Middlebury register. (Middlebury, Vt.) 1886-1937, 1893-09-01
STATE AGRICULTURAL
EXPERIMENT STATION.
BURLINGTON. Vt. 1913

Buletln no. 90 Newspaper bullclln NO. IL.
ANNUAL REPORT OF THE DIRECTOR
PART II.
Variations In Quantity and Quality of MILK.
A full record has been kept at the sta.
ton of the milk of each COW year aftel
year, and many thousand analyses made.
The voluminous records now ON file fur.
hish abundant data for determining the
changes that take place in the quantity
and quality of the milk of COW and
the influence that various circumstances
have on the quantity and quality.
A study of these records leads to the
following conclusions:
First-All COWS shrink in quantity of milk as
they get further from calving. If they are far
row, this shrinkage in quantity is accompa-
MED by almost no change in quality, even ui,-
til they go dry, provided they are still farrow.
If they are in calf, the milk increases in quail
ity as it decreases in quantity. This increase
is slight-but one-twentieth during the first
six months after calving-but becomes quite
pronounced just before the COW goes dry.
Second-CONs that calVe in the spring aver
age giving more milk during the first three
months after calving than those that calve in
the fall. For the seventh, eighth and ninth
months this % reversed. Fall cows show
smaller variations in the quality of the milk
than cows that calve in the spring
Third-The milk of a cow for the first few
days or weeks after calving is very variable in
quality. On the average it is thinnest just
after calving, becomes slightly richer duril g
the next two weeks and then holds almost
uniform in quality for the next four or five
months.
Fourth-Cows vary in the quality of their
milk from milking to the next and from
day to day, the quality rising and falling with
Il.
within per cent of fat. though one COW was
known to change 26S per cent in two dag ;.
The least change of any of the cows in the sta
ton herd during an entire period of lactation
is O33 per cent fat, the average change is / "a
per cent, and the greatest change 2.IS per cent.
The largest variation in yield of butter is from
milk that required 20 pounds to make pound
of butter to quality N milk which would re-
qure but III pounds 1t is probably possible
that cases may occur of doubling of the rich
ness of the milk during different times in the
same period of laciation.
Fifth-.Iust after Calving the milk is poore,
in fat and in solids not fat than just before t.e
COW went dry. The average drop in fat is ID
per cent, the greatest change being 23j POI
cent and the least 0.49 per cent. The average
change in solids not fat is fall of 0.47 ler
cent, with variations from decrease of 1.9i
TO an increase If Oh per cent
Sixth-Most cows give about the same quail
ty of milk year after year, beginning with this
quality at the first calving. There is no gon-
eral tendency for the milk to become either
richer or poorer as the COW grows older.
Seventh-From one calvng to the next COWS
may be expected to vary the general quality OF
their milk not much more than sixth of pei
cent fat, and scarcely ever will show varia-
/ ton of more than quarter of per cent.
+ Eighth-The milk of a heifcr tends to agree
very closely in quality to that of her dam. The
average variation is a third of per cent of fat
and the greatest difference is per cent-in the
case of an Ayrshire COW crossed with a jersey
bull.
Ninth-The present cheap, rapid and easy
methods of testing cows leave no excuse fol
any dairyman's not knowing the quality of IT,,
milk of each one of his cows. If two tests are
made, each of II mixed sample of four days
milk, one being taken six weeks after the COW
calves and the other six months after calving
the average of these two tests will agree allr os
exactly with the average quality of the mill
given during the entire milking period. Their,
will seldom be difference of as much as
quarter of per cent of fat.
Tenth-lf it is desired to know from test
nearer together what quality of milk COW
gives, very accurate results will be obtained b!
making two tests 10 days apart, four months
after the COW calves, each test being on
mixed sample of four days milk. The averag,
of these two tests with one-eighth of per cen
of fat added is surprisingly near the truth fo
the average quality of the years milk.
Eleventh-ln the long run, just about tn,
same results are obtained whether cows ar,
tested once month or twice n month.
Twelfth-COws that have been properly fec
at the barn do not shrink in quality of mill
when turned to pasture. They usually increas
10th in quality and quantity.
Thirteenth-Eull feeding with grain at thu
barn and while the COWS are on pasture pro
duces a much larger flow of milk during Apri
and May and causes the flow TO keep up con
sideraby later in the fall. No attempt wa
made to ascertain whether this increase wa
sufficient to pay for the extra grain
Fourtccnth-rhe milk produced by the COW
of Vermont during the entire year contains OF
the average Al per cent of fat, and would
rightly handled make pound of butter iron
each - pounds of milk.
Fifleenth-Ihe station herd was trouble
with abortion, and the trouble ceased afte
thorough disiIfecting with sulphur and plen
tiful use of laudanum. There is nothing I
prove conclusvely that the treatment was tn
cause of the cessation of the disease.
SiXteenth-The most noticeable effect Q
abortion on the quality of the milk is to max
it richer than it would have been had the co,
gone full time. This quality, however, fall
during the first few months after abort ior
until by the third or fourth month il is q
about the same quality as would have bee
given if the COW had calved naturally.
Seventeenth-The worst effect of abortion
the decreased quantity of milk given, whic
J with the cows of the station amounts TO abou
third of the full yield.
, Record of the Station Herd For 1892.
Careful and very complete records O
the station nerd We're kept during tn
year 1892 and showed that the II regula
members of the herd averaged 7,19
> pounds of milk. of such quality as t
3 make SOL pounds of butter each. TIL
records also showed that the herd con
tanned on the average 81 cows, and tina
these produced 7.02S pounds Of mil
apiece and 3S4 pounds of butter.
The best Ayrshire gave S,055 pound
of milk and $40 pounds of butter; tn
best three Holsteins, $50 pounds c
/. milk and 1888 pounds of butter; the bes
!, three Jerseys, 7,l30 pounds of milk an
l22 pounds of butter. The best recOr
r of any COW in the herd'within The yea
was Il, 224 pounds of milk and 506 pound
of butter.
Relative Value of IA Cow For Cheesemal
ing and Butter Making.
When the records Of the various COW