Growth performance, meat quality, and blood characteristics of finisher crossbred pigs fed diets supplemented with different levels of green tea (Camellia sinensis) by-products

Background and Aim: Dietary supplementation with green tea by-product shows special effects on animal parameters. This study aimed to assess the effects of green tea by-products (GTBP) in the diet on some blood parameters, growth performance, and carcass characteristics of finishing pigs and on meat quality, and nutritional composition of pork. Materials and Methods: One hundred and sixty crossbred pigs with an initial body weight of 65.15 ± 0.38 kg, were distributed into four dietary treatments, with four replicates of 10 pigs each. The dietary treatments were a basal diet (control diet, CON), and three experimental diets (GTBP8, GTBP16, and GTBP24) based on the CON diet supplemented with GTBP at 8, 16, and 24 g/kg of feed. The studied parameters were examined during the experimental period of 10 weeks. Results: No statistical differences in average daily feed intake, average daily gain, and feed conversion ratio were observed between the diet treatments (p > 0.05). Backfat thickness decreased (linear, p < 0.05) according to the GTBP levels but no other carcass parameters. Meat quality was not influenced by the GTBP levels (p > 0.05). However, pigs fed with GTBP had a decrease in cholesterol content and an increase in crude protein and total omega-3 content of pork compared to the CON diet (p < 0.05). Moreover, dietary supplementation with GTBP significantly decreased plasma cholesterol (p < 0.05), and trends for the decrease in low-density lipoprotein cholesterol and urea nitrogen were observed (linear, p = 0.08). Conclusion: Up to 24 g/kg GTBP in the diet for finishing pigs does not impair animal performance and makes carcass leaner with softer meat as well as positive effects on cholesterol and fatty acid metabolism. Further experiments are needed to determine the optimal levels of GTBP addition in finishing pig diet to produce higher meat quality.