Bergamot by-products for lamb feeding: Effects on growth performance and meat quality.

The demand for meat has increased steadily during the past decades, representing a challenge for the future. In this scenario, the use of local agro-industrial by-products as replacers of conventional feedstuff may be a strategy to reduce the environmental impact of livestock sector, mitigate emission for feed transportation, and limit feeding cost, following a circular economy approach. In light of the above, this study aimed to evaluate the effects of dietary inclusion of various bergamot by-products, cultivated in Mediterranean region, on growth performance and meat quality of lambs. Thirty 40-days old male lambs (15.0 ± 1.79 kg initial body weight) were selected and assigned to three experimental groups. The first group were fed a conventional (CON) diet, formulated as follows: corn (43%), hay (30%), soybean meal (22%), molasses (3%), and vitamin-mineral (2%). The second one (BER) received the CON diet with 10% of dried bergamot pulp. The third group (FIB) received CON diet with 10% of the residual of dried bergamot pulp after phenolic extraction. The bergamot by-products partially replaced the corn counterpart. On day 50 of the feeding trial, lambs were weighed and sacrificed in a local slaughterhouse. After 24h cold carcasses were weighed and Longissimus thoracis et lumborum muscles were collected from each side of the carcass for subsequent analyses. Data were statistically analyzed using a mixed model. The daily intake of the experimental diets was not affected by treatments (P>0.050; 765, 820, and 808 g DM/day for CON, BER, and FIB respectively). Similar feed intake also corresponded to similar growth performances among experimental groups, indeed final body weight, hot and cold carcass weight, and average daily gain did not show significant differences (P>0.050). Also, pH of rumen and abomasum were not influenced by dietary treatment (P>0.050). Concerning analyses on fresh meat quality, the water holding capacity, the drip loss (48 and 96 h), and the cooking loss were assessed, but none of them were significantly affected (P>0.050). Also, the meat color was evaluated during a shelf-life trial over 7 days of refrigerated storage, but the results were comparable between dietary treatment (P>0.050). Bergamot by-products may be implemented in lamb diet without negatively affecting growth performance. However, we hypothesized that bioactive compounds present in bergamot may influence metabolism of lambs modifying some meat quality traits. Further analyses are ongoing to clarify this hypothesis