[Conclusions on the use of Suisychron in the USSR]. / Istogi primeneniia suisinkhrona v SSSR.

Suisynchron was applied to 2,258 gilts, including 850 from breeding farms. Forty-four pigs were checked to elucidate the influence of sexual maturity on the success of oestrus synchronisation. Suisynchron-Prämix was fed to the animals over 20 days, the daily dose for each pig having been 5 g. Twenty-four hours were allowed to elapse from the last administration before 1,500 I.U. PMSG were injected. Synchronised oestrus occurred in 81.2 per cent of all pigs between four and six days from serum injection. Fertilisation in response to first insemination was recorded from 72.9 percent of the pigs, their fertility rate being 9.7 piglets from each farrowing sow. The results of oestrus synchronisation obtained from fattening pigs were somewhat inferior to those recorded from pigs of breeding units. Suisynchron and serum of pregnant mares can synchronise oestrus in 91 per cent of all mateable sows with no previous cycle. The fertility rates recorded from such pigs did not exceed 59 per cent or were between 28.9 and 31.9 per cent lower than those recordable from pigs with a cycle history prior to the use of Suisynchron.

[Teratogenicity of zinc-metallibur]. / Teratogennost' tsink-metallibura.

Suisynchron-Prämix, 5 g/100 mg active principle, was administered daily to pregnant brood sows over 20 days, beginning from the 15th, 25th, 35th, 45th, and 55th days of pregnancy. The effects of Suisynchron on pregnancy were assessed by slaughter results immediately after administration as well as by farrowing results and slaughter of the newborn piglets. Suisynchron administration between the 15th and 55th day of pregnancy killed the embryos, while teratogenic effects were primarily recorded from administration in more advanced phases, say, between the 45th and 75th days of pregnancy. Teratogenicity was attributable to damage to metabolism which, in turn, had been caused by deviations in the activity of endocrine glands.