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This study, conducted at São Paulo University feedlot, Dracena, Brazil, was designed to evaluate the effect of adding either high-moisture corn, calcium salts of fatty acids (CSFA), or organic Zn+Cr on feedlot performance and carcass traits of Nellore cattle fed for 112 days. One-hundred fifty 18-mo-old Nellore bulls (404±24kg) were used and initially ranked, according to sires' information, into groups of high and low EPD. Secondly, cattle were blocked by weight and randomly allocated to 30 pens (n = 5/pen), which were randomly assigned to the following 2x2 + 1 arrangement of treatments: Finely-ground corn, High-moisture corn, Finely-ground + CSFA, High-moisture corn + CSFA, and High-moisture corn + CSFA + Zn (90 ppm) and Cr (0.45 ppm). All diets contained 25 ppm of monensin. On day 0, one animal per pen was randomly selected to be slaughtered for baseline purposes. The replacement of finely-ground by high-moisture corn increased (P < 0.05) final BW (585 vs. 573 kg), ADG, HCW (321 kg vs. 315 kg) and decreased (P < 0.01) DMI (9.7 vs. 10.1 kg). Likewise, the addition of CSFA increased final BW, ADG (1.62 vs. 1.50 kg), and HCW (321 vs. 314 kg). The addition of Cr+Zn led to increased (P = 0.02) dressing percentage. No treatment effect was observed on final marbling (P > 0.55). It was observed interactions between treatments and EPD for G:F (P = 0.02) and final 12thrib-fat thickness (P = 0.03), where cattle from low-EPD groups needed highmoisture corn, CSFA and organic Zn+Cr to improve G:F and increase fat deposition; however, animals from high-EPD groups required only high-moisture corn. The adding of either high-moisture corn, CSFA, or organic Zn+Cr improved feedlot performance of Nellore cattle, and its effects seemed to be more effective in animals from low-EPD groups. [ABSTRACT FROM AUTHOR]

• Crossbred dairy cows were supplemented strategically with CSFA for 30 days in AIFT programs. • The functionality of the ovarian structures was evaluated through doppler ultrasonography and hormonal dosing. • The strategic supplementation with CSFA 30 days before de AIFT did not improve follicular and luteal morphofunctionality. • Further studies need to be performed to evaluate the best time to start supplementation and the duration of this strategy. We aimed to define the effect of strategic supplementation with calcium salts of fatty acids on the morphofunctionality of ovarian structures in crossbred dairy cows submitted to a hormonal protocol for artificial insemination at a fixed time (AIFT) A total of 20 lactating crossbred females (Bos taurus x Bos taurus indicus) were randomly divided into two groups, the control group (CON), which received concentrate with no added fat in the diet, and the treatment group (TRAT), which received concentrate with salts of fatty acid calcium (Megalac-E, Church and Dwight Co. Inc., Trenton, NJ, marketed in Brazil by Elanco-Eli Lilly and Company, Indianapolis, IN, USA). The diets were provided for 30 days. The animals started consuming the supplement 20 days before the beginning of the follicular wave and ovulation synchronization protocol (Day-20). Follicular development was monitored by mode B ultrasound and power-doppler assessments every 12 h between day D8 and the time of ovulation. By measuring the follicular diameter (DFOL), the area of the follicular wall (AFOL) and the vascularization area of the follicle wall (VFOL) were able to be determined. On days 7 and 16 after ovulation, US mode B and doppler were performed in order to analyze the corpus luteum diameter (DCL), area of the corpus luteum (ACL), and the vascularization area of the corpus luteum (VCL). In addition, blood samples were collected to measure the serum concentration of P4 using chemiluminescence methodology. There was no effect of supplementation on milk production results (p = 0.15), body weight (p = 0.57), ECC (p = 0.78), albumin (p = 0.83), and the lipid profile (CT [ p = 0.36], HDL [ p = 0.11], LDL [ p = 0.55], VLDL [ p = 0.15] and TRIG [ p = 0.15]). The supplementation of SCAG, 30 days before IATF, under the conditions of this experiment had no significant influence on follicular and luteal morphofunctionality. However, suspension of supplementation caused a deficit in the luteal blood flow. [ABSTRACT FROM AUTHOR]