Wpływ sztucznego skrócenia dnia świetlnego na przyrost masy ciała, pokrój i jakość skór lisów polarnych

The studies were caried on in two consecutive years /1987 and 1988/. The cages of foxes from experimental group were blacked out by tarpaulin for two month/1st August - 30 September/. The animals from every litter were allocated to control and experimental group considering sex. The light’s tension in experimental pavilion not passed 26 - 32% in cloudy day and 40-48% in sunny day of value light's tension in control pavillion. The artificial abbreviation of daylight corrected category of coat, class and value of furs, as well as their furriery qualities /less weight of hide, less thickness of cover hair and increasing of underfur hair's height/. The blackout of cages advanced mature coat of foxes. In result the period of foxe's feeding was abbreviated about 12,4 - 15.9 days, food was spered and cost of work was less. The profil constituted 30% of fur's value in 1987 year and 17% - in 1988 year.