Triploid Tilapia

Triploid fish are those which are sterile with three sets of chromosomes and as such will never be able to reproduce. So why would we want these sterile fish and how do we get them?

The use of hormones and antibiotics in food has skyrocketed. Not only does this have a cumulative effect on humans as we eat the meat  but also on marine life as it is eliminated and flushed out of our system into the sewers and eventually ending up in the world's oceans. We of course eat the seafood and have another dose of hormones and unwanted chemical cocktails by doing so.

So what's the answer? It could be triploid fish as this is already being seen in trout and other fish as a viable method of population control in by the US. I feel our role as  farmers is not to add to this problem but to try and eliminate  hormones from the cycle of tilapia farming if possible.

Although the treatment of hormones with 17 alpha-methyltestosterone is commonly used here in Brazil there are alternatives.  The use of cold and/or heat shock and  pressure treatment on fertilized eggs can leave the fish sterile.  This is achieved by applying  the  pressure, heat and then cold to the eggs shortly after they have been fertilized. The amount of pressure, and time held during the  heating  and chilling period are crucial to get the triploid tilapia. Too much of any of those processes and the eggs will die , not enough and it is likely to be ineffectual.

Beside saving hormones from entering the food chain, producing triploid fish is safer for the environment, as tilapia if they escape into rivers and lakes, can be an invasive species. Their rapid breeding can soon get out of hand and cause problems in many bodies of water.

It is down to tilapia farmers  to seek out alternatives and find   breeders who  are not  using hormones as a method of sex reversal.

Selling your tilapia

This is something you should think about before buying your fish. Who are you going to sell the tilapia to? There are several different options and today I would like to discuss some of these with you.

Here on our farm we use combination of these.

The first option is selling them yourself to individuals. Basically people come to you and want to buy a few fish, sometimes just one for dinner. Although both of you are cutting out the middleman and you can get a higher price for each fish, this is hassle. Catching one or two fish at a time is time consuming and as they say, “time is money”. This is still a viable option and often the other person may offer to help you. Be warned, they will be pickier than if they bought it from a store.

Another option is selling to a store. This is something we do on a weekly basis. We sell to a few corner shops. They usually require the fish for the weekend and like them to arrive Thursday or Friday. On average we sell between 25-40 kilos a week per shop. There are several small shops nearby and most of these sell fish. If this is something you plan to do, you will need a suitable vehicle for delivering these, especially if you deliver to more than one store. Although you will be quick in each store you go to, the fish should be kept cold or as cool as possible. Use large Styrofoam boxes with ice to keep the fish from going off.

The third option is selling to a middle man but smaller quantities. This too is something we do on a weekly basis. Our weekly local buyer, arrives early on a Saturday morning. We get the fish out of the lake, weighed and he is on his way. Because we try and support our local community, if he can't pay us upfront it isn't a problem, he sells the fish and then returns with the cash less his commission of course.

The last option we have used is selling to a large buyer. He sets a date, arrives with a truck loaded with ice and boxes. He also provides his team of men to prepare the fish. His men get the fish out of the lake, clean them, weigh them and then we are paid. This is a long day for everyone concerned but it means you are selling the bulk of your fish. The larger ones of course command the highest price per kilo. Our buyer paid more for anything over 800grams. The next size the pay was less and then the smallest ones less than 500 grams was less still.

Something which we haven't done is sell to a company for export to the USA. This, although profitable, isn't something we were interested in doing as all our fish were various sizes. Locally there was a tilapia farmer who looked into this and by the time he calculated the cost of the machinery he would need, and the fact that their restrictions were so tight, he too decided to pass.

These are just some of the options for selling tilapia, there are of course more and in future posts, we will be looking at even more.  

Killer Tilapia: Fact or Fiction

Sometimes you don't even want to read or listen to the news because there will be an attention grabbing headline that will make people change their eating habits, learn what is going to kill them or at least provide them with something to talk about over the water cooler at work.

The truth is most people read a headline, maybe scan the page and suddenly they know it all.

There has been a lot of mudslinging with regards to tilapia and one "expert" even suggested it was worse than bacon! Let me tell you, I eat tilapia and I also eat bacon. I suspect so does the journalist who wrote the article. They don't care about facts, they just want you to click on their page.

The world has gone crazy with regards to food. Tell me one food which hasn't been attacked and vilified, I don't think you can.

You can't eat the fruit and veg because they are genetically modified. Eggs the risk of salmonella, ocean caught fish have plastic in them.

So what are we left with All-bran and a eco- friendly vitamin pill on our plate?

Nope not for me. I plan to eat as I always have with a well balanced diet. Everything in moderation and choosing from a wide variety of meats, fish, fruits, and vegetables.

It has been stated in the media that tilapia isn't good for you for several reasons.

• The commercial feed isn't healthy: Of course there are fish farmers who use a lesser quality of fish food. We use half fish food/ half duckweed. The fish food does contain genetically modified soy products but check your manufactures ingredient list. Remember fish is a good source of low fat protein. The beef and chicken are also fed on GM foods, unless you go to a specialist retailer who sells organic meats. The fish food will have protein which may be from chicken which has been retrieved by use of high pressure hoses. It is claimed that chicken excrement may also find its way into the mixture. I believe that is very possible. Here though I would also like to point to the fact that many foods we already consume are made from this 'goo or pink slime ' as it has been called, which is extracted this way. For example hot dogs lesser quality foods are using this. 

• The use of antibiotics: Here on our farm, we have never used antibiotics. We know of some tilapia farmers who have though. This greatly increases the cost of rearing fish and if possible should be avoided. Keep your water clean, and reduce the numbers of fish to keep the growing environment healthy. Commercial farmers walk a tightrope between profit and loss. The general public never see this, they only want to hear the dirt about the farmers.

• Pesticides in water: In some areas this could be a problem. Have your water tested if you are in an area where intensive agricultural farming or animal rearing is occurring. We don't have this problem where I live in Brazil and as a result our fish are stronger and healthier. If your water is contaminated with pesticides, calculate the cost of digging a deeper well after speaking to a someone from your water board. If you are reliant river runoff, see if you can determine where the pesticides originated from. If this has affected your farm adversely you could be able to file a complaint against them and may be in line for compensation. The legal road is a long one to take and is often hellishly expensive.

• Farmed vs. wild caught: I hate this comparison because it immediately conjures up the wrong image. You have the image that some weathered and smiling fisherman  using a fishing pole is catching a salmon, just for you to enjoy. Wake up and smell the coffee! Your “wild caught salmon” is depleting the ocean's resources and is probably caught by a net which when snagged, is cut free and left. This then creates an unseen barrier for dolphins, whales and others.  Plus have you not read about all the garbage in the oceans? It is thought that ¼ of the fish caught off the Californian coast have consumed plastic. This is in the form of micro beads and other other types of plastic such as bags. California has now, thankfully  passed a bill  preventing micro beads from being used in cosmetics and other toiletries such as toothpastes. My point is, don't think that farmed fish is something to avoid. Weigh up the pros and cons before buying fish.

•  Tilapia and inflammation: It has also been claimed that tilapia can cause problems for people with asthma, heart problems, and arthritis. This is due to the ratio of Omega 3 and Omega 6 in farm fed tilapia. If you suffer from any of these conditions, consult your doctor and explain your concerns. 

These are the main reasons why people have concerns over eating tilapia. For most people, it is a low cost food which can be enjoyed in so many different ways. The fact that kids are eating something other than tuna, and one which parents are happy to prepare will still keep tilapia at the forefront of everyone's weekly menu for the foreseeable future.

Is tilapia farming right for you?

The decision to become a tilapia farmer isn't one to be taken lightly. It is easy to think of fish as something other than livestock but livestock they are. You have to be committed, day in and day out until they are off to market or on your dinner plate.

With other animals there is a constant reminder as you see them on your farm or homestead. Because fish aren't usually seen until you are feeding them, it can be easy to think, “oh, I will feed them tomorrow.”

If you wouldn't treat you dog/cat like that, then don't treat your fish like that. 

There is an exception to this and that is delayed feeding which I have written about previously.

So back to the original question, is tilapia farming for you. You have to ask yourself some questions.

• How many do you plan to raise. Is this for your own consumption or to sell?
• Have you calculated how much it may cost you to feed the until they are ready? (use the chart)
• How are you going to remove the build up of excrement from  the water?
• Do you have measures in place to heat or cool the water if need be?
• What is your intended time frame?
• Where are you going to keep them?
• Who is going to be responsible for the feeding and buying of food?
• Who will be checking the water quality.
• How will you harvest them.
• If you plan to sell, who will buy them?

All of these need to be taken into consideration before you put your money on the line to purchase your fish. You might have the goal but you need to do some prep work first.

Getting these straight from the outset will save you headaches down the road. 

 

Selecting and Using a Net

If your tilapia are free swimming in a lake or pond, netting will be the quickest option to catch them. You can of course use a fishing pole and reel if you are only planning to feed one and you feel lucky.

The size of net you will need will be dependent on the area you need to cover and the depth of your water and the size of the fish you are wanting to catch. 

The method we used was shown to us by locals here in Brazil They encircle the area, kicking the shallows to heard the fish to deeper water. They in essence corralling  the fish. The fish begin to panic, and when they swim away from you, they get caught in the net where they will stay until you remove them. The net should not be tight otherwise instead of the fish swimming into it, they bounce off as though it were a trampoline. 

The gauge of net has to be strong enough to catch the bigger fish. The spaces in the net or the openings need to be the correct size in order to catch them at the gills. You are not wanting to scoop the fish out, you are wanting them to get caught or embedded in the net. 

It is a good idea to have a variety of sizes of nets. We have about 5 different ones.

This will allow you to catch the big fish, and the others can stay and grow. 

There will of course be different sized fish caught in your net, but you can make the judgement call to keep them out or return them to the water. 

The easiest way to remove the fish is to put your thumb into the mouth and your index finger in through the gills. These are forming a ring. If you keep this secure, your fish won't be able to move. Use your other hand to pull the net off the tilapia. You will want to pull the net towards the tail otherwise it will get caught on the fins and scales. 

You may find that the tilapia has twisted itself in the net. When they are caught, they will often thrash about and become so tangled we have had no choice but to cut them free and repair the net afterwards.

Depending on the depth of the water you could pull them closer to the shore in order to remove them. This makes it much easier on you.  

One thing I would definitely suggest is wearing gloves! The mouth of the tilapia is serrated and removing one or two fish isn't a problem but after that the skin, which is soft from being in water,  will become very sore and red.

Which type of predators

The predators can be other fish or birds.

When we arrived at our home, our lake already was stocked with fish, some of these were predators which kept a balance. These included peacock bass, or as they call it here tocanare and also triara. Before we decided to start tilapia farming we use to catch the triara by using a piece of styrofoam with a hook and line attached. To this we would put a small fish as bait. We tossed these into the lake in the evening and in the morning, we had caught a triara. 

The birds can be problematic to control if you find they are taking your larger fish. Obviously those you don't want them to take and giant egrets will take amazingly large fish.

Some of the birds could be:

Cormorants

Egrets

Herons

kingfishers

The cormorant is a diving bird which will be on the surface of the water and dive down for fish. These birds are notorious as they can decimate a lake of fish. We have only seen one here on our lake and he was encourage to leave.

The egret will wade into the water and stab at the fish. There are many different types and sizes of egrets. We have seen the smaller snowy egret work as a team herding small shoals of fish into the water's edge where they are easily plucked out. The giant egret prefers to work alone and in fact will often chase off others who want to encroach on its feeding ground.

The heron will wait at the shore for fish to come within striking distance. We have seen them using bait, namely fish pellets to lure a fish to the shore.

The last is the kingfisher. Here we have three different sized kingfishers and all hover above the water, spot their target, pull their wings back and with the accuracy of a missile plummet into the water, normally coming out with a fish. 

Depending on your circumstances and the size of your fish, you may wish to encourage or discourage the birds. If you have an over population problem then these will be a help. If your fish have just arrived and are small, then they are easily preyed upon and should be discouraged with nets, noise or other birds such as geese. We found when we had geese they were aggressive against other waterfowl.

Deformities in Tilapia

Deformities in tilapia

In fish farming it's important to think about the end user. If your fish are going to be fileted before the consumer sees them there is likely to be no problem. However if you are selling to restaurants which serve whole fish, you need to be producing not only heavy fish but also attractive ones. The consumer, doesn't want to know about what goes on at a fish farm just as they don't want to know where their beef, pork, chicken or lamb comes from.

The truth is in fish farming you get fish with deformities. It isn't that there is anything wrong with the quality but visually this could be a problem for the unsuspecting public.

So what causes this to happen?

When you buy multiple fish from a breeder it is likely you will have some with deformities due to breeding conditions, such as over crowding or even injuries which didn't heal correctly.

We noticed fish which had eyes missing. This could have happened due to the intensive breeding conditions.

We also had some which appeared to be a birth defect. This was evident in the lack of a dorsal fin. Perhaps, given a high volume of fish, there will always be this anomaly. If you are new to fish farming or farming in general, this can be quite disturbing to see. I can't say this impeded the development of these fish as they ate and swam as well as the others.

For us it didn't affect the value of our fish as we sold them by the kilo. If these were sold to restaurants, it could be that they would take only fish without any obvious abnormalities if they were to be served to their clients as whole fish.

Another thing I would like to mention here is specific to keeping fish in cages. The fish although they know they are caged, will swim into the sides. This leads to red mouths or contusions. This too doesn't affect resale value if selling by the kilo but yet again, doesn't look correct when eating at a restaurant.