Showing posts with label betta splendens. Show all posts
Showing posts with label betta splendens. Show all posts

Research Paper to Read: (2004) Effect of feeding frequency on growth and fecundity in an ornamental fish, Betta splendens (Regan)

Source: ResearchGate.

Takeaways
(1) Two meals per day is the optimum frequency for growth, gonad (a testis or ovary) development, and fecundity (fertility on producing eggs).
(2) Don't overfed (three times per day) your female Bettas as it will increase it's mortality rate and reduce eggs production.
(3) 14 days is sufficient enough for subsequent spawn for a female Betta.

Why this paper?
One of the question when rearing and breeding Betta splendens is how frequent we should feed the fish to achieve optimum growth and speed up breeding. There are many inconsistent advice given by different breeders on the number of times the fish should be fed. Nevertheless, going through scientific literature will give us a baseline to feed our fishes at the optimum level without unnecessary food waste. However, this does not discounts the vast years of experience of master breeders as typical scientific research was done once compare to years of multiple trials and errors of some breeders.

Material and Methods
This experiment includes 375 juveniles Betta of 30 days old with weight of 0.045±0.01 g and lenght of 14.43±2.2 mm (not sure full length of just body only). The fishes were grouped into 15 groups of 25 each with three sets of each feeding frequency as shown below:

(1) One meal in three days (at 6:00).
(2) One meal in two days (at 6:00).
(3) One meal in one day (at 6:00).
(4) Two meals a day (6:00, 18:00).
(5) Three meals a day (6:00, 12:00, 18:00).

Breeding conditions for 77 days, roughly 2.5 months.

(1) 110-l circular cement cistern with measurement of 53.34 x 45.72 cm (the rounded container typically used by Thai Betta farm).
(2) 50l unchlorinated well fresh water. Tank were drained bi-weekly (didn't mentioned how much water)
(3) Temperature averaged 28±1C,
(4) pH 7.8±0.05.
(5) Water hardness 316±15 mg CaCO3/l, ammonia 1.01±0.12 mg/l and DO 4.04 ppm.
(6) Fresh minced beef liver (protein 35.44%, fat 3.86%, ash, 13.91%, and nitrogen free extract 46.79%)

Calculation of each type of measurements as follows:

(1) Growth. Calculation initial dry weight using electrical monopan balance. Five fishes were sacrificed (not sure how). Weight is determined every 14 days.
(2) Gonad. Calculation initial gonad weight using electrical monopan balance and gonadosomatic index (GSI). Three female fishes sacrificed (not sure how) every 14 days.
(3) Spawning. Upon attaining sexual maturity (did not mention when), two pairs of male and females where selected to spawn in a plastic container with water depth of 15cm. Eggs (hatched or unhatched) counted using sterilized needle.

Results
While the growth rate was expected for those with higher frequency feeding, there was no significant differences between two meals and three meals per day. Interestingly result of spawning size. As the result below shown, if the female Betta was overfeed (three meals per day), the eggs production will decrease. We're quite surprised that second and third spawn yields even more eggs after every 14 days.



Discussion
It seemed what we did with our breeding project was significantly not helpful to our female Bettas. To increase eggs productions, we've fed both male and female Bettas four meals per day. The result have shown that overfed actually decreased the eggs production and can cause bloating and dropsy. We've observed some of our female Bettas experienced such symptoms after mating.

Further Questions
(1) The paper did not address the impact of different meal plans for juveniles fish from 1st till 30th day. It only accounts for fish starting for 30 days old.
(2) Why not jar each juveniles fish and measure its growth, gonad development, and fecundity individually in separate container instead of one large 110-l circular cement cistern.
(3) To prevent bloating, some breeders skip Sunday meal so that the fish can fast to clear out all its waste. Will this have any significant differences to the result for those 3 meals per day?

Research Paper to Read: (2018) Minimal water volume for intensively producing male Siamese fighting fish (Betta splendens Regan, 1910)

Source: Research Gate.

Takeaways
(1) 150 mL water volume within 2 - 9 cm depth should be the minimum and optimum water volume to rear individual male Siamese fighting fish.
(2) Jar the fish when it reaches 1.5 months old (6 weeks) and sell it at 4 months old (16 weeks).

Why this paper?
Betta fish (B. splendens) is an aggressive and territorial tropical fish. To defend its territories, a Betta fish will flare its gill and spread its fins. Furthermore, it will bite its intruder. Therefore, upon reaching adulthood, the male Betta will need to be separated and jarred into separate and smaller container. However, a Betta fish spawn, on average, contains few hundreds of fries. Hence, to fully utilize available spaces and giving the Betta fish the optimum growing environment, what is the minimum water volume or container size that can achieve this? Our observation is most breeders will use several cost saving ways to jar individual male Betta fish. These consists of using recycle mineral water bottle, thin glass alcohol bottle, or drinking plastic bags.

Material and Methods
This is a randomized design experiment of 5 water treatments and 15 replicates. First, one-month old solid-red male Siamese fighting fishes were purchased and individually acclimatized in cylindrical plastic breakers (7.5cm diameter x 12.5cm height) of water volume of 250mL for 2 weeks (not sure why?). Then, 15 fishes (n = 15) of similar size (0.97 ± 0.01 g initial body weight)were evenly and individually distributed into 5 water volumes of 100, 150, 200, 250, and 300 mL glass aquaria (3.5cm width x 8cm length x 20cm height).

Breeding conditions for 8 weeks or 2 months as follows:
(1) Commercial floating pellets (10% moisture,  46% crude protein, 6% crude lipid, 5% crude,
fiber, and 12% crude ash).
(2) Feeding done twice daily (08:00h and 17:00h) at 2% of body weight.
(3) Photoperiod of 12h (light) : 12h (dark)
(4) Uneaten excess diet were siphoned after 30 minutes after feeding.
(5) 80% water changes with dechlorinated stock water within 3 consecutive days.

Since it's too long and quite complicated (I don't really understand it), I skipped the part on what measurements and tools used.

Results
Only the results for water quality and overall growth were discussed here.

Since leftover food were siphoned, the only contributing factor to water quality is the ammonia level due to excreted water by the fish. The lower the water volume, the higher concentration of ammonia level and lower pH level as shown in table below for water volume of 100mL.


Large water volume (300 mL) will lead to bigger fish growth (standard length) and at the same time, allows more space for increase movement (like bubble nest making) within the container, and thus, low weight gain.


Discussion
How big is 150mL? The video below will give you some idea. Should you use this minimum water volume for optimum growth? Depends. If you have large quantity of fishes, limited spaces, and plenty of time for water changes, then this should be the right option. If not, use the largest water volume possible so less than frequent water changes. When breeding and rearing Betta fishes, water changes is the only task that consumes most of your time.



Further Questions
(1) Will plastic bottle instead of glass aquaria have any significant effects on the experiment?
(2) When do we start to jar the male Betta fish? Is it 1.5 month of age when it starts to show aggression behaviour or when it reaches certain size of 2.5cm?
(3) Will there any significant changes if the water were treated with Indian Almond leaves?
(4) Is there any significant impact to the result if these fishes were fed with live food sources?
(5) Large water volume means less frequent water change. Is there any impacts on frequency of water change to the result?

Research Paper to Read: (2010) Growth and Survival of Siamese Fighting Fish, Betta Splendens, Larvae at Low Salinity and With Different Diets

Source: Research Gate.

Takeaways
(1) Combination of natural live foods (Chlorella sp., Rotifers, and Artemia nauplii) ensures good growth rate.
(2) Salinity of 5 ppt using non-iodized salt prevents the Piscinoodinium sp. parasite which is the causative agent of velvet rust disease.

Why this paper?
Betta fish (B. splendens) is one of the most popular ornamental fish and it's known to be easily breed. While there are numerous information (websites, books, and videos), most of these information are experiences gained through casual observation rather than scientific research. Two questions were raised during our breeding projects, how can we accelerate the growth and increase the survival rate of our Betta fish larvae (still have yolk-sac and unable to feed themselves) and later as fries (free swimming and can feed themselves)? This paper was written to answer both questions by investigating the best nutrients for the Betta larvae and fries for the first 15 days.

Materials and Methods
The larvaes and fry were the results of a pair of sexually mature (not sure how many months) B. splendens (not sure which species). The pair was fed twice daily (anytime) with flake food and live brine shrimp. Larvae were jararred at 3rd day into 18 round-bottom glass flasks (2L) where each flask contained 10 larvae. These were duplicated into 3 sets as follows:

(1) Treatment: Natural, Salinity: 0 ppt
(2) Treatment: Natural, Salinity: 5 ppt
(3) Treatment: AD + LA, Salinity: 0 ppt
(4) Treatment: AD + LA, Salinity: 5 ppt
(5) Treatment: SDLA + AD, Salinity: 0 ppt
(6) Treatment: SDLA + AD, Salinity: 5 ppt

Culture condition of the larvae as follows:

(1) Salinity was obtained by adding non-iodized cooking salt (aquarium salt should works as well) in portion of 5g/L in distilled water (all minerals were removed).
(2) Temperature set to 26C. (How do they maintain the temperature constantly?)
(3) Photoperiod, 12h light : 12h dark.
(4) 80% water changes on daily basis.

Below is the exact daily rations grouped into three stages of the larvae or fries lifecycle of 15 days. Larvae were fed four-times per day in a 4 hours intervals (0800, 1200, 1600, and 2000h).


Details of the diet with photos (from Wikipedia) as follows:

(1) Freshwater microalgae Chlorella sp.


(2) Rotifers (Brachionus rotundiformis, B. plicatilis "S type").


(3) Artemia nauplii (Brine Shrimp).


(4) Semi-purified microbound formulated diet (particle size 250–450 μm) with ingredients of (37.4% lipids, 46.2% crude protein and 5.6% ash)

Results
As the table below have shown, natural diet yielded the best survival rate and second in growth rate. The total average length of the fries is more precise to the observed and non scientific measurements of the Betta Growth Table.


Discussions
Why natural live food diet compare to formulated diet gave the optimum survival rate? Betta larvae or fries naturally eat moving living organisms instead of lifeless static food pellets. Furthermore, 100% survival rate was achieved with natural diet and non-iodined salt (5ppt salinity), which prevent the Piscinoodinium sp. parasite which is the causative agent of velvet rust disease as shown in figure below.


This is another photo (source: Wikipedia) showing the actual infection of the parasit.


I'm not sure why the diet of LA + AD with salinity cultured the largest growth length. Unfortunately, this was not discussed in the paper or did I miss or misunderstood it?

Further Questions
(1) When is the sexually mature age for both Betta male or female fish?
(2) How does the frequency of daily feeding (2, 3, or 4 times) influences the larvae and fries growth?
(3) How to calculate the salinity of 5ppt corresponds to the container size?
(4) How does photoperiod influence the growth, survival, or reproduction?
(5) How many percent of daily water changes needed?
(6) Why we need to perform daily water changes?
(7) Does distilled water essential for reproduction, growth, and survival of larvae or fries?
(8) Does the percentage of protein in formulated diet influences the growth and health?
(9) What is the range of salinity level for breeding Betta?

Betta Fish Growth Table

When breeding Betta fish, how do we know that the Betta fry is growing at the right rate? In the Interweb, most web sites will point to this growth chart of the Wayne's Betta pages. However, the measurement used in the page was not in metric system and it's always hard for us. Hence, we used the information from the page and converted it to metric system.

Note that this growth rate is based on normal Betta fish (Betta Splendens) and may not be suitable for Giant Betta which have different growth rate than normal Betta. Also we've extrapolated the growth rate for week 12.