Quantification of cytokines in the amniotic fluid at the moment of delivery of Nelore calves conceived by in-vitro production and artificial insemination

The aim of the present study was to compare the concentrations of cytokines in the conceptus’ amniotic fluid at the moment of delivery of Nelore calves conceived from embryos produced by in-vitro (IVP) or after artificial insemination (AI). Forty cows were divided into 2 groups: 1- 20 cross-bred Nelore cows pregnant with Nelore calves derived from IVP embryos produced from oocitum pick up (OPU) oocytes; 2 - 20 pregnant Nelore cows bearing AI Nelore calves. The animals were fed pasture and had a free access to mineral salt and water. Around labor, cows were transferred to a maternal paddock permitting delivery observation. During the expulsion phase of the delivery, the amnion was punctured by 40x12g needle and a 20 mL syringe and the fluid was collected into a sterile plastic tube and stored in a freezer at -20C. TNF-? and IFN-? concentrations were measured by immunoenzymatic assay using a commercial kit according the manufacturer´s recommendations. Mann-Whitney’s U-test was used for statistical analysis with a significance of 5%. The median of TNF-? level in the amniotic fluid was significantly higher in group 1 (398.7pg/mL) than in group 2 (151.2pg/mL). Furthermore, the median for IFN was not significantly different between the groups. In conclusion, the TNF-? were detectable in the all samples and same in the human species it accomplices of the normal delivery mechanism in ideal concentration and all animals had a similar INF-? pattern, which did not lead to the synergism with TNF-? as reported in other studies.