Effects of supplemental conjugated linoleic acids (CLA) on fresh and post‐thaw sperm quality of Holstein bulls

Abstract

This study was designed to investigate the effects of feeding-protected conjugated linoleic acid (CLA) on the semen production and sperm freezability in Holstein bulls. Twelve bulls were randomly assigned to two groups (n = 6 per group). Bulls received the normal diet (control group) or the normal diet top-dressed with 50 g of CLA (treated group) for 10 weeks. The control group received 40 g/day calcium soap of fatty acid. Fresh and post-thaw semen quality was assessed on ejaculates collected at the 0, 4, 6, 8 and 10 week of supplementation. Semen evaluations including sperm concentration, motion characteristics (subjective and computer-assisted), viability (Eosin-Nigrosin), membrane integrity (hypo-osmotic swelling test) and abnormality were conducted. Semen volume, sperm concentration and total sperm output were not affected by dietary treatment (p > .05). The proportion of spermatozoa with abnormal morphology in fresh semen significantly increased (p < .05) in the CLA-fed group compared to control group. Also, in CLA-fed group, the proportion of post-thaw spermatozoa with abnormal morphology at week 10 of trial was significantly higher in CLA than control group (p < .05). Progressive motility tended to be increased in the CLA-fed group, although dietary supplementation did not affect other CASA parameters or viability in fresh and frozen-thawed sperm. In this study, CLA supplementation had little positive effect on fresh or post-thaw sperm quality of Holstein bulls.

Influence of various dietary fat sources on freezing capacity of Moghani ram semen

“…The current results are in agreement with studies in ruminants (Masoudi et al, 2016;Tran et al, 2016) and humans (Vireque et al, 2016;Ferramosca et al, 2017). However, other researchers reported different results (Mourvaki et al, 2010;Karimi et al, 2017). Khoshvaght et al (2016) concluded that feeding FO could improve the quality of fresh and frozen thawed semen by altering the sperm membrane fatty acid composition.…”

“…Based on the current results, feeding the rams with the addition of FO and PF could increase the seminal volume compared with that of the control, but it did not have significant effects on sperm concentration. Karimi et al (2017) showed that CLA could not increase bull semen volume and spermatozoa concentration. A probable reason or mechanism for seminal volume increasing with PUFAs is the synthesis and secretion of seminal plasma (Rooke et al, 2001;Khoshvaght et al, 2016).…”

“…On the other hand, lipid composition of the diet could alter fatty acid composition of the semen and plasma membrane of spermatozoa (Blesbois et al, 1997). PUFAs enhance frozen (Gürler et al, 2015) or fresh (Karimi et al, 2017) sperm quality by improving the fluidity of the plasma membrane lipids of the sperm head, body and tail. Increasing fluidity is necessary for sperm motility, plasma membrane integrity and functionality.…”

“…Many studies have demonstrated that dietary n-3 and n-6 fatty acids enhance the preservation of spermatozoa after cold shock and ice crystal formation in humans (Vireque et al, 2016), bulls (Gholami et al, 2010;Khoshvaght et al, 2016), goats (Dolatpanah et al, 2008), stallions (Rodrigues et al, 2017) and roosters (Cerolini et al, 2006). On the other hand, Karimi et al (2017) demonstrated that supplementation of the diet of bulls with conjugated linoleic acid (CLA) did not affect fresh and frozen semen quality. To the best of the authors' knowledge, there is a dearth of information about the effects of dietary supplementation of n-3 and n-6 fatty acids on sperm motion kinematics in rams.…”

Conjugated linoleic acid as a potential bioactive molecule to modulates gamete and embryo cryotolerance

“…A similar result was also observed by Karimi et al (59) in Holstein bulls. Evaluating the effect of CLA supplementation in the diet on the quality and freezability of sperm, the authors did not observe the effect of CLA on semen volume, sperm concentration and total sperm production (p> 0.05).…”