Effect of Practical Diets with Animal or Vegetable Protein Sources and Poultry Oil or Menhaden Fish Oil on Adult Fathead Minnow in Tanks

Abstract

The fathead minnow Pimephales promelas is one of the main species cultured in ponds in the southern United States for bait and is widely used as a toxicological and biomedical model in the laboratory. Diet can have a major impact on performance criteria, both in laboratory and production settings. However, the nutrient requirements of fathead minnow are unknown and cannot be used to formulate optimal diets. To facilitate applied nutrition research for this species, we measured the growth, survival, feed conversion, and response to low dissolved oxygen exhibited by adults that were held in tanks and fed practical diets with animal (menhaden Brevoortia spp. fish meal and poultry by-product meal) or plant (mostly soybean) protein sources and either poultry oil or menhaden fish oil for 12 weeks. Good weight gain (0.6–0.8 g) was obtained either with vegetable or animal protein sources. Poultry oil enhanced growth relative to menhaden fish oil in diets with either vegetable or animal protein sources. Mean survival rates of fish fed the animal and vegetable protein diets were 88% and 96%, respectively, and survival was not affected by lipid source. Survival during the low-oxygen stress test was high (≥90%) across diets, and there were no treatment effects. Vegetable proteins and poultry oil are promising alternatives to more costly feed ingredients in practical diets for fathead minnow.

Notes

¹ In this nomenclature, the number to the left of the colon is the number of carbon atoms, the number immediately to the right of the colon is the number of double bonds, and the number after the hyphen indicates the position of the first double bond from the methyl end.