T h e o r e t i c a l a n d A p p l i e d G e n e t i c s 46, 3 3 - 4 3 ( 1 9 7 5 ) 9 b y S p r i n g e r - V e r l a g 1975

Variability of Intermuscular Bones, Vertebrae, Ribs, Dorsal Fin Rays and Skeletal Disorders in the Common Carp* Rom Moav and A. Finkel D e p a r t m e n t of G e n e t i c s , T h e H e b r e w U n i v e r s i t y of J e r u s a l e m , and G. Wohlfarth Fish and Aquaculture

Research

Jerusalem (Israel)

Station, Dor(Israel)

S u m m a r y . T h e n u m b e r of i n t e r m u s c u l a r b o n e s , v e r t e b r a e , r i b s , d o r s a l f i n r a y s a n d a n i n d e x of b o n e d i s o r d e r s w e r e d e t e r m i n e d f r o m x - r a y p h o t o g r a p h s of o v e r 1000 c o m m o n c a r p . T h e s e c a r p r e p r e s e n t e d a b r o a d g e n e t i c r a n g e , i n c l u d i n g f i v e d i s t i n c t l i n e s of t h e d o m e s t i c a t e d E u r o p e a n c a r p , o n e g r o u p o f t h e C h i n e s e r a c e Big-Belly a n d 12 c r o s s b r e d s . The genetic, and even the phenotypic, variation in intermuscular bones were much smaller than those found in earlier experiments. Variation of other bone chara c t e r s w a s a l s o a n a l y z e d a n d t h e r e l a t i o n s h i p of i n t e r m u s c u l a r b o n e s a n d r i b s t o v e r t e b r a e w a s d e t e r mined. c o m p o n e n t f o r IM b o n e s b y s t u d y i n g 8 f u l l - s i b f a m i l i e s b e -

Introduction The number of intermuscular many fish species,

bones has been counted in

either by cooking the fish and dissec-

ting out the intermuscular

(henceforth IM) bones (Lieder

1961a,b; Anwand, 1962; Kandler,197i;

Jahnichen, 1971;

J a h n i c h e n a n d B a l l , 1 9 7 2 ) , o r b y c o u n t i n g t h e IM b o n e s from x-ray photographs busch and Meske,

(v. Sengbusch,

1967; Meske,

A c c o r d i n g t o L i e d e r ( 1961 a , b ) , cimens,

1963; v. Seng-

1968; K o s s m a n n ,

1972).

w h o e x a m i n e d 11 s p e -

t h e n u m b e r o f IM b o n e s i n t h e c o m m o n c a r p i s

9 9 , w i t h a r a n g e of 95 t o 104. L i e d e r w a s a p p a r e n t l y t h e

b u t h e w a s n o t o p t i m i s t i c b e c a u s e of t h e s m a l l p h e n o t y p i c p h o t o g r a p h s of l i v e f i s h f o r w o r k of t h i s t y p e . K a n d l e r ( i 9 7 1 ) in

s t a r t i n g f r o m a b r o a d g e n e t i c ba@is carp,

a s t r a i n of t h e C h i n e s e r a c e (Big-Belly), t h r e e i n t e r - r a c e F 1 crossbreds

and nine crossbreds

among the European

l i n e s . W e e x p e c t e d t o f i n d i n o u r p o p u l a t i o n s at l e a s t a s w i d e a r a n g e of IM b o n e s a s t h a t f o u n d b y K o s s m a n n . i.e.,

vertebrae,

bone disorders.

ribs,

dorsal fin rays and visible

O v e r 1000 f i s h w e r e p h o t o g r a p h e d ,

but,

e x p e c t a t i o n s , t h e r a n g e of v a r i a t i o n i n IM b o n e s

w a s far to n a r r o w to permit a selection p r o g r a m .

The Fish Stocks

T h e f i r s t w o r k e r to u s e l a r g e s a m p l e s

with the object

of s e l e c t i n g c a r p w i t h a r e d u c e d n u m b e r of IM b o n e s w a s v. Sengbusch ( 1963). He and his coworkers p h o t o g r a p h s of h u n d r e d s of c a r p ,

took x-ray

c o u n t e d t h e i r IM b o n e s

and found a relatively wide phenotypic variation (v. Sengbusch, 1967, v. Sengbusch and Meske, 1967, Meske,1968). i n o n e p o p u l a t i o n t h e y f o u n d a r a n g e o f 70 Kossmann

(1972) separated

Altogether

18 g r o u p s w e r e s t u d i e d . T h e s e i n c l u d e d s i x

c l o s e d l i n e s a n d 12 c r o s s b r e d s

n u m b e r of IM b o n e s r a n g e d f r o m 100 t o 102.

to 135 IM b o n e s .

i n IM b o n e s o f c a r p ,

i n c l u d i n g f i v e l i n e s of t h e E u r o p e a n d o m e s t i c a t e d

while in three wild carp (one

from the river Elbe and two from a lake in Turkey) the

For example,

In s p i t e of t h e

above results we decided to search for genetic variability

contraryto

variation that he found. He also stated the need for x-ray 76-84),

carp.

w i d e d i f f e r e n c e s b e t w e e n t h e f a m i l y m e a n s . In v i e w o f t h e

bones,

of IM b o n e s i n t h e c o m m o n c a r p b y s e l e c t i v e b r e e d i n g ,

four carp from Holstein,

domesticated

n a r r o w g e n e t i c b a s i s of h i s p o p u l a t i o n , h e found, r e l a t i v e l y

T h e x - r a y p h o t o g r a p h s s e r v e d to s t u d y s e v e r a l o t h e r

f i r s t to c o n s i d e r t h e p o s s i b i l i t y of r e d u c i n g t h e n u m b e r

f o u n d a m e a n n u m b e r of 80 IM b o n e s ( r a n g e :

l o n g i n g to t h e G e r m a n

a genetic

the following (Hulata et al.,

(Table 1). The lines were

1974; Moav et al.,

1964) :

( a ) Gold;, a n i n b r e d l i n e c a l l e d Gold w a s i n i t i a t e d w i t h m u t a n t Gold i n d i v i d u a l s ( h o m o z y g o u s r e c e s s i v e s )

found

in a fish farm in Israel in 1963. ( b ) Blue-Grey; a s e c o n d i n b r e d l i n e c a l l e d Blue-Gr~y was founded by individuals homozygous for the two recess i v e b o d y c o l o u r a t i o n m u t a t i o n s , Blue and Grey!. T h e s e were found in another fish farm in Israel in 1960. ( c ) Na~ice; a s e l e c t e d s t r a i n d e v e l o p e d i n t h e f i s h f a r m Na~ice in Yugoslavia,

* This research w a s supported by a grant f r o m the N a tional council for research a n d D e v e l o p m e n t of Israels's Government.

(Fijan,

a n d i n t r o d u c e d t o I s r a e l i n 1970

personal communication).

( d ) Holland-B; t h i s s t r a i n w a s i n t r o d u c e d t o I s r a e l

34

Rom

T a b l e 1. T h e g e n e t i c g r o u p s , Tested group

Moav

et al. : Variability

their parents and numbers

Parents

strains

of Intermuscular

1972 male

BB Gold Dor

(16) (16) (4) (19)

BB Nas BB

Nas Gold Dor

(16) (4) (14)

Nas Nas Nas

Gold Gold X Dor Gold x Blue

Gold Dor Blue

(4) (15 (5

Gold Gold Gold

Dot-70 (Dor)

Dor

(15

Dor

BB

(Nas) • Gold • Dor • Blue • Hol-B

Na~ice Nas Nas Nas Nas

BB

female

(16)

BB

(4)

73 58 17 43 113

(10) (7) (9)

Gold

(11)

Gold

(10)

15 13 13

48

(18)

Dor Dor

(38) (21)

Dor Blue

(37) (4)

16

39 60

Blue (13) Hol-B (34)

Blue Blue

(4) (18)

(5)

Hol-B (10) T (31)

Hol-B (9) Hol-B (64)

17

103 32

157

124

232

208

162

852

t e n y e a r s ago a n d k e p t s i n c e t h e n

for higher growth rate (unpublished).

It h a s

Big-Belly; t h i s r a c e of C h i n e s e c o m m o n c a r p w a s

i n t r o d u c e d t o I s r a e l f r o m T a i w a n i n 1970 ( L i n , p e r s o n a l communication). All the tested groups are listed in Table 1 according n u m b e r of p a r e n t s t h a t

in their reproduction by multiple spawns 1973) a n d n u m b e r of f i s h s t u d i e d

i n 1971 a n d i n 1 9 7 2 .

Methods Each group was spawned in a separate pond in the last w e e k of A p r i l .

59 93

H o l - B (12)

been kept as a closed line since 1965.

(Moav and Wohlfarth,

114

15 26 13

(e) Dot-70; t h i s I s r a e l i l i n e i s a p r o d u c t of a s e l e c t i o n

participated

7 9 9 9

Nas (17) Gold (7) Dor (15) Blue (7) Hol-B (10)

as a closed line.

t o t h e o r i g i n of t h e i r p a r e n t s ,

(6)

(29)

Total

(f)

BB

(17) (15) (16) (6) (14)

Holland-B ( H o l - B )

experiment

(6)

Nas Nas Nas Nas Nas

(4)

Blue • Hol-B

from the Netherlands

male

(18)

Blue-Grey (Blue) T

N o . of f i s h studied in 1971 1972

(5) (16)

Dor x Blue

Hol-B x T

Carp

and numbers

female BB xNas BB x Gold BB x Dor

in the Common

of f i s h s t u d i e d

1971

Big-Belly (BB)

Bones

N u r s i n g to m e a n w e i g h t s of 25 g ( W o h l -

f a r t h e t a l . , 1965) w a s a l s o c a r r i e d

out i n s e p a r a t e p o n d s .

The nursed fingerlings were brand-marked

T h e x - r a y p h o t o g r a p h s . C o u n t s of IM ( i n t e r m u s c u l a r ) a n d o t h e r b o n e s w e r e m a d e o n n e g a t i v e s of x - r a y p h o t o g r a p h s . In 1971 t h e c a m e r a u s e d w a s S o f t e x E - 3 , a n d i n 1972 it w a s S o f t e x E - 2 . T h e p h o t o g r a p h i c p l a t e s w e r e A g f a s t r u c t u r i x D7p F W . S m a l l s h e e t s of 20 x 10 c m w e r e c u t and inserted into black envelopes. During exposure the fish were laid on the envelopes and were marked by met a l n u m b e r s . In 1971 t h e n e g a t i v e s w e r e d e v e l o p e d w i t h an automatic Exomat instrument at the Hadassa Hospital i n J e r u s a l e m , a n d i n 1972 t h e y w e r e d e v e l o p e d w i t h s i milar equipment at the Rambam Hospital in Haifa. The developed negatives were fixed, washed and dried. For bone counting the negatives were magnified and illuminated by a Heliograph instrument. During exposure the fish were laid 20-30 cm from t h e s o u r c e of r a d i a t i o n ( 1 8 5 - 2 0 0 KV at 9 m A m p ) , f o r b e t w e e n 5 a n d 60 s e c o n d s d e p e n d i n g o n t h e s i z e of t h e f i s h . To s t o p t h e f i s h m o v i n g d u r i n g e x p o s u r e , t h e y w e r e c o l d shocked in a container filled with a mixture of ice and water. T h e t h i c k f r o n t p a r t of t h e c a r p b o d y r e q u i r e d l o n g e r e x p o s u r e t h a n t h e t h i n n e r t a i l . L a r g e f i s h ( o v e r 400 g) r e q u i r e d t h r e e e x p o s u r e d u r a t i o n s - l o n g e s t at t h e f r o n t ( u p to 60 s e c o n d s ) , s h o r t e r i n t h e m i d - b o d y , a n d s h o r t e s t f o r t h e t a i l r e g i o n . T h e IM b o n e s of t h e t h i c k f r o n t were the most difficult to count. Occasionally the end of t h e t a i l w a s s l i g h t l y o v e r - e x p o s e d , s o t h a t t h e p o s t e r i o r IM b o n e s w e r e a l s o n o t c o m p l e t e l y c l e a r .

(Moav et al.,

1960a,b), and stocked into communal (mixed) ponds servi n g p a r t of o u r e x p e r i m e n t s

for studying genetic differen-

Experimental

Results

c e s i n g r o w t h r a t e ( W o h l f a r t h a n d M o a v , 1972 ; M o a v a n d

T h e n u m b e r s of v e r t e b r a e ,

Wohlfarth,

t r a l IM b o n e s , d o r s a l f i n r a y s a n d i n d e x of b o n e d i s o r -

1973). When these experiments

mid November, for the present

samples study.

terminated

in

of f i s h w e r e x - r a y p h o t o g r a p h e d

ders were determined,

r i b s , d o r s a l IM b o n e s , v e n -

and from these counts, total hum-

b e r of IM b o n e s ( d o r s a l p l u s v e n t r a l ) ,

t o t a l n u m b e r of

Rom Moav et al. : Variability of Intermuscular Bones in the Common Carp

35

Table 2. Measurements on the studied characters (R=range ; M=mean; SE=Standard e r r o r ; OF=Coefficient of variation). A. Number

of vertebrae,

ribs and ventral

(ribs

plus ventral

intermuscular)

bones

Vertebrae

Ribs 1971

Group

Big-Belly ( B B ) BB BB BB

• Nas • Gold • Dor

Na~ice ( N a s ) Nas Nas Nas Na~

• • • •

Gold Dor Blue Hol-B

GoLd Gold • Dor Gold • Blue

Dot-70

(Dor) Dor x Blue

1972

M-30

SE

CV %

R

M-30

SE

CV %

R

2 2 0 1

4.1 4.1 4.0 4.4

0.4 0.2 0.0 0.2

3.1 1.8 0.0 1.8

6

3.6

0.1

2.3

2 1 1

5.5 5.0 4.9

0.2 0.0 0.1

1.9 0.6 1.1

5 2 3 3 3

5.3 5.3 5.5 4.4 5.2

0.1 0.1 0.2 0.1 0.1

1 1 2

5.1 5.5 5.1

0.1 0.1 0.2

1.0 1.4 1.6

2

5.1

3

4.4

0.2

2.3

2 3

Blue x Hol-B

Holland-B Hol-B

(Hol-B) • T

Mean (total)

B. Number

of dorsal

1972

R

B$ue-Grey (Blue)

SE

CV %

R

M-55

Se

CV %

4

0.0

0.1

3.8

11

3.6

0.2

3.8

2.0 1.4 2.3 1.9 1.8

4 4 4 4 6

1.2 2.5 2.4 1.0 2.3

0.1 0.1 0.3 0.1 0.1

3.6 3.1 3.8 3.3 3.7

11 9 8 8 12

5.6 7.8 5.9 4.7 5.3

0.3 0.3 0.6 0.2 0.3

3.8 3.0 3.8 3.4 3.5

0.1

1.3

4

1.8

0.2

4.2

8

5.7

0.3

3.3

4.7 4.6

0.I 0. I

1.6 1.6

2 4

1.5 1.5

0.1 0.1

2.8 3.0

7 13

5.1 4.8

0.3 0.3

2.9 4.1

2 3

4.7 5.5

0.1 0.1

0.1 1.7

4 6

1.1 2.1

0.1 0.1

2,6 3.5

8 11

5,5 6.7

0.3 0.2

3.4 3.4

5.3

0.1

1.3

3 2

5.5 5.2

0.1 0.1

1.6 1.6

4 2

2.0 1.9

0.1 0.2

3.5 3.3

12 13

4.4 4.7

0.2 0.2

3.8 3.9

3

4.9

0.1

2.2

8

4.9

0.0

2.5

6

1.6

0.1

4.3

16

5.3

0.1

4.0

and ventral

intermusoular

InterM

bones

bones

Ventral 1972

R

M-63

SE

CV

R

M-63

SE

CV

Big-Be I ly ( B B )

5 4 4 6

1.1 3.0 1.6 2.0

0.7 0.4 0.4 0.7

3.1 2.1 1.8 3,2

13

0.7

0.2

3.4

8 8 7

3.6 3.6 3.2

0.6 0.3 0.6

3.4 2.9 3.1

13 3 . 6 8 4.1 9 3.3 72.4 143.2

0.3 0.2 0.5 0.3 0.2

4 9 6

2.7 5.1 3.5

0.3 0.7 0.5

1.9 3.4 2.5

72.9

7

2.8

0.5

3.3

(Nas) • Gold • Dor • Blue • Hol-B

GoLd Gold • Dor Gold • Blue

Dot-70

(Dor) Dor • Blue

Blue-Grey ( B l u e ) Blue • Hol-B

Holland-B ( H o l - B ) Hol-B Mean

• T

(total)

InterM

bones

1971

Group

Nas Nas Nas Nas

1972

M-29

1971

Na~ice

bones

1

Dorsal

BB • Nas BB • Gold BB • Dot

Ventral

R

1972

M-26

SE

CV

R

M-26

SE

CV

5 5 4 5

0.7 1.6 1.2 1.3

0.7 0.5 0.4 0.5

7.4 5.8 4.7 5.5

12

3.6

0.2

6.8

3.4 2.6 3.4 2.5 2.9

7 8 7

1.1 1.7 1.8

0.5 0.4 0.5

6.4 6.6 6.5

11 7 6 7 11

4.4 5.2 3.5 3.7 3.0

0.3 0.2 0.5 0.3 0.2

7.7 5.2 7.1 5.8 6,5

0.2

2.5

9 7 4

1.1 1.3 1.6

0.6 0.5 0.4

8.6 6.2 5.2

8

4.0

0.3

5.6

82.8 202.8

0.3 0.3

3.0 4.0

13

0.5

0.8

11.9

8 12

3.7 3.3

0.3 0.3

5.4 7.7

93.0 113.9

0.2 0.2

2.8 2.7

7 10

4.4 4.5

0.3 0.2

6.3 6.4

7

3.5

0.5

3.1

11 12

3.3 3.7

0.2 0.5

2.8 4.1

r

1.8

0.4

6.5

9 13

2.4 2.8

0.2 0.4

6.6 7.7

10

3.2

0.2

_3.1

20

2.9

0.1

3.4

14

1.3

0.2

7.0

16

3.7

0.1

7.1

36

R o m M o a v et a l . : V a r i a b i l i t y o f I n t e r m u s c u l a r

C. N u m b e r of total i n t e r m u s c u l a r vertebrae

bones, dorsal fin rays and total intermuscular

Total InterM

bones

B o n e s in the C o m m o n C a r p

b o n e s d i v i d e d b y n u m b e r of

InterM/Vertebrae

1971

1972

1971

1972

Dorsal

fin rays 1972

Group

R

M-90

SE

CV

R

M-90

SE

CV

Mean

Mean

R

M-18

SE

CV

Big-Belly

7 5 4 10

0.9 3.7 1.8 2.3

1.0 0.5 0.5 1.0

2.9 1.6 1.6 3.2

16

3.4

0.3

3.3

2.66 2.75 2.70 2.68

2.78

6

0.6

0.1

5.7

Na~ioe Nas Nas Nas Nas

9 14 8

3.8 4.2 3.8

0.7 0.6 0.6

3.0 3.3 2.2

22 12 13 11 15

7.0 8.4 5.8 5.0 5.2

0.4 0.4 0.9 0.4 0.3

3.8 2.9 3.8 2.7 2.9

2.64 2.69 2.69

2.75 2.79 2.70 2.77 2.71

5 4 5 4 5

2.1 2.1 0.8 2.4 2.0

0.1 0.1 0.3 0.1 0.1

5.1 4.3 7.6 4.3 5.0

12 12 8

2.7 5.3 4.3

0.9 0.9 0.6

3.4 3.5 2.3

12

5.8

0.4

2.7

2.64 2.69 2.68

2.73

6

1.9

0.1

5.3

16

2.3

1.2

5.1

11 29

5.5 5.0

0.5 0.5

3.3 4.3

2.68

2.75 2.75

5

1.2

0.1

4.2

12 13

6.4 7.4

0.3 0.3

2.7 2.6

(BB) BB xNas BB • BB xDor (Nas) • • • •

Gold GoldxDer Gold •

Dor-70

(Dor) Dor •

Blue-Grey

(Blue) Blue xHol-B

Holland-B

(Hol-B) Hol-B NT

Mean (total)

2.78 2.75

12

4.2

0.8

3.4

14 14

4.7 5.1

0.3 0.7

2.9 3.9

2.67

2.67 2.71

4

2.7

0.2

5.6

20

3.5

0.3

3.4

29

5.6

0.1

3.5

2.68

2.74

9

1.8

0.0

5.8

D . B o n e d i s o r d e r s a n d a x 2 t e s t f o r i n d e p e n d e n c e of l i g h t a n d s e v e r e d i s o r d e r s ( 1 0 0 P % = p e r c e n t a g e of f i s h s h o w i n g b o n e d i s o r d e r s ; t h e f o u r c l a s s e s of d i s o r d e r s w e r e d e f i n e d i n t h e t e x t )

Proportion

and Index of bone

disorders

1971 Group

100P ~

Big-Belly (BB) BB BB BB

Na~ioe Nas Nas Nas Nas

xNas xGold • (Nas) • • • Blue x Hol-B

Gold Gold • Dor Gold y Blue

Dot-Y0

(Dor) Dor x Blue

1972

M

SE

57 78 78 67

1.6 1.6 2.1 0.7

0.9 0.5 0.9 0.2

100 96 100

5.2 2.1 2.9

87 92 62 88

0

1-4

5

6-9

22

0.8

0.2

89

16

3

5

11.9~

0.5 0.4 0.5

63 41 65 61 86

2.0 1.1 2.1 1.4 2.2

0.3 0.3 0.5 0.3 0.2

27 34 6 17 16

33 18 8 20 88

3 3 0 5 4

10 3 3 1 5

2.1 0.5 2.0 2.9 4.8~

1.9 2.3 0.9

0.5 0.4 0.3

60

2.3

0.4

19

16

5

8

6.9~

2.9

0.7

33 57

0.7 2.1

0.3 0.4

26 26

11 21

1 3

1 9

0.4 3.5

46 40

1.7 0.9

0.3 0.2

32 56

16 31

2 2

9 4

8.6 ~ 2.3

Holland B ( H o I - B ) Mean (total)

84

1.5

0.3

89 63

2.0 2.3

0.1 0.5

11 12

85 12

2 2

5 6

85

2.2

0.2

57

1.6

0.1

371

375

35

69

S i g n i f i c a n t at t h e 5 ~ l e v e l ~

(1972)

SE

Blue • Hol-B

100P ~

of d i s o r d e r s

M

Blue-Grey ( B l u e )

HoI-B •

N o . of f i s h at f o u r c l a s s e s

Significant at the 1 ~ level

X~

1.2 3.4 9,5 ~

R o m M o a v e t a l . : V a r i a b i l i t y of I n t e r m u s c u l a r

Bones in the Common Carp

37

t h e m e a n of t h e t w o p a r e n t s . 30 31

measure

32 33

nance (Falconer,

128

1960). Ten F t crossbreds

ted simultaneously

I

3ol 32 I

I

I

I

I

i

I

I

60 50 40 30 28 10 0 10 20 30 50 40 30 20 10 0 10 ZO 30 40 a Vertebrae b Ribs

z7 ~29

I

7O I

84 86 88 90 92

23 Z5

,I

96

35 I I

J i l l

were crossbreds

F o r m o s t of t h e s t u d i e d c h a r a c t e r s the inter-parental

I I

e Total IN bones

___J

F

associated

ratio was large. Variation between individuals within ~roups and between Table 4 shows,

the means

(over

I

i,

I

I

I

, I

I

l

p r e s e n t c a s e it e s t i m a t e d genetic variance

F

I

I

I

I

I

correlation

t,

I

80 70 60 50 40 30 20 10 0 10 20 30 40 30 ZO 10 0 10 20 f Index of bones disorders g Oorsol fin roys F i g . 1. T h e f r e q u e n c y d i s t r i b u t i o n s of s e v e r a l b o n e c h a r a c t e r s in the two groups Big,Bel~y (BB) and Na~J~ee • C-old (BB) (n = 114) is presented by the left hand columns and E a ~ o e x Go~d (n = 58) by the right hand columns

components).

to heritability,

and in the

t h e p r o p o r t i o n of i n t e r g r o u p

in the total variance.

Table 4 also

between the years ( o r SD) of

though small in absolute terms

l a t i o n to t h e w i t h i n v a r i a n c e s , from zero.

However,

necessarily

mean usefulness

and in re-

all varied significantly

statistical

s i g n i f i c a n c e d o e s not

to t h e b r e e d e r ,

i.e.,

al-

t h o u g h t h e b e t w e e n g r o u p s SD of t o t a l IM b o n e s i s h i g h ly significant, useless

ventral bones (ribs plus ventral IM bones), and the

co-

component divided by

1971 a n d 1 9 7 2 . The b e t w e e n g r o u p v a r i a n c e s all the traits,

the

the between groups

shows a reasonably good agreement

!1' I .~2 I

for all the studied

all the tested groups),

Standard deviations and the intra-class

This coefficient is similar

18

so

with the dominance

t h e s u m of t h e w i t h i n p l u s b e t w e e n v a r i a n c e

91

I

9 10

and crossbreds

r a n g e (2 a ) w a s r e l a t i v e l y s m a l l ,

that the relative error

efficients (the between variance 15 16 17

were compu-

population (Table 3).

within groups Standard deviations, 30 20 10 0 10 20

lines. The

d o m i n a n c e r a t i o s of t h e v a r i o u s c h a r a c t e r s

characters,

i

of the Chinese

among the five European

the ~roups means.

30 20 10 10 20 30 30 20 10 0 10 20 c Dorsal M bones d Ventral IM bones

crossbreds

T h r e e of

and a European line, and the remaining seven

ted for each crossbred 58 :60 152

as a

were tes-

with their two parents.

these ten were inter-racial

B's I

The ratio d/a serves

of t h e r e l a t i v e d e g r e e a n d d i r e c t i o n of d o m i -

it is negligibly small (1.3)

and practically

in a breeding scheme aimed at reducing the num-

b e r of IM b o n e s .

ratio: total n u m b e r of I M bones to n u m b e r of vertebrae, w e r e computed. The m e a n s ( M ) , ranges (B) , Standard

Correlation

errors (SE) and Coefficients of variation (CV-Standard

between crossbreds

deviation divided by the m e a n ) of the above characters

ces

are presented in Tables 2A, 2B, 2C, and 2D. F o r the in-

families, etc. ) may serve for estimating genetic variance

dex of bone disorders the proportion of fish having any

p r o v i d e d t h a t t h e c o n t r i b u t i o n of t h e i ' c o m m o n e n v i r o n -

kind of disorder w a s c o m p u t e d (Table 2D, the •

ment" component to the intra-class

of this table will be discussed later). The intra-group

the relative similaritybetween

frequency distributions of the 1972 samples of the two

O u r d a t a c o n t a i n t w o l i n e s of e v i d e n c e tO t h i s e f f e c t :

between

b e t w e e n t h e r e s u l t s of i 9 7 1 a n d 1972 ~ a n d means

and their parents

e x treme groups B4g-BeZZy and Na4~1;ee x ~oZd are pre-

(a) the correlation

sented in Fig. I.

g r o u p s in t h e t w o y e a r s

Dominance relationships. ured by d/a,

The dominance ratio was meas-

when d is the difference between the mean

of a n F 1 c r o s s b r e d

and the mid-point

(unweighed mean)

of i t s two p a r e n t s a n d a i s h a l f t h e d i f f e r e n c e b e t w e e n

means.

Differen-

of g e n e t i c g r o u p s ( l i n e s ,

correlation

group mates)is

between performance 1971 a n d 1 9 7 2 ,

strains,

(i.e.,

negligible.

of t h e s a m e and (b) the

correlation

between crossbreds

both cases,

only genetic factors contribute to the cova-

r i a t i o n . Two of t h e f o u r p r i m a r y

and their parents. characters

In

measured

in i97i and i972 showed a high between~years t i o n . T h e s e w e r e : ( i ) n u m b e r of v e r t e b r a e ,

to

corre!awith acor-

38

R o m M o a v et a l . : V a r i a b i l i t y of I n t e r m u s c u l a r B o n e s in t h e C o m m o n C a r p

r e l a t i o n c o e f f i c i e n t of O. 8 ; a n d ( i i ) d o r s a l IM b o n e s w i t h

ent. W ithin the European race, the inter-group ( genet-

an e x t r e m e l y

ic) range was less than one vertebrae

high correlation

m a i n i n g two c h a r a c t e r s bone disorders

of 0 . 9 8 .

For the re-

- v e n t r a l IM b o n e s a n d i n d e x of

- t h e c o r r e l a t i o n s w e r e c l o s e t o n i l . The

t h e two y e a r s a r e c o n s i d e r e d ) .

Big-Belly

y e a r s c o r r e l a t i o n o f t o t a l IM ( d o r s a l p l u s v e n t r a l ) b o n e s

nance r a t i o , o v e r the two y e a r s ,

to 0 . 7 4 .

zero (Table 3).

The c o r r e l a t i o n c o e f f i c i e n t s of c r o s s b r e d s

with their

r a n g i n g b e t w e e n O. 15 f o r t h e i n d e x of b o n e d i s o r d e r s to over 0.5 for vertebrae,

r i b s a n d d o r s a l IM b o n e s ( r i g h t -

correlations (between years, andbetween crossbreds their parents)

and

l e a d s to t h e c o n c l u s i o n t h a t g e n e t i c d i f f e -

Na~iee

( 3 8 ) , and one

h a d t h e l o w e s t n u m b e r ( 3 0 ) . The a v e r a g e d o m i of t h i s c h a r a c t e r w a s

N u m b e r of r i b s . R i b s w e r e c o u n t e d o n l y on o n e s i d e of the body and the counted n u m b e r was multiplied by two. H e n c e t h e e x c l u s i v e l y e v e n n u m b e r s ( F i g . l b ) . The Chinese

h a n d c o l u m n , T a b l e 4 ) . T h u s , t h e e v i d e n c e o f t h e two

One fish of the

group had the h i g h e s t n u m b e r of v e r t e b r a e

z e r o c o r r e l a t i o n of v e n t r a l IM b o n e s r e d u c e d t h e i n t e r -

p a r e n t s m e a n s f o r t h e 1972 r e s u l t s w e r e all p o s i t i v e ,

(when means over

Bi.g-BeZZy h a d

and the i n t r a - E u r o p e a n

two r i b s l e s s t h a n t h e E u r o p e a n , range was rather small.

N u m b e r of I n t e r m u s c u l a r b o n e s . D o r s a l a n d v e n t r a l IM

r e n c e s c o n s t i t u t e t h e m a j o r s o u r c e of i n t e r - g r o u p v a r i a -

b o n e s a p p e a r to b e h a v e l i k e two d i f f e r e n t c h a r a c t e r s

t i o n i n n u m b e r of v e r t e b r a e ,

( T a b l e s 2B a n d 2C, a n d F i g . l c a n d l a ) . The c o e f f i c i e n t

n u m b e r of d o r s a l IM b o n e s ,

a n d t o t a l IM b o n e s .

of v a r i a t i o n ( C V ) of n u m b e r of v e n t r a l IM b o n e s w a s m o r e

Correlations between characters.

t h a n t w i c e t h a t of d o r s a l IM b o n e s ( 7 . 1 % v e r s u s

Two k i n d s of c o r r e l a -

tions between characters were computed, the correlation b e t w e e n individuals w i t h i n g r o u p s and the c o r r e l a t i o n b e tween group means.

T h e s e c o r r e l a t i o n s , b a s e d on t h e

1972 r e s u l t s o n l y , a n d e x c l u d i n g t h e C h i n e s e

Big-Br

3.4%,

T a b l e 2 B ) , but i t s r e l a t i v e g e n e t i c ( b e t w e e n - g r o u p s ) v a r i ance was considerably smaller.

A partial explanation for

t h i s differenCe m a y be the h i g h e r e r r o r in counting v e n t r a l IM b o n e s . The s i g n i f i c a n t d i f f e r e n c e of a l m o s t 2 . 5

g r o u p , a r e p r e s e n t e d i n T a b l e 5 . The w i t h i n - g r o u p c o r r e -

v e n t r a l IM b o n e s b e t w e e n t h e m e a n s of 1971 a n d 1972

l a t i o n s ( m e a n s o v e r all t h e g r o u p s ) a r e l o c a t e d a b o v e ,

( 2 7 . 3 -+ 0 . 1 i n 1971 a n d 2 9 . 1 +- 0 . 1 in 1972) m a y b e

par-

and the b e t w e e n - g r o u p s c o r r e l a t i o n s below the m a i n di-

t i a l l y d u e t o t h e s a m e r e a s o n . The d o r s a l IM b o n e s , o n

agonal.

t h e o t h e r h a n d , s h o w e d a l m o s t i d e n t i c a l m e a n s in t h e

The s o u r c e s of w i t h i n - , a n d b e t w e e n - g r o u p s c o v a r i a t i o n a r e i d e n t i c a l t o t h o s e of t h e w i t h i n - , a n d b e t w e e n groups variances. Thus, the between-group correlation

two y e a r s ( 6 6 . 2 -+ 0 . 2 in 1971 a n d 6 5 . 9 + 0 . 1 in 1972, Table 2C). The c o r r e l a t i o n b e t w e e n d o r s a l IM b o n e s in t h e two

a r e l a r g e l y d u e to g e n e t i c c o v a r i a t i o n , w h i l e t h e w i t h i n -

y e a r s w a s 0498, but p r a c t i c a l l y z e r o ( - 0 . 0 1 ) ,

groups correlations

t r a l IM b o n e s . The l a t t e r low v a l u e m a y b e a n o t h e r r e -

a r e s t r o n g l y a f f e c t e d by e n v i r o n -

for ven-

mental factors. Table 5 shows that for most character

f l e c t i o n of t h e g r e a t e r d i f f i c u l t y in c o u n t i n g v e n t r a l IM

combinations the between-groups correlation was higher

b o n e s , but it m a y a l s o b e d u e to h i g h e r s e n s i t i v i t y of

than the within:group correlation.

t h e s e b o n e s to e n v i r o n m e n t a l v a r i a t i o n .

This fits the c o m m o n

situation where environmental sources tendto reduce, r a t h e r t h a n to e n h a n c e , i n t e r - c h a r a c t e r

correlations.

T a b l e 5 a l s o s h o w s t h a t p r a c t i c a l l y all t h e h i g h c o r r e l a t i o n v a l u e s a r e r e s t r i c t e d to c h a r a c t e r s

t h a t a r e , by d e -

f i n i t i o n , p a r t - w h o l e p a i r s , 1 . e ; , t o t a l IM b o n e s ( w h o l e ) a n d v e n t r a l IM b o n e s ( p a r t ) ,

a s w e l l a s to c h a r a c t e r s

that a r e s t r o n g l y a s s o c i a t e d with n u m b e r of v e r t e b r a e , i.e.,

vertebrae

and r i b s a r e h i g h l y c o r r e l a t e d

and so a r e v e r t e b r a e

(0.7)

a n d d o r s a l IM b o n e s ( 0 . 8 ) .

Con-

s e q u e n t l y , r i b s a r e a l s o c o r r e l a t e d w i t h d o r s a l IM b o n e s

T o t a l n u m b e r of v e n t r a l b o n e s . R i b s a n d v e n t r a l IM b o n e s w e r e d e f i n e d a s v e n t r a l b o n e s . S i n c e v e n t r a l IM b o n e s a r e l o c a t e d o n l y p o s t e r i o r to t h e r i b s , " c o m p e t i t i o n " b e t w e e n t h e two t y p e s of b o n e s i n t h e b o r d e r r e g i o n s h o u l d c a u s e n e g a t i v e c o r r e l a t i o n b e t w e e n t h e two t y p e s of b o n e s . However, our results show zero correlation between the two ( T a b l e 5) ; t h e r e f o r e , should be rejected,

t h e h y p o t h e s i s of " c o m p e t i t i o n "

and we m u s t c o n c l u d e that the b o r -

d e r l i n e b e t w e e n t h e two i s f i r m l y d e t e r m i n e d . The m e a n n u m b e r of v e n t r a l b o n e s w a s 6 0 . 3 • O. 1

(0.6).

( T a b l e 2A) c o m p a r e d w i t h 6 5 . 9 • 0 . 1 : d o r s a l IM b o n e s . N u m b e r of v e r t e b r a e .

The C h i n e s e

B'Lg-BeT.7.y h a d

signi-

This difference shows that three vertebral segments

ficantly f e w e r v e r t e b r a e than the E u r o p e a n c a r p and the

c o n t a i n i n g d o r s a l IM b o n e s h a v e n e i t h e r ~r i b s n o r v e n -

inter-race

t r a l tM b o n e s ,

crossbreds

w e r e s i m i l a r to t h e i r C h i n e S e p a r -

0.1 0.3

0.1

0.4-0.9

0.2-1.5

0.5-0.2

Mean : BB • Eur

N a s • Gold

Nas • Dor

0.4

0.2

0.4

0.4-0.2

B l u e • Hol B

European mean

Overall mean

0.7

0.0

D o r • Blue

1.9 0.2

0.4

0.1

0.00.2

1.0 0.4

-27.0

-2.3

0.1

0.3

-2.2

0.3

Nas • HoI-B

Gold • Dor

0.3

a

2.4

1.4

1.5

1.9

-2.7

8.9

3.4

d/a

1972

Ribs

1.6 0.1

1.3

d/a

1972

N a s • Blue

1.0

-1.3

0.5

BB • Dor

a

BB • Gold

-1.0

d/a

0.7

a

1971

BB • Nas

Group

Vertebrae

0.2

0.5

a

1.0

2.4

0.0

2.2

0.8

3.0 0 . 7

-2.0

-0.6

-4.9

-0.6

3.2

d/a

1972

bones

0.6

0.3

0.1

0.4

0.5

0.9

0.8

0.8

1.2

a

0.8

3.1

33.4

0.3

0.1

0.1

0.2

0.2

0.4 0.4

1.0

a

0.1

0.0

0.0

-0.5

0.5

d/a

1971

0.3

5.1

-1.4

-1.4

-2.8

1.8

0.2

3.7

0.211.1

0.3

-0.4

-1.5

5.0

d/a

0.5

1.0

-0.1

1.1

O. 4 - 2 . 2

1.0

0.0

0.2

0.2

3.5 0 . 4

a

0.3

3.7

6.9

1.8

3.7

d/a

2 . 2 ~0.0

0.2

0.1

0.2

0.2

a

1971

1972

d=dominance

Ventral

means;

d/a

1972

the parental

Dorsal

between

0.5

1.2

0.3

0.8

1.8 0.6

0.7

1.0

0.0

0.9

d/a

0.213.31

0.7

0.5

1.0

0.7

0.9

1.5

a

1971

Total

Intermuscular

3"able 3. D o m i n a n c e r a t i o s o f t h e s t u d i e d c h a r a c t e r s (a=half the range the mean of the crossbred and the mid-parental value)

0.3

0.5

0.1

0.1

0.4

0.5

0.1

a

0.5

1.2

1.6

0.9

0.7

0.2

1.8

a

1.0

-1.0

-0.8

-0.2

-1.0

-0.8

-1.1

-2.3

2.0

-1.0

d/a

1971

0.3

0.1

0.5

0.0

0.1

0.6

0.2

a

Index of bone disorders

difference

0 . 1 ! 1.1

-0.2

7.8

-3.3

1.8

-1.8

0.5

d/a

1972

Dorsal fin rays

deviation=the

-0.3

-6.4

1.9

16.3

-~.5

1.2

-6.3

d/a

1972

between

O~ raO

Q m

o

Q o

b~

o

Z

oo