This post asks a similar question! https://forum.effectivealtruism.org/posts/pZT9FjRehCouvrRXz/seeking-ripple-effects

I personally think that we shouldn't weigh the ripple effects too highly in our decisions - if you care about reducing short term suffering and long term expanding the moral circle, I would be skeptical that a single intervention would better accomplish both of those objectives than two separate interventions tailored to each.

This reminded me of this older post: https://forum.effectivealtruism.org/posts/omoZDu8ScNbot6kXS/beware-surprising-and-suspicious-convergence

I feel like while ripple effects from health/animal welfare interventions are certainly something to consider, I wouldn't base too much of my decision on those because there are likely other more effective methods to achieve those impacts - for example, if the case for health is reducing suffering+ ripple effects in economic/technological growth, I would suspect that doing animal interventions (for suffering) and tech/growth interventions (for tech/growth) would do a better job at achieving both outcomes than making a single intervention which you hope will solve both.

Animal welfare seems likely more tractable, substantially more important, and vastly more neglected.