The use of plastic tubes is one of the most suitable methods for smallholder dairy farmers who want to make limited quantities of silage.
Plastic silage bags are an economical alternative to traditional silage storage systems, such as pit silos.
It is an effective way of preserving feeds with minimum nutrient loss. The anaerobic environment that is created prevents spoilage due to growth of yeasts, moulds and adverse bacteria while maintaining essential proteins and nutrients.
Allows farmers to store silage anywhere they need.
The silage is completely sealed in the bag, which means all the lactic acid is retained in the silage, unlike in pit silage, where it seeps out through the bottom of the pit as effluent. This compensates for the longer pieces of forage and poorer compaction than that found with silage machinery, so the quality of the silage is just as good.
Ensiling in a bag avoids the hard work of having to remove silage, as it has to be from a pit, where it is dug out every day.
Because the whole bag is fed to the animals, it means the rest of the silage, which is in the other bags, is not exposed to air at removal and is, therefore, unspoiled. Much of the silage in pits has been found to be spoiled due to poor sealing and exposure to air every day when the silage is removed for feeding.
The bag is easily stored and easily portable so that any member of the family can carry it to the feed trough for the cow.
Disadvantages of plastic tube silage
Containment and disposal of the plastic, once silage is removed from the bag, is a challenge.
There is need to chop the green mass, as chopped material tends to make much better silage, because more air can be squeezed out of it during the packing process and the small pieces cannot puncture the bag.
Most losses of silage during the process occur due to unnoticed bird/rodent damage to the bags, resulting in spoilage loss and too wet (gaseous/seepage losses) or too dry silage (spoilage).
A plastic bag (600-800mm) of 1.5 metres can compact 50-70kg of silage, depending on material used.
The cost of producing 1kg of elephant grass silage using a plastic bag silo and using maize bran is about sh250 per kg.
Silage bags, especially silage from maize fodder, attracts rodents. Once in, rodents could easily hide between bags, chewing through the plastic bags, resulting in aerobic spoilage.
Monitor the silage bags on a regular basis for any rodent, bird or livestock damage.
Do not use chemical means for rodent/pest control, as life expectancy of the plastic is reduced when exposed to chemicals.
Storage shelves can be constructed with stands in order to keep the store off the ground.
Utilisation of silage
Silage is ready for feeding at least 30 days after making it.
Silage should be fed as soon as possible, preferably within a few hours after opening the silos.
Silage cannot replace concentrates. Therefore, supplement your dairy cows with concentrates when using silage.
To avoid off flavours in milk, silage should be fed to lactating cows at least two hours before milking or after milking the animals.
After feeding, the feed troughs must be cleaned to remove any remaining silage, which will spoil or contaminate the next feed.
Each time after you open a silage bag and remove some silage, expel air from the bag and then tie the remaining silage tightly to avoid spoilage.
Damage on silage bags can happen due to bad weather and rodents, which can puncture the plastic covering. For maintenance, the following recommendations should be followed:
Inspect the bags regularly and, if possible, mend the holes.
Do not allow animals to climb the bags.
Number and date the bags for easy identification and record materials.
Do not leave the silage bags open overnight.
If damage is extensive, the silage needs to be re-bagged as soon as possible;
If maintenance is appropriate, after three-five weeks, excellent lactic acid fermentation will result and bags kept well for six months, with no or little fungal spoilage.
After removing the silage, the bags must be carefully washed, dried and stored in a safe place for use.