There are no laws that require you to be paid the same as a peer co-worker. The law says you can't be paid less BECAUSE you are female but it's not unlawful to pay you less in spite of being female. Plus, it's almost impossible to point to ONE individual who is paid more than you are and say it's discrimination.
Here's my take on what may be going on. You've been with this company for 19 years, doing the same job. The truth is if you stay with one employer for that length of time in the same position, it is very likely your pay rate is going to lag behind the "open market." That's just the way it is much of the time, regardless of anyone's gender. While this person doesn't have the applicable experience you have, he obviously had other experience that made him an attractive candidate and they had to pay what they had to pay to hire him. While your skills may be valuable to your current employer, they may not be all that marketable as poultry processing is a pretty narrow industry. The person they hired may have broader skills and thus is simply worth more.
If I thought this was gender discrimination, I'd be more than happy to tell you so. I can't say for certain what's going on where you work but I can tell you that nothing you shared in your post leads me to conclude that your gender is the issue here. More likely it's the fact that you stayed put all these years and quite possibly don't have skills that are all that marketable.
All you can do is to tell your employer you believe you are under-compensated and ask if they will consider doing something about it. Given that they just gave you a pretty generous raise, I don't know how agreeable they'll be, at least in the short-term.