PART I. FACTORS AFFECTING EGG WEIGHT IN THE
DOMESTIC FOWL.S.C. White Leghorn and White Wyandotte pullets
housed behind ordinary glass and not given adequate
amounts of vitamin D gave significantly lower
average egg weights than comparable pens given adequate
quantities of the anti-rachitic vitamin. The
egg size was not significantly less in the irradiated
ergosterol pen than it was in the cod liver oil pen.
There was no significant difference in the
egg weights for lighted and unlighted pens of Single
Comb White Leghorn pullets.
An all-in-one ration in pellet form gave
significantly larger egg size than the same ration in
mash form for both pullets and yearlings of the White
Leghorn breed.
Under the conditions of the experiment, both
green food and oyster shell proved of value in increasing
egg size when supplementing "All in one" rations.
Fish meal proved definitely of greater value
for egg size than decorticated extracted earth nut
meal (peanut meal) and was slightly more valuable than
extracted soya bean meal or meat meal.
A mineral supplement did not materially increase
the egg size when used with a meat meal ration,
unlimited oyster shell being available.
When a standard ration was fed to Cuckoo
Leghorn Rhode Island Red cross pullets, egg size was
not materially affected by the feeding of extra quantities
of dried skim milk.
When two rations of similar constitution and
mineral analysis, but varying in protein content, were
compared, there was no significant difference in egg
size.
There were no significant differences in egg
size for either pullets or yearling Leghorns when fish
meal replaced meat and bone meal, dried butter milk
replaced dried skim milk, or decorticated earth nut
meal (peanut meal) replaced extracted soya bean meal
in a mixed protein ration.
A mixed protein ration did not give a larger
egg size than a simple protein ration.
There were indications in several of the experiments
that about April or May there is a turning
point in an egg weight cycle.
Further research is required to determine
the relation of the protein and mineral content of the
ration to the size of the eggs produced. It has not
been possible to confirm previous work that proteins
or minerals are of special value in regard to egg
weight.PART II SEX LINKAGE IN THE DOMESTIC FOWL,PART III. A LEG COLOUR CHIMERA. A POSSIBT,F
CASE OF SOMATIC MUTATION IN
THE DOMESTIC FOWL.PART IV. A CASE OF POSSIBLE NON -DISJUNCTION
IN THE DO /0STIC FOWL.PART V. THE INHERITANCE OF THE RE FACTOR
IN THE RABBIT