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Academic Research Journal of
Agricultural Science and Research |
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Academic Research Journal of Agricultural Science and Research Vol. 5(5), pp. 350-357. September, 2017. ISSN: 2360-7874 DOI: 10.14662/ARJASR2017.041 Full Length Research Determination of optimum mulberry silkworm larvae bed spacing on feeding tray using shelf rearing technique
Abiy Tilahun*, Ahmed Ibrahim, Kedir Shifa and Metasebia Terefe.
Ethiopian Institute of Agricultural Research Center, Melkassa Agricultural Research Center, P.O. Box-436, Melkassa, Ethiopia
Accepted 14 August 2017
Bed
spacing is an important silkworm rearing practice to ensure the hygiene
of silkworms. Different stages of silkworms require different bed space.
As worms increase in size, there is overcrowding and overlapping each
other that leads to underfeeding, creating a microclimate for disease
spread and could also lead to suffocation. Hence, appropriate bed
spacing is essential to silkworms, to keep the worms healthy and
productive. The treatments used for examining the appropriate bed
spacing of young and medium aged silkworm larvae were 1200, 1000, 800,
600, 400 and 200 per feeding tray (60cm X 90cm size). Another
arrangement of bed spacing used for examining the mature aged silkworm
larvae was 600, 500, 400, 300, 200 and 100 per feeding tray (60cm X 90cm
size) to evaluate the effects of mulberry silkworm bed spacing on
different silkworm strains.1st and 2nd larval instars as young age, 3rd
and 4th larval instars as medium age, 5th larval instar as mature age
were considered in the study. Observations on larval mortality, weight
of larva and shell and silk ratio from different silkworm strains were
carefully noted for each treatment. Statistically significant variation
in mean larval mortality rate among bed spacing was observed in young,
medium and mature silkworm larval stages of silkworm strains. Larval
mortality rate was significantly (P < 0.05) reduced when young, medium
and mature larval stages of mulberry feeding bivoltine silkworm strains
(Korean bivoltine and Kenyan bivoltine silkworm strains) reared in a
group of 400 to 1000 worms, 400 to 800 worms and 300 to 500 worms
respectively in a 60 cm X 90 cm feeding tray of shelf rearing method. A
significant (P < 0.05) reduction of larval mortality was recorded from
mulberry multivoltine Vietnamese silkworm strains in a bed spacing of
400 to 1200 larvae for young larval stages, 400 to 1000 larvae for
medium larval stages and 300 to 600 larvae for mature larval stages.
Bigger Larval weight, bigger shell weight and higher percentage of silk
ratio are important cocoon yield quality parameters for silkworm
strains. Significant (P < 0.05) variations were observed among
population densities for these important variables in all the tested
silkworm strains.
How to cite this article: Tilahun A, Ibrahim A, Shifa K, Terefe M (2017). Determination of optimum mulberry silkworm larvae bed spacing on feeding tray using shelf rearing technique. Acad. Res. J. Agri. Sci. Res. 5(5): 350-357
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