1
|
Alaraji F. An innovative protocol to increase egg production of chicken layers. PLoS One 2024; 19:e0305099. [PMID: 38843257 PMCID: PMC11156288 DOI: 10.1371/journal.pone.0305099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 05/22/2024] [Indexed: 06/09/2024] Open
Abstract
This study investigated the effects of different doses of limestone, light durations, light intensities, and vitamins on both the productive performance and egg quality. The study utilized two rearing houses (control and treatment), each accommodating 75000 Lohmann Brown Classic chicks reared in open-sided rearing cages from one day old until they reached 89 weeks of age. Throughout the laying period, the hens were subjected to a specific light regimen (light = 14 h; dark = 10 h a day). At the end of experiment, the treatment group displayed significant (p<0.05) differences compared to the control group across various parameters. Notably, the treatment group exhibited lower daily feed intake (treatment: 112 g/bird vs control: 115 g/bird), 9.6% higher egg production (treatment: 78.5% vs control: 68.9%), lower body weight (treatment: 2057 g vs control: 2073 g), lower feed conversion ratio (FCR)/egg (treatment: 1.44 vs control: 1.69), higher egg weight (treatment: 69.4 g vs control: 68.5 g), greater egg mass (treatment: 56.14 vs control: 48.76), greater shell thickness (treatment: 3.52 mm vs control: 3.44 mm), and greater shell weight (treatment: 9.3 g vs control: 8.79 g). However, the albumin weight, yolk weight, yolk diameter, shape index, and Haugh units (HU) were not significantly (p˃0.05) affected after 75 weeks of treatment when compared with those of the control group. Therefore, this study is the first of its kind to demonstrate that different ratios of limestone, different durations and intensities of light, and different vitamin supplementation doses in the treatment group (subjected to the novel rearing recommendations described in this study) may yield a profit of 180,541 USD, exceeding the baseline profit of the control group (subjected to conventional rearing methods).
Collapse
Affiliation(s)
- Furkan Alaraji
- Department of Pathology and Poultry Diseases, University of Kufa, Kufa, Al-Najaf Province, Iraq
| |
Collapse
|
2
|
Arulnathan V, Turner I, Bamber N, Ferdous J, Grassauer F, Doyon M, Pelletier N. A systematic review of potential productivity, egg quality, and animal welfare implications of extended lay cycles in commercial laying hens in Canada. Poult Sci 2024; 103:103475. [PMID: 38364604 PMCID: PMC10877952 DOI: 10.1016/j.psj.2024.103475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/09/2024] [Accepted: 01/12/2024] [Indexed: 02/18/2024] Open
Abstract
Lay cycle lengths in the Canadian egg industry are currently 50 to 52 wk (68-70 wk of age). In light of increased productivity in commercial laying hens over the last few decades, the much longer lay cycle lengths already implemented in other countries, extending lay cycle lengths in Canada, should be considered with careful attention to potential environmental, economic, and animal welfare implications. However, there is a lack of information in the public domain that provides robust evidence of performance levels and potential trade-offs to support comprehensive consideration of the desirability of extending lay cycles beyond current Canadian norms. Hence, a systematic literature review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was undertaken. Data collection focused primarily on information related to feed-, flock management-, and hen genetics/physiology-related interventions that were studied in literature to support extension of lay cycles (review objective 1), and compiling and analyzing productivity, egg quality, and animal welfare outcomes reported at 70 wk of age or beyond (review objective 2). Several feed-related interventions such as high-protein diets, and probiotics supplements, and flock management interventions such split-feeding were found to potentially improve productivity, and especially egg quality, outcomes in the late laying phase. More studies with bigger flock sizes and in commercial lay facilities need to be undertaken before any of these interventions can be definitively recommended for commercial egg production. Under objective 2, productivity was found to be at acceptable levels well beyond 70 wk of age. Performance on most egg quality traits and animal welfare indicators were also at acceptable levels past 70 wk of age but increased variability was observed beyond ∼80 wk of age. There were also inconclusive indications on how hens in caged housing and white laying hens fare relative to hens in noncaged housing and brown-type layers during the late laying phase. Economic data were limited but suggested that lay cycle lengths beyond 90 wk might not generated net economic benefits.
Collapse
Affiliation(s)
- Vivek Arulnathan
- FIP 226, Food Systems PRISM Lab, Fipke Centre for Innovative Research, University of British Columbia Okanagan, Kelowna, BC, V1V 1V7, Canada.
| | - Ian Turner
- FIP 226, Food Systems PRISM Lab, Fipke Centre for Innovative Research, University of British Columbia Okanagan, Kelowna, BC, V1V 1V7, Canada
| | - Nicole Bamber
- FIP 226, Food Systems PRISM Lab, Fipke Centre for Innovative Research, University of British Columbia Okanagan, Kelowna, BC, V1V 1V7, Canada
| | - Jannatul Ferdous
- FIP 226, Food Systems PRISM Lab, Fipke Centre for Innovative Research, University of British Columbia Okanagan, Kelowna, BC, V1V 1V7, Canada
| | - Florian Grassauer
- FIP 226, Food Systems PRISM Lab, Fipke Centre for Innovative Research, University of British Columbia Okanagan, Kelowna, BC, V1V 1V7, Canada
| | - Maurice Doyon
- Paul-Comtois, Laval University, Quebec City, QC, G1V 0A6, Canada
| | - Nathan Pelletier
- FIP 226, Food Systems PRISM Lab, Fipke Centre for Innovative Research, University of British Columbia Okanagan, Kelowna, BC, V1V 1V7, Canada
| |
Collapse
|
3
|
Liu Y, Uyanga VA, Jiao H, Wang X, Zhao J, Zhou Y, Lin H. Effects of feeding strategies on eggshell quality of laying hens during late laying period. Poult Sci 2022; 102:102406. [PMID: 36566661 PMCID: PMC9801208 DOI: 10.1016/j.psj.2022.102406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 11/29/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022] Open
Abstract
Insufficient calcium supply during the dark period is an important reason for deteriorated eggshell quality in laying hens. In the present study, the feeding time of hens was altered in order to investigate whether the changes in feeding time and feed consumption could influence the laying performance and eggshell quality of hens. A total of 192, 60-wk-old Hy-line Brown hens with similar body weight and laying rate were obtained. The hens were randomly divided into 4 groups and subjected to the following feeding strategies: feeding 3 times a day (control group, CON), or feeding once a day in the morning at 08:00 (MF), in the noon at 12:00 (NF), or in the afternoon at 16:00 (AF), respectively. The feeding strategies had no significant effect (P > 0.05) on laying rate, egg weight, and egg mass. Although the feed intake did not differ among treatments, the time phase of feed consumption was changed. From 15:00 to 21:00 h, hens consumed 49.7%, 42.4%, 49.1%, and 70.8% of daily feed intake in the CON, MF, NF, and AF groups, respectively. Feeding strategy had no detectable influence (P > 0.05) on egg shape index, eggshell strength, and eggshell percentage. Compared to CON, AF hens tended to have a higher eggshell thickness (P = 0.053). In MF and NF treatments, plasma calcium (Ca), phosphorus (P) levels, and alkaline phosphatase (ALP) activity did not differ (P > 0.05) compared with CON. In contrast, AF-hens had lower Ca and P levels, but a higher ALP activity than CON (P < 0.01). The AF hens had higher uterine fluid Ca than MF and NF hens (P < 0.05). Compared to CON, the expression level of CaBP-D28K was increased in the shell gland mucosa of MF-hens. Also, MF-, NF-, and AF-hens had higher Osteopontin (OPN) expression level (P < 0.05), whereas NF had a higher expression of OC-116 (P < 0.01). In conclusion, the results indicated that feeding in the afternoon changed the pattern of feed consumption and exerted a positive influence on eggshell thickness.
Collapse
Affiliation(s)
- Yu Liu
- College of Animal Science and Technology, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Key Laboratory of Efficient Utilization of Non-grain Feed Resources (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Taian, Shandong 271018, China
| | - Victoria Anthony Uyanga
- College of Animal Science and Technology, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Key Laboratory of Efficient Utilization of Non-grain Feed Resources (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Taian, Shandong 271018, China
| | - Hongchao Jiao
- College of Animal Science and Technology, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Key Laboratory of Efficient Utilization of Non-grain Feed Resources (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Taian, Shandong 271018, China
| | - Xiaojuan Wang
- College of Animal Science and Technology, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Key Laboratory of Efficient Utilization of Non-grain Feed Resources (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Taian, Shandong 271018, China
| | - Jingpeng Zhao
- College of Animal Science and Technology, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Key Laboratory of Efficient Utilization of Non-grain Feed Resources (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Taian, Shandong 271018, China
| | - Yunlei Zhou
- College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, China
| | - Hai Lin
- College of Animal Science and Technology, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Key Laboratory of Efficient Utilization of Non-grain Feed Resources (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Taian, Shandong 271018, China,Corresponding author:
| |
Collapse
|
4
|
Li L, Liu Z, Fang B, Xu J, Dong X, Yang L, Zhang Z, Guo S, Ding B. Effects of Vitamin A and K3 on Immune Function and Intestinal Antioxidant Capacity of Aged Laying Hens. BRAZILIAN JOURNAL OF POULTRY SCIENCE 2022. [DOI: 10.1590/1806-9061-2021-1572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- L Li
- Wuhan Polytechnic University, China
| | - Z Liu
- Wuhan Polytechnic University, China
| | - B Fang
- Wuhan Polytechnic University, China
| | - J Xu
- Wuhan Polytechnic University, China
| | - X Dong
- Zhejiang University, China
| | - L Yang
- HuBei Horwath Biotechnology Co., Ltd, China
| | - Z Zhang
- Wuhan Polytechnic University, China
| | - S Guo
- Wuhan Polytechnic University, China
| | - B Ding
- Wuhan Polytechnic University, China
| |
Collapse
|
5
|
Poudel I, McDaniel C, Schilling M, Pflugrath D, Adhikari P. Role of conventional and split feeding of various limestone particle size ratios on the performance and egg quality of Hy-Line® W-36 hens in the late production phase. Anim Feed Sci Technol 2022. [DOI: 10.1016/j.anifeedsci.2021.115153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
6
|
Guo S, Niu J, Xv J, Fang B, Zhang Z, Zhao D, Wang L, Ding B. Interactive effects of vitamins A and K 3 on laying performance, egg quality, tibia attributes and antioxidative status of aged Roman Pink laying hens. Animal 2021; 15:100242. [PMID: 34091224 DOI: 10.1016/j.animal.2021.100242] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 03/28/2021] [Accepted: 03/30/2021] [Indexed: 12/15/2022] Open
Abstract
Extending laying cycle is a tendency in hen breeding, but egg quality declines as laying hens age. The present study was conducted to investigate the interactive effects of vitamins A and K3 on laying performance, egg and tibia quality, and antioxidative status of aged Roman Pink laying hens. In a 3 × 3 factorial arrangement, 1 080 87-week-old laying hens were allocated to nine groups with eight replicates in each group. Deficient, adequate and excess vitamins A (0, 7 000 and 14 000 IU/kg) and K3 (0, 2.0 and 4.0 mg/kg) were supplemented into a basal diet with 1 320 IU/kg of vitamin A and 0.5 mg/kg of vitamin K3. After 2 weeks of adaption to basal diet, hens were fed corresponding diets for 8 weeks. Vitamins A and K3 did not significantly affect the laying performance. However, they showed interactive effects on yolk ratio at week 93 as well as tibia weight and diameter (P < 0.05), and hens fed deficient vitamins A and K3 had the highest yolk ratio and tibia weight, but the lowest tibia diameter. Compared with deficient addition, adequate or excess vitamins A and K3 increased yolk color at weeks 93 and 97 (P < 0.05). Compared with hens fed deficient or excess vitamins, hens fed adequate vitamins A and K3 had higher eggshell strength at week 93 or 97 (P < 0.05). Increasing vitamin A elevated plasma total superoxide dismutase (T-SOD) activity and decreased hepatic glutathione peroxidase (GSH-Px) activity (P < 0.05). Excess vitamin K3 increased hepatic T-SOD activity (P < 0.05). Vitamins A and K3 exhibited interaction on the activities of antioxidative enzymes in eggshell gland (P < 0.05), and adequate or excess vitamins A and K3 increased the activities of GSH-Px, T-SOD and catalase (CAT). Adequate and excess vitamin A up-regulated the mRNA expression of GSH-Px1, GSH-Px3 and SOD1 in eggshell gland (P < 0.05). Vitamins A and K3 showed interactive effects on CAT mRNA expression in eggshell gland (P < 0.05) and hens fed adequate vitamins A and K3 had the highest CAT mRNA levels. In conclusion, dietary addition of vitamins A and K3 improved the eggshell quality and yolk color as well as antioxidative status in eggshell gland of aged laying hens. Adequate vitamins A and K3 showed beneficial effects and excess levels did not exhibit superior effects.
Collapse
Affiliation(s)
- S Guo
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan 430023, China
| | - J Niu
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan 430023, China
| | - J Xv
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan 430023, China
| | - B Fang
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan 430023, China
| | - Z Zhang
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan 430023, China
| | - D Zhao
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan 430023, China
| | - L Wang
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan 430023, China
| | - B Ding
- Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan 430023, China.
| |
Collapse
|
7
|
Gan L, Zhao Y, Mahmood T, Guo Y. Effects of dietary vitamins supplementation level on the production performance and intestinal microbiota of aged laying hens. Poult Sci 2020; 99:3594-3605. [PMID: 32616256 PMCID: PMC7597815 DOI: 10.1016/j.psj.2020.04.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 03/08/2020] [Accepted: 04/01/2020] [Indexed: 12/14/2022] Open
Abstract
The objective of this study was to investigate the effects of higher vitamins supplementation level on the performance, immunity, and intestinal microbiota of old laying hens. Twelve birds were randomly chosen from 312 healthy, 65-wk-old Hy-Line Brown layers for sampling after a 7-wk acclimation period. The remaining 300 hens were randomly allocated to 1 of 4 dietary treatments for a 13-wk feeding trial: basal diet (CON), basal diet with 2-fold supplementation level of lipid-soluble vitamins (LV), 2-fold supplementation level of water-soluble vitamins (WV), or 2-fold supplementation level of both lipid-soluble and water-soluble vitamins (BV), respectively. Compared with 72-wk-old laying hens, the 85-wk-old laying hens showed declined egg quality, which implied by inferior eggshell strength and yolk color (P < 0.05). However, after 13 wks feeding trial, the birds in WV group had higher yellowness of yolk color, and LV group had increased laying rate (P < 0.05) compared with CON. Meanwhile, WV and/or BV groups showed improved GSH/GSSG levels in liver and increased secretory immunoglobulin A concentrations in jejunum compared with CON (P < 0.05). In addition, higher dietary vitamin supplementation levels significantly altered the composition of intestinal microbiota, as evidenced by increased abundance of ileal Lactobacillus, whereas reduced richness of ileal Romboutsia, Turicibacter, and cecal Faecalibacterium (P < 0.05) in WV group and increased cecal Megasphaera and Phascolarctobacterium (P < 0.05) in LV group compared with CON group. In conclusion, higher vitamin supplementation levels in the diet could improve laying performance and egg quality of aged hens, which was closely correlated with the increased abundance of beneficial microbiota in the intestine.
Collapse
Affiliation(s)
- Liping Gan
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, People's Republic of China
| | - Yizhu Zhao
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, People's Republic of China
| | - Tahir Mahmood
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, People's Republic of China
| | - Yuming Guo
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, People's Republic of China.
| |
Collapse
|
8
|
Gan L, Fan H, Nie W, Guo Y. Ascorbic acid synthesis and transportation capacity in old laying hens and the effects of dietary supplementation with ascorbic acid. J Anim Sci Biotechnol 2018; 9:71. [PMID: 30305897 PMCID: PMC6166276 DOI: 10.1186/s40104-018-0284-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 08/15/2018] [Indexed: 02/07/2023] Open
Abstract
Background Laying hens over 75 weeks of age commonly show great declines in immunity and production performance. It is unclear whether these declines can be relieved by supplementing with ascorbic acid (AA) in feed. Two trials were conducted to investigate the synthesis and metabolism of AA in layers of different ages and the effects of dietary supplemental AA on the performance and the immune and antioxidant statuses of 78 weeks old hens. Methods In Exp. 1, equal numbers (24 hens) of 35 weeks old (Young) and 75 weeks old (Old) layers were fed the same diet without AA supplementation for 4 weeks. In Exp. 2, 360 healthy 78 weeks old laying hens were randomly assigned to 4 treatments (basal diet supplemented with 0, 0.25, 0.5, or 1 g AA/kg diet) in an 8-week feeding trial. Results The old hens tended to have decreased L-gulonolactone oxidase (GLO) synthase activity in the kidney and liver than that of the young hens (P = 0.07 and P = 0.05, respectively). Compared with the young hens, the old hens had lower hepatic antioxidant capacity allowing for the lower thioredoxin (TXN), thioredoxin reductase (TXNR) and cytochrome b5 reductase (CYB5R) gene expression (P < 0.05), whereas increased sodium-dependent vitamin C transporter (SVCT) 1 expression levels in the ileum and kidney and enhanced splenic and hepatic AA concentrations (P < 0.05). Dietary supplementation with AA significantly decreased GLO enzyme activity but increased splenic AA concentration and anti-bovine serum albumin IgG levels (P < 0.05) and tended to increase CD4+ T lymphocyte numbers (P = 0.06) in serum. Supplementation of 0.25 g AA/kg diet significantly increased hepatic total antioxidant capacity (T-AOC, P < 0.05) relative to the control group. Conclusions Laying hens could synthesize AA in both the kidney and the liver, though the GLO enzyme activities were 100 times greater in kidneys than in livers. The old laying hens had greater absorption and reabsorption capacity and higher AA retention in some tissues that did the young hens. Dietary supplementation of AA can improve the health of old layers by enhancing immunity and antioxidant capacity.
Collapse
Affiliation(s)
- Liping Gan
- The State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, 100193 People's Republic of China
| | - Hao Fan
- The State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, 100193 People's Republic of China
| | - Wei Nie
- The State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, 100193 People's Republic of China
| | - Yuming Guo
- The State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, 100193 People's Republic of China
| |
Collapse
|
9
|
Molnár A, Kempen I, Sleeckx N, Zoons J, Maertens L, Ampe B, Buyse J, Delezie E. Effects of split feeding on performance, egg quality, and bone strength in brown laying hens in aviary system. J APPL POULTRY RES 2018. [DOI: 10.3382/japr/pfy011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
10
|
Molnár A, Maertens L, Ampe B, Buyse J, Zoons J, Delezie E. Effect of different split-feeding treatments on performance, egg quality, and bone quality of individually housed aged laying hens. Poult Sci 2018; 97:88-101. [PMID: 29077907 DOI: 10.3382/ps/pex255] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 08/24/2017] [Indexed: 11/20/2022] Open
Abstract
In order to try to combat the effect of age on eggshell quality in aged laying hens, 5 split-feeding treatments were compared with conventional feeding between 75 and 92 wk of age. In the conventional treatment (T1), the same morning (M) and afternoon (A) diet was fed containing fine (FL) and coarse (CL) limestone at a 50:50 ratio. In the split treatments, the ratio of FL and CL was 50:50 or 30:70, and time of administration (M/A) differed. The following treatments were given: T2 = 50FL-M:50CL-A, T3 = 50CL-M:50FL-A, T4 = 30FL-M:20FL-A+50CL-A, T5 = 30FL-M:70CL-A, and T6 = 0M:30FL-A+70CL-A. A total of 12 individually housed Dekalb white hens was used per treatment. Feed intake, nutrient intake, and laying % was lower in T1 compared to all split treatments (P ≤ 0.001). Due to this low performance in T1, split feeding could not be compared to the conventional system in this trial. By the end of the trial, eggshell quality was improved in T1 as a result of low laying % and more frequent and longer laying pauses. In the split treatments, laying % and feed intake were similar, except in T3 in which a decrease was observed after 81 wk (P ≤ 0.05). Egg weight was higher in T5 and T6 due to higher total and morning protein intake compared to T3 (P ≤ 0.05). Feeding only 50FL-A in T3 not only resulted in lower performance but also in consistently lower shell thickness, indicating a negative effect of suboptimal limestone supplementation. In the split-feeding system, the most optimal combination of morning and afternoon diet was a morning diet with only FL and an afternoon diet with only CL (T2), which both provided ∼50% of the total daily Ca intake. Shell breaking strength and dynamic stiffness could be maintained on this diet between 75 and 92 weeks. Decreasing the amount of Ca in the morning and increasing it in the afternoon did not improve shell quality traits. Bone quality was not affected by limestone particle size or inclusion level in the split-feeding system.
Collapse
Affiliation(s)
- A Molnár
- Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Animal Sciences Unit, Scheldeweg 68, 9090, Melle, Belgium.,Experimental Poultry Center, Poiel 77, 2440, Geel, Belgium.,KU Leuven, Division Animal and Human Health Engineering, Kasteelpark Arenberg 30 / bus 2456, 3001, Heverlee, Belgium
| | - L Maertens
- Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Animal Sciences Unit, Scheldeweg 68, 9090, Melle, Belgium
| | - B Ampe
- Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Animal Sciences Unit, Scheldeweg 68, 9090, Melle, Belgium
| | - J Buyse
- KU Leuven, Division Animal and Human Health Engineering, Kasteelpark Arenberg 30 / bus 2456, 3001, Heverlee, Belgium
| | - J Zoons
- Experimental Poultry Center, Poiel 77, 2440, Geel, Belgium
| | - E Delezie
- Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Animal Sciences Unit, Scheldeweg 68, 9090, Melle, Belgium
| |
Collapse
|