Multidirectional sexual dimorphism for the live weight in domestic pigs

In mammals, males are typically larger and heavier than females. In particular, the average weight of wild boar females is about 80% of that of the males. In a vast majority of domestic swine populations (breeds, populations of breeding groups), this value varies from 70 to 91% (the central value of the range of variation of 81%). However, there are three genealogically continuous groups of domestic pigs (Vietnamese Masked breed MY, minisibs and Svetlogorsk mini-pigs) that make exceptions. Their specific feature is the reverse sexual dimorphism in weight – mature females are heavier than males. This phenomenon, not typical of the species Sus scrofa, was the reason for the present study. Although this research is preliminary, some assumptions can be made. Firstly, the ratio of the weight of mature females to the weight of mature males is obviously characteristic of the species, deviations from which repressed stabilizing selection. Second, in domestic pigs, normal and reverse sexual dimorphism in weight may be different in nature: in the former case, it is a great length of the period of intensive growth in males, in the latter, a large growth rate of females during the first year of life. The third characteristic of domestic pigs in Southeast Asia, early puberty, may be due to a consistent use of young and therefore small-sized males for reproduction purposes; however, the small size due to their youth, cannot be a target of artificial selection – nor can they be the cause of reverse sexual dimorphism in weight. Finally, reverse sexual dimorphism may be due to a tendency towards early obesity in females, which might be to a single mutation as its genetic cause.

male, female, live weight, sexual dimorphism

1. Иванчук В.А. Биогенетические особенности редких и исчезающих пород свиней. Ветеринария сельскохозяйственных животных. 2011;2:55-60.

2. Кабанов В.Д. Повышение продуктивности свиней. М.: Колос, 1983.

3. Кабанов В.Д., Терентьева А.С. Породы свиней. М.: Агропромиздат, 1985.

4. Капанадзе Г.Д. Биологические и зоотехнические особенности светлогорских мини-свиней, их совершенствование и рациональное использование: Автореф. дис. … д-ра биол. наук. М.: Российский гос. аграрный ун-т – МСХА им. К.А.Тимирязева, 2011.

5. Князев С.П., Шатохин К.С., Гончаренко Г.М., Фролова В.И., Запорожец В.И., Ермолаев В.И., Никитин С.В. Динамика роста живой массы у мелкой и крупной форм домашней свиньи. Научное обозрение. 2015;6:9-13.

6. Козло П.Г. Изменчивость веса тела дикого кабана, обитающего в Беловежской Пуще. Березинский заповедник. Исследования. Вып. 3. Минск: Урожай, 1974.

7. Лакин Г.Ф. Биометрия. М.: Высш. шк., 1973.

8. Никитин С.В., Князев С.П. Отбор и адаптация в популяциях домашних свиней. Saarbrucken: Lambert Academy Publishing (LAT), 2015.

9. Порядок и условия проведения бонитировки племенных свиней. Департамент животноводства и племенного дела России. М., 2009.

10. Разведение и болезни свиней. Ч. I: (в двух частях). Под общ. ред. А.И. Ятусевича. Витебск: ВГАВМ, 2013.

11. Тихонов В.Н. Лабораторные мини-свиньи: генетика и медико-биологическое использование. Новосибирск: ИЦиГ СО РАН, 2010.

12. Bollen P.J.A., Madsen L.W., Meyer O. Ritskes-Hoitinga J. Growth differences of male and female Göttingen minipigs during ad libitum feeding: a pilot study. Lab. Anim. 2005;39:80-93.

13. Haqq C.M., Donahoe P.K. Regulation of sexual dimorphism in mammals. Physiol. Rev. 1998;78(1):33.

14. Moretti M. Biometric data and growth rates of mountain population of wild boar (Sus scrofa L.), Ticino, Switzerland. J. Mountain Ecol. 1995;3:56-59.

15. Rothschild M.F., Zhi-liang H., Zhihua J. Advances in QTL mapping in pigs. Intern. J. Biol. Sci. 2007;3:192-197.

16. Simianer H., Köhn F. Genetic management of the Göttingen Minipig population. J. Pharmacol. Toxicol. Meth. 2010;62:221-226.

17. Simon F.R. Hormonal regulation of bile secretion. The Liver: Biology and Pathobiology. 5th еd., 2009.

18. Vieites C.M., Basso C.P. Bartoloni N. Wild boar (Sus scrofa ferus): productivity index in an experimental outdoor farm. In. Vet. 2003;5(1):91-95.