Search PubMed⌕ Search

Biomedical subjects

L N Trut

Publications and source records attributed to L N Trut.

46 records · Page 3Linked to original sources
PubMedDate not supplied

[Behavioral and physiological characteristics of nonagouti mutation in gray rats during selection for aggressiveness].

The goal of this work was to find out to which degree the black coat color mutation nonagouti that appears in wild Norway rat in the course of breeding for the maintenance and enhancement of aggressiveness towards a human affects selected and other behavioral traits as well as stress reactivity and brain neurochemistry. Nonagouti rats displayed increased emotionality in the open-field and forced-swimming tests as compared to agouti animals, whereas there were no differences in anxiety estimated in the elevated plus-maze. Neither were there any differences in glucocorticoid reactions to a combined stressful procedure such as forced swimming. The dopamine content in the frontal cortex and striatum and noradrenaline content in the frontal cortex were increased in black rats as compared to gray rats. The result suggest that the nonagouti mutation in gray aggressive rats enhances the effects of selection for aggressiveness on some behavioral traits and brain catecholamine level.

Aggression↗
PubMedDate not supplied

[Maternal methyl-containing dietary supplementation alters the ability to learn in adult rats in swimming Morris test].

Maternal choline diet influences the spatial learning processes. In this work, the learning ability of adult progeny of mothers who had received methyl diet enriched with choline and betain during pregnancy and lactation was studied in Morris test. The introduction of the diet to pregnant rats resulted in an increase in the time of search for invisible platform and time of swimming near the pool walls in offsprings, which meant a worsening of their learning ability. It was also found that change in platform searching strategy was not associated with an increase in anxiety of male rats. Possible involvement of maternal methyl diet in the change of expression of genes which control development of the nervous system is discussed.

Animals↗
PubMedDate not supplied

Adrenal reactivity to ACTH age changes in silver foxes inheriting different defensive behaviors.

We have studied the influence of selection for behavior in female silver foxes upon their adrenal reactivity to ACTH. It has been found that in the first year of life, in females from a population selected for domesticated behavior (tame), there is no differentiated adrenal response to different doses of ACTH. In wild females during the first year of life, varying strength of adrenal response to large and small doses of ACTH is noted. During the second year of life, the differential adrenal response to different doses of ACTH is improved in females of both behavioral groups; the reactivity of tame second-year females to small doses of corticotrophin surpasses that of wild second-year animals. It is concluded that during ontogeny in domesticated silver fox females there is a retardation in the establishment of an adequate response to ACTH by the adrenals, as compared to nondomesticated females.

11-Hydroxycorticosteroids↗
PubMedDate not supplied

[Gonadal endocrine function in female silver foxes selected for domesticated behavior].

Selection for domesticated behavior in female silver fox is accompanied by a number of changes in endocrine function of ovaries. Significant changes in peripheral blood estradiol and progesterone levels and their production by gonads during anestrous may be an endocrine basis for out-of-season activation of reproductive system and earlier beginning of seasonal reproduction in domesticated females. The increase in the hormone level during preimplantation period of pregnancy and before parturition in tame foxes may influence their productivity.

Animals↗
PubMedDate not supplied

[Photoperiodic control of gonadal endocrine function in silver-gray foxes and its alteration during domestication].

Studies have been made on the level of estradiol and progesterone in domesticated and nondomesticated female silver foxes under different photoperiodic regime. The duration of the "light--darkness" cycle was equal to 24 h. Total duration of the light period was equal to 9 1/2 h; illumination was natural for 7 h, being artificial for the rest 2 1/2 h in a dark part of a day. It was demonstrated that additional illumination affects the hormonal level and sexual activity, the effect being dependent on the particular time of illumination. Nocturnal illumination significantly increased the level of sex hormones in the blood, domesticated animals being more sensitive as compared to nondomesticated ones.

Animals↗
PubMedDate not supplied

[Morphofunctional status of the adrenal cortex in female silver foxes and the effect of domestication and photoperiodic conditions].

Studies on 7-day-old and 8-month-old female silver foxes indicate that additional photostimulation affects to a various extent morphological and functional condition of the adrenal cortex in animals selected and unselected for the domestication type of behaviour. In relatively wild foxes, additional illumination stimulated the activity of the reticular zone, whereas in domesticated animals the same photoperiod increased the activity in the fascicular zone. It is suggested that selection of silver foxes for the domestication type of behaviour affects the sensitivity of the adrenals to external illumination.

Adrenal Cortex↗
PubMedDate not supplied

[Effect of lighting schedules on the ontogeny of gonad and adrenal endocrine function in female silver-black foxes Vulpes vulpes with two genetically determined types of behavior].

Additional illumination of animals nonselected for domesticative behaviour, results in the earlier increase of estradiol level in the blood and in higher production of this hormone by the gonads during pubertal period. Artificial illumination regimes do not significantly affect estradiol-producing activity of the ovaries in animals selected for domesticated behaviour. At the same time, additional illumination of the females with this type of behaviour increased progesteron-producing function of the adrenals during sexual maturation. Thus, selection of silver foxes for the domesticated type of behaviour affects the sensitivity of hormonal function of the ovaries and adrenals to photoperiodic factor of the environment.

Adrenal Glands↗
PubMedDate not supplied

[Features of the structure of the adrenal cortex in domesticated Vulpes fulvus silver foxes during postnatal ontogeny].

Studies have been made on the structure of the adrenal cortex in relatively wild and domesticated male and female silver foxes at the age of 1-7 days, 1, 2 and 8 months. It was demonstrated that during domestication, deep morphological changes in the adrenal cortex take place which indicate the decrease of functional activity in the fascicular zone and the increase of the activity in the reticular zone. Differences found in the first days of postnatal life become more evident in further ontogenesis.

Adrenal Cortex↗