excretion of CaO and MgO in grams per day.
—
CaO intake .
CaO in urine .
MgO intake .
MgO in urine .
pH (Urine) .
Rhodes grass
hay.
1st cut.
28.12
0.12
14.52
2.24
7.98
2nd cut.
21.85
3.29
8.86
3.04
7.40
Aurangabad hay.
1st cut.
28.25
2.96
18.05
4.09
6.62
2nd cut.
24.57
2.94
14.24
4.03
6.25
3rd cut.
27.88
5.76
14.56
4.89
5.72
Spear grass
hay.
1st cut.
25.78
4.70
16.18
5.41
7.22
2nd cut.
26.99
6.21
13.14
4.38
5.85
Jouar hay.
1st cut.
18.61
1.01
20.78
3.39
7.90
2nd cut.
14.44
1.82
15.54
3.00
7.60
3rd cut.
10.82
2.47
14.69
3.96
7.40
It is evident from these figures that the excretion of lime is definitely not
proportional to the intake, but depends almost entirely upon the pH of the urine,
high pH leading to low lime excretion and low pH to increased lime excretion.
The increased deflection of lime and magnesia into the acid urine has already been
noted by the author in an earlier paper [1932]. It may be observed further that
this natural development of acidity (nutritional acidosis) has exactly the same
effect upon the deflection of calcium into the urine as may be produced experi-
mentally by the ingestion of hydrochloric acid [Givens & Mendel 1917] and of
ammonium chloride [Stewart & Haldane 1924]. The increase of lime in such
PROGRESSIVE RIPENING OF FODDERS ON MINERAL NUTRITION OF CATTLE. 145
urines suggests that the animal experiences difficulty in retaining minerals when
the urine becomes acid. The mineral balance data discussed below support this
view.
The excretion of magnesia in the urine is less regular but it tends to follow lime.
RELATION BETWEEN LIME AND PHOSPHORIC ACID IN URINE.
The amount of phosphoric acid in the urine of cattle is generally exceedingly
small. The figures in the accompanying table show, however, that there is some
relationship between lime and phosphoric acid, as the lime increases so the phos-
phoric acid decreases.
TABLE IV.
Relation between CaO and P 2 0 5 in urine.
—
Rhodes grass hay—
First cut
.
.
.
.
.
.
.
.
Second cut . . . . . . . .
Aurangabad hay —
First cut . . . . . . . .
Second cut
.
.
.
.
.
.
.
.
Third cut . . . . . . . .
Spear grass hay—
First cut . . . . . . . .
Second cut . . . . . . .
Jouar hay—
First cut . . . . . . . .
Second cut . . . . . . . .
Third cut . . . . . . . .
Grams per day.
CaO.
0.12
3.29
2.96
2.94
5.76
4.70
6.21
1.01
1.82
2.47
P 2 O 5 .
1.44
0.12
0.10
0.07
0.06
0.10
0.07
0.25
0.20
0.19
146 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V,
It would appear that fluctuations in the phosphoric acid content of cattle
urine (although the amounts are so small) are in some way significant of the urine
character and the balance of minerals.
ASSIMILATION OF CALCIUM IN RELATION TO URINE REACTION.
Balance experiments briefly summarised in the following table show that
calcium assimilation is closely related to the stage of maturity.
TABLE V.
Mineral balance.
—
Rhodes grass hay 1st cut. . .
„ 2nd cut. . .
Aurangabad hay 1st cut. . .
„
2nd cut. . .
„ 3rd cut. . .
Spear grass hay 1st cut. . .
„ 2nd cut. . .
Jouar hay
1st cut. . .
„ 2nd cut. . .
„ 3rd cut. . .
Grams per day P 2 O 5
Intake.
20.25
11.30
12.24
9.16
6.87
18.15
11.00
24.64
23.68
29.75
Out-put.
Faeces.
14.49
11.12
11.81
11.35
10.21
15.23
12.10
22.29
23.61
31.37
Urine.
1.44
1.12
0.10
0.07
0.06
0.10
0.07
0.25
0.20
0.19
Balance.
+4.32
+0.06
+0.38
—2.26
—3.40
+ 2.82
—1.17
+ 2.10
—0.13
—1.81
Grams per day CaO.
Intake.
28.12
21.85
28.25
24.57
27.88
25.78
26.99
18.61
14.44
10.82
Out-put.
Faeces.
18.70
18.11
24.04
21.90
22.48
19.07
18.21
14.92
13.81
10.26
Urine.
0.12
3.29
2.96
2.94
5.76
4.70
6.21
1.01
1.82
2.47
Balance.
+ 9.30
+ 0.45
+ 1.25
—0.27
—0.36
+ 2.01
+ 2.57
+ 2.68
—1.19
—1.91
It may be noticed that with the first cut fodders there is a positive balance
and with the second cut there is just a positive or slightly negative, while with the
third cut there is increased negative balance. This observation, however, does
not supply a chemical basis for distinction.
Having learnt now that urine reaction is definitely related to maturity, it
seems that calcium assimilation must be influenced by urine reaction, a conclusion
which is further supported by the fact (Table III) that urinary loss of calcium
is closely related to reaction of urine.
Admitting that vitamins play an essential part in the assimilation of calcium
and phosphorus, the data obtained in the present series of experiments indicate
that the urine reaction is another independent factor which exerts some influence
on assimilation.
SUMMARY.
1. Four typical fodders at different stages of maturity were fed to cattle and
the acid-base balance of the resulting urine studied
PROGRESSIVE RIPENING OF FODDERS ON MINERAL NUTRITION OF CATTLE. 147
2. It has been noted that the early cut fodders are marked by the elimination
of large volumes of urine, definitely attributable to the high amount of alkalis in
the food and that with advancing maturity the total fixed bases decrease and the
pH of the urine tends to become lower.
3. The bases in the urine of two fodders were very low even with the first cut.
Later cuts show serious deficiency of bases. One late cut fodder produced definite
nutritional acidosis marked by a large increase of urinary ammonia.
4. The species of grass and the stage of maturity both profoundly influence
the mineral supply to and the acid base balance in the animal.
5. Lime and magnesia show increased deflection into the acidic urine. The
excretion is not proportional to the intake but depends almost entirely on the
pH of the urine. This suggests that the animal experiences difficulty in retaining
minerals when the urine becomes acid. The mineral balance data discussed also
support this view.
6. It appears that there is an inverse relationship between urinary lime and
urinary phosphoric acid.
7. Urinary loss of calcium being closely related to the pH of the urine, it is
probable that calcium assimilation is influenced by urine reaction.
The author wishes to express his indebtedness to Dr. F. J. Warth, for his
interest and helpful advice in the preparation of this paper.
REFERENCES.
Givens, M. H., & Mendel L. B., (1917). J. Biol. Chem. 31, 421.
Krishna Ayyar, N, (1932). Ind. Jour. Vet. Sci. & Anim. Husb. 2, 300-305.
Stewart C., & Haldane J. B. S. (1924). Biochem. J. 18, 855.
Warth F. J., & Krishna Ayyar, N. (1930). Biochem. J. 24, No. 6, 1595.
THE INFLUENCE OF PROGRESSIVE RIPENING OF
FODDERS ON THE MINERAL NUTRITION OF CATTLE.
PART III. THE BLOOD CHARACTERISTICS AS INFLUENCED BY
PROGRESSIVE RIPENING OF FODDERS
BY
N. C. DAS GUPTA,
Assistant to the Physiological Chemist, Animal Nutrition Section, Bangalore.
(Received for publication on 7th February 1935).
The present paper deals with the blood characters obtained by feeding the
food-stuffs already described in the first paper. In order that the blood used for
analysis might be truly representative of the effect of the food-stuff, blood sam-
ples were not taken until the animals had been on the ration for at least twenty
days. Two animals were used and generally two blood samples were taken from
each animal during every experiment, at least a day's interval being allowed
between the two samples. The bleeding was always done before the animals
received their morning ration at 8 A.M., after they had fasted for about 15
hours. Mature bullocks were used to avoid the complications caused by growth,
lactation and other factors.
METHODS OF ANALYSIS.
In the earlier stages of this work determinations were made on the plasma,
but as plasma determinations required the collection and working up of two
separate blood samples for calcium and phosphorus respectively, the earlier pro-
cess was abandoned in favour of serum analysis in which a single blood sample
is used for the estimations of both calcium and phosphorus.
The blood was drawn from the jugular vein into a 15 c. c. centrifuge tube and
kept at room temperature (26° C.) for four hours before the serum was separated
by a centrifuge.
Many workers have estimated calcium in plasma and serum without removing
the proteins, but the author found difficulties in the estimation of calcium in
whole plasma. Some fibrous substance often separates when calcium oxalate is
precipitated from whole plasma and it is difficult to make this fibrous substance
adhere to the centrifuge tube. It is liable to be carried out and takes with it
some of the oxalate precipitate when the liquid is decanted for washing. The
fibrous organic precipitate in the tube is also undesirable because it consumes
some permanganate. Hence the author now carries out all blood calcium deter-
minations in the protein free filtrate of the serum.
( 148 )
PROGRESSIVE RIPENING OF FODDERS ON MINERAL NUTRITION OF CATTLE
149
The actual determination is made thus :—4 c.c. serum is made up to 40 c.c
with 7 per cent. trichloracetic acid, mixed thoroughly and filtered after half an
hour through an ashless filter paper (Whatman No. 40). The same filtrate is used
for both calcium and phosphorus estimations.
The method followed for the estimation of calcium is exactly that of Leoboff
[1929-30] as modified by Rymer and Lewis [1932], except that the trichloracetic
acid used for the separation of the proteins is different and the pH of the liquid
in which the calcium is precipitated is 5.0 instead of 6.2. Calcium is precipitated
in 7.5 c. c. filtrate in a 15 c. c. centrifuge tube with 0.5 c. c. saturated ammonium
oxalate at pH 5.0 (methyl red) and kept over night in the refrigerator. After 24
hours the tubes are centrifuged at 2400 R. P. M. for 30 minutes and the liquid
decanted off. The washings and titration are done as described by Rymer and
Lewis. The tests are always done in duplicate.
For the determinations of phosphorus the modification of Kuttner and Lich¬
tenstein [1932] has been adopted. One point has to be mentioned. Usually
inorganic phosphorus is estimated as soon as the protein free filtrate is available,
but when there is pressure of work it may be very inconvenient to do the
determination immediately. To find out whether a delay in determination is
permissible, blood filtrates were prepared and inorganic phosphorus determina-
tions made at regular intervals. The results are given in Table I.
TABLE I.
Effect of time on the inorganic phosphorus content of the trichloracetic acid filtrate
of serum.
Immediately . . . . . . .
After 48 hours
.
.
.
.
.
.
.
After 96 hours
.
.
.
.
.
.
.
Mgm. inorg. P per
100 c. c. serum.
Animal F.
7.81
7.94
7.81
Animal I.
6.62
6.76
6.58
The above figures show that even after 96 hours there is no increase in the
inorganic phosphorus content of the filtrate. This result differs from the obser-
vation of Sahyan [1933] who while working with whole blood filtrate of rabbits,
found an appreciable increase in the inorganic phosphorus content of blood on
allowing the trichloracetic acid filtrate to stand for 24 hours at room temperature.
150 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V, II
EXPERIMENTAL RESULTS.
1. Rate at which serum phosphorus attains constancy.
In certain cases Eckles, Gullickson and Pulmer [1932] found that after a
change of ration the plasma may take months to attain a constant again. It is
important to note that under the experimental conditions of the tests made at
Bangalore the blood attained a constant very much more rapidly.
TABLE II.
Rate of change of serum inorganic phosphorus with the change of phosphorus
content of ration.
Date.
3rd October 1934 . . .
2nd November 1934 . . .
7th November 1934 . . .
11th November 1934 . . .
14th and 15th November 1934. .
29th November and 1st December
1934.
18th December 1934 . . .
Daily P supplement.
{60 gms. Ca 3 (Po 4 ) 2
Begun
„
„
No supplement.
„
„
„
Serum inorganic P.
Animal B.
5.41
5.41
4.12
4.11
4.95
Animal I.
7.75
7.94
6.29
4.92
1.91
The above figures obtained by the author show that constancy was attained
here in less than three weeks.
This point is emphasised because our feeding tests generally could not be
continued for more than a month and the blood samples were taken during the
4th week of feeding. The figures in the table show that such samples were pro-
bably entirely representative of the ration fed.
2. Phosphorus content of the food in relation to the inorganic phosphorus of
blood serum.
The results in Table III show that a change in dietary phosphorus is always
reflected by a change of level of inorganic phosphorus in the blood serum, but large
changes in the intake produce only small changes in the serum. In these respects
the results agree with the findings of Palmer Cunningham and Eckles [1930].
Theiler, Green and du Toit [1927] and Malan, Green and du Toit [1923].