Causing economic losses in Brazil and Indonesia between 2002 and 2011 of over US$ 1 billion, infectious myonecrosis (IMN) constitutes a disease of mandatory notification to WHO (World Health Organization) and is responsible for constant damages in the production of the marine shrimp Penaeus vannamei. Although environmental factors such as high thermal amplitude, high concentration of nitrogen compounds and abrupt changes in salinity can alter the infection rate of this disease, there are still no studies. Thus, the present work aimed to evaluate the influence of temperature on the infectivity of IMNV in P. vannamei culture in a heterotrophic system. The experiment lasted 42 days, divided into two stages: (i) subjecting the shrimps to different temperatures (26 °C, 29 °C, 32 °C, and 35 °C) for 21 days; and (ii) viral challenge with IMNV via intramuscular injection (100 μL) also for 21 days, with evaluation of the shrimps by nested-PCR, histopathology and total and differential hemocyte count. The results obtained indicated that shrimps submitted to the highest temperatures evaluated (32 °C and 35 °C) had the highest post-viral challenge survival rates (85.42% and 93.75%, respectively), with less presence of lesions suggestive of IMN, although these shrimps were still positive by nested-PCR. No significant differences were observed in total hemocyte counts between pre- and post-challenge treatments (P > 0.05). In conclusion, the use of a temperature of 35 °C reduced mortality and viral load but altered the feed absorption, generating a reduction in zootechnical performance.

2002年至2011年间，传染性肌坏死（IMN）在巴西和印度尼西亚造成了超过10亿美元的经济损失，已成为世界卫生组织（WHO）强制通报的疾病，并对海虾生产造成持续损害。南美白对虾。尽管高热幅、高浓度氮化合物和盐度突变等环境因素可以改变该病的感染率，但目前尚无研究。因此，本工作旨在评估温度对异养系统中南美白对虾培养物中 IMNV 感染性的影响。实验持续42天，分为两个阶段：（i）将虾置于不同温度（26℃、29℃、32℃和35℃）下21天；(ii) 通过肌内注射 (100 μL) 用 IMNV 进行病毒攻击，持续 21 天，并通过巢式 PCR、组织病理学以及总血细胞计数和分类血细胞计数对虾进行评估。获得的结果表明，接受评估的最高温度（32°C 和 35°C）的虾具有最高的病毒攻击后存活率（分别为 85.42% 和 93.75%），并且提示 IMN 的病变较少存在，尽管巢式 PCR 检测这些虾仍呈阳性。攻击前和攻击后的总血细胞计数没有观察到显着差异（P  > 0.05）。总之，使用 35°C 的温度降低了死亡率和病毒载量，但改变了饲料吸收，导致动物技术性能下降。