Rav Yehuda said in the name of Rav, "If an animal falls into an irrigation ditch [on a festival], one may bring and place pillows and blankets under it, so that it can rise up [from the ditch] on its own . . . [Problem: In doing so] does he not nullify the [blankets and pillows] from their Shabbat use!?! [Solution: Rav Yehuda] claims that nullifying an object from its Shabbat use is a Rabbinic prohibition, while relieving an animal's pain is a Torah requirement. The Torah requirement comes and defers the Rabbinic prohibition.
As we move into the summer months, I wanted to revisit this source that we saw earlier in the year. As we mentioned the last time we saw it, this source limns the boundaries of our responsibility to protect our animals on Shabbat. According to this source, one may violate a Rabbinic commandment to preserve an animal from suffering on Shabbat. Here we see that the destruction of the blankets and pillows (usually forbidden on Shabbat) is legitimate if the purpose is to preserve the animal from harm.
I received an email from a close reader the last time we saw this source. She noted that I did not mention whether or not one may violate a Torah prohibition to save an animal on Shabbat. Clearly, our Sages felt that one may desecrate Shabbat in any way to save the human members of our communities. However, the implication of Rav Yehuda's reasoning is clear: in his view one may violate a Rabbinic prohibition to save an animal on Shabbat, but one may not violate a Torah prohibition to do so.
Do we find this troubling? Our Sages clearly held that the preservation of human life in our communities was a greater value than preserving the sanctity of an individual Shabbat. However, they (or at least Rav Yehuda) believed that Shabbat trumped the value of preserving animal life. This fact is perhaps a window into the importance that they ascribed to the sanctity of Shabbat.