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Objective The United States cattle industry suffers substantial monetary losses due to gastrointestinal parasites. There are limited data on extended-release and pour-on anthelmintic treatment on growth and reproductive performance in replacement beef cattle. This study aimed to investigate anthelmintic therapy on postweaning growth performance and reproductive success in fall-born, crossbred replacement heifers. Materials and Methods Eighty-three, newly weaned, Angus crossbred, fall-born heifer calves were stratified by BW at d −14, fecal egg count, and day of age and allocated randomly to 1 of 3 anthelmintic treatments: (1) control, no anthelmintic (n = 28; CON); (2) combination pour-on moxidectin and oxfendazole (n = 28; MO); or (3) extended-release eprinomectin (n = 27; ERE). Heifers grazed within treatment groups on separate pastures for a 274-d period. Respective anthelmintics were administered on d 0 and 154. Body weights, BCS, and calf BW were analyzed using the MIXED procedure of SAS. Heifer cyclicity, estrous detection (using an Estrotect patch), AI conception, natural service conception, overall pregnancy rates, and live calving rates were analyzed using the GENMOD procedure of SAS. Significance was declared at P ≤ 0.05. Results and Discussion Final heifer BW, ADG and BCS were greater (P Implications and Applications The inclusion of an anthelmintic increased growth and improved reproductive performance in fall-born heifers over a 274-d grazing study.

Reducing vortex-induced vibration (VIV) of elastically mounted cylinders has applications to petroleum, nuclear, and civil engineering. One simple method is streamlining the cylinder into an airfoil shape. However, if flow direction changes, an elastic airfoil could experience similar oscillations with even more drag. To better understand a general airfoil's response, three elastically mounted airfoil shapes are tested at a 90° angle of attack in a 3 ft by 4 ft wind tunnel. The shapes are a NACA 0018, a sharp leading- and trailing-edge (sharp–sharp) model, and a round leading- and trailing-edge (round–round) model. Mass-damping ranges from 0.96 to 1.44. For comparison to canonical VIV research, a cylinder is also tested. Since lock-in occurs near Re c = 125 × 10 3 , the models are also tested with a trip strip. The NACA 0018 and sharp–sharp configuration show nearly identical responses. The cylinder and round–round airfoil have responses five to eight times larger. Thus, the existence of a single sharp edge is sufficient to greatly reduce VIV at 90° angle of attack. Whereas the cylinder and round–round maximum response amplitudes are similar, cylinder lock-in occurs over a velocity range three times larger than the round–round. The tripped cylinder and round–round models' response is attenuated by 70% compared to their respective clean configurations. Hysteresis is only observed in the circular cylinder and round–round models. Hotwire data indicates the clean cylinder has a unique vortex pattern compared to the other configurations.