A meta-analysis of essential oils as a dietary additive for weaned piglets: Growth performance, antioxidant status, immune response, and intestinal morphology

A Meta-Analysis of 3-Nitrooxypropanol Dietary Supplementation on Growth Performance, Ruminal Fermentation, and Enteric Methane Emissions of Beef Cattle

“…Covariates were divided as follows: (1) 3-NOP doses 35-100 and 101-280 mg/kg DM; (2) 3-NOP supplementation period ≤ 60 and >60 days; and (3) amount of concentrate included in the diet ≤ 700 and >700 g/kg DM. When a significant effect (p < 0.05) of any covariate was detected, the WMD of the response variable was evaluated through subgroup analysis, as suggested by other authors [27,46].…”

Capsaicin as a Dietary Additive for Dairy Cows: A Meta-Analysis on Performance, Milk Composition, Digestibility, Rumen Fermentation, and Serum Metabolites

“…Subsequently, the following information was extracted from each document: (1) breed of dairy cows; (2) days in milk that the cows had; (3) CAP dose (mg/kg DM); (4) duration of CAP supplementation period (days); and (5) amount of forage (g/kg DM) included in the experimental diets. The final database only included response variables reported in at least three scientific articles, as recommended by other authors [27,28,34]. The included variables were grouped as follows: (1) dry matter intake (DMI), milk yield (MY), milk yield corrected to 4% fat content (4FCMY), feed efficiency (FE), milk fat yield (MFY), milk protein yield (MPY), milk lactose yield (MLY), milk fat content (MFC), milk protein content (MPC), milk lactose content (MLC), total solids (TS) in milk, milk urea nitrogen (MUN), and milk somatic cell count (SCC); (2) apparent dry matter digestibility (ADMD), apparent organic matter digestibility (AOMD), apparent crude protein digestibility (ACPD), apparent neutral detergent fiber digestibility (ANDFD), apparent acid detergent fiber digestibility (AADFD), ammonia nitrogen (NH 3 -N), total volatile fatty acids (TVFA), acetate, propionate, butyrate, and valerate; (3) glucose, urea, beta-hydroxybutyrate (BHB), and non-esterified fatty acids (NEFA).…”

“…Furthermore, some authors [26] mention that traditional reviews commonly lead to biased conclusions because they do not quantitatively evaluate the studies included in them. In contrast, according to several authors [27][28][29], meta-analysis is an effective method to quantitatively analyze studies on the same topic with contradictory findings and obtain reliable conclusions. To our knowledge, the effects of dietary CAP supplementation in dairy cows have not been evaluated by meta-analysis.…”