Long term conjugated linoleic acid supplementation modestly improved growth performance but induced testicular tissue apoptosis and reduced sperm quality in male rabbit

• Published in: PloS one 2020-01, Vol.15 (1), p.e0226070
• Main Authors: Abdelatty, A M, Badr, O A M, Mohamed, S A, Khattab, M S, Dessouki, Sh M, Farid, O A A, Elolimy, A A, Sakr, O G, Elhady, M A, Mehesen, G, Bionaz, M
• Format: Article
• Language: English
• Subjects: Animals; Apoptosis; Apoptosis - drug effects; Biology and Life Sciences; Body weight; Body Weight - drug effects; Carcinogens; Carnitine; Carnitine - metabolism; Diet; Dietary Supplements; Down-Regulation - drug effects; Epididymis - metabolism; Epididymis - pathology; Fatty acids; Fatty Acids, Unsaturated - metabolism; Fertility; Gene expression; Genetic engineering; Histopathology; Linoleic acid; Linoleic Acids, Conjugated - pharmacology; Lipids; Male; Medicine and Health Sciences; Morphology; Nutrition research; Parameters; Peroxisome proliferator-activated receptors; Polyunsaturated fatty acids; PPAR gamma - genetics; PPAR gamma - metabolism; Puberty; Rabbits; Research and Analysis Methods; Semen; Semen Analysis; Sperm; Sperm Motility - drug effects; Spermatogenesis; Spermatozoa - physiology; Stearoyl-CoA Desaturase - genetics; Stearoyl-CoA Desaturase - metabolism; Studies; Testes; Testis - metabolism; Testis - pathology; Testosterone - blood; Tissues; Tocopherol; Transcription; Transcriptome - drug effects; Up-Regulation - drug effects; Veterinary medicine; Vitamin E
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0226070

Conjugated linoleic acid (CLA) is known for its multiple benefits including improvement of growth, increasing lean mass, and anti-carcinogenic effects. However, when used in long-term supplementations CLA does not improve semen parameters in boar and bull and reduces fertility in Japanese quails. The content of unsaturated fatty acids in dietary lipids plays a significant role in spermatogenesis owning the high proportion of unsaturated fatty acids in plasma membrane of sperms. Whether CLA plays a role in testicular tissue and epididymal fat is still unknown. Therefore, in this study we hypothesize that long-term supplementation of equal proportion of CLA isomer mix (c9,t11-CLA and t10,c12- CLA) in rabbit bucks might alter male reproductive potentials. Twelve V-Line weaned male rabbits were used in 26 weeks trial, rabbits were individually raised and randomly allocated into three dietary groups. Control group (CON) received a basal diet, a group received 0.5% CLA (CLA 0.5%), and a group received 1% CLA (CLA 1%). Rabbits were euthanized at the end of the trial and several parameters were evaluated related to growth, semen quality, and testicular and epididymal tissue histopathology and transcriptome. The long-term supplementation of CLA increased feed intake by 5% and body weight by 2-3%. CLA 1% decreased sperm progressive motility. In testicular tissue L-carnitine and α-tocopherol were decreased by CLA supplementation. In epididymal fat, CLA tended to decrease concentration of polyunsaturated fatty acids, the expression of SCD5 gene was upregulated by CLA 1% and CASP3 gene was upregulated by CLA 0.5%. Transcription of PPARG was downregulated by CLA. Feeding 1% CLA also decreased testicular epithelial thickness. Long-term supplementation of CLA modestly enhanced male rabbit growth, but negatively impacted male reproduction, especially at high dose of CLA.