The document discusses using herbal medications to improve the immune defenses of farmed fish. It notes that diseases have increased with intensive farming and climate change. While antibiotics are commonly used, they can cause resistance and residue issues. The document reports on a study showing herbal immersion with AquaHerb for 24 hours improved survival rates against bacterial infection in several fish species by 80-90%. It explains that saponins and tannins in AquaHerb enhance immune response and appetite. A field trial also showed AquaHerb modulates immune functions by increasing leukocytes and monocytes. The results prove the efficacy of herbal immersion in reducing fish mortality from Vibrio bacteria.

1. HERBAL MEDICATION TO IMPROVE IMMUNE
DEFENCES OF FARMED FISH
By:
Romi Novriadi and KB Haw
Today, the number of diseases as an effect of an equilibrium disruption between the
hosts (animals), pathogens and environment has grown simultaneously and become a major
constraint to the sustainability of aquaculture production. With changing climatic conditions
and the application of (super)intensive systems, the fish become more easily succumb to
diseases and will affect their survival and growth performance. Improvement of health
management and husbandry practices can be proposed as an effective approach to reduce the
stressful events and mortality in aquaculture system.
Among the conventional treatment, the use of chemotherapy (read: antibiotics) is quite
popular to treat or prevent the diseases infections. However, the frequent use of
chemotherapeutic agents has stimulated the development of bacterial resistance. Another
problem created by unrestricted use of antibiotics is the presence of residual antibiotics in
commercialized of aquaculture products. This problem has led to allergy and toxicity in humans
and resulting in shifts in the diversity of the microbiota due to the permanent existence of large
amounts of antibiotics in the environment. Consequently, novel preventive approaches in
aquaculture are urgently needed. In this context, the use of medicinal herbs can be used as one
alternative strategy and can act as an immunostimulant, conferring early activation to the non-
specific defense mechanisms of fish and elevating the specific immune response.
Romi Novriadi is Researcher at Balai
Perikanan Budidaya Laut Batam,
Ministry of Marine Affairs and Fisheries,
Republic of Indonesia, KB Haw is
Product Engineer at Aqua cultural Fresh
and Marine Exploratory, Singapore
Romi Novriadi KB Haw

2. Tackling Bacterial Infection
In a controlled bacterial infection study with Vibrio parahaemolyticus in Tiger grouper
Epinephelus fuscoguttatus, Asian Seabass Lates calcarifer and Silver pompano Trachinotus
blochii, it was confirmed that 24 hours immersion with commercial herbs (AquaHerb) have
been successfully provide a better resistance and survival in Tiger grouper by 82,67±2%, in
Asian Seabass by 84.67±0.67 % and in Silver pompano by 88.89±1.39 %. According to several
researcher, studies confirm that the use of purified plant extract and long term of herbal
application were able to enhanced the survivability of treated fish against bacterial infection.
Figure 1. AquaHerb use at several marine fish species was able to induce survival rate against V.
parahaemolyticus infection at 105
cell/ml
The beneficial effects of these commercially available AquaHerb was also strengthened by
the presence of dried peat, dried Leaves Saponin and dried roots tannin in their composition.
Even saponin have been reported to have damaging effect on the fish respiratory epithelia, but
in low concentration, saponin based adjuvant have the unique ability to stimulate the cell-
mediated immune system and to enhance the antibody production. This is confirmed by Chavali
reported that saponin either as crude mixtures or as a purified compounds was able to increase
the immune cell proliferation. Moreover, the administration of saponin to the infected fish
have been found to have a detrimental effect to protozoa, mainly due to the virucidal activity

3. and antifungal activity contained in their active substance. Our results are in accordance with
the recent findings that indicated the prior administration of saponin contained in the
AquaHerb before challenged with V. parahaemolyticus was able to enhance the Tiger grouper,
Asian seabass and Silver pompano immune system in comparison to control. In addition to
saponin, the use of dried tannin contained in AquaHerb was also useful for the prevention of
piscine diseases and off-flavor in fish and did not harm the productive performance. Based on
the field observation, the complementary of tannin and saponin will enhance their immune
system and the appetite of fish after medication. However, all this benefits effects of these
active substances will be only obtained if given in the appropriate dose.
Improved Cellular Immune Response
The field trial also showed that AquaHerb were able to modulate some parameters of
non-specific immune functions of several marine fish species. The non-specific defence
mechanisms of fishes include leukocyte function, neutrophil activation, monocyte together with
initiation of other inflammatory factors. The use of AquaHerb showed an elevated number of
leukocyte over the whole period of the experiment in comparison to control. In the presence of
V. parahaemolyticus, 24 h of AquaHerb conditioning treatment were able to significantly
improved the fishes survival in comparison to other conditioning treatment. AquaHerb
conditioning treatment was also able to increased total percentage of monocytes in the
presence or absence of pathogen. Numbers of monocytes become more important because
they act as the main cells of non-specific defense system shifts from blood cells into tissue and
become macrophages that are capable to kill a variety of pathogens including bacteria.
“The result proved the efficacy of herbal immersion on the fish by reducing the number
of mortality” says Prof. Harry Agusnar, Professor on Analytical Chemistry, University of
Sumatera Utara. Based on the experimental results, it was obvious that the provision of herbal
extract is an effective immunostimulant against bacteria from the Vibrio genus that are most
frequently associated with mortalities in marine fish. The unique composition of AquaHerb
added to the rearing water appear to improve the immune status and disease resistance of fish.

4. Figure 2. Tiger grouper Epinephelus fuscoguttatus immersed with AquaHerb for 24 hours
This progress in the field of diseases treatment was further extended in February this
year when the next generation of AquaHerb was investigate to overcome the virus infection in
marine fish, especially to eliminate the iridovirus infection. The social campaign of using herbal
medicine and avoid the use of antibiotics will be intensively performed in several Asian
countries as our responsibility to support the eco-friendly of aquaculture industry and
generated the healthy product for the people.