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Extensive fattening involved F1 generation heifers coming from intentional breeding of the dams of Black Pied (N) and Bohemian Pied (C) cattle having below-average milk performance with three sires of the Hereford (HRF), Limousin (Li) and Bohemian Pied (C) breeds. Young heifers were raised in a large calf-house, fattening took place in a cowshed with loose housing on slats. Feed ration was genotype constant. Fattening performance and figures of carcass and technological analyses were assessed. Some traits of meat quality were evaluated in the eye-muscle sample.

As for fattening performance, there was a difference in pre-slaughter weight only (Tab. 1). The heifers were slaughtered at old age - HRF heifers reached 669.80 days, Li heifers 648.00 days and C heifers 638.40 days. The fattening of HRF heifers lasted 503.90 days, in the Li and C groups it was shorter by 9.30 and 9.60 days, respectively. The daughters of HRF bulls reached slaughter weight of 416.70 kg, which is by 6.17 % (25.70 kg) more than in the Li group and by 8.50 % (35.40 kg) more than in the C group. The weight of dressed carcass was highest in Li heifers (233.30 kg) while in the HRF and C heifers it was lower by 10.40 kg arid 24.60 kg, resp. According to these weights, dressing percentage was 55.26 % in the Li group, and 53.52 % and 54.80 % in the HRF and C groups, respectively.

Body conformation (Tab. II) showed significant differences only in the chest girth behind the bladebone. The bulls of HRF cattle considerably influenced the body conformation of their daughters, their daughters had the smallest body framework with the mean height in hips 127.30 cm (the C and Li heifers had 131.30 and 128.20 cm, resp.), but the deepest chest (63.40 cm) and the largest chest girth behind the bladebone (187.10 cm) with the respective differences of 1.80 cm and 0.80 cm, and 10.30 cm and 11.80 cm against the Li and C breeds in the latter case.

The percentage (and weight) of skin (Tab. III) was highest in the HRF heifers, 8.95 % (i.e. 37.30 kg); the values in the Li group were 7.81 % (30.50 kg) and 8.16 % (31.10 kg) in the C group. The total production of fats 15.55 kg and 3.73 % was higher in the HRF heifers than in the Li heifers with 2.54 kg and 0.40 % and in the C heifers with 4.31 kg and 1.69 %. The tendency of absolute values and percentages of slaughter weight was identical in all processed fats (except visceral fat). There were significant differences in the deposition of subcutaneous fat: fat thickness of 4.93 mm was determined in the HRF heifers, 3.13 mm in the Li heifers and 3.02 nun in the C heifers.

There were no significant differences in the average weight of half-carcasses between the groups (Tab. IV). The weight of the half-carcass was 107.19 kg, 104.11 kg and 101.20 kg in the HRF, Li and C heifers, respectively. Between-the-group differences were significant in meat of quality I and II and in separable fat. The highest percentage of quality I meat was found out in the Li group - 43.04 % (44.85 kg); in the C heifers it was by 1.84 % less and in the HRF heifers by 3 % less. As for quality II meat, its percentage was highest in the HRF group - 41.00 % (44.01 kg), in comparison with the Li and C groups with the values by 3.40 % and 2.04 % less, respectively. The HRF group had the highest percentage of total meat production - 81.04 % (86.94 kg), the production of the Li and C groups was lower by 0.42 % and 0,87 %, resp. Fattening extensity and lower slaughter weight resulted in a low deposition of fat (highest in HRF - 1.27 %) and bone proportion (highest in C - 19.16 %). The largest eye-muscle area (65,14 cm2) was determined in the Li heifers (Tab. V), while these values made 59.18 cm2 in the HRF heifers and 58.67 cm2 in the C heifers; the differences were insignificant. The pH value from 5.25 to 5.59 indicates a good quality of meat (significant differences), while the very good quality is documented by meat color in the HRF and Li breeds (28.94 and 28.57 nm). The good-quality meat of the C heifers had darker color (22.90 nm). The differences were statistically significant, similarly like in the content of dry matter and fat in the eye-muscle sample.