Development of conditioned reflexes in aquarium fish. Do our freshwater fish feel pain? Conditioned reflex activity of fish

When studying fish, much attention is paid to the development of the concept of “reflex”; for the first time, a definition of the concept of “conditioned reflex” is given. It is important that students become convinced that fish develop a wide variety of reflexes and that they can be developed themselves.

The most accessible include experiments in the production of food conditioned reflexes to sound, light and other stimuli. Relatively quickly (in a week or two) you can train the fish to swim to a certain feeding place in response to signals such as tapping on the glass of the aquarium with a metal object (key, paper clip, coin), or turning on a flashlight light bulb.

During the lesson, when introducing the nervous system and behavior of fish, the teacher can ask students who have aquariums at home to say what conditioned reflexes the kept fish developed on their own, and under what conditions they could have developed. Next, several students can be asked to develop a conditioned reflex to sound and tell how this work should be done.

Equipment and facilities. An aquarium with several fish of the same or different species; flashlight; light bulbs with reflectors; blue and red dyes.

Conducting the experiment. 1. Before conducting an experiment to develop a conditioned reflex to sound, fish must be left without food for several days. Then, before each feeding, you should knock on the wall of the aquarium with a coin or other metal object and, observing the behavior of the fish, give them a little food. The experiment is carried out daily. After the fish eat the food, they are given another small portion by tapping it on the wall of the aquarium.

The fish should be fed in the same place. The time between the action of the conditioned stimulus and its reinforcement with each feeding should be gradually increased. A conditioned reflex is considered developed when fish, after a signal, gather at the feeding site in the absence of food there.

Students should know that the developed reaction to a conditioned stimulus is maintained only if it is reinforced with food or another unconditioned stimulus.

2. In approximately the same way as in response to sound, a conditioned reflex to light is developed. The outside walls of the aquarium are reinforced with a light bulb from a flashlight. To prevent light from spreading in all directions, you can make a small reflector - a cone from a piece of foil glued to thick paper. The light bulb is connected to the battery by wires.

Before the experiment, the fish were not fed for 1-2 days. Students are asked to turn on the light, observe how the fish behave, and then give them some food. The experiment is repeated several times a day. At the same time, it is noted how the behavior of the fish changes, how many days later they will swim to the feeding place immediately after the light signal.

You can suggest the following experience. One small crucian carp is placed in two aquariums or jars with water and aquatic plants. After tapping on the wall of the aquarium, one fish is fed with food falling to the bottom (enchytraea worms, tubifex, bloodworms, small or cut earthworms), the other is fed with food floating on the surface (dry daphnia, gammarus, dry bloodworms). Each tap on the wall of the aquarium is accompanied by feeding.

During the experiment, it is determined after how many days (or, even better, after how many sessions of feeding and signal action) when crucian carp are placed in a common aquarium, one of them will go down while tapping, and the other will go up.

3. An interesting experiment is to determine the ability of fish to respond to colors. Two light bulbs with reflectors are mounted on the outer wall of the aquarium. One of the light bulbs is pre-painted red, the other blue. First, fish develop a conditioned reflex to a red light bulb. Then the blue and red lights are turned on alternately, and no food is given when the blue light is on. At first, the fish react to both lights, and then only to the red one. When the blue light turns on, braking is applied.

During the experiments, students can observe whether conditioned reflexes are developed equally quickly in different species of fish, for example, guppies or swordtails.

Conclusions. 1. Fish form conditioned reflexes to various sounds, light, colors, feeding place. 2. Conditioned reflexes are developed somewhat faster in predatory fish compared to peaceful ones. 3. Educated conditioned reflexes help them to better survive in a changed environment.

Reports on the results of experiments on the development of conditioned reflexes in fish are heard during a lesson on studying nervous system and fish behavior when students were given pre-work assignments when completing their study of arthropods. If schoolchildren showed interest in carrying out the described experiments while familiarizing them with the nervous system and behavior of fish, then the results of work on the development of conditioned reflexes in fish can be obtained for a lesson in which the nervous system and behavior of the frog as a representative of amphibians are considered.

Questions. How do conditioned reflexes differ from unconditioned reflexes? Why are conditioned reflexes formed under the condition of the simultaneous action of an unconditioned reflex? What is the importance of developing conditioned reflexes? What is the significance of the extinction of conditioned reflexes in the absence of their reinforcement by unconditioned stimuli?

Zaletova V.D. 1

Tavchenkova O.N. 1

1 Municipal autonomous educational institution "Secondary secondary school No. 5 of Chelyabinsk", MAOU "Secondary school No. 5 of Chelyabinsk"

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Introduction

Many people are mistaken in thinking that fish are stupid and unresponsive creatures. Indeed, some people initially purchase an aquarium as a purely decorative item. However, observing fish, many aquarists come to the conclusion that fish are not just interior decoration, they are living creatures, interesting in their behavior. Relevance work is that the experiment on the development of a conditioned reflex in aquarium fish teaches us to be attentive to the living beings that inhabit the world around us, helps us to establish ways of interaction with living organisms. This knowledge, in turn, gives us the opportunity to make the living environment more comfortable and respond to the needs of those whose lives depend on our behavior.

Target work: to study the development of a conditioned reflex in different types of aquarium fish.

Object research: aquarium fish.

Item research: conditioned reflexes in fish.

Hypothesis research: suppose that with the help of the knowledge obtained during the experiment, it is possible to develop conditioned reflexes of fish.

In accordance with the goal and hypothesis, the following tasks:

study the behavior of fish, their conditioned and unconditioned reflexes;

identify and describe the fish that live in my aquarium;

conduct experiments on the development of conditioned reflexes in fish.

The following were used in this work: methods research: study scientific literature and Internet materials, description, observation, analysis.

Theoretical significance The work lies in the fact that its results can be presented in lessons about the surrounding world when studying fish.

We believe that the results of the study have practical significance- assistance in organizing the most comfortable habitat for aquarium fish.

Fish behavior. Conditioned and unconditioned reflexes

Fish are vertebrates that live in water. The living conditions of fish and their behavior are interconnected. Each species of fish has innate and acquired reactions to the world around us. The level of development of these reactions is determined by the degree of development in the process of evolution of the senses and central nervous system.

The activity of all body organs in fish and the body as a whole is regulated by the nervous system. It consists of nervous tissue, the brain and spinal cord.

The fish brain consists of the olfactory parts, the forebrain hemispheres, the diencephalon with the pituitary gland, the visual parts (midbrain), the cerebellum and the elongated brain.

Fish have a well-developed memory; they can remember their owners and distinguish them from other people.

Vision is of great importance in the life and behavior of fish. Surely everyone has noticed that when you bring food, the fish immediately perk up and follow the movement of your hand. The cornea of ​​the fish's eye is slightly convex, the lens is spherical, and there are no eyelids. The pupil is unable to contract and enlarge. Due to the contraction of the muscles of the falciform process, the lens of the eye can move back, thus achieving adaptation and adjustment of the vision of fish. Fish are distinguished by the brightness of light and select the most optimal zones for a given species. Most fish see the tone of the object.

The olfactory organs of fish are located in the nostrils, which are simple depressions with a mucous membrane penetrated by branching nerves coming from the olfactory part of the brain. With the help of signals coming through the nostrils, the fish can capture the aroma of food or an enemy at a fairly decent distance.

The taste organs of fish are represented by taste buds. It is curious that in most types of fish papillae are located not only in the mouth, but also on the antennae, head and sides of the body, right up to the caudal peduncle.

Many fish have a well-developed sense of touch, this is especially true for most bottom fish and inhabitants muddy water. The antennae of fish are their organs of touch. With their antennae, fish feel various objects and animals, detect food, and navigate the area.

Fish do not have an external ear. The hearing organs are represented by the inner ear. The inner ear consists of three semicircular canals with ampoules, an oval sac, and a round sac with a projection (lagena). Sounds enable fish to navigate the waters, detect food, escape from opponents, and attract individuals of the opposite sex.

Despite the famous saying, fish are not that dumb. Of course, it is unlikely that fish will be able to please us with melodic harmonies. A person can clearly hear the sounds made by some fish at a great distance. Sounds vary in pitch and intensity. Typically, fish use sound signals during the breeding season.

The skin of the lateral surface contains a unique sensory organ - the lateral line. Typically, the lateral line is a system of depressions or channels in the scalp and body with nerve endings in the depths. The entire system is connected by nerves to the inner ear. It is designed to perceive low-frequency vibrations, which makes it possible to detect moving objects. Thanks to the line, the fish acquires data about the flow and direction of the water, its chemical composition, pressure, “feels” infrasounds.

Pisces exchange data and do this using a variety of signals: sound, visual, electrical and others. For fish that live in schools, interaction is necessary: ​​it can help discover food, escape from predators, select a mate, and carry out other matters that are important to the fish.

Types of aquarium fish to observe

Guppy(lat. Poecilia reticulata) - freshwater viviparous fish. The size of males is 1.5-4 cm; slim; purebred individuals often have long fins; the color is often bright. The size of females is 2.8-7 cm; fins are always proportionally smaller than those of males; females from natural places habitats and many species are gray with a pronounced rhombic mesh of scales, for which the species received its name: reticulum from lat. - mesh, mesh.

The most popular and unpretentious aquarium fish. In a home aquarium, it inhabits all layers. In captivity, it lives longer and grows larger than in nature. Aquariums most often contain various breeds guppies or the result of their mixing.

Very peaceful and able to get along with different types fish It is only important to take into account the impossibility of guppies living alone for a long time. Therefore, these fish must be placed in the aquarium in pairs or groups. The optimal constant water temperature is the range of +24-26 °C.

Guppies are unpretentious, but they can reach maximum flowering only under favorable conditions. The offspring of the most thoroughbred parents in poor conditions will not achieve either their brightness or their luxuriance of fins. Guppies can live in a glass of water, but this is more of an existence than a life.

Sumatran aquarium fish barb(lat. Puntius tetrazona, and formerly Barbus tetrazona), this is a bright and active fish that will enliven any biotope. This is a small fish, with a yellowish-red body and black stripes, for which English it even received the name tiger barb.

It is easy to maintain and is great for aquarists of all levels. They are quite hardy, provided the water is clean and the aquarium is in balance. In an aquarium with Sumatran barbs, it is better to plant a lot of plants, but it is important that there are also free space for swimming. However, they can nibble on tender shoots of plants, although they do this quite rarely. Apparently, there is not enough plant food in the diet.

The Sumatran barb has a tall, rounded body with a pointed head. These are small fish, in nature they grow up to 7 cm, in an aquarium they are somewhat smaller. With good care they live up to 6 years. The body color is yellowish-red, with very noticeable black stripes. The fins are colored red. Also at this time their muzzle turns red.

They eat all types of live, frozen or artificial food. It is advisable to feed him the most varied food to maintain the activity and health of the immune system. For example, the basis of the diet can be high-quality flakes, and additionally provide live food - bloodworms, tubifex, brine shrimp and coretra. It is also advisable to add flakes containing spriulina, as they can spoil the plants.

Aquarium fish neon blue or ordinary (lat. Paracheirodon innesi) has long been known and very popular. With its appearance in 1930, it created a sensation and has not lost its popularity to this day. A flock of blue neons in an aquarium creates a mesmerizing view that will not leave you indifferent. These are the factors that made it so popular.

Neons feel most comfortable in a flock of 6 or more individuals; it is in this group that the brightest colors are revealed. Neons are very peaceful and welcome inhabitants community aquariums, but they need to be kept only with small and equally peaceful fish. Small size and peaceful disposition, good helpers against predatory fish!

Neon is distinguished primarily by a bright blue stripe running across the entire body, which makes it very noticeable. And in contrast to it, there is a bright red stripe, which starts from the middle of the body and goes to the tail, slightly extending onto it.

The blue neons themselves are wonderful and peaceful fish. They never bother anyone, they get along with any peaceful fish. But they can become victims of other fish, especially if it is a large and predatory fish such as swordmouth or green tetradon. Can be kept with large, but not predatory fish, for example, angelfish. What fish do neons get along with? With guppies, platies, cardinals, swordtails, rainbows, barbs and tetras.

Betta fish or cockerel(lat. Betta splendens), unpretentious, beautiful, but can kill the female and other males. It is a typical labyrinth fish, meaning it can breathe atmospheric oxygen. It was the aquarium betta, and even its relative, the macropod, that were one of the first aquarium fish that were brought to Europe from Asia. But long before this moment, betta fish were already bred in Thailand and Malaysia.

The fish gained popularity for its luxurious appearance, interesting behavior and the ability to live in small aquariums. It is also easy to breed and just as easy to cross, resulting in many color variations, different in everything from color to fin shape.

The Betta is simply great for beginners and those aquarists who cannot afford a large aquarium. He needs the bare minimum, both in volume and nutrition. It is also unpretentious, strong, and is always on sale. Due to its labyrinthine apparatus, it can survive in water poor in oxygen and in very small aquariums.

It is very easy to distinguish males from females in bettas. The male is larger, brighter colored, and has larger fins. Females are paler, smaller, have small fins, and their abdomen is noticeably rounder. In addition, she behaves modestly, trying to stay in secluded corners and not catch the eye of the male.

Development of conditioned reflexes in aquarium fish

In the development of conditioned reflexes, fish belong to the most primitive vertebrates. However, various members of this class provide us with remarkable examples of complex behaviors that are worth exploring.

In response to various environmental stimuli perceived by the senses, fish respond with a rather limited number of motor reactions: they swim up or swim away, dive, grab food with their mouths, avoid obstacles that interfere with swimming, etc. The light stimulus, depending on its brightness and quality composition acts differently on the receptors of the fish's eyes and causes a corresponding nerve impulse, which is transmitted along the sensory nerves to the brain, and from here reflexively rushes along the motor nerves to the skin. The pigment cells located in the skin of fish undergo changes under the influence of nerve impulses. This is what causes a reflex change in body color.

To successfully conduct an experiment on the development of a conditioned reflex, the following requirements must be met:

1. Feed the fish in different times, otherwise a conditioned reflex is developed for a while.

2. The conditioned stimulus (knock, light) should act first.

3. The conditioned stimulus is ahead in time or coincides with the unconditioned stimulus - food (food).

4. The conditioned stimulus and feeding are combined several times.

5. A conditioned reflex is considered developed if the fish, when a conditioned stimulus appears, swim to the place where they receive food.

6. When developing different reflexes, the place of feeding must be changed.

Experiment 1. Development of a conditioned food reflex when a foreign object approaches.

Fish are able to distinguish not only color, but also shape, as well as the size of moving objects. For example, by looking at the tweezers from which fish take food, a conditioned food reflex is developed over time. At first, the fish are frightened by tweezers submerged in water, but, receiving food from it each time, after a while they begin to trustingly swim up to the tweezers, instead of swimming away ( figure 1).

Rice. 1. Feeding with tweezers

This means that the fish have developed a conditioned reflex to tweezers as a stimulus that coincides with the unconditioned stimulus—food. In this case, the tweezers serve as a food signal.

Experience result:

In this experiment, tweezers serve as a food signal. The formed reflex can persist even in the absence of feeding, but without reinforcement with food it begins to slow down and fades away (Table 1).

Table 1

Results of observations of feeding with tweezers

started the experiment on September 18, 2017.

aquarium fish

Conclusion: The conditioned reflex is developed on the basis of the unconditioned, having a leading influence of the conditioned stimulus - tweezers. In the fish brain, a temporary connection is established between the visual and food zones of the cerebral cortex.

In barb fish, the conditioned reflex “Response to tweezers” was developed faster than in other inhabitants of our aquarium. Snails do not react to tweezers.

Experiment 2. Development of a conditioned food reflex “Reaction of fish to sound stimuli.”

As you know, fish have neither an outer nor a middle ear. Their organ of hearing (and balance) is only the inner ear, which is characterized by a relatively simple structure. The endings of the auditory nerve approach the inner ear. The question of whether fish hear or are deaf is for a long time was controversial. Now it can be considered proven that fish perceive sounds, but only if the latter passes through water. Essentially, fish cannot detect sound as air vibrations: for this it would be necessary to have a more complex hearing apparatus (tympanic membrane, auditory ossicles), which in the process of evolution appeared only in amphibians, but is absent in fish. Fish are able to perceive sound vibrations arising in the air in the form of vibrations of water particles if they move under the influence of impacts of air sound waves. Therefore, fish hear differently than land animals. Outside the water, fish become deaf and do not react to even the strongest sounds. We conducted an experiment to develop a conditioned reflex to tapping, accompanying the feeding of fish with light blows hard object about the walls of the aquarium ( figure 2).

Rice. 2. Feeding with tapping

Experience result:

As a result, for about a week, with just tapping (without feeding), the fish swim to the place where they usually received food ( table 2).

Table 2

Results of tapping feeding experiment

started the experiment on September 26, 2017.

aquarium fish	Time for fish to approach food (seconds)

Conclusion: In fish of the barb and neon species, the conditioned reflex “Feeding with tapping” was developed faster than in fish of other species. There is no reaction of feeding with tapping in snails. The fish developed the knocking reflex on the 6th day.

Experiment 3. Development of a conditioned food reflex with a light stimulus.

The development of the eyes, their size and position on the fish’s head are directly dependent on its living conditions. For example, in bottom-dwelling fish that watch the approaching prey from below, the eyes are located on the top of the head (catfish); in fish lying on the bottom on one side, the eyes move to the side of the body that faces upward (flounder). In conditions of deep-sea habitat, where light almost does not penetrate, the visual organs of fish are either reduced or increased in size. In the first case, this is the result of a decrease in visual function, and in the second, it is an increase. With the complete loss of vision in some deep-sea fish, the photosensitivity of their skin increases as a compensatory adaptation to orientation in the specific conditions of a dimly lit zone of a reservoir. Same biological significance In some cases, deep-sea fish develop luminous organs, although their role does not end there. It should be noted that fish have a positive reaction to light. They swim to places that are well lit by the sun. Their natural food is concentrated here - numerous small crustaceans that feed on phytoplankton (free-floating algae, the life of which depends on solar radiation). Since plankton, as an unconditional food stimulus, acted on fish every time in combination with sunlight, then the latter received the meaning of a food signal in their life ( figure 3) .

Rice. 3. Feeding with a light stimulus

We conducted an experiment on feeding fish in the presence of a light stimulus: every time we fed, we turned on the light in the aquarium.

Experience result:

One must think that at first the fish developed a conditioned food reflex to light, but over time, repeating itself many times over a number of generations, this reflex was inherited and turned into an innate biologically useful reaction - phototaxis, which became a means for fish to find food. This phototaxis lately successfully used in fishing, attracting fish with the help of electric lamps and other light sources. Commercial exploration using light also gives good results. In this case, a person controls the historically established instinct of fish (the desire for light) in his own interests to the detriment of their life, which indicates relative character expediency of innate reactions ( table 3).

Table 3

Results of feeding experiment with light stimulus

started the experiment on 10/01/2017

aquarium fish	Time for fish to approach food (seconds)

Conclusion: Barb and betta fish react to light faster than other fish. There is no reaction to feeding with light in snails, a weak reaction in guppies.

Conclusion

As a result of the work done, it turned out that the aquarium - small world ok, which provides a unique opportunity to bring a piece of nature into your home, where everything is coordinated, lives in harmony, develops, changes, revealing itself to the observer.

In highly organized animals with a central nervous system, there are two groups of reflexes: unconditioned (innate) and conditioned (acquired). Reflexes have an important adaptive value for maintaining the integrity of the body, full functioning and constancy internal environment. Aquarium fish can develop all sorts of conditioned reflexes to various stimuli: time, light, color and shape of objects, etc.

During the experiment, we made the following conclusions.

To develop a conditioned reflex in aquarium fish, certain conditions must be met.

During the experiment, conditioned reflexes were developed in the aquarium fish guppy, barb, neon, and cockerel to sound, light, and feeding from tweezers.

Fish develop a reflex to sound faster than others.

Conditioned reflexes contribute to the adaptation of organisms to environmental conditions (in this case, feeding conditions).

The degree of response and learning ability differ significantly among representatives of different families and even species of aquarium fish. When studying the behavior of fish in an aquarium, the level of adaptation in species such as barb, betta and neon turns out to be high. Aquarium snails have absolutely no reactions to external stimuli.

Tapping on the wall of the aquarium became a stronger stimulus, and therefore the conditioned reflex developed faster.

Thus, the research hypothesis that we can develop conditioned reflexes in fish was confirmed, the goal and objectives of the study were fulfilled.

This paper examines an example of the development of only some conditioned reflexes. The acquired knowledge gives rise to wide range opportunities for scientific knowledge laws of nature and improving one’s own knowledge.

Observing fish, as well as writing a research paper, taught me to independently work with sources of information (books, the Internet), process information, and keep an observation diary. In the future, I would like to continue observing the fish, try to develop new reflexes in them, and learn to understand their needs.

Many people say that keeping fish is not fun because they cannot be trained. But training is based on the development of a conditioned reflex. And my observations of fish confirmed that they can develop conditioned reflexes.

Bibliography

Ziper, A.F. Control of the behavior of animals and birds. Reflexes in the life of animals [Text]. - Access mode: http://fermer02.ru/animal/296-refleksy-v-zhizni-zhivotnykh.html

Pleshakov, A.A. From earth to sky. Atlas-identifier: book. for beginning students class [Text] / A.A. Pleshakov. - M.: Education, 2016. - 244 p.

Rules for the development of conditioned reflexes [Text]. - Access mode: http://www.medicinform.net/human/fisiology8_1.htm

Sereev, B.F. Entertaining physiology [Text] / B.F. Sergeev. - M.: Bustard, 2004. - 135 p.

I explore the world: Children's encyclopedia: Animals [Text, drawing]. - M.: LLC "AST Publishing House", 2001. - 223 p.

The exploratory reflex, or the “What is this?” reflex also helps animals avoid danger.

What is its essence?

Every animal, finding itself in an unfamiliar environment or seeing an unfamiliar object, looks closely, listens, and sniffs, trying to determine whether it is in any danger. But without approaching an unfamiliar object, you won’t know what to expect from it. And the animal, overcoming fear, tries to figure out the situation.

It was precisely taking this animal instinct into account that Main-Read, in one of his novels, spoke about next case. The hunter was running out of food, and he still had a long way to go across the prairies. At dawn he spotted a herd of antelope. How to get close to watchful animals if there is not a single shelter around? And the hunter found a way out. Approaching the antelopes at such a distance that they noticed him, he sank down on his hands and began to make intricate pirouettes in the air with his feet. This unusual sight attracted the attention of the animals, and the antelopes began to slowly approach the hunter. When they were within shooting distance, the hunter jumped up, grabbed his gun from the ground and shot the nearest antelope.

Fish do the same. Every spinning angler has had to watch how fish much smaller than the bait itself rush after the spoon. This is a manifestation of the research reflex. Perhaps so. accumulation of some fish near a submerged fish light bulb is also a manifestation of this instinct.

It is possible that the approach of many fish to sound is explained not by food, but also by an exploratory reflex, which, after the fish has discovered prey, turns into food.

Instincts do not always remain constant. Apparently, salmon once spawned in the ocean. But there were fewer enemies in the rivers, more favorable conditions for the ripening of eggs, and the instinct changed - salmon began to lay eggs in fast-flowing rivers.

Ladoga trout, like salmon, enter rivers to spawn. At the same time, it always rises upstream. But the Ladoga trout, acclimatized in Lake Yanis-Yarvi, descends to spawn in the Yanis-Yoki River, flowing from the lake. The instinct has changed because not a single river with suitable spawning grounds for lake trout flows into Lake Janis-Jarvi.

Not long ago, a fish from the Gulf of Finland rose to spawn in the Narova River and, having spawned, went back to the bay. After the construction of the dam on Narova, part of the Syrti herd was cut off from the bay. Now the raw material has become accustomed to new conditions; it lives and reproduces in the Narova, Velikaya and Lake Peipsi rivers.

However, instincts do not always change when living conditions change. For example, the construction of a power station on the Volkhov River closed the way for whitefish to their favorite spawning grounds and led to their almost complete extinction.

The actions of a given animal, explained by acquired experience, are classified by I. P. Pavlov as conditional. reflex activity. It turns out that, despite the primitive structure of the brain in fish, they develop conditioned reflexes quite quickly. Scientists have done many interesting experiments with fish. They are easy to replicate for anyone with an aquarium.

Hang a red bead on a thread in the aquarium - and the fish will definitely “try” it. At the same time, throw the fish's favorite food into the stern corner. Repeat the experiment several times, and after a while the fish, tugging at the bead, will rush to the stern corner, even if they are not offered food. Replace the red bead with a green one, but do not feed the fish. The fish won't touch it. But you can retrain the fish - make them grab the green bead and refuse the red one.

Cut out two triangles from cardboard, one large and one small. While feeding the fish, apply one triangle to the glass, and after feeding, another. After some time, the fish will approach the triangle of the same size that was applied to the glass during feeding; will approach even if they are not given food, but will not pay any attention to the second one. The triangles can be replaced with letters of the alphabet, and the fish will soon learn to distinguish between them.

Or one more example. Among the silversides, which live mainly in tropical waters, there are fish that are bright red and almost colorless. So, pieces of stinging sea anemone tentacles were put into the mouths of red fish and they were put into an aquarium with predatory fish. After predators tried silversides with sea anemone tentacles, they lost all interest in them. Red fish released into the aquarium a few days later, without the “filling,” remained untouched for a long time, while the uncolored silversides were immediately eaten.

A conditioned reflex in fish can also be developed to sound. If you feed fish by calling, then soon they will come to the call even in the absence of food. Moreover, experiments have shown that fish can develop conditioned reflexes to sounds different heights tones. Callicht catfish were fed at one tone of sound, and hit on the nose with a stick at another. After some time, the catfish swam up upon hearing the sound of the first tone, and upon hearing the second tone, they rushed to their heels and hid in the far corner of the aquarium.

The following experience clearly illustrates the importance of acquired skills: an aquarium with a pike in it was partitioned with glass and a live fish was allowed into the partitioned off part. The pike immediately rushed towards the fish, but after hitting the glass several times, it stopped its unsuccessful attempts. When the glass was taken out, the pike, taught by “bitter experience,” no longer resumed attempts to grab the fish.

A fish that has been hooked or grabbed an inedible spoon carefully takes the bait. That is why in remote reservoirs, where the fish is “not familiar” with a person and a fishing rod, it takes the bait more boldly than in reservoirs frequently visited by anglers. For the same reason, where there are many underwater hunters, it is difficult to get close to the fish with a shot from a harpoon gun.

Since the caution of fish is associated with the experience they have acquired, it is natural that the older the fish, the more suspicious it is of all kinds of unfamiliar objects. Watch a school of chub swimming near the bridge abutments. Small chubs are kept closer to the surface, and dark cigar-shaped silhouettes are visible deeper large fish. Throw a grasshopper into the water - a splash - and it disappears into the mouth of one of the large chubs. Now pierce the grasshopper with a straw and throw it into the water again; a large chub will swim up, but won’t take the bait, and only a small one will fiddle with the grasshopper with a straw sticking out of it.

In order for a fish to become wary of rough tackle, it does not necessarily have to be hooked itself. Sharp throws of one fish caught on a hook can frighten and alert the entire flock for a long time, causing a suspicious attitude towards the proposed bait.

Sometimes fish use the experience acquired by their neighbor. In this regard, the behavior of a school of bream surrounded by a seine is characteristic. First, finding themselves in the tone, the fish rush in all directions. But as soon as one of them, taking advantage of the unevenness of the bottom, slips under the bowstring, the whole flock immediately rushes after it.

Now the behavior of the “cunning” perch, driving others away from the hook with the nozzle, is also clear. Obviously, he has already been hooked and is careful not to take the bait, and others follow his example.

Observations of fish in an aquarium confirmed that fish really adopt the experience of their neighbor. The following experiment was carried out. The aquarium was divided in half with a glass partition and several verkhovkas were planted in one half. A red light was lit in the corner of the aquarium, the light of which attracted the fish. When approaching the light bulb, they received an electric shock and fled. After several experiments, the fish scattered as soon as the red light flashed. Then, other aerie verkhovkas were placed in the second part of the aquarium. When the light bulb was turned on, the newly planted fish, following the example of their neighbors, also ran away from the red light, although they had not previously received any electric shock. After ten experiments, the first batch of fish was released, but the remaining ones retained a negative reflex to red light.

Typically, conditioned reflexes in fish do not last long, and they soon forget what they have learned. However, if the conditions under which the reflex arose are repeated from generation to generation, it can become congenital. .

See how the telescope floats in the aquarium. He always turns in some direction, trying to swim in a circle. His penchant for “circular swimming” appeared because in China, the birthplace of telescopes, many generations of these fish were kept in vase aquariums.

In most rivers, chub feed on worms, insects and their larvae, plants, and small fish. But all sorts of things end up in the Neva food waste, and the chub became almost omnivorous in it. Here it is caught with a fishing rod, placing a piece of sausage, cheese or even herring on the hook. In rivers located far from large cities, the chub will not touch such a bait. Thus, a change in nutritional conditions led to the transformation of a temporary food reflex into a permanent one.

As we see, the “intelligence”, “ingenuity” and “cunning” of fish are explained by innate instinct and experience acquired during life.

V. Sabunaev, "Entertaining ichthyology"

Last name, first name of the author of the article Bogdanova Diana Class 5d

OS name Municipal budgetary educational institution Lyceum No. 5 of the city of Yelets, Lipetsk region

Last name, first name, patronymic of the manager Zamury Svetlana Yurievna

Topic:

e-mail: [email protected]

Development of conditioned reflexes in aquarium fish
Nowadays, the vast majority of people, no matter where they live or what they do, have to deal with animals. A resident of a modern city, one way or another, comes into contact with animals, be it fighting cockroaches in the kitchen or communicating and caring for pets.

Last year, for my birthday, my parents gave me an aquarium. I was very happy about this.

Many people say that keeping fish is not fun because they cannot be trained. But training is based on the development of a conditioned reflex. And my observations of fish confirmed that they can develop conditioned reflexes.

Problem: How are conditioned and unconditioned reflexes related?

Hypothesis: Aquarium fish can develop a conditioned reflex to any stimulus.

The purpose of my research: To prove that the conditioned reflex in fish is developed on the basis of the unconditioned, having a leading influence of the conditioned stimulus

Research objectives:

1. Study the literature on the topic: “Animal behavior. Conditioned and unconditioned reflexes";

2. Identify and describe the fish that live in my aquarium.

3. Conduct experiments on the development of conditioned reflexes in animals.

4. Find out to which stimulus the conditioned reflex is developed faster.

Object of study: aquarium fish

Subject of research: conditioned reflexes in animals

In my work I used the following research methods:

Studying scientific literature on the topic “Conditioned and unconditioned reflexes”; Description of aquarium fish; An experiment on the development of conditioned reflexes to various stimuli.

Unconditioned and conditioned reflexes.

Unconditioned reflexes- hereditarily transmitted (congenital) reactions of the body, inherent in the entire species.

Conditioned reflex- This is the body’s reaction to a stimulus developed during development.

Unconditioned reflexes are the main innate foundation in the behavior of an animal, which ensures (in the first days after birth, with the constant care of parents) the possibility of the normal existence of the animal. However, as the animal develops, it acquires more and more more individually acquired acts of behavior. These are conditioned reflexes.

Conditions for the formation of conditioned reflexes.

The first condition for the formation of a conditioned reflex is the coincidence in time of the action of a previously indifferent stimulus with the action of some unconditioned stimulus that causes a certain unconditioned reflex.

The second condition for the formation of a conditioned reflex is that the stimulus that turns into a conditioned reflex must somewhat precede the action of the unconditioned stimulus.

When training an animal, commands and gestures should be given somewhat earlier than the unconditioned reflex stimulus begins to act. For example, when training a dog to walk side by side, the verbal command “nearby” should slightly (by 1-2 seconds) precede the jerk of the leash, which causes an unconditional reflex reaction. If the stimulus, which should become a conditioned reflex signal, is given after the unconditioned reflex stimulus, then the conditioned reflex will not be developed.

Therefore, when training animals, it is necessary to strictly ensure that conditioned signals slightly precede the action of the unconditioned stimulus.

The third extremely important condition for the formation of a conditioned reflex is that the hemispheres of the animal’s brain must be free from other types of activity during the development of the conditioned reflex.

When developing conditioned reflexes, one must try to exclude, as far as possible, the influence of various extraneous stimuli. Fourth condition the formation of conditioned reflexes is the strength of the conditioned stimulus. Conditioned reflexes to weak conditioned stimuli are developed slowly and are of smaller magnitude than to strong stimuli. However, it must be borne in mind that excessively strong conditioned reflex stimulation can cause in some dogs (especially those with a weak type of nervous activity) not an improvement, but, on the contrary, a deterioration in their conditioned reflex activity. And in some cases, the conditioned reflex may not be developed at all.

It is also necessary to keep in mind that the strength of the unconditioned stimulus during the development of a conditioned reflex should be greater than the strength of the conditioned stimulus, since a conditioned stimulus of great strength (for example, a strong sound, a shout, etc.) can inhibit the manifestation of the unconditioned reflex in the animal ( for example, food).

The fifth condition for the formation of conditioned reflexes is the state of the unconditioned reflex on the basis of which the conditioned reflex is developed. During the development of a conditioned reflex, the unconditioned reflex must be in a sufficiently excitable state. If a conditioned reflex is developed on an unconditioned food reflex, it is necessary that the animal gets hungry; a fed dog will respond weakly to food reinforcement, and the conditioned reflex will be developed slowly.

2. Definition and description of the inhabitants of my aquarium

Parrot(Pelvicachromis pulcher) lives in rivers with brackish water in West Africa . This fish was first brought to Europe in 1951. The parrot has an elongated, laterally compressed body. The profile of the back is curved more than the belly. The front of the head, with a terminal mouth and sloping forehead, is slightly curved downwards and resembles the head of a parrot (hence the name). More often, a wide dark brown stripe runs along the entire body, from the snout to the end of the caudal peduncle. The back is dark. There is a cherry-colored spot on the abdomen, the bottom of the head is golden.

Sumatran barbs(Barbus tetrazona) - peaceful, schooling, very active fish.The body of these barbs is high, strongly compressed laterally. No mustache. The general color is golden-pink, the back is darker with a red tint, and the belly is yellowish-white. There are four vertical black stripes on the sides. The first goes through the eye, the second behind the pectoral fin, the third behind the dorsal fin and the last at the beginning of the caudal fin.

Shark barb(Balantiocheilus melanopterus ) lives in rivers and streams fast current in Thailand and the islands of Southeast Asia: Kalimantan and Sumatra. Appearance The shark ball is discreet, somewhat reminiscent of a roach. It has a narrow, laterally compressed body, large eyes and a lower mouth. There are no mustaches. The main body color is silver-steel. The scales are large, resembling a small mirror (creating a sparkling effect). Pectoral fins colorless. The rest are either transparent or yellowish with a wide black border. Sexual differences: males are slimmer and smaller than females. In young individuals it is almost impossible to distinguish the sex. They reach a length of up to 35 cm. They grow very quickly. Pearl gourami (Trichogaster leeri) . The main background is cream, and the entire body and translucent fins are covered with numerous iridescent light spots, reminiscent of pearls (hence the name). The abdomen of males is blood-red in color, their dorsal fin is pointedly elongated, the anal fin is powerful, with fringed elongated rays. A black stripe runs along the body, starting from the snout and ending at the base of the caudal fin. The fish reaches a length of 11 cm.

Ancistrus dolichopterus) Family Chain catfish (Loricariidae). Ancistrus vulgaris lives in mountain rivers South America in the tributaries of the Amazon, in the Andes in Peru, as well as in the upper reaches of the Orinoco in Venezuela. The body shape of Ancistrus vulgaris is teardrop-flattened, the head is wide. The body is covered with rows of wide bony plates. The main color ranges from light gray yellowish to dark gray and black with light specks. The color is very variable and often ancistrus “turn pale”. Adult male ancistrus can reach up to 10 cm. The mouth of the fish is in the form of a suction cup with elongated lips, equipped with horn-like scrapers that allow you to remove fouling from the walls of the aquarium, snags, and plant leaves.

Danio rerio (Brachydanio rerio) - fish upper layers coastal part of standing and slow-flowing reservoirs of Southeast Asia, usually floating between the stems of aquatic plants and coastal grasses hanging into the water. Here she looks for her prey - small invertebrates. Here fish spawn, scattering eggs in dense thickets of coastal plants. Danio is one of the most common aquarium fish. The fish are very active and unpretentious. They live even in the smallest aquariums. Danio rerio stays mainly in the middle and upper layers of water. When frightened, they can jump out of the water, so the aquarium must be covered with a tight lid. It is preferable to keep zebrafish in a group of 8-10 fish. Observing zebrafish that are fast and graceful in their movements gives aquarium lovers great pleasure

3.Development of conditioned reflexes to various stimuli in fish.

Method of doing the work

Develop a conditioned reflex in fish to three different stimuli: light; bead; tapping on the aquarium.

Experimental conditions: feed the fish at different times, otherwise a conditioned reflex will be developed for time.

Rules for developing conditioned reflexes:

a) the first to act is an indifferent stimulus - light; b) it is ahead in time or coincides with the unconditioned stimulus - food (food); c) light and feeding are combined several times; d) when the light is turned on, the fish swim to the walls of the aquarium, which means that the indifferent stimulus (bead) begins to cause the same reaction as the unconditioned stimulus (food); e) a conditioned reflex has been developed.

In the same way, I developed a conditioned reflex to other stimuli (a bead, a knock)

Table No. 1 Development of a conditioned reflex to light

Date of observation	Light and feeding time
02.09.2012	08.30	5 minutes
03.09.2012	10.10	4 minutes
04.09.2012	18.30	3 minutes
10.10.2012	21.00	1 minute
12.10.2012	07.20	30 seconds
18.10.2012	19.00	10 seconds	18.10.2012

Conclusion: The conditioned reflex is developed on the basis of the unconditioned, having a leading influence of the conditioned stimulus - light. In the brain, a temporary connection is established between the visual and food zones of the cerebral cortex. Light became the dominant stimulus. The conditioned reflex was developed after 46 days.

Table No. 2 Development of a conditioned reflex to a bead

Date of observation	Bead and feeding time	Time for fish to approach food	Date of development of the conditioned reflex
28.10.2012	08.30	5 minutes
29.10.2012	10.10	4 minutes
30.10.2012	18.30	3 minutes
05.11.2012	21.00	2 minutes
08.11. 2012	07.20	1 minute
10.11.2012	19.30	30 seconds
18.11.2012	20.00	5 seconds	18.11.2012

Conclusion: The conditioned reflex is developed on the basis of the unconditioned one, having a leading influence of the conditioned stimulus - the bead. In the brain, a temporary connection is established between the visual and food zones of the cerebral cortex. The bead became the dominant stimulus. The conditioned reflex is developed after 20 days.

Table No. 2 Development of a conditioned reflex to tapping on the aquarium

Date of observation	Knocking and feeding time	Time for fish to approach food	Date of development of the conditioned reflex
28.11.2012	08.30	5 minutes
29.11.2012	10.10	4 minutes
30.10.2012	18.30	3 minutes
05.12.2012	21.00	1 minutes
08.12. 2012	07.20	30 seconds
10.12.2012	19.30	20 seconds
13.12.2012	20.00	5 seconds	13.11.2012

Conclusion: The conditioned reflex is developed on the basis of the unconditioned, having a leading influence of the conditioned stimulus - knocking. In the brain, a temporary connection is established between the auditory and food zones of the cerebral cortex. The knocking became the dominant irritant. The conditioned reflex is developed after 15 days.

Conclusion

After conducting research, I came to the conclusion: conditioned reflexes in fish are developed on the basis of the unconditioned, having a leading influence of the conditioned stimulus. Aquarium fish can develop a reflex to any stimulus.

Tapping on the wall of the aquarium became a stronger stimulus, and therefore the conditioned reflex developed faster.

During the study, my hypothesis was confirmed.

Observing fish, as well as writing a research paper, taught me to independently work with sources of information (books, the Internet), process information, and keep an observation diary.

During the course of my work, I realized that an aquarium is a unique opportunity to bring a piece of nature into your home, to create your own little world where everything is coordinated, everything lives in harmony, develops, changes, revealing itself to the observer. This fragile world depends entirely on its owner - without constant care and attention it will die.

We must learn to live, giving the opportunity to live to other organisms on our planet. Studying animal behavior will help us understand ourselves.

References

1. Bertron R. Feelings of animals. - M., 1972

2. Sergeev B. From amoeba to gorilla. - L.: Children's literature, 1988.

3. Noga G.S. Observations and experiments in zoology. - M.: Education, 1979

4. Sergeev B. F. Entertaining physiology. - M.: Bustard, 2004.

5. I explore the world: Children's encyclopedia: Animals [text, drawing]. – M.: LLC “AST Publishing House”, 2001 – pp. 221 – 223.

Remote Access Resources

6. Ziper, A. F. Control of the behavior of animals and birds. Reflexes in the life of animals [text]. – Access mode.

Conditioned reflexes of fish. The continuous neural tube of vertebrates creates the most favorable conditions for communication of all parts of the nervous system. Its leading department, the brain, concentrates the functions of controlling behavior, and in it the structures that carry out conditioned reflexes receive extraordinary development.

Anyone who keeps fish in an aquarium knows how easy it is to teach them to swim to the surface when the owner makes movements with his fingers, which are usually used to pour a pinch of food into the water. The sight of a person's hand approaching the surface of the water, which previously caused a defensive reaction of flight, now becomes a signal of a conditioned food reflex. Aquarium fish can develop a variety of conditioned food reflexes, for example, to lighting a certain place in the aquarium, accompanied by feeding in this place, to tapping on the wall of the aquarium, if accompanied by feeding, etc.

In the natural environment, the ability to develop new behavioral skills helps fish adapt to changing living conditions.

The new conditioned reflexes that are formed are stronger than many innate instincts and can change them and even completely suppress them. For example, if a predatory pike is placed in the same aquarium with its usual prey - crucian carp, separated by a glass partition, then the pike begins to rush at the crucian carp. However, after repeated painful blows of its snout against the glass, it stops trying to grab its prey. If you now remove the partition, the pike and crucian carp will calmly “swim” next to each other.

The fact is that fry, bred in artificial conditions at a fish hatchery, when they get into an open reservoir, river or lake, die en masse from predators, since safe life in industrial pools did not give them a reason to develop protective behavior. Increasing the survival rate of fry of valuable species of commercial fish can be achieved by artificially developing in them conditioned defensive reflexes to the sight of predatory fish.

To develop such reflexes, a stuffed animal, reproducing the figure of a predator fish, was lowered into a pool with fry and passed through the water electric current or hit its surface. After a number of such combinations, only the appearance of the figure of a predator caused the fry to flee. The practical significance of this method of increasing the productivity of fish farming can be judged from the results of an experiment conducted in one of pond farms Karelia. A pre-calculated number of fry of a valuable fish and one predator, a chub, were released into a fenced area of ​​the pond. After 1-2 days, we counted how many fry survived.

It is known that amateur fishermen, in order to ensure good catches in their favorite gestures, especially in quiet backwaters, systematically bring and throw into the water scraps and everything that can be edible for fish. It is possible that in this way the fish develop conditioned food reflexes that attract them to the feeding site. Recently, information has emerged that some coastal fisheries feed fish in certain places in order to increase their catch.

Conditioned reflexes of birds. The everyday observation that “a crow is afraid of a bush” indicates a good ability to develop conditioned reflexes. Birds have this ability already at an early age. For example, chickens quickly imitate a pecking hen, and rhythmic tapping becomes a signal for them to peck at the food. This way you can encourage feeding activity in weak chickens.

Cases are described in which chickens, hunting for flies, grabbed a wasp or a bee and, once stung, made no more mistakes. Other observations have shown that chickens quickly learn to distinguish edible from inedible caterpillars by shape and color. If chickens are fed only by hand, then they stop responding to the clucking of the chicken and run after their breadwinner squeaking.

Week-old chicks can develop a variety of food and defensive conditioned reflexes to light, sound and other signals. However, fine discrimination of these signals is achieved only at the age of 2-3 weeks. Adult chickens quickly adapt to the daily routine in the chicken coop and gather at the feeders exactly at the feeding hours.

Since the main signal for chicken activity is light.

Even more theoretically and practically interesting results were obtained in experiments with the transformation of one natural day into two artificial ones. To do this, lighting and darkening were alternated in the poultry house during each day in the following order: 0-4 hours - normal night, from 4 to 12 hours - light day, from 12 to 16 hours - darkening, creating a “second night”, after which For 16 to 24 hours deep into the night, artificial lighting maintained the atmosphere of a bright “second day.” The chickens raised under these conditions learned the new regime and in two “days of light” during the day they managed to eat more food, gain more live weight, and many of them began to lay eggs twice a day. As a result, the productivity of chickens has increased markedly.

Young birds learn to find their way to their nest, primarily by visual cues. They circle over it for a long time, memorizing characteristic features surrounding landscape. The ability of pigeons to return home even from afar has been used since ancient times in the form of pigeon mail. Pigeon mail has not lost its importance to this day, especially in military affairs: it lacks the main disadvantage of radio communications, in which messages are easily intercepted, and the location of the transmitter is accurately determined by direction finding. About a million carrier pigeons took part in the First World War. In the Second World War, the British air force alone had several tens of thousands of carrier pigeons in service.

Conditioned reflexes of rodents. The house mouse learns, using complex tricks, to obtain food for itself and to escape from the dangers that await it at every step as a result of persecution by humans, cats, etc. The life of mice and rats in the winding paths of the underground has developed in them the ability to quickly navigate them and remember everything inputs and outputs. Therefore, various experiments on the psychology of learning are carried out on laboratory white rats, measuring the time required to find a way out of confusing roads and a labyrinth.

To study the properties of higher nervous activity in mice, rats, and rabbits, they develop conditioned reflexes to light, sound, olfactory and other signals in special chambers. If a food reflex is developed, then the feeder opens upon a signal, and if a defensive reflex is developed, then an electric current is connected to the metal floor grate. In this way, the properties of conditioned reflexes and their changes under various influences on the animal’s body are studied ( physical work, medicines, hunger, etc.).

The peculiarities of the lifestyle of mice and rats in the dark corners of the underground are reflected in the fact that they form conditioned reflexes to sound signals much more easily than to visual signals. However, they also develop visual conditioned reflexes well. This can be used to show the effective experience of "putting mice on a train." If some of the white tame rats or mice are marked with red paint and fed only in red carriages, and the rest - in white ones, then when the train arrives they will scatter to “their” carriages,

The behavior of beavers, known for their valuable fur. With amazing skill they build dams that raise the water level in the river. (It is known that beavers’ homes have an underwater entrance.) At the same time, old beavers teach young beavers the most effective techniques for gnawing and felling trees, cutting them up, floating them to the construction site and laying them in the body of the dam. All these works are carried out unanimously by all members of the colony under the leadership of the leaders. The "language" of beavers is interesting. They call each other out of their homes by whistling, exchange guttural sounds when felling trees, etc. Depending on local conditions, the size of the river, the condition of the banks and other circumstances, beavers choose different methods and means of construction, erecting complex hydraulic structures. Conditioned reflexes of ungulates. In pigs from the very early age a variety of conditioned reflexes can be developed. This is used, for example, to collect piglets after a walk. It is enough for the pig farm to give a certain signal for several days before each feeding (hitting the bottom of the bucket like a drum), and at this signal the piglets will run together to the feeders from all over the pen.

Sheep and goats develop complex food conditioned reflexes that have been studied both in the laboratory and in natural conditions. The secretion of saliva in sheep that were transferred from confinement to grazing was studied.

In the first two days, neither the path to the pasture, nor even the proximity to grazing sheep caused salivation in the experimental sheep. On the third day, her mouth watered at the sight of grazing sheep. Then conditioned reflexes were formed to the sight of the pasture, the road to it, and after two months it was enough to take the sheep out of the stall into the corridor, and it would already begin to salivate.

Based on signals from the natural environment, sheep develop adaptive conditioned reflexes that cause changes in metabolism in the body. The sight of wind-bending grass increases heat production, while bright sunlight reduces heat production. This regulation of metabolism allows the sheep to tolerate and winter snowstorms, and summer heat in an open field.

Of great importance for increasing the milk yield of cows are the conditioned reflexes of milk production and milk yield, which are developed in them by the conditions of housing and milking. A certain daily routine constant time milking, the same milkmaid becomes signals that reflexively excite the mammary glands in advance. Anything that interferes with the manifestation of this reflex - noise and disorder, rough handling of the cow, untimely milking, frequent changes of milkmaids - leads to a decrease in milk yield even in highly productive cows. The practice of advanced dairy farms has shown that the use of conditioned reflex factors can be an effective means of increasing milk production.

As a result of centuries-old experience of domestication and economic use, a person uses a whole complex of signals to control its behavior. Well-known verbal commands are reinforced by musculocutaneous irritations through the reins and whip for a draft horse, reins, leg (the inner part of the rider's shin facing the horse) and spurs for a riding horse. In circus training, music is often used as signals for the horse's movements, to the rhythm of which the horse "dances".

The horse has a keen sense of hearing and smell, and is well versed in the terrain. Therefore, if you get lost, for example, in a snowstorm, you can let her find her way by the smell of a home brought from afar or the sounds of barking dogs that are inaudible to us.

In our country, serious work is underway to domesticate the inhabitant northern forests - mighty moose, which is able to overcome swamps and off-road conditions that are beyond the strength of a horse. However, the most interesting prospects are opening up in the use of moose as dairy animals.