55.
UNIDETJTIFIED SPEAKER: I would l i k e t o ask D r . F o r r e s t - - a r e most
of t h e instruments t h a t you described c o m e r c i a l l y a v e i l a b l e , o r do yod have
t o b u i l d your own?
DR. F O m S T : The one t h a t I showed of D r . G r i s b y ' s i s comlerc i a l l y a v a i l a b l e . Mine was b u i l t on my own. It i s p r e t t y simple.
A. M. W I N S : The t a p e r e c o r d e r i s not working, and t h i s i s
being t a k e n down i n shorthand, so i f you have a q u e s t i o n , p l e a s e give your
name and i n s t i t u t i o n , s o we can i d e n t i f y you. Yes, i n t h e back?
CHARILE COOK, C e n t r a l Soya, Glen E l l y n , Ill.: I ' d like t o d i r e c t
a q u e s t i o n e i t h e r t o D a r r e l l or t o John. Do you have any evidence t h a t t h e
s e a r i n g of a c i d components of f o s s i l s can have any r o l e i n t h e p h y s i c a l
m a n i f e s t a t i o n i n t h e development of r i g o r ?
J. C . FORREST: I have no d i r e c t evidence, b u t i n some of t h e
measurements I have made of r i g o r mortis, p a r t i c u l a r l y r e c e n t l y when I used
i s o t o n i c s o l u t i o n s , I had t h e f e e l i n g t h a t t h e p l a s t i c component i s showing
up more t h a n I had noted i n experiments vhere I d i d not have f o s s i l s suspended i n a s o l u t i o n . It seems t h a t some of t h e l o s s of e l a s t i c i t y t h a t we
n o t i c e d w a s due t o drying, and I t h i n k Dr. Go11 has mentioned t h i s a l s o .
For i n s t a n c e , sometimes i n c e r t a i n muscles, w e can go t o t h e completion of
r i g o r m o r t i s and w e s t i l l f i n d e l a s t i c i t y i n t h e muscles, and t h i s must be
due t o t h e e l a s t i c component. Even though we are not having any change,
t h e r e i s s t i l l some e l a s t i c i t y l e f t .
DR. GOLL:
I have nothing t o add t o t h a t , except t o second your
i d e a about running experiments now i n i s o t o n i c s o l u t i o n s . I t ' s r e a l l y much
b e t t e r . Drying r e a l l y has a t t r i b u t e d t o a l o t of e f f e c t s which were d i f f i c u l t t o i n t e r p r e t before.
RONALD CROW; A r m o u r and Co. : I would l i k e to a d d r e s s a que s t i o n
t o D a r r e l l Goll--what you observed i n t h e Z - l i n e - - i s t h i s repeatEble, o r i s
t h i s j u s t a happenstance?
DARREL GOLL: W e can see it f r e q u e n t l y , but only a t h i g h e r temp e r a t u r e s . We i n our p a r t i c u l a r l a b o r a t o r y have been running experiments a t
Z0 or lo ( t h e s e are all c e n t i g r a d e temperatures I am t a l k i n g about) and 1
6
'
,
25O, and 37'.
W e see it a t 25' and 37'--we've
never seen it a t '
1 or 1
6
'
.
You can see it i n maybe 10% of t h e f i e l d s you view under t h e e l e c t r o n
microscope. You w i l l see what looks l i k e Z - l i n e m a t e r i a l s . I t h i n k
t h e p a r t i c u l a r s l i d e I showed, or at l e a s t t h e i n s e r t , i s our b e s t o r
c l e a r e s t diagram. There i s no r e a s o n t o t h i n k t h e s e would be l y i n g i n
c r o s s - s e c t i o n so t h a t you could s e c t i o n them off anyway. The s t r u c t u r e you
s a w i n t h e i n s e t i s c l e a r l y not a c r o s s s e c t i o n of my0 f i b e r s . It i s not
anybhing l i k e what myo f i b e r s look l i k e i n c r o s s s e c t i o n .
A. M. MULLINS: If t h e r e are no f u r t h e r q u e s t i o n s from t h e f l o o r ,
I should l i k e t o ask a q u e s t i o n of D a r r e l o r anyone of t h e s e gentlemen who
would c a r e t o answer it. We have been t , a l d f o r a number of y e a r s t h a t
t e n d e r n e s s i s an i n h e r e n t c h a r a c t e r i s t i c . Would you c a r e t o expound on how
t h i s g e n e t i c i n f l u e n c e i s being manifested?
56.
H . K. HERRING: I f it i s manifested, it i s very subtle t o m e . I
would t h e o r i z e t h a t it would be more t o t h e connective t i s s u e components
t h a n t o t h e f i b r i l l a r components. This could be r e f u t e d by our riiork with
t e n d e r n e s s c l a s s i f i c a t i o n of t e n d e r and tough n u s c l e s and t h e p r o p e r t i e s of
actomyocin from t h e s e c l a s s i f i c a t i o n s . I t ' s probably up i n t h e a i r .
PAUL GOESER from Swift: If w e accept t h a t , t h e n you have a l i t t l e
t r o u b l e i n t r y i n g t o e x p l a i n what we apparently have found. If you t a k e cov
c a r c a s s e s of a t o p Commercial Grade, t h e r e w i l l be some percentage, around
3 t o 5$, t h a t 24 hours a f t e r death w i l l be completely t e n d e r - - x t e n d e r as
you can expect any aged p i e c e of beef t o be. Now t h i s occurs and t h e r e i s
j u s t a s u b t l e d i f f e r e n c e e i t h e r g e n e t i c a l l y o r i n t h e nanner i n which some
c a r c a s s e s do go through t h e whole of t h e r i g o r . They have a very f a s t
r e s o l u t i o n of r i g o r . If it were p o s s i b l e t o i d e n t i f y t h e s e c a r c a s s e s ,and
had time, it would g i v e you an opportunity i n t h e t y p e of work which you zrc
doing now t o have checked them and t o know wherein t h e y d i f f e r from c a r c a s s e s t h a t go through r i g o r r e s o l u t i o n and do not come out t e n d e r .
A. M. W I N S : Thank you, D r . Goeser. Any f u r t h e r comment on
This prompts another question, and I w i l l ask t h e question, and t h e n
Darrel can g e t up and expound on t h e question of D r . Goeser. C e r t s i n l y
D r . B e n d a l l ' s r e c e n t work i n England on t h e molecular s t r u c t u r e of connect i v e t i s s u e e x p l s i n s a l o t of t h e t e n d e r n e s s rates t h a t he encountered i n
many of t h e muscles he w a s studying. I have r e f e r e n c e h e r e i n t h e c r o s s
l i n k a g e s i n t h e c o l l a g e n f i b e r s . Perhaps t h i s a s s o c i a t i o n has been e v i d e n t
w i t h i n c r e a s i n g age, because we know t h a t t h e c r o s s l i n k a g e s i n c o l l a g e n
f i b e r s are increased w i t h i n c r e a s i n g age; but sometimes t h e mature animals,
Dr. Goeser h a s pointed out, are v e r y t e n d e r ; so my q u e s t i o n i s j u s t how much
can we a t t r i b u t e t e n d e r n e s s t o t h e state of t h e c o n t r a c t i l e p r o t e i n s and how
much of it i s due t o t h e molecular state of t h e connective t i s s u e s ?
that?
DAWiEL GOLL: I shouldn't be t h e one answering t h a t , because I
t h i n k Harold h a s done t h e work on t h a t , b u t I subscribe t o H a r o l d ' s t h e o r y
t h a t both are involved--the connective t i s s u e and t h e c o n t r a c t i l e p r o t e i n s .
I t h i n k we can p r e t t y w e l l a t t r i b u t e t e n d e r n e s s t o t h e s e two f a c t o r s ; and i n
muscles where t h e r e i s a l o t of connective t i s s u e and where it i s h i g h l y
c r o s s l i n k e d , I t h i n k t h e connective t i s s u e f a c t o r may be t h e predominant
one.
I w a s j u s t going t o comment on your e a r l i e r comment--I t h i n k t h e r e
i s nothing wrong w i t h seeing t h i s g e n e t i c r e l a t i o n s h i p t o tenderness, because all t h i s g e n e t i c f a c t o r means i s t h a t t h e s e p r o t e i n s a r e synthesized
from t h i s g e n e t i c message, and t h e r e i s no reason t o suppose t h a t t h e s e
p r o t e i n s a r e t h e n synthesized and assembled i n t h e same manner i n every
animal. We know t h e r e are g e n e t i c d i f f e r e n c e s , and not s o much of t h e prot e i n i s g r o s s l y d i f f e r e n t - - t h e y all have myocin and t h e y all have a c t i n .
The s u b t l e d i f f e r e n c e i s i n t h e myocin and t h e a c t i n , and t h e s e i n t u r n
cause s u b t l e d i f f e r e n c e s i n assembly. Perhaps t h e Z - l i n e i n some a r e not
assembled, and t h e s e a r e f e r t i l e areas for r e s e a r c h r i g h t now. There are
s u b t l e d i f f e r e n c e s i n t h e s e which we j u s t know nothing about as y e t . I
t h i n k t h e r e i s evidence f o r a r e a l g e n e t i c b a s i s , and I t h i n k t h i s j u s t
r e f l e c t s t h a t t h e s e connective p r o t e i n s are g e n e t i c a l l y somewhat d i f f e r e n t ,
s u b t l y different--something t h a t we d o n ' t see y e t .
57.
A. M. MULLINS:
Harold, do you want t o add anything?
HAROLD HERRING: No, I d o n ' t b e l i e v e so, except t o say t h a t it
has been shown t h a t i n c r e a s e d c r o s s l i n k i n g does occur with animal aging,
and t h i s can be a s s o c i a t e d with t e n d e r n e s s . If you go w i t h i n a particular
m a t u r i t y group i n animals, you can f i n d no r e l a t i o n s h i p of t h e c r o s s
l i n k i n g of c o l l a g e n , f o r example, with t e n d e r n e s s , so it depends on how you
r u n your study, and how you d e f i n e your population.
A. M. MULLINS: Thank you very much. O u r t i m e i s running out--we
are a l i t t l e over t i m e . Again, I c e r t a i n l y want t o commend t h e speakers on
t h e manner i n which t h e y handled t h e s u b j e c t which w a s assigned t o them, and
c o n g r a t u l a t e you on your a t t e n t i v e a t t e n t i o n and on your p a r t i c i p a t i o n i n
t h e d i s c u s s i o n . With t h i s I w i l l t u r n it back t o our chairman, D r . R . B.
Sleeth.
R. B. SLEETH: Thank you very much, A u t t i s ; I ' m s o r r y t o c u t down
on t h i s very f i n e d i s c u s s i o n . I ' m sure you would l i k e a t break t i m e t o
continue t h e d i s c u s s i o n with t h e speakers. Our a p p r e c i a t i o n t o you, Paul,
and t o your speakers for an e x c e l l e n t p r e s e n t a t i o n and program. I t h i n k
without q u e s t i o n t h i s sets t h e t e n o r f o r an e x c e l l e n t program t o f o l l o w .
We are running approximately t h i r t y minutes behind schedule. We
had twenty minutes scheduled f o r you t o s t r e t c h and do anything e l s e you
might need t o do, s o would you see i f you could be back at 10:45 promptly,
p l e a s e ? Thank you.
Because many of you have not p r e v i o u s l y v i s i t e d t h e U n i v e r s i t y of
Georgia campus and t h e f a c i l i t i e s t h a t t h e y have a v a i l a b l e here f o r t e a c h i n g
and r e s e a r c h , we thought it would be w e l l t o , i n advance of t h e t o u r t h a t we
w i l l have tomorrow have a b r i e f d i s c u s s i o n by a member of t h e Food Science
Department and t h e Animal Science Department t o l e t you know a l i t t l e b i t
about t h e t o t a l program and t h e o v e r a l l emphasis t h a t i s placed i n t h e
r e s p e c t i v e areas.
A t t h i s t i m e we w i l l ask D r . Bob S a f f l e , who has c e r t a i n l y done a
yeoman's job i n making all t h e arrangements and c o o r d i n a t i n g t h e arrangements f o r t h i s program, who i s a member of t h e staff of Food Science, and
whose l a t e s t n o t o r i e t y t o fame i s t h e f a c t t h a t he h a s now found t h a t he can
add 103% of f a t t o frankfurters; s o we w i l l ask him t o come and e x p l a i n t o
you what i s going on i n t h e Food Science Department.
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