Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2017 Feb;30(2):206-210.
doi: 10.5713/ajas.16.0235. Epub 2016 Jun 9.

Estimation of L-threonine requirements for Longyan laying ducks

A M Fouad  1   2 , H X Zhang  1 , W Chen  1 , W G Xia  1 , D Ruan  1 , S Wang  1 , C T Zheng  1
Affiliations

Estimation of L-threonine requirements for Longyan laying ducks

A M Fouad et al. Asian-Australas J Anim Sci. 2017 Feb.

Abstract

Objective: A study was conducted to test six threonine (Thr) levels (0.39%, 0.44%, 0.49%, 0.54%, 0.59%, and 0.64%) to estimate the optimal dietary Thr requirements for Longyan laying ducks from 17 to 45 wk of age.

Methods: Nine hundred Longyan ducks aged 17 wk were assigned randomly to the six dietary treatments, where each treatment comprised six replicate pens with 25 ducks per pen.

Results: Increasing the Thr level enhanced egg production, egg weight, egg mass, and the feed conversion ratio (FCR) (linearly or quadratically; p<0.05). The Haugh unit score, yolk color, albumen height, and the weight, percentage, thickness, and breaking strength of the eggshell did not response to increases in the Thr levels, but the albumen weight and its proportion increased significantly (p<0.05), whereas the yolk weight and its proportion decreased significantly as the Thr levels increased.

Conclusion: According to a regression model, the optimal Thr requirement for egg production, egg mass, and FCR in Longyan ducks is 0.57%, while 0.58% is the optimal level for egg weight from 17 to 45 wk of age.

Keywords: Laying Duck; Requirement; Threonine.

PubMed Disclaimer

References

    1. Kidd MT, Kerr BJ. L-threonine for poultry: A review. J Appl Poult Res. 1996;5:358–67.
    1. Mao X, Zeng X, Qiao S, Wu G, Li D. Specific roles of threonine in intestinal mucosal integrity and barrier function. Front Biosci. 2011;3:1192–200. - PubMed
    1. Kidd MT. Nutritional modulation of immune function in broilers. Poult Sci. 2004;83:650–7. - PubMed
    1. Fisher ML, Leeson S, Morrison WD, Summers JD. Feather growth and feather composition of broiler chickens. Can J Anim Sci. 1981;61:769–73.
    1. Lehmann D, Pack M, Jeroch H. Effects of dietary threonine in starting, growing, and finishing turkey toms. Poult Sci. 1997;76:696–702. - PubMed

LinkOut - more resources