STANDARD EGG SIZE

Wanganui Chronicle, Volume 80, Issue 103, 4 May 1938, Page 11

STANDARD EGG SIZE

From the economic point of view, and with the object of maintaining a breed at a high commercial standard, the size of egg is of major importance. The necessity for a two-ounce egg for incubation is well recognised, but not sufficiently or rigorously en-’ forced among those with a desire to produce large numbers of chickens early in the season, writes Mr. V. 11 Brann, poultry instructor. Layers of small eggs aie mostly pullets, upon which the farmer is largely dependent for production of earlyhatched stock, and these pullets must themselves have been hatched early during the previous season to be old enough to make suitable breeding stock. It has frequently been stresses. that a 10-months-old pullet whic.i: docs not lay a first-grade egg will i never be a suitable breeder, he con- i tinues. Several farmers are careful to re- ■ ject small eggs for incubation, but the ■ actual layers of small eggs are not i identified. The following season, au second-season hens, they are from ah ! outward appearances suitable specimens for breeding from and in mo # ; instances will then be laying a lirstgrade egg; chickens are bred from J them and so no material improvement:

is made in egg size, he declares. Observation has shown that theiei is considerable variation in the sizes I of eggs laid by individual birds, anti the only satisfactory method to check egg size is to install trap nests, so that a record of the eggs and weights can be kept for all stock. Rejected birds could be identified by rings, so that there would be no chance of their being used Jis breeding stock. To follow this system, it would be necessary to mate as early as possible, preferably by the middle of April, to have the pens complete in readiness to start hatching early in June. Management of the Battery The first tests with caged layers at the Ohio Agricultural Experimental Station were begun in the autumn of 1924. It was then that information first became available as to how the ration could be supplemented to vita-! min D to enable chickens to live in- j doors or in cages without exposure to i direct sunlight. The information was j so new that it was considered doubt--ful if the pullets could live througa I the winter in cages; hence 16 inferior! single-comb White Leghorn pullets were selected as supposed martyrs foi Lhc test. Contrary to expectations, none tn the original 16 inferior pullets died during the first year. After these promising results, half of the original 16 pullets were replaced by better grade pullets. Of the remaining eight original pullets, the first died during the second year, none the third year, and at the end of the fourth year the second pullet died. This was 25 per cent, mortality in four years. Of the eight better-grade pullets, one died of bumblefoot the first year, none during the second and third years, and the second pullet died towards the end of the fourth year. Again there was 25 per cent, mortality during the first four years, as in the case of the original eight pullets started the year before. Egg production was a surprise. The first eight inferior pullets average 112 eggs a bird the first year, and a total of 262 eggs a bird during the first three years; whereas the egg production of the better grade pullets placed in cages a year later was 144 and 335, respectively. One of the original pullets lived in the original cage seven years (lacking three weeks) and laid 544 eggs. 95 of which were laid during the seventh year. It might seem that after almost 14 years of continuous tests at the Ohio Agricultural Experimental Station, the question of layers in batteries shouici be answered. Of particular interest at the moment are the station’s four-ycar continuous tests with pullet layers in batteries against similar pullets confined to indoor floor pens. Five different management procedures were employed in raising the chicks and growing pullets which represented the layers used in the tests, fresh range, used range after two weeks, used range after eight to lu weeds, wire sun porch, and batteries. The total number of tests was 20,! the average yearly length of the tests; 48 weeks, and the total number of pullets involved, 1400. The layers in batteries and floor pens received the same coarse, allmash feed mixture twice daily in about the amount that would be consumed between feeding periods. In other tests this ration and method of feeding proved as effective as whole grain and mash rations. Although the four years’ results present a rather favourable showing lor the layers in batteries, a more fair comparison necessitates the omission of the results of the year 1934-35, during which the layers in batteries suffered from a deficiency of vitamin D, whereas the birds exposed more oi Jess to direct sunlight in floor pens did not. The vitamin D deficiency lowered egg production and increased the rate of mortality before it was discovered and corrected. The cod-liver oil used at the time was found to be below the rated potency for vitamin D. This demonstrated that one must be continually on guard against a possible vitamin L ; deficiency in battery rations. But it may be the only special requiremeni of layers in batteries from that of layers on indoor floor pens with sun pai- ■ lours. If the one year’s tests in which the battery layers suffered from a vitamin D deficiency are omitted, the I average results of the other three t years’ tests become more favourable c to the layers in batteries as compar- ( ed with those in floor pens. p Summing up the results of the four f years’ tests, there was no difference j in egg production, but there was con- ( sistently better live-ability of the lay- s ! ers in batteries. j