Food and feeding in fishes
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This document discusses the natural food and feeding habits of fishes. It covers different types of plankton, benthos, and detritus that serve as food sources for fishes based on their ecological niche. Various feeding classifications are described, including feeding types, trophic niches, and quantitative analyses of gut content. Structural modifications in fishes related to their different feeding habits are also mentioned.
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1) The digestive system of fish breaks down food through a series of organs from the mouth to the anus.
2) Fish use various feeding mechanisms to ingest food depending on their anatomy and food sources.
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This document discusses factors to consider when formulating fish feeds, including the nutrient requirements of different fish species. It explains that fish can be herbivores, carnivores, omnivores, or detritivores depending on their diets. The main nutrients required in fish feeds are proteins, lipids, carbohydrates, vitamins, and minerals. Acceptable protein sources include fish meal and soymeal, while lipid sources include fish and plant oils. Carbohydrates, vitamins, and minerals also must be included in proper amounts. The document stresses that feed formulations should be tailored to local availability and fish species' specific needs.
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Pond management
The document discusses pond construction, management, and fish stocking practices. It states that proper pond construction and watershed management are important for good fishing. It also discusses liming and fertilizing ponds to increase nutrients, selecting appropriate fish species, and keeping records of harvests. Stocking densities of 5-6 million spawn per hectare are recommended, with higher densities for cement cisterns. Feeding schedules after stocking and harvesting practices at 15 days are also outlined.
Lecture 1. history aquaculture
Aquaculture refers to culturing aquatic animals like fish, shrimp, and shellfish. It began over 4000 years ago when Sumerians kept fish in ponds. Ancient Egyptians, Romans, Chinese, and Indians also engaged in early forms of fish culture. In modern times, aquaculture has expanded globally and plays an important role in food production, economic growth, and employment. A wide variety of fish, shellfish, algae and other aquatic species are now farmed using advanced techniques.
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this slide describes about the methods, distribution, annual landings and important species of lobster and crabs in India.
Natural fish seed collection
Transport of hatchlings, fry, and fingerlings is common in aquaculture. Proper techniques involve understanding fish physiology and mortality causes during transport. Seed can be collected from wild or hatcheries. Major carps are collected from flooded rivers during monsoon season. Seed from estuaries and coastal waters include milkfish, mullets, pearlspot, and seabass. Bundhs are seasonal flooded areas that stimulate breeding. Induced spawning techniques breed species that don't spawn in captivity using hormones. Transport uses open or closed oxygenated systems. Factors causing mortality are oxygen depletion, waste accumulation, temperature fluctuations, and stress. Anaesthetics and antibiotics are used to reduce stress and prevent disease.
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Fish tagging methods allow biologists to gather information about fish populations. There are biological, chemical, and physical tagging methods. Biological methods use natural marks like parasites or morphology. Chemical methods involve immersing, injecting, or feeding fish dye to mark them. Physical methods include internal tags like coded wire tags or PIT tags, and external tags like strap tags, dart tags, and anchor tags. Tagging provides data on movement patterns, population estimates, growth, and mortality to further understanding of fisheries.
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The Aqua-vision concept of organic carp and backyard fish farming
The Aqua-vision concept of organic carp and backyard fish farmingCentre for Environment, Fisheries and Aquaculture Science (Cefas)
The document discusses the concepts of organic carp and backyard fish farming as sustainable forms of aquaculture. It explores raising carp and other species organically on small or backyard scales. Key challenges include developing adequate and cost-effective organic feed, improving pond productivity, and establishing appropriate markets. While questions remain, the document argues that small-scale, semi-intensive systems have potential if enthusiastic producers and researchers further develop the approaches.Pearson’s square
Pearson's Square is a method for determining the exact proportions of feedstuffs needed to produce a specific quantity of nutrient. It involves drawing a square and labeling feeds and their crude protein percentages on the left corners and feeds on the right corners to match. Numbers are then subtracted along the diagonal lines and parts of feeds are divided by the total parts to find the percentage of each feed in the ration. The total pounds needed are then used to determine the pounds of each feed, and the results are checked to ensure the protein needs are met.
Pearson square - Balancing Rations
The document describes how to use a Pearson Square to formulate animal feed rations by mixing different feed ingredients to achieve a desired protein or nutrient level. It provides an example of mixing corn soybean meal (CSM) and barley to create 600 lbs of 26% crude protein feed. The steps include: 1) Setting up the Pearson Square with feeds and desired protein, 2) Subtracting diagonally to determine parts of each feed, 3) Converting parts to percentages of the total, 4) Calculating pounds of each feed needed based on the total amount. The example determines 365 lbs of barley and 235 lbs of CSM are needed to achieve the 26% crude protein ration.
Fish Nutrition
Fish have more efficient feed conversion ratios than land animals like cows and pigs due to their biology and environment. Fish feeds are more concentrated in nutrients than feeds for land animals. A balanced nutrition mix for fish includes protein, fat, carbohydrates, vitamins, and minerals. Proper storage, water quality factors like oxygen, temperature, pH, alkalinity, hardness, ammonia, nitrite, and salinity are important for fish health. Routine water testing and monitoring of these factors is necessary in aquaculture.
Feed formulation
Feed formulation is the major part of aquaculture.The main objective of feed formulation is to utilize the knowledge of nutrient requirements, locally available feed ingredients and digestive capacity of fish for the development of a nutritionally balanced mixture of feed stuff…
Best Ingredient for Fish Meal - King Fish Group
Now we are produce Frozen seafood and Fresh Seafood in all over world at very competitive price. We are also deals in Steamed Sterilized Fish Meal, Dehydrated Squid Meal, Sundry Fish meal and Much More.
Comparitive study of fishes
This document summarizes a comparative study on the morphological adaptations of the alimentary canal in three fish species: Sardinella longiceps, Thunnus obesus, and Rastrelliger kanagurta. The objectives were to compare the alimentary canal morphology and calculate the relative length of the gut for each fish. The study found that alimentary canal structure varies depending on feeding habits. S. longiceps, an herbivore, had the longest relative gut length of 1.868. T. obesus, a carnivore, had the shortest at 0.272. R. kanagurta as an omnivore was intermediate at 1.033. The morphological variations in
Internetblog presentation
This document discusses starting a blog about breeding freshwater cichlid fish and invertebrates. The blog would target males and females aged 18-65 who are heavily involved in the hobby. It would include topics like introductions to cichlids and shrimp, breeding techniques, feeding for breeding, and caring for eggs and fry. The blog would utilize social media platforms like Facebook and Twitter to engage visitors and drive traffic. It would employ search engine optimization and pay-per-click advertising to increase awareness and reach more potential readers interested in the topic.
Fish breeding by dr chris andrews
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against developing mental illness and improve symptoms for those who already suffer from conditions like anxiety and depression.
Biological process that effect fish stock
1. The document discusses four biological processes that affect fish stocks: reproduction, growth, recruitment, and mortality.
2. Reproduction can be asexual or sexual, with most fish undergoing external fertilization. Environmental factors, growth, age, food/nutrients, health, and availability of partners can impact reproduction. Manipulating river speeds/temperatures, adding fish ladders, and habitat complexity can help.
3. Growth increases fish size over time through tissue addition and is affected by food availability and environmental factors like temperature. Manipulations include adding fertilizer or protecting nursery areas.
4. Recruitment adds fish to stocks for the first time, and is manipulated through stocking programs and protecting nursery
Behavioural ecology of fishes
This document outlines various behaviors studied in behavioral ecology, including feeding behavior, predation, parasitism, mutualism, and communication. It discusses how feeding behavior is regulated by environmental and homeostatic factors. Predation behaviors in different fish species are described, as well as how predators and prey can control each other's populations. Competition between species and intraspecific competition are examined, including examples of resource partitioning and differential exploitation. The document also summarizes symbiotic relationships like mutualism, commensalism, and parasitism in fish, and covers behaviors like migration, schooling, camouflage, and sound/chemical communication.
Fish
This document provides information about the history and anatomy of fish. It discusses:
- The earliest fish, ostracoderms, from 425 million years ago that lacked jaws.
- Two groups of jawed fish that evolved around 395 million years ago: placoderms with fused upper jaws and acanthodians with bony spines.
- The general characteristics of modern fish, including being cold-blooded, breathing with gills, and moving with fins to maintain salt and water levels.
- The external anatomy of fish including fins, scales, eyes, mouth and lateral line sensory system.
- The internal organs of fish such as gills, heart, liver, kidneys and swim bladder that aid
Acta semanal de desempeño N#1.
Este documento es una acta de desempeño de un equipo de estudiantes de informática. Resume la asistencia, los proyectos trabajados durante la clase como un vehículo solar y juegos mentales, y evalúa el desempeño del equipo con 4 puntos. También identifica algunas dificultades como falta de disciplina y comprensión, e indica que se debe mejorar la escucha.
Quantum-inspired artificial fish swarm algorithm based on the Bloch sphere se...
To enhance the performance of the intelligent optimization algorithm, a new model of performing search on the Bloch sphere is proposed. Then, by integrating the model into the artificial fish swarm optimization, we present a quantum-inspired artificial fish swarm optimization algorithm. In proposed method, the fishes are encoded with the qubits described on the Bloch sphere. The vector product theory is adopted to establish the axis of rotation, and the Pauli matrices are used to construct the rotation matrices. The four fish behaviors, such as moving, tracking, capturing, aggregating, are achieved by rotating the current qubit about the rotation axis to the target qubit on the Bloch sphere. The Bloch coordinates of qubit can be obtained by measuring with the Pauli matrices, and the optimization solutions can be presented through the solution space transformation. The highlight advantages of this method are the ability to simultaneously adjust two parameters of a qubit and automatically achieve the best match between two adjustment quantities, which may accelerate the optimization process. The experimental results show that the proposed method obviously outperforms the classical one in convergence speed and achieves better levels for some benchmark functions.
Fish Pituitary Gland
The fish pituitary gland is located in the brain and has two parts - the glandular and nervous parts. It can be collected through dissection by removing part of the scalp or through the foramen magnum. The gland is then preserved in alcohol or acetone and stored. For injection, it is homogenized in water or saline, centrifuged, and the supernatant is used. Females receive two injections of the extract 6 hours apart at specific dosage levels based on the fish species.
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The Aqua-vision concept of organic carp and backyard fish farming
The Aqua-vision concept of organic carp and backyard fish farming
Quantum-inspired artificial fish swarm algorithm based on the Bloch sphere se...
Quantum-inspired artificial fish swarm algorithm based on the Bloch sphere se...
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Food and feeding in fishes
- 1. Jayachandran PR FOOD AND FEEDIG IN FISHES
- 2. DETRITUS BENTHOSNEKTON PLANKTON Based on niches Hutchinson 1967: • Rhizobenthos • Hyperbenthos • Psammon • Haptobenthos or periphyton • Endobenthos (boring) NATURAL FOOD OF FISHES Phytobenthos Zoobenthos Settled detritus Suspended Pseudo plankton Euplankton Phyto plankton Zoo plankton Epifauna Infauna
- 3. Ecologically /water body (Jhingran,1983) 1. Heleoplankton (pond) 2. Limnoplankton (lake) 3. Rheoplankton or Potamoplankton (running water) 4. Hypalmyroplankton (brackish ) 5. Halioplankton (marine) Meroplankton Zoo plankton Phyto plankton Holoplankton Omori and Ikeda (1984) Net plankton • Megaloplankton –>20 mm, jellyfish • Micronekton –20–200 mm, euphausids • Macroplankton –2–20 mm, copepods • Mesoplankton –200 µm–2 mm, cladocerans Water bottle plankton • Microplankton –20-200µm, copepod nauplii, most phyto • Nanoplankton –2–20 µm,fungi, small diatoms, • Ultraplankton or picoplankton – <2 µm, Mainly bacteria and cyanobacteria,. Bacillariophyceae Dinophycea Cynophyceae Chlorophyceae
- 5. TYPES OF FEEDING (Schaperclaus, 1933) Occasional food Emergency food Main and Natural food Nikolsky(1963) Basic food Secondary food Incidental food Obligatory food
- 6. Based on amount of food Monophagic Eury phagicStenophagic Surface feeders eg. Catla Marginal feeders eg. Rohu Bottom feeders Eg. Mrigal Mid feeders (cloumn feeder) nagendram fish (Osteochilus thomassi) Based on trophic niche
- 7. Moitra 1963 Carnivorous Omnivorous Herbivorous Planktophagus Detritophagus Herbi -omnivore Carni -omnivore Insectivorous Carciniphagus Malacophagus Piscivorous Larvivorous Cannibilistic
- 8. • Relative Gut Length(RGL)(𝐴𝑙 − 𝐻𝑢𝑠𝑠𝑎𝑖𝑛𝑦, 1949) = 𝑳𝒆𝒏𝒈𝒉𝒕𝒉 𝒐𝒇 𝒕𝒉𝒆 𝒈𝒖𝒕 𝑻𝒐𝒕𝒂𝒍 𝒃𝒐𝒅𝒚 𝒍𝒆𝒏𝒈𝒕𝒉 • Index of fullnes (Shorying,1952)= 𝒘 𝑿 𝟏𝟎 𝟒 𝑾 W=weight of gut content, W = weight of the fish • Gastro somatic Index (GSI) (Desai, 1970) = 𝑾𝒆𝒊𝒈𝒉𝒕 𝒐𝒇 𝒕𝒉𝒆 𝒈𝒖𝒕 𝑻𝒐𝒕𝒂𝒍 𝒘𝒆𝒊𝒈𝒉𝒕 𝒐𝒇 𝒕𝒉𝒆 𝒇𝒊𝒔𝒉 • Rate of digestion: (Expressed as no. Hours taken for digestion) 1. Direct method 2. X-ray method(for piscivorous)
- 9. 1. Numeric- Occurrence method (Presence/absence), Number method (%), Dominance method, Point (numerical)method, 2. Volumetric- Eye estimation, Point (volumetric ) method, Displacement method 3. Gravimetric- QUANTITATIVE AND QUALITATIVE ANALYSIS OF GUT CONTENT
- 10. • Forage ratio and food selectivity indices • Index of preponderance • Index of relative importance (IRI) Srivastava, 1985 = (n+v)f n & v - numerical and volumetric % of food, f - frequency of occurrence in % Forage ratio= % food make total stomach % total population food in environment FR=1, selected random, FR= <1, unavail/not selected, FR=>1 food selected /easily avail STRUCTURAL MODIFICATION IN RELATION TO FEEDING HABIT
- 11. Thank you