Relationship of Dietary Fat Sources with Semen Characteristics, Blood Plasma Metabolites and Scrotal Circumference in Mature Rams

Document Type : Research Article


1 Department of Animal Science, Faculty of Agricultural Science, University of Guilan, Rasht, Iran

2 Department of Animal Science, Faculty of Agriculture, University of Isfehan, Isfehan, Iran


The hypothesis of this experiment was that the various sources of dietary fat with different dietary ratios of polyunsaturated fatty acids (PUFAs) to saturated fatty acids (SFAs) would alter the reproduction parameters of mature rams. Twelve mature rams were randomly allotted to one of four dietary treatments in a completely randomized design. Dietary treatments were: 1) ration with 4% soybean oil (SOY-OIL), 2) ration with 8% full fat soybean (FULL-FAT), 3) ration with 4% calcium salts of soybean oil (Ca-SALT) and 4) ration with 4% tallow (TALL). All diets were kept isoenergetic and isonitrogenous and formulated to be similar in Ca and P contents, while meeting or exceeding the Cornell Net Carbohydrate and Protein System software requirements for the rams used in this study. Diets were supplied to the rams during four months (from August to late December). Semen characteristics, scrotal circumference, and concentrations of cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglyceride and testosterone of plasma were measured at the end of the experimental period. Based on the results of this study, diets supplemented with Ca-SALT and TALL improved the health of plasma membrane, viability and sperm concentration (P<0.05). Rams supplemented with Ca-SALT had also greater volume of semen and total sperm count in ejaculate (P<0.05) which are two important factors determining the sperm quality. There was no beneficial effect for different treatments based on spermatozoa motility (P>0.05). Blood concentrations of cholesterol, LDL and HDL of rams supplemented with Ca-SALT were significantly higher than the other treatments. Concentrations of triglyceride, testosterone and scrotal circumference were not affected by the experimental treatments (P>0.05). As an overall conclusion, the results of this study have indicated the benefits for adding Ca-SALT to the diets of adult rams on their reproductive performance.


Aksoy Y., Aksoy H., Altinkaynak K., Aydin H.R. and Ozkan A. (2006). Sperm fatty acid composition in subfertile men. Prostaglandins Leukot. Essent. Fatty Acid. 75(2), 75-79.
Amidi F., Farshad A. and Khor A.K. (2010). Effects of cholesterol-loaded cyclodextrin during freezing step of cryopreservation with TCGY extender containing bovine serum albumin on quality of goat spermatozoa. Cryobiology. 61(1), 94-99.
Andrae J.G., Hunt C.W., Duckett S.K., Kennington L.R., Feng P., Owens F.N. and Soderlund S. (2000). Effect of high-oil corn on growth performance, diet digestibility, and energy content of finishing diets fed to beef cattle. J. Anim. Sci. 78(9), 2257-2262.
Bjorndahle L., Sonderlund I. and Kvist U. (2003). Evaluation of the one-step eosin-nigrosin staining technique for human sperm vitality assessment. Hum. Reprod. 18(4), 813-816.
Blesbois E., Lessire M., Grasseau I., Hallouis J.M. and Hermier D. (1997). Effect of dietary fat on the fatty acid composition and fertilization ability of fowl semen. Biol. Reprod. 56(5), 1216-1620.
Brinsko S.P., Varner D.D., Love C.C., Blanchard T.L., Day B.C. and Wilson M.E. (2005). Effect of feeding a DHA-enriched nutriceutical on the quality of fresh, cooled and frozen stallion semen. Theriogenology. 63, 1519-1527.
Calsamiglia S., Busquet M., Cardozo P.W., Castillejos L. and Ferret A. (2007). Invited review: essential oils as modifiers of rumen microbial fermentation. J. Dairy Sci. 90(6), 2580-2595.
Cerolini S., Pizzi F., Gliozzi T., Maldigian A., Zaniboni L.and Parodi L. (2003). Lipid manipulation of chicken semen by dietary means and its relation to fertility: a review. World's Poult. Sci. J. 59, 65-75.
Coppock C.E. and Wilks D.L. (1991). Supplemental fat in high-energy rations for lactating cows: effects on intake, digestion, milk yield, and composition. J. Dairy Sci. 69(9), 3826-3837.
Darin-Bennett A. and White I.G. (1977). Influence of the cholesterol content of mammalian spermatozoa on susceptibility to cold-shock. Cryobiology. 14(4), 466-470.
Evans G. and Maxwell W.M.C. (1987). Handling and examination of semen. Pp. 97-98 in Salamon’s Artificial Insemination of Sheep and Goats. G. Evans and W.M.C. Maxwell, Eds. Butterworths, Boston, USA.
Felton E.E. and Kerly M.S. (2004). Performance and carcass quality of steers fed different sources of dietary fat. J. Anim. Sci. 82(6), 1794-1805.
Garcia-Artiga C. (1994). Test de endosmosis en ovino. Pp. 77-81 in Proc. 7th Int. Meet. Anim. Reprod., Murcia, Spain.
Glazar A.I., Mullen S.F., Liu J., Benson J.D., Critser J.K., Squires E.L. and Graham J.K. (2009). Osmotic tolerance limits and membrane permeability characteristics of stallion spermatozoa treated with cholesterol. Cryobiology. 59(2), 201-206.
Gliozzi T.M., Zaniboni L., Maldjian A., Luzi F., Maertens L. and Cerolini S. (2009). Quality and lipid composition of spermatozoa in rabbits fed DHA and vitamin E rich diets. Theriogenology. 71(6), 910-919.
Hristov A.N., Vander Pol M., Agle M., Zaman S., Schneider C., Ndegwa P., Vaddella V.K., Johnson K., Shingfield K.J. and Karnati S.K. (2009). Effect of lauric acid and coconut oil on ruminal fermentation, digestion, ammonia losses from manure, and milk fatty acid composition in lactating cows. J. Dairy Sci. 92(11), 5561-5582.
Jeyendran R.S., Van der Ven H.H. and Zaneveld L.J. (1992). The hypoosmotic swelling test: an update. Arch. Androl. 29(2), 105-116.
Lopez N.C., Scarpa A.B., Cappelloza B.I., Cooke R.F. and Vasconcelos J.L.M. (2009). Effects of rumen-protected polyunsaturated fatty acid supplementatian on reproductive performance of Bosindiscus beef cows. J. Anim. Sci. 87(12), 3935-3943.
Miller J.R.R., Sheffer C.J., Cornett C.L., Mc Clean R., Mac Callum C. and Johnston S.D. (2004). Sperm membrane fatty acid composition in the Eastern grey kangaroo (Macropus giganteus), koala (Phascolarctos cinereus) and common wombat (Vombatus ursinus) and its relationship to cold shock injury and cryopreservation success. Cryobiology. 49(2), 137-148.
Mitre R., Cheminade C., Allaume P., Legrand P. and Legrand A.B. (2004). Oral intake of shark liver oil modifies lipid composition and improves motility and velocity of boar sperm. Theriogenology. 62, 1557-1566.
Moce E., Purdy P.H. and Graham J.K. (2010). Treating ram sperm with cholesterol-loaded cyclodextrins improves cryosurvival.
      Anim. Reprod. Sci. 118(2), 236-247.               
Mui~no-Blanco T., Perez-Pe R. and Cebrian-Perez J.A. (2008). Seminal plasma proteins and sperm resistance to stress. Reprod. Domest. Anim. 4, 18-31.
Ramirez J.E. and Zinn R.A. (2000). Interaction of dietary magnesium level on the feeding value of supplemental fat in finishing diets for feedlot steers. J. Anim. Sci. 78(8), 2072-2080.
Rooke J.A., Shao C.C. and Speake B.K. (2001). Effects of feeding tuna oil on the lipid composition of pig spermatozoa and in vitro characteristics of semen. Reproduction. 121(2), 315-322.
Safarinejad M.R., Hosseini S.Y., Dadkhah F. and Asgari M.A. (2010). Relationship of omega-3 and omega-6 fatty acids with semen characteristics and anti-oxidant status of seminal plasma: a comparison between fertile and infertile men. Clin. Nutr. 29(1), 100-105.
SAS Institute. (1996). SAS®/STAT Software, Release 6.11. SAS Institute, Inc., Cary, NC. USA.
Strzezek J., Fraser L., Kuklińska M., Dziekońska A. and Lecewicz M. (2004). Effects of dietary supplementation with polyunsaturated fatty acids and antioxidants on biochemical characteristics of boar semen. Reprod. Biol. 4(3), 271-287.
Surai P.F., Noble R.C., Sparks N.H. and Speake B.K. (2000). Effect of long-term supplementation with arachidonic or docosahexaenoic acids on sperm production in the broiler chicken. J. Reprod. Fertil. 120(2), 257-264.
Vafa T.S., Naserian A.A., Heravi Moussavi A.R., Valizadeh R. and Danesh Mesgaran M. (2009). Effect of different levels of fish oil and canola oil on in vitro and in vivo nutrient digestibility. Res. J. Biol. Sci. 4(12), 1221-1226. 
Walters E.M., Rieke A., Graham J.K. and Critser J.K. (2008). Improved osmotic tolerance limits of boar spermatozoa treated with cholesterol-loaded methylcy-B-clodextrin. Theriogenology. 70(8), 1394-1395.