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Marggraff J, Gernand E, Ahlers C, Huchler M, Rautenschlein S, Donat K. Factors associated with keel bone damage - a longitudinal study of commercial layer flocks during the laying period. Br Poult Sci 2024; 65:233-241. [PMID: 38578252 DOI: 10.1080/00071668.2024.2326444] [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: 02/21/2023] [Accepted: 02/03/2024] [Indexed: 04/06/2024]
Abstract
1. Keel bone damage, such as deformations and fractures, is a severe problem regarding animal welfare in layers. To identify risk factors under commercial conditions, 33 layer flocks (22 barn, 11 free range) with white (n = 18), brown (n = 11) and mixed (n = 4) genotypes were examined.2. Keel bone status was frequently scored by palpation throughout the laying period. Data on housing and management conditions were collected. Multiple regression and Generalized Estimating Equations procedure were used for analysis.3. At 65-74 weeks of age, the prevalence of keel bone damage ranged between 26% and 74%. White genotypes and those kept in multi-tier systems developed significantly (p < 0.05) more keel bone damage than brown genotypes or those kept in single-tier systems. Wing feather condition was associated with keel bone damage (p < 0.05), while other investigated variables regarding health, housing and management were not associated.4. In conclusion, housing and management should be adapted to meet the birds' specific needs in multi-tier systems, which may vary for brown and white genotypes. Whether those differences result from genotype associated predispositions or other individual traits remains to be determined.
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Affiliation(s)
- J Marggraff
- Animal Health Service, Thuringian Animal Health Fund, Jena, Germany
| | - E Gernand
- Department of Animal Husbandry, Thuringian State Institute for Agriculture, Jena, Germany
| | - C Ahlers
- Animal Health Service, Thuringian Animal Health Fund, Jena, Germany
| | - M Huchler
- Thuringian Ministry of Labour, Social Affairs, Health, Women and Family, Erfurt, Germany
| | - S Rautenschlein
- Clinic for Poultry, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - K Donat
- Animal Health Service, Thuringian Animal Health Fund, Jena, Germany
- Clinic for Obstetrics, Gynaecology and Andrology with Veterinary Ambulance, Justus-Liebig-University Giessen, Giessen, Germany
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Pulcini D, Mattioli S, Angelucci E, Chenggang W, Cartoni Mancinelli A, Napolitano R, Sirri F, Piscitelli R, Mugnai C, Castellini C. Shape and fractures of carina sterni in chicken genotypes with different egg deposition rates reared indoor or free-range. Sci Rep 2023; 13:22495. [PMID: 38110659 PMCID: PMC10728074 DOI: 10.1038/s41598-023-49909-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 12/13/2023] [Indexed: 12/20/2023] Open
Abstract
Commercial laying hens have high frequency of damage to the keel bone (KB), which causes negative effects on health and welfare. KB damage may consist in fractures (KBF) and deviations (KBD). The aim of the present study was to compare the KB shape, by means of Geometric Morphometric, and the occurrence of fractures in different chicken genotypes reared either free-range (FR) or in enriched cages. Moreover, the relationship between KB shape, genotype and rearing system was analysed. Sixty birds/genotype (2 Italian local breeds, Bionda Piemontese and Robusta Maculata, their crossbreeds with Sasso and Lohmann Brown) were used. All the hens fed the same commercial feed throughout the trial. Body weight, egg production, feed intake and mortality were recorded from 25 to 66 weeks of age. Ca intake (IN) and output (OUT) were estimated and Ca OUT/IN was calculated. FR affected the occurrence of KB deviations but not the shape, whereas the fractures were mainly affected by genotype. Local breeds had a lower prevalence of KBF with similar level of KBD but with different shapes. Crossbreeds seemed to be a suitable compromise between egg deposition rate and occurrence of KB damages.
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Affiliation(s)
- Domitilla Pulcini
- Council for Agricultural Research and Economics, Animal Production and Aquaculture, 00015, Monterotondo, Rome, Italy
| | - Simona Mattioli
- Department of Agricultural, Food and Environmental Sciences, University of Perugia, 06100, Perugia, Italy.
| | - Elisa Angelucci
- Department of Agricultural, Food and Environmental Sciences, University of Perugia, 06100, Perugia, Italy
| | - Wei Chenggang
- Department of Agricultural, Food and Environmental Sciences, University of Perugia, 06100, Perugia, Italy
| | - Alice Cartoni Mancinelli
- Department of Agricultural, Food and Environmental Sciences, University of Perugia, 06100, Perugia, Italy
| | - Riccardo Napolitano
- Council for Agricultural Research and Economics, Animal Production and Aquaculture, 00015, Monterotondo, Rome, Italy
| | - Federico Sirri
- Department of Agricultural and Food Sciences, Alma Mater Studiorum - University of Bologna, 40064, Ozzano dell'Emilia, Italy
| | - Raffaela Piscitelli
- Department of Agricultural and Food Sciences, Alma Mater Studiorum - University of Bologna, 40064, Ozzano dell'Emilia, Italy
| | - Cecilia Mugnai
- Department of Veterinary Sciences, University of Turin, 10095, Turin, Italy
| | - Cesare Castellini
- Department of Agricultural, Food and Environmental Sciences, University of Perugia, 06100, Perugia, Italy
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Sharma MK, Liu G, White DL, Tompkins YH, Kim WK. Graded levels of Eimeria challenge altered the microstructural architecture and reduced the cortical bone growth of femur of Hy-Line W-36 pullets at early stage of growth (0-6 wk of age). Poult Sci 2023; 102:102888. [PMID: 37542924 PMCID: PMC10428119 DOI: 10.1016/j.psj.2023.102888] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 06/16/2023] [Accepted: 06/17/2023] [Indexed: 08/07/2023] Open
Abstract
An experiment was carried out to evaluate the impact of mixed Eimeria challenge on skeletal health of Hy-Line W-36 pullets. A total of 540, 16-day-old pullets were randomly allocated into 5 treatment groups, including a nonchallenged control. A mixed Eimeria species solution containing 50,000 E. maxima, 50,000 E. tenella, and 250,000 E. acervulina oocysts per mL was prepared and challenged to 1 group as a high-dose treatment. The 2-fold serial dilution was done to prepare the medium-high (25,000 E. maxima; 25,000 E. tenella; 125,000 E. acervulina), the medium-low (12,500 E. maxima; 12,500 E. tenella; 62,500 E. acervulina), and the low (6,250 E. maxima; 6,250 E. tenella; 31,250 E. acervulina) dose treatments which were challenged to 3 corresponding groups, respectively. The mineral apposition rate (MAR) was measured from 0 to 14 d post inoculation (DPI) and 14 to 28 DPI using calcein injection. The microstructural architecture of the femur was analyzed using the Skyscan X-ray microtomography (microCT) on 6, 14, and 28 DPI. The results showed that the MAR decreased linearly with an increase in the challenged dose (P < 0.05) during 0 to 14 DPI. The results of microCT revealed that cortical and total BMD, BMC, bone volume (BV), and bone volume as a fraction of tissue volume (BV/TV) of femur decreased both linearly (P < 0.05). Conversely, the total number of pores increased linearly with an increase in challenge dosages on 6 and 14 DPI. Trabecular BMD, BV, BV/TV, trabecular number, and trabecular thickness decreased linearly with an increase in the challenge dosages (P < 0.05) on 6 DPI. Furthermore, Eimeria infection significantly increased the number of osteoclasts and osteoclastic activity (P = 0.001). The result of this study suggests that the mixed Eimeria challenge negatively impacts the quality of skeletal health in a linear or quadratic manner with an increase in the concentration of Eimeria oocysts. The negative impact on long bone development might be due to malabsorption, nutrient deficiency during the infection, along with oxidative stress/inflammation disrupting the balance of osteoblastic and osteoclastic cells and their functions.
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Affiliation(s)
- Milan K Sharma
- Department of Poultry Science, University of Georgia, Athens, GA, 30602 USA
| | - Guanchen Liu
- Department of Poultry Science, University of Georgia, Athens, GA, 30602 USA
| | - Dima L White
- Department of Poultry Science, University of Georgia, Athens, GA, 30602 USA
| | - Yuguo H Tompkins
- Department of Poultry Science, University of Georgia, Athens, GA, 30602 USA
| | - Woo K Kim
- Department of Poultry Science, University of Georgia, Athens, GA, 30602 USA.
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Wei H, Bi Y, Wang Y, Zhao Q, Zhang R, Li J, Bao J. Serum bone remodeling parameters and transcriptome profiling reveal abnormal bone metabolism associated with keel bone fractures in laying hens. Poult Sci 2022; 102:102438. [PMID: 36780704 PMCID: PMC9947423 DOI: 10.1016/j.psj.2022.102438] [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: 08/28/2022] [Revised: 12/08/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
Keel bone fractures affect welfare, health, and production performance in laying hens. A total of one hundred and twenty 35-wk-old Hy-line Brown laying hens with normal keel (NK) bone were housed in furnished cages and studied for ten weeks to investigate the underlying mechanism of keel bone fractures. At 45 wk of age, the keel bone state of birds was assessed by palpation and X-ray, and laying hens were recognized as NK and fractured keel (FK) birds according to the presence or absence of fractures in keel bone. The serum samples of 10 NK and 10 FK birds were collected to determine bone metabolism-related indexes and slaughtered to collect keel bones for RNA-sequencing (RNA-seq), Micro-CT, and histopathological staining analyses. The results showed that the concentrations of Ca, phosphorus, calcitonin, 25-hydroxyvitamin D3, and osteocalcin and activities of alkaline phosphatase and tartrate-resistant acid phosphatase (TRAP) in serum samples of FK birds were lower than those of NK birds (P < 0.05), but the concentrations of parathyroid hormone, osteoprotegerin, and corticosterone in serum samples of FK birds were higher than those of NK birds (P < 0.05). TRAP staining displayed that FK bone increased the number of osteoclasts (P < 0.05). Micro-CT analysis indicated that FK bone decreased bone mineral density (P < 0.05). Transcriptome sequencing analysis of NK and FK bones identified 214 differentially expressed genes (DEGs) (|log2FoldChange| > 1, P < 0.05), among which 88 were upregulated and 126 downregulated. Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) analysis indicated that 14 DEGs related to skeletal muscle movement and bone Ca transport (COL6A1, COL6A2, COL6A3, PDGFA, MYLK2, EGF, CAV3, ADRA1D, BDKRB1, CACNA1S, TNN, TNNC1, TNNC2, and RYR3) were enriched in focal adhesion and Ca signaling pathway, regulating bone quality. This study suggests that abnormal bone metabolism related to keel bone fractures is possibly responded to fracture healing in laying hens.
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Affiliation(s)
- Haidong Wei
- College of Life Science, Northeast Agricultural University, 150030 Harbin, China
| | - Yanju Bi
- College of Animal Science and Technology, Northeast Agricultural University, 150030 Harbin, China
| | - Yulai Wang
- College of Animal Science and Technology, Northeast Agricultural University, 150030 Harbin, China
| | - Qian Zhao
- College of Animal Science and Technology, Northeast Agricultural University, 150030 Harbin, China
| | - Runxiang Zhang
- College of Animal Science and Technology, Northeast Agricultural University, 150030 Harbin, China,Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin 150030, China
| | - Jianhong Li
- College of Life Science, Northeast Agricultural University, 150030 Harbin, China
| | - Jun Bao
- College of Animal Science and Technology, Northeast Agricultural University, 150030 Harbin, China; Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin 150030, China.
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Productive performance, perching behavior, keel bone and other health aspects in dual-purpose compared to conventional laying hens. Poult Sci 2022; 101:102095. [PMID: 36095865 PMCID: PMC9472069 DOI: 10.1016/j.psj.2022.102095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 07/11/2022] [Accepted: 07/26/2022] [Indexed: 11/23/2022] Open
Abstract
Several alternatives to avoid killing male day-old chicks are available. One of these alternatives is to keep dual-purpose chicken strains. The aim of this study was to compare dual-purpose hens (Lohmann Dual, LD) with conventional laying hens (Lohmann Tradition, LT) in terms of performance, animal welfare parameters such as keel bone state and foot pad dermatitis, and perching behavior. We expected a generally equal or even better performance of the dual-purpose hens except for laying performance. Four hundred female day-old chicks were housed in 6 pens (3 pens per strain) and reared until 54 wk of age. Each pen offered a littered area, elevated slatted manure pit, elevated wooden frame with perches or grids and nest boxes on the manure pit. The wooden frame was alternately equipped with perches or grids. The elevated manure pit as well as the elevated structure was accessible via ramp. Productive performance parameters like mortality, total number of eggs and body weight were assessed periodically. In week 49, 132 hens (66 hens per strain) were randomly selected for radiography of the keel bone and assessment of plumage and foot pad state. Perching behavior was analyzed via scan sampling during rearing and laying period, respectively. Statistical analyzes were done with Linear Mixed Effect Model and General Linear Mixed Model. LD had a higher radiographic density than LT hens (P = 0.0016), other keel bone parameters (fracture score, P = 0.36; deformation, P = 0.83) showed no differences. The vast majority of fractures occurring in both strains were located in the caudal part of the keel bone. During the laying period, usage of elevated structures was higher with grids compared to perches (P < 0.001) and in LD compared to LT (P = 0.01). Some animal welfare problems were less frequent in LD compared to LT hens while other problems did not differ between the 2 strains or were even more frequent in LD hens. Grids may be more suitable as resting area than perches and may possibly help to decrease the prevalence of keel bone damage.
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Garant R, Tobalske BW, Sassi NB, van Staaveren N, Widowski T, Powers DR, Harlander-Matauschek A. Wing-feather loss in white-feathered laying hens decreases pectoralis thickness but does not increase risk of keel bone fracture. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220155. [PMID: 35719889 PMCID: PMC9198519 DOI: 10.1098/rsos.220155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 05/24/2022] [Indexed: 05/03/2023]
Abstract
Feather loss in domestic chickens can occur due to wear and tear, disease or bird-to-bird pecking. Flight feather loss may decrease wing use, cause pectoral muscle loss and adversely impact the keel bone to which these muscles anchor. Feather loss and muscle weakness are hypothesized risk factors for keel bone fractures that are reported in up to 98% of chickens. We used ultrasound to measure changes in pectoral muscle thickness and X-rays to assess keel bone fracture prevalence following symmetric clipping of primary and secondary feathers in white- and brown-feathered birds. Four and six weeks after flight feather clipping, pectoralis thickness decreased by approximately 5%, while lower leg thickness increased by approximately 5% in white-feathered birds. This pectoralis thickness decrease may reflect wing disuse followed by muscle atrophy, while the increased leg thickness may reflect increased bipedal locomotion. The lack of effect on muscle thickness in brown-feathered hens was probably due to their decreased tendency for aerial locomotion. Finally, pectoralis thickness was not associated with keel bone fractures in either white- or brown-feathered birds. This suggests that the white-feathered strain was more sensitive to feather loss. Future prevention strategies should focus on birds most susceptible to muscle loss associated with flight feather damage.
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Affiliation(s)
- Renée Garant
- Department of Animal Biosciences, University of Guelph, 50 Stone Road E, Guelph, ON N1G 2W1, Canada
| | - Bret W. Tobalske
- Division of Biological Sciences, University of Montana, 32 Campus Drive, Missoula, MT 59812, USA
| | - Neila Ben Sassi
- Department of Animal Biosciences, University of Guelph, 50 Stone Road E, Guelph, ON N1G 2W1, Canada
| | - Nienke van Staaveren
- Department of Animal Biosciences, University of Guelph, 50 Stone Road E, Guelph, ON N1G 2W1, Canada
| | - Tina Widowski
- Department of Animal Biosciences, University of Guelph, 50 Stone Road E, Guelph, ON N1G 2W1, Canada
| | - Donald R. Powers
- Department of Biology, George Fox University, 414N Meridian Street, Newberg, OR 97132, USA
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Wei H, Feng Y, Ding S, Nian H, Yu H, Zhao Q, Bao J, Zhang R. Keel bone damage affects behavioral and physiological responses related to stress and fear in two strains of laying hens. J Anim Sci 2022; 100:6547233. [PMID: 35275597 PMCID: PMC9030218 DOI: 10.1093/jas/skac076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 03/10/2022] [Indexed: 11/13/2022] Open
Abstract
Keel bone damage (KBD) is more prevalent in alternative laying hen housing systems than in conventional cages, and its incidence differs from strain to strain. However, the information of KBD in Lindian chickens, a native Chinese strain, is limited. To investigate the effect of KBD on fearfulness and physiological indicators of stress in Lindian chickens and commercial laying hens, a total of two hundred 25-wk-old chickens (100 Hy-line Brown and 100 Lindian chickens) were studied for 7 wk. The birds were housed in furnished cages with 10 birds per cage for each strain. At 32-wk of age, the birds in each strain were divided into normal (NK), deviated (DK), and fractured (FK) hens according to the keel bone status. Ten birds in each keel bone status per strain were subsequently selected to collect blood for the determination of stress and fear-related indicators, including corticosterone, serotonin, interleukin-1β, and interleukin-6, and measure fear responses, including novel object test (NOT), human approach test (HAT), and tonic immobility (TI) test. The results showed that egg production was lower and the incidence of keel bone fractures was higher in Lindian chickens than in Hy-line Brown hens (P < 0.05). Lindian chickens showed a significantly increased whole blood serotonin content, NOT-latency, HAT-score, and TI induction times (P < 0.05) and decreased serum interleukin-6 content and TI-duration (P < 0.05) compared with Hy-line Brown hens. Additionally, FK hens had significantly elevated whole blood corticosterone, serum interleukin-1β and interleukin-6 levels, TI-duration, and NOT-latency (P < 0.05), and a reduced whole blood serotonin content (P < 0.05) compared with NK and DK hens. Our results indicated that KBD affected stress and fear responses, and this impact was mainly reflected by FK hens compared with NK and DK hens. We suggest that keel bone fractures are the main factor impairing hen welfare. Besides, the incidence of keel bone fractures and stress and fear responses of Lindian chickens are more severe than Hy-line Brown laying hens, indicating that the strain type can affect the health and welfare of laying hens.
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Affiliation(s)
- Haidong Wei
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Yanru Feng
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Susu Ding
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Haoyang Nian
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Hanlin Yu
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Qian Zhao
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
| | - Jun Bao
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China.,Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin 150030, China
| | - Runxiang Zhang
- College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China.,Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin 150030, China
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MacLellan A, Fureix C, Polanco A, Mason G. Can animals develop depression? An overview and assessment of ‘depression-like’ states. BEHAVIOUR 2021. [DOI: 10.1163/1568539x-bja10132] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Describing certain animal behaviours as ‘depression-like’ or ‘depressive’ has become common across several fields of research. These typically involve unusually low activity or unresponsiveness and/or reduced interest in pleasure (anhedonia). While the term ‘depression-like’ carefully avoids directly claiming that animals are depressed, this narrative review asks whether stronger conclusions can be legitimate, with animals developing the clinical disorder as seen in humans (cf., DSM-V/ICD-10). Here, we examine evidence from animal models of depression (especially chronically stressed rats) and animals experiencing poor welfare in conventional captive conditions (e.g., laboratory mice and production pigs in barren environments). We find troubling evidence that animals are indeed capable of experiencing clinical depression, but demonstrate that a true diagnosis has yet to be confirmed in any case. We thus highlight the importance of investigating the co-occurrence of depressive criteria and discuss the potential welfare and ethical implications of animal depression.
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Affiliation(s)
- Aileen MacLellan
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1
| | - Carole Fureix
- Bristol Veterinary School, University of Bristol, Langford, UK
| | - Andrea Polanco
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1
| | - Georgia Mason
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1
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9
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Keel Bone Damage in Laying Hens-Its Relation to Bone Mineral Density, Body Growth Rate and Laying Performance. Animals (Basel) 2021; 11:ani11061546. [PMID: 34070496 PMCID: PMC8228274 DOI: 10.3390/ani11061546] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/18/2021] [Accepted: 05/20/2021] [Indexed: 02/04/2023] Open
Abstract
Simple Summary Keel bone damage is an important welfare issue for laying hens. Four lines of laying hens, differing in phylogenetic origin and laying rate kept in single cages or a floor housing system were weighed and deformities of the keel bone were evaluated regularly between 15 and 69 weeks of age. Deformities, fractures and the bone mineral density of the keels were assessed after hens were euthanized. We analyzed the relationship between bone mineral density and total egg number as well as body growth. Hens kept in cages showed more deformities, but fewer fractures and a lower bone mineral density of the keel bone than did floor-housed hens. Keel bones of white-egg layers had a lower mineral density and were more often deformed compared with brown-egg layers. Keel bones were more often broken in hens of the layer lines with a high laying rate compared to the lines with a moderate laying rate. Laying rate and adult body weight had an effect on the keel bone mineral density. The study contributes to the understanding of factors causing keel bone damage in laying hens. It showed that the bone mineral density greatly affects keel bone deformities. Abstract Keel bone damage is an important animal welfare problem in laying hens. Two generations of four layer lines, differing in phylogenetic background and performance level and kept in single cages or floor pens were weighed and scored for keel bone deformities (KBD) during the laying period. KBD, keel bone fractures (KBF) and the bone mineral density (BMD) of the keels were assessed post mortem. For BMD, relationships to laying performance and body growth were estimated. Caged hens showed more deformities, but fewer fractures and a lower BMD of the keel bone than floor-housed hens. White-egg layers had a lower BMD (0.140–0.165 g/cm2) and more KBD than brown-egg layers (0.179–0.184 g/cm2). KBF occurred more often in the high-performing lines than the moderate-performing ones. However, in the high-performing lines, BMD was positively related to total egg number from 18 to 29 weeks of age. The adult body weight derived from fitted growth curves (Gompertz function) had a significant effect (p < 0.001) on keels’ BMD. The study contributes to the understanding of predisposing factors for keel bone damage in laying hens. It showed that the growth rate has a rather subordinate effect on keels’ BMD, while the BMD itself greatly affects KBD.
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Wolc A, Settar P, Fulton JE, Arango J, Rowland K, Lubritz D, Dekkers JCM. Heritability of perching behavior and its genetic relationship with incidence of floor eggs in Rhode Island Red chickens. Genet Sel Evol 2021; 53:38. [PMID: 33882840 PMCID: PMC8059289 DOI: 10.1186/s12711-021-00630-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 04/07/2021] [Indexed: 11/11/2022] Open
Abstract
Background As cage-free production systems become increasingly popular, behavioral traits such as nesting behavior and temperament have become more important. The objective of this study was to estimate heritabilities for frequency of perching and proportion of floor eggs and their genetic correlation in two Rhode Island Red lines. Results The percent of hens observed perching tended to increase and the proportion of eggs laid on the floor tended to decrease as the test progressed. This suggests the ability of hens to learn to use nests and perches. Under the bivariate repeatability model, estimates of heritability in the two lines were 0.22 ± 0.04 and 0.07 ± 0.05 for the percent of hens perching, and 0.52 ± 0.05 and 0.45 ± 0.05 for the percent of floor eggs. Estimates of the genetic correlation between perching and floor eggs were − 0.26 ± 0.14 and − 0.19 ± 0.27 for the two lines, suggesting that, genetically, there was some tendency for hens that better use perches to also use nests; but the phenotypic correlation was close to zero. Random regression models indicated the presence of a genetic component for learning ability. Conclusions In conclusion, perching and tendency to lay floor eggs were shown to be a learned behavior, which stresses the importance of proper management and training of pullets and young hens. A significant genetic component was found, confirming the possibility to improve nesting behavior for cage-free systems through genetic selection.
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Affiliation(s)
- Anna Wolc
- Department of Animal Science, Iowa State University, 806 Stange Road, 239E Kildee Hall, Ames, IA, 50010, USA. .,Hy-Line International, 2583 240th Street, Dallas Center, IA, 50063, USA.
| | - Petek Settar
- Hy-Line International, 2583 240th Street, Dallas Center, IA, 50063, USA
| | - Janet E Fulton
- Hy-Line International, 2583 240th Street, Dallas Center, IA, 50063, USA
| | - Jesus Arango
- Hy-Line International, 2583 240th Street, Dallas Center, IA, 50063, USA
| | - Kaylee Rowland
- Hy-Line International, 2583 240th Street, Dallas Center, IA, 50063, USA
| | - Danny Lubritz
- Hy-Line International, 2583 240th Street, Dallas Center, IA, 50063, USA
| | - Jack C M Dekkers
- Department of Animal Science, Iowa State University, 806 Stange Road, 239E Kildee Hall, Ames, IA, 50010, USA
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11
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Wei H, Pan L, Li C, Zhao P, Li J, Zhang R, Bao J. Dietary Soybean Oil Supplementation Affects Keel Bone Characters and Daily Feed Intake but Not Egg Production and Quality in Laying Hens Housed in Furnished Cages. Front Vet Sci 2021; 8:657585. [PMID: 33816591 PMCID: PMC8017272 DOI: 10.3389/fvets.2021.657585] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Accepted: 03/03/2021] [Indexed: 11/13/2022] Open
Abstract
To evaluate dietary soybean oil supplementation on production performance, egg quality, and keel bone health in laying hens. Two hundred and four laying hens at 20 weeks of age (WOA) were distributed into 12 cages containing 17 birds each. Birds were either fed a commercial diet (control group, CON) or a diet supplemented with 3% of soybean oil (SO group). Experiments lasted 17 weeks. Body weight, daily feed intake, production performance and egg quality were measured at 25, 29, 33, and 37 WOA. Birds were subsequently assessed for keel bone status by palpation, and keel was excised to measure bone length, microstructure, bone mineral density (BMD), elements contents, and the expression of osteoprotegerin (OPG), receptor activator of nuclear factor kappa-B ligand (RANKL), collagen type II alpha 1 (COL2α1), periostin (POSTN), and sclerostin (SOST). The results showed that dietary SO supplementation did not affect production performance and egg quality (P > 0.05), but improved body weight of hens at 29 and 37 WOA (P < 0.05), and decreased daily feed intake at 33 and 37 WOA (P < 0.05). Incidence of keel bone damage (especially fracture) was higher in hens of SO group. Keel bone length in birds of SO group was significantly decreased compared to CON (P < 0.05). Keel bone of supplemented hens showed increased trabecular separation at 29 WOA and higher levels of V, Mn, Fe, Se, and Ba at 33 WOA (P < 0.05). Moreover, decreased BMD, trabecular number and thickness were observed in keel bone of laying hens receiving supplementation at 29 and 37 WOA (P < 0.05); decreased levels of Li, Ca, Hg, and TI at 33 WOA and trabecular thickness at 37 WOA (P < 0.05) were also identified. mRNA levels of SOST and RANKL and the ratio of RANKL/OPG mRNA levels were increased in birds fed a SO-supplemented diet (P < 0.05); COL2α1, OPG, and POSTN were downregulated at all sampling points (P < 0.05). Taken together, results indicate that feeding laying hens a diet supplemented with soybean oil can decrease daily feed intake and impair keel bone health but not influence production performance and egg quality.
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Affiliation(s)
- Haidong Wei
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Lei Pan
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Chun Li
- College of Life Science, Northeast Agricultural University, Harbin, China
| | - Peng Zhao
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Jianhong Li
- College of Life Science, Northeast Agricultural University, Harbin, China
| | - Runxiang Zhang
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China.,Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China
| | - Jun Bao
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China.,Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China
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Huang J, Hu Y, Tong X, Zhang L, Yu Z, Zhou Z. Untargeted metabolomics revealed therapeutic mechanisms of icariin on low bone mineral density in older caged laying hens. Food Funct 2021; 11:3201-3212. [PMID: 32211683 DOI: 10.1039/c9fo02882j] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Osteoporosis is a common chronic disease in the elderly population and in some domestic animals. Caged layer osteoporosis (CLO) is a common bone metabolism disease that was recently recommended as an ideal animal model for osteoporosis. This study aimed to investigate the therapeutic effect and mechanism of dietary icariin (ICA), the main bioactive component of the Chinese herb Epimedium, on low bone mineral density (BMD) in older caged laying hens. A total of 216, 54-week-old Lohmann pink-shell laying hens were allocated to three groups, comprising one control group and two treatment groups that were additionally supplied with 0.5 or 2.0 g kg-1 ICA. The results showed that dietary ICA significantly increased the femur BMD by 49.3% and the tibia BMD by 38.9%, improved the microstructure of bone tissue, decreased levels of the bone metabolism index, enhanced serum antioxidant capacity and regulated messenger RNA expression of bone-related genes. ICA-induced differential metabolites were clarified by using untargeted metabolomics assays. Furthermore, correlation analysis between differential metabolites and BMD indicated that eight differential metabolites correlated highly with both femur and tibia BMD, including uridine, taurine, palmitic acid, adrenic acid, fexofenadine, lysoPC(18 : 1), lysoPE(20 : 3/0 : 0) and 3-acetyl-11-keto-beta-boswellic acid. ICA mainly perturbed pyrimidine metabolism, taurine metabolism and lipid metabolism, which led to increased BMD in older caged laying hens. These findings revealed underlying therapeutic mechanisms of dietary ICA on low BMD, and provided reference metabolites for the early diagnosis of osteoporosis.
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Affiliation(s)
- Jie Huang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China. and The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Yanping Hu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China. and The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Xiaofeng Tong
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China. and The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Lei Zhang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China. and The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhengwang Yu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China. and The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhongxin Zhou
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China. and The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
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Singh M, Groves PJ. Welfare implications for barn (and aviary) egg production systems. ANIMAL PRODUCTION SCIENCE 2021. [DOI: 10.1071/an19634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Barn production systems in Australia are either an indoor-housing floor system or an aviary system with multilevel structures, equipped with nesting boxes, perches and feeding and watering systems. These systems offer hens the freedom of movement and an opportunity to display a repertoire of favourable behaviours as well as interact with complex housing elements as compared with caged systems. However, the system can create prospects for the hens to express detrimental behaviours such as feather pecking and cannibalism. Other aspects of welfare that may be compromised when compared with cage systems include incidence of fractures and injuries during navigation of hens among elements of housing that may result in collision or falls. Barn production systems may have an advantage over free-range production systems in relation to the protection they offer from predators and predator stress, and diseases and parasites that can be contracted from range areas. Barn systems also offer better biosecurity due to lack of direct access to wild birds and their faeces. The aim of the present review is to assess the welfare status of birds housed in barn (and aviary) production systems, while considering husbandry factors that affect welfare outcomes, the health and disease implications and sustainability. To maintain a high welfare outcome in barn production systems, it is important to keep the enclosed environmental conditions optimum by managing air quality, ventilation and lighting within sheds. Sustainability of these production systems depends on consumer preference, cost of production, environmental footprint and suitable genetics of hens.
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Edwards LE, Hemsworth PH. The impact of management, husbandry and stockperson decisions on the welfare of laying hens in Australia. ANIMAL PRODUCTION SCIENCE 2021. [DOI: 10.1071/an19664] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The present review examines the impact of management and husbandry decisions on the welfare of laying hens in Australia. The literature on many of these aspects is lacking for the Australian egg industry, and, indeed, for the egg industry in general. Management decisions that can affect hen welfare relate to the initial farm design, husbandry routines, and staff selection and training. As modern laying houses represent a considerable financial investment, the decisions made during the design phase are likely to affect both the hens and stockpeople for substantial periods. Hens in cage systems may benefit from fewer tiers and greater space allowances. In non-cage systems, the brown genotypes used in the Australian egg industry may benefit from lower structures that accommodate their heavier and less agile bodies. Keel fractures can be reduced by improving the skeletal health and spatial cognition of laying hens during the rearing period, in addition to minimising the distances they need to jump when navigating aviary structures. The addition of a wintergarden to fixed free-range systems appears to be beneficial. Housing hens in mobile units on free-range farms may challenge their welfare, particularly in relation to heat stress. There is also room for improvement in biosecurity practices and health monitoring of hens, as these appear to be lacking at some farms. The current strains of hen used in free-range systems may not be best suited to these conditions, on the basis of their body condition and flock uniformity. Feed quality may also need to be monitored for quality assurance and optimal hen nutrition. Hen welfare during depopulation can be improved through staff training and by reducing staff fatigue. Euthanising spent hens on farm offers welfare benefits over transporting spent hens to an abattoir. Both hen welfare and working conditions for stock people should be considered when designing laying houses to provide suitable conditions for both hens and stockpeople. This will help improve the job satisfaction of stockpeople, which may translate into better care for the hens and may aid in retaining quality staff. Stockpeople must be recognised as vital contributors to hen welfare in the egg industry, and it is important for the egg industry to continue to attract, train and retain skilled stockpeople to ensure that they enjoy their job and are motivated to apply best-practice care for their flocks. Promoting the animal-care aspect of stockmanship in combination with a supportive managerial environment with optimal working conditions may increase the attractiveness of the egg industry as a place to work.
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Campbell DLM. Skeletal health of layers across all housing systems and future research directions for Australia. ANIMAL PRODUCTION SCIENCE 2021. [DOI: 10.1071/an19578] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Modern laying hens have been selected for an astounding rate of egg production, but the physiological calcium demand takes a significant toll on their skeletal health. Bones can be assessed both in vivo and ex vivo, using a combination of different structural and mechanical analysis methods. Typically, the properties of leg, wing and keel bones are measured. Conventional caged layers are restricted in movement, which imbalances structural bone resorption and new bone formation, resulting in osteoporosis. Hens within alternative housing systems have opportunities to exercise for strengthening bones, but they can also suffer from higher rates of keel fractures and/or deviations that are likely to have resulted from collisions or pressure force. Limited research has been conducted within Australian commercial housing systems to assess hen skeletal health, including prevalence of keel damage across different system types. Research conducted on both brown and white hen strains approximately within the past decade internationally (2009 onward) has shown that skeletal health is impaired across all housing systems. Keel-bone damage is of specific concern as it occurs at high rates, particularly in multi-tiered systems, is painful, can alter hen behaviour, and reduce both production and egg quality. Management strategies such as the provision of ramps to access perches and tiers can reduce the incidence of keel-bone damage to a degree. Bone strength can be improved through exercise opportunities, particularly when available during pullet rearing. Genetic selection for high bone strength may be necessary for hens to adequately adapt to loose-housed systems, but the best strategy for improving skeletal health is likely to be multifactorial.
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Rufener C, Makagon MM. Keel bone fractures in laying hens: a systematic review of prevalence across age, housing systems, and strains. J Anim Sci 2020; 98:S36-S51. [PMID: 32810250 PMCID: PMC7433929 DOI: 10.1093/jas/skaa145] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 06/16/2020] [Indexed: 12/24/2022] Open
Affiliation(s)
- Christina Rufener
- Department of Animal Science, Center for Animal Welfare, University of California, Davis, CA
| | - Maja M Makagon
- Department of Animal Science, Center for Animal Welfare, University of California, Davis, CA
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Huang J, Tong XF, Yu ZW, Hu YP, Zhang L, Liu Y, Zhou ZX. Dietary supplementation of total flavonoids from Rhizoma Drynariae improves bone health in older caged laying hens. Poult Sci 2020; 99:5047-5054. [PMID: 32988541 PMCID: PMC7598317 DOI: 10.1016/j.psj.2020.06.057] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 05/13/2020] [Accepted: 06/11/2020] [Indexed: 01/23/2023] Open
Abstract
Caged layer osteoporosis (CLO) is a common bone metabolism diseases and poses a great threat to the production of laying hens. So far, there is no effective nutrition intervention to prevent CLO. The objective of this study was to evaluate the effects of dietary total flavonoids from Rhizoma Drynariae (TFRD), a Chinese herbal, on bone health, egg quality, and serum antioxidant capacity of caged laying hens. A total of two hundred sixteen, 54-wk-old Lohmann Pink-shell laying hens at were allocated to 3 groups with 6 replicates of 12 hens per replicate. The control group was fed a basal diet (BD) and 2 treatment groups additionally supplied with 0.5 or 2.0 g/kg TFRD, respectively. Results showed that supplying 2.0 g/kg TFRD enhanced the activities of serum total antioxidant capacity (P < 0.01) and glutathione peroxidase (P < 0.05) and had higher femur and tibia bone mineral density (both P < 0.05) compared with the control group. Dietary 2.0 g/kg TFRD also reduced the activities of serum alkaline phosphatase (P < 0.01), tartrate resistant acid phosphatase (P < 0.01), and the contents of osteocalcin (P < 0.01). Furthermore, tibia histomorphology observation showed that the microstructure of bone tissue was improved after TFRD treatment. Egg quality was not affected by TFRD while the egg weight significantly increased (P < 0.01). These findings suggested that TFRD has beneficial effects on bone health in older caged laying hens.
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Affiliation(s)
- J Huang
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - X F Tong
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Z W Yu
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Y P Hu
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - L Zhang
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Y Liu
- Experimental Teaching Center, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Z X Zhou
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Department of Animal Nutrition and Feed Science, College of Animal Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.
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Petek M, Çavuşoğlu E. Welfare Assessment of Two Free-range Laying Hen Flocks in Turkey. J APPL ANIM WELF SCI 2020; 24:56-63. [PMID: 32643954 DOI: 10.1080/10888705.2020.1790368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This study aimed to determine the prevalence of keel bone deviations and feather damage of laying hens in two different free-range housing systems under commercial conditions. Both of the free-range systems had an indoor barn and an outdoor range area. The floor of the indoor barn consisted of litter and either perches (litter and perch, LP) or slats (litter and slats, LS). The hens of both flocks were raised under identical conditions in the same house during the rearing period and then divided and transferred to two different free-range housing systems for the laying period. Examinations were conducted on the flocks at the end of the production cycle. Hens from the LP group had a greater prevalence of keel bone deviation and feather damage compared to hens from the LS group. The highest percentage of severe feather damage was found in the back and tail body regions in both flocks. The findings of this study are based upon the evaluation of two Turkish laying flocks. Therefore further research with more replicates of these treatments is needed to reach a general conclusion.
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Affiliation(s)
- Metin Petek
- Department of Animal Sciences, Faculty of Veterinary Medicine, University of Bursa Uludag, Turkey
| | - Enver Çavuşoğlu
- Department of Animal Sciences, Faculty of Veterinary Medicine, University of Bursa Uludag, Turkey
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Tixier-Boichard M. From the jungle fowl to highly performing chickens: are we reaching limits? WORLD POULTRY SCI J 2020. [DOI: 10.1080/00439339.2020.1729676] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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