Long P L, Johnson J, McKenzie M E
Department of Poultry Science, University of Georgia, Athens 30602.
Poult Sci. 1988 Feb;67(2):248-52. doi: 10.3382/ps.0670248.
The efficacy of mixtures of narasin and nicarbazin were evaluated by comparing broiler performance, susceptibility to heat stress, and the mode of action against Eimeria. In a floor pen trial, narasin (70 ppm) alone or in combination with nicarbazin at levels between 10/10 and 50/50 ppm gave significantly better performance than unmedicated birds or birds given nicarbazin at 125 ppm alone. Amelioration of nicarbazin-associated mortality with heat as a stressor was observed in birds given the 50/50 ppm mixture of narasin and nicarbazin: mortality in these birds was similar to that of unmedicated birds and was reduced by 15 to 20% of that occurring in birds in the nicarbazin (125 ppm) treatment. The narasin/nicarbazin mixture (50/50) appears primarily to prevent further development of sporozoites. However, in birds treated with 25/25 ppm of narasin and nicarbazin, both the deleterious action of nicarbazin on merogeny and the antisporozoite activity of narasin were observed.
通过比较肉鸡的生长性能、对热应激的易感性以及对抗球虫的作用方式，评估了那拉菌素和尼卡巴嗪混合物的功效。在地面平养试验中，单独使用那拉菌素（70 ppm）或与尼卡巴嗪按10/10至50/50 ppm的比例混合使用，其生长性能显著优于未用药的鸡或仅给予125 ppm尼卡巴嗪的鸡。在以热作为应激源的情况下，观察到给予那拉菌素和尼卡巴嗪50/50 ppm混合物的鸡，与尼卡巴嗪相关的死亡率有所改善：这些鸡的死亡率与未用药的鸡相似，比尼卡巴嗪（125 ppm）处理组的鸡降低了15%至20%。那拉菌素/尼卡巴嗪混合物（50/50）似乎主要是阻止子孢子的进一步发育。然而，在用25/25 ppm那拉菌素和尼卡巴嗪处理的鸡中，既观察到了尼卡巴嗪对裂殖生殖的有害作用，也观察到了那拉菌素的抗子孢子活性。
