Improved aerobic and anaerobic swimming performance after exercise training and detraining in Schizothorax wangchiachii: Implications for fisheries releases.

Swimming performance (aerobic and anaerobic) is often used to predict the ability of fish to adapt and survive. Fish raised in captivity are typically poor swimmers and have lower survival rates than wild conspecifics when released into the natural environment. We investigated the potential for exercise training to enhance the swimming performance of Schizothorax wangchiachii held in captivity. Juvenile fish (mean body mass 1.40 ± 0.13 g, mean body length 4.36 ± 0.24 cm) were trained under five different regimes [3 cm·s-1 control group (C), 10 cm·s-1 for 6 (L6) and 12 h (L12) per day and 20 cm·s-1 for 6 (H6) and 12 h (H12) per day] for 30 days and then detrained for 20 days (i.e. no training). Aerobic (i.e. critical swimming speed, Ucrit), anaerobic swimming performance (i.e. endurance time at 1.2 or 1.5 Ucrit), and morphological parameters were measured at the beginning (T0), after 30 days of exercise training (T30) and after 20 days of detraining (DT20). Aerobic exercise training significantly improved the Ucrit, endurance time at 1.2 and 1.5 Ucrit of juvenile S. wangchiachii (P < .05). After 20 days of detraining, both the aerobic and anaerobic swimming performance of the H6 and H12 groups declined and no longer differed from the control group indicating a failure to maintain improved swimming performance, whereas improved swimming performance was maintained in L6 and L12 groups. No significant difference in swimming performance was found between 6 and 12 hours training at 10 cm·s-1. Thus, exercise at close to 10 cm·s-1 for 6 h per day for 30 days or a longer time periods prior to release appears to be a suitable regime for swimming performance enhancement, potentially increasing survivability of released S. wangchiachii in wild.

Comparative study on mineral elements in the roots of Rheum tanguticum from Qinghai-Plateau.

In the present paper, the authors analysed 10 mineral elements in the roots of Rheum tanguticum collected from 30 different habitats. The mean concentration values of the 10 elements decreased as follows: Ca>Mg>K>Fe>Mn>Cr>Zn>Ni>Cu>Se. Ca, Mg, K and Fe were abundant in this herb. Most elements varied over a wide range depending on the different habitats. The mineral element data were evaluated by principal component analysis to reveal the distribution pattern of elements in root. Four principal components (K-Ca factor, Cu factor, Mg factor and Zn-Se factor) of plant elements were selected. The authors' study provided a new scientific foundation for further studies and general application of this Chinese herb.

[Determination of trace arsenic and mercury in medicine animal horns by hydride atomic fluorescence spectrometry].

A hydride atomic fluorescence spectrometry has been developed for the determination of trace arsenic and mercury in medicinal animal horns. This method was simple, rapid and sensitive. The samples were digested with HNO3-HClO4(5:1), under the optimum conditions, the allowable amounts of 26 coexist elements were determined. The detection limits of this method were as follows: As 1.50 ng.mL-1, Hg 0.80 ng.mL-1. The relative standard deviations of 11 determinations were 1.2%-2.3% for As and 2.5%-4.7% for Hg. The recoveries were 98.9%-103.8% for As and 95.4%-105.0% for Hg.