Rice hulls are a proven good litter material. Where they are regionally available, they are the preferred bedding material for many growers.

Characteristics

Lightweight; Medium particle size; Soft and compressible; Low thermal conductivity; low absorbency (with water being held between particles rather than within them); Good drying rates; High friability if actively managed.

Contaminants and pests

More likely to attract pests during storage prior to use than wood-based (shavings, sawdust) products and is more attractive to rodents and wild birds.

There is no evidence that it is more or less susceptible to litter beetle infestations than other litter bedding material.

Sourcing and pre-treatment

Rice hulls are generally only available within a reasonable transport distance from the rice-growing region of the Riverina. As with straw, there have been issues with a reliable supply at a competitive price in recent years. This is due to severe drought conditions, as there is not only a lack of overall supply, but growers face increased competition from other livestock production (pigs and horse stables). In 2017, the price per cubic metre (m³) on-farm was $15–25.

Ventilation and moisture management

Rice hulls do not require any additional ventilation management due to their large surface area, which promotes rapid drying.

Caking and litter conditioning

As with all bedding materials, it can be susceptible to caking if not managed correctly and/or becomes too wet from chicken excreta, outside moisture or extraneous water from broken/poorly maintained infrastructure, thus conditioning may be required. Due to its good friability and consistency, it is less susceptible to caking than straw.

Litter re-use

Re-use with rice hulls has not been common in Australia, as most re-use has occurred outside of rice-growing areas. It has, however, been successfully re-used overseas.

Spent litter management

Useful as a fertiliser under Australian conditions but will likely have more weed seed contamination than wood-based (shavings, sawdust) products. This, however, can be overcome with effective composting before application.

Rice hulls are more desirable for use in energy generation using anaerobic digestion than timber-based litter, as they will more readily digest than timber. The manure and rice hull component will also generate energy in combustion processes, provided moisture levels are low.