Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 31106
On the Influence of Certain Natural Factors on the Sperm Quality and Sexual Behaviour of Rams

Authors: Pascal Constantin, Gîlcă Ioan, Radu Rusu Răzvan, Nacu Gherasim


In the Northern hemisphere, sheep reproduction is seasonal (September-November). Among several natural factors influencing the reproduction status of rams, we studied the daylight length and temperature. Rams from different breeds were studied: Merinos de Palas (half-precocious), Karakul de Botosani (halfbelated) and Turcana (belated breed, low reproductive plasticity). In Merinos de Palas, ejaculate volume during sexual repose is 51.3% from normal quantity. When autumn climate was experimentally induced, ejaculate volume reached 98.45% (Merinos), 94.97% (Karakul) and 97.59% (Turcana). Semen density increased from 1.031-1.033 till 1.035 after exposition to artificial light and temperature conditions. Spermatozoids mobility and sperm pH improved, passing over 82% and 6.75, values identical to those in the natural reproduction season. Behaviour analysis after photoperiodicity indicated that over 83.3% Merinos and Karakul males and all Turcana rams exteriorised normal and intense sexual reflexes. Certain effort and reduced expenses brought rams in good condition, producing higher quantity and quality sperm.

Keywords: sexual behaviour, natural factors, photoperiodicity, Romanian sheep

Digital Object Identifier (DOI):

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1351


[1] H. Andersson, JD. Johnston, S. Messager, D.G. Hazlerigg. 2005. Photoperiod regulates clock gene rhythms in the ovine liver. General and Comparative Endocrinology 142. 357-363. Scotland, UK.
[2] AG. Andersen, TK Jensen, E Carlsen, N J├©rgensen, AM Andersson, T Krarup, N Keiding and NE Skakkeb├ªk. 2000. High frequency of suboptimal semen quality in an unselected population of young men. Human Reproduction 15(2): 366-372.
[3] D.T. Barid, Mac Nelly A.S. 1981. Gonadotripic control of follicular development and function during the oestrus cycle of the ewe. J. Reprod. Fert. Suppl. 30.
[4] T. Bonadonna. 1956. On some biological and non biological factors that may effect the collection and quality of the semen. Congr. Animal Reproduction (Camb.). p 105-112.
[5] L.P. Cahill, P. Mauleon. 1980. Season and photoperiod effects on follicles and atresia in the sheep ovary. Aust. J. Biol. Sci. 37.
[6] I. G├«lcâ, C. Pascal, Mihaela Ivancia, S. Creangâ, B. Pâsârin. 2008. Comparation of milk yeld and reproductive indices between the Romanian sheep breeds. 12th Annual Conference of the European Society for Domestic Animal Reproduction. Book of abstract, ISSN 0936-678. p 97.
[7] N. Luca et al. 1971. Reproduction in Domestic Animals. Edit. Agro- Silvica, Bucharest - Romania.
[8] T. Mann. 1960. Evolution of sperm by chemical analysis. The artificial insemination of farm animal. E.J. Perry (edit) New Brunswick N.J. Rutgers, University, Press.
[9] D. Nadolu, A.H. Anghel. 2007. The influence of the photo-periodic variations upon the rams sexual activity. Lucrari Stiintifice, Seria Zootehnie, Usamv Iasi-Romania, pp 277-280.
[10] C. Pascal, Mihaela Ivancia, I. G├«lcâ, Gh. Nacu, L. Stancescu, Gh. Hrincâ, N. Iftimie. 2009. Study about some factors which have influence about reproduction function in sheep. Lucrari Stiintifice, Seria Zootehnie USAMV Iasi-Romania, p 467-475.
[11] C. Pascal, Mihaela Ivancia, Gh. Nacu. 2008. The influence of some factors on the reproductive function of Romanian local sheep. 12th Annual Conference of the European Society for Domestic Animal Reproduction. Book of abstract, ISSN 0936-678. p 99.
[12] C. Pascal, L. Stancescu, S. Bosanciuc. 2005. The of Merinos de Palas precocious utilisation in reproduction young ewes. The 4th International Syposium "Prospects for the 3 th Millennium Agriculture", vol. 61. p. 104 - 109, Seria Zootehnie şi Biotehnologii, USAMV Cluj-Napoca, ISSN 1454-2390.
[13] A. Perkins, et. al. 1992. J. Anim. Sci. 70: 2722-2725.
[14] E. O. Price, et. al. 1992. J. Anim. Sci. 70: 3376-3380.
[15] C.J. Thwaites. 1982. Development of mating behaviour in the prepubertal ram, Anim. Behav. 30, pp. 1053-1059.
[16] Zarazaga L.A., Malpaux B., Chemineau Ph. 1997. The characteristics of the melatonin secretory rhythm are not modified by the stage of pregnancy in ewes. Reproduction, Nutrition, Development 37, p. 105- 112.