Meta-analysis of Arthrospira platensis on growth traits, blood characteristics and antioxidative status of small ruminants

Abstract Arthrospira platensis (AP) has gained increasing attention in the last two decades in ruminant nutrition for its several nutritional and pharmacological benefits. However, the influence of dietary AP intervention on small ruminant performance and health is not well understood. Therefore, this meta-analysis tested the effect of dietary AP on growth characteristics, blood, and antioxidative status of sheep and goats. Twenty-four studies identified via a systematic search conducted on four bibliographic databases were aggregated using random-effects models and results were displayed as standardized mean differences (SMDs) at 95% confidence interval. Pooled results revealed that dietary AP intervention increased dry matter intake (DMI) (SMD = 0.60; p < 0.05), average daily gain (ADG) (SMD = 1.44; p < 0.05) and reduced feed conversion ratio (SMD = − 1.08; p < 0.05) taking heterogeneity into consideration. The results also showed significant increase in concentrations of hemoglobin (SMD = 0.85; p < 0.05), hematocrits (SMD = 0.60; p < 0.05), red blood cell (SMD = 0.51; p < 0.05), and white blood cell (SMD = 2.15; p < 0.05) in comparison with the controls. Likewise, AP intervention improved blood antioxidative status, and aspects of serum biochemical values in small ruminants. The subgroup and meta-regression results revealed that moderators (ruminant type, breed, sex, feeding duration, body weight, diet type, supplementation level, and age) considered to influence the pooled results were significant predictors of AP effects on DMI, ADG and serum biochemical values, and accounted for most of the sources of heterogeneity. It is concluded that AP supplementation can enhances growth performance and blood characteristics in small ruminants, but further research is needed to determine optimal supplementation levels.