Microbial Community Management in Aquaculture

Microbial Community Management in Aquaculture

Procedia Food Science, Volume 6, 2016, Pages 37-39
P. Bossier, P. De Schrijver, T. Defoirdt, H.A.D. Ruwandeepika, F. Natrah, J. Ekasari, H. Toi, D. Nhan, N. Tinh, G. Pande, I. Karunasagar, G. Van Stappen

https://doi.org/10.1016/j.profoo.2016.02.007

Under a Creative Commons license

The expansion of the aquaculture production is restricted due to the pressure it causes on the environment by the discharge of waste products in the water bodies and by its dependence on fish oil and fishmeal. Aquaculture using bio-floc technology (BFT) offers a solution to both problems.

All biofloc size classes were consumed and utilized by the shrimp, tilapia and mussel. The highest retention of nitrogen in the animal body, however, was consistently originating from the bioflocs larger than 100μm

Survival in the [immunity] challenge tests with shrimp from the biofloc [fed] groups, was also significantly higher compared to the positive control.

Rather than trying to control microbial community composition, microbial activity can be steered. The disruption of quorum sensing, bacterial cell-to-cell communication, has been suggested as an alternative strategy to control infections in aquaculture 5.

Recent studies also indicate that opportunistic aquatic pathogens[…]are also able to sense host clues such as stress hormones.

 

Excretion of dissolved organic carbon by phytoplankton of different sizes and subsequent bacterial uptake

Malinsky-Rushansky NZ, Legrand C
Excretion of dissolved organic carbon by phytoplankton of different sizes and subsequent bacterial uptake
MEPS 132:249-255 | Full text in pdf format
doi:10.3354/meps132249

One of the more-hidden angles of our reef world.

EOC [excreted organic carbon -Ed) may be important as a source of primary growth substrates for free-living bacteria (Larsson & Hagstrom 1982).  The importance of microbial food chains parallel to the conventional grazing ones in aquatic food webs is now recognised (Azam et al. 1983).  The significance of phytoplankton excretion as contributor to the ‘microbial loop’ has been studied (Cole et a.1. 1982, Brock & Clyne 1984).  EOC contributed to about half of the bacterial carbon requirement in some environments (Larsson & Hagstrom 1982).  Some studies suggested that a considerable amount of the annual primary production passed through the bacterial component (Brock & Clyne 1984),and bacterial production averaged 20% of planktonic primary production (Cole et al. 1988).

 

Impacts of nutrient enrichment on coral reefs: new perspectives and implications for coastal management and reef survival

Impacts of nutrient enrichment on coral reefs: new perspectives and implications for coastal management and reef survival

Current Opinion in Environmental Sustainability, Volume 7, April 2014, Pages 82-93
Cecilia D’Angelo, Jörg Wiedenmann

http://doi.org/10.1016/j.cosust.2013.11.029

This article is in the Creative Commons.

This is a really nice review article that touches on many areas that are important to us as reefers.  As a result, it has a GREAT collection of citations that are pretty directly applicable to us and our situation.

A few quotes to whet the appetite – then go read!

We have recently shown that increased nutrient levels might not negatively affect the physiological performance of zooxanthellae as long as all essential nutrients are available at sufficient concentrations to ensure their chemically balanced growth 28.  These results could explain why some reefs and the nutritional status and metabolism of their inhabitants do not always show negative responses to eutrophication [29• ;  30•], at least in the absence of temperature and light stress.

We’ve already been making use of this fact….when you’re done reading this article, check out our post: A Nitrate Dosing Calculator For Better Tank Health (And Better Coral Color!)

Another tidbit from the article:

Most recently, however, we could demonstrate that corals exposed to elevated nitrogen levels were more susceptible to bleaching when exposed to heat and light stress [28]. Interestingly, the detrimental effects observed in these experiments could be attributed to the relative undersupply of phosphorus that resulted from the enhanced demand of the proliferating zooxanthellae population rather than to the elevated nitrogen levels themselves (Figure 1 ;  Figure 2).

 

We’ve been promoting this information (at least here on the blog) for quite a while now.

Phosphate Excretion by Anemonefish and Uptake by Giant Sea Anemones: Demand Outstrips Supply

Phosphate Excretion by Anemonefish and Uptake by Giant Sea Anemones: Demand Outstrips Supply

Authors: Godinot, C.; Chadwick, N. E.
Source: Bulletin of Marine Science, Volume 85, Number 1, July 2009, pp. 1-9(9)
Publisher: University of Miami – Rosenstiel School of Marine and Atmospheric Science

(Also on ResearchGate: Phosphate excretion by anemonefish and uptake by giant sea anemones: Demand outstrips supply)

Full article avalable.

We conclude that under laboratory conditions, anemones absorb phosphate up to 6.6× faster than the rate at which it is excreted by their anemonefish, and thus fish do not appear to provide sufficient phosphate to their hosts through this pathway. Anemones may get most of their phosphorus via ingestion of fish feces and/or mucus, or via the ingestion of prey.

Folks should consider growing anemones if they have phosphate issues!

This is also consistent with info here:

Fish foraging behavior changes plankton-nutrient relations in laboratory microcosms

Fish foraging behavior changesplankton-nutrient relations in laboratory microcosms

NOVALES-FLAMARIQUE, I., S. GRIESBACH, M. PARENT, A. CATTANEO, AND R. H. PETERS, Limnol. Oceanogr., 38(2), 1993, 290-298

Full article (PDF): http://aslo.net/lo/toc/vol_38/issue_2/0290.pdf

To demonstrate that the effects of higher trophic elements on plankton in laboratory aquaria are not simple top-down or bottom-up processes, we measured phosphorus and chlorophyll concentrations in replicated month-old aquaria undergoing one of five permutations involving three fish species, Daphnia pulex, and algae.

Seems like this could be useful in managing tanks.

The response of the scleractinian coral Turbinaria reniformis to thermal stress depends on the nitrogen status of the coral holobiont

Eric BéraudFrançois GevaertCécile RottierChristine Ferrier-Pagès

Overall, results obtained in this study have shown that phosphate enrichment mainly affected the coral symbionts, by decreasing their C:P and N:P ratios, while increasing their carbon, nitrogen, and phos- phorus contents, as well as their specific growth rate, maximal photo- synthetic efficiency of the PSII, and rate of photosynthesis normalized to chlorophyll content. Phosphate enrichment also affected the skele- tal compartment, by increasing the skeletal growth and the P/Ca ratio. Conversely, few changes were observed in the animal host tissue.

The Godinot et al., 2011 citation leads to “Tissue and skeletal changes in the scleractinian coral Stylophora pistillata Esper 1797 under phosphate enrichment” is also interesting.

Here are the authors’ own highlights:

  • We examined P enrichment’s impact on calcification and tissue composition in corals.
  • We assessed a possible phosphorus limitation in symbiotic zooxanthellae.
  • Photosynthetic efficiency, CNP contents, and specific growth of symbionts increased.
  • Results indicated a phosphorus limitation of zooxanthellae growth in hospite.
  • Skeletal growth rates and phosphorus incorporation into the skeleton also increased.

We’re making a new post for that story now.  🙂

Extracoelenteric zooplankton feeding is a key mechanism of nutrient acquisition for the scleractinian coral Galaxea fascicularis

Extracoelenteric zooplankton feeding is a key mechanism of nutrient acquisition for the scleractinian coral Galaxea fascicularis

Tim WijgerdeRara DiantariMuhammad Wahyudin LewaruJohan A. J. VerrethRonald Osinga

Continue reading “Extracoelenteric zooplankton feeding is a key mechanism of nutrient acquisition for the scleractinian coral Galaxea fascicularis”