NR AWPO
AU van Kaam,J.B.C.H.M.; Finocchiaro,R.; Vitale,M.; Vitale,F.; Caracappa,S.; Portolano,B.
TI Risk assessment of selection for resistant PrP alleles on milk production in Valle del Belice
QU International Conference - Prion 2006: Strategies, advances and trends towards protection of society - 3.10.-6.10.2006, Torino, Italy, Lingotto Conference Centre - Poster sessions RA-15
PT Konferenz-Poster
AB To avoid any risk of scrapie or BSE in sheep to humans the EU decided that selection against susceptible PrP alleles should be implemented. This means that all susceptible PrP alleles should be eradicated from the EU sheep population. Such a selection can adversely affect any traits which are directly or by linkage associated with PrP genotypes. A study has been undertaken to determine if PrP genotypes or individual PrP codons have an effect on milk production traits. A total of 501 Valle del Belice sheep with both production as well as PrP genotype information was available. In total these ewes had information on 5472 test-days from 796 lactations. The analysed traits were: Milk yield, Fat yield, Protein yield, Fat+Protein yield, % Fat, % Protein and Somatic Cell Score (SCS). A variety of mixed models were used for the analyses accounting for additive, dominance and epistasis effects of up-to three PrP codons. An effect of the PrP gene in Valle del Belice dairy ewes on milk, fat and protein yields appears significant. No significant effect on fat and protein percentages and on somatic cell score was found. Given the strong influence of a single animal, the only one with the AHQ/AHQ genotype, the significances are doubtful; without this animal only milk yield remained significant. Selection to obtain homozygous ARR/ARR animals is expected not to result in any production changes, because the ARR/ARR animals were producing on the population average.
AD J.B.C.H.M. van Kaam, M. Vitale, F. Vitale, S. Caracappa: Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri", Palermo, Italy R. Finocchiaro, B. Portolano: Dipartimento S.En.Fi.Mi.Zo., Sez. Produzione Animali, Università degli Studi di Palermo, Palermo, Italy. Email: jtkaam@unipa.it
SP englisch
PO Italien