Analysis of the influence of genetic and non-genetic factors on the birth weight and weaning weight of lambs

Keywords: birth and weaning weight of lambs; ram genotype; year of lambing; age of the ewes; litter size (type of birth); sex of lamb; sex ratio in twins; the Ascanian fine-fleece breed.


The main aim of this paper is to analyze the influence of genetic and non-genetic factors on the birth weight and weaning weight of lambs. The study was carried out on the basis of the Institute of Animal Husbandry of Steppe Regions named by M. F. Ivanov “Askania-Nova” – the National Scientific Agricultural Center in Sheep Breeding of NAAS. Birth and weaning weights data collected during a 5-vear period from 3961 lambs were used. The reproductive traits of the Ascanian fine-fleece (AC) ewes were evaluated in combination with the rams of different genotypes: Ascanian fine-fleece, Australian merino (AM) and half-bred animals (1/2AC+1/2AM). The main effect of the ram genotype and the year of lambing, the age of the ewes, the litter size, the sex of lamb and the sex ratio in twins on the birth weight and weaning weight of lambs was analysed using one-way ANOVA. Differences between years of the 5-year period were highly significantly (P < 0.001) for all lamb traits studied. The effects of the environmental factor (year of lambing) on the birth weight and weaning weight of lambs represented 27.2 and 15.2 per cent of the total variance, respectively. The ram-group effects, which are mainly genetic differences, were highly significant (P < 0.001) in all traits. Age of dam had significant effect on the birth weight of lambs (P = 0.048) and was relatively unimportant as a source of variation. Two-year-old ewes bore lighter lambs than older ewes. There were no significant differences in the weaning weight of lambs from the ewes of different age classes. Survival rate was related to birth weight of lambs. Lamb survival increased up to a birth weight of 4.0 kg and only declined when they weighed more than 5.0 kg at birth. Our results showed that singles were 0.61 kg heavier than twins at birth and were 2.42 kg heavier than twins at weaning. Litter size (type of birth) was responsible for 42.5 and 10.0 % of total variability in birth and weaning weights of lambs, respectively (in both cases: P < 0.001). Average birth and weaning weights of male lambs were higher than the females (in both cases: P < 0.001).


Babar, M. E., & Javed, K. (2009). Non-genetic factors affecting reproductive traits in Lohi sheep. Acta Agri-culturae Scandinavica, Section A – Animal Science, 59(1), 48–52. doi: 10.1080/09064700802650035.

Besedin, O. (2011). Features of reproductive ability of ewes of Taurian type of Ascanian Merino breed. Pre-mountain and Mountain Agriculture and Stock-breeding, 53(І), 108–112 (in Ukrainian).

Blackwell, R. L., & Henderson, C. R. (1955). Variation in fleece weight, weaning weight and birth weight of sheep under farm conditions. Journal of Animal Sci-ence, 14(3), 831–843. doi: 10.2527/1955.143831x.

Burfening, P. J., & Kress, D. D. (1993). Direct and mater-nal effects on birth and weaning weight in sheep. Small Ruminant Research, 10(2), 153–163. doi: 10.1016/0921-4488(93)90058-P.

Caro-Petrović, V., Petrović, M. P., Ilić, Z., Petrović, M. M., Milošević, B., Ružić-Muslić, D., & Maksimović, N. (2013). Effect of genotype, sire, sex, gestation length on birth weight of lambs. Biotechnology in Animal Husbandry, 29(4), 685–693. doi: 10.2298/BAH1304685C.

DeBaca, R. C., Bogart, R., Calvin, L. D., & Nelson, O. M. (1956). Factors affecting weaning weights of cross-bred spring lambs. Journal of Animal Science, 15(3), 667–678. doi: 10.2527/jas1956.153667x.

Eltawil, E. A., Hazel, L. N., Sidwell, G. M., & Terrill, C. E. (1970). Evaluation of environmental factors affecting birth, weaning and yearling traits in Navajo sheep. Journal of Animal Science, 31(5), 823–827. doi: 10.2527/jas1970.315823x.

Hammer, Ø., Harper, D. A., & Ryan, P. D. (2001). PAST: Paleontological Statistics Software Package for Edu-cation and Data Analysis. Palaeontologia Electronica, 4, 1–9.

Hight, G. K., & Jury, K. E. (1970). Hill country sheep pro-duction: II. Lamb mortality and birth weights in Romney and Border Leicester × Romney flocks. New Zealand Journal of Agricultural Research, 13(4), 735–752. doi: 10.1080/00288233.1970.10430507.

Kramarenko, S. S., Lugovy, S. I., Lykhach, A. V. & Kra-marenko, O. S. (2019). Analysis of biometric data in animal breeding and selection. Mykolayiv, MNAU. 211 (in Ukrainian).

Mavrogenis, A. P. (1982). Environmental and genetic factors influencing milk production and lamb output of Chios sheep. Livestock Production Science, 8(6), 519–527. doi: 10.1016/0301-6226(82)90029-X.

Nezhlukchenko, Т. І., & Oboista, Т. V. (2013). Intrabreed features of the reproductive capacity of Askanian fi-ne-fleece sheep. Taurida Scientific Herald. Series: Ru-ral Sciences, 83, 188–191 (in Ukrainian).

Petrović, M. P., Caro Petrović, V., Ružić-Muslić, D., Maksimović, N., Petrović, M. M., Ilić, Z. Z., & Stojković, J. (2015). Effect of genetic and environ-mental factors on the phenotype characteristics of lambs. Biotechnology in Animal Husbandry, 31(2), 223–233. doi: 10.2298/BAH1502223P.

Pokhyl, V. I., & Mykolaychuk, L. P. (2019). Age-related variability of the woollen coat of Romanivska sheep breed. Theoretical and Applied Veterinary Medicine, 7(3), 172–176. doi: 10.32819/2019.71031 (in Ukrain-ian).

Pokhyl, V. I., & Mykolajchuk, L. P. (2020). Meat produc-tivity of young sheep animals of different origin. The-oretical and Applied Veterinary Medicine, 8(1), 26–30. doi: 10.32819/2020.81005 (in Ukrainian).

Pokhyl, V. I., Mykolajchuk, L. P., & Izhboldina, O. O. (2020). Features of sheepskin productivity of different origin sheep. Theoretical and Applied Veterinary Med-icine, 8(2), 128–131. doi: 10.32819/2020.82017 (in Ukrainian).

Sánchez-Dávila, F., Bernal-Barragán, H., Padilla-Rivas, G., del Bosque-González, A. S., Vázquez-Armijo, J. F., & Ledezma-Torres, R. A. (2015). Environmental fac-tors and ram influence litter size, birth, and weaning weight in Saint Croix hair sheep under semi-arid con-ditions in Mexico. Tropical Animal Health and Pro-duction, 47(5), 825–831. doi: 10.1007/s11250-015-0795-6.

Sidwell, G. M., & Grandstaff, J. O. (1949). Size of lambs at weaning as a permanent characteristic of Navajo ewes. Journal of Animal Science, 8(3), 373–380. doi: 10.2527/jas1949.83373x.

Vdovychenko, Yu., & Zharuk, P. (2019). Genetic re-sources of sheep in Ukraine. Bulletin of Agricultural Science, 97(5), 38–44. doi: 10.31073/agrovisnyk201905-04 (in Ukrainian).

Vesely, J. A., & Peters, H. F. (1964). The effects of breed and certain environmental factors on birth and wean-ing traits of range sheep. Canadian Journal of Animal Science, 44(2), 215–219. doi: 10.4141/cjas64-033.

Vesely, J. A., & Slen, S. B. (1961). Heritabilities of wean-ing weight, yearling weight, and clean fleece weight in range romnelet sheep. Canadian Journal of Animal Science, 41(1), 109–114. doi: 10.4141/cjas61-014.

Voitenko, S. L., Porkhun, M. G., Sydorenko, O. V., & Ilnytska, T. Y. (2019). Genetic resources of agricultur-al animals of Ukraine at the beginning of the third mil-lennium. Animal Breeding and Genetics, 58, 110–119. doi: 10.31073/abg.58.15 (in Ukrainian).

Vovchenko, B. O., & Klyuyenkov, V. O. (2012). The evaluation of breeding and productive characters of ewes of the Dnipropetrovs’k type of Askanian mutton and wool sheep. Taurida Scientific Herald. Series: Ru-ral Sciences, 78, 2(1), 38–41 (in Ukrainian).

Yilmaz, O., Denk, H., & Bayram, D. (2007). Effects of lambing season, sex and birth type on growth perfor-mance in Norduz lambs. Small Ruminant Research, 68(3), 336–339. doi: 10.1016/j.smallrumres.2005.11.013.

Zaruba, K. V., Drozd, S. L., & Gladii, I. A. (2019). The results of crossbreeding the rams-sires foreign breeding with the ewes of the Ascanian fine-fleeced breed. Sheep and Goat Breeding, 4, 34–42. doi: 10.33694/2415-3958-2019-1-4-34-42 (in Ukrain-ian).

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Kramarenko, A., Kramarenko, S., Lugovoy, S., & Yulevich, O. (2020). Analysis of the influence of genetic and non-genetic factors on the birth weight and weaning weight of lambs. Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies. Series: Agricultural Sciences, 22(93), 14-21.

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