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Chondrichthyes.
This document provides information about sharks, skates, and rays (Chondrichthyes). It discusses their habitats in temperate and cold, deep waters. It describes how they hunt and feed near coastal areas. The document also outlines the evolution of Chondrichthyes, noting their appearance in the Devonian period and placoderm ancestors. Key adaptations like cartilage skeletons, spiral valves, and specialized jaws are also summarized.
Gastropods reproductive system
Two gonads in gastropods release eggs or sperm into the coelom cavity, from which the kidneys extract and release them into the mantle cavity and then to the external environment. Gastropods can reproduce through internal fertilization if hermaphroditic, or external fertilization by releasing eggs and sperm into water. Fertilized eggs become trochophore larvae and then veliger larvae, going through metamorphosis to become juvenile and adult gastropods.
ASIAN SEABASS CULTURE
Asian sea bass (Lates calcarifer) is an important species for aquaculture in Southeast Asia. It can be cultured in both freshwater and saltwater. Major issues in sea bass culture include cannibalism in young stages, dependence on high protein feed sources, and unpredictable wild fry availability. Sea bass nursery rearing is typically done in earthen ponds, concrete tanks, or net cages with fry stocked at high densities. Grow-out is usually done in ponds or cages at lower stocking densities, feeding on trash fish. Sea bass polyculture with tilapia is also common, with sea bass reaching market size of 600g within 4-5 months.
Fish
This document provides an overview of fish classification and types. It discusses the three main classes of fish: Agnatha (jawless fish such as lampreys and hagfish), Chondrichthyes (cartilaginous fish like sharks and rays), and Osteichthyes (bony fish including over 20,000 species such as salmon and tuna). Key details are provided on characteristics like respiration, circulation, adaptations, and reproduction for the different fish classes. Examples of specific fish species are also mentioned like coelacanth, cichlids, pufferfish, and fugu.
Apresentação1 molusco
Os moluscos são animais marinhos, de água doce e terrestres importantes economicamente, como ostras e mariscos comestíveis. O cultivo de moluscos marinhos vem crescendo no Brasil, trazendo benefícios econômicos e impactos ambientais. As classes de moluscos incluem gastrópodes como caramujos, bivalves como ostras e mexilhões, e cefalópodes como polvos e lulas.
Morphology of Fish Testes
The testes of fish are paired elongated organs that are attached to the dorsal wall of the body cavity. Within the testes are seminiferous tubules containing germ cells that undergo spermatogenesis to produce sperm, and Leydig cells that produce testosterone. Teleost fish have either lobular or tubular testes organized into lobules or tubules. Elasmobranch testes do not contain seminiferous tubules and can be diametric, radial, or compound in morphology. Knowledge of fish testes morphology provides insight into fish reproduction and conservation.
Fishes
This document discusses chordates and vertebrates. It notes that vertebrates have backbones and belong to the phylum chordata. It also describes two other chordate groups, lancelets and tunicates. Key characteristics of chordates include having a tail, nerve cord, pharyngeal pouches and notochord. The document then focuses on characteristics of vertebrates like their backbone and skull. It classifies vertebrates as either warm-blooded or cold-blooded. Finally, it outlines the three classes of fish and characteristics like breathing with gills and reproduction through external fertilization.
Recommended
Chondrichthyes.
This document provides information about sharks, skates, and rays (Chondrichthyes). It discusses their habitats in temperate and cold, deep waters. It describes how they hunt and feed near coastal areas. The document also outlines the evolution of Chondrichthyes, noting their appearance in the Devonian period and placoderm ancestors. Key adaptations like cartilage skeletons, spiral valves, and specialized jaws are also summarized.
Gastropods reproductive system
Two gonads in gastropods release eggs or sperm into the coelom cavity, from which the kidneys extract and release them into the mantle cavity and then to the external environment. Gastropods can reproduce through internal fertilization if hermaphroditic, or external fertilization by releasing eggs and sperm into water. Fertilized eggs become trochophore larvae and then veliger larvae, going through metamorphosis to become juvenile and adult gastropods.
ASIAN SEABASS CULTURE
Asian sea bass (Lates calcarifer) is an important species for aquaculture in Southeast Asia. It can be cultured in both freshwater and saltwater. Major issues in sea bass culture include cannibalism in young stages, dependence on high protein feed sources, and unpredictable wild fry availability. Sea bass nursery rearing is typically done in earthen ponds, concrete tanks, or net cages with fry stocked at high densities. Grow-out is usually done in ponds or cages at lower stocking densities, feeding on trash fish. Sea bass polyculture with tilapia is also common, with sea bass reaching market size of 600g within 4-5 months.
Fish
This document provides an overview of fish classification and types. It discusses the three main classes of fish: Agnatha (jawless fish such as lampreys and hagfish), Chondrichthyes (cartilaginous fish like sharks and rays), and Osteichthyes (bony fish including over 20,000 species such as salmon and tuna). Key details are provided on characteristics like respiration, circulation, adaptations, and reproduction for the different fish classes. Examples of specific fish species are also mentioned like coelacanth, cichlids, pufferfish, and fugu.
Apresentação1 molusco
Os moluscos são animais marinhos, de água doce e terrestres importantes economicamente, como ostras e mariscos comestíveis. O cultivo de moluscos marinhos vem crescendo no Brasil, trazendo benefícios econômicos e impactos ambientais. As classes de moluscos incluem gastrópodes como caramujos, bivalves como ostras e mexilhões, e cefalópodes como polvos e lulas.
Morphology of Fish Testes
The testes of fish are paired elongated organs that are attached to the dorsal wall of the body cavity. Within the testes are seminiferous tubules containing germ cells that undergo spermatogenesis to produce sperm, and Leydig cells that produce testosterone. Teleost fish have either lobular or tubular testes organized into lobules or tubules. Elasmobranch testes do not contain seminiferous tubules and can be diametric, radial, or compound in morphology. Knowledge of fish testes morphology provides insight into fish reproduction and conservation.
Fishes
This document discusses chordates and vertebrates. It notes that vertebrates have backbones and belong to the phylum chordata. It also describes two other chordate groups, lancelets and tunicates. Key characteristics of chordates include having a tail, nerve cord, pharyngeal pouches and notochord. The document then focuses on characteristics of vertebrates like their backbone and skull. It classifies vertebrates as either warm-blooded or cold-blooded. Finally, it outlines the three classes of fish and characteristics like breathing with gills and reproduction through external fertilization.
Class chondrichtyes Group 4
This document summarizes key anatomical features of cartilaginous fishes. It describes that they have cartilaginous skeletons, paired fins, and gills for respiration. It provides details on various external features like dermal denticles, claspers, lateral line canals, and fins. Internally, it discusses respiration through gills, spiracles that provide oxygen to the eyes and brain, and heterocercal tails that aid in locomotion.
Squid
Squid are cephalopods that live in oceans around the world. They have bilateral symmetry, a mantle, arms, and two longer tentacles. Squid can change color using chromatophores in their skin. They are strong swimmers that feed on small fish, crabs, and shrimp using their two tentacles and beak. Squid are an important food source for larger marine animals and are also fished commercially and eaten by humans.
Class Cephalopoda Notes
Cuttlefish, squids, octopuses, and nautiloids are examples of cephalopods, which are head-foot mollusks named for having their head situated directly above their foot-like mantle. Cephalopods are the most complex mollusks and invertebrates, having closed circulatory systems and, except for nautiloids, no external shell. They propel themselves using jet propulsion from their mantle cavity and many have internal shells like the cuttlebone to provide buoyancy.
Pearl Oyster Hatchery.pptx
The document summarizes techniques for pearl oyster hatchery operations, including broodstock development, induced spawning, larval rearing, and algal culture units. Broodstock are reared using raft, rack, or onshore tank cultures. Ripe oysters are induced to spawn through thermal or chemical stimulation. Larval development proceeds through trochophore, veliger, pediveliger, plantigrade, and spat stages over 3 months. Isochrysis galbana and mixed algae are cultured to feed the larvae and spat. Proper environmental conditions and feeding practices are required to grow pearl oysters from fertilization to spat.
Los peces
Los peces son vertebrados acuáticos viven en aguas dulces y saladas los peces tienen fusiforme al igual que su respiración es branquial y su reproducción es sexual son ovíparos como ovovivíparos
03. Carrying Capacity estimation White 1
This document discusses aquaculture carrying capacity case studies in the Philippines. It examines three small-scale aquaculture areas: Bolinao and Anda, Dagupan estuary, and Taal Lake. For each area, it provides information on the types and amounts of aquaculture present, as well as any issues with recurring fish kills. It then discusses estimating carrying capacity through modeling nutrient inputs and outputs, and how water exchange rates and precipitation can impact this capacity. The goal is to help sustainably manage cumulative aquaculture impacts on shared water bodies.
Shellfish knowledge: www.chefqtrainer.blogspot.com
This document provides information about different types of shellfish, including categories, purchasing and storage tips, and descriptions. It discusses crustaceans like lobster, shrimp, crab; echinoderms like sea urchins; and mollusks like bivalves (clams, oysters), univalves (whelks), and cephalopods (octopus, squid). Specific details are provided on species of lobster, shrimp, crab. Storage instructions emphasize purchasing live shellfish and avoiding refreezing. Mollusks are further described, including oyster species and factors influencing taste.
Chapter 7 - Marine Invertebrates
Marine invertebrates are animals without backbones that live in ocean environments. They make up at least 97% of all animal species and include sponges, cnidarians like jellyfish and corals, worms, molluscs like clams and octopuses, and arthropods like crustaceans. Many are filter feeders that eat plankton or detritus and play important ecological roles in ocean ecosystems.
Pgs 504 ppt
This document discusses advances in fish processing technology in India. It describes several technologies used for freezing and preserving fish products, including block freezing, individually quick freezing (IQF), and value-added products like fish oil capsules and surimi. New processing methods are also summarized, such as irradiation, retort pouch processing, and extrusion. The document concludes by mentioning two research institutes in India - the Central Institute of Fisheries Technology and the National Institute of Fisheries Post Harvest Technology and Training - that work to develop technologies and train individuals in fish processing.
TRAITS OF IMPORTANT CULTIVABLE FISH AND SHELLFISH & THEIR CULTURE METHODS
TRAITS OF IMPORTANT CULTIVABLE FISH AND SHELLFISH & THEIR CULTURE METHODSSHUBHAM PATIDAR FISHERIES ADDAA
This document discusses the traits and culture methods of important cultivable fish and shellfish in fresh water aquaculture. It covers carp species like Catla catla and Labeo rohita that are commonly farmed using methods like polyculture. Exotic carp species such as the silver carp are also discussed. Culture methods for catfish including Clarias batrachus are described. Finally, the giant freshwater prawn Macrobrachium rosenbergii is covered, noting its life cycle and that it can be cultured alone or with other species.Fish anatomy
This document provides information about fish anatomy and aging fish using otoliths. It describes the external anatomy of fish such as fins, scales, lateral line and internal anatomy including organs like gills, kidneys and gonads. It explains that otoliths are structures behind the brain that help with balance and hearing and can be used to determine a fish's age by counting growth rings. Validating the age estimates involves techniques like tagging and recapturing fish or rearing them in laboratories to compare known ages to otolith ring counts.
Estuaries: Communities
This document describes different estuarine communities, including open water, mudflats, salt marshes, mangrove forests, and other communities like seagrass beds and oyster reefs. It discusses the characteristic species found in each community and their roles, like cordgrass and fiddler crabs in salt marshes or red, black, and white mangroves in mangrove forests. However, many estuarine communities are being destroyed by human activities like reclamation, dredging, shrimp farming, and coastal development.
Migration in Fish
Migration in fish including different types of movements, types of migration, physiological changes during migration and challenges during navigation is shared in the presentation. it is useful for the students studying ichthyology at PG level.
Introduction of exotic species in india
The document discusses the introduction of exotic fish species in Indian aquaculture. It provides examples of exotic species introduced, such as common carp, bighead carp, tilapia, and white leg shrimp. While the introduction of exotic species provided some economic benefits, it also caused ecological impacts like competition with native species, loss of biodiversity, and transmission of diseases. Proper management of introductions is needed to balance benefits with minimizing risks to the environment.
Animais ii (2)
Este documento descreve a evolução dos cordados, começando pelos protocordados que mantêm a notocorda por toda a vida, como o anfioxo. Apresenta os cordados craniados sem mandíbula, como as lampreias e feiticeiras. Por fim, explica a transformação da notocorda em coluna vertebral nos demais craniados, como peixes, anfíbios, répteis, aves e mamíferos.
fish predation
Marine fish employ a variety of behavioral and morphological adaptations to avoid predation. Behaviorally, fish school together for safety in numbers, migrate to safer habitats, and care for offspring. Morphologically, fish have body shapes and colors that camouflage them, strong fins and scales for defense, senses like lateral lines to detect predators, and some can even shock or fly away from threats. Both behavioral and physical adaptations are crucial for the survival of prey fish and maintenance of ecosystem balance.
REINO ANIMAL Lic. Javier Cucaita
Este documento describe las características generales de los reinos animales. Explica que los animales son pluricelulares y se desarrollan mediante mitosis. Se dividen en invertebrados como poríferos, cnidarios, platelmintos, anélidos, nemertelmintos, moluscos, artrópodos y equinodermos. También incluye vertebrados como peces, anfibios, reptiles, aves y mamíferos. Detalla las estructuras y hábitats propios de cada filo.
Fish_Gill.pptx
Fishes rely on gills for respiration. The gills consist of gill arches that support gill filaments. In most fishes, the gills are located within pouches or chambers. Gas exchange occurs through blood vessels in the thin epithelium of the numerous secondary lamellae that project from the filaments. The structure and organization of the gills varies across fish groups but generally allows for countercurrent flow that maximizes oxygen uptake from water passing over the gills.
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What's hot
Class chondrichtyes Group 4
This document summarizes key anatomical features of cartilaginous fishes. It describes that they have cartilaginous skeletons, paired fins, and gills for respiration. It provides details on various external features like dermal denticles, claspers, lateral line canals, and fins. Internally, it discusses respiration through gills, spiracles that provide oxygen to the eyes and brain, and heterocercal tails that aid in locomotion.
Squid
Squid are cephalopods that live in oceans around the world. They have bilateral symmetry, a mantle, arms, and two longer tentacles. Squid can change color using chromatophores in their skin. They are strong swimmers that feed on small fish, crabs, and shrimp using their two tentacles and beak. Squid are an important food source for larger marine animals and are also fished commercially and eaten by humans.
Class Cephalopoda Notes
Cuttlefish, squids, octopuses, and nautiloids are examples of cephalopods, which are head-foot mollusks named for having their head situated directly above their foot-like mantle. Cephalopods are the most complex mollusks and invertebrates, having closed circulatory systems and, except for nautiloids, no external shell. They propel themselves using jet propulsion from their mantle cavity and many have internal shells like the cuttlebone to provide buoyancy.
Pearl Oyster Hatchery.pptx
The document summarizes techniques for pearl oyster hatchery operations, including broodstock development, induced spawning, larval rearing, and algal culture units. Broodstock are reared using raft, rack, or onshore tank cultures. Ripe oysters are induced to spawn through thermal or chemical stimulation. Larval development proceeds through trochophore, veliger, pediveliger, plantigrade, and spat stages over 3 months. Isochrysis galbana and mixed algae are cultured to feed the larvae and spat. Proper environmental conditions and feeding practices are required to grow pearl oysters from fertilization to spat.
Los peces
Los peces son vertebrados acuáticos viven en aguas dulces y saladas los peces tienen fusiforme al igual que su respiración es branquial y su reproducción es sexual son ovíparos como ovovivíparos
03. Carrying Capacity estimation White 1
This document discusses aquaculture carrying capacity case studies in the Philippines. It examines three small-scale aquaculture areas: Bolinao and Anda, Dagupan estuary, and Taal Lake. For each area, it provides information on the types and amounts of aquaculture present, as well as any issues with recurring fish kills. It then discusses estimating carrying capacity through modeling nutrient inputs and outputs, and how water exchange rates and precipitation can impact this capacity. The goal is to help sustainably manage cumulative aquaculture impacts on shared water bodies.
Shellfish knowledge: www.chefqtrainer.blogspot.com
This document provides information about different types of shellfish, including categories, purchasing and storage tips, and descriptions. It discusses crustaceans like lobster, shrimp, crab; echinoderms like sea urchins; and mollusks like bivalves (clams, oysters), univalves (whelks), and cephalopods (octopus, squid). Specific details are provided on species of lobster, shrimp, crab. Storage instructions emphasize purchasing live shellfish and avoiding refreezing. Mollusks are further described, including oyster species and factors influencing taste.
Chapter 7 - Marine Invertebrates
Marine invertebrates are animals without backbones that live in ocean environments. They make up at least 97% of all animal species and include sponges, cnidarians like jellyfish and corals, worms, molluscs like clams and octopuses, and arthropods like crustaceans. Many are filter feeders that eat plankton or detritus and play important ecological roles in ocean ecosystems.
Pgs 504 ppt
This document discusses advances in fish processing technology in India. It describes several technologies used for freezing and preserving fish products, including block freezing, individually quick freezing (IQF), and value-added products like fish oil capsules and surimi. New processing methods are also summarized, such as irradiation, retort pouch processing, and extrusion. The document concludes by mentioning two research institutes in India - the Central Institute of Fisheries Technology and the National Institute of Fisheries Post Harvest Technology and Training - that work to develop technologies and train individuals in fish processing.
TRAITS OF IMPORTANT CULTIVABLE FISH AND SHELLFISH & THEIR CULTURE METHODS
TRAITS OF IMPORTANT CULTIVABLE FISH AND SHELLFISH & THEIR CULTURE METHODSSHUBHAM PATIDAR FISHERIES ADDAA
This document discusses the traits and culture methods of important cultivable fish and shellfish in fresh water aquaculture. It covers carp species like Catla catla and Labeo rohita that are commonly farmed using methods like polyculture. Exotic carp species such as the silver carp are also discussed. Culture methods for catfish including Clarias batrachus are described. Finally, the giant freshwater prawn Macrobrachium rosenbergii is covered, noting its life cycle and that it can be cultured alone or with other species.Fish anatomy
This document provides information about fish anatomy and aging fish using otoliths. It describes the external anatomy of fish such as fins, scales, lateral line and internal anatomy including organs like gills, kidneys and gonads. It explains that otoliths are structures behind the brain that help with balance and hearing and can be used to determine a fish's age by counting growth rings. Validating the age estimates involves techniques like tagging and recapturing fish or rearing them in laboratories to compare known ages to otolith ring counts.
Estuaries: Communities
This document describes different estuarine communities, including open water, mudflats, salt marshes, mangrove forests, and other communities like seagrass beds and oyster reefs. It discusses the characteristic species found in each community and their roles, like cordgrass and fiddler crabs in salt marshes or red, black, and white mangroves in mangrove forests. However, many estuarine communities are being destroyed by human activities like reclamation, dredging, shrimp farming, and coastal development.
Migration in Fish
Migration in fish including different types of movements, types of migration, physiological changes during migration and challenges during navigation is shared in the presentation. it is useful for the students studying ichthyology at PG level.
Introduction of exotic species in india
The document discusses the introduction of exotic fish species in Indian aquaculture. It provides examples of exotic species introduced, such as common carp, bighead carp, tilapia, and white leg shrimp. While the introduction of exotic species provided some economic benefits, it also caused ecological impacts like competition with native species, loss of biodiversity, and transmission of diseases. Proper management of introductions is needed to balance benefits with minimizing risks to the environment.
Animais ii (2)
Este documento descreve a evolução dos cordados, começando pelos protocordados que mantêm a notocorda por toda a vida, como o anfioxo. Apresenta os cordados craniados sem mandíbula, como as lampreias e feiticeiras. Por fim, explica a transformação da notocorda em coluna vertebral nos demais craniados, como peixes, anfíbios, répteis, aves e mamíferos.
fish predation
Marine fish employ a variety of behavioral and morphological adaptations to avoid predation. Behaviorally, fish school together for safety in numbers, migrate to safer habitats, and care for offspring. Morphologically, fish have body shapes and colors that camouflage them, strong fins and scales for defense, senses like lateral lines to detect predators, and some can even shock or fly away from threats. Both behavioral and physical adaptations are crucial for the survival of prey fish and maintenance of ecosystem balance.
REINO ANIMAL Lic. Javier Cucaita
Este documento describe las características generales de los reinos animales. Explica que los animales son pluricelulares y se desarrollan mediante mitosis. Se dividen en invertebrados como poríferos, cnidarios, platelmintos, anélidos, nemertelmintos, moluscos, artrópodos y equinodermos. También incluye vertebrados como peces, anfibios, reptiles, aves y mamíferos. Detalla las estructuras y hábitats propios de cada filo.
Fish_Gill.pptx
Fishes rely on gills for respiration. The gills consist of gill arches that support gill filaments. In most fishes, the gills are located within pouches or chambers. Gas exchange occurs through blood vessels in the thin epithelium of the numerous secondary lamellae that project from the filaments. The structure and organization of the gills varies across fish groups but generally allows for countercurrent flow that maximizes oxygen uptake from water passing over the gills.
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Shellfish knowledge: www.chefqtrainer.blogspot.com
Shellfish knowledge: www.chefqtrainer.blogspot.com
TRAITS OF IMPORTANT CULTIVABLE FISH AND SHELLFISH & THEIR CULTURE METHODS
TRAITS OF IMPORTANT CULTIVABLE FISH AND SHELLFISH & THEIR CULTURE METHODS
Similar to ձկներ (14)
ձկներ
- 1. Ձկների բազմազանությունը: Հայաստանում հանդիպող ձկները և դրանց պահպանությունը
- 2. Սևանի իշխան (լատիներեն՝ Salmo ischchan) — Սաղմոնների ընտանիքի ձուկ։ Տարածված է բացառապես Սևանա լճի ավազանում։ Միջին մեծության ձուկ է` արծաթափայլ թեփուկներով, խոշոր, սև՝ երբեմն էլ նարնջագույն կամ բաց վարդագույն պուտերով։
- 3. Հայաստանի տարածքում հանդիպող ձկնատեսակները պատկանում են 5 կարգի՝ սաղմոնազգիներ, ծածանազգիներ, լոքոազգիներ, ծածանատամազգիներ և պերկեսազգիներ: Հայաստանի էնդեմիկ ձկնատեսակներ են՝ Սևանի իշխան՝ իր 4 ենթատեսակներով, Հայկական կարմրակն, Հայկական տառեխիկ, Սևանի կողակ, Սևանի բեղլու,Հայկական գուստերա:
- 4. Նախկինում իշխանը Սևանի ամենակարևոր արդյունաբերական ձկնատեսակն էր։ Լճի մակարդակի իջեցման հետևանքով իշխանի բազմացման պայմանները էապես վատացան և ներկայումս այն վերացման եզրին է։ Ընդգրկված է «կարմիր գրքում»։ Ներկայումս վերարտադրության համար կարևոր դեր են խաղում ձկնաբուծարանները։ Իշխանը լավ է հարմարվում տարբեր տեսակի մաքուր ջրավազաններում։ Դասական օրինակ է Իսիկ-Կուլ լճում դրա տարածումը, ուր այն կազմեց նոր, հատուկ տարատեսակ։
- 5. Կարմրախայտ, սաղմոնազգիների ընտանիքի փոքր ձուկ։ Մաշկը շականակագույն է՝ սև, կարմիր և դեղնավուն պուտերով: Մարմնի երկարությունը 25-35 սմ, քաշը՝ 200-500 գրամ: Ապրում է լեռնային սառը, պարզ գետակներում: Սնվում է ջրի մեջ թափվող միջատներով, թրթուռներով, գորտերի շերեփուկներով: Հայաստանում բոլոր գետակներում եղել է, սակայն որոշ տեղեր ոչնչացել է: Կարմրախայտը սաղմոնաձկների ընտանիքի ձուկ է: Տարածված է գրեթե բոլոր գետերի (բացառությամբ` Սևանա լճի ավազանի) վերին և միջին հոսանքներում: Նախընտրում է թթվածնով հարուստ, խճապատ հատակով և արագահոս ջրերը: Սառնասեր է: Համեմատաբար խոշոր ձուկ է՝ կողքերից փոքր-ինչ սեղմված: Մարմնի երկարությունը 20-25 (երբեմն՝ մինչև 54) սմ է, զանգվածը՝ մինչև 2 կգ:
- 6. Կարմրախայտը Հայաստանի արժեքավոր ձկնատեսակներից է, որի պաշարները, սակայն, գրեթե սպառվել են, և ձուկը կորցրել է արդյունագործական նշանակությունը: Կատարվում են արհեստական պայմաններում կարմրախայտ բուծելու փորձեր:
- 7. Կողակը ծածանաձկների ընտանիքի ձուկ է` միջին չափի, մարմնի երկարությունը 35–40 (երբեմն՝ մինչև 50) սմ է, զանգվածը` մինչև 2 կգ: Ներկայումս կողակի պաշարները հանրապետությունում զգալի նվազել են, ուստի այն պաշտպանության և վերարտադրության կարիք ունի:
- 8. Ձկնամթերքը սննդային արժեքով չի զիջում մսեղենին և առավել դյուրամարս է: Թարմ ձուկը պարունակում է սպիտակուցներ, ճարպեր, նաև ածխաջրեր, վիտամիններ և հանքային նյութեր: Ձկան սպիտակուցը պարունակում է մարդուն անհրաժեշտ բոլոր անփոխարինելի ամինաթթուները, որոնք չեն սինթեզվում օրգանիզմում: Սննդում օգտագործվող ձկների 20%-ը քաղցրահամ ջրերի, 80%-ը ծովաձկներ են: Ձուկը լավորակ է, եթե ծածկված է թափանցիկ լորձով, ամուր կպած թեփուկներով, ունի վառ կարմիր խռիկներ և դուրս պրծած աչքեր, մկանային հյուսվածքն ամուր կպած է փշերին և դժվար է անջատվում: Ձուկն օգտագործում են նաև մշակած՝ աղ դրած, ապխտած, ծխահարած և այլն: Աղ դրած ձուկը կորցնում է սպիտակուցների, հանքային նյութերի և ջրալույծ վիտամինների որոշ մասը: