This question is similar to the question of salvation through faith or through works. Jesus said the mark of his followers is love (John 13:35) and that the two greatest imperatives are to love (God and neighbor, Matthew 22). And Paul said if you have faith but not love, you are nothing (1 Corinthians 13:2). So if you’re preaching Jesus but diminishing the importance of love in what you teach, then what you are teaching is worthless because love is the essence of what Jesus taught and because God is love (1 John 4:8). The faith/works question is settled in James 2:18 when he says, “Show me your faith apart from your works, and I will show you my faith by my works.” Similarly, we should teach the love of God by showing the love of God for his creation (including animals). If you say love is not important but only faith is important, then you have failed to understand the most important part of the gospel message.