- Animals: bovine
- Animal Production: animal protection and health, livestock breeding
The purpose of the proposed project is to evaluate the effects of injectable trace mineral supplements administered 30 days before the start of the breeding season on pregnancy rates, distribution of calf birth, and weaning weights in beef herds bred via natural service (i.e. breeding bulls). A group of producers and Extension agents have defined reproductive performance as a critical component of profitability, has been involved with planning efforts, and looks forward to conducting and evaluating the following experiment: Within each of six commercial beef operations, cows will be assigned to one of two treatments: 1) cows will be administered sterile saline subcutaneously on d -30 relative to bull turn out (CON; n = 500); or 2) cows will be administered an injectable trace mineral supplement (60, 10, and 15 mg/mL of zinc, manganese, and copper, as disodium EDTA chelates, and 5 mg/mL of selenium as sodium selenite) subcutaneously on d -30 relative to bull turn out (TM; n = 500). Baseline mineral status will be determined within each herd at the time of treatment administration by evaluating mineral content of blood and hair samples from a subset of cows, as well as samples of water and forage. Key response variables evaluated (which are directly related to producer profitability) include: pregnancy rate at the end of the breeding season, distribution of calf birth throughout the calving season, and weaning weights for the year of administration as well as the year following administration. Outcomes of the project will document the effect of an injectable trace mineral supplement of pregnancy rates, distribution of the calving season, and potential growth of offspring when dams are administered a mineral supplement. Outcomes will also document the change in knowledge for the cooperating producers and extension personnel in the areas of mineral supplementation and management practices, change in management techniques, and quality of life of cooperating producers. Outcomes will be used to determine the impact of trace mineral administration on producer profitability, sustainability of ranch/farm, and quality of life of cooperating producers.
Project objectives from proposal:
Commercial producer interaction and on-farm research will be the focus of the proposed project. Extension agents in the state of North Dakota have identified 6 commercial producers interested in conducting the proposed experiment. Selection of producers was based on a history of good record keeping and commitment to all phases of the proposed research. Producers willing to assist with this effort have been involved from the inception of the experiment, including planning, and will be involved in conducting and evaluating research. Producers will assist personnel with data collection and record keeping for their operation.