الفهرس 
REVIEWOF LITERATUREOnly 14 pages are availabe for public view
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Abstract
Summary
The present study aims to evaluate the nutritive values of five mulberry varieties used for feeding the silkworm, Bombyx mori L. larvae from the first till the 5th instar through studying their effect on biological, productive and biochemical changes, also through the related leaves consumed to the production of cocoon. Also, determining the phenolic content of these leaves and the antioxidant activities and their importance to the silkworm besides for further use of these leaves after the rearing season.
The obtained results could be summarized as follow:
I- Mulberry varieties.
I.1-Chemical analysis of the examined mulberry leaves varieties.
The mean moisture level of the leaves is higher in Kokuso-27 and the least moisture content was in Arandaly. Also, total protein content is relatively more in Sh2xlunlog comparing to the other varieties, while Kearyang-ppong was the highest in carbohydrate content and the least in Sh2xlunlog.
The Kanava-2 variety registered the highest level in total lipid content followed by Sh2xlunlog, while the other mulberry varieties registered less level of lipid content.
Total ash content (minerals) was the highest in Kokuso-27 while the least content was found in Kanava-2 .
Total fiber content revealed reverse trend to total protein content, with the highest level in Kanava-2 and the least level in Kokuso-27and Kearyang-ppong .
I.2- Phenolic contents and antioxidant activities:
The obtained results shows that the highest total phenolic contents were in Sh2xlunlog followed by Kokuso-27 while the least values were determined in Kearyang-ppong and Kanava-2.
The antioxidant activities in Sh2xlunlog followed by Kokuso-27 were the highest, while the least in Kanava-2.
II- Effect of feeding the five mulberry varieties on silkworm larvae:
Maximum total larval duration was recorded in Kanava-2 and Kearyang-ppong fed to larvae, while Kokuso-27 and Sh2xlunlog recorded the least larval duration.
Weight of young and grown instars (4th and 5th instars) fed on the different mulberry leaves differed significantly between the varieties. The heaviest weight was with Kokuso-27, followed by Sh2xlunlog.
Effective rate of rearing (ERR%), recorded the highest percentage with each of Kokuso-27, Sh2xlunlog and Arandaly during young and grown larvae.
II.1- Utilization of different mulberry leaves by the silkworm B. mori L.
II.1.a- Weight of food consumption:
The quantity of food consumed differed between the mulberry varieties, maximum mean consumption were recorded with Kokuso-27 and followed by Sh2xlunlog during the 4th and 5th instars, respectively.
While the minimum mean consumption were found with Kanava-2 for the same larval instars, respectively.
II.1.b- Digestion (A.D) and Digestibility %:
The highest digestion (A.D) and digestibility % were obtained in Kanava-2 feeding and during 4th and 5th instars, respectively. While, the least digestion (A.D) and digestibility % were recorded for Kokuso-27 feeding for the same above instars, respectively.
II.1.c-Efficiency of conversion of ingested food (E.C.I%):
The highest (E.C.I%) values were detected with Kokuso-27 feeding followed by Sh2xlunlog during 4th and 5th instars, respectively, while Kanava-2 was the least values.
II.1.d-Efficiency of conversion of digested food (E.C.D%):
The values of (E.C.D%) follow the same pattern of (E.C.D.%) comparison of conversion between varieties revealed that there is a considerable increase in Kokuso-27 and Sh2xlunlog varieties in comparison to Kanava-2.
II.2- Effect of feeding the five mulberry varieties on the silkworm pupal stage:
II.2.a- Cocoons characteristic:
The weight of cocoons, cocoon shell, cocoon shell ratio and pupal weight for both female and male showed highest values in Kokuso-27 followed by Sh2xlunlog, while Kanava-2 recorded the least values.
Also, cocooning percentage and pupation rate among the mulberry varieties, feeding on Kokuso-27, Sh2xlunlog and Arandaly induced maximum rate.
II.2.b- Leaf Cocoon Ratio:
The total amount of consumed leaves by B. mori L. larvae to produce 1kg of fresh cocoon was estimated with the five mulberry varieties. The most suitable variety for rearing silkworm Kokuso-27 followed by Sh2xlunlog.
II.3.c- Cocoons technical parameters:
Statistical analysis showed significant differences between Kokuso-27, Sh2xlunlog and other mulberry varieties in the length of filament, weight of filament, size of reeled thread (denier) and silk ratio (recovery). Kokuso-27 and Sh2xlunlog recorded high values of technological parameters, while Kanava-2 recorded low values.
II.3-Effect of feeding the five mulberry varieties on silkworm moth.
II.3.a-Number of deposited egg/ female:
The number of egg / female was recorded for every variety. The results show that there is a significant difference between varieties except between Kanava-2 and Kearyang-ppong.
III- Effect of feeding the five mulberry varieties on silkworm enzymatic activities:
III.1 - Transaminase enzymes:
The two enzymes GOT and GPT proved to be present in the heamolymph in variable amount. GOT activities were higher than that of GPT activities in the heamolymph of larvae fed on all the mulberry varieties.
GOT activity of larvae fed on Kanava-2 recorded the highest value followed by Kearyang-ppong, while Arandaly and Kokuso-27 showed the least values. On the other hand GPT activity recorded higher value with Kokuso-27, while Kearyang-ppong was the least.
III.2 - 3 phosphoglycerate dehydrogenase:
Significant differences in (3-PGD) activity in the heamolymph of larvae fed on the different varieties. The highest level of 3-PGD activity was recorded in the heamolymph of larvae fed on Kokuso-27 followed by Sh2xlunlog, while the least activity recorded with Kearyang-ppong followed by Kanava-2.