2024 NECO FISHERIES: NECO Fisheries (Fishery) 2025 Legit Questions and Answers (6836)

(1a)

(i) Reduced availability of dissolved oxygen due to the dense growth of aquatic weeds, which can lead to suffocation and mortality of fingerlings.

(ii) Interference with the movement and feeding of fingerlings, as the weeds can create a physical barrier and obstruct their access to food.

(iii) Provision of hiding places for predators, which can increase the risk of predation on the fingerlings.

(iv) Accumulation of waste and decomposing organic matter, which can lead to the buildup of toxic substances and deterioration of water quality, affecting the overall health and growth of the fingerlings.

(1bi)

Spillway: A spillway is a structure designed to safely pass excess water from a dam, reservoir, or other water-retaining structure. It helps to prevent the overtopping and potential failure of the structure during high-flow events.

(1bii)

Fish sampling: Fish sampling is the process of collecting a representative sample of fish from a water body to assess the population characteristics, such as species composition, size distribution, and abundance. This information is crucial for fisheries management and monitoring.

(1biii)

Cropping: In aquaculture, cropping refers to the harvesting of fish or other aquatic organisms from a culture system. It involves the selective removal of individuals based on their size, age, or market demand, ensuring the efficient utilization of the 'copied from e x a m p l a z a . c o m free' available resources and maintaining the productivity of the system.

(1biv)

Feeding regime: The feeding regime in aquaculture refers to the pattern and frequency of feeding the cultured organisms. It involves the determination of the appropriate amount, timing, and composition of the feed to meet the nutritional requirements of the species and optimize their growth and health.

(1ci)

[In a Tabular Form]

-Intensive culture system-

(PICK ANY TWO)

(i) High stocking density

(ii) Reliance on artificial feeding

(iii) Controlled environmental conditions

(iv) Higher capital and operational costs

(v) Increased risk of disease outbreaks

(vi) Higher productivity per unit area

-Extensive culture system-

(PICK ANY TWO)

(i) Low stocking density

(ii) Reliance on natural food sources

(iii) Less control over environmental factors

(iv) Lower capital and operational costs

(v) Lower risk of disease outbreaks

(vi) Lower productivity per unit area

(1cii)

(PICK ANY FOUR)

(i) Provision of a reliable source of animal protein

(ii) Generation of employment opportunities

(iii) Diversification of the agricultural sector

(iv) Contribution to food security and poverty alleviation

(v) Potential for export and foreign exchange earnings

(vi) Promotion of sustainable utilization of aquatic 'copied from e x a m p l a z a . c o m free' resources

(3a)

(PICK ANY FIVE)

(i) Broodstock selection and management: Selecting healthy, sexually mature male and female fish with desirable characteristics.

(ii) Hormonal induction of spawning: Administering hormones to induce the release of eggs and sperm from the broodstock.

(iii) Egg fertilization: Mixing the released eggs and sperm to facilitate fertilization.

(iv) Egg incubation: Providing the appropriate conditions (temperature, water quality, etc.) for the fertilized eggs to develop and hatch.

(v) Larval rearing: Caring for the newly hatched larvae, providing them with the necessary nutrients and environmental conditions for growth and survival.

(vi) Fingerling production: Rearing the larvae into fingerlings, which are then ready for stocking in nursery or grow-out ponds.

(3bi)

(PICK ANY TWO)

(i) Reduce water supersaturation levels by aeration or adjusting water flow.

(ii) Identify and eliminate the source of gas supersaturation (e.g., clogged or malfunctioning aeration equipment).

(iii) Quarantine affected ponds to prevent the transfer of infected fish to other ponds.

(iv) Regularly monitor water quality parameters, especially dissolved gas levels.

(v) Improve water circulation and mixing to prevent localized gas supersaturation.

(vi) Treat affected fish with appropriate medications or remedies to alleviate the condition.

(3bii)

-Extensive fish 'copied from e x a m p l a z a . c o m free' farming-

(PICK ANY TWO)

(i) Low stocking density

(ii) Reliance on natural food sources

(iii) Minimal external inputs (e.g., feed, fertilizers)

(iv) Lower capital and operational costs

(v) Lower productivity per unit area

(vi) Dependence on natural environmental conditions

-Intensive fish farming-

(PICK ANY TWO)

(i) High stocking density

(ii) Reliance on artificial feeding

(iii) Requirement for external inputs (e.g., feed, aeration, water treatment)

(iv) Higher capital and operational costs

(v) Higher productivity per unit area

(vi) Greater control over environmental conditions

(3ci)

Monoculture refers to the cultivation or farming of a single species of organism, such as a single fish species, in a given aquaculture system.

(3cii)

(PICK ANY THREE)

(i) Chlorine

(ii) Iodine

(iii) Formalin

(iv) Hydrogen peroxide

(v) Potassium permanganate

(vi) Benzalkonium chloride

(3ciii)

(PICK ANY FOUR)

(i) Viral Nervous Necrosis (VNN)

(ii) Viral Hemorrhagic Septicemia (VHS)

(iii) Infectious Pancreatic Necrosis (IPN)

(iv) Koi Herpesvirus Disease (KHV)

(v) Spring Viremia of

Carp (SVC)

(vi) Infectious Hematopoietic Necrosis (IHN)

(4a)

(PICK ANY FOUR)

(i) Water quality

(ii) Stocking density

(iii) Transport duration

(iv) Acclimatization

(v) Oxygen supply

(vi) Handling and containers

(4bi)

(PICK ANY THREE)

(i) Higher catch and production volumes

(ii) Improved efficiency and technology

(iii) Access to larger and more distant fishing grounds

(iv) Potential for export and international trade

(v) Economies of scale and profitability

(vi) Ability to meet the growing demand for seafood

(4bii)

(i) Potential for overfishing and depletion of fish stocks

(ii) Environmental impact from large-scale fishing operations

(4ci)

[In Tabular Form]

-Fresh fish-

(PICK ANY TWO)

(i) Shorter shelf life

(ii) Requires refrigeration or ice for preservation

(iii) Milder flavor

(iv) Softer texture

(v) Higher moisture content

(vi) Shorter preparation time

-Smoked fish-

(PICK ANY TWO)

(i) Longer shelf life

(ii) Can be stored at room temperature

(iii) Stronger, more distinct flavor

(iv) Firmer texture

(v) Lower moisture content

(vi) Longer preparation time (smoking process)

(4cii)

(PICK ANY FOUR)

(i) Water quality management

(ii) Feeding and nutrition management

(iii) Disease prevention and treatment

(iv) Pond/tank 'copied from e x a m p l a z a . c o m free' maintenance and cleaning

Stocking density and population control

(vi) Harvest and post-harvest handling

(4ciii)

Length = 92,000 cm

Breadth = 62,000 cm

Area = Length x Breadth

Area = 92,000 cm x 62,000 cm

Area = 5,704,000,000 cm²

Area = 5,704,000 m²

Therefore, the area of the rectangular pond is 5,704,000 m²

(5a)

(CHOOSE ANY FOUR)

(i) Ice

(ii) Salt

(iii) Smoking

(iv) Freezing Equipment

(v) Canning

(vi) Drying Racks

(vii) Vacuum Sealing

(viii) Chemical Preservatives

(5b)

(CHOOSE ANY TWO)

(i) Tilapia has a more compressed, oval body, while catfish has a more elongated, cylindrical body.

(ii) Tilapia prefers warmer, shallower waters, while catfish can thrive in a variety of water conditions, including deeper and cooler waters.

(iii) Tilapia are mouthbrooders, while catfish typically lay eggs in nests.

(iv) Tilapia are primarily herbivores or omnivores, feeding on algae and plant material, whereas catfish are more carnivorous, feeding on smaller fish and invertebrates.

(v) Catfish have prominent barbels (whiskers), while tilapia do not.

(5ci)

(CHOOSE ANY FOUR)

(i) Poor Water Quality: High levels of ammonia or low oxygen can lead to fish deaths.

(ii) Disease Outbreaks: Infections caused by bacteria, viruses, or parasites.

(iii) Overcrowding: Leads to increased stress and susceptibility to disease.

(iv) Inadequate Nutrition: Lack of proper nutrients can weaken fish and increase mortality.

(v) Temperature Fluctuations: Sudden changes in water temperature can stress and kill fish.

(vi) Predation: Predatory birds, animals, or other fish can reduce stock.

(vii) Chemical Contamination: Pesticides or industrial 'copied from e x a m p l a z a . c o m free' pollutants in the water.

(5cii)

(CHOOSE ANY THREE)

(i) Borehole Water

(ii) River or Stream Water

(iii) Rainwater Harvesting

(iv) Reservoir or Dam Water

(vi) Municipal Water Supply

(5ciii)

(CHOOSE ANY FIVE)

(i) Exoskeleton: Hard, protective outer shell.

(ii) Antennae: Long, sensory appendages on the head.

(iii) Claws (Chelae): Large pincers used for defense and feeding.

(iv) Segmented Body: Body divided into the cephalothorax and abdomen.

(v) Swimmerets: Small appendages under the abdomen used for swimming and carrying eggs in females.

(vi) Eyes on Stalks: Crayfish have compound eyes on movable stalks.

(vii) Telson and Uropods: Tail fan used for swimming and quick backward movements.