Original scientific paper
Genetic Evaluation of Litter Size Traits in Pannon White Rabbits
Nguyen Thao Nguyen
; University of Kaposvár, 40 Guba S. str., H-7400 Kaposvár, Hungary
János Farkas
; University of Kaposvár, 40 Guba S. str., H-7400 Kaposvár, Hungary
Zsolt Szendrő
; University of Kaposvár, 40 Guba S. str., H-7400 Kaposvár, Hungary
István Nagy
; University of Kaposvár, 40 Guba S. str., H-7400 Kaposvár, Hungary
Abstract
In this study 21060 kindling records (collected between 1992 and 2016) of 4926 Pannon White (PW) does inseminated with 1414 PW mating bucks were analysed. Genetic components and genetic trends for the number of kits born alive (NBA), number of kits born dead (NBD) and the total number of born kits (TNB) were estimated using the four single trait animal models. Heritability estimates were low for all traits. For NBA and TNB they ranged between 0.06-0.07±0.01. For NBD they were close to zero (0.019-0.020±0.004). Th e ratios of the permanent environmental to the phenotypic variances ranged between 0.07-0.1±0.01 for NBA, 0.009-0.013 ±0.004 for NBD and 0.07-0.10±0.01 for TNB. Analysing the models’ fi t showed that bias values were practically zero for all traits and models. After selecting the best fitted model (containing parity, age of the doe and year-month of kindling) it was extended with dominance effects. As a result, heritability estimates decreased to 0.06±0.01 for NBA, 0.02±0.01 for NBD and 0.06±0.01 for TNB. Th e ratio of the permanent environmental effects to the phenotypic variances also decreased to 0.08±0.01 for NBA, 0.008±0.005 for NBD and 0.08±0.001 for TNB. Ratios of the dominance effects were larger than those of the heritability estimates for NBA (0.09±0.01) and TNB (0.08± 0.01). On the contrary for NBD ratio of the dominance effects was smaller than the heritability estimates (0.01±0.002). Confounding was found among additive genetic, permanent environmental and dominance effects. Inclusion of dominance effects also reduced genetics trends (0.027 vs 0.026, 0.0003 vs -0.0004 and 0.0258 vs 0.0255 for NBA, NBD and TNB, respectively). Spearman rank correlation coefficients between breeding values of the additive and dominance models were high for all traits (0.99). However, some re-ranking was observed among the top ranked animals for all litter size traits.
Keywords
rabbit; litter traits; dominance effects; genetic trends
Hrčak ID:
188112
URI
Publication date:
16.10.2017.
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