title: Immunization of dogs with recombinant GnRH-1 suppresses the development of reproductive function.
abstract: This study was designed to evaluate the effect of active immunization using recombinant GnRH-I protein on reproductive function in dogs. Six male and six female dogs were randomly assigned to either a control group or an immunization group (n = 3 males or 3 females/group). Dogs (aged 16 weeks) were immunized against GnRH-I with a maltose-binding protein-gonadotropin-releasing hormone I hexamer generated by recombinant DNA technology. Blood samples were taken at 4-week intervals after immunization. The serum concentrations of testosterone and estradiol and anti-GnRH-I antibodies were determined by RIA and ELISA, respectively. The results showed that active immunization with recombinant GnRH-I increased the serum levels of anti-GnRH antibodies (P < 0.05) and reduced the serum concentrations of testosterone (P < 0.05) and estradiol (P < 0.05) as compared with the controls. At 28 weeks of age, testes and ovaries were taken surgically for morphologic evaluation. Histologic studies performed on testicular and ovarian tissues revealed clear signs of atrophy in the recombinant GnRH-I-immunized dogs and a significant reduction (P < 0.05) in the weights and sizes of paired testes and ovaries in the treated dogs. Microscopically, spermatogonia were visible, but no spermatids and spermatozoa were detected in the seminiferous tubules. Neither early antral nor antral follicles were found in the immunized group. These results demonstrate that recombinant GnRH-I is an effective immunogen in dogs.
authors.affiliation: Anhui Provincial Laboratory of Animal Genetic Resources Protection and Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Anhui Provincial Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Engineering Research Center of Reproduction and breeding in Sheep of Anhui Province, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Anhui Provincial Laboratory of Animal Genetic Resources Protection and Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Anhui Provincial Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Engineering Research Center of Reproduction and breeding in Sheep of Anhui Province, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Anhui Provincial Laboratory of Animal Genetic Resources Protection and Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Xijie
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Anhui Provincial Laboratory of Animal Genetic Resources Protection and Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Shudong
authors.initials: S
authors.lastname: Jiang
authors.affiliation: Anhui Provincial Laboratory of Animal Genetic Resources Protection and Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Fubao
authors.initials: F
authors.lastname: Li
authors.affiliation: Anhui Provincial Laboratory of Animal Genetic Resources Protection and Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Anhui Provincial Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Engineering Research Center of Reproduction and breeding in Sheep of Anhui Province, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Yunhai
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Anhui Provincial Laboratory of Animal Genetic Resources Protection and Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Anhui Provincial Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Engineering Research Center of Reproduction and breeding in Sheep of Anhui Province, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Xiaorong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Anhui Provincial Laboratory of Animal Genetic Resources Protection and Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Anhui Provincial Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Engineering Research Center of Reproduction and breeding in Sheep of Anhui Province, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Yunsheng
authors.initials: Y
authors.lastname: Li
authors.affiliation: Anhui Provincial Laboratory of Animal Genetic Resources Protection and Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Anhui Provincial Laboratory of Animal Genetic Resources Protection and Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Anhui Provincial Laboratory for Local Livestock and Poultry Genetic Resource Conservation and Bio-Breeding, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China; Engineering Research Center of Reproduction and breeding in Sheep of Anhui Province, College of Animal Sciences and Technology, Anhui Agricultural University, Hefei, Anhui, China. Electronic address: fgfang@163.com.
authors.forename: Fugui
authors.initials: F
authors.lastname: Fang
mesh_terms: D000818:Animals; D004285:Dogs; D004958:Estradiol / Q000097:blood; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000276:immunology*; D007114:Immunization / Q000379:methods / Q000662:veterinary*; D008297:Male; D009929:Organ Size; D010053:Ovary / Q000033:anatomy & histology; D011993:Recombinant Fusion Proteins / Q000276:immunology*; D012098:Reproduction / Q000276:immunology*; D012741:Sexual Maturation; D013245:Sterilization, Reproductive / Q000379:methods / Q000662:veterinary*; D013737:Testis / Q000033:anatomy & histology; D013739:Testosterone / Q000097:blood
chemical_list: D011993:Recombinant Fusion Proteins; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D004958:Estradiol
keywords: Active immunization; GnRH-I; Reproductive function; dog