Establishment of the gender of rabbits by craniometric and morphological features of the skull

Introduction. Sexual dimorphism in rabbits is poorly expressed, which creates a number of difficulties in determining the sex of the animal. The need to determine sex arises during forensic veterinary examination, archaeological and special morphological studies, as well as in the study of age and breed variability of animals using craniological material. This issue is especially relevant for veterinary and sanitary examination, since the sex of the animal can affect the quality of wool or the taste of meat, which affects the quality of the products obtained.
Objects and methods. The objects of the study were skulls (n = 4) of Californian breed ofrabbits and skulls (n = 4) of Soviet chinchilla breed. The stages of the study were: the creation of 8 bone preparations by boiling them in water with the addition of bicarbonate of soda, bleaching in a 3% hydrogen peroxide solution, comparison and morphometry.
Results. Based on the study, it is possible to identify craniological features characteristic of male and female rabbits: the angle of the lower jaw in males is thicker and more massive, has a more pronounced masticatory fossa; supraorbital processes of male rabbits are more branched and wide; the zygomatic process of the zygomatic bone has a thin elongated shape in females, and a wide oval in males; on the horizontal plate of the palatine bone of femalerabbits there is large number of holes; in males, the lattice opening resembles a cello in shape, and the pituitary gland resembles an oval; the occipito-sphenoid fusion in male rabbits is convex, and the occipital crest has a thickening. Thanks to the use of several breeds of rabbits in the experiment, it can be proved that these patterns relate to sex, and not to breed. The results of the study can be used to determine the sex of an animal by the skull or its fragments, which is important for forensic veterinary examination when using a craniological method for determining the sex of various animal species.

1. Kholamov A.I. Establishing the sex of the human skull according to the main craniometric parameters / A.I. Kholamov // Medicine: challenges of today: materials of the I International Scientific Conference — Chelyabinsk: Two Komsomol members. 2012. PP. 94-99. (in Russian).

2. Solovyov K.V. Comparison of the effectiveness of domestic methods for determining sex by the skull of an adult / K.V. Solovyov, A.E. Magdich, M.P. Kirillova // Proceedings of the Russian Military Medical Academy. 2021. Vol. 40. No. S1-3. pp. 304-308. (in Russian).

3. Bylinskaya D.S. / The facial skull of a river beaver (Castor fiber) / D.S.Bylinskaya, M.V. Shchipakin, A.V. Prutsakov, S.V. Virunen, S.A. Kuga // Hippology and veterinary medicine. — 2015. — No. 3 (17). — pp. 30-34. (in Russian).

4. Bylinskaya D.S. Anatomy of the maxillary bone of the Eurasian lynx / D.S. Bylinskaya, M.V. Shchipakin, N.V. Zelenevsky, D.V. Vasiliev // Agrarian education and science — in the development of animal husbandry. Materials of the International scientific and Practical Conference dedicated to the 70th anniversary of the Honored Worker of Agriculture of the Russian Federation, Honorary Worker of the Higher Educational Institution of the Russian Federation, laureate of the State Prize of UR, Rector of the Izhevsk State Agricultural Academy, Doctor of Agricultural Sciences, Professor Alexander Ivanovich Lyubimov. In 2 volumes. — Izhevsk. Izhevsk State Agricultural Academy. 2020. — pp. 260-262. (in Russian).

5. Virunen S.V. Morphological features of the structure of the skull of the river otter (Lutra Lutra) / S.V. Virunen, M.V. Shchipakin, N.V. Zelenevsky, D.S. Bylinskaya, A.V. Prusakov, D.V. Vasiliev // Hippology and veterinary medicine. — 2017. — № 2 (24). — Pp. 30-33. (in Russian).

6. Ziruk I.V. Specific features of the morphology of the skeleton of chinchilla and rat / I.V. Ziruk, A.V. Egunova, M.E. Kopchekchi, Ya.E. Yarosh // In the collection: Collection of scientific papers of the 11th International Interuniversity Conference on Clinical Veterinary Medicine in the format Purina Partners. 2021. pp. 485-489. (in Russian).

7. Popesco P. Atlas of Pet Anatomy. Volume 1. Head and neck. / P. Popesco // Publishing house "Nature". 1974. Reprint (reprint) HER Media Publishing House. 2012. Vol. 1. p. 188. (in Russian).

8. Nozdrachev A.D. Anatomy of a rabbit. / A.D. Nozdrachev, E.L. Polyakov, A.N. Fedin // Publishing House of St. Petersburg State University. 2009. p. 356. (in Russian).

9. Petrosyan E.V. Studying the morphology of hare and rabbit skull bones, their comparison / E.V. Petrosyan, V.V. Salautin, M.E. Kopchekchi, I.V. Ziruk // In the collection: Youth science — the development of the agro-industrial complex. Materials of the AllRussian (national) scientific and practical conference of students, postgraduates and young scientists. 2020. pp. 453-457. (in Russian).

10. Prusakov A.V. A method of making anatomical copies of bones by casting in a silicone mold / Prusakov A.V., Zelenevsky N.V., Shchipakin M.V., Shavrov S.S., Barteneva Yu.Yu., Bylinskaya D.S., Vasiliev D. V., Khvatov V.A., Stratonov A.S. // Patent for invention RU 2716677 C1, 03/13/2020. Application No. 2018142728 dated 12/03/2018. (in Russian).

11. Hasanov A.B. Gender differences in the ratios of some craniometric signs / A.B. Hasanov, A.Sh. Ibragimov, Z.M. Kerimov, I.N. Chairkin, N.L. Shepetovskaya, E.V. Kondyurova // News of higher educational institutions. Volga region. Medical sciences. 2020. No. 2 (54). pp. 51-61. (in Russian).