This is what I believe in and usually strive for. It has worked for me the last 3 years until last August of 08. We borrowed my Dad's Highland bull, Prince, who absolutely would NOT stay in our fences. We had only had him a week when we got an early morning phone call from a neighbor. Our bull was over there and had uprooted some decorative trees and shrubs they had.
Big oops. So we loaded him up and took him right back. Consequently, we only got 2 of our girls bred. Berretta and Teeny. Then the only choice I had was to wait for my young NZ sired Jersey bull to mature and take calves whenever they came, just to asure that the girls get bred. I actually really don't have any solid dates for calving, it will be a whole string of surprises probably born between August and next spring. Oh, well. I'll deal with that this winter and get back on track next year.
Why dairy seasonally? It follows the natural cycles of Nature for one thing. Cows give birth in the spring, just as the weather is warming but the flies haven't hit yet. In June, calves can be weaned and their mothers' are hitting peak production at the same time there is lush abundant pasture. Milking cows that are on grass full time is a joy. They are sparkling clean, and sleek and shiny. For us there is little to no barn cleanup, so ample time for milking and cheesemaking.
And the milk is nutritionally packed, golden yellow, and ripe with subtle variations and nuance depending on what field they are grazing, what stage the vegetation is at.
Come late October and early November, the grass is dying back and the cows are transitioning over to cut hay, as their lactation is waning a bit, the change in feed helps to lessen the flow of milk and prepare them for December dry off. I like to shoot for Christmas Eve for the final milking of the season. It is nice to be able to enjoy Christmas morning with the kids and not need to fit in the milking.
The composition of milk changes too, with the forage and also stage of lactation. Milk also varies from breed to breed and some cheeses are better made from specific milk based on the fat and protein content.
Here's what I can tell you about the milk of our Jersey cows:
Jersey cows have the highest fat level relative to protein and overall higher total solids.
For example Gale tested at 7.5% fat and 8.44 solids other than fat. Happy tested at 4.5% fat ( she was holding the cream for Brody, her calf) and 9.14 solids other than fat.
Milk from jersey cows is best suited perhaps for semi hard and soft cheeses due to the high fat content and the size of the fat globules. Jerseys have large fat globules which makes that cream rise so nice and thick, but can also make it hard to fully incorporate into hard cheeses. The quantity of milk being given usually but not always is related to fat content, as in in the beginning of lactation the cow produces, more but lower fat and toward the end of lactation fat increases as quantity decreases. Teeny at dry off time in March was giving 75% of each jar in cream! We were loving it!
Speaking of Teeny, she should calve today. Her ligaments are completely gone, and she was streaming milk from all 4 quarters this morning. Famous last words!