feline leukemia virus

例句：

1. 1. The feline leukemia virus is responsible for the death of many cats.
   猫白血病病毒是导致许多猫死亡的原因。
2. 2. The virus has been found in various species of cats and dogs.
   这种病毒已在各种猫和狗中被发现。
3. 3.Researchers are working to develop a vaccine against this virus.
   研究人员正在努力开发一种针对这种病毒的疫苗。