Skip to main content Skip to main navigation menu Skip to site footer
Articles
Published: 2024-12-31

A paradox of the ovulatory patterns in the living laboratory, African giant pouched rat (Cricetomys gambianus) from Tanzania

Department of Veterinary Anatomy and Pathology, Sokoine University of Agriculture, P.O.BOX 3000, Morogoro, Tanzania
Cricetomys, Creatinine, Progesterone, Ovulation, Copulation, Penile Epidermal Spines, Tanzania

Abstract

The African giant pouched rat (Cricetomys gambianus) has emerged as a valuable model animal deployed in biomedical and other researches with humanitarian application due to its intelligence, socio-behavior, and adaptability to captivity. This rodent lives in solitary and belongs to the family Cricetidae that synchronises sexual behavioral onset with subsequent maturation of their gonads and gametes just prior to the beginning of the short rains of Tanzania. The current study set out to investigate whether ovulation in this species is induced or spontaneous. The study involved five sexually mature intact tame females and five sexually matured vasectomized wild males. Females were monitored non-invasively for ovarian cyclicity by measuring urinary progesterone every 2 days over 84days. Females were subjected to three separate step-wise experiments with different treatments as follows: step one was singly housed, which served as the control (C), followed by Non-Physical Contact with a vasectomized male (NPC) and Physical Contact with the same vasectomized male (PC), respectively. The average urinary progesterone concentration was similar in all three treatments, with a urinary progesterone spike indicating ovulation occurring in all treatments, suggesting a spontaneous ovulating strategy. However, upon assessment of the male penis, it was revealed that part of the glans penis had small epidermal spines which somehow resembles to those reported in induced ovulators. The findings from this study on the African giant pouched rat leaves a paradox as profiles of progesterone from females strongly suggest a spontaneous pattern of ovulation although the penile morphology of males have features suggesting induced pattern of ovulation. 



Downloads

Download data is not yet available.

References

  1. Goodman RL, Bittman EL, Foster DL, Karsch FJ. The endocrine basis of the synergistic suppression of luteinizing hormone by estradiol and progesterone. J Endocrinol. 1981;109(5):1414-7. https://doi.org/10.1210/endo-109-5-1414
  2. Espey L, Lipner H. Ovulation. In: Knobil E, Neill JD, editors. Physiology of Reproduction. New York: Raven Press; 1994.
  3. Milligan SR. Social environment and ovulation in the vole, Microtus agrestis. Reproduction. 1974;41:35-47. http://dx.doi.org/10.1530/jrf.0.0410035
  4. Milligan SR. Mating, ovulation and corpus luteum function in the vole, Microtus agrestis. Reproduction. 1975;42:35-44. https://doi.org/10.1530/jrf.0.0420035
  5. Bibeau CE, Stuart AT, Anthony ELP, Carroll RS, Baum MJ, King JC. Vaginocervical stimulation of ferrets induces release of luteinizing hormone-releasing hormone. J Neuroendocrinol. 1991;3(1):29-36. https://doi.org/10.1111/j.1365-2826.1991.tb00235.x
  6. Ramirez VD, Soufi WL. The neuroendocrine control of the rabbit ovarian cycle. J Physiol Reprod. 1994;2:585-611.
  7. Fernandez-Baca S, Madden DHL, Novoa C. Effect of different mating stimuli on induction of ovulation in the alpaca. Reproduction. 1970;22(2):261-7. https://doi.org/10.1530/JRF.0.0220261
  8. Parag A, Bennett NC, Faulkes CG, Bateman PW. Penile morphology of African mole rats (Bathyergidae): structural modification in relation to mode of ovulation and degree of sociality. J Zool. 2006;270(3):323-9. http://dx.doi.org/10.1111/j.1469-7998.2006.00141.x
  9. Hart DW, Medger K, Van Jaarsveld B, Bennett NC. Is the Mahali mole-rat (Cryptomys hottentotus mahali) a spontaneous or induced ovulator? Can J Zool. 2020;98(4):299-305. https://doi.org/10.1139/cjz-2019-0112
  10. Jöchle W. Current research in coitus-induced ovulation: a review. J Reprod Fertil Suppl. 1975;165-207. PMID: 810583
  11. Viker SD, Larson RL, Kiracofe GH, Stewart RE, Stevenson JS. Prolonged postpartum anovulation in mastectomized cows requires tactile stimulation by the calf. J Anim Sci. 1993;71(4):999-1003. http://dx.doi.org/10.2527/1993.714999x
  12. de Bruin PR, Ganswindt A, Bennett NC, Medger K. The pattern of ovulation in the southern African spiny mouse (Acomys spinosissimus). Mamm Biol. 2014;79(5):318-24. https://doi.org/10.1016/j.mambio.2014.05.003
  13. Dewsbury DA, Hodges AW. Copulatory behavior and related phenomena in spiny mice (Acomys cahirinus) and hopping mice (Notomys alexis). J Mammal. 1987;68(1):49-57. https://doi.org/10.2307/1381044
  14. Cort S, Locatelli F, Papadimitriou D, Donadoni C, Del Bo R, Crimi M, et al. HMG Advance Access published December 8, 2005. https://doi.org/10.1093/hmg/ddi446
  15. Orr TJ, Brennan PLR. All features great and small—the potential roles of the baculum and penile spines in mammals. Integr Comp Biol. 2016;56(4):635-43. http://dx.doi.org/10.1093/icb/icw057
  16. Skinner JD, Chimimba CT. The mammals of the southern African sub-region. Cambridge (United Kingdom): Cambridge University Press; 2005. https://doi.org/10.1017/CBO9781107340992
  17. Ngalameno MK, Luziga C, Hart DW, Bennett NC. The pattern of reproduction in the African giant pouched rat, Cricetomys gambianus from Tanzania: unravelling the environmental triggers for breeding. Can J Zool. 2024;102(6):545-55. http://dx.doi.org/10.1139/cjz-2023-0205
  18. Ajayi SS. Field observations on the African giant rat Cricetomys gambianus Waterhouse in southern Nigeria. Afr J Ecol. 1977;15(3):191-8. https://doi.org/10.1111/j.1365-2028.1977.tb00397.x
  19. Malekani M, Westlin LM, Paulus JJ, Potgieter HC. Oestrous occurrence in captive female Cricetomys gambianus (Rodentia: Cricetidae). J Zool. 2002;257(3):295-301. http://dx.doi.org/10.1017/S0952836902000894
  20. Akinloye AK, Oke BQ. Sex hormonal pattern of the female African giant rat (Cricetomys gambianus, Waterhouse) at different stages of the oestrous cycle. Niger Vet J. 2012;33.
  21. Ngalameno MK, Luziga C. Uncovering the identity of the living laboratory: a combined approach of COI gene sequencing and phylogenetic analysis of the African giant pouched rats. Tanz Vet J. 2022;37(2):22-9.
  22. Tamura K, Peterson D, Peterson N, Stecher G, Nei M, Kumar S. MEGA5: molecular evolutionary genetics analysis using maximum likelihood, evolutionary distance, and maximum parsimony methods. Mol Biol Evol. 2011;28(10):2731-9. https://doi.org/10.1093/molbev/msr121
  23. Folin O, Morris JL. On the determination of creatinine and creatine in urine. J Biol Chem. 1914;17:469-73. https://doi.org/10.1016/S0021-9258(18)88386-7
  24. Wolf TE, Arif A, Bennett NC, Ganswindt A. Noninvasive measurements of ovarian activity in Beira antelope (Dorcatragus megalotis). Reprod Domest Anim. 2019;54(2):275-9. https://doi.org/10.1111/rda.13351
  25. Larivière S, Ferguson SH. Evolution of induced ovulation in North American carnivores. J Mammal. 2003;84(3):937-47. https://doi.org/10.1644/BME-003
  26. Ali MN, Onyeanusi BI, Ayo JO, Ojo SA, Salami SO, Nzalak JO, et al. Effect of season on the reproductive organs of the female African giant rat (Cricetomys gambianus) in Zaria, Nigeria. Int J Morphol. 2011;29(3):841-4. http://dx.doi.org/10.4067/S0717-95022011000300029
  27. Webb EK, Saccardo CC, Poling A, Cox C, Fast CD. Rapidly training African giant pouched rats (Cricetomys ansorgei) with multiple targets for scent detection. Behav Process. 2020;174:104085. https://doi.org/10.1016/j.beproc.2020.104085
  28. Reither K, Jugheli L, Glass TR, Sasamalo M, Mhimbira FA, et al. Evaluation of Giant African Pouched Rats for Detection of Pulmonary Tuberculosis in Patients from a High-Endemic Setting. PLoS One. 2015;10(10):e0135877. https://doi.org/10.1371/journal.pone.0135877


How to Cite

1.
Ngalameno M. A paradox of the ovulatory patterns in the living laboratory, African giant pouched rat (Cricetomys gambianus) from Tanzania. J Ideas Health [Internet]. 2024 Dec. 31 [cited 2025 Feb. 17];7(6):1221-6. Available from: https://jidhealth.com/index.php/jidhealth/article/view/394