Effects of Different Generations and Sex on Physiological, Biochemical, and Growth Parameters of Crossbred Beef Cattle by Myostatin Gene-Edited Luxi Bulls and Simmental Cows

SIMPLE SUMMARY: The study described the effects of Myostatin gene editing on cattle to improve the growth and muscle development of hybrid cattle offspring. We focused on the Myostatin gene, which plays a crucial role in regulating muscle development. Gene editing could be able to enhance the size and performance of the crossbred cattle. The results showed that the Myostatin gene-edited cattle offspring displayed improved body size parameters, particularly body weight, cross height, and hip height, indicating the significant development of the hindquarters. The edited cattle have “double-muscled” forequarters and hindquarters with clear muscle masses, and their coat color reverted back to the original yellow. The study also found differences in blood glucose, calcium, and low-density lipoprotein levels, as well as a decrease in serum insulin levels in the edited cattle. Overall, the findings suggest that breeding with these Myostatin gene-edited bulls improve growth and performance in crossbred cattle, benefiting both farmers and consumers. ABSTRACT: (1) Background: Myostatin (MSTN) is a protein that regulates skeletal muscle development and plays a crucial role in maintaining animal body composition and muscle structure. The loss-of-function mutation of MSTN gene can induce the muscle hypertrophic phenotype. (2) Methods: Growth indexes and blood parameters of the cattle of different months were analyzed via multiple linear regression. (3) Results: Compared with the control group, the body shape parameters of F2 cattle were improved, especially the body weight, cross height, and hip height, representing significant development of hindquarters, and the coat color of the F2 generation returned to the yellow of Luxi cattle. As adults, MSTN gene-edited bulls have a tall, wide acromion and a deep, wide chest. Both the forequarters and hindquarters are double-muscled with clear muscle masses. The multiple linear regression demonstrates that MSTN gene-edited hybrid beef cattle gained weight due to the higher height of the hindquarters. Significant differences in blood glucose, calcium, and low-density lipoprotein. Serum insulin levels decreased significantly at 24 months of age. MSTN gene editing improves the adaptability of cattle. (4) Conclusions: Our findings suggest that breeding with MSTN gene-edited Luxi bulls can improve the growth and performance of hybrid cattle, with potential benefits for both farmers and consumers.