الفهرس 
ContentsOnly 14 pages are availabe for public view
 |  | from | 167 |  |  |
| | | from | 167 | | |
Abstract
This work was carried out at the animal production dept. experimental farm faculty of agriculture university of Mansoura. The experiment started with 51 male calves at average age of 7 months and ended by a number of 38 calves at the age of 18 months when they were slaughtered. The objective of this study was to evaluate body weight at different ages as well as body measurement and feed efficiency. The carcass traits which were included slaughter weight, carcass weight and percentage, organ’s and offals weights and percentages, dressing percentage, carcass composition, boneless meat and percentage, chemical analysis and histological test were estimated. Effect of farms and year of birth on these traits were studied. Data of body weight. body measurements, feed efficiency and carcass traits were then corrected for these effects. The phenotypic correlations between body weight and body measurements were calculated. The results obtained from this study are summarized in the following : I • Live body weights : l, The overall mean of body weight at birth was 34.22 ± 0.88 kg. It was found that the differences between farm in mean birth weight were significant. Meanwhile. The effect of year of birth was non-significant. 2. The means of daily gains at the age of 8, 12 and 18 months were 0.86 ± 0.07, 0.88 ± 0.06 and 0.44 ± o.o8 kg., respectively. It was also found that the average daily gain during the periods from birth to 8 months, from 8 to 12 months. from 12 to 18 months, from 8 to 18 months and from birth to 18 months were 0.56 ± 0.02, 0.52 ± 0.02, o.68 ± O.O3, 0,61 ± 0,02 and 0.53 .± 0.01 kg., respectively.