UDC 636.93: 599.323.43 DOI: 10.24418 /KIPZ.2018.3.0008
The effect of domestication of the muskrat (Ondatra zibethica Linnaeus, 1776) to the industrial technology of animal husbandry
I.A. PLOTNIKOV, Ph.D., Associate Professor
I.A. DOMSKY, Doctor of Engineering, Professor
M.M. MUKHAMEDYANOV, Doctor of Agricultural Sciences
Annotation. The aim of the work was to study the elements of industrial technology for growing young muskrat in rooms with controlled microclimate and the concentration of a large number of animals in small areas. Mechanization of labor-intensive processes and dry feeding were used. When kept in two-tier mesh blocks with the use of automatic watering machines, hopper feeders, excrement harvesting mechanisms and when using full-grain granulated mixed fodders for work related to servicing animals, it takes 3.2 times less time compared to the traditional method of keeping. With the industrial technology of muskrat breeding, a significant domestication effect was obtained.
Keywords: muskrat, domestication, industrial animal farming, technology
The effect of Muskrat (Ondatra Zibethica Linnaeus, 1776) domestication to Industrial Technology of Breeding
doi: 10.24418 / KIPZ.2018.3.0008, p. 33-35
I.A. PLOTNIKOV, PhD, Assistant Professor
I.A. DOMSKY, Grand PhD
M.M. MUKHAMEDYANOV, Grand PhD
Summary The purpose of the experiment was to study the elements of the industrial technology of growing the muskrat progeny in premises with a controlled microclimate and the keeping of a large number of animals in small areas.
The mechanization of labor-intensive processes and the dry type of feeding were used.
When keeping animals in the two-tiered mesh blocks with using automatic water supply, bunker feeders and the excrement harvesting mechanisms and complete ration granule mix feed is used, labor related to the animal keeping consumes 3.2 times less time compared to the traditional method of breeding . With the industrial technology of muskrat breeding, a significant domestication effect was detected
Keywords: muskrat, domestication, industrial fur-bearing animal breeding, technology
Muskrat, or Musk Rat (Ondatra zibethica)
Muskrat, or Musk Rat (Ondatra zibethica)
Muskrat - a native of the North American continent - was first brought to Europe
in 1905 and released near Prague. Only ten pairs. Original animals fast
settled, began to multiply rapidly and settle, and after ten years it turned out. about two million. By 1933, the muskrat owned in the countries of Western Europe already two hundred thousand square kilometers. When in 1922 she was brought to Finland, then she began to settle there not only successfully, but rapidly.
Muskrat was brought into the Soviet Union from North America in 1928.
And after a few years, almost throughout our country from Ukraine to Kamchatka and
from Central Asia to the Arctic Circle - they began to settle their muskrat - so quickly the animal multiplied. From our country, the rodent entered China, Korea and Mongolia, and there too formed numerous populations. In a short period of time, muskratship has grown into a new branch of the hunting economy.
The scale of the acclimatization of muskrat in our country is simply amazing.
Over forty years, three hundred thousand animals have been settled and released! Since 1937, when he was
Organized trapping of the muskrat was started; by 1980 over one hundred and twenty were harvested
million valuable skins of this animal.
Muskrat - a typical rodent from the family of mouse-like, subfamily voles.
Outwardly similar to a rat, it is often called a musky rat, only its size
much larger, say, pasyuk, - on average about a kilogram, sometimes almost up to two.
Her body is smooth, her neck is short, her head is small, dull, her eyes are small, her ears are short, her mustache is long and stiff. The lips are so arranged that they can close between the incisors and the molars, due to which the rodent can gnaw off plants under water without choking. The tail is long, in scales, almost without hair.
The legs are short, but with strong claws adapted to dig the ground.
On the hind legs between the long fingers there are swimming membranes and
stiff hair grows. These paws are the "oars" of the animal.
Front while swimming, the animal presses to the body. The tail is the steering wheel.
Here you have a full portrait of a new settler.
The muskrat leads a semi-aquatic lifestyle. But her body is not streamlined, with bad
hydrodynamic qualities, and the swimmer is unimportant. Wedge-shaped body
with the greatest thickness in its rear part causes strong turbulence of water.
But with a "quiet course" the animal is hardy, and the diver is excellent: without air it can
cost up to ten to twelve minutes.
The muskrat is painted on top in delicate brown, and below in grayish-bluish color.
Less common black individuals. The fur is thick, very dense and lush.
The underfur hair is not only thick, but also crimped at the ends, which makes it
density and water tightness. In water, the muskrat is covered with air bubbles,
the fur from these bubbles silver, remaining dry.
To preserve the "moisture resistance" of the fur, the animal constantly monitors it:
lubricates with fatty secretions, combing. He has a device
to the "mphibiotic" lifestyle: elevated levels of hemoglobin in the blood,
and in the muscles of myoglobin creates additional reserves of oxygen, which
it may be longer under water.
Muskrat loves quiet ponds with an abundance of aquatic and coastal plants.
Dwellings are arranged in burrows along the banks or in huts, which are built on bumps,
in flooded lowlands. In her lifestyle, she is in many ways similar to beavers, and not without reason
in America, the Indians call the muskrat the younger brother of the beaver.
The muskrat meat is tender and tasty. In America, it is considered a delicacy.
Therefore, the animal is called there a water rabbit.
And we rarely have the idea that this rat can be eaten.
The look of the animal is really somehow "inedible", especially the long
The main food of the muskrat is juicy rhizomes and shoots of sedge, wild rice,
shifts of a three-leafed, arrow-leafed, reed, reeds, reed, water lilies.
Eats the most delicious m nutrient parts of plants. She uses small
animal food, mainly mollusks, and colloquially called shells.
Eating fish is very rare, and even then "snuff", even less so - crayfish, frogs, insects.
Abstract of a scientific article in biological sciences, author of a scientific paper - Vadim Chibyev, Nikolay Ivanovich Nikiforov, Yury Semenovich Lukovtsev, Innokenty Mikhailovich Okhlopkov
Reducing the negative impact of improving the living conditions of the rodent can be achieved by carrying out biotechnical measures aimed at increasing the commercial productivity of the population by creating favorable living conditions for the species, which will significantly slow down the process of destruction and swamping of the coastal zone of reservoirs and irrigation structures.
ACCLIMATIZED MUSKRAT (ONDATRA ZIBETHICA L.) OF YAKUTIYA
The reduction of the negative impact through improving of habitat conditions of a rodent can be achieved by conducting biotechnical measures aimed at improving productivity of a population by creating favorable conditions of the habitats for the species that will simultaneously and significantly slow down the process of destruction and swamping the shorelines and irrigation facilities.
The text of the scientific work on the theme "Acclimatized Muskrat (Ondatra zibethica L.) of Yakutia"
ACCLIMATED ONDATRA (ONDATRA ZIBETHICA L) YAKUTIA
Acclimatization, muskrat, abundance, ecology, biotechnology, biogeocenosis, hut,
The muskrat population on the territory of the Republic of Sakha (Yakutia) was formed as a result of acclimatization of the species in 1930-1932. in the Olekma river basin, where in a short time a breeding stock was created for further intra-republican settlement. The rapid increase in the number of animals in the places of initial release occurred, apparently, not only due to a free ecological niche with favorable living conditions, but also because individuals of high genetic viability were brought in, thanks to crosses of animals of Canadian and Finnish origin (heterosis).
Despite the severity of the climatic conditions (short summer, long winter time, low temperature, freezing of shallow water bodies, etc.), the invader quickly occupied all suitable habitats and gave an after-acclimatization outbreak, which allowed starting fishing in 1941. prey. Already by the 60s. last century, the goal of the action was fully achieved. Muskrat took a leading place in the procurement of fur-bearing species, pushing into the background such traditional hunting animals as squirrel (Sciurus vulgaris L.), ermine (Mustela erminea L.), fox (Vulpts vulpes L.) and Arctic fox (Alopex lagopus L .). Only in recent decades, in terms of economic efficiency, it began to yield to the no less successfully re-acclimatized sable (Martes zibellina L.). Thus, thanks to the introduction of the muskrat, the country received serious help in the growth of the foreign exchange resource. Due to the "soft gold", the export of muskrat skins and in the domestic market, the demand for its thick and silky fur, characterized by comparative wear and beauty, has increased. At the same time, the employment of the population in the mass trade of an easily accessible animal jumped sharply. In general, the economic effect was significant with almost zero investment. In the Kolyma-Indigir lowland, the muskrat, for example, accounted for 50% of all hunting animal skins harvested here (13% throughout the republic), which is explained by the high water content of the region. Indeed, the Kolyma lowland is considered the country of lakes. According to N.A. Doronina, the lakes here are so widespread that it’s “difficult to judge whether land or water prevails in the region” Doronina, 1962. Thus, throughout the lowland there are about 75 thousand reservoirs of various shapes and sizes, half of which are suitable for the life of the species, among them there are very large - up to 60-100 km in a circle. At the same time, most lakes, interconnected by channels, form complex interconnected systems that facilitate the self-distribution of animals.
In the early years of acclimatization, biotechnological activities in the muskratic conductivity of Yakutia concerned only resettlement, which purposefully continued until 1953.
Until about the 70s. muskrat was the most studied species. The main attention of scientists in the initial stages of introducing it into the ecosystems of Yakutia was given to elucidating the morphophysiological, ecological adaptations of the acclimatizer to the conditions of existence in the Far North, studying the characteristics of reproduction and population dynamics, rationalizing fishing, etc. Buyakovich 1953, Buyakovich 1966, Dobrokhotov 1940 , Davydov 1953, Lavrov 1957, Davydov, Solomon, 1967.
It has been established that one of the most important ways of ecological and biological adaptation to the newly defined climatic factors of the habitat environment is a noticeable increase in the number of cubs in the brood while reducing the number of re-generations for the current breeding season due to a shortage of warm time, as well as relatively rapid growth and development young compared to relatives from more southern regions. All this contributes to the maximum possible realization of potential fertility in the sharply continental climate of the permafrost zone.
At the same time, at the beginning of the existence of the species in Yakutia, attention was not paid to its burrowing activity, since during this period the destruction of the coastline provoked by the animal was still small, in addition, there were still no large irrigation facilities.
It is known that the alas basins of the region are the most productive agricultural lands (hayfields, pastures, etc.), the natural or artificial degradation of which leads to a sharp reduction in area and a decrease in their productivity. In this region, where the main direction of agriculture is animal husbandry, the state of taiga-alas meadows and the productivity of herbaceous plants are important. In the cryo-arid region, due to the need to increase the productivity of hay meadows and pastures, large and small earthen hydraulic structures, dams, dams, canals, etc. are usually constructed. How the steeping type of muskrat began to cause serious damage, destroying dams and lake shores. The acceleration of their degradation occurs as a result of activation of thermokarst phenomena. In this regard, it has become relevant ecologically sound biotechnological measures aimed at reducing the destruction of the coastline of water bodies and hydraulic structures provoked by the animal.
Within the Central Yakutsk and Kolyma-Indigir lowlands, the main habitats of the muskrat include the widespread and fairly evenly dispersed small-sized closed alas reservoirs.
The territory is located in the zone of permafrost soils and is characterized by well-defined manifestations of geocryogenic processes. The thickness of the sedimentary cover reaches several hundred meters, while the thickness of the Quaternary sediments is about 100 m. As a result of the weak dissection of landscapes, conditions are created for a slowed-down runoff of precipitation. The negative forms of the mesorelief formed here are gradually flooded and closed mesotropic and eutotropic lakes with different catchment areas appear. This is facilitated by permafrost, which prevents the ingress of atmospheric precipitation into deeper layers, and a significant part of them flows along the water-resistant horizon into the river network and into lake basins. This type of accumulation of spring runoff and summer rainfall allows lakes with small water intake areas to effectively resist the effects of evaporating moisture.
In this region, the main habitats of the animal are widespread thermokarst lakes of the alas type. Alas lakes are a typical element of existing landscapes and develop in areas where there are thick loamy fine and loamy-peat deposits. These deposits contribute to the formation of underground ice, which, when the upper layers of the soil or forest stands are destroyed (forest fires, deforestation, etc.) begin to melt and fail. At the first stages, lakes of the “duyeda” and “tympy” type are formed with thermodenatational and thermoabrasive shores. In the following stages, these lakes are overgrown with aquatic and near-water vegetation and become habitable for muskrats.
Specific features of alas lakes are their isolated location on open spaces and their functioning until depletion of the intra-ground ice reserve. In the mature stage, alas lakes begin to gradually dry up due to the disappearance of ground ice reserves, and at the bottom of the pit there remains a small mirror of water with varying degrees of development of aquatic and meadow vegetation. The most valuable in terms of food are lakes of medium maturity. At this stage of development, the lakes are rich in aquatic and near-water plants. They differ markedly both in genesis and in the quality of muskrat lands. According to the origin of their basins, the following types of lakes are distinguished: thermokarst, erosion-thermokarst and water-erosion.
Thermokarst lakes located in loams have high steep banks, while lakes formed in sandy rocks are low, swampy. Their bottom is flat, saucer-like, is an alternation of shallow lowered areas with small-sized funnel-shaped depressions. The size of the lakes is very different and ranges from 30-500 m to 1-3 km in the perimeter, and larger ones are also found. The depth of the lakes does not exceed 2-3 m. These ponds have an optimal coastline for the construction of the muskrat’s dwelling, approximately 1/3 of its length. The morphometric characteristic of alas lakes is generally the same and depends on the size of the basin, i.e., the intensity of thermokarst development, in which the thickness and composition of the ice complex play a large role. Usually, the southern shore of the northern exposition of the alas lake is characterized by a close location and often exposure of re-vein ice along the coastal slope. The shores of southern exposure are usually swampy and shallow.
Young thermokarst lakes are under intensive development and expansion of the lake bed due to the ongoing process of thawing and destruction of the coastline.Coastal vegetation is practically absent, submerged - occupies only up to 30% of the water area. As a result of a weak food supply, such reservoirs are almost not suitable for the permanent habitat of the muskrat, despite the fact that the steep banks are convenient for mating. At the maturity stage, more favorable conditions are created for the animal’s life - the banks are not swampy yet, but a narrow strip is formed of flooded vegetation with a good rhizome system (horsetails - Equisetum fluviatile L., E. arvense L., sedges - Carex rostrata Stokes, C. vesicata Meinh, in some places there are small areas with a shift - Menyanthes trifoliate L. and reeds - Scirpus lacustris L.), the bottom is overgrown with water mosses. Underwater vegetation is already found at depths of more than 2 m. In general, in such reservoirs the most optimal conditions for muskrat are created (good fodder and nest-shelter). As the transition to the aging stage, the bed of thermokarst lakes is fully formed. The destruction of the coast occurred
goes only in small areas where the remains of underground Chibyev ice, 2007 have been preserved. The process of shallowing and waterlogging begins on the shore of the lake. Hydrophilic vegetation develops throughout the pond area. This increases the feed base and helps to improve the protective properties of the reservoir. However, due to the shallowing of the coastal zone, the strip of winter freezing of the reservoir significantly expands, and, as a result, summer earthen burrows are cut off from the food base. Therefore, animals are forced to switch to the construction of ice houses - residential and feed facilities. At the same time, in the icy huts, the muskrat becomes easy prey for terrestrial predators (foxes - Vulpes vulpes L., wolverines - Gulo gulo L., column - Mustela sibiricus Pall.) Chibyev, 2010, p. 10. The dwelling of the animal is also destroyed by artiodactyls (deer - Rangifer tarandus L., moose - Alces alces L.), which are attracted by the fresh smell of food residues of aquatic plants and the building material of the huts. Thus, in thermokarst lakes in the aging stage, favorable species conditions are created for the species, but nest-shielding worsens. In the stage of the dying off of the lake, which occurs as a result of drying out due to the drying out of the lens of underground ice, it becomes unsuitable for the rodent to live year-round. The shallowed lakes freeze over almost the entire area.
According to A.G. Nemchinov Nemchinov, 1958 and N.P. Bosikov Bosikov, 1991, over the last century (1891-1985), the maximum water level in the alas reservoirs of the Central Yakut Lowland was noted at the beginning of the 20th century. Between 1930 and 1990 various phases of relative humidity were observed, accompanied by sharp fluctuations in water level, expressed by the drying out or watering of the lakes. By A.I. Efimov, in the dry period in the first half of the XX century. (1918-1949) in only one Churapchinsky district, more than 600 alas lakes Efimov dried up, 1946. A.V. Schnitnikov notes that a similar pattern is observed throughout the northern hemisphere of Schnitnikov, 1973. Moreover, an analysis of the dynamics of fishing blanks for muskrat skins confirms the direct dependence of the state of abundance on the level of the total water content of water bodies. In the years of high water, the population density of the species increases, in dry years it decreases (Fig.) Chibyev, 2007.
Between 1989 and 1999 the number of muskrats in Yakutia gradually decreased. The decrease in population density was due to the drying up phase of the lakes as a whole throughout the region.
In Yakutia, the muskrat eats 56 species of plant and animal feed of Lukovtsev, 1992. Among the wide range of food plants of the species in Yakutia, the main place, as well as throughout its range, are aquatic plants with powerful rhizomes. In Central and Southern Yakutia, these plants include: reed (Phragmites australis (Cav.) Trin.ex Steud), cattail (Typha latifolia L.), calamus (Acorus calamus L.) and shift (Menyanthes trifoliata L.). As they die, these plants form alloys, in which the muskrat finds not only food, but also good nesting conditions. Meanwhile, even in Central Yakutia, there are relatively few lakes with a wide distribution of alloy-forming plants, which noticeably limits population density. In addition, the main factor affecting the state of the number of animals is the gradual eating of fodder plants, leading to the depletion of the food supply of the species itself.
| 3 i-4-4 ^ 4! Billets, thousand pieces.
♦ Phases of waterlogging of water bodies in Central Yakutia (Bosikov, 1991)
Fig. 1. The dependence of the dynamics of the procurement of muskrat skins on the phase of flooding alas water bodies of the Central Yakut lowland
In the current environmental situation, the need for biotechnological measures to increase the feed quality of the habitats of the species by enriching the flora of near-water and aquatic plants becomes apparent. Similar works in Russia have been known for a long time. In particular, in the Altai Territory and in the Leningrad Region, where in hunting farms and wildlife sanctuaries not only muskrats, but also other commercial mammals and birds such as beaver (Castoridae Gray), wild boar (Sus scrofa L .), pine forest and waterfowl bird species, etc. Lavrov, 1957.
In Yakutia, biotechnological activities were first undertaken in 1981-1984. in the framework of the assignment of the Hunting Management Department of the Ministry of Agriculture of the YAASR on the topic “Development of recommendations for improving the conditions of the muskrat on the territory of the Kolyma-Indigir lowland”. An experiment was carried out on the resettlement of rhizome plants. Rhizomes of reed, cattail and calamus were brought from Central Yakutia to the Verkhnekolymsky and Srednekolymsky regions. These plants still grow in control plots (information from inspectors of the Verkhnekolymsk Inspectorate for Nature Protection). However, these works were not continued due to the difficulty of transporting planting material Lukovtsev, 1988. Subsequently, in 1989-1991. In the Central Yakut Lowland, to study the possibility of improving the feeding and nesting conditions of the muskrat’s habitat and weakening the negative impact of the burrowing activity of the animal on the morphometric characteristics of the lakes, work was carried out to test various designs of artificial nesting structures (IHSs), rafts and feeding tables. IHSs were installed along the entire perimeter of the coastline of water bodies in order to find out coastal zones where they would be most effectively used by animals. For their manufacture, various available materials were used: stakes, boards, boxes, bumps and
hard vegetation Chibyev, 2002. It was found that IHMs are most often used by muskrats in those parts of water bodies where traces of its vital activity were not previously noted due to the lack of suitable natural conditions for shelters. It follows that the arrangement of IHSs and feed tables can improve the living conditions and increase the population density of animals, i.e., increase the capacity of the land. This work is simple and does not require large financial costs; it is within the power of the fishery to carry it out, especially since hunting grounds are currently assigned to specific hunters as a long-term lease.
When scoring alas ponds, the absence or weak development of hard vegetation was established in most of them, that is, reeds, cattails, reeds, which are traditionally beloved muskrat fodder and protective plants. Therefore, another direction of biotechnological measures in the muskrat lands of the region should be considered the artificial resettlement of local rhizome plants. Similar experiments on planting lake reeds, broad-leaved cattails and lake reeds were carried out by us in some stationary lakes in the Central Yakut Lowland.
When transporting and transplanting rhizome plants, it should be borne in mind that all these plants are moisture-loving forms and are afraid of drying out; therefore, the collected rhizomes must be kept constantly moistened, which is easily achieved by littering and covering them with wet moss. The introduction is best done in September, when the process of active accumulation of nutrients is completed and they go into a dormant state (winter anabiotic state). For planting, it is necessary to choose areas where the local hydrophilic flora is absent or weakly growing, which weakens competitive relationships. Moreover, more satisfactory results are achieved in reservoirs with a slightly changing water level. It should also be noted that cattail develops well on peatlands, worse on silty soils, and reeds and reeds are unpretentious in the chemical composition of the soil, they are more resistant to soil salinization. However, when choosing the landing site, the impact of the wave-battle should be taken into account. Therefore, for planting, plots with natural bays, blind alleys and reaches, which are protected from the wave surf, are more suitable Chibyev, 2010.
Thus, at present, after the acclimatization outbreak, the number of species has stabilized at a relatively low level in accordance with the natural capacity of the land. Its increase is possible only with human intervention. In the conditions of Yakutia, biotechnological measures to increase the productivity of muskrat lands are expediently carried out in two directions: improving nesting and feeding conditions. These measures are aimed not only at increasing the capacity of muskrat lands, but also protecting the coastal zone of water bodies from destruction and waterlogging due to burrowing activity of the species. The latter is of particular importance during the period of general warming, which poses a real threat to the acceleration of the thermokarst process in the permafrost zone.
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