Callipyge:
big butt
Genetic
mutation explains ‘beautiful
buttocks’ in sheep
(http://www.genomenewsnetwork.org/articles/10_02/beautiful_buttocks.shtml)
See:
N. E. Cockett, S. P. Jackson, T. L. Shay, F. Farnir, S. Berghmans,
G. D. Snowder, D. M. Nielsen, and M. Georges.
Polar overdominance
at the Ovine callipyge locus. Science 273 (5272):236-238,
1996
Growth and feed intake (from
S. P. Jackson, R. D. Green, and M. F. Miller. Phenotypic characterization
of rambouillet sheep expressing the Callipyge gene .1. Inheritance
of the condition and production characteristics. J.Anim.Sci. 75
(1):14-18, 1997)
|
Trait |
Callipyge |
Normal |
|
Average daily gain, g/d |
|
|
|
Rams (n = 42) |
360 |
350 |
|
Wethers (n= 54) |
260 |
290 |
|
Ewes (n = 24) |
290 |
310 |
|
Daily feed intake, kg/d |
|
|
|
Rams (n = 42) |
1.75 |
1.90 |
|
Wethers (n= 54) |
1.48 |
1.68 |
|
Ewes (n = 24) |
1.67 |
2.11 |
|
Gain per pound of feed |
|
|
|
Rams (n = 42) |
0.203 |
0.185 |
|
Wethers (n= 54) |
0.173 |
0.165 |
|
Ewes (n = 24) |
0.175 |
0.148 |
Muscle
growth and meat tenderness. (from M. Koohmaraie, S. D. Shackelford,
T. L. Wheeler, S. M. Lonergan, and M. E. Doumit. A muscle hypertrophy
condition in lamb (callipyge): Characterization of effects on
muscle growth and meat quality traits. J.Anim.Sci. 73
(12):3596-3607, 1995)
|
Trait |
Callipyge |
Normal |
|
Slaughter weight, kg |
54.2 |
54.0 |
|
Hot carcass weight, kg |
29.1 |
27.9 |
|
Dressing percentage |
53.6 |
51.3 |
|
Loin eye area, cm2 |
19.8 |
14.8 |
|
Gluteus muscle group weight, g |
759 |
580 |
|
Longissimus muscle weight, g |
1891 |
1432 |
|
Warner-Bratzler shear forice, kg at 7 days post mortem |
10.1 |
4.7 |
|
