Preliminary evaluation of a commercially available GnRH-based immunocontraceptive

Milena  Rocha; Mauricio Favoreto; Barbara Loureiro

doi:10.58292/CT.v18.13815

Milena Rocha Laboratory of Animal Reproductive Physiology, College of Veterinary Medicine, University of Vila Velha, Vila Velha, ES, Brazil
Mauricio Favoreto Laboratory of Animal Reproductive Physiology, College of Veterinary Medicine, University of Vila Velha, Vila Velha, ES, Brazil; and Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA
Barbara Loureiro Laboratory of Animal Reproductive Physiology, College of Veterinary Medicine, University of Vila Velha, Vila Velha, ES, Brazil; and Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA

DOI: https://doi.org/10.58292/CT.v18.13815

Keywords: GnRH, immunocontraceptive, ovary, follicle, pregnancy

Abstract

Stray dog population control is a global concern due to its implications for public health and animal welfare. Immunocastration relies on the immunological blockade of gonadotropin releasing hormone (GnRH) and represents a viable alternative to surgical sterilization. We evaluated the effects of a commercially available immunocontraceptive on ovarian activity in prepubertal female dogs; 4 were treated with antiGnRH (2 treatments, 4 weeks apart) and 3 served as controls. Dogs were monitored for signs of estrus for 7-8 months after the second treatment and progesterone concentrations were determined. Ovaries and uterus were collected after ovariohysterectomy. None of the dogs had lesions or discomfort related to treatment; 3 out of 4 treated dogs did not have estrus until surgery (13-14 months of age) and 1 had estrus at 13 months; this dog had a corpus luteum and high progesterone concentrations. Ovaries were larger and had more follicles in treated dogs whereas endometrium was thicker in control. Commercially available antiGnRH can be a tool for reproductive management in prepubertal female dogs; however, further research is needed to confirm the long-term safety and duration of the contraceptive effect.

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References

1.
Belo V, Struchiner C, Werneck G, et al: Abundance, survival, recruitment and effectiveness of sterilization of free-roaming dogs: a capture and recapture study in Brazil. PLoS One 2017:12. doi: 10.1371/journal.pone.0187233

2.
Qian C, Jiang C, Hou J: The endometrium histopathology and cell ultrastructure in bitches with pyometra induced using progesterone and Escherichia coli. Tissue Cell 2020;67:101414. doi: 10.1016/j.tice.2020.101414

3.
Felisbina L. Queiroga, Maria D, et al: Crosstalk between GH/IGF-I axis and steroid hormones (progesterone, 17β-estradiol) in canine mammary tumours. J Steroid Biochem Mol Biol 2008:110. doi: 10.1016/j.jsbmb.2008.02.005

4.
Donovan CE, Greer M, Kutzler MA: Physiologic responses following gonadotropin-releasing hormone immunization in intact male dogs. Reprod Domest Anim 2012;47:403–405. doi: 10.1111/rda.12017

5.
Dobson H, Campbell BK, Scaramuzzi RJ: Use of a GnRH antagonist in conjunction with low amplitude, high frequency LH pulses to induce follicular growth without an LH surge and ovulation in ewes. Anim Reprod Sci 1997;46:213–222. doi: 10.1016/s0378-4320(96)01624-7

6.
Oonk HB, Turkstra JA, Schaaper WMM, et al: New GnRH-like peptide construct to optimize efficient immunocastration of male pigs by immunoneutralization of GnRH. Vaccine 1998;16:1074–1082. doi: 10.1016/s0264-410x(98)80101-1

7.
Lents MP, Barbosa LP, Santana ALA, et al: Immunocastration of goats using anti-gonadotropin-releasing hormone vaccine. Theriogenology 2018;114:7–13. doi: 10.1016/j.theriogenology.2018.03.013

8.
Fischer A, Benka VA, Briggs J: Effectiveness of GonaCon as an immunocontraceptive in colony-housed cats. J Feline Med Surg 2018;20:786–792. doi: 10.1177/1098612X18758549

9.
Han XF, Cao XH, Tang J, et al: Active immunization against GnRH reduces the synthesis of GnRH in male rats. Theriogenology 2013;80:1109–1116. doi: 10.1016/j.theriogenology.2013.08.014

10.
Vargas-Pino F, Gutiérrez-Cedillo V, Canales-Vargas EJ, et al: Concomitant administration of GonaCon™ and rabies vaccine in female dogs (Canis familiaris) in Mexico. Vaccine 2013;31:4442–4447. doi: 10.1016/j.vaccine.2013.06.061

11.
Aponte PM, Gutierrez-Reinoso MA, Sanchez-Cepeda EG, et al: Active immunization against GnRH in pre-pubertal domestic mammals: testicular morphometry, histopathology and endocrine responses in rabbits, guinea pigs and ram lambs. Animal 2018;12:784–793. doi: 10.1017/S1751731117002129

12.
Liu Y, Tian Y, Zhao X, et al: Immunization of dogs with recombinant GnRH-1 suppresses the development of reproductive function. Theriogenology 2015;83:314–319. doi: 10.1016/j.theriogenology.2014.06.029

13.
Jiang S, Li Y, Liu Y, et al: Effect of active immunization against GnRH-I on the reproductive function in cats. Anim Sci J 2015;86:747–754. doi: 10.1111/asj.12355

14.
Chang AM, Chen CC, Lee JW, et al: Effects of a novel recombinant gonadotropin-releasing hormone-1 vaccine on the reproductive function of mixed-breed dogs. Vaccine 2023;41:2214–2223. doi: 10.1016/j.vaccine.2023.02.061

15.
Maffi S, Bonometti A, Chiaffredo C, et al: Assessment of body condition in long-distance sled dogs: validation of the body condition score and its association with ultrasonographic, plicometric, and anthropometric measurements. Vet Sci 2025;12:766. doi: 10.3390/vetsci12080766

16.
Altoé ALO: Efeito do imunocontraceptivo anti-GnRH na atividade ovariana de ratas Wistar [dissertation]. Vila Velha (ES); Universidade Vila Velha: 2025.

17.
Caffaratti M, González G, Gorla N, et al: Reproductive parameters of the Dogo Argentino bitch. J Vet Med 2013;2013:495975. doi: 10.1155/2013/495975

18.
Cardoso LR, Fontes D, Allison J, et al: Ovarian morphometrical evaluation to assess reproductive activity suppression in gilts immunized against GnRH. Res Vet Sci 2021;136:519–526. doi: 10.1016/j.rvsc.2021.04.005

19.
Constantin S, Bjelobaba I, Stojilkovic SS: Pituitary gonadotroph-specific patterns of gene expression and hormone secretion. Curr Opin Pharmacol 2022;66:102274. doi: 10.1016/j.coph.2022.102274

20.
de Gier J, Kooistra HS, Djajadiningrat-Laanen SC, et al: Differential regulation of LH and FSH secretion around the time of ovulation in the bitch. Theriogenology 2006;66:1419–1422. doi: 10.1016/j.theriogenology.2006.02.001

21.
Stornelli M, Praderio R, García M, et al: Serum progesterone concentration, volume, and apoptosis of corpora lutea in early, middle and late diestrus in the bitch. Anim Reprod Sci 2020:221:106591. doi: 10.1016/j.anireprosci.2020.106591

22.
Nett T, Akbar A, Phemister R, et al: Levels of luteinizing hormone, estradiol and progesterone in serum during the estrous cycle and pregnancy in the beagle bitch. Proc Soc Exp Biol Med 1975;148:134–139. doi: 10.3181/00379727-148-38491

23.
Gloria A, Contri A, Carluccio A, et al: Blood periovulatory progesterone quantification using different techniques in the dog. Anim Reprod Sci 2018;192:179–184. doi: 10.1016/j.anireprosci.2018.03.006

24.
Freitas LA, Vasconcelos FR, Moura AAAN, et al: Histomorphometry and uterine proteomics during the normal reproductive cycle in bitches. Res Soc Dev 2021;10:e18101119093. doi: 10.33448/rsd-v10i11.19093

25.
Barrau M, Abel J, Verhage H, et al: Development of the endometrium during the estrous cycle in the bitch. Am J Anat 1975;142:47–65. doi: 10.1002/aja.1001420105

26.
Chang A, Lin T, Yu J, et al: Effects of a recombinant gonadotropin-releasing hormone vaccine on reproductive function in adult male ICR mice. Vaccines (Basel) 2021;9:808. doi: 10.3390/vaccines9080808

27.
Siel D, Ubilla M, Vidal S: Reproductive and behavioral evaluation of a new immunocastration dog vaccine. Animals (Basel) 2020;10:226. doi: 10.3390/ani10020226

28.
Levy JK, Friary JA, Miller LA, et al: Long-term fertility control in female cats with GonaCon™, a GnRH immunocontraceptive. Theriogenology 2011;76:1517–1525. doi: 10.1016/j.theriogenology.2011.06.022