Regarding the Islamic ruling of giving donations to some Muslim organizations for the purpose of Udhiyah, Dr. Muzammil H. Siddiqi, said:
The Sunnah of Udhiyah is that a person should do it by his own hands or be present when the sacrifice is done. The Prophet (peace and blessings be upon him) said to Fatimah (may Allah be pleased with her) to stand and watch when he was making sacrifice on her behalf. However, all jurists agree that it is permissible to appoint someone else to do the sacrifice and it is valid even if one does not witness it.
It is also recommended to eat some meat from the sacrificial animal as Allah says in the Qur’an, “… eat from it and give to the poor and needy..” (Al-Hajj 22: 36). It is also permissible to give all the meat to the poor people, if there are more needy people.
One can make one sacrifice on behalf of oneself and all his dependants and one can do more if one can afford it. It is also permissible to make sacrifice on behalf of the parents or other relatives and friends who have passed away as a sadaqah for them.