Page 115 - Anatomy and Physiology of Farm Animals, 8th Edition

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Tuberculosis of bone and osteomyelitis any abnormality in bone development.
Osteodystrophy is a general term for
(inflammation of the bone and bone
VetBooks.ir marrow) are two infections sometimes Many osteodystrophies are due to some
abnormality in the normal regulation of
seen in bone. In humans, bacterial osteo-
myelitis usually is caused by Staphylococcus calcium and phosphorus. The abnormality
sp. or Streptococcus sp. that gain access to could be produced as a result of an
the bone by way of the bloodstream and inappropriate diet or some disease state
develop into a general infection, or by way disrupting calcium and phosphorus
of a wound, in which case the infection regulation.
may remain local. Rickets in young, growing animals and
Benign (slow‐growing, noninvasive, osteomalacia in adults are conditions of
and not likely to cause death) bone tumors inadequate mineralization of osteoid.
are named according to the cells of bone Without appropriate mineralization, bones
from which they originate. A tumor of are relatively weak and flexible. Both rick-
bone tissue itself is called an osteoma. ets and osteomalacia usually are due to a
Chondromas may develop from the epi- lack of vitamin D, which is required for
physeal cartilage or from unabsorbed normal absorption of calcium from the
islands of cartilage that preceded the gastrointestinal tract. However, they may
developing bone. Tumors develop and also be caused by an imbalance or lack of
grow as a result of intrinsic changes in the calcium and/or phosphorus in the diet.
cells of origin, but bony growths may also Rickets chiefly affects the growing areas in
occur on the surface of a bone simply in bone, while osteomalacia, sometimes
response to prolonged irritation. Such called adult rickets, affects the entire bone,
growths are called exostoses. since there are no rapidly growing areas in
Malignant tumors grow rapidly, metas- adult bone.
tasize (spread to other locations), and are Achondroplasia is a hereditary condi-
often fatal if not treated. Osteogenic sarco- tion in which the metaphyses fuse early in
mas are malignant tumors of bone that life, but the bones continue to increase in
most commonly develop near the ends of diameter. An animal affected with it is
long bones. Sarcoma is a general term for called an achondroplastic dwarf. The
malignant tumors originating from tissues dachshund is a breed of dogs selectively
of mesodermal origin, such as connective bred for this condition. Dwarfism in cattle
tissue. closely resembles achondroplasia.