Basic HTML Version
International Journal of Molecular Veterinary Research
2013, Vol.3, No.5, 13-22
http://ijmvr.sophiapublisher.com
18
vitamin D could be a cause.Canine Distemper virus
RNA was detected recently within the bone cells of
dogs with HOD suggesting a role for this virus in
etiopathogenesis (Mee, 1993). It has also been seen
that dogs inoculated with the blood from the dogs with
HOD developed Distemper (Johnson et al., 1995).
Schulz et al. (1991) detected
E. coli
bacteraemia in a
6-month old intact male Great Dane that had
hypertrophic osteodystrophy. Most animals the
animals develop clinical signs during first 6 months of
age (Meier et al., 1957; Watson et al., 1973 and
Grondalen, 1976), which include slight limp, pain on
deep digital palpation of the affected metaphyses,
anorexia, weight loss, variable pyrexia, swollen, warm
and painful long bone metaphyses; with refusal to
bear weight on the affected limbs (Newton, 1985).
(Meier et al., 1957; Holmes, 1962; Watson et al.,
1973). Clinical signs often subsided after a few days
and recurred after number of days. Other clinical sign
was haemorrhage in various sites, especially visible in
gingivae (Schalm, 1965 and Morris, 1968).
3.5 Radiographic changes
Radiographic changes in the early stages of HOD
occur in the metaphyses of the long bones and are
usually bilaterally symmetric. (Newton, 1985). A
radiolucent zone in the metaphysis parallel to the
epiphyseal plate was most evident in the distal radius
and ulna (Grondalen, 1976). Some times a radiodense
line was seen adjacent to the epiphyseal plate (Watson
et al., 1973). Surrounding soft tissue might be swollen.
Later radiographs might show metaphyseal
enlargement with irregular periosteal new bone
formation although not all affected dogs developed
those changes.
Haematological and biochemical tests contribute little
to the diagnosis, although neutrophilia, monocytosis
and lymphocytopenia could occur during active
disease, reflecting stress and inflammation (Johnson et
al., 1995). Haematobiochemical parameters were
estimated by Grondalen (1976) in 26 growing dogs.He
found microhaematocrit values between 32% and 42%
in 14 dogs (normal 37.0~55.0; Schalm, 1965),
increased ESR in 13 dogs, hemoglobin (g/dL)
between 9.8~14.6 in 13 dogs, total erythrocyte count
between 3.2 and 8.0 m/mm3 in 13 dogs and total
leukocyte counts were 19000 m/mm
3
. DLC in
fourteen dogs showed no abnormalities. Blood
calcium was 7~11.5 mg/dL and phosphorus was
4~14.5 mg/dL in 17 dogs. Serum ascorbic acid (SAA)
was found between 0.4~4.6 mg/dL in 18 dogs and
serum alkaline phosphatase measured 0.5 and 18.9
Bessey Lowry units in 16 dogs.
4 Developmental Causes
4.1 Retention of endochondral cartilage
Retention of endochondral cartilage occurs in young,
large and giant breed dogs (Riser and Shirer, 1965,
and Johnson, 1981). Any long bone may be involved;
however, the distal ulna is most frequently affected
(Burk and Ackerman, 1986). Johnson (1981) reported
that disturbance in endochondral ossification of the
growth plate lead to retained cartilage core, which is
responsible for the development of forelimb deformity.
In retained cartilage core, physeal hypertrophic
chondrocytes fail to mature and mineralize the
adjacent matrix and they accumulate in long columns
in the primary spongiosa. Clinical signs in dogs with
retained cartilage included growth retardation,
intermittent lameness and lateral angulation of the foot
(carpal valgus) (Burk and Ackerman, 1986). The
condition usually affects both limbs in a similar
manner. Retarded ulnar growth causes relative
shortening of ulna, valgus and rotation of the paw,
cranial bowing of the radius and carpal, and elbow
subluxation (Johnson et al., 1995).
4.2 Radiographically
Radiographically, cases of RCC showed inverted
radiolucent cone extending proximally from the distal
ulnar physis into the metaphysis. Irregular
metaphyseal radiolucencies and physeal widening
might be observed in other bones (Burk and
Ackerman, 1986). Irregular patterns of metaphyseal
bone density might persist after maturity.
5 Medicinal Management of Angular Limb
Deformities
5.1 Vitamins and minerals
Rickets in a litter of racing greyhound pups were
treated by feeding diet containing 1.3% calcium,
1.00% phosphorus and 1860 IU vitamin D/kg of food
(414 IU/1000 Kcal metabolisable energy), 3-4 times a