d-Aspartate amends reproductive performance of aged roosters by changing gene expression and testicular histology
Mahdi Ansari A , Mahdi Zhandi A F , Hamid Kohram A B , Mojtaba Zaghari A , Mostafa Sadeghi A , Maedeh Gholami C , Hamid Deldar C , Maria Maddalena Di Fiore D and Andrew Parks Benson E
+ Author Affiliations
- Author Affiliations
A Department of Animal Science, College of Agriculture and Natural Resources, University of Tehran, Karaj 31587-77871, Iran.
B Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Chamran University, Ahvaz 83151-61357, Iran.
C Department of Animal Science, College of Animal Science and Fisheries, Sari Agricultural Science Natural Resources University, Sari 4818168984, Iran.
D Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania Luigi Vanvitelli, via Vivaldi, 43, 81100 Caserta, Italy.
E Department of Poultry Science, University of Georgia, Athens, GA 30602-2772, USA.
F Corresponding author. Email: mzhandi@ut.ac.ir
Reproduction, Fertility and Development 30(7) 1038-1048 https://doi.org/10.1071/RD17072
Submitted: 26 February 2017 Accepted: 28 November 2017 Published: 5 January 2018
Abstract
Male broiler breeders (n = 32) of 55 weeks of age were administered four different doses of capsulated d-aspartate (DA; 0, 100, 200 or 300 mg kg−1 day−1, p.o. (DA0, DA100, DA200 and DA300 respectively)) for 12 successive weeks to assess reproductive performance, blood testosterone, testicular histology and transcript levels of steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme (P450scc), androgen receptor (AR), LH receptor (LHR), 3β-hydroxysteroid dehydrogenase (3BHSD), proliferating cell nuclear antigen (PCNA), glutamate ionotropic receptor NMDA type subunit 1 (GRIN1) and glutamate ionotropic receptor NMDA type subunit 2B (GRIN2B). Blood samples and ejaculates were collected, and bodyweight was recorded weekly for 10 weeks. AI was performed weekly for the last 2 weeks to determine the number of sperm penetration holes in the perivitelline layer, fertility and hatchability. Testes histology and transcript levels were evaluated in the 12th week. Bodyweight, numbers of Leydig cells and blood vessels, testis index and levels of sperm abnormalities were not affected (P > 0.05) by the treatment. However, sperm total and forward motility, plasma membrane integrity and functionality of sperm, ejaculate volume, testosterone concentration and fertility were higher (P < 0.05) in both the DA200 and DA300 groups compared with the other groups. In the DA100 and DA200 groups, sperm concentration, number of spermatogonia, thickness of the seminiferous epithelium and the diameter of tubules were significantly higher (P < 0.05) than the other DA-treated groups. The number of penetration holes, hatchability and malondialdehyde concentration were higher in the DA200, all DA-treated and DA300 groups respectively compared with the control and other treatment groups. Except for P450scc, AR, LHR and PCNA transcript levels in the DA300 groups, the relative expression of the genes evaluated improved significantly in the other DA-treated groups. Based on these experimental findings, it is concluded that DA improves reproductive performance of aged roosters.
Additional keywords: fertility, hatchability, spermatogenesis, steroidogenesis.
References
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