tailieunhanh - báo cáo khoa học: "Reaction to halothane anaesthesia among heterozygotes at the halothane locus in British Landrace pigs"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Reaction to halothane anaesthesia among heterozygotes at the halothane locus in British Landrace pigs | Génét. Sél. Evol. 1988 20 3 357-366 Reaction to halothane anaesthesia among heterozygotes at the halothane locus in British Landrace pigs . SOUTHWOOD . SIMPSON and . WEBB AgricuZmraZ and Food Research Council Institute of Animal Physiology and Genetics Research Edinburgh Research Station West Mains Road Edinburgh EH9 3JQ United Kingdom Summary The probability of heterozygotes at the halothane locus reacting to halothane anaesthesia was investigated using five generations of British Landrace pigs selected for positive or negative reaction to halothane. Various models of inheritance of the halothane reaction were tested using maximum likelihood. In general within the selection lines a recessive model in which no heterozygotes react adequately described the data. The positive and negative selection lines were crossed at generations 3 4 and 5 and an average proportion of of offspring from matings between the lines reacted to halothane. However after allowing for the presence of heterozygous parents in the negative line the probability of a heterozygous offspring reacting was estimated to be less than . The incidence of halothane reaction was higher in offspring born out of positive than out of negative dams V p when crossed to negative and positive sires respectively. This difference could not be completely explained by heterozygosity in the negative selection line suggesting some form of maternal effect on the probability of a heterozygote reacting. The genetic nature of this effect was examined by backcrossing putative heterozygous females to halothane positive and negative males. The backcross suggested that the maternal effect was due to maternal environment rather than cytoplasmic inheritance. Key words halothane reaction inheritance heterozygotes maternal effects British Landrace pigs. Resume Sensibilité à I halothane chez des pores de race Landrace britannique heterozygotes au locus halothane La probabilité qu un animal .