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The objective of this study was to compare nutritional and management strategies on performance of beef calves at weaning. Forty crossbred beef calves were assigned to receive either nutritional supplementation (Drench) 3 wks prior to weaning and again at weaning or nothing (Cntrl). In addition, calves were assigned 1 of 3 weaning treatments: 1) abrupt weaning with complete separation (Abrupt); 2) 4d fence line weaning with cows allowed to interact with calves through a fence for 4 d before removal (4Fence); and 3) 7 d fence line weaning with cows allowed to interact with calves through a fence for 7 d before removal (7Fence). Calves were blocked by sex and BW. Nutritional supplementation consisted of an oral drench (5cc/100 lbs. BW; Cellarator Turbo Drench; ADM Animal Nutrition; Quincy, IL). Calves were weighed at weaning, 7 d after, and 85 d after weaning. At weaning, average age of calves was 213 ± 19 d and average weight 224 ± 30 kg. Average final weight of calves was 279 ± 33 kg. Weight differences between weaning and 7 d after weaning and weaning and 85 d after weaning were analyzed using Proc Mixed with nutritional supplementation, sex, and weaning duration as fixed variables. Calves receiving Drench gained more (P < 0.05) 1 wk after weaning (7.9 vs. 3.7 kg, respectively). Weight gains 85 d after weaning were not different (P > 0.05) 7 d after weaning. Weight gain in calves assigned to 4Fence and 7Fence treatments were not different (P < 0.05) but gained more (P < 0.05) than Abrupt calves (8.5 vs. 7.6 vs. 1.2 kg, respectively). Weight gains 85 d after weaning were not different (P > 0.05) between weaning treatments. In conclusion, nutritional supplementation and fence-line weaning improved calf performance 1 wk after weaning but not after 3 mo.

Introduction of antioxidants, such as quercetin, into the diets of livestock species have become a new and revolutionary field of study. The objective was to examine effects of dietary supplementation of quercetin in beef heifers. Assessments were evaluated based on uterine artery hemodynamics and maternal hormone concentrations during late-gestation, as well as calf morphometric parameters. Eleven pregnant, Angus x Brahman heifers were randomly assigned to receive one of two dietary treatments: 1) quercetin (250 mg/day; Liftmode.com, Synaptent LLC, Chicago, IL, USA) supplemented group (QR; n = 6) or 2) no quercetin supplemented group (CON; n = 5). Dietary treatments were applied daily from d 190 of gestation until calving in a Calan System (American Calan, Inc., Northwood, NH) with 3.63 kg of a commodity grain and approximately 8.16 kg of hay per head per day. Both groups were subject to ultrasound scanning via rectal ultrasonography of the uterine artery using Color Doppler on d 190, 220, 250, and 270 of gestation. Blood samples were also collected via coccygeal venipuncture for hormone analysis. Data were analyzed using the ANOVA method within the Proc Mixed procedure of SAS 9.4. Total blood flow was greater (P < 0.05) on d 248 and even greater (P < 0.05) on d 270 of gestation as compared to d 190 and 220. Contralateral Pulsatility Index (PI) was greater (P < 0.05) in QR treated heifers as compared to CON. Additionally, QR heifers yielded a greater serum progesterone concentration (P < 0.05) as compared to CON but no differences (P > 0.05) between treatments regarding serum estrogen concentrations. Calf birth weight was not different (P > 0.05), but calves from quercetin supplemented dams resulted in greater wither and hip height (P < 0.05). Future research with antioxidant supplementation could lead to further fetal programming implications.