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 - 2026
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
Boukrouh, Soumaya; Karouach, Fadoua; El Aayadi, Soufianeet al.
2026 • In Archiv für Tierzucht, 69 (1), p. 101 - 115
Genetics; Agronomy and Crop Science; Plant Science
Abstract :
[en] Recently, microalgae have been used as protein supplements to improve the productivity of dairy cows. However, the results are inconsistent among different studies. Thus, the aim of this study was to assess the effects of dietary microalgae incorporation on animal performance. The effect of microalgae was assessed by examining the raw mean differences (RMDs) between the treatment (with microalgae) and control (without microalgae) diets using a random-effect model. Heterogeneity was evaluated through meta-regression and subgroup analyses using microalgae species, inclusion level, days in milk, experimental duration, and cow breed as covariates. Microalgae supplementation decreased the intake of dry matter (DM), organic matter, and neutral detergent fiber (NDF). NDF digestibility improved, whereas the acetate:propionate ratio decreased. Milk and lactose yields remained unchanged. Despite a decrease in milk fat, the fatty acid (FA) profile improved, especially considering the increase in conjugated linoleic acid (CLA) C18:2 c9t11, docosahexaenoic acid (DHA) C22:6 n-3, and mono- and polyunsaturated FA (MUFA and PUFA) and the decrease in the n-6:n-3 ratio. The main sources of variation in the responses to microalgal inclusion in cow milk production and quality were the animal breed, microalgae species, and their level of incorporation. In general, the incorporation of 61-100 g kg DM-1 of microalgae improved milk beneficial FA, including eicosapentaenoic acid (EPA) C20:5 n-3 and DHA, and Schizochytrium sp. increased DHA levels. The Holstein and Friesian breeds were characterized by a significant decrease in saturated FA (SFA). As a result, microalgae supplementation could be a sustainable agricultural practice for improving dairy cow milk quality.
Disciplines :
Animal production & animal husbandry
Author, co-author :
Boukrouh, Soumaya ; Université de Liège - ULiège > Fundamental and Applied Research for Animals and Health (FARAH) ; African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), Laâyoune, Morocco
Karouach, Fadoua; African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), Laâyoune, Morocco
El Aayadi, Soufiane ; Animal Production Department, Institut Agronomique et Veterinaire Hassan II, Rabat, Morocco
El Amiri, Bouchra; African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), Laâyoune, Morocco ; Animal Production Department, Institut Agronomique et Veterinaire Hassan II, Rabat, Morocco
Hornick, Jean-Luc ; Université de Liège - ULiège > Département de gestion vétérinaire des Ressources Animales (DRA)
Nilahyane, Abdelaziz; African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), Laâyoune, Morocco
Hirich, Abdelaziz; African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), Laâyoune, Morocco
Language :
English
Title :
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
We acknowledge the African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P), for financing this study. This research has been supported by the African Sustainable Agriculture Research Institute (ASARI), Mohammed VI Polytechnic University (UM6P).
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