Effects of carbohydrate addition frequencies on biofloc culture of Pacific white shrimp (Litopenaeus vannamei)

Abstract

In Pacific white shrimp culture, adding organic carbohydrate to the pond besides feed improves water quality and shrimp performance. While the feeding frequency has significant effects on shrimp production, how often carbohydrate should be added remains unknown. This research investigated the effects of carbohydrate addition frequency of 1, 3, and 6 times per day on Pacific white shrimp production. Tapioca powder was used as carbohydrate source to maintain an input C:N ratio of 12. The same daily ration of tapioca was applied, but divided into equal portions according to the application frequency. The shrimp performance was better in carbohydrateadded systems than in a conventional system without additional carbohydrate, but the carbon retention efficiency was lower. Splitting daily dosage of carbohydrate into more frequent additions had no significant effect on Pacific white shrimp performance, and carbon and nitrogen retentions. A carbohydrate addition frequency of once per day is recommended for good performance of Pacific white shrimp in biofloc rearing systems.

Optimized Utilization of Organic Carbon in Aquaculture Biofloc Systems: A Review

“…Importantly, the conventional commercial-feed treatment retained 62% of the total carbon input, while in carbon-added treatment, this was 26-31%. In other words, regardless of the carbon addition frequencies, biofloc reared with Pacific white shrimp showed double carbon loss compared to conventional cultivation [73]. Similarly, Hu et al [64] clarified that the employment of soluble starch to a tilapia-based BFT system increased the daily CO 2 emission by 91.1% compared to the feed only.…”

“…It is evident that carbon addition reduced the carbon retention efficiency of the total carbon input compared to the commercial feed alone (Table 2). Nevertheless, the manipulation of the addition method or frequency failed in elevating the carbon utilization as expected [53,73]. By contrast, the integration of BFT with denitrification and aquaponics recycling nutrients for multiple uses seems plausible to reduce carbon emission for sustainable aquaculture production [67,76], and further research is thereby warranted.…”

“…Additionally, few studies have investigated the carbon addition frequency for the optimization of addition strategy. As reported, splitting the daily dosage of the carbon source from 1 to 3 and 6 times per day had no significant effect on Pacific white shrimp performance, and carbon and nitrogen retentions in BFT [73]. The low carbon addition dose could also help to avoid sudden drops in oxygen concentrations caused by bacterial consumption, thereby maintaining a stable environment for the animals reared in the system and improving survival rates [91].…”