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VETERINARY STUDIES



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THE MACMILLAN COMPANY

NEW YORK • BOSTON • CHICAGO • DALLAS
ATLANTA ■ SAN FRANCISCO

MACMILLAN & CO., Limited

LONDON • BOMBAY ■ CALCUTTA
MELBOURNE

THE MACMILLAN CO. OF CANADA, Ltd.

TORONTO



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VETERINARY STUDIES



FOR



AGRICULTURAL STUDENTS



BY

M. H. REYNOLDS, B.S., D.Y.M, M.D.

PROFESSOR OP VETERINARY MEDICINE, UNIVERSITY OF MINNE-
SOTA; MEMBER INTERNATIONAL COMMISSION ON CONTROL
OF BOVINE TUBERCULOSIS; MEMBER AMERICAN
VETERINARY MEDICAL ASSOCIATION



EIGHTH EDITION



THE MACMILLAN COMPANY
1922

All Rights Reserved






%', ; Jr' ; ^^'f 'r,.' '* I ^/'^ /'paiNTJSD IN THE UNITED STATES OF AMERICA



G



Copyright, 1910, and 1922,
By the MACMILLAN COMPANY,



Set up and electrotyped. Published December, 1910. Reprinted August, 1911.
Eighth edition. — Set up and electrotyped. Published November, 1922.

kviAlM LIBRAKY. AGRICULTURE DEKV



PREFACE TO EIGHTH EDITION

I WISH to thank my many fellow teachers who have shown
appreciation by continuing to use this textbook in spite of inac-
curacies and evident need of revision. I wish to emphasize again
the fact that Veterinary Studies is intended to some extent as a
teacher's outline. Each teacher must add material as he may
think wise, or leave out entire subjects according- to local needs.
I find that very many pupils taking veterinary class work in ag-
ricultural schools need review work on physiology. The necessity
for a practical working knowledge of physiology is evident.
Some knowledge of anatomy is plainly necessary in order that
disease processes may be located, and that students may under-
stand animal conformation. Some elementary pathology is
absolutely necessary in order that pupils may have some under-
standing of what disease processes really are.

Causes and prevention of diseases should be considered as of
paramount importance, and only carefully selected diseases
should be presented. These should be diseases which are uniform
in symptoms and history and therefore easily recognized, and of
such diseases, those that are rather easily and simply treated or
are preventable.

There may be perhaps exception to this, in case of stock
owners who do not have access to trained veterinarians. In
such case it is a matter of plain common sense that they must
do the best they can for themselves.

However, we veterinary teachers of agi-icultural students
should have constantly in mind the fact that we are educating
expert stockmen — not poorly trained quack veterinarians. The
student who has had a proper course should better appreciate
the competent veterinarian and call him more promptly and
intelligently.

Appreciation is due JP. f^ A 1Iewitt,"Tr£ the College of Agri-
culture, University of ATiiiuoula, for' >e^ wing and criticizing
the lectures on anatomy and phvsiologv.

4083S2

^^ *^ M. II. REYNOLDS.

University of Minnesota,
September, 1922.



PKEFACE TO FIRST EDITION

During ten years' experience in teaching veterinary subjects
to agricultural students, certain difficulties have l)cen constantly
encountered. Others doing this work have probably had similar
experience. There has been the difficulty of imperfect training,
or entire lack of previous training, in physiology and other sub-
jects which medical men recognize as fundamental. There is
always present the difficulty of presenting a technical subject
in untechnical language ; difficulty in securing satisfactory illus-
trations; and difficulty in giving the kind and character of
veterinary work which is generally demanded and conceded as
necessary, without giving our students a sort of training which
will turn some of them into unqualified practitioners. There
has been serious difficulty in covering, without a textbook, a sat-
isfactory amount of ground. Many students do not take notes
well.

During this time I have been more and more impi-essed with
the belief that a textbook, wisely illustrated and carefully edited
for its legitimate use, would enable me to cover very much more
ground within the available time.

The style of editing that has been adopted was selected with
a view to presenting the subject matter to students in a con-
spicuous and easily grasped way. This must be our excuse and
answer to criticism which the expert printer may legitimately
make.

This work has been written more particularly as a text for
veterinary classes in agricultural schools and colleges; but it is
hoped that it may prove helpful also to stockmen who are not
able to attend our agricultural colleges, but who care to know
more of the animal machines with which they are working. I
take this occasion to deprecate the blind dosing of stock to which
farmers and stockmen are very much inclined. The student
should realize the impossibility of writing a prcscrii)tion that will

vii



viii PREFACE TO FIRST EDITION

fit all cases of a certain disease, and he will hesitate to risk the
use of medicines of which he knows very little in diseases of
which he knows less.

Lecture notes which have been collected during a period of ten
years have formed the basis for this w^ork, and I am now unable,
in many cases, to give credit to authorities that have been con-
sulted, where credit is fairly due.

Illustrations have not been used in any case merely as pic-
tures. Every one is intended to illustrate something and make
that illustration as impressive as possible.

Suggestions to the teacher. It is not intended that this text-
book should entirely supplant lecture work. On the contrary,
nearly every lesson may be supplemented to advantage and so
give opportunity for originality and the greatest effectiveness.
It will be readily understood that certain subjects are of great
importance in some states, and unimportant in others. Each
teacher should add what he thinks best for his grade of pupils
and his local needs.

"When time permits much time can be profitably spent on
more extended anatomy work, especially for students who wish
advanced live stock work. It can be readily illustrated and
easily impressed : for instance, that smooth or rough hips de-
pend upon a fraction of an inch, more or less, on the external
angle of the ilium ; and that high or low" withers, in the main,
depend upon variations in the length of the superior spinous
processes of the dorsal vertebrae ; and that conformation depends
upon the bony skeleton and muscular developments.

IVIuch time with considerable actual practice should be given
to the study of unsoundness ; to common forms of lameness, and
the types of conformation which tend toward these unfortunate
conditions. Common irregularities of the teeth are easily illus-
trated in classroom. These are given as suggestions and to im-
press the fact that this text is not expected to cover the entire
field of veterinary teaching for all agricultural colleges.

I respectfully suggest that teachers should insist upon study
of illustrations. In my own class work I find the constant diffi-
culty that students glance at the illustrations carelessly and
hurriedly, and thus fail to get the benefit which they might
easily have. Students may be selected at random and asked to



PREFACE TO FIRST EDITION ix

draw upon the board, from memory, illustrations from the les-
son for that day. After a few practice lessons of this kind,
students easily learn how to study textbook illustrations.

M. H. REYNOLDS.
University of Minnesota,
October, 1903.



CONTENTS



ANATOMY

LECTURE PAGE

I. ANATOMY

Bones. — Kinds, peculiarities, development, structure and
composition.

Head. — Face, cranial, and hyoid bones; dentition of
horses, table; dentition of cattle, table; estimating
age by teeth; original application, common disorders 1

II. OSTEOLOGY

Spinal column. — General characteristics of vertebrae.
Cervical, dorsal, lumbar, sacral, and coccygeal ver-
tebrae.

Sternum. Eibs. Practical application, common dis-
orders 7

III. FRONT LIMB

Shoulder, arm, forearm, and foot — bones of, common
disorders 10

IV. POSTERIOR LIMB

Pelvis, thigh, leg, and foot — bones of, practical applica-
tion, disorders 14

V. FOOT

Bones, horny hoof, matrix, plantar cushion, back ten-
dons, good foot described, practical application, dis-
orders of the foot 19

VI. ARTICULATIONS (JOINTS)

General groups, examples; varieties of freely movable,

immovable, slightly movable.
Structures at joints; articulations described, practical

application, disorders 24

VII. MUSCULAR SYSTEM

Peculiar property of muscle, kinds, classification, parts,
microscopic structure, source of heat and power,
practical application, disorders 29



^ii CONTENTS



LECTURE



PAGE



VIII. NERVOUS SYSTEM

General function, nerve centers.

Cerebrospinal system. — Brain, cranial nerves, spinal

cord, spinal nerves.
Sympathetic system. — Composition, ganglia, sympathetic

nerves, practical application.
Disorders ^^

IX. CIRCULATION

Blood. — Circulatory apparatus, course of the blood,
blood supply of the body, principal arteries and veins.
Lymphatic system. — Parts, function.
Practical application, disorders 42

X. RESPIRATION

Definition, stages, parts, purpose, respiratory apparatus,
practical application, disorders 51

XL DIGESTIVE APPARATUS

Definition, organs of digestion, anatomy of each, prac-
tical application 57

XII. PHYSIOLOGY OF DIGESTION

Definition of digestion, food groups, course and history

of each group, practical application and suggestions 64

XIII. URINARY ORGANS

Structure, function, and physiological operation of each,
practical application, disorders 68

XIV. MAMMARY GLANDS

Anatomy, function, products, blood supply, nerve supply,
and nerve control, practical application, disorders . 72

PATHOLOGY
XV. PATHOLOGY

Hyperaemia (congestion), inflammation, fever, heat pro-
duction and expenditure, symptoms of fever, results
of fever, practical application 77

XVI. PATHOLOGY {Continued)

Hemorrhage, dropsy, hypertrophy, atrophy, degenera-
tions and infiltrations, collapse, syncope, death, ne-
crosis, practical application '• 83



CONTENTS



Xlll



LECTURE

XVII.



XVIII.



PAGE



WOUNDS



Healing, and development of new blood vessels.
Healing of osseous, cartilage, and nerve tissues. New
tissue, how skin recovers a surface 88

WOUNDS (Continued)



Bad treatment, bleeding, sewing, bandaging, washing,
dry treatment, maggots, practical suggestions



91



CAUSE AND PREVENTION
XIX. CONTAGIUM

The individual bacterium, plagues in history, dissem-
ination, development of outbreaks, body entrance,
method of injury, resistance, how destroyed in nature,
classification, practical suggestions 96

XX. DISINFECTION

Purpose, sources of infection, thoroughness, attendants,
how to burn a carcass, common disinfectants,
methods of disinfection 102

XXI. HEREDITY— AIR

Theory of heredity in relation to disease, in-and-in breed-
ing.

Air impurities, relations to disease, standards of purity,
ventilation, practical application 106

XXII. VENTILATION

Stable air, necessity, unventilated air, natural forces,
air currents, outlets 109

XXIII. VENTILATION {Continued)

Stable construction. — Space, location, stable construc-
tion for ventilation, ventilation, amount of air needed 114

XXIV FOOD AND WATER

Food. — Excess, deficiency, bulk, quality, balance, inter-
vals, poisonous foods.
Water. — Excess, deficiency, parasites, sewage, intervals.
Practical application 119



xiv CONTENTS



PARASITIC DISEASES

LKCTURE PAGl

XXV. PAKASITISM

Parasitism. — Sources, how nourished, effect on host,
general prevention, general treatment, practical ap-
plication.

External Parasites. — Lice, flies, ringworm, sheep ticks,
ticks, treatment and suggestions for each .... 124

XXVI. SHEEP SCAB

Body scab, foot scab, head scab, general prevention,
general symptoms, treatment, dips, dipping, disin-
fection 130

XXVII. MANGE

Horse mange and cattle mange, cause, symptoms, treat-
ment of each 137

XXVIII. INTERNAL PARASITES

Bets, roundworms, tapeworms, treatment ...... 141

XXIX. NODULE DISEASE OP SHEEP

General history, cause, injury, diagnosis, treatment,
prevention 145

XXX. STOMACH WORM (SHEEP)

Parasite, life history, symptoms, treatment, drenching
sheep, management of infected flock, prevention . 149

XXXI. VERMINOUS BRONCHITIS, NASAL
GRUB, AND CATARRH

Verminous bronchitis. — Cause, life history of parasites,

symptoms, treatment, prevention.
Nasal grub. — Cause, life history, symptoms, treatment.
Catarrh. — Simple catarrh defined, causes, prevention,

treatment 153

INFECTIOUS DISEASES
XXXII. ACTINOMYCOSIS (LUMPY JAW)

Description, relation to public health, parts involved,
treatment 158



CONTENTS XV

LECTURB ""AGE

XXXIII. ANTHRAX

History, distribution, susceptible animals, cause, trans-
mission, introduction and spread, incubation, symp-
toms, post mortem, diagnosis, vaccination .... 163

XXXIV. SYMPTOMATIC ANTHRAX

Cause, symptoms, post mortem, prevention, vaccination 167

XXXV. BACILLUS NECROPHORUS INFECTIONS

Explanation, cause, infection, foot rot, lip-and-leg ul-
ceration, canker sore mouth, necrotic stomatitis, symp-
toms, treatment, management, etc., for each . . . 170

XXXVI. FOOT-AND-MOUTH DISEASE

Definition, symptoms, similar diseases, dissemination,
prevention, treatment 177

XXXVII. HEMORRHAGIC SEPTICEMIA

Etiology, history and development, symptoms, post mor-
tem, summary, differential diagnosis 180

XXXVIII. TEXAS OR TICK FEVER

Economic importance, causes, trananission, suscepti-
bility, incubation, symptoms, post mortem, prognosis,
treatment, prevention, tick extermination, vaccination 185

XXXIX. TUBERCULOSIS

Prevalence, cause, modes of infection, structures af-
fected, spiiptoms, diagnosis, treatment, prevention,
summary, disposition of tuberculous cattle, accredited
herd plan 192

XL. TUBERCULIN TEST FOR TUBERCULOSIS

Tuberculin effect on health, accuracy, thermal, intra-
dermal, and ophthalmic tests, importance to breeders 198

XLI. GLANDERS

Susceptible animals, causes, incubation, symptoms, acute
eases, chronic eases, farcy, diagnosis, mallein tests,
prevention, suggestions 203



xvi CONTENTS

LECTURE PAGE

XLII. HOG CHOLERA

Definition, symptoms, autopsy, cause, how scattered,
vaccination, common mistakes, suggestions . . . 208

XLIII. COMMON MINOR DISEASES OF SWINE

Posterior paralysis, congestion of the lungs, constipa-
tion, cause, symptoms, treatment of each, drenching
swine, suggestions 215

DIETETIC DISEASES
XLIV. AZOTURIA

Prevalence, history, parts affected, duration, causes,
symptoms, prevention, treatment, prognosis . . . 218

XLV. LYMPHANGITIS (ELEPHANT LEG)

Cause, symptoms, prevention, treatment, prognosis . . 222

XLVI. LAMINITIS (FOUNDER)

Definition, symptoms, cause, pathology, termination,
prevention, treatment 224

XLVII. HEAVES

Definition, cause, symptoms, prevention, post mortem,
treatment 227

XLVIIL HOVEN, OR BLOAT (ACUTE

TYMPANITES)
Definition, causes, symptoms, treatment, prevention . 230

XLIX. PARTURIENT PARALYSIS (MILK

FEVER)

Causes, symptoms, prevention, treatment, prognosis . 233

L. CHOKE

Explanation, symptoms, prevention, treatment, general
suggestions 238

MISCELLANEOUS DISEASES
LL UNSOUNDNESS

Unsoundness, normal condition, ringbone, sidebone,
spavin, splints, curb, bog spavin, open joint, hygromas,
miscellaneous unsoundness 241



CONTENTS



xvii



LECTURE

LII.



PAGE



UNSOUNDNESS {Continued)

Examination at rest, in motion, examination in detail.
Lameness. — Locating lameness, tests 249



OBSTETRICS

LIII. OBSTETRICS

Organs described, normal periods of gestation.
Accidents of pregnancy. — Sporadic abortions, infectious
abortions, symptoms, results 254

LIV. OBSTETRICS (Continued)

Infectious abortion. — Causes, virus, dissemination, in-
fection, results, importance, various classes of stock,
diagnosis, prevention, management of aborting herd,
disinfection, medical treatment, vaccines, calves . . 259

LV. OBSTETRICS {Concluded)

Accidents of pregnancy. — Eetention of fetus, volvulus,
or twist.

Accidents of parturition. — Infection, inflammation of
the uterus, inversion of the uterus, retention of the
afterbirth, hemorrhage 264

LVI. DISORDERS OF THE UDDER

Garget. — Definition, causes, symptoms, results, preven-
tion, treatment.

Udder diseases and accidents. — Injuries, obstruction,
warts, eowpox, etc 269

LVII. DIFFICULT PARTURITION

Difficult parturition. — Nature's plan, normal presenta-
tions, causes of difficulty, common faulty presenta-
tions, aid, suggestions, operations 274



MEDICINES
LVIII. COMMON MEDICINES

Common measurements and weights, giving medicines,
various common medicines as to physiological effects,
doses and uses 280



sviii CONTEXTS



LEC



PAGE



LIX. COMMOX MEDICIXES (Continued)

Various common medicines, as to physiological effects.
doses and uses - ^

LX. COMMOX MEDICIXES ^Concluded)

Various common medicines, physiological effects, doses
and uses 287

MINOR SURGICAL OPERATIONS
LXI. MIXOR SUEGICAL OPERATIOXS

Castration, various kinds of stock- Dehorning, by caus-
tic, shears, saw. Docking. Draining abscess. Semoc-
ing varts. lapping for hloot 291



ILLUSTRATIONS



PAGE

T Skeleton. B.A.I ^«^'"^ ^

o

2. Horse Skull. Chcuieau

3. Teeth of Horse 6 Years Old (Lower Jaw) ^

4. Teeth of Horse 8 Years Old (Upper Jaw). Oarke .... 4

5. Teeth of Horse 20 Years Old (Lower Jaw). Clarke .... 5

6. Grinding Surface of Molars. Euidekoper ^

7. Typical Cervical Vertebra. Chauveau '

8. Typical Dorsal Vertebra (Front View). Chauveau .... 8

9. Typical Lumbar Vertebra (Front View). Cliauveau .... 8

10. Lateral View of the Sacrum. Chauveau ^

11. Anterior Limb of the Horse. Chauveau H

12. Posterior Limb of the Horse. Chauveau 1-^

13. Bones of the Horse 's Foot. Chauveau 19

14. The Hoof. Chauveau

15. The Hoof Matrix. Chauveau -^

16. Voluntary Muscle. BeynoJds ^^

17. Muscle Fibers. Hewes ^^

18. The Cerebrospinal Nervous System. Magnin 33

19. Neuron ^^

20. Medullated Nerve Fibers ^^

21. Spinal Cord and Brain in Diagram. Beynolds 36

22. Relation of the Sympathetic and Cerebrospinal Systems, Partly

Diagrammatic. Chauveau 38

23. Circulation, General View. Magnin 43

24. Circulation, Diagrammatic. No. 1, BeynoJds; No. 2, after Overton 44

25. CapiUary Circulation. Eddy •*5

26. The Lymphatic System (Human). Eddy 48

27. A Lymph Node. Eddy ^^

28. Respiration in Diagram. Eeynolds 52

29. Stomach of the Horse (External and Internal Views). Chauveau 58

30. Stomach of the Cow. After Chauveau 59

31. Section of Horse Kidney. Chauveau 68

32. Urinary Apparatus in Diagram. Eeynolds 69

33. One Quarter and Teat of the Cow 's Udder. Tlianhoffer ... 72

xix



XX ILLUSTRATIONS

FIO. PAGE

34. Milk Vesicles and Outlet Ducts. Chauvecm 73

35. Badly Treated Wire Wound. Reynolds 91

36. General Groups of Bacteria. Reynolds 99

37. Ventilation. Paige 109

38. Ventilation. Paige 112

39. Ventilation. Paige 115

40. Cupola A^entilation. Paige 116

41. Ventilation. Paige 116

42. Cattle Louse (Female). Neuman . 126

43. Sheep Tick and Enlarged Proboscis. Neuman 128

44. Plain Case of Sheep Scab 131

45. Sheep Scab Mites. Curtice, Lugger, Pettit 132

46. Mange Mite. Neuman 137

47. Horse Botfly and Larva. Neuman 141

48. Horse Bots and Botfly. B. A. I 142

49. Common Tapeworm of Sheep. Curtice 144

50. Nodule Disease. Reynolds 146

51. Stomach Worm on Tip of Grass Blade. Ransom 149

52. Sheep Gadfly. Brauer 155

53. Actinomycosis (Lumpy Jaw). Reynolds 159

54. Actinomycosis. Reynolds 160

55. Actinomycosis. Reynolds 160

56. Bacterium Anthracis. Reynolds 163

57. Bacillus Necrophorus. B. A. I .... 170

58. Foot Eot (Sheep). Williams 171

59. Lip and Leg Ulceration. B. A. 1 175

60. Hemorrhagic Septicaemia. Reynolds 181

61. Hemorrhagic Septicaemia. Reynolds 182

62. Hemorrhagic Septicaemia. Reynolds 183

63. Hemorrhagic Septicaemia. Reynolds 184

64. Texas Fever Tick. Pettit 185

65. Bovine Tuberculosis. Reynolds 192

66. Bovine Tuberculosis. Reynolds 193

67. Bovine Tuberculosis. Reynolds 194

68. Bovine Tuberculosis. Reynolds 195

69. Glanders (Farcy). Reynolds 204

70. Glanders (Farcy). Reynolds 205

71. Glanders (Farcy). Reynolds . 206

72. Hog Cholera. Reynolds 209

73. Hog Cholera. Reynolds 210



ILLUSTRATIONS xxi

FIG. f^«^

74. Hog Cholera. Eeynolchi 211

75. Hog Cholera. Hetjuolds 212

76. Foundercil Hoof. B. A. 1 225

77. Showing Whore to Tap for Bloat. Beynolds 230

78. Trocar and Cannula 231

79. Parturient Paralysis. Reynolds 233

80. Parturient Paralysis. Ecynolds 234

81. Parturient Paralysis. Beynolds 235

82. Wire for Relieving Choke. Beynolds 239

83. Ringbones. Beynolds 243

84. Sidebones. Beynolds 243

85. Spavins (Two Types). Reynolds 244

86. Navicular Disease. Beynolds 247

87. Generative Organs of the Mare. Fleming 254

88. Fetus and Fetal ^^lenibranes of the Cow at Mid-pregnancy.

Fleming 255

89. Bovine Cotyledons. Fleming 256

90. Presentations. B. A. 1 275

91. Holding Horse's Head for Drenching. Reynolds 281

92. Throwing Cattle. Beynolds 291

93. Restraint for Castration. White 292

94. General View of Scrotum and Sheath. White 292

95. A Good Type of Emasculator. White 293



VETERINARY STUDIES




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VETERINARY STUDIES



LECTURE I

ANATOMY

Anatomy is the science which treats of forms, structures,
and relations to body organs. These org-ans are divided
for study into groups as follows: bones, muscles, joints,
nervous system, circulatory apparatus, respiratory apparatus,
urinary apparatus, digestive apparatus, and reproductive ap-
paratus.

Osteology, Bones

Kinds.— Bones are classified as long, short, flat, and irregular.

Long hones are more or less elongated in form and have a mar-
row-filled canal in the shaft, example— humerus, femur, radius,
and tibia. They are used in the legs as columns of support and
for levers pulled by muscles to produce motion.

Short bones are usually short in form, and have no medullary
canal. Examples of this class are carpals and tarsals. They are
used, for example, in the knee and hock where complicated artic-
ulation is needed with ability to stand pressure.

Flat hones, like those of the skull and the ribs, consist of two
plates of hard bone tissue connected by porous bone. They are
used to enclose and protect vital organs and to provide muscle
anchorage.

Irregular hones are usually found in the median line of the
body ; example, vertebrae. These are adapted for weight support
and muscle anchorage.

Peculiarities. — Terms used in describing and recognizing bones
are: elevations, depressions, borders, surfaces, angles, and ex-
tremities.

Development. — Bones develop around centers of ossification
(bone formation) either in cartilage or membrane. Long bones
develop from cartilage; the flat bones develop from membrane.

1



2 VETERINARY STUDIES

Bones grow in diameter by the production of new bone cells at
the inner surface of the periosteum. They grow in length by the
development of bone cells in a cartilage matrix between centers
of bone formation in the shaft and extremities of the bone. A
long bone, for instance, may have three centers of ossification,
one in the shaft and one in each end, with a layer of this cartilage
matrix in the end between the centers of ossification. Bone cells
in the lacunas (spaces) throughout the substances of the bone,
prepare and deposit lime salts and other material.




Fig. 2. — Horse's Skull. (Chauveau.)

1, Premaxillary bone; 2, upper incisors; 3, upper canine teeth; 4, supe-
rior maxillary bone; 7, nasal bones; 8, lachrymal bone; 11, malar bone;
12, upper molar teeth; 13, frontal bone; 15, temporal bone; 16, parietal
bone; 17, occipital; 20, styloid processes; 24, parietal crest; 25, inferior
maxilla; 26, inferior molars; 28, inferior canine teeth; 29, inferior incisor



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