What should be done if an animal is found in an unlocked enclosure, such as an open barn or cattle pen?
Lock the enclosure.
Lock the enclosure and inform the owner that you did.
Nothing.
If the animal is frightened in the enclosure, ensure that the owner gets it safely. Otherwise, nothing.
The question remains unresolved.
Why do we need a special Pasuk (Ish Imo v'Aviv Tira'u v'Es Shabsosai Tishmoru Ani Hashem) to tell us that a Kohen does not listen to his father to become Tamei or not to return an Avaida?
An Asei always pushes a Lo Sa’Asei aside.
Tumah is a Laav that can be suspended for Mes Mitzva, and Hashavas Avaida is suspended for Zaken V’Aino L’fi K’vodo, so they are somewhat weaker and would be pushed aside for Kibud Av.
Honoring parents is compared to honoring Hashem, so we would have supposed that it can even push aside an Asei and Lo Sa'Asei, together.
To compare Kibud Av to Shabbos; just as Shabbos is suspended (for Pikuach Nefesh), so to Kibud Av is suspended (for these Mitzvos).
To tell us that the father will eventually realize how special these Mitzvos are.
What does the fact that one must help with a Nochri’s animal tell us?
Clearly, that Tzar Baalei Chaim is D’Oraisa.
Possibly, to avoid Aiva.
That Preeka is said about Nochrim as well.
That Menchlechkeit says to assist a Nochri in need.
That we need not suspect a Nochri of carrying Yayin Nesech.
What does the fact that someone must help his Sonei load his animal, rather than his Ohev unload his animal, tell us?
That Tzar Baalei Chaim is not D’Oraisa.
That the Ohev discussed is a Nochri.
That the Yetzer Hara will get someone to do a smaller Mitzva so he won't do a bigger Mitzva.
That breaking one’s Yetzer Hara is more important than Tzar Baalei Chaim, even if it is D’Oraisa.
That Te’eena is in general a bigger Mitzva than P’reeka is.