Estimation of L-threonine requirements for Longyan laying ducks

Fouad, A.M.; Zhang, H. X.; Chen, W.; Xia, Weiguang; Ruan, D.; Wang, S.; Zheng, Chuntian

doi:10.5713/ajas.16.0235

Cited by 9 publications

(19 citation statements)

References 25 publications

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“…Similarly, Azzam et al (2014, 2017) found that the addition of Thr to the diet of laying hens increased egg production but did not significantly affect the egg weight. In addition, Fouad et al (2017) showed that a diet containing 0.57% Thr maximized egg production in laying ducks. Ashrafi et al (2011) reported that egg production increased with the dietary threonine level up to 0.67% Thr in the diet, whereas the egg weight decreased as the dietary threonine level increased in broiler breeders (Cobb strain) at 60 wk of age.…”

Section: Resultsmentioning

confidence: 99%

“…In meat-type birds, depression of the growth rate, feed intake, and carcass yield are consequences of Thr deficiency, whereas the effects in laying birds are a low laying rate, egg weight, egg mass, and feed conversion ratio (Azzam et al, 2011; Zhang et al, 2014; Fouad et al, 2017). In addition, Thr is required to improve the secretion of digestive enzymes and to maintain normal populations of useful bacteria when the diet contains a low level of crude protein (Dong et al, 2017).…”

Section: Introductionmentioning

confidence: 99%

“…Previous studies have highlighted the critical effect of Thr supplementation on improving egg production in laying hens and ducks (Azzam et al, 2014, 2017; Fouad et al, 2017). Furthermore, the in ovo injection of Thr improves the performance of chicks and enhances the morphological and functional development of the intestinal mucosa at hatching and at 21 D (Moreira Filho et al, 2019).…”

Section: Introductionmentioning

confidence: 99%

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Effects of dietary threonine supplementation on productivity and expression of genes related to protein deposition and amino acid transportation in breeder hens of yellow-feathered chicken and their offspring

et al. 2019

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This study investigated the effects of the dietary threonine (Thr) levels on the performance, offspring traits, embryo amino acid transportation, and protein deposition in breeder hens of yellow-feathered chickens. In total, 720 breeder hens of Lingnan yellow-feathered chickens were randomly assigned to 1 of 6 dietary treatments, with 6 replicates per treatment (20 birds per replicate). The breeder hens were fed either basal diet (Thr = 0.38%) or basal diet supplemented with 0.12, 0.24, 0.36, 0.48, or 0.60% Thr from 197 to 266 D. There was a positive response in terms of the laying rate after adding different levels of Thr to the diet, but no significant effects on the average daily gain, average daily egg weight, feed conversion ratio, average broken eggs, and unqualified egg rate (P > 0.05). However, the eggshell strength and eggshell percentage decreased in a linear manner as the dietary Thr concentration increased (P = 0.05). Dietary supplementation with Thr had significant effects on the expression of mucin 2 (MUC2) in the uterus and zonula occludens protein 1 (ZO-1) in the duodenum of breeders (P < 0.05). In chick embryos at embryonic age 18 D, significant upregulation of poultry target of rapamycin (pTOR) occurred in the liver and breast muscle, as well as threonine dehydrogenase (TDH) in the thigh, and aminopeptidase (ANPEP) (P < 0.05) in the duodenum and ileum due to dietary Thr supplementation, but there were no effects on MUC2 expression in the duodenum and ileum (P > 0.05). The livability of the progeny broilers tended to increase with the dietary Thr concentration (quadratic, P = 0.08). Thus, dietary supplementation with Thr had positive effects on the laying production by breeder hens and offspring performance, and it also regulated the expression levels of genes related to amino acid transportation and protein deposition. The optimal dietary Thr concentration that maximized the laying rate in yellow-feathered chicken breeders aged 197 to 266 D was 0.68% according to quadratic regression analysis.

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Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Effects of dietary threonine supplementation on productivity and expression of genes related to protein deposition and amino acid transportation in breeder hens of yellow-feathered chicken and their offspring

et al. 2019

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“…Zhang et al [ 26 ] suggested feeding White Pekin ducks, from 14 to 35 d of age, diets containing 0.75, 0.74, and 0.73% Thr to achieve the standardized body weight gain, FCR, and relative breast meat yield (weight), respectively. In contrast, maximizing egg production, egg mass, and feed efficiency in Longyan laying ducks requires 0.57% Thr in the diet from 17 to 45 wk of age according to previous study in this laboratory [ 27 ].…”

Section: Introductionmentioning

confidence: 99%

Nutritional requirements of meat-type and egg-type ducks: what do we know?

Fouad

Ruan²,

Wang³

et al. 2018

J Animal Sci Biotechnol

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The demand for duck meat, duck eggs, and associated products is increasing each year. Classic and modern selection programs have been applied to enhance the economic traits of ducks to satisfy the requirements of consumers and enhance the incomes of producers. The nutritional requirements of unselected ducks may not be adequate, however, to fulfill the potential productivity performance of modern birds, including both meat-type and egg-type ducks. In particular, an imbalanced diet is associated with low productive performance and signs of nutritional deficiency (if insufficient nutrients are supplied), as well as with high feed costs and manure problems that reflect flock health and welfare (if excessive nutrients are supplied). Thus, the main aim of this review is to summarize the results of previous studies that estimated the nutrient requirements of meat-type and egg-type ducks in order to evaluate current knowledge and to identify further issues that need to be addressed. In addition, the results obtained in previous studies are compared in order to understand how to lower commercial feed costs, fulfill the genetic potential of selected ducks, protect the environment from pollution, and satisfy the welfare and health needs of ducks.

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“…Feed conversion ratio (FCR) was calculated as grams of feed per gram of egg mass daily on a replication basis and then presented as the averages for the complete 16-wk study period. Two eggs were collected at random from each replicate at the end of the experimental period to determine egg quality (egg shape index, Haugh unit, yolk colour, eggshell thickness) as described by Fouad et al (2017).…”

Section: Performance and Egg Qualitymentioning

confidence: 99%

Effects of dietary lysine supplementation on performance, egg quality, and development of reproductive system in egg-laying ducks

Fouad

Chen

Ruan

et al. 2017

Journal of Applied Animal Research

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This study was conducted to examine five lysine (Lys) levels (0.75, 0.80, 0.85, 0.90, and 0.95%) to estimate the optimal level of Lys for Longyan laying ducks from 22 to 38 wk of age. Nine hundred Longyan ducks aged 22 wk were assigned randomly to the 5 dietary treatments, where each treatment comprised 6 replicate pens with 30 ducks per pen. Lys had no effects on egg production, egg mass, feed conversion ratio, shape index, Haugh unit, yolk colour, yolk weight, or albumen weight, but the egg weight was improved significantly (P < 0.05) by dietary Lys supplementation, whereas the eggshell thickness, eggshell weight, and eggshell proportion decreased significantly as the Lys levels increased. Dietary supplementation of Lys did not affect the reproductive organ indices or the plasma levels of estradiol, luteinizing hormone, or follicle-stimulating hormone, whereas the plasma level of progesterone declined significantly (P < 0.01) as elevation the concentrations of Lys in the diets. In conclusion, the results indicate that the optimal Lys level in Longyan laying ducks diets is 0.80% to produce eggs with normal egg weight without adverse effects on the eggshell weight, eggshell proportion, or eggshell thickness.

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Estimation of L-threonine requirements for Longyan laying ducks

Cited by 9 publications

References 25 publications

Effects of dietary threonine supplementation on productivity and expression of genes related to protein deposition and amino acid transportation in breeder hens of yellow-feathered chicken and their offspring

Effects of dietary threonine supplementation on productivity and expression of genes related to protein deposition and amino acid transportation in breeder hens of yellow-feathered chicken and their offspring

Nutritional requirements of meat-type and egg-type ducks: what do we know?

Effects of dietary lysine supplementation on performance, egg quality, and development of reproductive system in egg-laying ducks

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