The effect of scents on the territorial and aggressive behaviour of laboratory rats

The majority of works found in the literature mention odours as an important factor in the development of social lines and the unleashing of aggressive behaviour, but very few authors have studied more deeply the role that these odours play, how they influence behaviour and what importance the variations of these marks of identity may have. In the present work we analyse social relations presented by laboratory rats (Rattus norvegicus, Wistar breed) in seminatural conditions, with special reference to behaviours of dominance, territorialism and aggressiveness, and the importance that these marks of odour play on these behaviours. For this purpose, different individuals (from the established…

Nephrotoxic and hepatotoxic effects of chromium compounds in rats

The nephrotoxic, hepatotoxic and cardiotoxic actions of hexavalent chromium compounds, as well as their effects on lung, blood and circulation may contribute to the fatal outcome of chromium intoxication. Although trivalent chromium have been regarded as relatively biologically inert, there are a few salts of chromium III that have been found to be carcinogenic when inhaled, ingested or brought in contact with the tissues. Sensitive persons and industry workers have been subjects of dermatitis, respiratory tract injuries and digestive ulcers due to chromium compounds. In this work, the authors have studied the effect of trivalent and hexavalent chromium compounds on rats measuring the trans…

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Abstract Background Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18–49, 50–69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results NNVs were more favourable in su…

Facial attractiveness in men provides clues to semen quality

Abstract Facial attractiveness has been related to health in both men and women. Certain psychological, physiological, and secondary sex characteristics have been used as accurate markers of hormonal and developmental health. The main objective of this study was to investigate the capacity of women to select males of high reproductive quality based on their facial attractiveness. A total of 66 males were included in the study. Each of them provides a semen sample, and frontal and lateral photographs were taken. Semen analysis was made according to standard WHO (1999) guidelines for morphology, motility, and concentration. Moreover, a Sperm Index (SI) was calculated as the principal componen…

Oxygen uptake by excised gills ofProcambarus clarkii (Girard) from albufera lake of Valencia, Spain, under heavy metal treatments

The American red crayfish Procambarus clarkii, originally from Louisiana (USA) was introduced in Spain in the 70's in the Guadalquivir River swamps. It appeared first randomly and in a more regular basis afterwards since 1978 in the Albufera Lake south of Valencia and in the surrounding rice fields. Albufera lake and surrounding rice fields waters are being subject since the last three decades to very heavy load of sewage, toxic industrial residues including heavy metals and pesticides from the many urban and industrial settlements in the zone. In the present study, the authors have investigated the effect that heavy metals (Chromium, Cadmium and Mercury) have on the oxygen uptake by excise…

Temperature-toxicity relationships of fluvalinate (synthetic pyrethroid) on Procambarus clarkii (Girard) under laboratory conditions.

Acute toxicity of organochlorined pesticides to the European eel,Anguilla anguilla: The dependency on exposure time and temperature

Effects of temperature on the acute toxicity of heavy metals (Cr, Cd, and Hg) to the freshwater crayfish, Procambarus clarkii (Girard).

Chromium, an essential trace element for humans and animals is involved in normal carbohydrate metabolism; however, it is toxic at high concentrations. There is no evidence that cadmium and mercury are biologically essential but their toxicity for organisms is well known. Both cause toxic effects at low concentrations to most organisms, especially in combination with other environmental variables such as temperature. Lake Albufera and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic industrial residues (including heavy metals) from the many urban and waste waters in this area. In 1978, the American red crayfish Procambarus clarkii appeared in lake Albu…