A study on the use of freshwater rotifers (Brachionus angularis) as initial live feed for pangasius catfish (Pangasianodon hypophthalmus) larvae was undertaken to assess whether this initial feed improved P. hypophthalmus survival during the first 20 days of rearing. This study was comprised of three trials. The first trial contained three treatments and assessed the effectiveness of freshwater rotifers as initial feed compared to homemade feed and water flea (Moina macrocopa). In the second trial, P. hypophthalmus larvae were fed with (a) 100% freshwater rotifers, (b) 100% water fleas and (c) a combination of freshwater rotifers and water fleas (freshwater rotifers fed during first 3 days and then water fleas fed for remainder of experiment). In the third trial, the fish larvae were fed 3 densities of freshwater rotifers and then water fleas (3, 5 and 7 individuals per ml) to determine the most suitable feeding density for P. hypophthalmus larvae. Mouth opening was measured at days 0, 3, 6, 9, 12, 15, 18 and 20, whereas growth and survival were assessed at the end of each trial. These experiments demonstrated that P. hypophthalmus larvae: (a) exhibited a significant increase in survival rate when fed B. angularis rotifers or Moina micrura water fleas compared to homemade feed, (b) exhibited a significant increase in growth and survival rates when fed a combination of freshwater rotifers (first 3 days) and then water fleas (remainder) compared to feeding either freshwater rotifers or water fleas only, and (c) preferred a density of 5 to 7 individual freshwater rotifers and then water fleas per ml.

中文翻译：

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淡水轮虫Brachionus Angleis对提高pan属cat鱼（Pangasianodon hypophthalmus）早期生命历史阶段的成活率的重要性

进行了一项关于使用淡水轮虫（Brachionus angularis）作为pan鱼（Pangasianodon hypophthalmus）幼虫的初始活饲料的研究，以评估这种初始饲料是否在饲养的前20天中改善了P. hypophthalmus的存活。这项研究包括三个试验。第一次试验包含三种处理方法，并评估了与自制饲料和水蚤（Moina macrocopa）相比，淡水轮虫作为初始饲料的有效性。在第二项试验中，P。hypophthalmus给幼虫喂食（a）100％的淡水轮虫，（b）100％的水蚤和（c）淡水轮虫和水蚤的混合物（在前3天喂食淡水轮虫，然后在其余实验中喂水蚤）。在第三次试验中，给鱼幼虫喂食3倍密度的淡水轮虫，然后给水蚤（每毫升3、5和7个个体）确定最合适的下眼睑疟原虫喂食密度。在第0、3、6、9、12、15、18和20天测量张口，而在每次试验结束时评估其生长和存活率。这些实验表明，P。hypophthalmus幼虫：（a）饲喂B. angularis轮虫或Moina micrura时，存活率显着提高。 与自制饲料相比，水蚤（b）与仅饲喂淡水轮虫或水蚤相比，组合饲喂淡水轮虫（头3天）然后水蚤（剩余）时，生长和存活率显着提高，并且（c）优选密度为5至7个单独的淡水轮虫，然后每毫升水蚤。