OBJECTIVE To assess the repeatability and accuracy of polymer replicas of small, medium, and large long bones of small animals fabricated by use of 2 low-end and 2 high-end 3-D printers. SAMPLE Polymer replicas of a cat femur, dog radius, and dog tibia were fabricated in triplicate by use of each of four 3-D printing methods. PROCEDURES 3-D renderings of the 3 bones reconstructed from CT images were prepared, and length, width of the proximal aspect, and width of the distal aspect of each CT image were measured in triplicate. Polymer replicas were fabricated by use of a high-end system that relied on jetting of curable liquid photopolymer, a high-end system that relied on polymer extrusion, a triple-nozzle polymer extrusion low-end system, and a dual-nozzle polymer extrusion low-end system. Polymer replicas were scanned by use of a laser-based coordinate measurement machine. Length, width of the proximal aspect, and width of the distal aspect of the scans of replicas were measured and compared with measurements for the 3-D renderings. RESULTS 129 measurements were collected for 34 replicas (fabrication of 1 large long-bone replica was unsuccessful on each of the 2 low-end printers). Replicas were highly repeatable for all 3-D printers. The 3-D printers overestimated dimensions of large replicas by approximately 1%. CONCLUSIONS AND CLINICAL RELEVANCE Low-end and high-end 3-D printers fabricated CT-derived replicas of bones of small animals with high repeatability. Replicas were slightly larger than the original bones.

The present study aimed to evaluate the economic feasibility of production and commercialization project of Hay Enriched Extruded (HEE) as a complete diet for horses. The study was based on survey data and quotation activities involving price from the land preparation (repair, planting and fertilization) to the processing of the product at the factory (extrusion) and marketing. Transportation costs and taxes were also considered. Discounted Cash Flow (30 years) was used to calculate the profitability indicator and the Profit and Loss Statement (PLS). Calculations were developed using Microsoft Office Excel® spreadsheets. Three production scenarios were simulated with different consumer prices: Scenario 1 - equivalent to the complete diet, where the ingredients are supplied together, but purchased separately; Scenario 2 - Considering a value 10% higher than the complete diet; Scenario 3 - Considering a value 20% higher than the complete diet. We observed that the project was economically viable in the three suggested scenarios with positive Net Present Value, Internal Rate of Return greater than 9.4% and payback of 11 to 2 years. The results enable us to conclude that the product may be a promising investment for both product quality and ease of use as the rapid return on invested capital.