We do not look at the moon phase when it pertains to weaning.  I do like to look at the phase pertaining to working the [small] calves; but if we are set up to have a working, I sure will not cancel it because the phase is not right.  The calves do seem to bleed less when the phase is in sync.

We tend to wean calves when they are about 9 months old.  Our weaning weights have steadily increased, and now we wean about a 600 lb. calf.  Keep in mind that we run a commercial cow/calf operation with black baldy cows.  The cows weigh about 1100 lbs.  Of course a bigger cow would/should wean a bigger calf...an elephant will wean a large calf, know what I mean?  It sure has worked good for us.

We give a shot or two at working (when they weigh about 100 lbs), including 7 way (Black Leg) ; and then we boost the 7 way and give a multi-symptom shot at weaning.  I can get particular about the shot schedule if you need me to.

We sell about 1/2 of the calves at weaning, and run the other half as stockers through the winter, and sell them the following spring.  Included in the 1/2 we keep through the winter is our replacement heifers.  The only thing we buy off of the ranch are bulls.  We cross the black baldy cow with either a Charlois or Angus bull.  We still keep a Hereford bull or two around, too, in order to get a true F-1 cross of the black baldy.

Regards

 **Edit**  I found my 2007 Almanac, and here is the info you were requesting:

Best days to _________ in Sept 07:

Wean: 9, 28

Breed:  15, 16

Castrate Animals :  22, 23

_____

set posts or pour concrete :  20, 21  (ha!)  (this really is listed in the Almanac...I can't see what difference it would make, but it is listed just the same...along with a bunch of other 'silly' things!)

Take it for what its worth!