Nutritive value of spirulina as livestock feed in the sultanate of Oman

Abstract EN

A study was carried out to evaluate the nutritional value of spirulina (Arthrospira platensis) to determine its potential use for feeding livestock in Oman.

Spirulina was grown in wooden cubicles and harvested after 10 days.

One batch of spirulina was dried by centrifugation (CS) and the other was dried in an oven without centrifugation (NCS).

Samples were analyzed for dry matter (DM) and proximate chemical components.

An in vitro assessment was carried out to measure gas production and in vitro DM degradability of spirulina.

The DM was 56.1 and 57.1% in CS and NCS, respectively.

The proximate composition for CS and NCS as a percentage of DM, respectively was: 60.8 and 62.5 for crude protein (CP); 0.97 and 1.05 for Ether extract (EE); 6.35 and 7.55 for ash.

The CS and NCS contained: 0.25 and 0.37% DM Acid Detergent Fiber (ADF) and 1.03 and 1.92 % DM Neutral Detergent Fiber (NDF), respectively.

The gross energy (cal/g DM) was 5730 and 5629 in CS and NCS, respectively.

The CS produced more in vitro gas (73 and 71 ml/200mg DM) from 12 hr until the end of the experimental period (96 hr) compared to the NCS (51 and 48 ml/200mg DM), respectively.

The CS had significantly higher metabolizable energy (ME) (approximately 12 MJ/kg DM) than NCS (about 9 MJ/kg DM).

CS had significantly higher (81 and 79%) Organic Matter Digestibility (OMD) than NCS (61 and 58%).

The CS had significantly higher Short Chain Fatty Acids (SCFA) (1.7 and 1.6 µmol) than NCS (1.2 and 1.1 µmol).

It was concluded that spirulina is an excellent source of protein and can be used after drying as a potential animal feed.

There was little effect of the method of drying of spirulina on its chemical composition or digestibility.