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oat straw every week. The 100 birds eating the mangolds averaged laying 63.9 eggs each, during the 4 months. The 100 birds eating the clover, averaged 59.6 eggs during the same time. The slight difference between the yields of the two lots can hardly be regarded as indicating greater value for the mangold ration.
The vigor and apparent healthfulness of the two lots were equally good. In the general feeding both mangolds and clover are used daily. Formerly it was thought necessary to steam, or wet the clover with hot water in order to get good results from it. It is now cut and fed dry, in the bottom of cement barrels, cut off about ten inches high. About 5 pounds are eaten daily, by 100 hens, with very little waste. Apparently as good results are gotten from it as when it was scalded; the labor of preparation being very much lessened.
TIME REQUIRED TO ESTABLISH FERTILITY IN THE EGGS OF
HENS WHEN FIRST MATED. Fifty Barrad Plymouth Rock hens, one year old, that had been laying well throughout the preceding winter and spring, and had been kept away from male birds since they were 12 weeks old, were mated with cockerels and their eggs incubated, to determine how soon after introducing male birds into pens of virgin hens, the eggs may be sufficiently fertilized for incubating purposes. Table showing the results of incubating the eggs from 50 hens
during the first 7 days of mating.
Three cockerels were put into the pen at 6 A. M. June 23 and the eggs collected and marked at 9 A. M., 12 M., 3 P. M. and 6 P. M. during that and the days following.
Incubation showed all eggs laid June 23 to be entirely infertile. Three eggs collected at 9 A. M. June 24 showed weak fertility. Four eggs collected at 12 M. of that day showed weak fertility, and two eggs collected at that hour were so strong in fertility that the embryoes in them developed to about the eighteenth day. In a previous test, reported in Bulletin 79 of this Station, two chicks were hatched from the eight eggs laid on the second day of mating.
On June 25th, the third day the birds were mated, they laid 21 eggs and from them 10 chicks were hatched out. The fourth day of mating did not show as good results, the 18 eggs yielding but 4 live chicks. During the fifth day of the mating,
4 the 50 hens laid 31 eggs and they yielded 17 chicks. 'On the sixth day they laid 32 eggs and 16 chicks were hatched out, and on the seventh day the 26 eggs laid, yielded 15 chicks.
These results show that the eggs laid during the days immediately following the fourth day of mating, yielded rather more than 50 per cent of good chicks, which is about the percentage usual in the general incubation work here, which, however, is done earlier in the season, when conditions are supposed to be not as favorable.
HATCHABILITY OF THE EGGS FROM THE SAME HENS DURING
TEN CONSECUTIVE MONTHS. One of the most annoying and perplexing features of poultry work is the large number of eggs incubated, which do not yield chicks. Formerly when the hens lived in warm houses in winter and part of their food consisted of moist mashes, sometimes not more than a fourth of their eggs yielded live chicks. For the last 2 years the average of chicks hatched from the eggs laid by the hens in February and March, has been at the rate of one chick to about 2 eggs, and for those laid during April, less than 2 eggs have been required to yield a chick.
It is hoped that means may be devised by which the present wastes may be reduced, even where chicks are raised in large numbers. In order to study the hatchability of the eggs from the same lot of hens, through their first laying year, a pen of 50 pullets was set apart for the purpose. They were hatched late in May and commenced laying in October, continuing laying moderately, through November and December. The 50 birds were mated in November with 2 cockerels, that did not quarrel, and these matings continued through the 10 months test.
Three of the 50 died and did not do a full years' work, and 7 others laid irregularly and are not considered in the data given below. The hatchability of eggs from the same forty hens each month
from January to October.
During the first 10 days in January, all of the eggs laid by the 40 birds were saved and incubated and the results noted. The same was done through the first 10 days of each succeeding month, ending with October. All of the eggs laid during the several ļo-day periods, were incubated, none were rejected because of lack of size, irregular shape, or defective shells, as would have been done in ordinary selection. This, of course, reduced the percentages of hatchable eggs in all the periods. The results are given in the accompanying table.
The most impressive feature of the table is the per cent of chicks hatched from the July, August and September eggs. The hens had averaged laying 16.6 eggs each, per month, for the 5 months ending with June. July and August were warm months; the egg yields were lessened, and many of the birds were in partial moult, yet the eggs of July yielded 58 chicks per hundred, and those of August, 54 chicks. From this test there appears no support of the theory, that long continued laying reduces the chick-producing capacities of the eggs.
Every egg in the experiment was marked as laid, and its behavior in the incubator noted. Perhaps the data secured from the pen of 40 hens, considered collectively, is as valuable as though the histories of each hen's eggs were traced, individually for the 10 months.
THE EFFECTS OF LONG AND SHORT MATINGS UPON
CHICK-PRODUCING CAPACITIES OF EGGS. As a matter of convenience for many years past our breeding pens have been made up in November. The expense and difficulties of providing roomy pens for the cockerels, separate from the hens, have been the reasons for so doing. It has been easy to see, when the two sexes have been together for several months, that the hens have suffered from the too constant attentions of the cockerels. They have given evidence of this by their somewhat worn condition and loss of feathers from backs and necks, as compared with their sisters, in other pens, where there were no cockerels. The egg yields were no less in the mated, than in the unmated pens, and to appearances the eggs were of as good size in one class as the other.
However that may be, it has been a mater of serious question whether the eggs laid by hens that had been mated so long, with cockerels that had 3 or 4 months' service, were in as good condition for chick yielding as those from freshly mated males and females.
On the first of last November, 15 pens of pullets were set apart for breeding purposes. The birds were hatched between April ist and May 14th, and had not been with cockerels since they were 12 weeks old. Nine of the pens were mated November 25th by putting 6 cockerels into each pen of 100 pullets. They all ran together and mated at will, until February 24th, when the 6 cockerels in each pen were divided into 3 lots, of
2 each. Each lot of 2 cockerels was allowed in turn a half day's freedom, one lot being shut up, and another lot liberated at noon and night, each day. When not at liberty, each 2 cockerels were in coops, 21/2 by 6 feet in size, in company with about half the broody hens of the pen. The coops were light and the birds on the floor were in plain sight of the prisoners at all times.
The other 6 pens of females were kept separate from the males until February 24th, when they were mated with brothers of the cockerels employed in the 9 pens described above. The cockerels and pullets in the 6 pens were fresh, never having been in service. The 6 cockerels assigned to each pen were divided into lots of 2, and each lot given their liberty, alternately, just as they were in the first 9 pens.
The saving of the eggs for incubation was begun March 2, 6 days after regular mating commenced. The eggs were saved from each lot until March 17th, when they were incubated under similar conditions. From the pens where the males and females had run together all winter, 3,240 eggs were incubated and 1,529 chicks hatched out, an average of about one chick from 2% eggs. From the pens where the males and females had not been together until the breeding season commenced on February 24, 2,160 eggs were incubated, and 1,075 chicks hatched out-an average of two eggs being required to yield one chick.
These slight differences in results should not be interpreted as meaning that there are advantages in the short, over the long matings, for so small differences are liable to show in any pens of birds, however treated. Much more marked differences in results would be needed, to indicate that the running together of both sexes, at will, during several months prior to the breeding season, is detrimental to the chick-producing capacities of the eggs.
While the results of this test may not be convincing, the 1,500 birds employed and the large number of eggs incubated, with the satisfactory average yields of a chick from 2 eggs, does furnish data sufficient to remove scruples regarding the fitness of long-mated birds for breeders.