An on-farm demonstration found sawdust, peanut hulls and sorghum stubble, as well as barley straw, to be suitable bedding materials for pigs. It also found growth rates to be within expectations. Peanut hulls and sawdust provided the driest surface, though extra bedding can be added to reduce litter dampness. The demonstration also found combinations of litters, such as sawdust and sorghum stubble, to be useful.
Bedding makes up a high proportion of the cost of contract growing and can easily reduce the profit margin. The key issues to consider when choosing bedding are absorption capability, its ability to remain evenly distributed throughout the shed and the overall cost per batch of pigs.
The rankings shown in Table 1 relate only to this situation, as both the unit cost and availability of bedding materials vary between locations and depend largely on product demand from other industries. In this project, sorghum stubble was available on farm, making it the most economical of all the litters evaluated. If shredded newspaper was available at a reasonable cost, it would also have potential.
At the end of the 10-week trial using 26 bales of straw, two-thirds of the pen was a damp dunging area and one-third, at the feeder end, was relatively free of moisture. Barley straw had a tendency to clump and appeared to remain damp on the surface.
Initially, 65 bales of paper were used and then another 5 bales were added. However, after two weeks, only about 2 cm depth of litter remained. The paper tended to compact and reduce the effective volume available. The additional amount of paper required to bring the depth of litter from 2 to 20-30 cm was considered too great a cost at $13 per bale (2001). Therefore the paper section of the trial was terminated.
Peanut hulls yielded almost identical results as the barley straw pen, with approximately 20-40 cm depth of litter left at the end (from the initial 40 m³ and an additional 9 m³, totalling 7 t) and a similar pattern of moisture. In contrast to barley, peanut hulls and sawdust absorbed more moisture, leaving the surface relatively dry. In this trial, peanut hulls were the second most economical option as there was a local supply.
Initially, 40 m³ of hardwood sawdust was used to provide a depth of 40 cm. After 10 weeks, another 2 m³ of extra material was added. The condition of the litter was similar to that of barley straw and peanut hulls, though it had a drier surface than the barley straw. Sawdust tended to produce large amounts of dust, potentially posing a health problem for workers and animals.
A total of 25 bales of sorghum were used. At the end of the 10 weeks, bogginess with some leakage was noted. The composted end material was of a better quality than the other litters. Additionally, the low cost of the sorghum, due to being sourced on farm, would enable the addition of more stubble or another litter material, such as sawdust, towards the end of the batch, resulting in a drier and still economical result.
|Material|| Approximate amount|
(kg / pig / day)
|Advantages||Disadvantages||Ranking in this situation|
Good moisture-holding capacity.|
|Barley straw||0.4||Possible on-farm source||Damp surface||2|
|Sawdust||0.54||Good moisture-holding capacity||Dustiness||2|
|Sorghum stubble||0.38||Possible on-farm source||Boggy; some leakage at end of 10 weeks||2|
|Shredded paper||-||Unknown: used for too short a time||Cost. Compacted quickly||3|
The project location
Queensland Government officers and Kewpie Group growers undertook this Group Demonstration Project in a commercial production environment in South Burnett in 2001. Australian Pork Limited (APL) partly funded the project.
Two 25 m x 9 m shelters were used, place in an east-west orientation and divided longitudinally into two pens by a solid partition. Feed and water facilities were located on concrete pads at the eastern ends. Each shelter housed 180 pigs from 10 weeks of age until around 23 weeks. The pens were used as experimental units.
- Payne, H, Mullan, B & Trezona, M 2000, 'Review of alternative housing systems for pigs'.