I agree there are lots of un-ethical ways to manage dairy animals. The important thing, is that there are ethical ways. If something seems unethical to you, dont do it. You do not have to wean babies at a certain age, or feed supplements that increase milk production, or do anything that feels wrong. Keep modifying your management until you find the sweet spot where dairying is a harmonious and ethical pursuit. It exists.
Here is what I have reached with my dairy cows, that I feel is very much ethical and wonderful-
We milk once a day, only milking during fresh pasture season, no supplements except kelp and salt. Lots of people think that because their pastures arent good enough that feeding alfalfa or a little grain is a gesture of kindness. I disagree, sure hungry kids love candy, but it isnt good for their system. Farmers need dairy quality pastures before they get dairy animals. If the pastures arent good enough to support heavy lactation, start with
beef and use mob grazing to improve pasture quality. High energy/protein feeds force a ruminent into higher production which does strain their entire system.
Calves stay with their moms all the time for 3 weeks. We milk once a day, in the evening. After 3 weeks, calves get seperated during the day, and reunited with moms after milking in the evening. There is no stress. Calves hang out with calves during the day while moms enjoy the break from constant mothering. At 2-3 months of age, calves get weaned completely and put on our best clover pasture. They bawl, they want their moms, it's seperation anexiety. I consider it a part of growing up, stressful yes, unethical no. At this time the calves can still see their moms across the
fence, and get used to grown up life without milk in a couple of days. Growing up is a challenge, even for a calf.
Natural breeding to select wholesome genetics ensures that udder structure is physiologically compatibe with the animal's body type. Resist the commercial dairy model of unhealthily huge udders on skinny cows. You can and should select for cows with strong udder attachment, and compact but productive udders. Milk yield can still be excellent, udder health is better, and it certainly seems more comfortable for the animal. Pendulous udders are a bad thing and should be selected against in any dairy herd. When the variables of udder structure, milk production, feed, and calf nursing are in harmony, there is no undue hardship on the dairy animal. Finding and creating this balance is not easy, but it is absolutely doable.
There are a lot more ways to do something wrong than to do it right. Good on you for asking yourself if your system is ethical, that is commendable. Keep striving for a healthy, harmonious dairy system. When done right, there is nothing more satisfying in all of farming than a well run natural dairy. Love those cows!!!