3种常用渔药对攀鲈幼鱼的急性毒性试验

为研究敌百虫、硫酸铜和二氧化氯等3种常用渔药对攀鲈(Anabas testudineus)的急性毒性,在水温(30±1)℃下,采用半静水式试验法进行了3种药物对攀鲈幼鱼[体质量(7.78±1.60)g、全长(7.89±0.44)cm)]的急性毒性试验.结果显示:敌百虫对攀鲈幼鱼的24、48、72、96 h半致死质量浓度...     

Tolerance and safety evaluation of sodium sulfate:A subchronic study in laying hens

Sodium sulfate (Na₂SO₄) is a readily available chlorine-free source of sodium, which could be used to reduce sodium chloride to maintain the ratio between chlorine and sodium in poultry diets. Dietary supplementation with excessive levels of Na₂SO₄ might be detrimental to bird''s health and performance. A subchronic study was carried out to investigate the potential adverse effects of an accidental oversupply of Na₂SO₄ in the diets of laying hens. Four hundred and fifty 21-week-old Hy-Line White layers were randomly assigned to 5 treatments with 6 replicates. The birds were fed diets supplemented with 0 (control), 0.3%, 0.6%, 1.5%, and 3.0% Na₂SO₄ for 8 weeks. Laying performance, egg quality parameters, clinical blood parameters, histopathology, intestinal barrier functions, and intestinal microflora composition were measured. No clinical signs of intoxication or mortality were observed during the experimental period. The results of this study showed that the optimal levels of Na₂SO₄ (0.3% to 0.6%) significantly improved the laying rates, average daily egg mass, and eggshell quality of hens compared to the control (P < 0.05). However, 3.0% Na₂SO₄ produced negative effects on laying performance, eggshell quality, blood biochemistry, and particularly on liver and kidney pathology, and intestinal morphology and barrier functions compared with the controls. Although minor changes were observed in clinical blood parameters of hens receiving 1.5% Na₂SO₄, these were not considered to be of toxicological significance due to the absence of any organ pathological changes in hens. In conclusion, our results indicated that a Na₂SO₄ concentration of 1.5% was non-deleterious to laying hens after a daily administration for 56 d, namely that dietary supplementation of up to 5 times the maximum recommended dose is safely tolerated by laying hens.     

硫酸软骨素的开发及生产工艺控制

介绍了硫酸软骨素的临床应用，如对听觉障碍、肝肾疾患、心血管疾病、眼病、肿瘤等具有治疗抑制作用，文中对其再开发及达标生产工艺，如方法选择１、温控操作、成品纯化等作了讨论。