Search

Dietary vitamin E supplementation has been indicated to enhance the antioxidant capacity of breeders. As breeders age, the productive and reproductive performance rapidly decline, and dietary vitamin E supplementation may play a positive role in this process. Two trials were conducted to evaluate the effects of dietary vitamin E supplementation on laying performance, hatchability traits and antioxidant status in molted broiler breeder hens beyond 70 wk. A total of 512 (71-week-old) and 576 (75-week-old) molted Ross 308 breeder hens were assigned to 2 dietary vitamin E groups (6 or 100 mg/kg) and 3 dietary vitamin E groups (100, 200 or 400 mg/kg) for 12 wk, respectively. Eggs were collected and incubated at wk 9. Dietary vitamin E supplementation did not affect the laying performance of hens and the hatchability traits of eggs (P > 0.05). As dietary vitamin E concentration increased, the malonaldehyde (MDA) content in ovarian of hens, egg yolks and serum, brain, and yolk sac of chicks decreased (P < 0.05), the total antioxidant capacity (T-AOC) in serum and ovarian of hens, egg yolks and yolk sac of chicks increased (P < 0.05), and the alpha-tocopherol content in egg yolks increased (P < 0.05). In conclusion, dietary vitamin E supplementation did not influence egg production and hatchability traits. However, based on optimizing the antioxidant status of egg yolks and newly hatched chicks, the suitable vitamin E concentration in the molted broiler breeder hen (beyond 70 wk) diet is at least 200 mg/kg. [ABSTRACT FROM AUTHOR]

Our study aimed to investigate the effects of different dietary vitamin D (VD) combinations during the grower (1-32 d of age) and feed restriction (33-52 d of age) phases on growth performance. We also evaluated sternal morphology, mineralization, and related genes expression of bone metabolism as well as absorption of calcium and phosphorous in duodenal mucosa and kidney in Pekin ducks. During the grower phase, we used 2 VD regimes (Group A: 3,160 IU/kg VD 3 ; Group B: 400 IU/kg VD 3 + 69 μg/kg 25-OH-D 3 ). Each dietary treatment had 50 replicate pens of 10 ducks per pen. During the feed restriction phase, 30 replicate pens selected from Group A and Group B, repetitively, were redivided into 5 different dietary VD regimes to form a 2 × 5 experimental design. Each group consisted of 6 replicates, each with 10 ducks. During the feed restriction phase, we evaluated 5 different dietary VD combinations were as follows: T1: 2,000 IU/kg VD 3 ; T2: 5,000 IU/kg VD 3 ; T3: 3,620 IU/kg VD 3 + 34.5 μg/kg 25-OH-D 3 ; T4: 2,240 IU/kg VD 3 + 69 μg/kg 25-OH-D 3 ; T5: 1,800 IU/kg VD 3 + 80 μg/kg 25-OH-D 3 ). Results showed that Group B combinations with T5 had a better growth performance and breast meat deposition (P < 0.1). Regardless of 5 dietary VD regimes during the feed restriction phase, Group B significantly increased (P < 0.05) 52 d sternal depth and tended to increase (P < 0.1) 52 d sternal defatted weight, ash content, and phosphate (P) content of ducks. A significant interactive effect (P < 0.05) was observed on the mRNA abundance of DMP1 and Sost1 as well as RANKL/OPG in sternum and of VDR in duodenal mucosa of ducks at 52 d of age between dietary VD combinations during 2 phases. These results indicated that dietary VD regimes during the grower phase could affect the effectiveness of dietary VD regimes during the feed restriction phases; Dietary VD combinations of both phases could affect the genes expression of bone formation and the absorption as well as reabsorption of calcium and phosphorus in duodenum and kidney., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

In our previous experiment, we found that fats with pre-emulsification (PreE), a new supplemented mode of emulsifier, had an improved bioavailability for Pekin ducks than fats without PreE based on dietary EE utilization. Therefore, this study was conducted to investigate the effects of the supplemented mode of emulsifier (PreE vs. emulsifier direct supplementation) on the growth performance, serum biochemical index, quality of meat and skin fat, and nutrient utilization in Pekin ducks. A total of 640 healthy 10-day-old Pekin male ducks (408.65 ± 12.00 g) were randomly allocated into 4 treatments with 16 replicates of 10 birds each. The 4 dietary treatments were as follows: the positive control group (PC; the oil supplemented amount of 6%), the negative control group (NC; the oil supplemented amount of 5.4%), the emulsifier group (E; NC diet with an emulsifier added directly), and the oil pre-emulsification group (PreE; NC diet with oil PreE). The results showed reducing the amount of fat in the diet (NC vs. PC) significantly decreased growth performance and quality of skin fat, and affected serum lipid metabolism (P < 0.05). Interestingly, the body weight (BW), body weight gain (BWG), and the shear force of skin fat were increased, but the feed to gain ratio (F/G) was markedly decreased in the PreE group (P < 0.05) compared to those in the NC group, and these levels were similar to those in the PC group (P > 0.05). Additionally, the utilization of dietary dry matter (DM), ether extract (EE), and total phosphorous (TP) were increased, but the activity of aspartate aminotransferase (AST) in serum was decreased in the PreE group compared to those in the NC group (P < 0.05). Furthermore, compared to the E group, the F/G was decreased (P < 0.05), and the utilization of dietary EE, the shear force of skin fat and content of collagen in skin fat were markedly increased (P < 0.05) in the PreE group. However, no differences were observed (P > 0.05) in growth performance between the group administered a direct supplementation of emulsifier and the control groups (PC and NC). These results indicate that the negative effect of reducing the oil supplementation amount (-0.6%) in the diet can be restored by supplementation with emulsifier, especially by oil with PreE., Competing Interests: DISCLOSURES None of the authors have any conflicts of interest to declare., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

This study aimed to investigate the effect of a high-fat diet on the growth performance, serum, liver, and skin lipid metabolism as well as the fatty acids composition of liver and skin fat in Pekin ducks from 10 to 40 d of age based on a pair-fed group. Two hundred forty healthy male ducks (10 d old, 470.53 ± 0.57 g) were randomly divided into 3 groups (8 replicates per cage of 10 ducks): a normal diet (ND, 3% fat), a high-fat diet (HFD, 9% fat), and a pair-fed diet (PFD, given the ND in an amount equal to that consumed of the HFD to eliminate the effects of feed intake). The results were as follows: compared to ND feeding, HFD feeding significantly decreased (P < 0.05) the feed intake and feed:gain ratio (F:G), along with serum triglyceride and nonesterified fatty acid contents. When compared with the ND and PFD, the HFD significantly decreased (P < 0.05) the liver weight and inhibited hepatic de novo lipogenesis (glucose-6-phosphate dehydrogenase and malate dehydrogenase activities), β-oxidation (carnitine palmitoyltransferase-1 content), and decreased saturated fatty acids and monounsaturated fatty acids deposition. Moreover, the HFD significantly increased (P < 0.05) the total fat content, lipid droplet area, and polyunsaturated fatty acids (PUFAs) content in the liver, as well as the abdominal fat weight, subcutaneous fat weight, the total fat and PUFAs content in skin fat. These results suggested that the HFD improved feed efficiency, which was related to HFD feeding inhibiting hepatic de novo lipogenesis and β-oxidation and promoting the deposition of fat in skin as well as altering the fatty acids composition of the liver and skin fat in Pekin ducks., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

The study aimed to investigate the effects of dietary distillers dried grains with solubles (DDGS) levels on growth performance, carcass characteristic, serum biochemical indexes, meat physical and chemical quality, nutrient utilization, and standardized ileal digestibility of amino acids (SIDAA) in Pekin ducks aged 11 to 42 d based on the evaluation of its SIDAA. A total of 560 eleven-day-old Cherry Valley ducks were randomly allotted to 5 treatments with 7 replicate pens per treatment and 16 ducks per pen based on the average body weight. Six isonitrogenous and isocaloric experimental diets were formulated on a digestible amino acid basis to produce diets containing 0, 5, 10, 15, and 20% DDGS, respectively. With increasing of dietary DDGS levels, a linear and quadratic reduction (P < 0.05) was observed in the body weight (BW) at d 42, average day gain (ADG) and average day feed intake (ADFI) from d 11 to 42, breast meat yield, the moisture and protein content in the breast meat, and dietary DM and EE utilization. Moreover, a linear and quadratic increase (P < 0.05) was observed in the b* value of the breast meat and serum total cholesterol and triglyceride concentrations. Compared with the control group, the group with 10% inclusion of DDGS exhibited no adverse effect on growth performance, carcass characteristics, serum biochemical indexes, meat physical and chemical quality, nutrient utilization, and the SIDAA of the diets (P > 0.05). These results suggested that 10% of corn DDGS can function as an alternative ingredient to corn and soybean meal, and the optimal levels of DDGS in the diets of ducks aged from 11 to 42 d depends more on its quality., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

The study aimed to determine the ileal phosphorus (P) digestibility (iPD) and the excreta P retention (ePR) of 5 monodicalcium phosphate (MCP) samples and 3 dicalcium phosphate (DCP) samples in broiler chickens and in Pekin ducks using the substitution method. A total of 720, 21-d-old Arbor Acres broiler chickens in experiment 1 and 720, 15-d-old Pekin ducks in experiment 2 were randomly allocated to 9 dietary treatments with 8 replicate cages (10 birds/cage) based on the similar mean body weight, respectively. The collection of excreta (for 72 h after a 3-d acclimation) and ileal digesta (after 6 d of feeding experimental diets) was done. The results showed the average iPD/ePR of MCP and DCP for broilers were 83.11%/74.52% and 75.34%/69.46% and for ducks were 79.37%/80.02% and 75.74%/76.44%, respectively. The iPD/ePR of MCP in broilers and the ePR of MCP in ducks were markedly higher (P < 0.05) than those of DCP. Our data suggest that using the substitution method to evaluate the bioavailability of feed phosphates has its own advantages; MCP has higher biological availability than DCP for broilers and ducks., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

The study aimed to investigate the effects of dietary corn germ meal (CGM) levels on growth performance, carcass characteristic, serum biochemical indexes, meat physical and chemical quality, and standardized ileal digestibility of amino acids (SIDAA) in Pekin ducks from 10 to 42 d of age. A total of 420 ten-day-old Cherry Valley ducks were randomly allotted to 5 treatments with 6 replicate cages per treatment and 14 ducks per cages based on mean body weight. Five isonitrogenous and isocaloric experimental diets were formulated on a digestible amino acid basis to produce diets containing 0, 3, 6, 9, or 12% CGM. Results showed: 1) Compared with other groups, ducks fed 12% CGM significantly increased (P < 0.05) the feed to gain ratio. 2) Dietary CGM levels had no effect (P > 0.05) on the carcass traits and breast meat physical quality; but the content of crude protein presented a linear decrease (P < 0.05) in breast meat with increasing dietary CGM levels. 3) Serum biochemical indices (e.g., alanine aminotransferase, aspartate aminotransferase, glucose, high density lipoprotein cholesterol, total cholesterol, triglyceride, total protein, and urea) showed no significant differences among all groups (P > 0.05). 4) The levels of CGM had no significant effect on SIDAA of diets (P > 0.05), except for cysteine which showed a quadratic increase (P < 0.05). These results suggested that the optimal levels of CGM in diets for meat duck aged from 10 to 42 d should be below 9% based on feed to gain ratio and the content of crude protein in breast meat., (Copyright © 2022. Published by Elsevier Inc.)

This study was conducted to investigate the effect of different varieties of rapeseed meal (RSM) with different concentrations of glucosinolates (Gls) and erucic acid (EA) on performance and egg quality of laying ducks. A total of 576 twenty eight-wk-old laying ducks were randomly allocated to 4 treatments. Each treatment had 8 replicates of 18 laying ducks raised in 6 adjacent cages with 3 laying ducks per cage. The control diet was corn soybean meal based without RSM. Three varieties of RSM varying in Gls concentrations were supplemented to the base diet at 10% by substituting soybean meal to formulate the three RSM diets. The experiment lasted 12 wk. Diets with 10% RSM decreased average egg weight (P < 0.01) and feed intake (P = 0.07) compared with the control diet, but there was no significant difference in laying performance among the 3 RSM diets. RSM increased color value (P < 0.05) and crude protein (CP) content (P < 0.05) of yolk compared with the control diet, but had no significant effects on the other egg quality indexes including eggshell strength, albumen height, Haugh unit, and the composition ratio of eggshell, albumen and yolk. RSM decreased total monounsaturated fatty acids (MUFA) (P < 0.01) and increased total polyunsaturated fatty acids (PUFA) (P < 0.01) of yolk, but total saturated fatty acids (SFA) proportions and UFA/SFA ratio of egg yolk were not significantly affected by RSM. RSM increased deposition of trimethylamine (TMA) and 5-vinyl-1,3-oxazolidine-2-thione (5-VOT) in yolk (P < 0.01); moreover, the high Gls RSM increased deposition of TMA (P < 0.01) and 5-VOT in yolk (P < 0.01) compared with the RSM varieties low in Gls. These results suggested that dietary inclusion of 10% RSM decreased egg weight of laying ducks, and affected yolk quality especially yolk color, fatty acid profile, CP, TMA, and 5-VOT content of yolk. Moreover, RSM with higher Gls concentration resulted in higher deposition of TMA and 5-VOT in egg yolk., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

It has been shown that enzyme-treated plant protein can increase performance and promote intestinal health, and save dietary protein. However, our understanding of the effects of enzyme-treated soy protein on performance and intestine function in laying hens, and its rational use, remains limited. The experiment was conducted to study the effect of enzyme-treated soy protein (ETSP) in different nutrient density diets on performance, egg quality, digestive enzyme activity and mRNA expression of amino acid transporters of laying hens. A total of 1 200 Lohmann laying hens (52 wk of age) was randomly divided into a 3 × 2 factorial design that included three nutrient levels: [positive control (PC), metabolisable energy (ME): 2 680 kcal/kg, CP: 15.5%; negative control 1 (NC1), ME: 2 630 kcal/kg, CP: 15%; negative control 2 (NC2), ME:2 580 kcal/kg, CP: 14.5%] and 2 ETSP levels (0 and 0.5%) for 12 weeks. Each treatment had 10 replicates with 20 birds. With the decrease of dietary nutrition density, egg production rate (P = 0.07) and feed conversion ratio (FCR) (P = 0.06) were reduced. Yolk colour was decreased, and yolk index was increased. Supplemented ETSP improved FCR (P = 0.05) and qualified egg rate (P < 0.05). The mass loss rate of egg was decreased after storage for 30 days (P < 0.05). An interaction between nutrient density and ETSP was observed on albumen height and Haugh unit (P < 0.05), and the effects were most noticeable in hens fed 0.5% ETSP in NC2 group. An increase in the activity of trypsin in duodenum (P < 0.05) and the relative expressions of jejunum peptide transporter 1 (PepT1) (P < 0.05) and B 0 system neutral amino acid transport carrier (B 0 AT) mRNA (P < 0.01) was observed during ETSP supplementation. The nutrient density and ETSP supplementation had no significant effect on microbiota in the cecal contents. Overall, the results in this study indicated that the ME decreased 100 kcal/kg and CP decreased 1% in diet of laying hens had a decreasing trend on production performance, no effects on enzyme activity, amino acid transporter mRNA, and gut microbiota, whereas 0.5% ETSP can increase activity of trypsin, PepT1 and B 0 AT mRNA relative expressions, and improve FCR, qualified egg rate., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)