My 5mo baby has a dip in appetite and also she does not want to be bottle fed, as a result, she is not taking in much milk. She will either play or resist the teat of the bottle. As a result, much of my breastmilk is wasted coz thrown away. She resists both breastmilk and formula milk. If we spoon feed her the milk, she is okay... Is it related to teething?

I think if it's teething, it would be more obvious, with baby crying and being fussy. My niece refused food for a while and she would throw a tantrum or fuss; we later found out that she started teething. Maybe baby is just distracted? It could also be a growth spurt. As long as baby is eating (even if it's by the spoon) and not losing weight or feeling sick, nothing to be too alarmed about, I reckon.