I use baby oil on its own to detangle manes and tails - it also makes them really soft and shiny! I just put some onto my hands, rub then together and then work it through the horse's mane/tail. I then brush it through with a mane comb. Also as nattyhorseluver said baby oil works well on dark horses to give them a 'show sheen', however be very careful putting it on horses if they will be in the sun as it can cause their skin to burn so don't put it on any pink areas of skin etc.
(Also, while you're in the baby isle pick up some baby wipes - they work well for cleaning the face as they are very gentle and much more hygenic than using a sponge.

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