Deep Pectoral Myopathy: A Penalty of Successful Selection for Muscle Growth

Abstract

Deep pectoral myopathy (DPM) is a disease that affects commercial poultry selected for large breast muscle development. The muscle affected by the disease is the supracoracoid muscle and usually one side of the breast musculature atrophies. The necrotic muscle has a characteristic pale green color. Heavy breeds of turkeys and broilers can be induced to show DPM by electrical stimulation of the breast muscle itself or by vigorous wing flapping; older birds are more susceptible. The cause of DPM is a fascial compartment too small to accommodate the enclosed supracoracoid muscle during vigorous exercise when the muscle increases its weight (and overall size) by about 20%. The inelastic compartment essentially strangulates the swollen, activated muscle. A possible means of correcting DPM is to train or exercise the flight muscles during the rapid growth phase of chicks or poults. Feed, for example, could be positioned above floor level so that birds would have to flutter up to reach it. There is also evidence to suggest a genetic component to the disease. Hence, an indicator such as high plasma creatine kinase levels may be used as a selection criterion.

Deep Pectoral Myopathy (DPM) in broiler chickens

“…Moreover, peripheral to the necrotic regions the musle fibres were oedematic and their sarcoplasma was shrunk. These alterations indicate ischaemic necrosis and agree with the reports of other researchers (Page and Fletcher, 1975, Richardson et al 1980, Siller 1985, Wilson et al 1989). …”

“…Επιπλέον, στην περιφέρεια των περιοχών με νέ κρωση, οι μυϊκές ίνες ήταν οιδηματικές, με συρρικνω μένο το σαρκόπλασμά τους. Οι αλλοιώσεις αυτές είναι ενδεικτικές ισχαιμικής νέκρωσης και συμφωνούν με τις αναφορές άλλων ερευνητών (Page and Fletcher 1975, Richardson et al 1980, Siller 1985, Wilson et al 1989). …”

Dilemmas of Limitation of DPM-Type Pectoral Muscle Myopathy in Broiler Chickens

“…"syndromem przestrzeni" (ang. compartment syndrom) [24]. Mięsień piersiowy mniejszy otoczony jest kością kruczą i mostkiem oraz bardzo mocną, nieelastyczną powięzią, oddzielającą go od mięśnia piersiowego większego.…”

“…W konsekwencji, długo utrzymujące się ciśnienie prowadzi do martwicy niedokrwiennej, w tym przypadku zatrzymania dopływu krwi do mięśnia. W wyniku tego następuje niedotlenienie tkanek i pojawiają się objawy ich obumarcia, czyli nekroza [3,24].…”

The effect of a housing system in slaughter turkeys on mechanical damage to carcass and meat quality

“…Turkey selection for fast growth, high feed conversion ratio and high body weight results in the imbalance between the muscle growth rate and their physiological capacity (Siller, 1985;Sosnicki and Wilson, 1991). Any stress experienced by birds during their life and pre-slaughter handling can disturb the transformation processes occurring in muscles a�er slaughter (Henckel, 1992).…”