Selection responses for�the�number of�fertile eggs of�the�Brown Tsaiya duck (Anas platyrhynchos) after�a�single artificial insemination with�pooled Muscovy (Cairina moschata) semen

Abstract

-A seven-generation selection experiment comprising a selected (S) and a control (C) line was conducted with the objective of increasing the number of fertile eggs (F) of the Brown Tsaiya duck after a single artificial insemination (AI) with pooled Muscovy semen. Both lines consisted of about 20 males and 60 females since parents in each generation and each female duck was tested 3 times, at 26, 29 and 32 weeks of age. The fertile eggs were measured by candling at day 7 of incubation. The selection criterion in the S line was the BLUP animal model value for F. On average, 24.7% of the females and 15% of the males were selected. The direct responses to the selection for F, and correlated responses for the number of eggs set (Ie), the number of total dead embryos (M), the maximum duration of fertility (Dm) and the number of hatched mule ducklings (H) were measured by studying the differences across the generations of selection between the phenotypic value averages in the S and C lines. The predicted genetic responses were calculated by studying the differences between the S and C lines in averaged values of five traits of the BLUP animal model. The selection responses and the predicted responses showed similar trends. There was no genetic change for Ie. After seven generations * Correspondence and reprints E-mail: taichein@mail.ncku.edu.tw 598 Y.S. Cheng et al.of selection, the average selection responses per generation were 0.40, 0.33, 0.42, 0.41 genetic standard deviation units for F, M, Dm, and H respectively. Embryo viability was not impaired by this selection. For days 2-8 after AI, the fertility rates (F/Ie) were 89.2% and 63.8%, the hatchability rates (H/F) were 72.5% and 70.6%, and (H/Ie) were 64.7% and 45.1% in the S and C lines respectively. It was concluded that upward selection on the number of fertile eggs after a single AI with pooled Muscovy semen may be effective in ducks to increase the duration of the fertile period and the fertility and hatchability rates with AI once a week instead of twice a week.selection response / fertile egg / Brown Tsaiya / Muscovy / duck

Selection responses in duration of fertility and its consequences on hatchability in the intergeneric crossbreeding of ducks

“…From 1992 to 2003, a selected line (S) and a control line (C) were contemporaneously maintained under the same standardised conditions of feeding and management at the LRI-COA experimental farm in Hsinhua, Tainan, and as described in Cheng et al (2002). These two lines originated from the same gene pool: 106 Brown Tsaiya female ducks and 28 Brown Tsaiya males of Line 105-assumed unrelated-were used as the founder stock (G0).…”

“…The schedule of the selection experiment is described in Poivey et al (2001) for the founder birds (G0), from the first to the 6th generation (G1 to G6), and in Cheng et al (2002) to the 8th generation (from G1 to G8). From 1992 to 2003, a selected line (S) and a control line (C) were contemporaneously maintained under the same standardised conditions of feeding and management at the LRI-COA experimental farm in Hsinhua, Tainan, and as described in Cheng et al (2002).…”

“…In order to study what genetic progress could be achieved by increasing the duration of the fertile period, the Livestock Research Institute, Council of Agriculture (LRI-COA), Hsinhua, Tainan, initiated a selection experiment for an increased number of fertile eggs (F) (measured by candling on d 7 after egg setting) in the Brown Tsaiya female duck after a single AI with pooled Muscovy semen, using a selected and a control (unselected) line (Cheng, 1995). Cheng et al (2002) have established by the analysis of the first 7 generations that selection in order to extend the fertile period is possible. The effects on the duration of fertility and hatchability rates remain to be evaluated.…”

“…The goal of this work was thus, using the logistic regression models, to estimate the correlated responses in durations of fertility and hatchability rates to selection, over 10 generations, in the Brown Tsaiya female duck for number of fertile eggs after a single insemination. The data of Cheng et al (2002) and the three following generations of selection were included in the analysis in order to fit the logistic curves. Furthermore, the effect of that selection on embryo viability was examined.…”

A novel non-synonymous SNP of the COLX gene and its association with duck reproductive traits

“…The CL and SL ducks were bred from 20/11 sires to 49/49 dams, respectively. The procedures of the selection experiment for the duration of fertility were described by Cheng et al [27,28]. The phenotype traits, consisting of the egg weight at 40 weeks of age (EW40), number of eggs to 40 weeks of age (EN40), hatchability rate (HR), fertility rate (FR) and maximum duration of fertility (MDF) were used for polymorphismetrait association analysis.…”