Sericulture - Mounting and harvesting methods, Study notes of Biology

Download Sericulture - Mounting and harvesting methods and more Study notes Biology in PDF only on Docsity! Mounting and harvesting Transferring adult larvae to a suitable frame for mounting gives worms a good anchor to build cocoons. At the end of the V stage, on the sixth or seventh day, there is a decrease in the amount of leaf that the larva consumes. The larva starts to crawl in the bed with its head elevated after releasing moist faeces, shrinking in size and turning translucent. These indicate the presence of spinning larvae. After observing those symptoms, the feeding amount should be decreased and the aeration level raised. In order to produce cocoons of high grade. Choosing the right mountages and using them correctly are crucial during cocoon spinning. Mountages refer to the frame utilised by worms to spin their cocoons. The spinning larvae are manually picked up and put on the mountages as they emerge from the rearing bed. Shaking the branches and gathering the larvae en masse makes it simple to separate the worms when they have all reached maturity and are prepared to spin. The spinning larvae are put on mountages made of bamboo or another material. 24°C temperature, 60-65% relative humidity, and sufficient aeration are required for spinning. Incorrect mounting technique and carelessness when mounting mature worms might be caused by defective cocoons. Because of the mounting and spinning requirements, this has an impact on reeling activity and ultimately leads to the manufacture of silk of poor quality. The ideal conditions for spinning a high- quality cocoon are 24 to 26 °C, a humidity of 60 to 70 %, and a current air speed of 0.5 to 1 m/s. As soon as the silk filament comes into touch with air, it begins to dry. Mountages The goal of using mountage is to offer an angular homogeneous space for silkworms, making cocoon development easier. A decent mountage should include the following features: • Enough and consistent cocooning space between frames. • The substance used to build mountages should be able to absorb moisture from urinating. • The material should be inexpensive, long-lasting, and conveniently accessible locally. • Harvesting should be made simpler. • Suitable for simple cleaning, disinfecting, and storage after use. The different kinds of mountages in use are as follows: Bamboo Chandraki: The 'Chandrike' or ‘Chandraki’ is the most frequent type of mountage in India. This consists of a rectangular bamboo mat with a spiral of bamboo tape attached to it. The standard dimensions are 1.8 m x L.2 m. The cape should be 4 to 5 cm wide, and the space between the spirals should be 4 to 5 cm. The key benefits of a 'Chandrike’ or ‘chandraki’ are: • It is easily disinfectable. • It is readily shifted from place to place and stored, and it serves multiple functions in the village. • It is easily constructed in villages where bamboo weaving is widespread, • It allows for the flow of air, allowing the excreta of spinning silkworms to dry fast. Paddy Straw Mountages: • Paddy straw mounting is a traditional method. • It is inexpensive, effective, and produces high yields. • It's a pile of paddy straw. • Because straw absorbs surplus water, the worm may spin with adequate room. • It is inconvenient because cocoons may be crushed. • Harvesting is an issue. Plastic collapsible mountages: The mountage is 2' by 3' and is made of wave-shaped plastic nets. Each mountage has 12 furrows and 11 crests, with combs measuring 2 cm in length. Though cleaning and storage are simple, disposing of urine and litter during the spinning step is challenging, and the rate of faulty cocoons is also significant. • It generates cocoons with superior commercial properties, • It has a longer lifespan.