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Sericulture in Nigeria after many years of abandonment has taken a new dimension in
Akure, Ondo State, where a hybrid of local and exotic cross of Bombyx mori is being
adopted. This study was carried out in the Federal University of Technology, Akure with the
aim of investigating the egg laying capacity and hatchability of the breed under different
temperature ranges and mating duration. Eggs of the breed were reared to adult under normal
conditions. 1,230 cocoons were selected and adult moths were allowed to emerge, 800 of the
adults that emerged were randomly selected (400 males and 400 females). 30 adult males and
female moths each were paired per thermal treatments at 41 plusminus 1°C, 31 plusminus 1°C, 28plusminus 1°C, 10plusminus
1°C and 4 plusminus 1°C) and each of the 30 pairs were exposed to 10minutes, 30 minutes, 4 hours
and 12hours mating duration. For 10mins and at all the different temperatures, fecundities of
the silkworm were not significantly different (F1,14 = 0.743, Sig = 0.404, p > 0.05) but
hatchability were significantly different (F1,14 = 10.310, Sig = 0.007, p < 0.05). For 4 hours
mating duration, under variable temperature of 4°C, 10°C, 28°C, 31°C and 41°C, number of
eggs laid were significantly different (F1,14 = 19.373, Sig = 0.001, p < 0.05) and hatchability
(F1,14 = 20.888, Sig = 0.001, p < 0.05). Hatchability of eggs at all the temperature were
significantly different (F1,4 = 134.15, Sig = 0.000 p<0.05). At ambient temperature 28 plusminus 2°C,
hatchability in 10mins, 30mins, 4hours and 12hours were recorded as 78.8, 82.7, 88.24 and
67.8% respectively. More eggs were laid and hatched under a mating duration of 4 hours.
Thermal stress accelerates the entire metabolism and the rate of living of the silk moth.
Hence, it is important to conduct silkworm breeding activities under optimum temperature
and mating duration conditions.
Keywords: Fecundity; Copulation; Hatchability; Bombyx mori; Cocoon; Eggs