Dexters produce 10-12ltrs (2.9 gallons) a day for 305 days a year. a jersey produces 22ltrs(5.8 gallons) per day, how much milk can you use? I assume you will share with the calf but still that's an awful lot of milk every single day.
Do you plan to make value added dairy products? Do you have any use for excess milk? Could you just get a second Dexter in a year or so to make up the anticipated deficit by then? Will you be clearing (or thinning and removing underbrush from) any of the heavily wooded areas?
All of those are questions that are, or might be relevant to giving you good advice.
How many in your family? How much milk do/ would you consume? Do you have time/ desire to make cheese, yogurt, kefir, ice cream, etc, on top of your daily milk drinking? The place to start is with your own consumption, and your willingness to find ways to use excess milk.
The only thing...more expensive than education is ignorance.~Ben Franklin
Jerseys have more butterfat in their milk than Dexters, so you can make more butter from them, but from what I have heard, Jerseys seem more high maintenance than Dexters, and need better quality feed.
Another consideration is bull choice - Dexters need smaller bulls than Jerseys, so you might want to see what bulls are around locally or whether you want to do AI.
As an owner of a dexter milk cow, there are pros and cons.
Pros: Our cow is very hardy, with no health issues, masitis or otherwise.
She is not picky about feed, produces very well on grass or hay, even if not the best quality. We don't have to feed any grain.
They don't eat as much as a jersey
Our cow has never had any issues calving, and she is 10 years old with plenty of life left in her
Milking is easy to do by hand and does not take long because there is not much milk.
We don't have any extra milk (this is both a pro and a con)
We don't get much milk. Right now it is just my wife, 7 month baby, and me. And we go through most of the milk we get just making yogurt, ice cream, and daily consumption.
We only get about 6-12 cups per milking depending on where she is in her lactation. Granted, we don't have a "milking" dexter.....those are much more expensive but she does have a decent udder and teats.
They don't have a long lactactation, it is hard to get dexters to produce for more than 9 months.
Calf sharing can be a pain because she is such a good mother, dexters are very vocal cows
Quality of milk (I will do a follow on post about this one)
Quality of milk:
We calf share for the first 5-7 months after freshening. You don't get milk for the first month because it all goes to the calf. Then we start separating the calf at night, which produces much bellowing for about a week. After that they still bellow, but only in the evening and morning, but no longer at one am (I always feel so bad for my neighbors).
While calf sharing, we pretty much get 1% milk. Maybe 2% on a good day.
Once we wean the calf using a no bellow nose weaner, our cream line is comparable to a jersey cow and is rich, yellow milk. We start milking twice a day and try to freeze the evening milk to use after we dry her off.
What does a metric clock look like? I bet it is nothing like this tiny ad:
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