Date of Award


Degree Name

MS in Agriculture - Animal Science


Animal Science


College of Agriculture, Food, and Environmental Sciences


Darin Bennett

Advisor Department

Animal Science

Advisor College

College of Agriculture, Food, and Environmental Sciences


Research has shown Spirulina to be a viable feedstuff in poultry production. Other species of microalgae are being studied to determine their effects on poultry production. This project compared four microalgaes: Hydrodictyon, Vaucheria, Uronema, and Spirulina and was broken down into three trials. The first experiment investigated the digestibility of an algae species, Spirulina, in broiler chicken diets. Eighty, 25-day-old Ross 708 broiler chicks were sorted into 20 metabolism cages and received one of two diets: Control Diet or Test Diet (75% basal diet + 25% Spirulina). The apparent ileal amino acid digestibility (AIAAD) of lysine, methionine, cysteine, threonine, isoleucine, valine and arginine in Spirulina was 94.5%, 91.3%, 56.1%, 71.4%, 76.8%, 69.8% and 90.4% respectively. Apparent metabolizable energy (AME) of Spirulina was 2279 kcal/kg. The second experiment focused on digestibility of Spirulina and novel algae species in laying hens. Sixty, 80-week-old Lohman LSL-Lite laying hens were randomly assigned to Control Diet, Hydrodictyon Test Diet (87.5% basal diet + 12.5% hydrodictyon), 12.5% or one of three other test diets (75% basal diet + 25% Spirulina, Uronema, and Vaucheria). Spirulina diets contained the highest crude protein (25.5%) and methionine levels (0.68%). Uronema had the highest gross energy content of 3880.5 kcal/kg and lysine levels (1.12%). Hydrodictyon diet was the most nutritionally similar to the control. Crude protein was at 15.3% and 16.6% for control and Hydrodictyon respectively. Gross energy was 3429.6 kcal/g in control versus 3316.1 kcal/kg in Hydrodictyon. Lastly, crude fat was 2.7% compared to Hydrodictyon at 2.4%.

The last trial was to determine the effects of the addition of microalgae in the diet on laying hen production. Seventy-eight, 23-month-old laying hens were assigned to 1 of 3 of the following experimental diets: control, control + 1% microalgae, or control + 2% microalgae. Microalgae, regardless of inclusion level, had no significant effect on egg weight in this study. Increasing level of inclusion of Spirulina, Hydrodictyon, and Uronema from 0 to 2 % significantly increased yolk color. Vaucheria influenced yolk color at the 2% level. No significance differences shown from any of the algae species regardless of inclusion level for egg weight, egg mass, shell thickness, shell strength, shell weight, albumen weight, yolk weight, and albumen height. In addition, there was no significant difference in feed conversion ratio, feed intake, body weight, or tibial strength between the treatments. However, as these are novel algaes, further studies are required to determine the true usability in poultry production.