Performance of the hybrids of the white- and brown-egg layer type in Czechoslovakia and FRG
1991
Hyankova, L. (Vyzkumny Ustav Zivocisne Vyroby, Prague-Uhrineves (CSFR)) | Tlaskal, J.
The white-egg White Hisex and Shaver Starcross 288 hybrids and the brown-egg Tetra SL hybrid, kept at one testing station in Czechoslovakia (Ivanka pri Dunaji) and at three testing stations in the FRG (St. Johann, Kitzingen, Neu Ulrichstein), were compared for their performance during the period from the 1981/1982 season to the 1985/1986 season. In both types of layers, a much lower performance was recorded at Ivanka pri Dunaji. The decrease of performance under Czechoslovak conditions, i. e. reduction of body weight and egg yield and increase in mortality and feed consumption per 1 kg of egg matter, is not the same in all the final hybrids. Layers of the White Hisex hybrid exhibit the most sensitive response to worse environmental conditions. Their greater mortality during the production programme allows the Tetra SL layers to produce more egg matter and to have a higher egg yields converted to the starting stock of the birds, although in the FRG the white-egg hybrids always have higher egg yields than the Tetra SL hybrid layers. Expressing the total performance on the basis of the profit function, it is clearly seen - taking into account the current prices in Czechoslovakia - that the layers of the Tetra SL hybrid are better.
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