title: Effects of guanidinoacetic acid diet supplementation on semen quality and fertility of broiler breeder roosters.
abstract: Decreased semen quality and fertility rate is a common feature in broiler breeder roosters. This decrease is associated with dysfunction of Sertoli cells and defective spermatogenesis. Guanidinoacetic acid (GAA), as a precursor of creatine, plays an important role in the proper functioning of Sertoli cells and energy metabolism in sperm. Twenty, 29-wk-old broiler breeder roosters (Ross 308) were randomly allotted to 4 treatment groups and fed diets supplemented with different levels of GAA, including 0 (GAA-0), 600 (GAA-600), 1200 (GAA-1200), and 1800 (GAA-1800) mg GAA/kg of diet for 26 successive weeks. During a 24-wk period, the seminal characteristics were weekly evaluated. At the end of experiment, sperm penetration and fertility rates were determined, using 68 artificially inseminated age-matched broiler breeder hens of the same strain (for 2 weeks). Semen concentration (P = 0.003), total sperm number (P = 0.005) and sperm forward motility (P = 0.01) were increased by GAA-1200 group. Also, sperm plasma membrane functionality was marginally affected (P = 0.06) in roosters received all levels of GAA. Sperm abnormality and plasma membrane integrity were not affected by dietary GAA. The highest number of sperm penetration holes was recorded for the GAA-1200 group (P = 0.08). Interestingly, fertility rate was increased by the feeding of all levels of GAA (P = 0.01). In conclusion, dietary GAA was associated with improvement in most of the rooster's seminal characteristics and fertility rate, suggesting a potential for using GAA to attenuate the age-related sub-fertility in commercial broiler breeder roosters.
authors.affiliation: Department of Animal Science, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.
authors.forename: Ramin Shahabi
authors.initials: RS
authors.lastname: Tapeh
authors.affiliation: Department of Animal Science, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran. Electronic address: mzhandi@ut.ac.ir.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Zhandi
authors.affiliation: Department of Animal Science, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Zaghari
authors.affiliation: Department of Animal Science, College of Agriculture, Shiraz University, Shiraz, Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Akhlaghi
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000187:drug effects; D002645:Chickens / Q000502:physiology*; D019587:Dietary Supplements; D005298:Fertility / Q000187:drug effects*; D005998:Glycine / Q000031:analogs & derivatives* / Q000494:pharmacology; D007315:Insemination, Artificial / Q000662:veterinary; D008297:Male; D055101:Semen Analysis / Q000662:veterinary*
chemical_list: C004946:glycocyamine; D005998:Glycine
keywords: Aging; Artificial insemination; Chicken; Fertility; Sperm