الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
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SUMMARY
This study was carried out at El-Serw Experimental
Station belonging to the Animal Production Research Institute,
Agricultural Research Center, Ministry of Agriculture,
to evaluate the carcass of Rahmani lambs under
four feeding regimes. Lambs of the l~, 2nd and 4th feeding
regimes were fattened for 8 weeks when they reached
16, 24 and )2 wee~s of age, respectively, while those of
the 3~ feeding regime were fattened for only 4 weeks
started at 32 weeks of age. Slaughter was performed at
the end of the fattening periods. All experimental lambs
were fed on a growth ration from weaning at 8 weeks of age
up to the start of fattening; Experimental lambs were assigned
at random from those born as singles during June and
July, 1983. The least squares procedures were followed tor
the statistical analysis. Results obtained could be summarized
as follows:
Body Weight and Weight Gain:
1. Body weight ot all the experimental lambs averaged 12.94
~ 0.36 kg .~ weaning at 8 weeks of age and 19.88 ± 0.53 kg
at 16 weeks ot age. Daily gain trom 8 to 16 weeks at age
for all experimental lambs averaged 0.124 -+ 0.005 kg.
2. Average body weight was 29.78 kg tor lambs ot the 1.!1
feeding regime at 24 week. ot age, 39.12 kg tor those of the
2nd feeding at )2 weeks ot age, 47.67 kg for those of the
3rd feeding regime at 36 weeks ot age and 54.17 kg tor those
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of the 4!h feeding regime at 40 weeks of age. Weaning weight
was always a highly significant (P~ 0.01)source of
variation in 24-, 32-, 36-, and 40-week weight. It showed
positive dependent relationship with these weights.
3. The mean of average daily gain was 0.165 kg in lambs of
the first feeding regime (from 16 to 24 weeks), 0.203 kg
in lambs of the 2~ feeding regime (from 24 to 32 weeks),
0.235 kg in lambs of the 3!£ feeding regime (from 32 to 36
weeks) and 0.229 kg in lambs of the 4ih feeding regime
(from 32 to 40 weeks of age).
4. Differences between the fattened lambs and their controls
in body weight at 24 weeks of age were not significant. Differences
in gain from 16 to 24 and from 24 to 32 weeks of
age between the same experimental groups followed the same
pattern.
Feed Conversion:
5.. Feed conversion values ’tor early fattened lambs (from 16
to 24 weeks of age) were 2.869 kg S.E. aa4·O.565 D.P.!kg”gain.
The corresponding values were 3.096 kg S.E. and 0.6OB kg D.P./
kg gain for intermediate fattened lambs (from 24 to 32 weeks
of age), 3.•042 kg S.E. and 0.591 kg D.P./ kg gain for short
late fattened lambs (from )2 to 36 weeks ot age) and 3.449 kg
S.E. and 0.672 kg D.P.!kg gain ’tor long late fattened lambs
(from 32 to 40 weeks of age).
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Carcass evaluation:
6. Average slaughter (fasted) weight was )l.JJ kg for
lambs of the l~ feeding regime (fattened from 16 to
24 weeks), 43.75 kg for lambs of the 2nd feeding regime
(fattened from 24 to 32 weeks), 50.50kg for lambs of
the 3rd feeding regime (fattened from 32 to )6 weeks) - and 5:9.25 kg for lambs of the 4!!! feeding regime (fattened
from 32 to 40 weeks).
7. Means of live condition score for the same experimental
groups in the same order were 2.66, 4.08, 4.50 and
4.00. The corresponding averages were 2.84, 4.17, 4.50
and 5.60 for carcass oQDtarma~aa aoare.Effects of teeding
regime on both live condition score and carcass conformation
score were statistically highly significant
(P 4!.0. 01) •
t
~ Hot carcass weight averaged 14.46, 20.64, 24.64 and
28.54 kg tor lambs of the l~, 2B!, 3~ and 4!a teeding
regime, respectively. Dressing percent for lambs of the
4 feeding regime in the same order was estimated as 46.10,
47.10, 48.80 and 48.10 ~ when estimated relative to the
slaughter weight and as 53.30, 51.BO, 54.50 and 57.20 ~
when estimated relative to the empty ~od1 weight. Differences
due to feeding regime etfects were proved to be
highly significant (P L. 0.01) tor hot carcass weight and
only significant (P~ 0.05) for dressing percent 8Ta1uated
relatiTe to empty bod,. weight.
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9. Prime cuts on the average amounted to 68.10, 61.10,
64.00 and 62.90 % of the hot carcass when estimated for
lambs of the 1l!1, 2B2-.,3~ and 4!1! feeding regime, the
differences were highly significant (P L 0.01).
10. The proportion of lean content in the 9 - 10 - 11
rib cut averaged 64.0, 59.8, 58.6 and 60.2 % of lambs of
the 1!1, 2nd, J~ and 41B feeding regime, respectively.
The corresponding estimates were 17.5, 20.40, 24.70 and
25.60 % for fat content and 18.10, 19.40, 16.40 and 14.0~
for bone %. Differences in these traits due to feeding
regime did not attain significances except for bone content
(P L 0.01).
11. ~. dorsi index and area differed with feeding regime,
the differences were not significant tor the index but proved
so for the area. Fat thickness on~. dorsi and on rib
varied with feeding regime but without significant difterenees.
12. Carcass evaluation was the best for lambs ot the 3rd
feeding regime.