|
DEC 4 1953
Bulletin 529
October 1953
UNIVERSITY OF FLORIDA
AGRICULTURAL EXPERIMENT STATIONS
WILLARD M. FIFIELD, Director
GAINESVILLE, FLORIDA
DAIRY CALVES
Their Development and Survival
P. T. Dix ARNOLD and R. B. BECKER
Fig. 1.-Jersey calves on a pasture of white clover and Dallis grass at
the Dairy Research Unit.
^S-H^ .
V
BOARD OF CONTROL
Hollis Rinehart, Chairman, Miami
J. Lee Ballard, St. Petersburg
Fred H. Kent, Jacksonville
Wm. H. Dial, Orlando
Mrs. Alfred I. duPont, Jacksonville
George W. English, Jr., Ft. Lauderdale
W. Glenn Miller, Monticello
W. F. Powers, Secretary, Tallahassee
EXECUTIVE STAFF
J. Hillis Miller, Ph.D., President
J. Wayne Reitz, Ph.D., Provost for Agr.'
Willard M. Fifield, M.S., Director
J. R. Beckenbach, Ph.D., Asso. Director
L. 0. Gratz, Ph.D., Assistant Director
Rogers L. Bartley, B.S., Admin. Mgr.3
Geo. R. Freeman, B.S., Farm Superintendent
MAIN STATION, GAINESVILLE
AGRICULTURAL ECONOMICS
H. G. Hamilton, Ph.D., Agr. Economist 1
R. E. L. Greene, Ph.D., Agr. Economist 3
M. A. Brooker, Ph.D., Agr. Economist
Zach Savage, M.S.A., Associate
A. H. Spurlock, M.S.A., Agr. Economist
D. E. Alleger, M.S., Associate
D. L. Brooke, M.S.A., Associate
M. R. Godwin, Ph.D., Associate 3
W. K. McPherson, M.S., Economist 3
Eric Thor, M.S., Asso. Agr. Economists
Cecil N. Smith, M.A., Asso. Agr. Economist
Levi A. Powell, Sr., M.S.A., Assistant
Orlando, Florida (Cooperative USDA)
G. Norman Rose, B.S., Asso. Agri. Economist
J. C. Townsend, Jr., B.S.A., Agricultural
Statistician 2
J. B. Owens, B.S.A., Agr. Statistician 2
AGRICULTURAL ENGINEERING
Frazier Rogers, M.S.A., Agr. Engineer13
J. M. Myers, M.S.A., Asso. Agr. Engineer
J. S. Norton, M.S., Asst. Agr. Engineer
AGRONOMY
Fred H. Hull, Ph.D., Agronomist 1
G. B. Killinger, Ph.D., Agronomist
H. C. Harris, Ph.D., Agronomist
R. W. Bledsoe, Ph.D., Agronomist
W. A. Carver, Ph.D., Agronomist
Fred A. Clark, M.S., Associate 2
E. S. Horner, Ph.D., Assistant
A. T. Wallace, Ph.D., Assistant3
IU. E. McCloud, Ph.D., Assistant 3
G. C. Nutter, Ph.D., Asst. Agronomist
ANIMAL HUSBANDRY AND NUTRITION
T. J. Cunha, Ph.D., Animal Husbandman s
G. K. Davis, Ph.D., Animal Nutritionist3
R. L. Shirley, Ph.D., Biochemist
A. M. Pearson, Ph.D., Asso. An. Husb.3
John P. Feaster, Ph.D., Asst. An. Nutri.
H. D. Wallace, Ph.D., Asst. An. Husb.3
M. Koger, Ph.D., An. Husbandman 3
J. F. Hentges, Jr., Ph.D., Asst. An. Husb. 3
L. R. Arrington, Ph.D., Asst. An. Husb.
DAIRY SCIENCE
E. L. Fouts, Ph.D., Dairy Technologist 1
R. B. Becker, Ph.D., Dairy Husbandman
S. P. Marshall, Ph.D., Asso. Dairy Husb.3
W. A. Krienke, M.S., Asso. Dairy Tech.3
P. T. Dix Arnold, M.S.A., Asso. Dairy Husb. 3
Leon Mull, Ph.D., Asso. Dairy Tech.3
H. H. Wilkowske, Ph.D., Asst. Dairy Tech.3
James M. Wing, Ph.D., Asst. Dairy Hush.
EDITORIAL
J. Francis Cooper, M.S.A., Editor3
Clyde Beale, A.B.J., Associate Editor3
J. N. Joiner, B.S.A., Assistant Editor 3
William G. Mitchell, A.B.J., Assistant Editor
Samuel L. Burgess, A.B.J., Assistant Editor:
ENTOMOLOGY
A. N. Tissot, Ph.D., Entomologist
L. C. Kuitert, Ph.D., Associate
H. E. Bratley, M.S.A., Assistant
F. A. Robinson, M.S., Asst. Apiculturist
R. E. Waites, Ph.D., Asst. Entomologist
HOME ECONOMICS
Ouida D. Abbott, Ph.D., Home Econ.,
R. B. French, Ph.D., Biochemist
HORTICULTURE
G. H. Blackmon, M.S.A., Horticulturist
F. S. Jamison, Ph.D., Horticulturist3
Albert P. Lorz, Ph.D., Horticulturist
R. K. Showalter, M.S., Asso. Hort.
R. A. Dennison, Ph.., P. Asso. Hort.
R. H. Sharpe, M.S., Asso. Horticulturist
V. F. Nettles, Ph.D., Asso. Horticulturist
F. S. Lagasse, Ph.D., Horticulturist2
R. D. Dickey, M.S.A., Asso. Hort.
L. H. Halsey, M.S.A., Asst. Hort.
C. B. Hall, Ph.D., Asst. Horticulturist
Austin Griffiths, Jr., B.S., Asst. Hort.
S. E. McFadden, Jr., Ph.D., Asst. Hort.
C. H. VanMiddelem, Ph.D., Asst. Biochemist
Buford D. Thompson, M.S.A., Asst. Hort.
M. W. Hoover, M.S.A., Asst. Hort.
LIBRARY
Ida Keeling Cresap, Librarian
PLANT PATHOLOGY
W. B. Tisdale, Ph.D., Plant Pathologist
Phares Decker, Ph.D., Plant Pathologist
Erdman West, M.S., Botanist & Mycologist'
Robert W. Earhart, Ph.D., Plant Path.2
Howard N. Miller, Ph.D., Asso. Plant Path.
Lillian E. Arnold, M.S., Asso. Botanist
C. W. Anderson, Ph.D., Asst. Plant Path.
POULTRY HUSBANDRY
N. R. Mehrhof, M.Agr., Poultry Husb. 3
J. C. Driggers, Ph.D., Asso. Poultry Hush.3
SOILS
F. B. Smith, Ph.D., Microbiologist'
Gaylord M. Volk, Ph.D., Soils Chemist
J. R. Neller, Ph.D., Soils Chemist
Nathan Gammon, Jr., Ph.D., Soils Chemist
Ralph G. Leighty, B.S., Asst. Soil Surveyor 2
G. D. Thornton, Ph.D., Microbiologist
C. F. Eno, Ph.D., Asst. Soils Microbiologist
H. W. Winsor, B.S.A., Assistant Chemist
R. E. Caldwell, M.S.A., Asst. Chemist 54
V. W. Carlisle, B.S., Asst. Soil Surveyor
J. H. Walker, M.S.A., Asst. Soil Surveyor
William K. Robertson, Ph.D., Asst. Chemist
O. E. Cruz, B.S.A., Asst. Soil Surveyor
W. G. Blue, Ph.D., Asst. Biochemist
J. G. A. Fiskel, Ph.D., Asst. Biochemist s
L. C. Hammond, Ph.D., Asst. Soil Physicist 3
H. L. Breland, Ph.D., Asst. Soils Chem.
VETERINARY SCIENCE
D. A. Sanders, D.V.M., Veterinarian '
M. W. Emmel, D.V.M., Veterinarian 3
C. F. Simpson, D.V.M., Asso. Veterinarian
L. E. Swanson, D.V.M., Parasitologist
W. R. Dennis, D.V.M., Asst. Parasitologist
E. W. Swarthout, D.V.M., Asso. Poultry
Pathologist (Dade City)
BRANCH STATIONS
NORTH FLORIDA STATION, QUINCY
W. C. Rhoades, Jr., M.S., Entomologist in
Charge
R. R. Kincaid, Ph.D., Plant Pathologist
L. G. Thompson, Jr., Ph.D., Soils Chemist
W. H. Chapman, M.S., Agronomist
Frank S. Baker, Jr., B.S., Asst. An. Husb.
Frank E. Guthrie, Ph.D., Asst. Entomologist
Mobile Unit, Monticello
R. W. Wallace, B.S., Associate Agronomist
Mobile Unit, Marianna
R. W. Lipscomb, M.S., Associate Agronomist
Mobile Unit, Pensacola
R. L. Smith, M.S., Associate Agronomist
Mobile Unit, Chipley
J. B. White, B.S.A., Associate Agronomist
CITRUS STATION, LAKE ALFRED
A. F. Camp, Ph.D., Vice-Director in Charge
W. L. Thompson, B.S., Entomologist
R. F. Suit, Ph.D., Plant Pathologist
E. P. Ducharme, Ph.D., Asso. Plant Path.
C. R. Stearns, Jr., B.S.A., Asso. Chemist
J. W. Sites, Ph.D., Horticulturist
H. O. Sterling, B.S., Asst. Horticulturist
H. J. Reitz, Ph.D., Horticulturist
Francine Fisher, M.S., Asst. Plant Path.
I. W. Wander, Ph.D., Soils Chemist
J. W. Kesterson, M.S., Asso. Chemist
R. Hendrickson, B.S., Asst. Chemist
Ivan Stewart, Ph.D., Asst. Biochemist
D'. S. Prosser, Jr., B.S., Asst. Engineer
R. W. Olsen, B.S., Biochemist
F. W .Wenzel, Jr., Ph.D., Chemist
Alvin H. Rouse, M.S., Asso. Chemist
H. W. Ford, Ph.D., Asst. Horticulturist
L. C. Knorr, Ph.D., Asso. Histologist
R. M. Pratt, Ph.D., Asso. Ent.-Pathologist
W. A. Simanton, Ph.D., Entomologist
E. J. Deszyck, Ph.D., Asso. Horticulturist
C. D. Leonard, Ph.D., Asso. Horticulturist
W. T. Long, M.S., Asst. Horticulturist
M. H. Muma, Ph.D., Asso. Entomologist
F. J. Reynolds, Ph.D., Asso. Hort.
W. F. Spencer, Ph.D., Asst. Chem.
R. B. Johnson, Ph.D., Asst. Entomologist
W. F. Newhall, Ph.D., Asst. Entomologist
W. F. Grierson-Jackson, Ph.D., Asst. Chem.
Roger Patrick, Ph.D., Bacteriologist
Marion F. Oberbacher, Ph.D., Asst. Plant
Physiologist
Evert J. Elvin, B.S., Asst. Horticulturist
R. C. J. Koo, Ph.D., Asst. Biochemist
J. R. Kuykendall, Ph.D., Asst. Horticulturist
EVERGLADES STATION, BELLE GLADE
W. T. Forsee, Jr., Ph.D., Chemist in Charge
R. V. Allison, Ph.D., Fiber Technologist
Thomas Bregger, Ph.D., Physiologist
J. W. Randolph, M.S., Agricultural Engr.
R. W. Kidder, M.S., Asso. Animal Husb.
C. C. Seale, Associate Agronomist
N. C. Hayslip, B.S.A. Asso. Entomologist
E. A. Wolf, M.S., Asst. Horticulturist
W. H. Thames, M.S., Asst. Entomologist
W. G. Genung, M.S., Asst. Entomologist
Frank V. Stevenson, M.S., Asso. Plant Path.
Robert J. Allen, Ph.D., Asst. Agronomist
V. E. Green, Ph.D., Asst. Agronomist
J. F. Darby, Ph.D., Asst. Plant Path.
V. L. Guzman, Ph.D., Asst. Short.
J. C. Stephens, B.S., Drainage Engineer
A. E. Kretschmer, Jr., Ph.D., Asst. Soils
Chem.
Charles T. Ozaki, Ph.D., Asst. Chemist
Thomas L. Meade, Ph.D., Asst. An. Nutri.
IY. S. Harrison, M.S., Asst. Agri. Engr.
F. T. Boyd, Ph.D., Asso. Agronomist
M. G. Hamilton, Ph.D., Asst. Horticulturist
J. N. Simons, Ph.D., Asst. Virologist
D. N. Beardsley, M.S., Asst. Animal Husb.
SUB-TROPICAL STATION, HOMESTEAD
Geo. D. Ruehle, Ph.D., Vice-Dir. in Charge
D. 0. Wolfenbarger, Ph.D., En'tomologist
Francis B. Lincoln, Ph.D., Horticulturist
Robert A. Conover, Ph.D., Plant Path.
John L. Malcolm, Ph.D., Asso. Soils Chemist
R. W. Harkness, Ph.D., Asst. Chemist
R. Bruce Ledin, Ph.D., Asst. Hort.
J. C. Noonan, M.S., Asst. Hort.
M. H. Gallatin, B.S., Soil Conservationist2
WEST CENTRAL FLORIDA STATION,
BROOKSVILLE
Marian W. Hazen, M.S., Animal Husband-
man in Charge
RANGE CATTLE STATION, ONA
W. G. Kirk, Ph.D., Vice-Director in Charge
E. M. Hodges, Ph.D., Agronomist
D. W. Jones, M.S., Asst. Soil Technologist
CENTRAL FLORIDA STATION, SANFORD
R. W. Ruprecht, Ph.D., Vice-Dir. in Charge
J. W. Wilson, ScD., Entomologist
P. J. Westgate, Ph.D., Asso. Hort.
Ben F. Whitner, Jr., B.S.A., Asst. Hort.
Geo. Swank, Jr., Ph.D., Asst. Plant Path.
WEST FLORIDA STATION, JAY
C. E. Hutton, Ph.D., Vice-Director in Charge
H. W. Lundy, B.S.A., Associate Agronomist
SUWANNEE VALLEY STATION,
LIVE OAK
G. E. Ri'chey, M.S., Agronomist in Charge
GULF COAST STATION, BRADENTON
E. L. Spencer, Ph.D., Soils Chemist in Charge
E. G. Kelsheimer, Ph.D., Entomologist
David G. A. Kelbert, Asso. Horticulturist
Robert O. Magie, Ph.D., Plant Pathologist
J. M. Walter, Ph.D., Plant Pathologist
S. S. Woltz, Ph.D., Asst. Horticulturist
Donald S. Burgis, M.S.A., Asst. Hort.
C. M. Geraldson, Ph.D., Asst. Horticulturist
FIELD LABORATORIES
Watermelon, Grape, Pasture-Leesburg
J. M. Crall, Ph.D., Associate Plant Path-
ologist Acting in Charge
C. C. Helms, Jr., B.S., Asst. Agronomist
L. H. Stover, Assistant in Horticulture
StrawLerry-Plant City
A. N. Brooks, Ph.D., Plant Pathologist
Vegetables-Hastings
A. H. Eddins, Ph.D., Plant Path. in Charge
E. N. McCubbin, Ph.D., Horticulturist
T. M. Dobrovsky, Ph.D., Asst. Entomologist
Pecans-Monticello
A. M. Phillips, B.S., Asso. Entomologist2
John R. Large, M.S., Asso. Plant Path.
Frost Forecasting-Lakeland
Warren O. Johnson, B.S., Meteorologist in
Charge
1 Head of Department
2 In cooperation with U. S.
a Cooperative, other divisions, U. of F.
SOn leave
CONTENTS
PAGE
CARE AND MANAGEMENT OF THE HERD .-.-...- -...-------..- ...-- ---- 5
DEVELOPMENT OF BOVINE FETUSES .~. ........-- ---..--..-.-....--- 5
AGE OF DAM AFFECTS WEIGHTS OF CALVES ........ -....-----------. ------.---. 7
LENGTH OF GESTATION AFFECTS BIRTH WEIGHTS ......................--..--... 9
SEX RATIO IN JERSEYS ... ..... .-- ---------- ...... -..... --------- ..----- 12
MULTIPLE BIRTHS .... ......-.. ....- ....--..-- -- --- 13
DISPOSAL OF HEIFER CALVES .. .............. ... ...........-..... .... ---- -- ---- 15
THE FLORIDA STATION HERD ................. ...--..--- -.--.. ---... -.--------. 17
CALVES PER DAIRY COW ..... ..... ........- .............--. ... ..----.-- .---- 18
SUMMARY .. .... ................. ............ .. .....- ....--. ---- 19
ACKNOWLEDGMENTS .. .. .... -.....................-... --................------ 20
LITERATURE CITED ...... ......-.. .. ......... ....... ..... -.....--.. -- --..----- --- ...---- 20
DAIRY CALVES
Their Development and Survival
P. T. Dix ARNOLD and R. B. BECKER
In the United States, as in Florida, large numbers of dairy
calves are raised annually to serve as replacements in dairy
herds. Despite this fact, some cows are imported into this
country from Canada each year. Fewer dairy calves were
raised between 1945 and 1950 than were needed to maintain
the cow population, and consequently the numbers of milking
cows dropped from over 24,000,000 to fewer than 22,000,000
head in 1952. Increasing demand for replacements encouraged
a change in the trend and resulted in a slightly more favorable
balance in the numbers of heifers coming toward producing
age. During this period dairy cattle numbers in Florida in-
creased steadily. The proportion of heifers raised has shown a
notable increase.
The reproductive rate among dairy cattle and the possibilities
of maintaining cow numbers with home-raised replacements
are important considerations. There is need for basic informa-
tion on these problems. One phase deals with calves born in
a herd, and the possibilities that they can grow and reproduce,
so as to become milking cows. More facts also are needed
concerning the calves as they develop, and the proportion of
male to female calves that can be expected normally.
A study of calving records has been made with the purebred
Jersey herd at the Florida Agricultural Experiment Station
during a period when the policy was to try to raise and retain
every heifer calf born alive. Some of the related factors have
been analysed for this phase of the study of dairy cattle breed-
ing.
Birth weights and chances of survival of dairy calves are
affected by several factors. Although most of these factors
are beyond control of the owner, knowledge of them will aid
in plans for, and management of, animals to be raised for dairy
replacements.
CARE AND MANAGEMENT OF THE HERD
Detailed records have been kept of dairy calves in the pure-
bred Jersey herd of the University of Florida Agricultural
DAIRY CALVES
Their Development and Survival
P. T. Dix ARNOLD and R. B. BECKER
In the United States, as in Florida, large numbers of dairy
calves are raised annually to serve as replacements in dairy
herds. Despite this fact, some cows are imported into this
country from Canada each year. Fewer dairy calves were
raised between 1945 and 1950 than were needed to maintain
the cow population, and consequently the numbers of milking
cows dropped from over 24,000,000 to fewer than 22,000,000
head in 1952. Increasing demand for replacements encouraged
a change in the trend and resulted in a slightly more favorable
balance in the numbers of heifers coming toward producing
age. During this period dairy cattle numbers in Florida in-
creased steadily. The proportion of heifers raised has shown a
notable increase.
The reproductive rate among dairy cattle and the possibilities
of maintaining cow numbers with home-raised replacements
are important considerations. There is need for basic informa-
tion on these problems. One phase deals with calves born in
a herd, and the possibilities that they can grow and reproduce,
so as to become milking cows. More facts also are needed
concerning the calves as they develop, and the proportion of
male to female calves that can be expected normally.
A study of calving records has been made with the purebred
Jersey herd at the Florida Agricultural Experiment Station
during a period when the policy was to try to raise and retain
every heifer calf born alive. Some of the related factors have
been analysed for this phase of the study of dairy cattle breed-
ing.
Birth weights and chances of survival of dairy calves are
affected by several factors. Although most of these factors
are beyond control of the owner, knowledge of them will aid
in plans for, and management of, animals to be raised for dairy
replacements.
CARE AND MANAGEMENT OF THE HERD
Detailed records have been kept of dairy calves in the pure-
bred Jersey herd of the University of Florida Agricultural
Florida Agricultural Experiment Stations
Experiment Station since establishment of the herd. Records
of gestation periods, sexes, and birth weights of normal calves
born between July 1929 and September 1950 have been analysed.
During this 21-year period the herd was maintained brucellosis-
free on an area near the campus of the University of Florida at
Gainesville. The herd was moved to the Dairy Research Unit
near Hague in September 1950. There the soils and environ-
mental conditions were different, so records obtained at the new
location were not used in the present analysis.
During the 21-year period mentioned the dairy animals were
on pastures grown largely on acid sand soils, with corn and
sorghum silages to supplement the pasture grasses. Limited
amounts of legume hays were purchased for supplemental use
and for special feeding trials. Mixed concentrates-fed in propor-
tion to milk and butterfat production-contained approximately
17 percent of total crude protein. One percent of common salt
and 2 percent of steamed bonemeal were added to the concen-
trates between January 1929 and January 21, 1938. At that
time one-half of the bonemeal was replaced by marble dust
("kalsite") as part of the supplemental calcium. The herd had
access to an iron-copper-salt mineral supplement since 1930, to
which a trace of cobalt was added continuously since late 1937.
The cattle had free access to these minerals in a divided mineral
box, as mentioned in Florida Agricultural Experiment Station
Bulletin 513 (4).1
DEVELOPMENT OF BOVINE FETUSES
Weights of bovine fetuses were observed whenever occasion
permitted, largely after slaughter of cows at the close of their
productive lifetime. A study of fetuses was presented earlier
in a brief technical report (5). Based on this report and later
records, with a total of 59 Jersey fetuses from 26 days to full
term, from the Station herd, average calculated weights of Jersey
fetuses have been interpolated by monthly intervals, as given
in Table 1.
The sex of a fetus less than 60 days in gestation seldom was
determined on casual macroscopic observation. Jersey fetuses
appeared, on the average, to attain a weight of about 1.0 pound
at about 3.5 months and about 12 pounds after six months ges-
tation. Increase in weight was rapid thereafter. Male fetuses
1 Italic figures in parenthesis refer to Literature cited.
Dairy Calves-Their Development and Survival
tended to outweigh female fetuses at corresponding ages by a
few grams at 90 days in gestation to over three pounds at full
term.
TABLE 1.-RELATION OF AGE AND SEX BASED UPON WEIGHTS OF 59 JERSEY
FETUSES FROM 26 DAYS IN GESTATION TO FULL TERM.
Age of Fetus Sex Unde- Male Female
Days termined
30 0.25 gms.
60 12.0 gms. 12.0 gms.
90 ......... 0.5 lbs. 0.5 Ibs.
120 ......... 1.9 lbs. 1.5 lbs.
150 ........ 5.7 lbs. 4.8 lbs.
180 .......... 12.0 lbs. 11.5 lbs.
210 -...... 21.0 lbs. 20.0 lbs.
240 ......... 40.0 lbs. 38.3 lbs.
270 i ........... 53.7 lbs. 48.8 lbs.
Full term ** ......... 55.2 lbs. 51.9 lbs.
Too few female fetuses had been obtained to safely interpolate this weight.
** The weights at full term are those computed for 421 male and 411 female Jersey
calves, following average gestation periods of 277.9 and 276.5 days, respectively.
With larger breeds, Kislovsky and Larchin (18) and Winters
et al (40) observed similar, but slightly larger, increases in
fetal weights at the corresponding age periods. The first
authors pointed out three periods of metamorphosis, at suc-
cessively lessened rates of increase in weight.
AGE OF DAM AFFECTS WEIGHTS OF CALVES
For the 21-year period for which calving records were
analysed, 832 calves were weighed that were born following
presumably normal gestation periods. Sex of each calf was
noted. The herd was maintained largely by home-raised re-
placements, hence many calves were first-born. Calf records
were grouped according to order of birth, up to the 13th calf
from one dam. These records were analysed as to range and
average weights and average gestation periods for males and
females respectively, as set forth in Table 2.
Average birth weights of first-born calves tended to be about
five or more pounds lighter than subsequent calves. Range in
birth weights among individuals within any group far exceeded
the differences in average weights between groups that com-
prised 10 or more individuals. The average weight of 421 males
was 55.2 and of females 51.9 pounds. These averages were in
TABLE 2.-RELATION
Order
of Number
Calving
1st
2nd
3rd
4th
5th
6th
7th
8th
9th
10th
11th
12th
13th
Total
or Ave.
2
1
1
421
OF ORDER OF CALVING, SEX AND GESTATION LENGTHS ON BIRTH WEIGHTS OF JERSEY CALVES DROPPED
BETWEEN JULY 1929 AND SEPTEMBER 1949.
Male Calves
Average
Gestation
Days
276.4
278.4
278.7
277.5
278.0
280.4
277.3
280.0
284.7
275.0
276.0
280.0
277.9
Birth
Range
Pounds
28 to 66
27 to 70
40 to 80
40 to 78
43 to 80
46 to 75
45 to 78
50 to 70
48 to 70
60 to 64
Weights
Average
Pounds
49.3
57.3
57.3
56.9
58.8
54.7
55.4
59.9
62.3
62.0
50.0
48.0
55.2
Number
Female Calves
Average
Gestation
Days
275.6
276.3
277.2
277.2
277.1
276.2
277.4
276.4
278.3
276.8
276.0
277.0
276.5
Birth Weights
Range Average
Pounds Pounds
20 to 73 47.5
36 to 72 53.4
40 to 69 54.7
37 to 68 53.9
42 to 67 54.0
46 to 64 55.1
34 to 65 54.4
38 to 64 50.6
44 to 60 51.0
46 to 55 50.0
........ 54.0
.-- 60.0
51.9
Dairy Calves-Their Development and Survival
close agreement with those observed for the breed by other in-
vestigators (7, 8, 29, 31).
LENGTH OF GESTATION AFFECTS BIRTH WEIGHT
Differences are recognized in length of gestation between
breeds of dairy cattle. Those with Ayrshires, Holstein-Friesians
and Jerseys are about the same length, while Brown Swiss are
longest and Guernseys intermediate, according to a study by
the Breeding Committee of the American Dairy Science Asso-
ciation. Average gestations suggested by them were:
Number of Average
Gestations Gestation Length
Ayrshire ......... .......................... 1,039 278.7 days
Brown Swiss ..................... 1,548 290.8 days
Guernsey .............................. ........ 576 284.0 days
Holstein .............. .. .......... 5,548 278.9 days
Jersey ....... ..................... 3,118 279.3 days
First gestations were about two days shorter than subse-
quent ones. Copeland (6) found that chances were about equal
in Jerseys for calves to be dropped from 271 to 285 days in
gestation, the average of 1,075 cases being 278.51 days. Males
were carried about one day longer than females, and twins
shorter than average. Fitch (9) and Olson (29) observed that
gestations of male calves were 1 to 3 days longer than females.
White and associates (37) confirmed these findings in a study
of 1,300 calvings at the Connecticut station. Of 1,063 normal
Guernsey calves at Boulder Bridge Farm, Minnesota (1), 554
male calves were carried an average of 285.61 days and 509
females for 283.34 days. Cows were inclined to carry longer
in the winter than at other seasons. There were 21 pairs of
twins.
At the Ohio station (19) 219 Holstein male calves were car-
ried 278.52 0.223 days and 213 females for 277.76 -- 0.211
days; 188 Jersey males for 279.25 0.267 days and 185 females
for 277.55 0.229 days. First calves of these breeds were
dropped 2.58 days and 2.63 days sooner than from six-year old
TABLE 3.-RELATION OF LENGTH OF GESTATION AND SEX ON BIRTH WEIGHTS OF JERSEY CALVES JULY 1929 TO SEPTEMBER 1949.
Gestation Male Calves
Period Number Range Average
Days Pounds Pounds
Under 260 2 48 to 62 55.0
262 2 42 to 48 45.0
263 2 36 to 50 43.0
264 1 ......-. 38.0
265 .. ..- -
266 3 40 to 63 51.0
267 6 38 to 50 42.7
268 5 41.5 to 58 53.1
269 2 41 to 45 43.0
270 8 40 to 80 53.6
271 8 48 to 66 53.2
272 15 42 to 64 52.3
273 21 41 to 69 55.7
274 20 40 to 68 50.0
275 36 32 to 71 53.8
276 33 31 to 70 52.7
277 32 28 to 66 54.2
278 34 40 to 73 55.6
279 25 30 to 71 55.6
280 35 48 to 75 58.3
281 21 46 to 70 57.7
282 25 40 to 70 55.9
283 29 44 to 74 58.4
284 14 47 to 80 59.8
285 15 37 to 72 60.3
286 8 49 to 78 67.1
287 3 38 to 60 52.0
288 6 39 to 68 53.5
289 4 45 to 68 58.8
Above 290 6 52 to 74 59.5
--.. ........-....... 421
Female Calves
Number Range
Pounds
2 42 to 54
3 45 to 52
4 36 to 52
2 42 to 44
1 ..
4 41 to 62
9 35 to 58
16 38 to 66.5
15 34 to 60
23 40 to 58
20 34 to 63
27 30 to 67
43 20 to 64
33 30 to 76
33 46 to 73
36 42 to 62
33 43 to 69
29 42 to 65
24 35 to 68
14 40 to 64
15 36 to 64
11 46 to 66
4 54 to 66
4 42 to 60
1
4 35 to 63
1
1 ........
411
Average
Pounds
48.0
49.3
43.8
43.0
27.0
47.3
45.4
47.7
46.4
49.9
50.4
49.8
51.7
53.5
54.5
52.9
53.4
54.3
53.7
54.4
55.6
52.8
58.8
54.5
45.5
49.5
60.0
Total
Dairy Calves-Their Development and Survival 11
cows, on the average. Knott (20) reported 1,441 Holstein males
carried 280.4 0.090 days and 1,383 females for 279.4 0.087
days, the difference being significant statistically. He noted that
gestation periods of calves sired by some bulls were definitely
longer or shorter than the average, indicating a possible pa-
ternal influence.
At the Michigan station (2) 70 percent of 148 Brown Swiss
calves were dropped between 285 and 297 days, averaging 291
days in gestation. No difference was reported due to sex of calf.
In a few instances calves in the Florida station herd were not
weighed soon enough after birth for their weights to be used.
A few cases occurred in which there was doubt as to a service
date resulting in conception. There were 421 males and 411
females with records usable to study gestation lengths.
The relation of length of gestation period and sex on the
birth weights of Jersey calves was analysed, as shown in Tables
3 and 4.
TABLE 4.-RELATIONSHIP BETWEEN BIRTH WEIGHTS, SEX AND GESTATION
PERIODS WITH JERSEY CALVES.
Male Calves Female Calves
Birth Weights Average -Average
Number Gestation Number Gestation
Pounds Days IDays
Under 30 2 277.0 4 273.0
31 to 35 3 272.7 6 275.5
36 to 40 19 274.6 i 22 272.4
41 to 45 31 275.2 41 274.1
46 to 50 68 275.8 101 276.4
51 to 55 86 278.3 106 276.3
56 to 60 109 278.5 80 278.1
61 to 65 53 278.8 37 1 278.6
66 to 70 34 281.0 12 278.7
71 to 75 12 281.7 1 277.0
76 to 80 4 281.8 1 276.0
Average ......... 421 277.9 411 276.5
Four apparently normal calves were born alive following
gestation periods of 260 days or less. Seven calves also were
born following gestations of 290 days or longer. In these in-
stances no other accountable service dates were on record.
Among the bull calves dropped earlier than 270 days in ges-
tation there appeared to be a significant tendency for their birth
weights to be lighter than average for groups carried longer
Florida Agricultural Experiment Stations
intervals by their dams. The tendency was less marked among
heifer calves. The general trend toward increased average
weights occurred somewhat alike among male and female calves
carried 270 to 279 days. The longer gestations tended to result
in heavier calves (see Tables 3 and 4). The wide range between
weights of individual calves of either sex carried for any par-
ticular gestation period was extremely noticeable. This wide
range would make weight alone quite unpredictable as a basis
for estimating gestation length.
The average gestation for Jersey males was computed to be
277.9 days, as compared with 276.5 days for female calves. The
gestation periods at first calving averaged one to three days
shorter than at subsequent calvings.
SEX RATIO IN JERSEYS
The sex of Jersey fetuses was determined macroscopically
when sufficiently developed. There were 8 fetuses of undeter-
mined sex, 31 male and 20 female fetuses. Combined with 430
male and 412 female calves (including a few of uncertain ges-
tation period or premature births), these totaled 461 males and
432 females over a 21-year period. This proportion indicated a
sex ratio in single births of Jerseys in the Florida station dairy
herd of 51.6 percent of males to 48.4 percent of females. This
is in reasonable agreement with the sex
in dairy cattle previously, as follows:
Proportion of
Males
52.1 percent
51.48 percent
48.3 percent
48.6 percent
51.12 percent
50.5 percent
53.1 percent
53.3 percent
52.8 percent
51.45 percent
50.6 percent
51.0 percent
50.1 percent
46.7 percent
49.4 percent
49.9 percent
ratios at birth observed
Citation
Anonymous (1)
Davis (7)
Eckles (8)
Fitch, et al (9)
Gilmore (10)
Gowen (12)
Hilder, et al (13)
Hull, et al (14)
Ingals and Cannon (15)
Johansson (16)
Knoop and Hayden (19)
Knott (20)
Lovell and Hill (23)
Olson (29)
Seath, et al (33)
Wing (39)
Number of
Calves
1,063
2,362
433
521
197,936
3,559
3,442
1,060
1,347
124,000
805
2,824
23,103
771
881
644
Dairy Calves-Their Development and Survival
MULTIPLE BIRTHS
During the 21-year period 18 twin births occurred among
912 calvings or fetuses in the station Jersey herd. Fourteen
followed apparently normal gestation periods. Eight pairs were
male calves, five pairs were females and five pairs were mixed
twins. One set of triplets-all females-were dropped prema-
turely (250 days) and died. The records of multiple births are
presented in Table 5.
TABLE 5.-BIRTH WEIGHTS, SEXES AND GESTATION LENGTHS OF MULTIPLE
BIRTHS IN JERSEYS.
Order of I Gesta- I Total
Calving tion Days Sex Weight Sex Weight Weight
Pounds Pounds Pounds
Second 267 Male 49 Male 39 88
Second 267 Male 40 Male 38 78
Second 277 Male 46 Male 50 96
Third 255* Male* 30 Male* 35 65
Third 269 Male 48 Male 50 98
Fourth 276 Male 42 Male 42 84
Fourth 267 Male 40 Male 42 82
Fifth ....* Male .... Male
First 278 Male 48 Female 46 94
Second 270 Male 46 Female 40 86
Second ......* Male* 25 Female* 15 40
Fourth 270 Male 43 Female 43 86
Fifth 265 Male 52 Female 42 94
Second .....* Female* 5 Female* 3 8
Third 268 Female 48 Female 52 100
Third 271 Female 52 Female 38 90
Third 272 Female 40 Female 35 75
Third 272 Female 52 Female 52 104
Third 250* Female* 32
Female* 30
Female* 26. ......... ........ .... ... ......... 88
Apparently premature; dead when found.
The four living females born twin with a bull were free-
martins, as verified anatomically. They were sexually abnormal
and presumed incapable of reproduction. Swett and associates
(35) noted varying degrees of failure of internal genitals to
develop in freemartins. Often the clitoris was enlarged. Some-
times the udder was smaller than normal and contained a high
Florida Agricultural Experiment Stations
proportion of fatty to glandular tissue. These are some of the
means for early diagnosis of the freemartin condition in the
female of mixed twins.
Gestation periods for 14 sets of apparently normal Jersey
twins averaged 270.6 days in length, the range being between
265 and 278 days. This was six to seven days shorter than
average gestations of males and females born singly.
Individual weights and total weights of twin calves are listed
in Table 5. Total weights of these sets of apparently normal
multiple births ranged between 78 and 104 pounds per set and
averaged 44.8 pounds per individual animal. Weights of several
twin heifer calves were as much as those of average individuals
born singly.
Among the Florida Jerseys twin births (Table 6) amounted to
1.97 percent, which was within the range expected ordinarily in
dairy cattle; but triplets or higher multiple births have been
extremely scarce in this species.
TABLE 6.-FREQUENCIES OF SINGLE AND MULTIPLE CONCEPTIONS OBSERVED
IN A JERSEY HERD DURING A 21-YEAR PERIOD.
From
Normal Partial Total Percentage
Calves Gestations Gestations
Single births 842 51 893 97.92
Twins .............. 14 4 18 1.97
Triplets ........... .... 1 1 0.11
Total .......... 912 100.00
Wing (38) observed 2.5 percent of twin births in Holsteins.
Two females among six pairs of mixed twins were fertile and
reproduced. There are other infrequent instances of the female
of mixed twins being normal sexually and reproducing. In com-
mercial herds it usually is not practical to raise the female of
mixed twins for breeding purposes.
Lush (24) found a marked difference between sires in the
frequency of twins among Holsteins at the Kansas station and
concluded that the tendency toward twinning may be heredi-
tary. Tabulation of 494 sets of twins among 15,039 calvings
indicates an average of 3.04 percent twins among four dairy
breeds (see Table 7).
Dairy Calves-Their Development and Survival
TABLE 7.-PROPORTION OF TWINS AMONG TOTAL BIRTHS OF DAIRY CATTLE.*
All
Ayr- Guern- Hol- Jerseys Dairy References
shires seys steins Breeds
21-1,063 ....... .... ....... Anonymous (1)
18x-911 ...... Florida data
16-364 13- 364 30- 977 7 -657 .... Davis (7)
-.-.-. .-- 21-2,573 Gowen (11)
--- ... 86-2,910 ....... ...... Knott (20)
3- 68 2- 165 20- 466 2x 174 ....... Lamb (21)
2-125 3- 111 16- 197 1 98 ....... Lush (24)
....... .......... 21 689 M iller (28)
-...-.-...-.... .. 20- 1,165 Miller and
Gilmore (27)
........ 17-1,300 W hite (37)
-.-.-.- 16- 630 ....... ........ W ing (39)
Grand Total ............................... 494- 15,039 (3.04% )
The first numerals are the numbers of sets of twins. The second numerals are the
total calvings.
x Two sets of triplets among Jerseys were excluded.
The frequency of 0.11 percent for Jersey triplets was regarded
as far higher than would be expected among dairy cattle. Jones
and Rouse (17) computed from volumes 1- 26 of the Aberdeen
Angus Herd Book and volumes 1 42 of the Hereford Herd Book
that there was one living set of triplets among 109,600 Angus and
one among 105,580 Herefords registered. The tendency for
multiple births is assumed to be higher among dairy breeds than
among these beef breeds.
DISPOSAL OF HEIFER CALVES
The ultimate prospects of a calf entering the herd as a breed-
ing and milking cow is dependent on several conditions-in-
cluding live-birth, calfhood mortality, later death and failure of
conception among older heifers. Records contributing to this
phase of the investigation began with heifers in the Florida
station Jersey herd during January 1929 and included animals
about two years old by September 1949. Numbers of animals
involved in this phase of the study, therefore, differ from those
concerned with birth weights, gestation lengths and sex ratio.
The policy of herd management was to raise all heifers possible
to become herd replacements.
Similar studies have been made in other places as to the possi-
bilities of heifer calves becoming cows in the milking herd.
Ormiston (30) of Illinois reported six percent still-births and
24 percent further losses under one year of age of calves born
Florida Agricultural Experiment Stations
normally. About three-fourths of these losses occurred under
60 days of age, pneumonia being a major cause. Miller and
Gilmore (27) of Minnesota reported 8 percent of calves born
dead and 23 percent more died in one herd before six months
old. In another Minnesota herd 6 percent of calves were born
dead and 12 percent more died before six months of age. Savage
and McCay (32) stated that calf losses were severe during
early life. They cited losses of 23, 28 and 23.65 percent in
three dairy herds.
Weaver, Horwood and Smiley (36) of Michigan reported
losses amounting to 13.7 percent among calves up to 10 months
of age. Of these losses, 44.6 percent were during the first month,
25 percent in the second month, 11.5 percent in the third month
and 18.9 percent from the 4th to the 10th months. Recently
Davis (7) analysed records of 1,178 heifer calves born in the
Nebraska station herd over a 45-year period. Some 9.25 percent
were dead or died at birth, while 13.66 percent were lost because
of disease and 11.5 percent were disposed of otherwise. Of 1,069
heifers born alive, 67.92 percent were retained in the herd to
two years of age.
Wing (39) summarized records of the Holstein herd at Cornell
University from 1889 to 1928 and reported that 7.5 percent of
calves were born dead, 11.0 percent were aborted and 9.5 percent
died under three months. Of 232 heifers raised, 3.0 percent
Fig. 2.-Luxuriant, well-fertilized pastures of legumes and grasses encourage
rapid growth and development of yearling heifers.
Dairy Calves-Their Development and Survival
died between three months old and breeding age and two heifers
were barren.
THE FLORIDA STATION HERD
Heifer calves were placed in individual bedded pens soon after
birth. Colostrum milk from the dam was given each calf. The
calves received whole milk until about six weeks of age, and
either re-constituted skimmilk or a dry mix containing some
skimmilk powder. Calves were encouraged to eat hay and
concentrates as early as possible and placed on pasture later,
where mineral supplements (4) always were available. Hay and
corn or sorghum silage were supplied when needed, along with
limited concentrates to encourage rapid growth.
Over the 20-year period studied in this problem, 408 Jersey
heifer calves were born in the Florida Agricultural Experiment
Station dairy herd. Stillborn heifers or those which died at
birth amounted to 4.9 percent and freemartins to 1.2 percent.
Living heifer calves lost under six months of age accounted for
12.2 percent (see Table 8), while an additional 6.9 percent died
later and never entered the milking herd. Failure to conceive
caused disposal of 9.6 percent of the total number. Nineteen
animals in this group were assigned to experimental work when
past two years of age, following unsatisfactory breeding his-
tories in varying degrees, yet not all of them could be classed
as barren or sterile. Twenty other heifers failed to conceive
following repeated breeding and veterinary treatment and were
slaughtered. Postmortem examinations of the reproductive or-
gans showed little possibility that conception could have oc-
curred.
During this period the herd had been continuously free of
tuberculosis and brucellosis. Losses of young calves were due
principally to scours, coccidiosis and pneumonia, while other
diseases caused most of the losses among heifers past six months
of age. A summary of losses of heifer calves from all causes is
presented in Table 8.
If losses of heifer calves could be minimized and if fewer
heifers failed to conceive, the proportion of heifers required
to be raised for replacements would be reduced. Reduced losses
would permit closer culling of cows and would result in a higher
quality dairy herd. There is a demand for surplus heifers of
desirable quality for use in replacement of other herds.
18 Florida Agricultural Experiment Stations
TABLE 8.-LossES OF JERSEY HEIFERS FROM ALL CAUSES BETWEEN
1929 AND 1949.
Number Percent
Losses:
Stillborn, or died at birth .. ... ... .... ...... 20 4.9
Freem artins ...... ..........- .. ..- ...... .... 5 1.2
Living calves lost under six months of age:
Scours and Coccidiosis .................- ..........- 15
Diseases .............................. .. ......... 16
Unknown ......................... ... ............. .. 12
Weak at birth (died within 10 days) .. .. 6
A accident ....................... ....... ...... ..... .... 1
50 12.2
Living heifers lost after six months of age:
Disease and disease suspect ................ 15
A accidents ................ ........ -- .. ... ....- 5
U nknow n ...-....... .............. ..-. .. ..--.... 3
Poison, bloat, deformed ...... ... ................. 3
Scours ....... --......... -.... .... .... .... ... .. .. 2
28 6.9
Failure to conceive .......... ................. 39 9.6
Total Losses .......... ................. .... .. .... 142 34.8
Females that conceived and freshened .........- 266 65.2
Total ..... ........ .... .... ..-..- ......... 408 100.0
Included are 19 heifers with varying unsatisfactory breeding histories, consigned to
experimental work after two years of age but not necessarily sterile or barren.
CALVES PER DAIRY COW
Tabulation of the completed reproductive histories of 249
Jersey cows in the station herd showed 919 calves at single
births, 450 of which were heifers. There were 16 pairs of twins,
including three pairs of females and six freemartin heifers. In-
cluding the latter, there were 1.86 females per average cow's
reproductive life. If 65.2 percent of heifers born entered the
milking herd, this would allow replacement of 249 cows with
301 milking progeny, or 1.21 females per dam. This is a slow
rate of increase, considering that every living heifer calf was
intended for replacement.
A study of life-span of dairy cows of known ages raised in
Florida (3) disclosed that the period of usefulness after first
calving averaged 4.1 years. The average productive life was
between two and three years in herds that purchased replace-
ment of unknown age.
Dairy Calves-Their Development and Survival
McDowell (26) tabulated over 10,000 yearly records from
Dairy Herd Improvement Associations and found that cows
remained in dairy herds an average of 4.7 years. Larson (22)
computed that 4.85 years was the average productive life of
cows in New York Dairy Herd Improvement Associations. Spill-
man (34) compared the useful life of dairy cows after calving
in Pennsylvania as 4.34 years, where 37 percent were home-
raised, with 4.52 years in Michigan and with 57 percent of
them home-raised. Lush (25) found this period to be 3.5 years
in Iowa herds under commercial conditions.
Cows usually do not produce one calf per year, on the average.
The calving interval in the Iowa State College herd (15) was
found to be 446 days on the average, as compared with 424 days
in a brucellosis-free herd in Illinois (41). With calving intervals
of these lengths, there can be only three or four calves dropped
during the productive lifetime of the average cow.
Natural increase in size of dairy herds proceeds slowly. Lim-
iting factors are the average productive life-span of cows, in-
tervals between calvings, ratio of heifer to bull calves, death
losses and sterility among calves and heifers. Some increases
could be attained by lengthening productive life of dairy cows,
calving at shorter intervals, and reduction of losses due to calf
mortality and failure to breed.
SUMMARY
The growth rate of male Jersey fetuses was slightly faster
than that of females, from 90 days to full term.
The first calves dropped by Jersey heifers usually weighed
about five pounds less than subsequent calves. Only at ex-
tremely advanced age of dams was there any tendency for a
decline in average birth weights of calves.
Average lengths of gestation periods were 277.9 days for 421
males and 276.5 days for 411 female Jersey calves. Generally,
calves with light birth weights were carried for shorter gesta-
tion periods than were heavier calves. Also, male calves born
following short gestation periods were slightly lighter on the
average than those carried from 270 to 285 days. However,
ranges in birth weights and gestation lengths were wider with-
in groups than were the differences between groups. Weight
alone is unpredictable as a basis for estimating gestation
lengths.
Florida Agricultural Experiment Stations
The sex ratio of Jerseys over a 21-year period in the station
herd (considering all identified fetuses and calves) was 51.6 per-
cent of males among 893 individuals.
Fourteen pairs of normal twins were carried 270.6 days (265
to 278 days) on the average. Birth weights of some twin
heifer calves were as high as the average birth weight for single
births. There were 1.97 percent of twin births, and a single
(0.11 percent) instance of triplets among 912 known concep-
tions. This frequency of triplets is above the normal expectancy
in dairy cattle.
Of 408 heifer calves born during 20 years, 4.9 percent were
stillborn or died at birth. Losses under six months of age from
scours, coccidiosis, diseases, weakness at birth, etc., amounted to
12.2 percent, with 1.2 percent being freemartins.
Losses past six months of age from diseases, accidents, bloat,
etc., totaled 6.9 percent. Failure to conceive and difficult breed-
ing eliminated 9.6 percent of older heifers.
Where the policy was to raise every heifer calf, 65.2 percent
of those born entered the milking herd eventually. From 249
cows 301 replacements were obtained, or an average of 1.21
females per dam.
A reduction of calf and heifer losses would allow faster in-
crease in herd numbers. With larger numbers, culling could be
practiced that would result in a herd of higher quality.
ACKNOWLEDGMENTS
Appreciation is expressed to the late Clarence M. Robinson, Burdette
Schee and Herman Somers, who served as herdsmen during parts of this
period. Many student helpers and others cooperated in maintaining
accurate records of the dairy herd at the Florida Agricultural Experiment
Station during the years covered in this publication. Photographs used
with this publication were taken by Jasper Joiner of the Editorial De-
partment.
LITERATURE CITED
1. ANONYMOUS. Calving periods. Hoard's Dairyman 90: 333. June 10,
1945.
2. ANONYMOUS. 291 days length of Brown Swiss gestation found in re-
cent study. Brown Swiss Bulletin 26 (8) : 12. Feb., 1948.
3. ARNOLD, P. T. DIX, R. B. BECKER and A. H. SPURLOCK. Management of
dairy cattle in Florida. Fla. Agr. Exp. Sta. Bul. 464: 4-56. 1949.
4. BECKER, R. B., P. T. Dix ARNOLD, W. G. KIRK, GEORGE K. DAVIS and
R. W. KIDDER. Minerals for dairy and beef cattle. Fla. Agr. Exp.
Sta. Bul. 513: 4-51. 1953.
Florida Agricultural Experiment Stations
The sex ratio of Jerseys over a 21-year period in the station
herd (considering all identified fetuses and calves) was 51.6 per-
cent of males among 893 individuals.
Fourteen pairs of normal twins were carried 270.6 days (265
to 278 days) on the average. Birth weights of some twin
heifer calves were as high as the average birth weight for single
births. There were 1.97 percent of twin births, and a single
(0.11 percent) instance of triplets among 912 known concep-
tions. This frequency of triplets is above the normal expectancy
in dairy cattle.
Of 408 heifer calves born during 20 years, 4.9 percent were
stillborn or died at birth. Losses under six months of age from
scours, coccidiosis, diseases, weakness at birth, etc., amounted to
12.2 percent, with 1.2 percent being freemartins.
Losses past six months of age from diseases, accidents, bloat,
etc., totaled 6.9 percent. Failure to conceive and difficult breed-
ing eliminated 9.6 percent of older heifers.
Where the policy was to raise every heifer calf, 65.2 percent
of those born entered the milking herd eventually. From 249
cows 301 replacements were obtained, or an average of 1.21
females per dam.
A reduction of calf and heifer losses would allow faster in-
crease in herd numbers. With larger numbers, culling could be
practiced that would result in a herd of higher quality.
ACKNOWLEDGMENTS
Appreciation is expressed to the late Clarence M. Robinson, Burdette
Schee and Herman Somers, who served as herdsmen during parts of this
period. Many student helpers and others cooperated in maintaining
accurate records of the dairy herd at the Florida Agricultural Experiment
Station during the years covered in this publication. Photographs used
with this publication were taken by Jasper Joiner of the Editorial De-
partment.
LITERATURE CITED
1. ANONYMOUS. Calving periods. Hoard's Dairyman 90: 333. June 10,
1945.
2. ANONYMOUS. 291 days length of Brown Swiss gestation found in re-
cent study. Brown Swiss Bulletin 26 (8) : 12. Feb., 1948.
3. ARNOLD, P. T. DIX, R. B. BECKER and A. H. SPURLOCK. Management of
dairy cattle in Florida. Fla. Agr. Exp. Sta. Bul. 464: 4-56. 1949.
4. BECKER, R. B., P. T. Dix ARNOLD, W. G. KIRK, GEORGE K. DAVIS and
R. W. KIDDER. Minerals for dairy and beef cattle. Fla. Agr. Exp.
Sta. Bul. 513: 4-51. 1953.
Dairy Calves-Their Development and Survival 21
5. BECKER, R. B., P. T. DIX ARNOLD and SIDNEY P. MARSHALL. Changes
in weights of the reproductive organs of the dairy cow and their
relation to long-time feeding experiments. Jour. Dairy Sci. 33: 911-
917. 1950.
6. COPELAND, L. Length of gestation in Jersey cows. Jour. Dairy Sci.
13: 257-265. 1930.
7. DAVIs, H. P. Dairy calf births and disposals. Nebr. Agr. Exp. Sta.
Bul. 411: 3-22. 1952.
8. ECKLES, C. H. Dairy Cattle and Milk Production. 2nd edit. 1923.
Page 237. The Macmillan Company.
9. FITCH, J. B., P. C. MCGILLIARD and G. M. DRUMM. A study of the
birth weight and gestation of dairy animals. Jour. Dairy Sci.
7: 222-233. 1924.
10. GILMORE, L. A. Dairy Cattle Breeding. 1952. Pages 105-108. J. B.
Lippincott Company.
11. GOWEN, J. W. Report of progress in animal husbandry investigations
in 1917. Me. Agr. Exp. Sta. Bul. 274: 205-228. 1918.
12. GOWEN, J. W. On the sex ratio in cattle. Jour. Hered. 33: 299-301.
1942.
13. HILDER, R. A., M. H. FOHRMAN and R. R. GRAVES. Relation of various
factors to the breeding efficiency of dairy animals and to the sex ratio
of the offspring. Jour. Dairy Sci. 27: 981-992. 1944.
14. HULL, F. E., W. W. DIMMOCK, F. ELY and H. B. MORRISON. Reproduc-
tive efficiency in dairy cattle. Ky. Agr. Exp. Sta. Bul. 402: 161-
188. 1940.
15. INGALS, J., and C. Y. CANNON. The mortality of calves in the Iowa
State College dairy herd. Amer. Soc. Anim. Prod. Proc. 1936: 223-
229.
16. JOHANSSON, IVAR. Johansson's conclusions on sex ratio. Jersey Bul.
51 (10) : 332. March 19, 1932.
17. JONES, S. V. H., and J. E. ROUSE. I. Multiple births in cattle and sheep.
Jour. Dairy Sci. 3: 260-290. 1920.
18. KISLOVSKY, D. A., and B. A. LARCHIN. The period of embryonic growth
in cattle. Jour. Agr. Sci. (England) 21: 659-668. 1931.
19. KNOOP, C. E., and C. C. HAYDEN. A study of the length of gestation and
service record of dairy cows. Ohio Agr. Exp. Station Bimo. Bul.
19, No. 166: 8-14. Jan.-Feb., 1934.
20. KNOTT, J. C. A study of the gestation period of Holstein-Friesian
cows. Jour. Dairy Sci. 15: 87-98. 1932.
21. LAMB, L. W. Multiple births in dairy cattle. Mich. Agr. Exp. Sta.
Quart. Bul. 17: 185-189. May 1935.
22 Florida Agricultural Experiment Stations
22. LARSON, C. W. Milk Production Cost and Accounts, Principles and
Methods. Columbia University Press. 1916.
23. LOVELL, R., and A. BRADFORD HILL. A study of the mortality of calves in
335 herds in England and Wales (together with some limited ob-
servations for Scotland). Jour. Dairy Res. 11: 225-242. 1940.
24. LUSH, R. H. Inheritance of twinning in a herd of Holstein-Friesian
cattle. Jour. Hered. 16: 273-279. 1925.
25. LusH, J. L., and M. D. LACY. The ages of breeding cattle and the pos-
sibilities of using proved sires. Iowa Agr. Exp. Sta. Bul. 290: 34-78.
1932.
26. McDowELL, J. C. Dairy herd improvement associations and stories the
records tell. U. S. Dept. Agr. Farmers' Bul. 1604: 1-20. 1929.
27. MILLER, K., and L. GILMORE. Calf mortality, sex ratio and incidence
of twins in two University of Minnesota herds. Jour. Dairy Sci.
32: 706-707. 1949.
28. MILLER, F. W., R. R. GRAVES and M. H. FOHRMAN. Management and
breeding data on a dairy herd in which Bang's disease (infectious
abortion) was eradicated by segregation. Jour. Dairy Sci. 20: 537-
550. 1937.
29. OLSON, T. M. Elements of dairying. Revised ed. 1950. Page 160.
The Macmillan Company.
30. ORMISTON, E. E. Calf losses in a dairy herd consisting of five breeds.
Jour. Dairy Sci. 32: 712. 1949.
31. RAGSDALE, A. C. Growth standards for dairy cattle. Mo. Agr. Exp.
Sta. Bul. 336: 2-12. 1934.
32. SAVAGE, E. S., and C. M. McCAY. The nutrition of calves: A review.
Jour. Dairy Sci. 25: 595-650. 1942.
33. SEATH, D. M., C. H. STAPLES and E. W. NEASHAM. A study of breed-
ing records in dairy herds. La. Agr. Exp. Sta. Bul. 370: 3-19. 1943.
34. SPILLMAN, W. J., H. M. DIXON and G. A. BILLINGS. Farm management
practice of Chester County, Pa. USDA Bul. 341: 1-99. 1916.
35. SWETT, W. W., C. A. MATTHEWS and R. R. GRAVES. Early recognition
of the freemartin condition in heifers twinborn with bulls. Jour.
Agr. Res. 61: 587-623. 1940.
36. WEAVER, EARL, R. E. HORWOOD and E. S. SMILEY. Losses of calves in
dairy herd. Mich. Agr. Exp. Sta. Quart. Bul. 32 (1) : 42-47. Aug.,
1949.
37. WHITE, G. C., L. F. RETTGER and J. G. McALPINE. Infectious abortion
(fifth report). Storrs Agr. Exp. Sta. Bul. 123: 281-303. 1924.
38. WING, H. H. The period of gestation in cows. Cornell Univ. Agr.
Exp. Sta. Bul. 162: 323-334. 1889.
Dairy Calves-Their Development and Survival 23
39. WING, H. H. The Cornell University dairy herd, 1889-1928. Cornell
Univ. Agr. Exp. Sta. Bul. 576: 3-64. 1933.
40. WINTERS, L. M., W. W. GREEN and R. E. COMSTOCK. Prenatal develop-
ment of the bovine. Minn. Agr. Exp. Sta. Tech. Bul. 151: 3-50.
1942.
41. YAPP, W. W., and A. F. KUHLMAN. Breeding results in a herd of
cattle infected with contagious abortion. Amer. Soc. Anim. Prod.
Proc. 1932: 277-281. 1933.
|
