Íslenskar landbúnaðarrannsóknir - 01.09.1977, Page 107

Íslenskar landbúnaðarrannsóknir - 01.09.1977, Page 107
ÖRYGGI í AFKVÆMADÓMI Á NAUTUM 105 Indices for production for individual bulls in each group of herd level have been calc- ulated after which calculations of the corre- lation between the indices were made. These are then compared with expected correlation based on figures for heritability which had previously been evaluated using the same material. For bulls with 30 daughters or more in each group of herd level there is a very good HEIMILDIR — REFERENCES Bereskin, B. og Lush, J. L., 1965: Genetic and environmental factors in dairy sire evaluation. III. Influence of environmental and other ex- taneous correlations among the daughters. J. Dairy Sci., 48: 356—360. Christensen, L. G., 1970: Progeny testing of dairy sires based on field and test-station data. I. Phenotypic and genetic correlations. Acta Agr. Scand., 20: 293—301. Christensen, L. G., 1974: Progeny testing of dairy sires based on field and test-station data. II Half-sib and half-cousin analysis. Acta Agr. Scand., 24: 147—159. Everett, R. W, 1974: An extension approach to new sire summaries. J. Dairy Sci., 57: 972— 976. Ealconer, D. S., 1952: The problem of environ- ment and selection. Amer. Nat., 86: 293—298. Fimland, E., 1973: Vi har ei god grovforku. Bu- skap og avdrátt, 24: 180—181. Fimland, E., Bar-Anan, R. og Harvey, W. R., 1972: Studies on dairy records from Israel- Friesian cattle. II. Estimates of components of variance (covariance) and of parameters related to these components. Acta Agr. Scand., 22: 49 —62. Freeman, A. E., 1967: Genetic aspects of the efficiency of nutrient utilization for milk pro- duction. J. Anim. Sci., 26: 976—983. Gaillard, C., Dommerholt, J., Philipsson, J., Mocquot, J. C., Christensen, L. G., McClintock, A. E., Fimland, E. og Lederer, ]., 1976: First report on the study group on standards in AI agreement between the expected accuracy and the accuracy found in the progeny-testing. As regards the youngest bulls which have their progeny tests based mainly on informa- tion on three year old daughters the accuracy of the progeny-tests was very low. As regards this last item it is argued that the results are biased by the fact that annual production is an inaccurate criterion for the production performance of heifers. bull evaluation. EAAP fundur í Ziirich 23.— 26. ágúst 1976, 34 s. Henderson, C. R., 1973: Sire evaluation and genetic trends. I Proceedings of the Animal breeding and genetics symposium in honour of Dr. Jay L. Lush. ASAS og ADSA, Champaign, Illinois, 10—41. Henderson, C. R., 1974: General flexibility of linear model techniques for sire evaluation. J. Dairy Sci, 57: %3—972. Henderson, C. R, 1975: Use of relationships among sires to increase accuracy of sire evalua- tion. J. Dairy Sci, 58: 1731—1738. Hickman, C. G. og Henderson, C. R, 1955: Components of the relationship between level of production and rate of maturity in dairy cattle. J. Dairy Sci, 38: 883—890. Jónmundsson, Jón Viðar, 1975: Mat á kynbóta- gildi gripanna í nautgriparæktarfélögunum. Freyr, 71: 146—151. Jónmundsson, Jón Viðar, Stefánsson, Olafur E. og Jóhannsson, Erlendur, 1977a: Rannsókn á af- urðatölum úr skýrslum nautgriparæktarfélag- anna. I. Áhrif aldurs og burðartíma. ísl. land- búnaðarr. 9-2, bls. 48—75. Jónmundsson, Jón Viðar, Stefánsson, Olafur E, Jóhannsson, Erlendur, 1977b: Rannsókn á af- urðatölum úr skýrslum nautgriparæktarfélag- anna. II. Arfgengi og fylgni eiginleika. ísl. landbúnaðarr. 9.2, bls. 76—-91. Jónsson, Magnús B, 1976: Kynbótaeinkunnir. Ráðunautafundur 9.—14. febrúar 1976, 18 s. Jónsson, Magnús B. og Jónmundsson, Jón Viðar,
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