Aug 18 2017

Country report- Peru (2015)- in Spanish

A permission from the report owner has been granted to publish the report on this website

country-report-peru-2015

 

 

 

 

 

 

 

 

 

[gview file=”http://fishconsult.org/wp-content/uploads/2016/12/Country-report-Peru-2015.pdf”]

Permanent link to this article: http://fishconsult.org/?p=13765

Aug 17 2017

Organic shrimp farming in Asia (Video)

Video credit: Jimmy Lim (Aquamimicry China)

Review: Jimmy Lim and Abdel Rahman El Gamal (Founder of the channel)

The video was filmed in a shrimp farm located in Hainan (China). The video shows the preparation of the ponds before stocking of the post larvae. There is a growing interest in organic food including organic shrimp. The driving forces behind the promotion of organic shrimp are mainly food safety and farm economics especially such farms rely on natural food in feeding.

Before stocking the shrimp post larvae, the management of shrimp grow-out farm targets the development of sufficient copepods bloom using a specific type of Probiotics as well as tea seed cake and rice bran. The use of tea seed cake targets the elimination of small unwanted fish if exist without the need to apply chemical disinfectants. It is believed that rice bran whether grinded or fermented rice bran would enhance more copepod development. The probiotic is applied based on the pH of the water.

According to published protocols, the water is pumped into shrimp ponds through 300-micron mesh for filtration. The aerators shown in the video operate for 7 to 10 days before the stocking of shrimp post larvae. The high aeration during the start-up is required to enhance the copepod bloom. The density of live food is checked to ensure a sufficient density before the stocking of shrimp post larvae.

This particular farm consists of four ponds of 2.5 mu each (one mu = 1666 m2) with a depth of 80 cm. The farm receives oceanic water from South China Sea. The water pH was 8 at noon.

Usually the PL15 of whiteleg shrimp, Litopenaeus vannamei are stocked at density which could range from 30-100 pcs/m2 depending on the intensity level.

Permanent link to this article: http://fishconsult.org/?p=14084

Aug 15 2017

Grass carp in Brazil (Video)

Video credit: Herman Hennig (Argentina)
Review: Abdel Rahman El Gamal (Founder of the video channel)

According to published reports, grass carp (Ctenopharyngodon idellus) was first introduced into Brazil by the government in 1968 from Hungary. Afterward, the species was introduced in 1979 along with other Chinese carps by CEPTA/IBAMA (Research and Training Center in Aquaculture), State of Sao Paulo.

Carp polyculture in Brazil has been promoted as a complementary rural activity for small-scale family farmers in southern Brazil whereas farmers’ associations such as Braspeixe organizes a fish festival during which different carp dishes are offered to the public. In such small-scale farms, on-farm and/or commercial inputs to fertilize and feed carp in polyculture systems.

Some farms stock grass carp along with other species in recreation fishing centers which attract interested people.

The contribution of grass carp to Brazilian aquaculture seems not that significant especially when all species of carps, barbels, and other cyprinids are grouped in the FAO statistics whereas their combined production amounted 20,693 tons in 2015 compared to the total aquaculture production which amounted 575,260 tons in the same year. However, grass carp –along with other exotic species- represent to researchers an experimental fish species for a variety of research projects including spawning induction and genetic analysis.

Permanent link to this article: http://fishconsult.org/?p=14079

Aug 15 2017

Duckling azolla rush (Video)

Video credit: The Azolla Foundation
Review: Abdel Rahman El Gamal (Founder of the video channel)

 

 

This 30-second video shows the strong attractions of small ducks to azolla. The handful of azolla was totally consumed within the 30-sec duration of the video indicating the excellent palatability of azolla to the ducklings. It may worth mentioning that the ducklings were not scare upon picking the azolla from the human hand.

https://youtu.be/buEJ7zC8-jE

 

Permanent link to this article: http://fishconsult.org/?p=14076

Aug 15 2017

Sole culture in shrimp ponds in Egypt

Photos credit: Sherif Sadek (Egypt)

Review: Sherif Sadek and Abdel Rahman El Gamal (Founder of the website)

 

The farm is located near Port-Said whereas this Exploratory testing of the culture of Senegalese sole (Solea senegalensis) in the ponds of the brown shrimp (Farfantepenaeus aztecus). This is the first time to practice such polyculture system in Egypt bearing in mind that the brown shrimp is a new comer to Egyptian waters.

The fry of soles as well as the brown shrimp post larvae were collected from nature on 08 March, 2017. Upon collection and stocking, the average weight of sole was 0.3 gm/fish. Based on the subsequent sampling after 57 days of culture (May 04), the average weight of soles was 8 gm/fish.

Realizing the feeding habits and so the competition between soles and shrimp as both are benthic feeders, the stocking rate of sole being 0.5 fish/m2 is considered very low.

The feeding in this polyculture system is done using shrimp feed (34% CP). In fact, the protein content of the feed seems low for soles, but the growth rate is so far satisfactory. The outcome of the exploratory testing would be known once harvesting takes place.

 

 

Permanent link to this article: http://fishconsult.org/?p=14074

Aug 15 2017

Farming of tilapia and African catfish in irrigation ponds in Algeria

Photo credit: Gabriel de Labra (Spain)

Review: Gabriel de Labra and Abdel Rahman El Gamal (Founder of the website)

 

 

The inserted photo was taken in the area of In Salah, in the middle of Algeria. The small concrete pond shown in the photo is a typical irrigation tank which is currently used for fish culture especially for tilapia and African catfish. At the moment, there are many of those tanks which were built several years ago for irrigation purposes in different desert areas and nowadays the people in such regions are trying to use them also for aquaculture. It is believed that farmers once acquire the basic knowledge on fish culture, these irrigation tanks could produce decent quantities of high quality fish to the people in desert areas at not much additional construction costs.

 

 

Permanent link to this article: http://fishconsult.org/?p=14072

Aug 05 2017

Country report- Argentina (2015)- in Spanish

A permission from the report owner has been granted to publish the report on this website

cover-country-report-argentina-2115

 

 

 

 

 

 

 

 

 

[gview file=”http://fishconsult.org/wp-content/uploads/2016/12/Country-report-Argentina-2115.pdf”]

Permanent link to this article: http://fishconsult.org/?p=13714

Jul 17 2017

Dotted Sea-slug (Peltodoris atromaculata)

Photo credit: Patricia Martin Cabrera

Review: Abdel Rahman El Gamal (Founder of the website)

 

 

The photo was taken in Granada (Spain)

Introduction: The species is a marine gastropod molluscs that belongs to the family Discodorididae, class Gastropoda and phylum Mollusca which has been known as Peltodoris atromaculata or sometimes reported as Discodoris atromaculata.

The Dotted Sea-Slug occurs in Mediterranean Sea and has been also observed on the Basque Coast & the Canary Islands in the nearby Atlantic Ocean and is especially found in dark and shady underwater areas at various depths. In particular, the species is usually found on the stony sponge on which it feeds exclusively.

Description: The Dotted Sea-Slug has an oval body and is easily recognized by its randomly distributed dark brown spots on a white background.  It is believed that these spots are clearly visible, probably have the function to signal to potential predators that the animal is not edible (aposematic coloration). When the animal is resting, the outline of his body is nearly circular and hard to the touch.  The average size is from 5 to 7 cm that can grow to approximately 12 cm in length.

Their simple and tiny eyes are able to discern little more than light and dark. The species has feather-like gills on the rear part of the body.  It has eight appendages on three branches and is used by the animal to breathe.  It also has also head-mounted sensory appendages enabling animals to smell and taste.

Feeding habits: The species feeds mainly on the sponge (Petrosia ficiformis) and accumulates natural chemical products, such as petroformynes, from the sponge and stores them in its bodies, rendering themselves distasteful to predators. Most species in the Discodorididae family are thought to feed at night on sponges, while during the day they search for dark areas or remain hidden under rocks.

Reproduction: Dotted sea-slugs are simultaneous hermaphroditic, which means that they have both male and female sex organs at the same time and can fertilize one another. After mating, sea slugs lay their spiral egg masses. Egg development can take between 5 and 50 days, depending on water temperature. Usually from eggs arise little planktonic larvae, called veliger, with shell, which will lose during metamorphosis, when they begin their benthonic life as adult.

 

 

Permanent link to this article: http://fishconsult.org/?p=14055

Jul 16 2017

Green tilapia: annoying in shrimp ponds but rewarding on market display (Egypt)

Photos credit: Sherif Sadek (Egypt)

Review: Abdel Rahman El Gamal (Founder of the website)

 

 

Green tilapia (Tilapia zillii) is usually treated as an unwanted species in fish ponds because the species matures at younger age and smaller size compared to farmed tilapia species such as Nile tilapia (the specimens shown –based on their color- are sexually mature. Added to that, green tilapia does not belong to mouth brooder tilapias and its eggs may pass the screen of a fish pond then grow, mature and reproduce leading to problems in the pond management. Because green tilapia is more tolerant to salinity than other tilapia species it would normally occur where other tilapias are absent.

The attached photos show the harvest of a shrimp pond in Egypt showing specimens of whiteleg shrimp (Litopenaeus vannamei) along with green tilapia. Interestingly, green tilapia enjoys premium market price if displayed as it is often kept for special customers who are fond of the taste and row of the species and who can afford its price.

 

 

Permanent link to this article: http://fishconsult.org/?p=14052

Jul 16 2017

Honeycomb moray eel (Gymnothorax favagineus) in Damaniyat Island, Oman (Video)

Video client: Patricia Martin Cabrera

Review: Abdel Rahman El Gamal (Founder of the video channel)

 

 

The video was filmed in Damaniyat Island (Al Batinah region), Sultanate of Oman. The honeycomb moray eel, Gymnothorax favagineus shown in the video is a species of marine fish in the family Muraenidae and is one of the largest of Indo-Pacific morays and can grow up to 2-m length with a maximum length of about 3-m. The species which is also known as laced moray and leopard moray is a fearsome predator with powerful jaws.

Distribution and habitats: The honeycomb moray is widespread throughout the Indo-West Pacific area from eastern coast of Africa, Red Sea included, until Papua New Guinea and from south Japan to the Great Barrier Reef. It lives on the outer slopes of coral reefs. During the day, it sits sheltered in crevices at depths between 1 and 45 meters.

The honeycomb moray is carnivorous; it leaves its lair at night to actively hunt its preys along the reef. It feeds mainly on small fish and cephalopods. Large adults are prone to be aggressive in the wild. As shown in the video, the honeycomb moray eel lays in wait for prey between the corals.

The blotches shown on the specimen’s body may vary in size and color, often in relation to the habitat in which the animals live; morays live in clear coral reefs usually have proportionally less black than those found in turbid environments.

 

 

Permanent link to this article: http://fishconsult.org/?p=14045

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