Efecto de progesterona inyectable (p4) aplicada en el día 3 post-inseminación sobre el cuerpo lúteo y la fertilidad en vacas Brahman y Brown Swiss en el trópico ecuatoriano

Abstract

This study evaluated the effect of applying exogenous progesterone on the corpus luteum three days after artificial insemination at fixed time (IATF) in Brahman and Brown Swiss cows, aged 4 to 6 years with condition Body weight between 2.5 and 3 on the scale of 1 to 5. This research was carried out on 29 cows divided into two farms located in the southern tropical zone of Ecuador; In a farm with 15 Brahman cows (n = 5 control group, n = 5 group75 mg, n = 5 group 100 mg) and in another 14 Brown Swiss cows (n = 5 control group, n = 4 group75 mg, n = 5 Group 100 mg). According to the chronogram that was established for this purpose, ultrasound was performed to determine the growth of the corpus luteum (CL) a day over another. It also proceeded to draw blood from the coccygeal vein in all cows for establish the plasma concentration of progesterone (P4) ng / ml. Statistical analysis to determine serum P4 levels and CL morphology was performed using the ANOVA test and to determine the pregnancy diagnosis was performed using the chi-square test, this diagnosis was made with an ultrasound at 60 days after insemination, giving As a result 40% of the Witness group, 44.4% 75 mg and 50% of the 100 mg group. However the treatments evaluated did not present significant differences between them (P > 5), therefore the different doses applied not interfere with development of CL therefore not significantly effect on pregnancy rate