Your question is totally wrong on itself!
“犭”（反犬旁/犬部） is a radical of Chinese Characters (Han-Zi,汉字) which is only for forming/making up some single Chinese Characters.
In the creating era aka ancient times, people used “犭”(a radical, the variant of 犬 i.e. dogs) to make some Characters which is with some relation to beast such as 猴(monkeys)、狮(lions)、狐狸(foxes)、猛(violent, adj.)...
The original design of Character “犹” which traditional form is “猶” is as follows:
犭 <---> 犬 ----> Dogs
酋 <---> 加时加料酿制的醇酒 ----> Doing a materials&time-consuming brew ---> 长时间精心培育 ---> Carefully nurtured for a long time
犭 + 酋 ---> 猶 ---> The dogs which were nurtured for a long time ----> Dogs/Something meet the target or template ----> 如同、相似 ---> be similar to
To sum up: 犹 = 猶 = be similar to
“犹” sounds yóu/Yew/Jew. So, in the word “犹太人”, the Character “犹” is totally Phonological-TRANSLITERATION for יהודים (Yehudim)!
Exactly NOTHING is with any relation to dogs/beasts/derogating/ethnic/political at the Character “犹” in the word “犹太”.
Please do not make an exceeding interpretation:)