Page images
PDF
EPUB
[blocks in formation]

3.1

VARIATION IN FIRST YEAR EGG PRODUCTION

ANALYSIS OF STORRS DATA
COMPARISON WITH OTHER DATA

36

+1 16

MEAN PRODUCTION

VARIATION CONSTANTS

[ocr errors]

GENERAL TREND OF EGG PRODUCTION THROUGH THE MIXE

YEARS

[ocr errors]

CHANGES IN MEAN
CHANGES IN VARIABILITY
CHANGES IN PROPORTIONS OF HIGH AND LOW PRODUCING

FOWLS
CHANGES AT OTHER PLACES

51 JS

59

THE SEASONAL DISTRIBUTION OF EGG PRODUCTION
GENERAL CHARACTER OF EGG PRODUCTION IN THE SEPAR-

ATE MONTHS
MONTHLY MEANS
MONTHLY VARIABILITIES

59

60

63

EGG PRODUCTION IN THE FOUR MAJOR SEASONS

WINTER

SPRING

PAGE

65 67 72 73 74 74

SUMMER

AUTUMN
ANALYSIS OF EGG PRODUCTION IN SEPARATE MONTHS

GENERAL CHANGES IN SEASONAL DISTRIBUTION OF EGG

PRODUCTION
CHANGES IN THE SEPARATE WINTER MONTHS
SUMMARY

76 81

21

LIST OF FIGURES

Fig. 1. Variation in annual egg production; nine year's rec

ords. Fig. 2. Changes in mean annual egg production from 1911

to 1919. Fig. 3. Annual changes in the coefficient of variation from

1911 to 1919. Fig. 4. Annual changes in the percentage of pullets laying

104 eggs per year and less. Fig. 5. Annual changes in the percentage of pullets laying

210 eggs per year and more. Fig. 6 Monthly variation in mean egg production, nine years

records. Fig. 7. Comparison of low and high producing pullets on

the basis of monthly distribution of egg production. Fig. 8. Changes in the proportion of winter to annual egg

production 1911-1919.

LIST OF TABLES

Table 1. Frequency distribution of all Wyandotte pullets

on basis of annual egg production. Table 2. Summary of variation constants for annual egg

production. Table 3. Constants of variation in first year egy production

of Wyandottes at other places. Table 4. Relative frequency of low and high producers in

the nine contests. Table 5. Distribution of total ere production by months and

years. Table 6. Percentage distribution of total egy production by

months and years. Table 7. Summary of monthly variation constants. Table 8. Monthly variation in the efficiency of erg produc

tion, nine year mean. Table 9. Monthly distribution of total egg production by

fecundity classes, nine year's records. Table 10. ('omparison of low, medium, and high producing

pullets on the basis of monthly distribution of egg

production. Table 11. Percentage of flock laying zero eggs in the separ

ate months. Table 12. The seasonal listribution of egg production by

years. Table 13. General trend of seasonal distribution of egg pro

duction, 1911-1920. Appendix Table I. Raw data for annual egg production of

Wyandotte pullets. Appendix Table II. Frequency distribution of egg produc

tion in each month of the pullet year. Appendix Table III. Table for estimating significance of difThis is the first of a series of reports on egg production in the four chief breeds of poultry raised and kept in this country for egg production.

ferences between annual means.

The material studied consists of the individual trap nest records of all pullets completing a normal year's laying in the first nine international egg laying competitions held at Storrs Agricultural Experiment Station, Connecticut from November 1, 1911 to October 29, 1920. This and other bulletins to be published in this series will, therefore, constitute a summary of egg production in the nine contests, and will present the conclusions drawn from a detailed study of the records.

The main facts established from a study of 903 Wyandotte records are:

1. Average egg production for the pullet year-159.3 eggs. 2. Average winter egg production

(Nov. 1 to Feb. 28) 35.8 eggs. 3. Average spring egg production

(Mar. 1 to May 31) 53.8 eggs.
4. Average summer egg production

(June 1 to Aug. 31) 45.8 eggs.
5. Average autumn egg production

(Sept. 1 to Oct. 30) 24.1 eggs. 6. Highest individual year's record-308 eggs. 7. Lowest individual year's record–0 eggs. 8. Variability in individual egg production has remained

high throughout the nine contests. (The coefficient of

variation for the nine years was 28 per cent). 9. Average egg production has increased by about 7 eggs

from 1911 to 1920. 10. The percentage of annual production occurring in the

winter months has increased on the average by about

8 per cent. 11. The relative intensities of spring. summer, and autumn

production have declined by a similar amount. 12. The percentage of high producers (birds laying 210 eggs and over) has increased slightly in the nine years. 13. The. percentage of low producers (birds laying 104

eggs and under) has decreased slightly in the nine

years. 14. These tendencies toward improvement in the breed

are more marked if two years of abnormal conditions

and low records (1913 and 1918) are omitted. 15. There is no evidence in the records of separate seasonal

cycles of egg production in this breed. 16. The improvement of the Wyandotte breed as egg pro

ducers has been more rapid in England and the British Colonies and Dominions than in the United States.

« PreviousContinue »