Shaduz Fish Consult

04/02/2020

THE SPECIES OF CATFISH AND THEIR GEOGRAPHICAL DISTRIBUTION

In nature there are over 3000 species of catfish and you can find them on almost every continent. The size of catfish species can vary from less than 1cm to over 2m long. What all catfish have in common is the absence of scales and the presence of barbels, although they differ in number and size. Some of the catfish species are cultured and are important food fish for human beings, for example the African sharptooth catfish(Clarias gariepinus),the European catfish(Silurus glanis) and the American catfish(Ictalurus punctatus). Other catfish species are very beautiful,colourful and greatly appreciated as ornamental fish in aquaria and ponds.

The African sharptooth catfish belong to the family of Claridae and has its geographical distribution over the whole continent of Africa. Because of their importance as food fish, African sharptooth catfish are exported to Asia as well as to South America and Europe where they are cultured and grown for human consumption. Their natural habitat are tropical swamps,lakes and rivers,preferably slow-moving water. If the water body dries up,they can even survive in the mud until the next rainy season.

*BIOLOGICAL DESCRIPTION*

Skin
African sharptooth catfish have a scaleless slimy skin,which is darkly pigmented,brown and black on the dorsal and lateral(top and side) parts of the body. The skin over the abdomen(belly) is lighter coloured grey to white. Depending on the colour of the water,the pigmentation changes. Catfish tend to adapt to the colour of the water,in order to be less visible. The slime of catfish acts as a defense mechanism against parasites and bacteria. Always be careful not to damage or reduce the slime of the skin,otherwise you will certainly get problems which can cause fish mortality.
_

_

27/01/2020

*BROOD STOCK SELECTION(ADVISE FOR BREEDERS)*

It all starts with acquiring good quality brood stocks. Unfortunately, it is difficult to buy them from other farms. The best way forward is to select catfish from good farmers who sell fish for consumption and/or select them from your own fish which you grow for consumption.
The first selection takes place for the general performance of a group of fish in a particular pond. Have they done fairly well,in terms of little disease problems, low mortality and excellent growth? Then you should start to select the biggest females amd males from this group, when the time for harvesting and selling the fish from this pond has arrived. Also look out for fish in good condition without deformities. If the fish weigh between 1 and 2 kg,the females already have their bellies full of eggs. This is considered a bad sign. Females less than nine months old,should not yet be mature. Therefore, you should select female catfish for late maturation. As long as the females are not yet mature, they convert all the feed they consume to somatic growth, which means more meat. This is exactly what a grow-out farmer wants. The moment a female matures,the majority of the feed will be used for producing eggs. Some farmers ask for small brood stock because it is cheap,but I believe fish for brood stock should weigh at least 2.5kg and more and be at least one year old.
In order to avoid inbreeding, never use females and males from the same batch of fish.
Most likely, this fish population will consist of full siblings, which will inbreed when they are used for brood stock.
When you want to start your own hatchery,start with fixing your brood stock facility before building the actual hatchery. Give your fish time to settle in and grow and wean them in a good condition.

20/01/2020

External anatomy of catfish

The armor plates are evident in
Corydoras semiaquilus .
Most catfish are bottom feeders . In general, they are negatively buoyant, which means that they will usually sink rather than float due to a reduced gas bladder and a heavy, bony head. Catfish have a variety of body shapes, though most have a cylindrical body with a flattened ventrum to allow for benthic feeding.
A flattened head allows for digging through the substrate as well as perhaps serving as a
hydrofoil . Some have a mouth that can expand to a large size and contains no incisiform teeth; catfish generally feed through suction or gulping rather than biting and cutting prey. However, some families, notably Loricariidae and Astroblepidae , have a suckermouth that allows them to fasten themselves to objects in fast-moving water. Catfish also have a maxilla reduced to a support for barbels ; this means that they are unable to protrude their mouths as other fish such as carp .
Catfish may have up to four pairs of barbels: nasal, maxillary (on each side of mouth), and two pairs of chin barbels, even though pairs of barbels may be absent depending on the species. Catfish barbels always come as pairs. Many larger catfish also have chemoreceptors across their entire bodies, which means they "taste" anything they touch and "smell" any chemicals in the water. "In catfish, gustation plays a primary role in the orientation and location of food". Because their barbels and chemoreception are more important in detecting food, the eyes on catfish are generally small. Like other ostariophysans , they are characterized by the presence of a
Weberian apparatus . Their well-developed Weberian apparatus and reduced gas bladder allow for improved hearing as well as sound production.
Catfish do not have scales; their bodies are often naked. In some species, the mucus -covered skin is used in cutaneous respiration , where the fish breathes through its skin.
In some catfish, the skin is covered in bony plates called scutes ; some form of body armor appears in various ways within the order. In loricarioids and in the Asian genus Sisor , the armor is primarily made up of one or more rows of free dermal plates. Similar plates are found in large specimens of Lithodoras . These plates may be supported by vertebral
processes , as in scoloplacids and in Sisor, but the processes never fuse to the plates or form any external armor. By contrast, in the subfamily Doumeinae (family Amphiliidae ) and in hoplomyzontines ( Aspredinidae ), the armor is formed solely by expanded vertebral processes that form plates. Finally, the lateral armor of doradids , Sisor , and hoplomyzontines consists of hypertrophied lateral line ossicles with dorsal and ventral lamina . the channel catfish has four pairs of barbels .
All catfish, except members of Malapteruridae (electric catfish), possess a strong, hollow, bony leading spine-like ray on their dorsal and
pectoral fins . As a defense, these spines may be locked into place so that they stick outwards, which can inflict severe wounds. In numerous different catfish species, these fin rays can be used to deliver a stinging protein if the fish is irritated; as many as half of all catfish species may be venomous in this fashion, making the Siluriformes overwhelmingly the vertebrate order with the largest number of venomous species. This venom is produced by glandular cells in the epidermal tissue covering the spines. In members of the family Plotosidae , and of the genus Heteropneustes , this protein is so strong it may hospitalize humans who are unfortunate enough to receive a sting; in Plotosus lineatus , the stings can be lethal.

Juvenile catfish, like most fish, have relatively large heads, eyes and posterior median fins in comparison to larger, more mature individuals. These juveniles can be readily placed in their families, particularly those with highly derived fin or body shapes; in some cases identification of the genus is possible. As far as known for most catfish, features that are often characteristic of species such as mouth and fin positions, fin shapes, and barbel lengths show little difference between juveniles and adults. For many species, pigmentation pattern is also similar in juveniles and adults. Thus, juvenile catfishes generally resemble and develop smoothly into their adult form without distinct juvenile specializations. Exceptions to this are the ariid catfishes, where the young retain yolk sacs late into juvenile stages, and many pimelodids, which may have elongated barbels and fin filaments or coloration patterns.
Sexual dimorphism is reported in about half of all families of catfish. The modification of the a**l fin into an intromittent organ (in internal fertilizers) as well as accessory structures of the reproductive apparatus (in both internal and external fertilizers) have been described in species belonging to 11 different families.

Thanks....

17/01/2020

*Chlorine*

Chlorine is a highly toxic chemical which is used for disinfecting materials and systems at the farm. It kills all the germs 🦠. But it is used to disinfect the drinking water by chlorination. Fry are more susceptible to to chlorine than adult fish. Lethal concentrations vary from 0.01 mg/l for fry to 0.25mg/l for bigger catfish. Test kits for chlorine are rarely available in Nigeria,but they do exist.

*What does chlorine do to the fish?*

Chlorine is an oxidizer and kills every living tissue by causing necrosis. In catfish lethal levels of chlorine will cause the slime on the skin of the fish to disappear within 24 hours. The fish will certainly die. Also, chlorine attacks the respiratory system. So, the gills and the labyrinth organ will be affected too, causing breathing difficulties.
Fortunately, removing chlorine is not that difficult. Chlorine is relatively unstable in water and will vaporise from the water by itself within 24 hours, especially if you aerate it. A quick neutralization of chlorine can be carried out with sodium thiosulfate at doses of 2 to 7 parts of sodium thiosulfate for 1 part of chlorine. If you have 2 m3 water with a concentration of 0.5 mg/l chlorine, you need to neutralize the chlorine with chlorine with 2 to 7g of sodium thiosulfate.

*pH and alkalinity of water*

The pH of pure water is 7. In general,water with a pH lower than 7 is considered acidic, and water with a pH higher than 7 is considered basic. The normal range of the pH in surface water and ground water is between 6 and 8.5. This is also considered to be a good pH for fish to thrive in. The complete pH-scale ranges from 0 to 14. A pH lower than 6 and higher than 8.5 is dangerous for the well-being of fish. In both cases the slime on the skin and the gills themselves are affected. The slime on the skin actually dissolves. In addition, when the pH is high the ammonia-ammonium ratio is shifted towards the very toxic ammonia.

Alkalinity refers to the property of water to neutralize acid; it’s an expression of the buffering capacity. For fish farming the alkalinity of the water should not be less than 25mg/l equivalent calcium carbonate(CaCO3). Farming in extensive earthen ponds, creates an environment which enhances the natural production. When the water is acidic and the alkalinity is low(less than 25mg/l), the buffer capacity of the water should be enhanced. In Nigeria this is usually carried out by adding lime to the water or onto the bottom of the pond. The dosage is 300 kg per 1000 m2 of the pond.
This way algae can grow and the natural cycle of phytoplankton to zooplankton is triggered.
Catfish thrive better in a pond with an algal bloom than in a clear water environment. When the pH of the soil and the water is already above 7.5 at the end of the day, there is no need for additional liming! New ponds which just been constructed, need lime to make them fertile: 2000 kg for sandy soil and 4000 kg for clay per ha. This can be carried out in an empty pond before filling it with water. The lime also disinfects the soil and enhances mineralisation of the mud. One or two months after the ponds have been filled, you can test the total alkalinity with a test kit available in Nigeria. It should be more than 25mg/l. If the alkalinity is less than 25mg/l, you can add another 200kg of limestone/ha, and repeat this as long as necessary(source: FAO, pond conditioning through liming).

*Heavy metals such as copper,zinc,cadmium,lead*

Some heavy metals, in small quantities though, are necessity for growing fish. They are part of the essential micronutrients which are even added to the feed. But when they occur in the water, even at low concentration, they will be toxic to the fish and should be avoided by all means.
Normally in groundwater you will not have problems with heavy metals,but when you are using copper or galvanized pipes, you certainly will elevate the levels of copper,zinc and cadmium in the water. This will be devastating for the results of your hatchery. If you use river water, you will not usually have problems with these heavy metals, but when a river passes heavy industrial or urban areas,you have to be cautious. Fish can become chronically sick and get susceptible to disease or die directly from this type of pollution. Most of these pollutants damage the internal organs and eventually this will lead to mortality. Fish eaten from polluted rivers are even dangerous for human health. The natural food for river fish is polluted as well, and the fish will deposit these heavy metals in their organs and fat.

*Concrete*

Newly built concrete ponds filled with water,will elevate the pH(basic) of the water for some weeks, but after this period the pH will be adjusted to the pH of the incoming water.
So, it is advisable to leave a pond at least one or two weeks filled with water without fish in order to neutralize the effect of concrete. After two weeks it’s usually safe to stock fish in it, but flush the water first and refill.

Thank you ...

16/01/2020

Follow these simple rules to keep your farm business healthy and free from *"what if."*
It is best to prevent; solving problem is often difficult, costly...

=> Watchout for signs of challenge/risk and inject mitigating factor - spt techniques
=> Ensures staff requirements and management style - quality assurance Ctrl
=> Your level of commitment - ability to turn seed to plant - manipulate recourses
=> Understand financial inflow and exits.
=> Improving learning and performance - time management is necessary and obtain variety of extra information on the business module. This will involve the use of IT to retrieve relevant info.
*•√* Develop solid *Business Plan* (research skills, financial a**lysis, ability to work independently and solve problems)

Once this aspect is neglected, the business is likely to fail!

Thanks...

Consult Us About Us Consult Us About Us Hello there! Welcome to Sansa AgroWHO WE ARE SANSA AGRO was founded in 2017 delivering high standard quality products and better services to our clients. We have extensive experience in businesses and through assessment and audit of your enterprise, we identif...

16/01/2020

*FEEDING CATFISH*

Feeding catfish is the most important part of the job. The feed cost can be as much as 75% of the cost price of the fish. So, feeding should be carried out by the most experienced staff who have a good eye for the fish and their behavior. Only then can the amount of feed be adjusted to the appetite of the fish.

The following feeding levels can be distinguished:
*No feeding*
It’s obvious:no feeding results in no growth,but that not all. The fish will also decrease in weight with at least 1% every day. Insufficient feeding happens a lot among Nigerian fish farmers due to bad financial planning,not purchasing feed in time or lack of water.
One day without feed,results in two days without growth. It is clear that the economic results will be bad at the end of the cycle when the fish are harvested.

*Maintenance feeding level*
Just enough feed given to the fish to keep them at the same weight, is the maintenance feeding level. At this level there is no weight gain and no weight loss. This is a loss too,because the feed is wasted.

*Underfeeding*
Underfeeding happens a lot at Nigerian fish farms and is partly due to the difficulty in finding the optimum level for feeding. Some farmers are just afraid to overfeed the fish and as a result are underfeeding. Also,when the water supply is limited, farmers tend to underfeed to avoid pollution. Low availability of feed and its financial consequences can cause the farmer to start rationing the amount of feed. This is easily preventable though.
Make a financial plan for the feed you need before you stock your fingerlings,post fingerlings or juveniles. If you don’t have the financial means for the optimum feeding level,cut down the number of fish you want to grow. If the optimum feeding level is practised, this strategy provides for better economic results, despite the lower number of fish.

*Optimum or maximum feeding level*
The optimum or maximum feeding level is the level you have to obtain to maximise your profit. It is the quickest growth you can achieve with the fish you have stocked under your farming conditions. Only experienced fish farmers are able to achieve this level during the complete growth cycle.

*Overfeeding*
When you overfeed,you feed more than the fish can eat. If you use floating feed, this will be easy to see; the feed keeps floating at the surface of the water without being eaten. It will pollute the water and it is really a waste of money. Some farmers believe that, if the fish gets hungry,they will eat it later. The truth is,catfish don’t like to eat old feed floating at the surface. The taste has completely gone.
The different types of feeding level are giving in the diagram that I will post below. It also shows another parameter which is called the feed conversion rate or FCR.
_

16/01/2020

*Additional equipment and facilities*
1. Boiler to produce steam for extruding the feed or pelletizing the feed.
2. Laboratory for quality control.
3. Generator house transformer for PHCN-supply(generator up to 500 KVA).
4. Diesel tank.
5. Control panels.
6. Workshop.
7. Store for spare parts.
8. Warehouse for empty feed bags.
9. Cold store for sensitive addictives such as vitamins and minerals.
10. Administration block.
11. Canteen.
12. Boreholes(s),water storage tank and water conditioner.

16/01/2020

*IS IT ADVISABLE TO MAKE YOUR OWN FEED?*

Many fish farmers think about making their own feed. They believe it is something they can do easily alongside farming the fish. In their opinion it is also very profitable because it reduces the production costs of the fish. All this is based on assumptions and gossip from other farmers. It’s an idea born out of ignorance, because if you know all the ins and outs of feed milling,you will certainly think twice before starting a feed mill yourself.
Starting your own feed mill should only be considered if there is no alternative. Don’t be a jack of all trades and master of none!
Nowadays Nigeria has at least four professional feed millers with the professional equipment,purchased from overseas and owned by multinationals based in Europe and the USA. Their scale of production is massive(2000-4000 tons per month) and efficient. They have good connections for purchasing raw materials. They use software to change the feed formula based on the low-cost formulation without minimizing quality. Because quality control is carried out during the entire production process,the feed always has a consistent quality.
The prices for feed are very competitive,because feed millers need this scale of production in order to survive. Net profit margins are less than 10%. They employ a lot of marketers and have a wide distribution network. Before starting your own feed mill at farm level,you have to ask yourself: “Can I compete with companies like this? And,is it not better to have a good agreement with a feed mill to purchase from them instead of producing it myself.

Thank you....

15/01/2020

Smoked fishes in smoking khlin...

15/01/2020

Fingerlings ....sharp shooters

15/01/2020

A fish pond is defined as a body which has an inlet and an outlet in order to manage the pond when it comes to draining,flushing and harvesting. If a pond does not have those features,it is not a fish pond in my opinion. In any case,a fish pond is not just a hole in the ground.

Building a pond and the choice of materials depends on many factors:
1. Composition of the soil
2. Size of the land
3. Personal preference
4. Capacity of the farm
5. Financial capacity

15/01/2020

Harvesting table size fishes in pond C-A-3...