Dairy Sheep Symposium - the Department of Animal Sciences ...

perceived a problem with this setup so far, as long as we maintain a downhill slope from the teat
to the pipeline to avoid vacuum surges at the teat, and “slugging”, which can cause damage or
result in poor milkout. This manufacturer does offer a clawpiece, which would eliminate that
problem, should it begin to occur. This would most likely be seen early in the season when the
ewes are at peak production. We will be watching this closely with the changes we plan to make
for the 2002 season.
We have outgrown our initial 250-gallon bulk tank, and now use a 415-gallon. It is likely
that we will need to replace that with a 600-gallon tank for 2003. We must always be able to
hold three or four day’s worth of milk for fluid shipments.
The freezer was purchased used from a small grocer who was upgrading. It is 9 1/2 by 16 by
8 feet high. The box had 3 1/2 inch thick insulated panel walls. During installation, we added
two inches of extruded polystyrene to the walls and ceiling, and 6 inches of extruded poly under
and around the concrete slab to minimize required cooling loads. We hired a commercial refrigeration
company to supply and install the required condensing unit and additional evaporator to
meet the needs that we specified. We found out that the sizing of these components is primarily
a function of the pounds of milk you need to freeze daily, and secondarily a function of the
physical size of the freezer. In our case, the cooling capacity required to take 1200 pounds of
milk from 40 degrees to minus 10 degrees overnight is plenty to maintain the already frozen
product at minus 10 degrees. We use two 2 by 5 foot stainless steel wire shelving units obtained
from the freezer supplier to freeze the milk. Each unit has 5 shelves and can hold 15 bags of
milk. These are placed in the middle of the freezer in front of the evaporators, not against a wall,
which allows for maximum air circulation and optimum freezing conditions. Rapid freezing and
extreme cold storage temperatures are essential to maintain high milk quality. The freezer will
hold a maximum of 18,000 pounds of milk stacked in bags. To conserve freezer space pallets are
not stored in the freezer. We have learned through experience that, even though the floor has
insulation under it, bags placed on the floor to freeze will do so in a considerably longer time,
and will freeze primarily from the top. This leaves the milk in the center and bottom of the bag
at an above-frozen temperature for too long. We would expect that a similar thing would happen
if milk were frozen on a solid wood shelf.
Outside the freezer is a concrete slab where we assemble pallets of frozen milk for shipping.
A few of us working together can put together a pallet of milk in 15 minutes. There is no danger
of significant thawing of milk in the first two hours after it is removed from the freezer.
Below this slab is an approach for tractor-trailer trucks to back in for pallet loading. The height
differential of 50 inches allows for efficient loading with a simple dock plate and pallet jack.
The flow of ewes through the parlor is a straight line – in the south doors and out the north. We
have built an overhang on the barn where the sheep wait for entry to the parlor. This is about 12
by 90 feet, and allows 250 ewes to be sheltered before milking. We have found that this made a
significant difference in the amount of clean up required in the parlor after milking, and in our
ability to be milking sheep that are not dripping wet if it is raining. The ewes are usually very
calm in the parlor with very little to no urine or manure left behind. The area where the sheep
collect after milking is kept in sand to reduce probability of bacterial contamination for the ewes.
We currently plan to add facilities and equipment for lamb rearing in time for the 2002 lambing
season. This will include an insulated lamb rearing barn with the necessary pens, year-round
watering, and automated milk replacer mixing and feeding. We will then remove most lambs