Articles | Volume 69, issue 1
https://doi.org/10.5194/aab-69-101-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/aab-69-101-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
A systematic review and meta-analysis of the effects of inclusion of microalgae in dairy cows' diets on nutrient digestibility, fermentation parameters, blood metabolites, milk production, and fatty acid profiles
Soumaya Boukrouh
CORRESPONDING AUTHOR
African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), Laâyoune 70000, Morocco
Fadoua Karouach
African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), Laâyoune 70000, Morocco
Soufiane El Aayadi
Animal Production Department, Institut Agronomique et Veterinaire Hassan II, Medinat Al Irfane, Rabat, Morocco
Bouchra El Amiri
African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), Laâyoune 70000, Morocco
Animal Production Department, Institut Agronomique et Veterinaire Hassan II, Medinat Al Irfane, Rabat, Morocco
Jean-Luc Hornick
Department of Veterinary Management of Animal Resources, Faculty of Veterinary Medicine, University of Liège, 4000 Liège, Belgium
Abdelaziz Nilahyane
African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), Laâyoune 70000, Morocco
Abdelaziz Hirich
African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), Laâyoune 70000, Morocco
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Short summary
Microalgae have been explored as protein supplements for dairy cows, but results vary. This study assessed their effects using meta-analysis, considering factors like species, inclusion level, and breed. Microalgae reduced dry matter intake but improved fiber digestibility. Milk fat decreased, yet C18:2 c9t11 and C22:6 n-3 increased. Schizochytrium sp. boosted C22:6 n-3, and Holstein–Friesian cows reduced saturated fatty acids, supporting microalgae as a sustainable feed supplement.
Microalgae have been explored as protein supplements for dairy cows, but results vary. This...