Catfish,of Course!

[frikkiedeboer]

Here is some info I found on the net regarding catfish farming. Tried and tested in Thailand myself-_it works. they speak of the "african catfish" or "clarias gariepinus"._There is no signifigant difference between clarias gariepinus and c.macrocephalus (a hybrid of the two is what you are buying from thai hatcheries -this is your "beeg ooie")

The hybrid exists because of the poor growth-rate, low fecundity and resulting poor performance of the local species, (which means tat there are some thais who know something about rearing catfish!).

The thais will tell you that the local species tastes better,- that the flesh of the lakseer/pladouk-yak is white and that of the ooei is yellow,-that the thai species is a green colour,-that the lakseer has a big head and a long thin body,and that the lakseer is cannabalistic etc etc

This is all bull:

Reality is that

1: very few thais can tell the difference between the two species- cut the head off two of different species and ask even the "expert" to tell the difference and I will lay money on it he will not be able to!

2: the flesh of both species is a yellow colour and can vary according to what they were fwd on

3.the flavour of the fish depends on what they were fed upon

4. the colour of the fish varies according to their environment-they can and do react to environmental conditions by changing colour and this can take place within a matter of hours-

5 all clarias catfish are cannibalistic. The only way to limit this is adequate feeding of the correct type of feed and repeated sorting and culling of fingerlings-note: THAI HATCHERIES DO NOT CULL,and non performing fish,plus fingerlings of different ages are mixed in the basket you buy,so you will buy fish of roughly the same size, but they will not grow out at the same rate. (I found this to be the biggest problem limiting profitability,next to the cost of feed in Thailand)

5. the lakseer (African catfish) grows faster than the thai hybrid,and if it ends up long and thin it is because of the thai habit of underfeeding. Fed properly they attain the shape and size the thais favour,only faster!

Here follows some more excerpts from the same site, regarding growout techniques and nutritional requirements, including some cheap but proven feed recipes::

"The potential of ultra-high density farming has since been investigated in South Africa, using C. gariepinus and the C. gariepinus (female) x H. longifilis (male) hybrid -longifilus is the "vundu" catfish common to Zimbabwe and zambia-(frikkie)

. Catfish have been successfully reared at densities of 850 kg.m^-3 in a fully recirculating system. The hybrid fish were grown at different densities in 1 m³ concrete tanks with one water exchange per hour to establish the density at which yield would be optimised. Optimal yield (expressed as weight gain over time less starting weight) was obtained at a density of 415 kg/m³. Under conditions of optimum density the fish were grown from 30 g to 850 g in 8-9 months at an average FCR of 1.17. Theoretically this means that for a high density tank culture unit with a production surface area of 1.0 ha some 4000 tons of fish could be produced per year.

Terminal density at which yield was zero or negative could not be attained. Even at densities of 965 kg/m³ the fish were still growing, although at a reduced rate. The maximum yield that was obtained at the maximum final density of 965 kg/m³ was 881 kg.m^-3 in 4 months. -881 kg weight gain in 4 months from a 1 cubic metr tank!! -frikkie- This clearly illustrates the remarkable aquaculture potential of the African catfish.

The highly favourable FCR obtained by many workers under high density tank culture conditions (1.05 - 1.41) can probably be attributed to the feeding behaviour of the fish under crowded conditions. Under conditions of high density the catfish react faster to the presence of food and consume a meal much faster than under low density conditions. Fish in a low density tank leisurely select pellets from the floor of the tank. However, under high density conditions they typically go into a "feeding frenzy" as soon as food is detected.

Approximate minimum dietary requirements for African catfish

Feed

Percentage

Crude Protein

40%

Total lipid

11%

Digestible energy

12 kJ/g

Calcium

1.5%

Phosphorus

0.5%

At this stage the best growth rates and feed conversion ratios are achieved with a diet containing 38 - 42% crude protein and an energy level of 12 kj g^-1. The requirements of catfish for essential amino acids, essential fatty acids, vitamins and minerals have not yet been determined. For convenience, many researchers have made the assumption that vitamin and mineral requirements are similar to those the channel catfish (Ictalurus punctatus). Some recent work in Thailand on the vitamin C requirements of a hybrid between Clarias gariepinus and Clarias macrocephalus has shown that growth, FCR and survival is enhanced with a minimum vitamin C content of 42 mgL - ascorbic acid / kg or 80 mg ascorbate vitamin C - glucose /kg food. Research has also been undertaken on optimum protein:energy ration's in diets. .

Programmed least-cost formulation is a widespread technique used in the animal feed industry. It is aimed at finding the cheapest way of combining a given set of ingredients with a known nutritional composition, while at the same time satisfying the requirements of the animal concerned and obtaining maximum growth at least cost.

Programmed least-cost formulation is a widespread technique used in the animal feed industry. It is aimed at finding the cheapest way of combining a given set of ingredients with a known nutritional composition, while at the same time satisfying the requirements of the animal concerned and obtaining maximum growth at least cost."

Examples of least cost diets for Clarias gariepinus with resulting feed conversion rations (FCR) and cost efficiencies

Diet No

1

2

3

4

5

6

7

8

9

Control

Maize %

-

4.6

15.0

30.0

-

10.5

-

-

-

18.0

Wheat %

-

31.8

15.0

-

30.0

-

14.0

-

-

18.0

Cotton 0/C%

-

-

-

-

-

25.0

-

-

-

-

Soy O/C%

10.0

-

-

-

-

10.0

10.0

-

-

-

Fishmeal %

24.7

16.0

10.0

10.0

10.0

20.0

10.0

10.0

-

43.5

Poultry bpm%

10.0

10.0

-

10.0

10.0

9.0

10.0

26.0

35.2

-

Carcass meal %

10.5

27.6

50.2

39.5

31.4

-

22.7

-

-

10.0

Lucern meal %

30.0

-

-

-

-

-

-

-

-

-

Tomato waste %

-

-

-

-

9.7

8.0

20.0

50.1

50.0

-

Fish acid oil %

6.8

-

-

2.5

0.9

7.5

3.3

5.9

6.8

2.5

Molasses powder %

8.0

10.0

9.8

8.0

8.0

10.0

10.0

8.0

8.0

8.0

Crude protein %

38.0

38.0

38.0

38.0

38.0

38.0

38.0

38.0

38.0

38.0

Total lipid %

13.5

8.0

8.1

11.7

9.8

14.2

12.5

19.8

21.6

9.0

DE (kJ/g)*

12.0

12.0

12.0

12.0

12.0

12.0

12.0

12.0

12.0

12.0

Price/ton ®**

655.0

586.0

580.0

569.0

543.0

603.0

531.0

415.0

376.0

722.0

FCR

1.05

1.19

1.16

1.25

1.19

1.13

1.12

1.46

1.54

0.98

sorry, the table doesnt paste as it was copied, but if you print it and stick the columns next to one another it will make sense. -note that the control group in the tank returned an fcr of 0.98:1!

the trick seems to be to try to replace the expensive fishmeal with another protien source-note that soya will have to be ultra-heat-treated. i do not know if this affects the digestability of the stuff but can tell you from experience that the stuff goes off and turned mouldy very quickly -possibly this is the reason that all the formulations specify uht soya.

if you can get hold of the lees from a beer brewery,it is an excellent source of protien,too-so check it out-i do not know if the thais discard it or use it to produce anything else but it could be worth checking out

I hope that the aspirant catfish feed manufacturers out ther could do something with this. Also found some info on feeds using cattle blood as the protein source but I hesitate to quote this as I do not know the protein content and don't want to make a <deleted> of myself again by quoting them at 98% as they did (true!-swear it upon my mother-in-law"s life!).

I made some of this stuff and it seemed to work but didn't have time to do a proper study, and had no means to test it properly, but if you check out the feed from"acco" feeds in Thailand it seems to be made from blood,too.

Good luck

frikkie

Edited April 15, 2007 by frikkiedeboer

[Somtham]

edit...if you can get hold of the lees from a beer brewery...edit

What are "lees"? Also, can you post the website where you got the feed table from?

rgds

[frikkiedeboer]

edit...if you can get hold of the lees from a beer brewery...edit

What are "lees"? Also, can you post the website where you got the feed table from?

rgds

lees ( i am not sure if i got the spelling right- been twenty years or so since i last brewed my own) is the leftover yeast after the brewing process. if a lager is brewed ,the yeast would be bottom-fermenting, and an ale or wine would ferment on top. in south africa this stuff is boiled up and reduced to form a sticky ,high protien yeast extract and sold as a sandwich spread! it is well worth checking this out as it really is a very good protien source and could be very cheap. sorry that table didnt work and was so confusing. the luscern one was of particular interest since there was a rescent posting by someone who wanted to grow it.i got those feed formulations,plus a lot of other info over the years off rhodes university's site- found it on google search -just key in "high density catfish farming" and you will get there.page through the whole thing-it is fascinating,and packed with very valuable information-even if they do assume you have an icthyology degree already-(not enough detail for someone who hasnt studied it ) check out the commentary on the zambian operation they mention- those guys used brewery waste,tho it was what we call in south africa: "kaffir beer" and is fermented on the millet they use instead of barley ,without straining after the mashing process ,so they would have less protien and more carbohydrate,i suppose, than a farang lees would

please get that bloody feed working and test and post your findings so we can all start making a real profit

regards

frikkie

[ozzydom]

Yep, its the residue grain yeast etc that is strained off at the end of brewing,you see truck loads of it down around Khon Khan ,they feed itr to pigs among other uses, also used as compost. If you get behind a truck of it you wont forget the smell.

[Khonwan]

I tried to buy 'kaag beer' (as the Thais call it - beer waste/residue) several years ago for my cattle feed. Tried Carlsberg and a mini-brewery in Bkk. Couldn't buy it direct as it was all under contract.

[btate]

In trying to decipher the original chart I noted one 'ingredient' that intrigued me... tomatoes.

So I went to find what that was about and found this...

Hope it helps.

Bt

EDIT: Prices listed at the bottom of the chart are in Rand and prolly out of date.

Edited April 16, 2007 by btate