Impact of Cholecalciferol (D3) supplementation on biology and cocoon yield of silkworm, Bombyx mori L.

The impact of different levels of the Cholecalciferol (Vitamin D3) supplementation on silkworm larvae was evaluated by rearing under controlled conditions of temperature, relative humidity and photoperiod (25 ± 1 °C, 75 ± 5 % and 16:08 h of light to darkness ratio, respectively) at Sericulture Research Laboratory, Lahore, Pakistan. Larvae were fed on mulberry leaves of “Chinese Husung” variety supplemented with vitamin ‘D3’@ 0.5, 1, 1.5 and 2 % solutions. Thesignificant increment in larval length (2.81, 4.17 and 5.91 cm in D3 (2%) as compared to 2.69, 3.79 and 5.56 cm in control) were recordedin 3rd, 4th and 5th instars, respectively. The results also delineated significant variations in larval weight (0.39, 1.0 and 2.81 g in D3 (2%) as compared to 0.28, 0.78 and 2.54 g in control, during 3rd, 4th and 5th instars, respectively). Larval foodconsumption recorded during 3rd, 4th and 5th instars showed significantly higher mean values (2.63, 3.23 and 4.43 g in D3 (2%) as compared to control (2.26, 2.60 and 2.74 g), respectively. The dietary supplementation also affected cocoon weight (1.39 g) and Shell Weight (0.33 g) and consequently Cocoon Shell percentage (23.74 %) recorded in D3(2%) in comparison with 1.25 g, 0.24 g and 19.2% in control, respectively. The results indicated improvement in better food consumption, larval weight and length and cocoon production when mulberry leaves supplemented with D3. The study highlighted the significance of dietary supplementation with vitamin D3 of “Chinese Husung” mulberry variety for rearing of silkworm.