NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
52
STUDIES IN THE WOOL QUALITY OF PATTANWADI SHEEP [Vol. XXI, Part I,
TABLE VII
Analysis of variance of medullation percentages
Source
Age
Sex
A × S
Between animal within age, within sex
(Error 1)
Between animals
Region
R × A
R × S
R × S × A
Animal × Region within age, within sex
(Error 2)
TOTAL
D. F.
1
1
1
8
11
5
5
5
5
40
71
S. S.
1300
648
440
3562
5950
1431
149
118
109
1223
8980
M. S.
1300
648
440
445
..
286
30
24
22
31
R.
2.9
1.5
0.9
..
..
9.2**
..
Significant at 1 per cent level.
Mean values of medullation percentage for different regions.
Breech.
Neck
Shoulder
Side
Back
Withers
20.7
14.0
9.6
9.5
9.0
7.6
(4) Medullation. The medullation percentage varied from 0 per cent to 60
per cent. Generally the values of breech samples were highest followed by neck,
the rest being roughly of the same order as shown by the averages in Table III.
The range of variation in a fleece varied from 2 per cent to 46 per cent—Table III.
The analysis of variance Table VII shows the variation due to regions to be signi-
ficant at 1 per cent level. From the critical differences and the averages—Table III
it can be seen that breech differs significantly from each of the other regions at 1
per cent level. Withers, back, side and shoulder do not differ significantly from
March, 1951]
SUNANDA
NARAYAN
53
each other. Neck is significantly different from back at 5 per cent and from breech
and withers at 1 per cent levels. As such the regions can be conveniently grouped
as (1) breech (2) neck and (3) wither, shoulder side and back on the basis of medu-
llation percentage.
Sex and age
The averages of medullation percentages of mean values of wool samples of
sheep of different ages and sexes are given below.
Males
Females
Average
3¾ years
21.4
10.5
15.95
1½ years
8.0
6.9
7.45
Average
14.70
8.70
11.70
The average medullation percentage of samples of older sheep is higher than
that of younger sheep and of rams higher than that of ewes. However, the analysis
of variance shows these variations to be not significant. The regional groupings
as discussed above with reference to various characters may be as follows:
Length. (1) Neckand withers (2) shoulder (3) side, back and breech.
Diameter. (1) Neck and withers (2) shoulder, side and back (3) breech.
Medullation. (1) Neck (2) withers, shoulder, side and back (3) breech.
On the classing table if small differences in length are overlooked as can be
in carding wools and the fleece is divided out into different—qualities on the basis
of fineness and medullation, three divisions can be made as (1) neck and withers
—long and coarse wool—though withers is generally of lower medullation, it will
have to go with neck wool on account of its comparatively greater average diameter
(2) shoulder, side and back—finest and best part of the fleece and (3) breech-
short, coarse and highly medullated wool. As part of the neck is often coloured
in this type of sheep, the coloured part has also to be separately classified. These
principles were successfully employed by the large scale, shearing and grading opera-
tions undertaken by the Government in this area [Narayan 1946].
Proportion of different types of fibres
The proportion of hair, heterotypes and true wool fibres in wool samples of six
regions of 24 sheep three of each sex and of ages 1, 2, 3 and 5 years, were recorded.
The pure wool percentages varied from 100 per cent in younger ewes to 5 per cent in
5 years old rams. The heterotypes varied from 0 per cent to 86 per cent and hair
from 0 per cent to 50 per cent. Hair was completely absent in samples of all the
ewes except three—one 3 years old, and two 5 years old. Among rams, hair was
absent in all the one year old and in two years old sheep it was only up to 0.8 per
cent. Excepting one 5 years old owe, the hair percentage of rest of the animals was
below 19 per cent.
54
STUDIES IN THE WOOL QUALITY OF PATTANWADI SHEEP [Vol. XXI, Part I,
TABLE VIII
Average of wool hair and heterotype percentages of wool samples of 24 sheep for different
regions
Wool
Heterotype
Hair
Neck
64.2
34.0
1.8
Shoulder
76.0
23.2
0.8
Withers
68.3
30.5
1.2
Side
72.9
25.6
1.5
Back
71.5
27.0
1.5
Breech
55.5
40.8
3.7
The wool percentages of breech samples were generally lower and the hair and
heterotypes higher than those of the other regions, as can be seen by the averages
given in Table VIII. It has already been observed that the total medullation per-
centage is highest in breech regions which is partly dependent on the increased
number of hairy fibres found in this region as observed here.
TABLE IX
Analysis of variance of transformed figures of wool percentages
Source
Between Ages
„
Sexes
Age × sex
Between animals
Within age
}
Error
„ sex
Between animals
Between regions
Age × region
Sex × region
Age × sex and region
Animal × region
Within age
}Error
„
sex
TOTAL.
D.F.
3
1
3
16
23
5
15
5
15
80
143
S.S.
9187.67
7447.69
2683.97
12286.90
31606.23
3171.99
2082.77
1043.06
1469.91
10031.77
49405.73
M.S.
3062.56
7447.69
894.66
767.93
..
634.40
138.85
208.61
97.99
125.40
R
3.988*
9.698†
1.165
..
. .
5.059*
1.107
1.664
0.781
..
Note.—*Significant at 5 per cent level.
†Significant at one per cent level.
March, 1951]
SUNANDA
NARAYAN
55
The analysis of variance of wool percentages carried out after inverse sine tran-
formation—Table IX—shows that the variation due to regions is significant at
five per cent level.
TABLE IX A
Mean values of transformed values for different regions:
Breech
Neck
Withers
Back
Side
Shoulder
Critical difference for regions at:
5 per cent
1 per cent
48.4
55.6
56.6
59.8
60.9
62.8
6.23
8.26
According to the critical differences—Table IXA—whithers, back, side and
shoulder are not significantly different from each other. Breech differs significantly
from all the remaining regions and its differences from back, side and shoulder are
significant at 1 per cent level. Neck differs significantly from shoulder and breech at
five per cent level. The most convenient classification and regrouping of the
regions according to the above result will be (1) breech (2) neck and (3) shoulder,
side, back and withers. It may be recalled here that the same classification was
obtained on medullation percentage also which is influenced by the proportion of
medullated fibres.
TABLE X
Average values of hair, heterotypes and wool percentages of wool samples of groups of
three sheep of different ages and sexes
5 years
3 „
2 „
1 „
Rams
Ewes
Wool
51.5
63.6
76.2
82.2
58.1
77.9
Heterotypes
44.1
35.6
23.4
17.8
40.7
19.7
Hair
5.4
0.8
0.4
0.0
1.2
2.4
56
STUDIES ON THE WOOL QUALITY OF PATTANWADI SHEEP [Vol. XXI, Part I,
Age
From Table X it will be seen that the true wool percentages have decreased and
medulated fibres increased with age. The analysis of variance shows the variation
due to age to be significant at 5 per cent level.
TABLE XI
Ages
Means of transformed values
5 per cent critical difference for age
1 year
66.4
..
2 year
62.6
16.96
3 year
54.8
..
5 year
45.5
..
Critical difference for age shows that the differences beween 1 and 5 years and
2 and 5 years only are significant. Goot [1945] has established that in Romney
sheep hairiness is highest in the first year fleeces and lowest in the second year fleeces
increasing gradually thereafter to either the level of hairiness in the first year or a
lower level. According to the result obtained here, it is more likely that hairiness
leaches a peak at 4 or 5 years and has to be further investigated with fleeces of the
same sheep at different ages. It was observed that the heterotypes of older animals
were hairier and more easily distinguishable than the heterotypes of younger animals.
The medullation of only the heterotypes of animals of different ages was recorded
(Table XII).
The heterotypes of older sheep are more medullated than those of younger sheep
and with the higher proportion of heterotypes tend to increase the total medullation
percentage. The wool follicles seem to tend to grow hair rather than true wool fibres
as the sheep ages.
TABLE XII
Medullation percentages of heterotypes of wool samples from sheep of different ages
AGE.
1 Year
2 Years
3 Years
5 Years
Medullation
percentage
30.8 Per cent
37.5 Per cent
41.2 Per cent
48.8 Per cent
March, 1951]
SUNANDA
NARAYAN
57
Sex
The true wool percentages are higher and medullated fibres lower in wool samples
of ewes than of rams (Table X). This variation is seen to be highly significant
from the analysis of variance. Thus it can be observed that in general rams carry
hairier fleeces than the ewes.
The chief characteristic of carpet wools is the presence of hair and heterotypes
and higher variability in diameter of fibres. An ideal type of carpet wool according
to Von Burgen (Mathews Textile Fibres) should contain 35 per cent or more of
heterotypes and less than 4 per cent by weight of kemps. On this basis Pattanwadi
wool can be broadly classified into two grades, apparel wool usually cut from young
ewes and younger rams and superior carpet wool cut from older sheep.
Density of growth of fibres
The density of fibres recorded on six regions of 5 rams and 3 ewes varied from
500 to 2,500 fibres per sq.cm. The average for the different regions were:
TABLE XIII
Neck
1650
Shoulder
1409
Withers
1647
Side
1353
Back
1453
Breech
1584
Neck and withers show greater density of fibres than the other regions.
TABLE XIV
The density of fibres expressed as number of fibres per sq. cm. and as percentage of skin
area of 3 Pattanwadi rams and the average of South African plain bodied Merino
stud rams
Pattanwadi (1)
(2)
(3)
Average
Merino
Density
1796
1742
1358
1299
6544
Fibres
fineness
in microns
43.1
39.6
46.1
42.9
21.5
Percentage
skin
area
2.62
2.15
2.26
2.34
2.38
Note.—The values for Merino have been taken from Bosman [1941].
Compared to the density of fibres in Merino of 6544 sq.cm. the average of 1299
in Pattanwadi is very low (Table XIV). But the percentage skin area occupied by
58
STUDIES IN THE WOOL QUALITY OF PATTANWADI SHEEP [Vol. XXI, Part I,
wool is of the same order, the difference in number of fibres being made up by higher
average diameter of the fibres.
TABLE XV
The average density of fibres of different animals and their respective yields
Rams
1
2
3
4
5
Average
Ewe
1
2
3
Average
Density
1871
1796
1742
1692
1358
1692
1575
1062
1033
1223
Wool yield in
ounces.
29.5
20.0
21.5
21.1
17.0
21.8
22.5
15.5
16.0
18.0
The wool yield follows, density of fibres being greater with greater density
fibres of—Table XV.
Hence density of fibres is an important factor influencing yield. Also density
of fibres in rams is generally greater than in ewes and to a certain extent is respon-
sible for the higher yields of rams apart from the variation in size and skin area.
Variation of different characters of wool with season
Samples were taken from six different regions of three rams, both in autumn and
in spring, just before shearing, the period of growth in each case being six months.
The average length diameter and crimp of these samples were recorded. Length
of fibres was generally greater in autumn samples than that of the corresponding
spring sample, the difference ranging from 0.8 to 3.8 in., the average of differences
being 0.42in.±0.192 in. significant at 5 per cent level. The number of crimps per
inch of spring samples were more than the values for the corresponding samples
in autumn, the differences ranging from 0 to 3.1, the average of differences being
1.37 ± 0.241 significant at 1 per cent level. The average diameter of autumn
samples were generally greater than the values for the corresponding spring samples,
the differences ranging from —5.3 to 16.2 microns. The average of differences
4.69 ± 0.144 microns was found to be significant at 1 per cent level. Thus the spring
clip was found to be finer, shorter and crimpier than the autumn clip of the same
animal.
March, 1951]
SUNANDA
NARAYAN 59
FIG. 1. Growth of wool on the shoulder regions of two sheep.
60
STUDIES IN THE WOOL QUALITY OF PATTANWADI SHEEP [Vol. XXI, Part I,
Comparing the autumn and spring wool yield of 48 ewes, the autumn yields
were found to be generally higher than the spring yields, the differences ranging
from—4.6 to 5.0 ounces, the average of differences, 1.16 ± 0.394 ounces being signi-
ficant at 1 per cent level. This result is in agreement with the above observations
that spring clip is finer and shorter, variations in both these characters tending
to decrease the yield. Bosman [1937] has shown that in Merino sheep of South
Africa, usual climatic changes have no influence on wool quality provided the sheep
are kept on the same diet throughout. Also very recently it has been announced
that a rise in temperature has increased the growth rate of wool in Merino and Corrie-
dales in Australia [Wool Record, 1949]. Apart from the influence of climatic changes
in different seasons, the differences in quality and quantity of wool clipped in autumn
and spring noted here, have to be largely attributed to the changes in conditions of
pasture as the monsoon falls in the period of growth of the former.
Shearing once a year or twice a year
The prevailing custom in North Gujrat is to shear sheep twice a year—once in
March, April and again in September, October. Against this, shearing once a year
could be observed either in spring or in autumn. The growth of wool in each case
was studied by recording lengths of samples taken every month from the second
month of shearing, from six regions of each six ewes, three of which were shorn in
spring, and the other three in autumn. The averages of mean lengths of the samples
of the two groups are given in Table XVI and the growth of wool in one ewe of each
group in Fig. 1.
TABLE XVI
Average lengths of samples from ewes left without shearing from September to September
and from April to April of subsequent year in inches
September to Sep-
tember.
April to April .
2
1.20
0.99
3
2.12
1.19
4
2.31
1.69
5
2.52
2.04
6
3.06
2.55
7
3.37
3.11
8
3.62
3.52
9
3.31
3.88
10
3.19
4.31
11
2.84
4.82
12
03.1*
4.20
* Note.—1.—10th.—average of only 2 ewes
2.—11th.—average of only one ewes
The mean length of fibres of the ewes of the autumn group, increased upto the
seventh month only and decreased after that. One ewe died in the tenth and
another in the eleventh month owing to other causes. In the third ewe, the average
length of fibres at the end of the year was less than that at 6 months. Hence shearing
once a year in spring was observed to be not feasible.
The average length of wool samples of ewes shorn in the spring group of ewes
increased upto the eleventh month and slightly decreased in the twelfth month in
2 ewes and increased in the other ewe. There were signs of breaking of wool in a
few of the other sheep also which had already been shorn in autumn, and was
probably due to the late shearing carried out in the third week of April. By suitably
shifting back the shearing date, shearing once a year could be done in spring.
March, 1951]
SUNANDA
NARAYAN
61
TABLE XVII
The wool length and yield records of sheep selected for determining the effects of shearing once a year or twice a year
Serial
number
1
2
3
4
5
6
7
8
9
10
11
12
Tag number
F. 70
F. 67
F. 185
F. 34
203
211
P. 58
167
F. 23
136
208
F. 74
Mean
Length in
autumn
(inches)
1.9
2.0
2.1
2.5
2.7
2.7
2.8
2.8
2.8
3.2
3.3
3.5
2.72
Yield in
autumn
(ozs.)
13.0
12.0
19.2
16.0
21.0
21.0
16.5
11.0
18.5
19.0
17.8
130
16.50
Length in
spring
(inches)
3.2
3.1
2.5
2.9
2.7
2.7
2.7
2.7
2.8
2.8
2.9
3.0
2.83
Yield in
spring
15.2
16.5
16.0
15.5
15.5
19.2
13.0
21.0
14.2
16.8
14.0
13.5
15.87
Sum of
lengths
(inches)
5.1
5.1
4.9
5.4
5.4
5.4
5.5
5.5
5.6
6.0
6.2
6.5
5.55
Total
yield
(oz.)
28.2
28.5
35.2
31.5
36.5
40.2
29.5
32.0
32.7
35.8
31.8
26.5
32.37
Tag number
F. 75
F. 79
F. 78
138
192
172
142
189
F. 76
149
187
127
..
Length
in
in autumn
(inches)
1.9
1.9
2.4
2.5
2.8
2.8
2.8
2.9
2.9
3.2
3.3
3.4
2.73
Length
in spring
(one year)
(inches)
5.3
3.5
5.2
4.4
4.4
5.0
4.5
5.3
5.9
4.8
5.8
6.8
5.08
Length
in spring
(one year).
22.2
23.5
20.8
29.5
34.5
30.0
32.5
30.8
31.5
34.5
26.0
33.5
29.11
Total
yield in
previous
year
(oz.)
..
..
..
..
33.7
..
..
..
..
37.8
31.6
..
..
March, 1951]
SUNANDA
NARAYAN
63
be carried out in this breed also to find out the relation between quantity and quality
of milk and wool production and help the breeders to get the best out of their sheep.
It has been shown that the different characters of wool vary in different parts of
the fleece. To make up uniform lots for marketing of wool, it is necessary to examine
the entire fleece and divide it into different parts and grade them separately as
required.
When comparing the quality of samples of wool from two sheep the influence
of age, sex and season on different characters of wool should be taken into consi-
deration. It has been observed that generally ewes carry finer and less medullated
wool than the rams. By choosing a ram of the same wool quality as the ewe with
reference to these two characters, female progenies of finer wool than the mothers
may be expected. The studies recorded here on the relation between age, sex, and
wool quality, have to be considered as preliminary investigations which have shown
that more detailed observation on these problems are likely to be fruitful.
Contrary to the general impression that shearing Indian sheep once a year is
not feasible, shearing once a year in spring could be successfully adopted in these
areas, which would lead to improvement in staple length and reduction in cost of
shearing.
ACKNOWLEDGMENTS
I am indebted to Mr. N. L. Narayan for much of the information on the Pattan-
wadi breed and to Dr. B. K. Vaidya for general guidance.
REFERENCES
Albibon et al (1948). Lacaune Ewes—correlation between the production of wool and milk.
Abstr. J. Text. Inst. 2,40
Bosman, V. (1937). Biological studies on South African merino wool production. J. Text.
Inst. 28 8, Wool Record, (1949), 76 No. 2105.
Bosman, V. (1941). Studies on Merino Wool production plain-bodied and Developed Merino
sheep. II—Onderstepoort, J. vet. sci. Anim. Indust. 17 No. 1 and 2.
Goot, H. (1945). Hairiness in Wool, New Zealand. J. Tech. 27, Sec. A. No. 2.
Jones, J. M. (1928). Variations in yield and number of shearings per year—Wool quality—
S. G. Barken, 27.
Mathews. Textile Fibres, 5th Ed., (495).
Narayan, N. L. (1946). Definition of Baroda Wool Grades. Indian J., vet. Sci. XVI (III).
Vaidya, B. K. and Batt, P. N. (1947). Indian Wool, Curr. Sci. July 1947.
ABSTRACTS
The Accuracy of Diagnostic Methods used in the Detection of the Tuberclosis
Cattle. GREGORY, T. S. (1949). Aust. vet. J. 25, (7)
T HIS paper considers the usefulness of diagnostic methods suitable for appli-
cation in Australia. Consideration of clinical examination has been omitted.
It has been mentioned that the old subcutaneous method of testing appeared to be
accurate from the results obtained after slaughter. The accuracy was found to
be between 80 per cent to 90 per cent. One of the reasons ascribed to the high
degree of accuracy was the relative low potency of the old tuberculin used. Later
when synthetic medium tuberculin was used by the intradermal method, it was
mentioned that the number of non-reacting affected ones decreased and N.V.L
reactors increased as a result of the diagnostic product being more potent. The
author mentions that the second simultaneous injection into the vulvar lip recom-
mended by American workers was not followed in Australia.
While listing some factors influencing the accuracy of tuberculin test it has been
pointed out that potency is one of the chief factors. Low potency tuberculin ensures
high proportion of tuberculous cattle amongst the reactors and tends to leave many
affected animals undetected, while the stronger product reduces affected non-
reactors and increases N.V.L. reactors. It has also been pointed out that it is neces-
sary to adjust the potency so as to overcome the influence of environmental
conditions like non specific sensitising agents. The method of testing has also
been shown to be one of the factors influencing the accuracy in diagnosis. The
intradermal method has universally proved to be the most suitable. The additional
accuracy vouchsafed by simultaneous caudal and vulvar injections has not been
found to be so in the author's country. A single reading after 72 hours was found
to be in no way inferior to the 96 hours method. Personal observations on animals
tested at the laboratory indicate that the cervical site and skinfold measurements
were more accurate than caudal fold site. The third factor mentioned was infection
with other organisms resulting in non specific sensitisation. Although there is little
doubt that infection of cattle with avian type tubercle bacillus must be an important
factor in tuberculin testing, it appears its importance might have been over estimated.
It is essential to use a comparative test to eliminate this factor on the basis of the
American opinion tending to show increased N.V.L. reactors on farms with tuber-
culons poultry. By using a comparative test with avian and mammalian tuberculin
cross reaction to Johne's disease could be discerned, as in that case, the avian tuber-
culin will give more pronounced reaction than mammalian tuberculin.
The so-called 'skin tuberclosis' may sensitise animals to mammalian and
avian tuberculin. Close contact with human consumptives may also lead to tem-
porary sensitisation so long as the supply of infectious material is present. Non
specific sensitisation may also result from presence of non acid-fast-bacilli as in
Traumatic paricarditis and lung abscesses with Corynebacterium pyogenes. Recent
65