J. Anim Sci.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Taylor, R. G.
Right arrow Articles by Koohmaraie, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Taylor, R. G.
Right arrow Articles by Koohmaraie, M.

Journal of Animal Science, Vol 76, Issue 11 2811-2817, Copyright © 1998 by American Society of Animal Science

JOURNAL ARTICLE

Effects of postmortem storage on the ultrastructure of the endomysium and myofibrils in normal and callipyge longissimus

R. G. Taylor and M. Koohmaraie
SRV INRA de Theix, St. Genes Champanelle, France.

These experiments were conducted to examine ultrastructural changes in longissimus from normal and callipyge lamb during 14 d of postmortem storage at 4 degrees C. Six crossbred ewe lambs (1/2 Dorset x 1/2 Romanov) were grain-fed and slaughtered at approximately 250 d of age. Leg conformation score was the basis for classifying carcasses into normal and callipyge. The normal and callipyge longissimus had mean Warner-Bratzler shear force of 2.8 (2.7, 2.4, and 3.4) and 9.0 (12.2, 6.9, and 7.9) kg, respectively, after 14 d of postmortem storage. The results of transmission electron microscopy demonstrated ultrastructural changes, including sarcolemma detachment, loss of myofibril lateral attachments, and I-band breaks in normal longissimus. Detachment of sarcolemma from myofibrils occurred in both phenotypes, but it was delayed by several days in callipyge longissimus. Thus, the sarcolemma detachment seems not to contribute significantly to postmortem tenderization. The endomysium of both phenotypes did not change with postmortem storage. In normal longissimus, the percentage of fractured I-bands increased from 0% at d 1 to 11% at d 3 (P<.05) and did not change between 3 and 14 d (15%) postmortem (P>.05). However, postmortem storage did not affect (0 to 3%) the frequency of the I-band breaks in the callipyge longissimus (P>.05). Therefore, the break in the I-band region in postmortem muscle is a change that is associated with postmortem tenderization. We conclude that the major factor responsible for the toughness of meat from callipyge longissimus is the postmortem stability of myofibrils.


This article has been cited by other articles:


Home page
 J ANIM SCIHome page
G. H. Geesink, R. G. Taylor, and M. Koohmaraie
Calpain 3/p94 is not involved in postmortem proteolysis
J Anim Sci, July 1, 2005; 83(7): 1646 - 1652.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1998 by the American Society of Animal Science.