Effects of vitamin B1, vitamin E and selenium on pregnancy and blood metabolites profile during non-breeding season and early prediction of pregnancy by thermographic monitoring in Merino ewes

Abstract

The objective of this study was to evaluate the effects of injectable selenium, vitamin E and vitamin B1 compounds on serum metabolic profile and pregnancy rates (PR) during the non-breeding season in Merino ewes that were synchronized with progesterone and equine chorionic gonadotrophin (eCG). Thermographic monitoring of ewes on the last day of synchronization was successful in the early selection of ewes to be used in artificial insemination and its relationship with pregnancy outcomes. Cyclic and non-pregnant ewes (n=75) were randomly assigned to treatment (n=30) and control (n=45) groups. All animals were synchronized using PGF2α at day 0, progesterone impregnated intravaginal sponges for 14 days, eCG 48 h before sponge withdrawal and artificial insemination were carried out 43–45 h after sponge removal. Animals of treatment group (n=30) were administered (intramuscularly) with 1 mg sodium selenite, 60 mg vitamin E and 40 mg vitamin B1 on two occasions, at the beginning of sponge insertion and following sponge removal. Blood samples were collected at sponge insertion and removal. Perianal and perivulvar areas were considered to evaluate the thermal pattern at day 0 and 14 using a thermo camera. Overall, 90.6% of ewes exhibited estrus in response to the synchronization protocol. Ewes of treatment group showed greater PR as compared to that of control group (70.3% vs 56%). Perivulvar temperature was influenced by time only. At the time of sponge removal, perivulvar temperatures were significantly lower in pregnant ewes than in non-pregnant animals. In conclusion, injectable selenium, vitamin E and vitamin B1 compounds increased PR after synchronization protocol and thermographic evaluation that was performed on the last day of synchronization could be used for very early prediction of pregnancy.