MEANS OF PRESERVING WASTE MILK
Waste milk may be fed fresh as in Louisiana
(2) and Pennsylvania (1) trials. Practical experience indicates that if containers are kept
clean, waste milk can be held satisfactorily
under refrigeration for up to 3 days. Some
problems of lack of constant supply may be encountered, but in larger herds there usually
are at least a few lactating cows undergoing
treatment at all times. This would permit
feeding a portion of the calves on waste milk,
the remainder on fermented colostrum. The
advisability of mixing waste milk and colostrum
has not been investigated.
Waste milk may be fermented and stored for
subsequent use. Studies by Keys et al. (6, 7, 8)
showed that milk produced during milkings
three to six after antibiotic treatment fermented
as easily as did normal milk and sometimes
more rapidly than colostrum. That produced
during the first two milkings fermented slowly,
because of antibiotic content. Use of a starter
culture was recommended to speed fermentation. In all studies on feeding fermented waste
milk to calves, production from all six post
antibiotic treatment milkings has been pooled
and allowed to ferment (6, 10, 12).
Only limited information is available on use
of preservatives with waste milk. Otterby et al.
(10) acidified waste milk (or colostrum) with
propionic acid at .7% vol/wt and stored it in
plastic-lined garbage cans. One group of calves
in the Pennsylvania study (1) was fed waste
milk treated by addition of .05%, by weight, of
formaldehyde and stored in plastic containers.
In both studies, calves were reluctant to accept
the preserved milks.