Génétique animale,

(1)

Comparison ^of the crossbred progeny ^of belgian

landrace

and pietrain ^boars

P. SELLIER

.Station de

Génétique ^animale,

^{I. N. R.}^A.,^{C. N. R.}

^Z.,

78350

Jouy

^en

Josas

Both

Belgian

^Land^y^aceand Pietvain boars were

randomly

^used

by

^A.I.^onFren<:h Landrace

x

Large

^White^sowsof commercial farms. Females and castrates from resultant litters were sent to an

experimental

station where

they

^werefed ad libitum

(test starting

at 30

kg)

^and

slaughtered

at about

100 kg.

^Data^were^recorded^on

1 6 4 pigs

^from²^rlitters sired

by

^rz

Belgian

^La⁷zdvace boars

(XLB)

^and^on152

pigs

^from²²litters sired

by

5 Pietrain boars

(XPP). Daily

^feed

consumption

was io p. ¹⁰⁰

(P

^<

o.oor) higher

^{in XLB}

pigs

which excel XI’P

pigs

in average

daily gain

^on test ; ^however^aninteraction sex x

breeding

group

(P

^<

0 . 01 )

^wasevidenced for the latter trait : the

advantage

^{of XLB}^was

larger

in barrows

(I I I g)

^{than in}

gilts ( 57 g).

^The^sameinteraction tends to exist for food conversion

(I’

^<

o.1 5 ) 3 .r6

^ws3.37 in barrows, 3.z3 ^vs3.27 in

gilts

^{for XLB}

and XPP groups,

respectively.

^No

significant

difference between

breeding

groups ^wasfound in

dressing

^out

percentage,

average backfat

thickness, weight

of backfat and

weight

^of

ham;

however XPP

pigs

^had^a^shorter^carcass

(I’

^<

0 . 001 ),

^a

higher weight

^{of loin}

(P

^<

0 . 001 )

and a lower

weight

of leaf fat

(P

^<

0 . 05 ).

^A

slight superiority

^{of XLB}

pigs

^as

compared

to XPP

pigs

^wasfound with

respect

^{to meat}

quality,

assessed 24 hours

post

^movtem.The 3-way

cross with

Belgian

Landrace boars showed a mean

advantage

of about rr.5 F per

pig

^on^the

3

-way ^crosswith Pietvain boars in overall economic merit but due to the interaction

sex x

breeding

group for

fattening

cost, the difference was

larger

ⁱⁿ^barrows

( 17 . 5 F)

^than

in

gilts ( 5-5 1!).

Study ^of ^the malignant hyperthermia syndrome ⁱⁿ pietrain ^{breed :} first results

G. MONIN L. OLLIVIER* P. SFLLIFR*

Station de Recherches sur la Viande, I. N. R. A., .,

Theix, Saint Genès

Champanelle,

⁶³¹¹⁰^Beaumont

* Station de

Génétique

^animale,^{1. N.}^R.^A.,C. IV. R. Z., 78350

Jouy

^en

Josas

A

sample

^of

13 8

^Piet^y^ainfemales and castrates was

subjected

^to^a

5 -minute

anaesthesia with

halothane,

^at^anage of about 80

days. Thirty-nine

^of^them,^denoted

(+),

exhibited the ma-

lignant hyperthermia syndrome

^after^anaverage ²

1/2

minute anaesthesia while the others

Génétique animale,

Comparison of the crossbred progeny of belgian

and pietrain boars

Génétique animale,

Z.,

Jouy

Josas

Belgian

randomly

by

Large

experimental

they

(test starting

kg)

slaughtered

100 kg.

1 6 4 pigs

by

Belgian

(XLB)

pigs

by

(XPP). Daily

consumption

(P

o.oor) higher

pigs

pigs

daily gain

breeding

(P

0 . 01 )

advantage

larger

(I I I g)

gilts ( 57 g).

(I’

o.1 5 ) 3 .r6

gilts

respectively.

significant

breeding

dressing

percentage,

thickness, weight

weight

ham;

pigs

(I’

0 . 001 ),

higher weight

(P

0 . 001 )

weight

(P

0 . 05 ).

slight superiority

pigs

compared

pigs

respect

quality,

post

Belgian

advantage

pig

breeding

fattening

larger

( 17 . 5 F)

gilts ( 5-5 1!).

Study of the malignant hyperthermia syndrome in pietrain breed : first results

Champanelle,

Génétique

Jouy

Josas

sample

13 8

subjected

Comparison ^of the crossbred progeny ^of belgian

and pietrain ^boars

Génétique ^animale,

^Z.,

Study ^of ^the malignant hyperthermia syndrome ⁱⁿ pietrain ^{breed :} first results