Evaluation of non-linear models for genetic parameters estimation of growth curve traits in Kermani sheep
- 59 Downloads
In the present study, 10,116 body weight-age records were measured on 2537 Kermani lambs. The records were collected from Kermani Sheep Breeding Station, located in Shahrbabak city, Kerman Province, south-eastern part of Iran, between 1993 and 2013 and used for evaluation of non-linear models describing growth curve from birth to yearling age and estimation of genetic parameters for growth curve traits in Kermani sheep. Six non-linear models including Brody, negative exponential, von Bertalanffy, Richards, Verhulst, and Gompertz were compared applying Akaike’s information criterion (AIC), root mean square error (RMSE) and Durbin-Watson statistic (DW) for determining the most appropriate model describing the growth curve in Kermani sheep. The von Bertalanffy model showed the lowest AIC and RMSE among the tested models. Furthermore, positive autocorrelations were found between residuals under the all tested model with the lowest value under the von Bertalanffy model. Therefore, von Bertalanffy model was selected as the best one for describing growth curve in Kermani sheep. A multivariate animal model was used for genetic analysis of the growth curve traits including parameters A (estimated mature weight), B (an integration constant related to initial animal weight), K (maturation rate), inflection age (IA), and inflection weight (IW) under a Bayesian approach. Posterior means for heritability estimates of A, B, K, IA, and IW were significant values of 0.10, 0.03, 0.04, 0.15, and 0.10, respectively. The parameter A had significant and positive genetic and phenotypic correlations with parameters B, IA, and IW. The posterior means for genetic and phenotypic correlations between parameters A and K were negative estimates of − 0.32 and − 0.22, respectively, implied that the lambs with slower maturation rate had higher mature weight. Positive and medium estimates were obtained for posterior means of phenotypic (0.31) and genetic (0.35) correlations between B and K. The posterior means for phenotypic and genetic correlations of B with IA and IW were not statistically significant. High and positive estimates were obtained for posterior means of genetic (0.6) and phenotypic (0.84) correlations between IA and IW. Generally, von Bertalanffy model showed high level of adequacy for describing the growth curve in Kermani sheep. Low additive genetic variations were found for all the studied growth curve traits. Therefore, the traits highly influenced by environmental which necessitate improving environmental influencing factors on the studied traits for achieving desired shape of growth curve and developing an efficient breeding strategy in Kermani sheep.
KeywordsGrowth pattern Non-linear functions Sheep Bayesian approach
The authors wish to thank all Breeding Station staff of Kermani sheep, especially Mr. M. Meimandi-Nia which involved in data collection and maintaining the flock through the years.
Compliance with ethical standards
All applicable international, national, and/or institutional guidelines for the care and use of animals were followed.
Conflict of interest
The authors certify that there are no conflicts of interests among authors and between authors and other people and organizations.
- Abegaz, S., van Wyk, J.B. and Olivier, J. J., 2010. Estimation of genetic and phenotypic parameters of growth curve and their relationship with early growth and productivity in Horro sheep. Archiv Tierzucht, 53, 85–94.Google Scholar
- Akbas, Y., Taskyn, T. and Demiroren, E. 1999. Comparison of several models to fit the growth curves of Kivircik and Daglic male lambs. Turkish Journal of Veterinary and Animal Science, 3, 537–544.Google Scholar
- Bahreini Behzadi, M. R., Aslaminejad, A. A., Sharifi, A.R. and Simianer, H., 2014. Comparison of mathematical models for describing the growth of Baluchi sheep. Journal of Agricultural Science and Technology, 16, 57–68.Google Scholar
- Ebangi, A.L., Nwakalor, L.N., Mbah, D.A. and Abba, D., 1996. Factors affecting the birth weight and neonatal mortality of Massa and Fulbe sheep breeds in a hot and dry environment, Cameroon. Revue Delevage et de Medecine Veterinaire Des Pays Tropicaux, 49, 349–353.Google Scholar
- Ghavi Hossein-Zadeh, N, 2015b. Bayesian estimates of genetic relationships between growth curve parameters in Shall sheep via Gibbs sampling. Iranian Journal of Applied Animal Science, 5, 897–904.Google Scholar
- Ghavi Hossein-Zadeh, N, 2017. Modelling growth curve in Moghani sheep: comparison of non-linear mixed growth models and estimation of genetic relationship between growth curve parameters. Journal of Agricultural Sciences, 155, 1150–1159.Google Scholar
- Gomez, D.A.A., Munoz, M.F.C. and Betancur, L.F.R., 2008. Modelacion de funciones de crecimiento aplicadas a la produccion animal. Revista Colombiana de Ciencias Pecuarias. 21, 39–58.Google Scholar
- Keskin, I., Dag, B., Sariyel, V. and Gokmen, M., 2010. Estimation of growth curve parameters in Konya Merino sheep. South African Journal of Animal Science, 39(2), 163–168.Google Scholar
- London, J.C. and Weniger, J.H., 1995. Investigations into traditionally managed Djallonke-sheep production in the humid and subhumid zones of Asante, Ghana. III. Relationship between birth weight, pre-weaning growth, and post-weaning growth of lambs. Journal of Animal Breeding and Genetics, 112, 431–453.CrossRefGoogle Scholar
- Mendez-Gomez, A.C., Lopez-Ordaz, R., Peralta-Laison, M., Ulloa-Arvizu, R., Pedraza- Villagomez, P., Ruiz-Lopez, J., Berruecos-Villalobos, J.M. and Vasquez-Pelaez, C.G., 2014. Estimación de heredabilidad de la curva de crecimiento en el borrego de raza Chiapas en México. Animal Gentic Resources, 54, 85–91.CrossRefGoogle Scholar
- Mirderikvandi, M., Masoudi, A., Khaldari, M., Bojarpour, M. and Nazari, P., 2016. The effect of some factors on growth performance of Lori Bakhtiari lambs. Livestock Research for Rural Development, 28, 12.Google Scholar
- Misztal, I., Tsuruta, S., Strabel, T., Auvray, B., Druet, T. and Lee, D., 2002. BLUPF90 and related programs (BGF90). In: Proceedings of the 7th World Congress on Genetics Applied to Livestock Production, (Montpellier, France).Google Scholar
- Sefidbakht, N., 2011. Future aspect of sustainable animal production in Iran focusing on the sheep and goat. In: Proceedings of the 1st seminar on animal production in tropical environment, (Shahid Bahonar Kerman University and Iranian Society of Animal Science), Iran, 1–9.Google Scholar
- Statistical Analysis System (SAS), 2004. SAS users’ guide, version 9. 1. SAS Institute Inc., Cary, North Carolina, USA.Google Scholar
- Tariq, M.M., Bajwa, M.A., Waheed, A., Eyduran, E., Abbas, F., Bokhari, F.A. and Akbar, A., 2011. Growth curve in Mengali sheep breed of Balochestan. The Journal of Animal and Plant Sciences, 24 (1), 5–7.Google Scholar
- Waheed, A., Khan, M.S., Ali, S. and Sarwar, M., 2011. Estimation of growth curve parameters in Beetal goats. Archiv Tierzucht, 54, 287–296.Google Scholar