This research sought to evaluate the potential effects of probiotics and yeast cell wall (YCW) supplements on the liver functionality index (LFI) and metabolic parameters of dairy cattle throughout the transitional period. A cohort of forty dry cows was randomly divided into four groups, namely the probiotic group (Pr) receiving a basal diet combined with a blend of Bacillus subtilis, Bacillus lechiniformis, Streptococcus Thermophilis, and Enterococcus faecium
the YCW group receiving a basal diet enriched with Saccharomyces cerevisiae
the probiotic and yeast cell wall extract group (P & Y) receiving a basal diet supplemented with a mixture of probiotic and yeast cell wall extract
and the control group adhering to the basal diet. The intervention was initiated 21 days before calving and persisted until 28 days post-calving, except for the control group. The study entailed the collection of blood samples at four sampling times, encompassing 21 days preceding calving, seven days before calving, seven days post-calving, and four weeks post-calving. Multiple biochemical parameters were assessed, including urea, blood urea nitrogen (BUN), Gamma-glutamyl transferase (GGT), total bilirubin (TB), albumin, total protein (TP), globulin, glucose, triglyceride, cholesterol, and liver functionality index. The results showed that the Pr group exhibited reduced average levels of GGT and glucose compared to the control group (P <
0.05). Similarly, the P & Y group demonstrated lower average BUN, TB, and cholesterol levels than the control (P <
0.05). Notably, the LFI exhibited a discernible trend towards elevation in the Pr group compared to the control group (P = 0.007) and the P & Y group (P = 0.007). In essence, supplementation of YCW and probiotics is associated with advantageous effects on metabolic parameters and liver function.