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<jats:title>Abstract</jats:title><jats:p>In the postpartum period, there is an increase in non‐esterified fatty acids (NEFA) in both serum and follicular fluid (FF) of cattle. The increase in fatty acid concentration results in increased production of reactive oxygen species (ROS) that can compromise bovine fertility. The objectives of this study were to characterize the lipid profile found in the FF of cows experiencing induced negative energy balance (NEB) and to evaluate the effect of α‐tocopherol in the prevention of oxidative stress in the serum and FF of cows. Twenty‐nine beef cows were divided into groups: (1) control; (2) Fasting for 24 days; and (3) Fasting + VitE. Between D0 and D4 blood samples were taken to assess concentrations of NEFA, ROS production, total antioxidant capacity (FRAP), lipid peroxidation, and α‐tocopherol (vitamin E). On D4, follicular aspiration was performed for analysis of FF from the dominant follicle. Our results demonstrate that fasting was effective in causing increased fat mobilization in animals. The increase in serum concentration of C18:1c9 was reflected in the FF of fasting cows. Serum α‐tocopherol concentration was higher in the control and Fasting + VitE groups compared to the Fasting group. In FF, there was an increase of α‐tocopherol in the Fasting + VitE group in comparison to Fasting cows. There was an increase in ROS production in the serum of fasting cows. ROS production in FF was higher in the Fasting compared to the Fasting + VitE group. Vitamin E has beneficial effects in reducing ROS production in the dominant follicle of cows in NEB.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Sexed semen facilitates additional female calf production for the expansion of a herd at a faster rate and also curtails the surplus production of unwanted male calves. A study was conducted to evaluate the performance of sexed semen in indigenous Tharparkar cows based on 114 artificial inseminations (AI) performed at natural oestrus using two protocols i.e., single AI (<jats:italic>n</jats:italic> = 48) and double AI (<jats:italic>n</jats:italic> = 66). Overall, the first service conception rate (CR) was significantly higher in double (53.0%) than single (33.3%) AI protocol. The odds ratio of conception rate in double AI was 2.26 (<jats:italic>χ</jats:italic><jats:sup>2</jats:sup> = 4.4, <jats:italic>df</jats:italic> = 1, <jats:italic>p</jats:italic> = .04) with respect to single AI. The time that elapsed since the detection of oestrus to insemination was also analysed. In a single AI protocol, the CR was higher (<jats:italic>p</jats:italic> &lt; .05) at 16 h (54.6%) than insemination at 8 h (27.0%) following the onset of oestrus. Yet, the CR using double AI protocol did not differ (<jats:italic>p</jats:italic> = .73) significantly when AIs were performed either at 8 h and 24 h (51.9%) or 16 h and 24 h (57.1%) post onset of oestrus. Besides, like the single AI protocol, the parity of the animals also influenced the CR, being higher in heifers (<jats:italic>n</jats:italic> = 22) than those of parous (<jats:italic>n</jats:italic> = 92) cows (72.73 vs. 40.43%, <jats:italic>χ</jats:italic><jats:sup>2</jats:sup> = 7.48, <jats:italic>df</jats:italic> = 1, <jats:italic>p</jats:italic> = .006) in the present study. The odds ratio of conception in heifers was 3.93 with respect to parous cows. Overall, the birth of female calf was 91.7%. In conclusion, the present study indicates a future promise of the sexed semen for the production of more female offspring from Tharparkar cattle.</jats:p>