Hệ thống xương khớp trên gia cầm

1 Pathology Pathology of of the the locomotor locomotor system system Skeletal system Pathology Pathology of of the the bones bones • Transformation of the vertebrae and bones • Osteopathies – abnormalities of the osteogenesis • Disturbances of the mineralization • Regressive changes of the bones Transformation of the vertebrae Transformation of the vertebrae and bones and bones • Spondylolisthesis • Tibiarotation • Twisted leg syndrome • Spread leg syndrome Transformation of the vertebrae Transformation of the vertebrae • Spondylolisthesis – devolution of the vertebra – and tilting at the same time Anatomy • functional anatomy – The spinal column is parallel with the ground in a newly hatched chick on the first day – the physiological lordosis develops on the first week – and so does the position, pose typical for the species Photo: Dr. Dobos-Kovács, Mihály Spondylolisthesis Spondylolisthesis ( ( devolution devolution of of the the vertebra vertebra ) ) • The chicks develop fastest in the first 3 weeks of age – The pectoral muscles grow considerably – later it is even more explicit • the large pectoral musculature…. – pulls the 6. thoracic vertebra and moves it from its normal position…. – The spinal column suffers refraction at the level of the 6th vertebra…. 2 Photo: Dr. Dobos-Kovács, Mihály Spondylolisthesis Spondylolisthesis ( ( devolution devolution of of the the vertebra vertebra ) ) During walking • from the direction of the hind legs • power acts forward and downward – On the previously tilted vertebra • the back of the vertebra moves – up and forward • the front of the vertebra moves – down and backwards • the 6. thoracic vertebra moves downwards – slips (devolution) • and tilts from its original pose Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály Spondylolisthesis Spondylolisthesis ( ( devolution devolution of of the the vertebra vertebra ) ) • Typical lesion in large meat type chicken hybrids with huge pectoral musculature – affects smaller or larger part of the flock – husbandry problems (keeping and nutrition factors) are also involved • The 6th vertebra which moved from its original position… – compresses the ventral part of the spinal cord – Waller-degeneration occurs in the motoric nerve tracts – weakness and paralysis develops in the hind legs • consequences: • the affected animals first limp, later are not able to move – no drinking (uricosis) – exsiccosis – starving to death Photo: Dr. Dobos-Kovács, Mihály 3 Transformations Transformations of of the the spinal spinal column column • Lordosis – the spinal column bends up • Kyphosis – the spinal column bends down • Scoliosis – the spinal column bends in S shape Transformations Transformations of of the the spinal spinal column column • In case of spondylolisthesis – and during spondylosis too • pain occurs – due to the compression of the spinal cord • and due to the compression of the nerve tracts too • The bird tries to reach the less painful pose (position of the spinal column) – in most cases immediately gets paralyzed • The abnormal pose of the spinal column – ossifies soon and gets fastened – according to the abnormal, but less painful position! Scoliosis Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály Transformation Transformation of of the the bones bones • Tibiarotation – the tibiotarsal bone gets twisted around its longitudinal axis – usually turns laterally • 45-90-180° – the distal part of the join turns with – and so does the lower part of the leg – The joint turns too The tendon follows the joint, it remains in the pit!!! • Twisted leg syndrome • Spread leg syndrome Photo: Dr. Dobos-Kovács, Mihály 4 Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály Tibiarotation Tibiarotation • The cause is not known – genetic predisposition? – malnutrition? – husbandry problems? • Increasingly often seen in young poult – according to field experiences – malsecretion maldigestion and malabsorption increases the possibility of the lesion – in young age • Rickets is the predisposing factor in guinea fowl chicks for the tibiarotation Twisted leg Twisted leg syndrome syndrome • The disease starts with the lateral or medial rotation of the distal part of the tibiotarsal joint – the leg follows the turning part of the joint with the tarsal bone – the distal part of the leg turns out or in together with the tibiotarsal joint – It looks like the joint was twisted • Diagnosed in broiler chicken and turkey Twisted leg Twisted leg syndrome syndrome • The pathogenesis is not cleared yet • The appearance of the syndrome increases with the appearance of new genetic lines in broiler chicken and turkey industry • It highlights the predisposition of the modern hybrids towards this condition 5 Spread Spread leg leg syndrome syndrome • The legs are spread to the side or to the back – the legs turn from the coxofemoral joint – it can occur uni- or bilateral • Causes – not clear – high humidity during hatching? – according to observations it develops in newly hatched birds on slippery floor • In some cases the lesion develops only in 2-3 weeks old birds Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály Osteopathies Osteopathies • Several different substances are needed for the normal development of the bones – In case some materials are not available in proper amount, typical lesions develop in the bones • Forms: – Osteopathy due to lack of vitamin D3 (rickets) – Osteopathy due to lack of calcium • Rickets due to Ca deficiency – Osteopathy due to lack of phosphorus • rickets due to P deficiency – Osteopathy due to lack of proteins – Osteopathy due to lack of vitamins – Osteopathy due to lack of minerals – Osteopathy due to lack of viral infection – Other osteopathies Osteopathy due to lack of Osteopathy due to lack of vitamin D3 (rickets) vitamin D3 (rickets) • this is the original disease – lack of sunshine – not enough vitamin D was produced in the skin – vitamin D supply was not enough for the animal • the original meaning of the disease: – rickets is the incomplete development and ossification of the growing bones • incomplete development and ossification of the growing bones due to lack of vitamin D – there is enough Ca and P in the feed – no vitamin D3, no transport proteins are produced which are eccential for the Ca absorption from the gut • In broader meaning: – Besides the rachitis caused by lack of vitamin D – We call rickets the osteopathies due to lack of Ca- and/or P!!! • In case of rachitis lesions develop in all growing bones • Most important to check – The long bones, the ribs and the sternum Rickets Rickets • In the long bones of birds – enchondral ossification is examined in the proximal epiphysis • The parts of the proximal epiphysis: – Epiphyseal cartilage – Proliferation zone • production of cartilage • necrotizes and calcification occurs – Growth zone • With the active bone marrow • resorption of the calcified cartilage • new bone replaces the cartilage Photo: Dr. Dobos-Kovács, Mihály 6 Rickets Rickets due due to to lack lack of vitamin D of vitamin D or or Ca Ca • In the deep layers of the epiphyseal cartilage new chondrocytes and cartilage is formed – later the chondrocytes necrotize and the cartilage calcifies – active bone marrow intrudes into that layer – and it resorps the necrotized and calcified cartilage • Production of new bone tissue – At the beginning osteoid is formed – This calcifies – 1:9 - Ca-carbonate and Ca-phosphate – + small amount of Mg-phosphate and calcium-fluoride • In case of rickets due to lack of vitamin D3 in the long bones – epiphyseal cartilage is produced – The other processes are slower or do not floolw the cartilage prodution • So the epiphyseal cartilage becomes thicker – The cartilage extends due to the bodyweight – The end becomes butt, and painful, the bone bends Photos: Dr. Dobos-Kovács Mihály Rickets Rickets due due to to lack lack of of Ca Ca Photos: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály 7 Photo: Dr. Dobos-Kovács, Mihály Felvétel: Dr. Dobos-Kovács Mihály The The bone bone can can be be broken broken without without sound sound • There is constant ossification and the depots are used up • The compacta of the bone becomes thinner and the bone is spongy – juvenile osteoporosis Rickets Rickets due due to to lack lack of P of P Photo: Dr. Dobos-Kovács, Mihály Osteopathies Osteopathies • Osteopathy due to lack of proteins – Lack of amino acids • Lysine – hypoplastic type of bones are produced • Osteopathy due to lack of vitamins – Lack of vitamin C – Lack of nicotinic acid • vitamin B5, niacin • rickets-like lesions – Lack of vitamin A 8 Osteopathy due to lack of vitamins Osteopathy due to lack of vitamin C • the malfunction of the mesenchymal cells • because of their fatty infiltration – cartilage and osteoid production – deceased production of the basic substance • no problem with the calcification Osteopathy due to lack of vitamin niacin (rickets-like lesion) • the lesions are similar like in case of osteopathy due to lack of P • in geese Osteopathy due to lack of vitamin A • the enchondral ossification is decreased – In some case the skull and the vertebrae are also affected Osteopathy due to lack of Osteopathy due to lack of minerals minerals • Osteopathy due to lack of manganese (Mn) – perosis • the Achilles-tendon slips from the sulcus to the side • the distal end of the leg turns lateral – appears in young chicks and poult – rarely in pheasant and other birds • Osteopathy due to lack of zinc (Zn) – Zn is essential to the development of the skeleton • when Zn is missing, the lesions appear in the distal epiphysis of the tibia Perosis Perosis • Osteopathy due to lack of Manganese (Mn) – this lesion is mainly seen in case inadequate amount of manganese is available – but lack of other substances can also induced similar lesions • pyridoxine (vitamin B6) • biotin (vitamin B7 or H) • nicotinic acid (vitamin B5 or niacin) • folic acid /folacin/- (vitamin Bc or M) • choline (vitamin B komplex) – alone or in combination • the manganese influences the enchondral ossification – the extracellular substance (the matrix) of the cartilage is produced in decreased amount Perosis Perosis • In a classic case the lateral part of sulcus tendinis at the distal end of the tibiotarsal bone grows slower – the lateral part becomes shorter – the Achilles-tendon can easily slip to the lateral side – the distal end of the leg turns out • because of these processes – the distal end of the tibiotarsal bone is more smooth then normally – the sulcus and the bone condyles are flat Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály 9 Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály Osteopathy Osteopathy due due to to lack lack of of Zn Zn • The lateral epyphyseal cartilage grows and ossifies faster then the medial – The distal epyphisis of the tibia bends inward – the Achilles-tendon slip to the middle from the sulcus tendinis Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály 10 Photo: Dr. Dobos-Kovács, Mihály Photo: Dr. Dobos-Kovács, Mihály Osteopthies Osteopthies caused caused by by viruses viruses • Short beak and dwarfism syndrome of mule duck – SBDS • Mulard = pekin duck ♀ x Muscovy duck ♂ hybrid, „mule duck” • Pathogenesis – the mulard ducklings develop slowly and heterogenously • from young age already – Lack of development shows on the bones of the beak and tarsus • the beak becomes shorter then normally, the head is deformed • looks like the beak and head of goose – the tongue grows normally, so it hangs out from the beak – and dries out on the air – the animals look smaller, underdeveloped • because of the shortness of the tarsus Photo: Dr. Palya, Vilmos Photo: Dr. Palya, Vilmos Other Other osteopathies osteopathies • Lack of salt – the waterfowl are very sensitive • especially duck – In NaCl (table salt, especially natrium) deficency rickets-like lesions develop • similar to osteopathies due to lack of Ca and vitamin D • the proliferation zone of the epiphyseal cartilage becomes thicker • the osteoid tissue is not properly calcified, and the matrix is less