What do you need to breed your seahorses to enable them to be very productive in reproduction?

For breeding, seahorses do require some special treatment, should you want to have loads of cute little baby seahorses!

1. Nutrition is extremely important! Ensure your females are producing good-quality eggs by feeding her high-energy food, such as frozen (or live) Mysid shrimp.

2. Tank depth! At least 50 cm is recommended for sub-adult seahorses to breed, and 1-m for full-grown adults.

3. Very good water quality! Ensure the ammonia and nitrite are low, your temperature is stable around 18-20 oC, and salinity is between 20-35 ppt.

4. A small tank for your babies, as well as live baby brine shrimp.

5. It is always good to keep seahorses in their own aquarium. Never put seahorses in an aquarium with aggressive and fast feeders as seahorses are gentle feeders, which will be edged out in food rivalry. 

Gestation period

Sea horse reproduction usually occurs from May to August. There is something known as the gestation period for humans of around 9 months. Well, does the same apply for the seahorse too? YES! :) They too have a gestation period. However, it is only for 40 to 50 days. For these days, the male is the SOLE caretaker of the eggs, present in the tightly sealed sack.The eggs inside the sack attach themselves to the male with umbilical cords. He goes through everything a regular female goes through when they are pregnant. The male may be in a state of labour for hours until the young are ready to emerge from the pouch. The babies emerge as miniature sea horses and make their way to the surface of the ocean.

Actually, the duration of pregnancy relies on temperature of water.

Parts of the reproductive system of a seahorse! :)

 

A photo showing the different parts of the seahorse :)

Just like humans, the seahorse has many different parts in their body, having tubular testes and a duct system that merges with the urinary bladder at the cloaca. However, seahorses do not posssess an external copulatory organ! They have the anal fin instead.

Anyway, which are the ones that are classified under the reproductive system?

They are the:

- Tail

- Mesenteries (extend along body cavity just in front of the kidneys, in body of the seahorse)

- Anal fin
- Male brood pouch (only for male seahorses)

What part do they play in the reproductive system then? :)

First, the tail is used in greeting rituals and to hold onto a partner during mating.

Next, the mesenteries suspend the reproductive organs of the seahorses- testes of males and ovaries of females, where they are paired structures.

Moreover, the anal fin is situated above the opening of the brood pouch and covers it, where it then has connection with reproductive activity. It does this by directing the sperm released by the urogenital duct towards the mature eggs as they travel from the female to the male's brood pouch.

Last, the male brood pouch is located on the front of the tail. The pouch opening is positioned just under the anal fin and during mating, it is opened to allow the female to deposit eggs. The brood pouch lining provides nourishment (nutrients and oxygen) to the developing egg and removes all harmful waste. During the development of the young, the salinity of the pouch increases so that they will be adapted to seawater! Though it does not play a direct role in fertilisation, it does indeed ensure that the young are in safe hands but thus considered a secondary sex characteristic. The size of seahorse broods is much smaller than that of most fishes.

Hope you have benefited from this insight on the reproductive parts of seahorses! :D

A closer look! :)

Is there a physical difference between the male and female seahorses? :)

As seen from the above illustration, the physical similarities between the male and female are striking! The only discernible difference scientists have been able to find is in the abdominal area where the female is rough and angular.  The male is smooth and the reproductive pouch is visible. 

How a male seahorse gives birth!

Since we now know what happens during courtship, let us take it a step further and observe the types of symptoms or changes occuring during birth! :) Here is an interesting video which clearly highlights how a male seahorse gives birth! So, sit back, relax and enjoy!



At the time of birth, the brooding pouch extends and the male undergoes a period of muscular contractions where he bends forward and backward.  After a short period of time, usually about ten minutes or so, the baby seahorses will be released into the water, looking like miniature versions of their parents, at which point they are basically on their own.  Infant mortality in the seahorse world is extremely high with very few living long enough to mature and mate on their own, contributing to their growing risk for extinction.  Those that do survive can expect a life span between four and six years.

Seahorses!

Reproduction in seahorses:

SEAHORSES are part of the family syngnathidae (‘sing-nath-i-dee), which means, “fused jaw”. All seahorses, nearly 50 species, belong to the genus Hippocampus. As in most organisms, the reproductive system of the seahorse consists of tubular testis and duct system that do not possess an external copulatory organ. Males do however, employ an anal fin, which is situated just above the opening of the pouch and helps to direct the ovulated eggs into the pouch. The anal fin also directs sperm released by the urogenital duct towards the mature eggs as they travel from the female to the males brood pouch. Because the brood pouch plays no direct role in fertilization, as it is anatomically separated from the reproduction system, the pouch is considered a secondary sex characteristic.

Birth

     The males are pregnant for several weeks before giving birth to their brood (Vincent, et. al 1992).  When they prepare to give birth, the pouch extends to an almost spherical shape.  The male also undergoes muscular contortions - a forward and a backward bend - that last for about ten minutes.  then in an explosive action the brood leaves the pouch.  After the last young sea horse has left, the pouch returns to its normal position, which usually takes about an hour (Breder 1940).  Males are ready to re-mate within a few hours of giving birth (Vincent, et. al 1992).

Seahorse Mating Dance!

Following up on the previous post, we wonder why the seahorses actually have to engage in this mating dance! :) Well, here is a brief description of what happens during a seahorse mating dance.

Before seahorses begin mating, they first have to do a mating dance! As shown in the previous video, they swim together and link their tails.

Seahorses linking their tails!

Here's an explanation of the seahorse "courtship dance"!


Before breeding, seahorses actually put a lot of effort into the courtship, and court each other for several days. Why? It is believed that the dance synchronizes their movement patterns so that the male can receive the eggs when the female is ready to deposit them into his pouch.

Male seahorse swelling up! :)

During the courtship dance, they may change color (by lightening or darkening their skin), or swim side-by-side, tails entwined, or grip the same blade of sea grass with their tail and whirl around depending on the seahorse. The female aligns a long tube called an ovipositor with the males pouch and this is known as the pre-dawn dance.

Seahorses have only one mate and thus, during the mating period they engage in a lengthy courtship. The actual courtship dance lasts about eight hours.

The male pumps water through the egg pouch on his trunk which then expands and opens and allows the female to deposit her eggs. These eggs range in numbers, from dozens to thousands. She does this by inserting her oviduct into the male's brooding pouch.

By doing this for several times for short intervals, she avoids exhaustion. During the breaks, the male contorts himself to try to get the eggs in place in his brood pouch. After the last egg is safely inside the male's brood pouch, it seals up and he stretches and twists his body to settle the eggs comfortably in the pouch. Finally, the male moves away and attaches himself by his tail to a nearby plant while the female moves away too and waits for her oviduct to recede. It usually recedes within a few hours. 

 The eggs are left there until they hatch. Afterward, the female's body shrinks and slims, while, ironically, the male's body swells. At last, they will let go of any anchors and snout-to-snout, drift upward out of the seagrass, often spiraling as they rise.

An interesting video on mating! (Mating dance)

This is a short clip of two seahorses performing a mating dance!
Well then, why do these seahorses need to perform this? :)  What are the benefits of this? Does it make them more attracted to each other? We shall find out more in the next post!

Introduction to what the blog is about! :)

Basically,  this blog is for a biology project and the topic we have chosen is the reproductive system of seahorses. It mainly provides information and loads of pictures or videos to illustrate our points, etc. We chose the seahorse as we were intrigued by the fact that males were the ones that kept the young instead of the usual, where females were the one instead. We hope this would give others a deeper understanding of their 'queer' system! :)