Sex differences in the influence of mothers on the sociosexual preferences of their offspring

The extent to which "nurture" as opposed to "nature" determines behavior and sociosexual preferences in mammalian species is controversial although most recent interest has focused on genetic determinants. We report here that if sheep and goats are cross-fostered at birth, but raised in mixed-species groups, their play and grooming behavior resembles that of their foster rather than genetic species. There are no sex differences in effects on these behaviors, and other species-specific behavior patterns such as aggression, browsing, climbing, and vocalizations are unaffected. In adulthood, cross-fostered males strongly prefer to socialize and mate with females of their foster mother's species, even if raised with a conspecific of their own species. Castration within 2 days of birth slightly reduces the level of this altered social preference but mating preference following short-term testosterone treatment is the same as for gonadally intact animals. Cross-fostered females also show significant preference for socializing with females and mating with males of their foster mother's species, although this effect is weaker than that in both gonadally intact and castrated males. When cross-fostered animals are placed in flocks containing members of only their genetic species for 3 years, male social and mating preferences for females of their mother's species remain virtually unaffected. Females change to display an exclusive mating preference for members of their genetic species in 1-2 years although they still retain some social interest in female members of their foster species. Thus, there are clear sex differences in the impact of the emotional bond between a mother and her offspring in these mammals. Effects on males are strongest and irreversibly maintained even after altering their social environment, whereas those on females are weaker and mating preferences are clearly adaptable in the face of altered social priorities. These sex differences are presumably caused by pre-, or early postnatal, organizational effects of sex hormones on the brain.     

Evaluation of toxic assault on the immune system.

As a consequence of increased industrialization, human exposure to environmental toxins is growing daily. The effects of this exposure on the immune system is potentially a major health problem. Studies following human exposure have not unambiguously demonstrated a biologically significant weakening of the immune system, primarily because tests which show a high correlation with disease susceptibility have not been utilized. Such assessment of the immune system is particularly important in developing countries where regulation of environmental contamination may be less vigorous. At the same time, the ability to perform screening of large population in this setting is impaired. Measurement of the antibody response to an antigen used for routine immunizations provides a simple but very informative assessment and is particularly well suited as a minimalist approach to immune system assessment in developing countries.     

Maternal and paternal alcohol use: effects on the immune system of the offspring

There is no single mechanism which can account for such a complex biological phenomenon as immune regulation, nor is it clear how alcohol teratogenicity exerts its multiple adversive effects, including lasting immune deficits. Much of the research aimed at unravelling effects of pre- or early postnatal alcohol exposure on the organism's defense mechanisms and long-term health risks has been phenomenological. A better understanding of mechanisms which underlie alcohol effects on immune competency will require integrated studies of the neuro-immune-endocrine networks.     

Effect of toxic substances in anaerobic treatment of tannery wastewaters

Studies were carried out in the treatment of tannery wastewater using upflow anaerobic contact filter (reactor) and on the role of toxic substances viz tannin, sulphide, chromium (3+) in inhibiting the performance of the reactor. The influent COD concentration was varied in the range of 1500 to 16500?mg/l, at different hydraulic retention times viz 36,48,60 hr. The limiting concentrations of toxicity for the three substances viz tannin, sulphide, chromium (3+) were identified in terms of the performance of the reactor viz COD removal percent, biogas production etc. Toxic limits of the above mentioned substances were further estimated in batch process (in vials) to supplement the evidence. In anaerobic contact filter tannin beyond 914?mg/l inhibited the performance, whereas sulphide concentration even upto 180?mg/l and chromium (3+) concentration even upto 140?mg/l did not affect the reactor performance. In batch process tannin above 77 wt.% affected the anaerobic microbial growth. Hydrolysable tannin was present in these tannery wastewaters.     

Express control of toxic substances and pathogenic microorganisms. Immune analysis and immune sensors

In the review the overall characteristics of biological warfare components, which represent danger to people in the case of their application by military or terrorist groups are discussed. The main part of the review is devoted to modern approaches of antibody obtaining and, in particular, preparation of specific recombinant immunoglobulins as well as to different immune chemical methods of determination of individual toxins and pathogenic microorganisms. A special attention is paid to existing data about the development of rapid, selective, high sensitive, simple and fully automated instrumental methods on the basis of biosensor technology which is designed for the control of components of biological warfare in environmental objects. Additionally industrially manufactured biosensors and their characteristics are given and analyzed.     

The social interaction between mother and offspring during weaning in German Shepherd dogs: Individual differences between mothers and their effects on offspring

Seventeen litters of German Shepherd dogs were observed for 5–7 days per week between 3 and 8 weeks post-partum. Social behaviour patterns, aggressive signals towards the puppies and nursing were quantified. Mothers were found to differ in the frequency of both social and aggressive behaviour. Nursing declined during the period, while both agonistic and grooming behaviour towards puppies increased until the 7th week. During Week 7, agonistic behaviour patterns were found to be significantly correlated to grooming behaviour patterns. Some of these behaviour traits were significantly correlated to the puppies performance on a puppy test given at the age of 8 weeks. It is suggested that the interaction between mother and offspring may facilitate the appearance of submission, and the effects on later trainability are discussed.     

Impact of chronic ethanol intake of rat mothers on the seizure susceptibility of their immature male offspring

The aim of present study was to examine the impact of prenatal ethanol exposure on seizure susceptibility of the offspring. Pregnant Wistar rats were compelled to drink either 10% or 20% ethanol solution, as the only drinking fluid since conception up to the weaning of their offspring at the age of 28 days. Pregnant and nursing rats of the control group drank water. Electrophysiological experiments (repeated electrical stimulation and analysis of cortical afterdischarges duration) were than performed on their immature offspring. Rat pups were tested on postnatal day 18, 25, and 35. Shortening of afterdischarges duration was observed in 18-day-old animals (mothers drank 20% ethanol) when compared with age matched controls and failure of post-ictal depression phenomenon was found in 25- and 35-day-old animals. Our findings signalize that ethanol exposure during pregnancy influences seizure susceptibility by acting on excitatory/inhibitory brain systems and this effect is dose- and age-dependent.     

Malnutrition in utero and lactation: relation between the weight gained by the mothers and the development of their offspring

Physiological weight changes in rat dams and their offspring as sequelae of malnutrition during pregnancy and lactation have been studied. Daily monitoring of the body weight as well as the consumption of food (malnutrition dams 14 g during pregnancy and 20 g during lactation) and drink in control and malnutrition dams was conducted. The number of pregnant dams that completed their pregnant period successfully was registered as well as the number and weight of the pups at birth and their evolution over a period of a month. The percentage of mortality of the pups during that period has been studied. The present results indicate a highly significant decrease in body weight in experimental dams, which determines a retardation in the physiological development of the pups, and yields a higher percentage of mortality in the experimental animals than in controls. It can thus be concluded that malnutrition in utero and during lactation affects the ratio between weight gain for dams and the physical development of their pups.     

Neuromediator provision of the organs of immune system in benzpyrene intoxication]

The density of adrenergic innervation and relative content of catecholamines were investigated in rat lymphoid organs under different type of benzpyrene treatment. It was found that both ante- and postnatal influence of toxicant leads to a decrease of neurotransmitter providing of the thymus, spleen, mesenterial, iliac and popliteal lymph nodes. On the contrary, when mixed ante- and postnatal benzpyrene influence has place, the adrenergic innervation density and relative content of catecholamines are increased. We suppose that benzpyrene treatment of pregnant animals has specific "training" effect for monoaminergic systems of foetus and causes the increase of neurotransmitter providing of immunocompetent organs in conditions of repeat body and toxicant meeting.     

Maternal effects in Daphnia: what mothers are telling their offspring and do they listen?

Maternal effects can significantly impact offspring performance. Provisioning of offspring with energy stores can quantitatively alter their growth rates, survivorship, and future fecundity, and influence population regulatory mechanisms. In this paper, we show that maternal effects can also qualitatively affect offspring reproduction (i.e. their mode of reproduction). The freshwater herbivore Daphnia pulex can change the amount of energy allocated between asexual and ephippial egg production. Our experiments on individuals, experiencing “step‐up” or “step‐down” food manipulations, reveal that offspring qualitatively shift their energy allocation away from asexual reproduction to ephippial egg production when there is a simple mismatch between maternal and offspring food environments. We show that the response is asymmetric with respect to changes in food level, ephippial egg production is higher with a greater mismatch between environments, and that the effect can be observed in dynamic experimental populations. These results point to a “generational memory” that could challenge our interpretation of field patterns and mechanisms influencing population dynamics in Daphnia–algal systems.     

Mast cell changes in the organs of the immune system under physical loading

By means of histological and morphological methods reaction of mast cells has been studied in the thymus and inguinal lymph nodes of mature non-inbred white male rats, subjected to systematic physical loadings (daily swimming) with increasing time from 5 up to 100 min during 5 months. Morphological changes in the organs studied and manifestation of the mast cell reaction essentially depend on the degree of the animals' adaptation to the loading. In the animals adapted to swimming, decreasing area, occupied by the connective tissue elements, in comparison to that in the control--increasing cortical area, increasing number of lymphoid cells, decreasing number of the mast cells in the inguinal lymph nodes--are noted. When the adaptation of the animals to the loading is insufficient, outgrowth of the connective tissue elements, decreasing cortical zone, impoverishment of the parenchyma with lymphocytes occur. The number of the mast cells increases, many of them are at the state of degranulation.     

Effect of polychlorocamphene on the organs and their neural apparatus in pregnant animals]

Experiments conducted on pregnant albino rats showed that in daily oral administration of polychlorokamphene--a chlorine organic compound widely used in agriculature--in a dose of 12 mg/kg (1/20 LD50) there was interrelation between the structural and the enzymatic changes in the nerve elements of the organs under study. They consisted in the focality of the affection of the nervous structures of the brain cortex, and in increase in the destructive processes involving the nervous structures of the heart, uterus, spinal cord at the end of pregnancy. A peculiar enzymatic reconstruction with the preservation of the activity of the cholinesterase (CE)-positive pericellular structures (whose number was markedly decreased in comparison with control) was noted against the background of reduction of the CE activity. The prevalence of destructive processes by the end of pregnancy was conditioned by a considerable accumulation of the preparation in the heart, uterus, and the brain (as shown by thin-layer chromatography). The presence of polychlorkamphene in the organs of fetuses pointed to disturbances in the permeability of the transplacental barrier and to a possible influence of the preparation on the development of the fetal nervous system.