Cardiorespiratory/sedative effects of a peptide identified in crotalic venom compared to acepromazine and xylazine in horses

ABSTRACT The purpose of this study was to investigate whether intravenous crotalphine produces significant sedation, as well as physiological changes, in healthy standing horses. Six mares, aged 8 years and weighing 415kg underwent three different treatments in a crossover design: TA (acepromazine: 50μg.kg-1), TC (crotalphine: 0.01μg.kg-1) and TX (xylazine: 1000μg.kg-1), intravenously. At various time points over 60 minutes, physiologic variables were recorded: heart rate, respiratory rate, and rectal temperature. The head height from the ground (HHG) was evaluated in centimeters. Data were analyzed using ANOVA followed by Dunnett’s test or Friedman followed by Dunn’s test, under 5% significance. Heart rate decreased significantly at M5 and M10 compared with Mb in TX (28±7, 26±6 and 40±8 beats/minute-1, respectively; p=0.0004). Respiratory rate and rectal temperature did not differ among groups or time points. The HHG significantly decreased in all groups compared with Mb at various time points (p<0.0001). In conclusion, crotalphine did not produce reliable and durable sedation in healthy standing mares and did not influence cardiorespiratory variables in a clinically relevant manner

Decision threshold associated with multiple measurements. Application to the synthesis of the environment monitoring results

When the sample activity is measured for various reasons several times, then with each measurement can be associated an individual decision threshold and limit of detection. Each measurement can be analyzed through its own decision threshold. The whole measurements can sometimes present contradictory results, some measurements being lower than the decision threshold and other higher. The problem then arises to build a decision threshold and a detection limit taking into account all the individual results, and to decide if the radioactivity is finally detected or not. It is interesting to note that it is possible sometimes that the decision threshold taking account all results makes it possible to decide that the radioactivity is present whereas the totality of the individual results are negative in terms of individual decision threshold. The purpose of this article is to show how these thresholds and these coherent limits cumulated can be determined in way according to the experimental conditions. In a general way a rigorous method of cumulating makes it possible to systematically decrease the decision threshold and limit of detection in terms of activity. This approach has interesting applications in gamma spectrometry with multi-emitters, discharge or periodical environmental measurements. On the basis of measurements realized by the IRSN within the framework of the national monitoring of the environment, we will see the potential impact of these methods on the final assessments