Abstract

In order to struggle against perinatal lamb mortalities, one hundred and twenty of Algerian Rumbi ewes were used in our study. These ewes belong to a private farm located in the region of Tiaret; our work was based on the programming of three reproduction seasons over a period of two years (September 2004 to September 2006). During each season, our sheep have received treatment of oestrous synchronization, control and qualified assistance of lambing. These techniques have clearly improved performances of our ewes with respective average rates of fertility, fecundity and prolificacy of 96.38, 135.83 and 140.92% and most of ewes those received Dexamethasone on day 144 of pregnancy lambed within 72 h with a mean interval from treatment to lambing of 52.61 ± 6.32 h. We also reduced the total rate of lamb losses to 7.77% and made it possible to obtain an average of 3.75 lambs by ewe in two years.

Key words: Control of breeding, lambs, mortality, qualified assistance.