POULTRY PUNCH - FEBRUARY 2019

ARTICLE NEWS
Musculoskeletal disorders lead to lameness
in birds an overview
1Maneesh Sharma, 2Shagufta Azmi and 3Nabjot Singh Risum
1Assistant Professor, Division of Veterinary Pathology, Arawali Vety. College, Sikar, Rajasthan;2 Professor,
Division of Veterinary Pathology, SKUAST, Jammu and 3Veterinary Officer, Military Dairy Farm, Jammu
With the advancement of science and technology, so many new techniques are adopted to increase the production
level of chicken meat and eggs. The problems of skeletal abnormalities may arise becauseof the birds put on weight faster
than they build their bone structure to support the weight. Production characteristics of modern poultry lines (body weight in
broiler chickens, egg production in laying hens) place high demands on the skeletal system, and inadequacies in nutrition
or husbandry often result in skeletal disorders. They may be primarily infectious or non-infectious; both may be seen
concurrently within a flock. Skeletal disorders cause lameness from biomechanical dysfunction. Lameness is a growing
problem in modern poultry and one of the significant causes of mortality in broilers. Lameness will cause birds to suffer and
limit their natural movements that results in reduced feed and water intake.
Leg disorders and lameness adversely affect the performance and well-being of birds while increasing morbidity
and mortality, which cause significant economic losses to the poultry industry.
Causes
A. Developmental deformities
a. Genetic and Congenital (Developmental) Anomalies: Many skeletal abnormalities are seen in embryos when
unhatched eggs are broken out. Limb deformity and torticollis are seen occasionally in chicks in the hatching trays. These
defects may be genetic or congenital and congenital defects may have a metabolic origin. Scoliosis and kyphosis are
more frequently occurs. Birds with torticollis have difficulty eating. Scoliosis does not usually cause a problem but may be
associated with increased valgus-varus deformity.
b. Acquired defects:
1) Crooked toes; curled toes: Curled toe is a common developmental anomaly in both young growing birds, affecting a
few birds in most flocks. Toes are bent either laterally or medially in a horizontal plane. Examination reveals twisting of
the phalanges. Infrared brooding and wire floors appear to increase the incidence. This condition must be differentiated
from curled toes due to riboflavin deficiency in young birds, in which the toes are curled ventrally and in which the
primary lesion is in the peripheral nerves.
2) Slipped tendon: The gastrocnemius tendon has slipped off the condyles of the distal tibia and the bird has lost control
of the lower leg. Primary slipped tendon can occur without bone or cartilage abnormality and is not necessarily caused
by manganese or other deficiency. Bone strength is normal. Slipped tendon causes only 1-3% of the lameness in
chickens. It is rare in poults.
88 February, 2019