W. Wittmann et al., FATTENING AND CARCASS PERFORMANCE TRAITS OF GERMAN LANDRACE CASTRATESGENETICALLY DIFFERENTIATED BY THE MHS-GENE-TEST, Zuchtungskunde, 65(3), 1993, pp. 197-205
With the aid of the MHS-gene-test the genotypes of the disposition for
the development of the malignant hyperthermie-syndrome was determined
in 229 male DL-castrates of the progeny testing on the test stations
Grub and Schwarzenau. Between the three possible MHS-genotypes NN (pur
e stress-resistant), NP (mixed stress-resistant) and PP (pure stress-s
usceptible) the former two showed lesser differences of the performanc
e traits than to the latter. Concerning the NN-animals the following d
ifferences could be verified in comparison to the NP- and PP-castrates
: 1. a lower daily gain (26-34 gr) 2. higher fat-thickness measurement
s (0.1-0.5 cm) with a increased fat surface (0.9-2.5 cm2) 3. a reducti
on in thickness (0.2-0.6 cm) and surface (1.5-5.6 cm2) of the loin 4.
a lower lean meat (0.8-2.7%) and ham yield (0.7-1.0%) 5. a lower quali
ty of the belly (0.3-1.4 points) 6. better meat quality traits (pH-val
ues 0.08-0.79 and meat brightness 2.5-12.3) According to the improveme
nt of the meat quality not anyone of the NN-animals showed the PSE-def
iciency, but 46.2% of the PP-genotypes developed this meat quality. 90
animals could be examined of stress-disposition by the CK-test. Only
all of the PP-genotypes showed levels in the stress-susceptible range
of greater-than-or-equal-to 3.0. The selection on homozygous stress-re
sistant animals in a population leads to a conversion of the type of a
nimals, however, there must not be expected a severe reduction in the
performance traits of economical interest. The variation between the M
HS-genotypes can be used to select NN-animals with high performance tr
aits in every respect.