Effect of Light Quality on Erratic Egg Laying of Caged Turkey Hens

Abstract

The effect of light quality on erratic oviposition (two eggs laid during a 24-hrperiod) and the shell quality of erratically laid eggs of turkey hens in cages during 20 weeks of production were examined. Hens were exposed to one of the following sources of light: blue, green, red, or incandescant for 16 hr of light per day (16L:8D). The intensity of light was equalized among treatments on the basis of equal number of photons (3.0 X lO'Vcm'/sec).The frequency of erratic oviposition was similar for all light treatments, ranging between 13.4 to 15.3% of total eggs laid, and most occurred in two-egg clutches. With erratic ovipositions, the first egg was laid during the daily dark period, whereas the second egg was laid in the daily light period, 11.6 to 13.0 hr later. Oviposition time and shell quality were significantly influenced by light treatment. As wavelength increased, shell weight of the erratically laid eggs decreased. Thus, shell quality and the timing of oviposition of erratically laid eggs may be influenced by light color. (

Characteristics of oviposition patterns of turkey hens and the influence of different wavelengths of light

“…The hens were then moved into a lightcontrolled house and exposed to 8 h/d of incandescent light. Ten turkey hens were assigned at random at 32 weeks of age to individual wire cages in each of 4 light treatments within the same test room as described previously (Pyrzak and Siopes, 1986). All hens were photostimulated with 16 h/d of light (06.00 to 22.00 h).…”

“…All sources were equalised at a photon output of 3-0 X 10 14 cm 2 /s, measured at the level of the hen's head within the cage. The spectral analysis and intensities have been reported by Pyrzak and Siopes (1986). Food and water were provided ad libitum throughout.…”

“…Unusually short intervals indicating erratic oviposition (Pyrzak and Siopes, 1986) were excluded and thus, by setting the limit to 17 h, about 15% of the total intervals were eliminated. Intervals ranged between 25*7 and 27*6 h with a mean of about 27-0 ±3*3 h. There was no significant effect of sequence length on the mean intervals between successive eggs.…”