The pattern of growth and ontogeny of the body shape of the word fish (Caspicus Rutilus rutilus) in the early stages of development in the larval rearing period.

Dissertation for M.Sc degree

in the field of fisheries - breeding and breeding of aquatic animals

Abstract

This research is to examine the growth pattern, the process of body shape changes during the early stages and the analysis of the pattern of body structures during the early stages of development and to investigate the role of functional correlation and The efficiency of each of the shape stages of word fish (Rutilus rutilus caspicus) was done. Sampling was done in Vashemir dam sturgeon restoration complex from 0.5 hectare pond which was a natural mesocom for rearing Kalema fish larvae. Sampling started from the moment of hatching, which was done daily in the first 12 days, from day 12 to day 30 with one-day intervals, from day 30 to day 45 with two-day intervals, from day 45 to day 60 with five-day intervals, and from day 60 to day 80 with ten-day intervals. The samples were fixed in 4-10% phosphate-formaldehyde buffer solution. The pictures were taken with a loupe equipped with a 6 megapixel Kodak camera, from the left side. Muzzle length, head length, body length, tail length, total length, eye diameter, body height were extracted from the images using ImageJ version p1.44 software. Geometric shape measurement was done by landmarking method using TpsDign version 2.16 software. At first, the coordinates data of the landmarks were superimposed using GP analysis [1] and shape changes during growth were drawn as a shape change network [2] by Tpsreg software, the correlation between shape variables and total length was examined using correlation test in PAST software. In the principal component analysis, the changes related to the new selected components and the growth trajectory were plotted by plotting the RWA axis (as a descriptor of body shape) against the total length. The average shape of the corresponding network of shape changes for each age group was calculated using TPS Spline software. In order to cluster the body shape between age groups, a cluster analysis was performed using Ward's algorithm, and a multivariate test was performed using transformed and standardized data in order to It was used to check the significance or not of differences in ontogenic traits. The results showed that the growth allometry of all the examined areas of the body of Kalama fish except for the trunk area and the diameter of the eye during the early stages of growth are positive. Changes in growth coefficients also showed three turning points on the third and thirty and forty-first days after hatching. According to multivariable allometric results, body height and snout length had the highest growth coefficient. According to the results of RW, major changes have occurred in the designated areas, i.e. head, trunk and tail. The change process of RW1 to RW2 and PC1 to PC2 shows three shape groups. According to Ward's Euclidean dispersion test[3], four main stages were obtained based on morphological changes during the life of Kalama fish from day 0 to day 80 after hatching. According to the CVA test, there are three groups of shapes that express the change in the shape of the word fish during growth, and the effective traits in this process of change are landmarks y8, y6, and y9 on axis one and x1, x6, x7, x8 on axis two. Landmark 7 is related to the tail area, landmarks 6 and 8 are related to the trunk area, and landmark 9 is related to the head area, which indicates the increase in body height and the change in the shape of the spindle to wide body. Increasing the length of the snout is to make the mouth lower and find an efficient shape for bottom feeding. The shape changes extracted from TPS Spline indicate that the changes of the body landmarks, nine landmarks, we clearly see changes in the head, snout, tail, and body height, so that finally we can easily see the change in shape and the process of becoming a fish with an elongated shape to a fish with a high body height.

1-1- General

Increasing demand for grains, legumes, protein materials, etc., and environmental issues have existed since long ago, and now it has become more intense. However, until a century ago, there were not many actions that would disrupt the natural system of the environment. Ecological transformations increased when the number of human population and its concentration in limited places increased and the level of per capita demand and as a result the need of human societies for natural resources increased. With the emergence and development of industry, then the industrial revolution and the production of various products, the quality of human life improved in an unprecedented way and humans progressed on the way to a better and prosperous life. But the revolution in industry and purpose caused the gradual emergence of problems.But the revolution in industry and purpose caused the gradual appearance of environmental issues and problems. The main source of these issues is the ever-increasing reduction of natural resources and the creation of various types of pollution in the environment. Currently, the per capita demand of people on the planet is much higher than the growth of the production of natural resources, so that the resources and renewable raw materials have decreased or become unavailable day by day. The consumption of fossil fuels has increased compared to the era before the industrial revolution and has caused changes and crises. Excessive and unplanned exploitation of natural ecosystems leads to the destruction of natural resources and ultimately the breakdown of the ecological system. On the other hand, the environment is under the pressure of massive wastes caused by consumables and throwaway materials, which are digested and absorbed by nature's spontaneous purification [1]. But the accumulation and indestructibility of some materials will eventually pollute the environment because the global ecosystem is closed and limited and not infinite. Ecological transformations in the environment have a direct relationship with excessive use of natural resources, and the continued use and extraction of these resources should be controlled. At first, natural resources were thought to be unlimited and there was no fear of ending or lacking them, but with the increasing use of natural resources to meet technological needs, the idea of ??these resources being unlimited has become invalid. Since the interruption of the flow of progress may have serious or even catastrophic results, and on the other hand, the economic infrastructure and the flow of progress depend on natural resources, special attention is required in the matter of exploiting the available resources by modifying techniques and implementing extensive saving programs, and it became clear that in the field of using natural resources, we must adopt a method that maximizes the use of the minimum resources. Natural resources are generally divided into two categories: renewable such as forests, pastures, fish, non-renewable game animals such as coal, oil, natural gas and other minerals. Man can be sure of meeting his permanent needs from natural resources only if he keeps the population and the amount of permanent demands at a balanced level so that the circulation of materials in living organisms and soil is as fast as it is used. At the present time, when due to economic growth and population growth, the amount of consumption and human needs is increasing day by day, the protection of natural resources is important, for example, due to excessive grazing and the use of wrong agricultural methods, many green and fertile fields have turned into barren and useless deserts. The great river Rhine is so polluted that it is almost impossible to return to its original state. The source of fish in the rivers and seas is decreasing day by day and this huge source of protein production in the world is being destroyed. Fortunately, currently programs are being prepared to protect the fish species and prevent the pollutions that cause such a form in most countries of the world. Since the beginning of history, fishes have been considered as food for the human population. Fishing is said to be one of the oldest occupations of mankind and there is evidence that the ancient Chinese knew how to raise fish long before Christ. However, the scientific study of fish has no ancient history. In fact, there was no study before the 18th century AD, until this time various factors led to the beginning of ichthyology and the scientific study of fish. Since the beginning of the 20th century, ichthyological research has been developed in the following basic fields: 1. Classification and distribution. 2. Anatomy. 3. Physiology and biochemistry. 4. Pathology. 5. Population structure and dynamics. 6. Genetic evolution. 7. Conservation. This fact is known in a way that the knowledge of fish biology, especially in cognitive form, length and weight relationships, growth factor, reproduction, food and eating habits and so on. It is very important and it is not only important in raising our academic awareness, but its use in increasing the efficiency of technology for fisheries institutions in order to advance the wise management of fish farming is also very important. Fishes are very important in human life and are important natural sources of protein. They provide some other useful products, and they also play a role in the economic income of some nations. The gradual reduction of commercial fish stocks is caused by their over-exploitation and the changes in their habitat are one of the important reasons for the necessity of fish biology science (Adali, 2018).