Fodder silo

What is fodder silo meaning?

A word silo refers a structure used for storing the bulk materials.

In agriculture sector, silo are used for storing the grain and also for storing fermented feed known as silage. Green fodder produced in season needs to conserve for supply in off season so that animals can get the regular supply of feed.

Fodder crops which are high in soluble carbohydrates are incubated after chaffing for a period of 45-50 days under anaerobic conditions. Sugars present in fodder get converted in lactic acid which acts as preservative and good source of readily fermented sugars for rumen (First stomach of a ruminant) microbes.  

Good quality silage then produced if proper anaerobic conditions are maintained. If proper anaerobic conditions not maintained, silage produced would have butyric acid which imparts off flavor to silage.

Maize, sorghum, pearl millet, hybrid napier are some of suitable crops for silage making. For making silage we need silo (surface or trench), Farm machinery such as tractor, trailer, chaff cutter etc, For medium class farmers 5-6 MT surface silos (manually pressed) need approximate Rs 25,000 and another approximate 25,000 for chaff cutter.

How to make silage?

Silage making is described step by step as follows.

• Construct the surface/trench silo (Silage storage structure), In one m ³ space, 500-600 kg green fodder can accommodate.
• Wilt the harvested fodder to bring down dry matter to 30-35 per cent.
• Chop the fodder in small pieces of 2-3 cm size.
• Fill chopped fodder into the silo and press in silo layer by layer of 30-45 cm. This filling and pressing process should completed as fast as possible.
• Seal the silo with thick polythene sheet.
• Put mud layers, sand bags on polythene sheet to prevent air flow beneath the sheet.
• Open silo for feeding after 45 days.

Silo can be open from one side and after taking out silage, it should close properly. Silage is substitute for green fodder and can be fed to animal initially 5 kg per animal to adjust the animals on silage feeding.

Silo are of following types:

• Conventional upright (Tower) silos
• Pit silos
• Horizontal silos (These are further classified as either trench silo i.e. Below ground level, or Bunker silo i.e. above ground level

• Conventional upright (Tower) silo: These are circular in shape and fitted with number of doors about 2 sq. ft. approximately every 6 ft. up on one side of the silo. The size varies from about 12-20 ft. in diameter and 40-80ft. in length. For effective preservation of silage, the forage should contain between 25 and 35 per cent dry matter.
• Pit silo: Pit silo is like tower silo in shape, but inverted into the ground. It looks like a well. Pit silo can made at those places where the water table is low so that silo will not fill with water.
• Horizontal silo: 1)Trench silo: A trench silo should be wider at the top than at the bottom, and the bottom should slope away from one end. This is comparatively low cost silo and can be constructed quickly. 2) Bunker silo: These silos are constructed above ground and need less labour.

For designing silo following values are assumed.

• Rate of removal of silage – 10 cm/day
• Silage fed per day       -3 kg/100kg of body weight
• Maximum diameter     –  6 m
• Depth                        –  2-3 times diameter
• 1m³ of silage              – 650 kg

For more reading and silo design problems click on below link of ICAR e course

http://ecoursesonline.iasri.res.in/mod/page/view.php?id=622