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L N Trut

Publications and source records attributed to L N Trut.

At least 19 recordsLinked to original sources
PubMed1997

[Effect of domestication of the silver fox on the main enzymes of serotonin metabolism and serotonin receptors].

In silver foxes significant alterations in the activities of basic enzymes of neurotransmitter serotonin metabolism as well as in the densities of receptors caused by selection for the absence of the aggressive defensive reaction to man were demonstrated. In the midbrain and hypothalamus of animals selected for the absence of aggressive behavior, the activity of tryptophan hydroxylase, the key enzyme of serotonin biosynthesis, was found to be remarkably higher than in animals selected for highly aggressive behavior. Domesticated animals were characterized by low activity of the main enzyme of serotonin catabolism, monoamine oxidase type A, increased Michaelis constant km, and an unchanged maximum reaction rate (Vmax). No changes in the specific binding of [3H]-ketanserin and [3H]-8-OH-DPAT in the frontal cortex of domesticated foxes were revealed; however, in the hypothalamus, the low values of Bmax for the [3H]-8-OH-DPAT specific binding were observed, indicating the decreased density of the 5-HT1A receptors. It is assumed that the transformation of a wild aggressive animal into a domesticated one taking place during directional selection is caused by hereditary alterations favored by artificial selection in the activity of the main enzymes of serotonin metabolism and serotonin receptors.

Aggression↗
PubMed1997

[D.K. Beliaev's evolutionary concept--ten years later].

D.K. Belyaev's evolutionary concept is considered in terms of (1) experimental results obtained during studies on domestication mainly in recent years and (2) modern views on evolution under extreme conditions and the role of the hierarchic system of regulation of genetic expression in evolution. Changes in neuroendocrine regulation in the course of long-term domestication are characterized, and the morphogenetic role of hormones and neurotransmitters is discussed. The effects of selection on the rate of some developmental processes and the importance of the resultant heterochronias for the morphogenetic consequences of selection for behavior are described.

Animals↗
PubMed1997

[The hooded allele and selection of wild Norway rats Rattus norvegicus for behavior].

Selection of wild gray rats for domestication (tame behavior) resulted in a sharp increase in the frequency of heterozygotes at the h allele of hooded, the main locus of rat depigmentation. The observed effect of the selection on the manifestation of the h allele is compared with similar effects giving rise to piebaldness in other animals subjected to experimental domestication. The results are discussed in terms of genetic specificity of piebaldness and of the selection vector.

Alleles↗
PubMed1993

[Is selection an alternative or complementary to variation].

This paper reviews the data demonstrating a large magnitude of variability during long-term selection. The attention has been focused on the studies revealing preservation of genetic variability under conditions of intensive selection force. The data are discussed in terms of both classical genetic mechanisms to preserve variability and possible influence of selection on frequency of de novo arising changes. It is supposed that the selection vector and the rate at which the changes occur are interrelated. If selection acts mainly on phenotypes controlled by polygenes with regulatory functions, then its effect on variability is the highest. It is underlined that behavioral and physiological traits represent the phenotypes of such type.

Animals↗
PubMed1993

[Comparative analysis of the level of heterozygosity for glucose phosphate isomerase (GPI) locus in silver foxes (Vulpes vulpes) of domesticated and control populations].

This communication is the first step of the studies on the correlation between protein polymorphism and the level of phenotypic diversity. The level of heterozygosity for glucose phosphate isomerase (GPI) locus was analysed in two populations of silver foxes. One of them has been selected for domestic behaviour during many years. This selection vector gave rise to many phenotypic novelties; 46% of the foxes analyzed has aberrant phenotypes. Another population was control bred under the same conditions of experimental farm of Siberian Dept. Russian Sci. with a commercial purpose. All the foxes analyzed from this population, except one, had a standard phenotype. Among 96 domestic foxes under analysis, only one heterozygotes for the GPI locus was detected. Among 112 control foxes, six were heterozygotes. In other words the data obtained indicate no correlation between the level of morphological diversity and the state of heterozygosity of the GPI locus.

Animals↗
PubMed1991

[Component analysis of craniologic characters of silver foxes (Vulpes fulvus Desm.) and their changes arising under domestication].

The data on cranial measurements performed in silver foxes indicate that there are differences in sizes measured between the farm foxes--bred population and the population selected for domestication. A method of principal components was used to analyse the cranial measurements and their changes under domestication. The first component covers about 50% of cranial diversity, which is interpreted as variation in the total skull size. This component clearly separates the two sexes, but not different populations. The second component presumably reflects the growth rate allometry between the skull length and width. The third and fourth components are measurements of skull width; the fifth one reflects the sizes of brain skull. None of these components clearly separate the foxes from farm--bred and domesticated populations. However, some differences in distribution are observed.

Animals↗
PubMed1991

[Intracranial allometry and craniologic changes during domestication of silver foxes].

Skull proportions and pattern of intracranial allometry in farm foxes of bred domesticated populations are compared. Changes in skull measurements and bivariate allometry are observed in domesticated males, which in this respect become closer to domesticated females. The changes in the allometry pattern in the domesticated population points to deep modifications of regulatory ontogenetic processes which underlie the allometric growth. However, morphological changes in domesticated foxes cannot be only accounted for by allometry.

Animals↗
PubMed1990

[The use of the method of principal components for phenogenetic analysis of the integral domestication trait].

In the course of long-term experiment on domestication of silver fox, it was necessary to determine the most important behavioral features, selection for which would give domestication effect. The mathematical method of principal components was used for the analysis of 20 fox behavior traits. The combination of the initial traits which reflected the structure of the integral trait, i.e. domesticated type of behavior, was determined. The practical use of this combination seems to more adequately estimate the level of domestication of a given animal, which is indispensable for subsequent effective selection.

Animals↗
PubMed1988

[Genetics and phenogenetics of hormonal characteristics of animals. VIII. Analysis of the variability of the corticosteroid function of the adrenal cortex of silver foxes during their domestication].

The contribution of genetic and environmental components in phenotype variety of corticosteroid adrenal function was studied in undomesticated and domesticated silver foxes during postnatal ontogenesis. The variation of basal and stress plasma corticosteroid level in animals aged 2, 4, 6, 8 months and in vitro secretion of the adrenal gland at the age 8 months was analysed. Significant genotype-depended variability was only demonstrated in undomesticated foxes under stress stimulation conditions. This phenomenon is manifested from the fourth month of life. However, significant genotype-depended variability was already revealed under basal conditions in domesticated foxes, on initial steps of postnatal ontogenesis. The peculiarities of genetic variability of adrenocortical function in foxes selected for domestication are discussed.

Adrenal Cortex↗
PubMed1985

[Relative hypertrophy of the right ventricle in silver foxes selected for domestication behavior].

Silver foxes selected for domestication behavior were found to have relative hypertrophy of the right heart ventricle, which was 21% as enlarged in males and 18% as enlarged in females as compared with non-domesticated animals. It was established by stereological methods that hypertrophy occurs mainly at the expense of an increase in the absolute and relative content of myofibrils in cardiomyocytes, with the absolute total volume of the mitochondria being equal both in domesticated and non-domesticated animals. It was shown by means of dissociated cell counts that in both animal groups, the absolute number of cardiomyocytes and their nuclei in the right ventricles is approximately similar. It is suggested that there is a relationship between right heart ventricle hypertrophy in domesticated foxes and variation in the balance of sympathetic and parasympathetic effects.

Animals↗
PubMed1980

[Genetics and phenogenetics of the hormonal characteristics of animals. VII. Correlation between brain serotonin and the hypothalamo-pituitary-adrenal system in domesticated and undomesticated silver foxes during emotional stress].

Two groups of silver foxes, selected according their behaviour with respect to man and non-selected ones, were exposed to restriction-induced stress. It was found that changes in the level of brain serotonin and its main metabolite, 5-hydroxyindolacetic acid, and elevation of plasma corticosteroids concentration in domesticated (tame) silver foxes were much less pronounced than in non-domesticated (non-tame) animals. Positive relationship between type of behaviour, brain serotonin metabolism and pituitary-adrenal axis response to stress was observed. It is suggested that such correlative pattern as changed pituitary-adrenal axis responses in domesticated animals may be due to changes in metabolism of controlling this axis brain transmitter serotonin.

Animals↗
PubMed1980

[Genetics and phenogenetics of the hormonal characteristics of animals. VI. Functional activity of certain chemoreceptors connected with the pituitary-adrenal system of silver foxes selected for their behavior].

Seasonal differences in the reaction of the pituitary-adrenal system in domesticated and non-domesticated silver foxes of both sexes to substances activating alpha-, beta-adrenoreceptors, and serotonin receptors were studied. It was shown that the reactivity of the pituitary-adrenal system in silver foxes of either type of behaviour is due, at least partially, to seasonal differences in the state of adrenergic and serotoninergic mechanisms. At the same time, in silver foxes selected for behaviour to man the reaction of the pituitary-adrenal system to the injection of substances activating adrenergic and serotoninergic receptors differs, during the year, from the reaction to these compounds in non-selected animals. The conclusion was made, that in the process of domestication changes take place in the state of serotonin- and noradrenaline mechanisms connected with the regulation of the hypothalamo-pituitary-adrenal complex.

Animals↗
PubMed1976

[Genetics and phenogenetics of the hormonal characteristics of animals. II. Changes in the reactivity of the pituitary-adrenal system and influence of the sex glands in selection of silver-black foxes by behavior].

Seasonal changes in the reactivity of adrenal cortex to ACTH and of the pituitary-adrenal system to psychic stress in intact and castrated domesticated (tame) and non-domesticated (non-tame) silver foxes of both sexes were studied. It is demonstrated that in tame foxes there are differences among the intact and castrated animal in their reaction to ACTH and psychic stress. These differences are maifested especially in autumn (September, October) which is the period of extra-seasonal sexual activity for domesticated animals. This points to the fact that the sex glands exert a great influence on the condition of central regulating mechanisms of the pituitary-adrenal complex and that the selection of silver foxes for tame behaviour changes the functional state of these mechanisms through the change of the functional state of the sex glands.

Adrenal Cortex↗