Prabhakaran, VSelvaraju, MEzakial Napolean, R; et al.TANUVAS2020-03-032020-03-032019-12http://krishikosh.egranth.ac.in/handle/1/5810144104TNV_35thVCRI_CA_Dec-2019_IFBO-29Repeat breeder cows between second and fifth parity were selected and they were randomly and equally divided into five groups as Group I, II, III, IV and V, each group consisted of 20 cows. Out of 128 repeat breeding cows, 100 cows (78.13 per cent) were selected for the study based on the white side test and it indicated 21.87 per cent repeat breeding cows were affected with subclinical uterine infections. There were 100 and 90 per cent oestrus responses in group IV and V, respectively. There was no significant difference in the mean duration of oestrus among groups II, III and IV. However, these 3 groups significantly (P≤0.05) differed from group I and V. The difference in mean duration of oestrus between group I and V was statistically significant (P≤0.05). The highest percentage (75 per cent) of cows in group II exhibited intense oestrus intensity followed by group IV in which 60 per cent cows showed the same. Pregnant and non-pregnant cows of all the groups had a gradual increase in the diameter of CL from day 5 to 60 and day 5 to 15, respectively. There was a drastic reduction in the diameter of the CL on day 20 in the non-pregnant cows of all the groups.The mean diameter of CL in non-pregnant cows was lower than pregnant cows in different days in all the treatment and control groups. From day 5 to 60, diameter of the CL was higher in group II pregnant cows than the other groups. In group I, II, III, IV and V, the percentages of conception rate were 40, 75, 55, 60 and 50, respectively. When compared to control (40.00 per cent), all the experimental groups exhibited high rate of conception with the highest conception rate in group II (75.00) followed group IV (60.00), III (55.00) and V (50.00 per cent). Hence, it is concluded that administration of antioxidants along with mineral mixture improved the conception rate in repeat breeder cows.enVeterinary ScienceOther