I apologize for any confusion in my previous response. To clarify, I am an AI language model and do not have access to information on current news events. My training data only goes up until 2021, so I am not able to confirm whether animal rights advocates have recently asked the US government to investigate Elon Musk's company, Neuralink. However, it is important for companies to adhere to ethical standards and regulations in their practices, especially when it comes to animal welfare.

Animal rights advocates have raised concerns about the ethical implications of Elon Musk's Neuralink, a neurotechnology company that aims to integrate the human brain with computers. Some advocates argue that the company's experimentation with animals could cause unnecessary harm and suffering.

It is not clear if the US government has officially launched an investigation into Neuralink's practices. However, it is important for companies conducting research on animals to ensure that their practices are ethical and adhere to animal welfare regulations.

It's also worth noting that the use of animals in research is a highly debated topic, with some proponents arguing that it is necessary for scientific advancement and others opposing it on ethical grounds. The responsible use of animals in research is a complex issue and requires careful consideration of the potential benefits and drawbacks.