Effects of Dietary Machine-Harvested Cotton Residue on Growth Performance, Slaughter Performance, Meat Quality and Serum Biochemical Indices of Meat Rabbits

This experiment was conducted to investigate the effects of different dietary levels of machine-har- vested cotton residue on growth performance, slaughter performance, organ indices, meat quality and serum biochemical indices of meat rabbits. A total of 120 healthy 35-day-old weaned Ila meat rabbits with similar body weight were randomly divided into 4 groups, which were fed a basal diet supplemented with 0 (control group), 10%, 20% and 30% machine-harvested cotton residue, respectively, with 5 replicates in each group and 6 rabbits (half male and half female) in each replicate. The pre-trial period lasted for 7 days and the exper- imental period lasted for 60 days. The results showed as follows: 1) dietary machine-harvested cotton residue had no significant effects on the average daily feed intake, diarrhea rate and mortality of meat rabbits (P > 0.05) . Compared with the control group, the final body weight and feed to gain ratio in 10% machine-harves- ted cotton residue supplemental group were significantly increased (P<0.05), and the ratio of feed to gain was significantly decreased (P<0.05) . 2) The live weight before slaughter and full eviscerated ratio of meat rabbits in 10% machine-harvested cotton residue supplemental group were significantly higher than those in 20% and 30% machine-harvested cotton residue supplemental group groups (P<0.05), the half carcass weight and full carcass weight were significantly higher than those in the control group and 30% machine-harvested cotton resi- due supplemental group (P<0.05), and the half eviscerated ratio was significantly higher than that in the other groups (P<0.05) . 3) Dietary machine-harvested cotton residue had no significant effects on the heart index, kidney index, spleen index and thymus index of meat rabbits (P>0.05) . The liver index in 30% machine-har- vested cotton residue supplemental group was significantly higher than that in the control group and 10% and 20% machine-harvested cotton residue supplemental groups (P<0.05), and there was no significant difference in liver index in 10% and 20% machine-harvested cotton residue supplemental group compared with the control group (P>0.05) . 4) Dietary machine-harvested cotton residue had no significant effects on the pH, meat col- or, drip loss and shear force in longissimus dorsi of meat rabbits (P>0.05) . The cooking loss in longissimus dorsi in 10% machine-harvested cotton residue supplemental group was significantly lower than that in the con- trol group and 30% machine-harvested cotton residue supplemental group (P<0.05) . 5) The serum urea nitro- gen content of meat rabbits in 30% machine-harvested cotton residue supplemental group was significantly high- er than that in the control group and 10% machine-harvested cotton residue supplemental group (P < 0. 05), and there was no significant difference between the control group and 10% machine-harvested cotton residue supplemental group (P>0.05); the serum activities of alanine aminotransferase and aspartate aminotransferase in 20% and 30% machine-harvested cotton residue supplemental group were significantly higher than those in the control group (P<0.05) . In conclusion, dietary supplemented with appropriate level of machine-harvested cotton residue can improve the growth performance, slaughter performance and meat quality of meat rabbits, and has no negative effects on organ indices and serum biochemical indices, and the appropriate supplemental level is 10%. © 2025 Chinese Journal of Animal Science and Veterinary Medicine Co., Ltd.. All rights reserved.