Effect of synthetic prostaglandin F2α analogue (cloprostenol) on litter size and weight in a rabbit line selected by growth rate

Abstract

The effect of a treatment with a synthetic analogue of prostaglandin F_2α (cloprostenol) administrated intramuscularly on day 28 of pregnancy in does belonging to a synthelic rabbit line selected by growth rate (line R) was studied. A reduction in gestation length was observed after treatrnent with prostaglandins (31.3±0.1 vs 32.4±0.1 days, for treated and control groups, respectively, P<0.05). Litter size al birth, and live-born pups were not affected by the treatment. Individual weight of young rabbits al birth was significantly different between treatrnent groups (52±1 vs 58±1 g, in treatment and control group respectively, P<0.05). In the control group, young rabbils born from multiparous does were heavier than those from pnmIparous (53±2 vs 63±1 g, in primiparous and multiparous does respectively, P<0.05). There were not differences in birth weight of kils from treated multiparous and primiparous does. At weaning, individual weight was not affected by treatrnent (578±12 and 561±10 g, in control and treatment group respectively), and differences were observed in reproduclive status (513±12 vs 626±9 g, in primiparous and multiparous does respeclively, P<0.05). An increase in mortality was observed during lactation period afler treatrnent with PGF_2α (48% vs 26%, in cloprostenol and control group respectively, P<0.01).