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Midshaft femur bone density by peripheral quantitative computed tomography of hens fed a normal layer ration or an alfalfa-based molt diet for a 9-d molt period. PC = pretrial control; FF = fully fed 100% layer ration; FW = feed withdrawal; A90 = 90% alfalfa:10% layer ration; A80 = 80% alfalfa:20% layer ration; A70 = 70% alfalfa:30% layer ration. a,b Means ± SE with different letters differ (P < 0.05).
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A study was conducted to evaluate the effects of alfalfa-based molt diets on molting performance and bone qualities. A total of 36 Single Comb White Leghorn hens were used for the study. There were 6 treatments: pretrial control (PC), fully fed (FF), feed withdrawal (FW), 90% alfalfa:10% layer ration (A90), 80% alfalfa:20% layer ration (A80), and 7...
Citations
... Bone ash parameters were assessed following the methodologies outlined by Zhang and Coon (1997) and Kim et al. (2004;2007). Briefly, the bones were immersed in water at room temperature (25°C) and subsequently weighed. ...
An experiment was conducted to evaluate the effects of phytase in calcium (Ca) and available phosphorous (avP)-reduced diet on growth performance, body composition, bone health, and intestinal integrity of broilers challenged with Eimeria maxima and Eimeria acervulina. A total of 672 14-day-old male broilers were allocated to a 2 × 4 factorial arrangement with 6 replicates per treatment and 14 birds per replicate. Two factors were Eimeria challenge and 4 dietary treatments: 1) a positive control (PC; 0.84% Ca and 0.42% avP); 2) a negative control (NC; 0.74% Ca and 0.27% avP); 3) NC + 500 FTU/Kg of phytase (NC + 500PHY); and 4) NC + 1,500 FTU/Kg of phytase (NC + 1500PHY). On d 14, birds in the Eimeria-challenged groups received a solution containing 15,000 sporulated oocysts of E. maxima and 75,000 sporulated oocysts of E. acervulina via oral gavage. At 5 d postinoculation (DPI), the challenged birds showed a higher (P < 0.01) FITC-d level than the unchallenged birds. While the permeability of the NC group did not differ from the PC group, the phytase supplementation groups (NC + 500PHY and NC + 1500PHY) showed lower (P < 0.05) serum FITC-d levels compared to the NC group. Interaction effects (P < 0.05) of Eimeria challenge and dietary treatments on feed intake (FI), mucin-2 (MUC2) gene expression, bone ash concentration, and mineral apposition rate (MAR) were observed. On 0 to 6 and 0 to 9 DPI, Eimeria challenge decreased (P < 0.01) body weight (BW), body weight gain (BWG), FI, bone mineral density (BMD), bone mineral content (BMC), bone area, fat free bone weight (FFBW), bone ash weight, bone ash percentage and bone ash concentration; and it showed a higher FCR (P < 0.01) compared to the unchallenged group. The reduction Ca and avP in the diet (NC) did not exert adverse effects on all parameters in birds, and supplementing phytase at levels of 500 or 1,500 FTU/Kg improved body composition, bone mineralization, and intestinal permeability, with the higher dose of 1,500 FTU/Kg showing more pronounced enhancements. There was an observed increase in FI (P < 0.01) when phytase was supplemented at 1,500 FTU/Kg during 0 to 6 DPI. In conclusion, results from the current study suggest that dietary nutrients, such as Ca and avP, can be moderately reduced with the supplementation of phytase, particularly in birds infected with Eimeria spp., which has the potential to save feed cost without compromising growth performance, bone health, and intestinal integrity of broilers.
... A robust skeletal structure is also vital for minimizing the risk of leg disorders and fractures (Kiero nczyk et al., 2017). Maintaining optimal bone health in broilers is thus essential for ensuring the welfare and performance of the broiler birds (Kim et al., 2007;Kolakshyapati et al., 2019). ...
Despite the acknowledged significance of nutrition in bone development, effects of methionine (Met) and cysteine (Cys) on bone quality remain under-researched, particularly during Eimeria challenge. We investigated the effects of different supplemental Met to Cys ratios (MCR) on bone quality of broilers under Eimeria challenge. A total of 720 fourteen-day old Cobb500 broilers were allocated into a 5 × 2 factorial arrangement. Five diets with Met and Cys supplemented at MCR of 100:0, 75:25, 50:50, 25:75, and 0:100 were fed to the birds with or without Eimeria challenge. Body composition was measured by dual energy x-ray absorptiometry, and the femur bone characteristics were assessed by microtomography. Data were analyzed by two-way ANOVA and orthogonal polynomial contrast. The results reaffirmed the detrimental effects of Eimeria challenge on bone quality. On 9 d post inoculation (DPI), significant interaction effects were found for whole body bone mineral content (BMC), lean tissue weight, and body weight (P < 0.05); in the nonchallenged group (NCG), these parameters linearly decreased as MCR decreased (P < 0.05). In the challenged group (CG), body weight and lean tissue weight were unaffected by MCR, and BMC linearly increased as MCR decreased (P < 0.05). For the cortical bone of femoral metaphysis on 6 DPI, bone mineral density (BMD) linearly increased as MCR decreased (P < 0.05). Bone volume to tissue volume ratio (BV/TV) in the CG linearly increased as MCR decreased (P < 0.05). On 9 DPI, BMC and TV linearly increased as MCR decreased (P < 0.05) in the NCG. BMD and BV/TV changed quadratically as MCR decreased (P < 0.05). For the trabecular bone of femoral metaphysis on 9 DPI, BV/TV, and trabecular number linearly increased as MCR decreased (P < 0.05) in the NCG. For the femoral diaphysis, BV, TV, BMC on 6 DPI, and BMD on 9 DPI linearly increased as MCR decreased (P < 0.05). In conclusion, this study showed that both Eimeria challenge and varying supplemental MCR could influence bone quality of broilers.
... Using a water dropper pipette (Thermo Fisher Scientific, Waltham, MA), the final samples were loaded in McMaster chambers (Jorgensen Laboratories, Loveland, CO), and the total oocysts were counted, and the data were calculated as oocysts per gram using formula as shown by Yadav et al. (2020). Bone Ash On d 20 (6 dpi) and d 23 (9 dpi), 1 bird from each pen was euthanized to collect tibia for measuring bone volume (BV), fat free dry bone weight (FFBW), bone ash percentage (Ash%), and bone ash concentration (BC) were measured according to the methods described by Kim et al. (2004Kim et al. ( , 2007. Bones were dried at 100°C for 24 h followed by 76 h refluxing in a Soxhlet apparatus with hexane. ...
This study evaluated the effects of 25-hydroxycholecalciferol (25-OHD) on performance, gut health, and bone quality of broilers fed with reduced calcium (Ca) and phosphorus (P) diet during Eimeria spp. challenge. A total of 576 fourteen-day-old Cobb 500 male chicks were randomly distributed in a 2 × 2 × 2 factorial arrangement, with 6 replicates of 12 birds each. The main factors were 25-OHD level (0 or 3,000 IU/kg of feed), mineral level (0.84% of Ca/0.42% of P, the levels recommended for the grower phase (NOR) or 0.64% of Ca/0.22% of P (RED), and mid-high mixed Eimeria challenge or nonchallenge. 25-OHD improved phosphorus retention (P = 0.019), bone ash weight (P = 0.04), cortical bone trabecular connectivity (P = 0.043) during coccidiosis. For birds fed with reduced mineral levels, 25-OHD supplementation increased bone ash weight (P = 0.04). However, 25-OHD did not improve bone ash weight when birds were challenged and fed with reduced mineral levels. The dietary 3,000 IU of 25-OHD supplementation did not improve performance or gut morphology but support bone health during coccidiosis. Future investigations are needed for better understand 25-OHD role on bone microarchitecture and oxidative metabolism during coccidiosis.
... Skeletal health is of utmost importance in laying hens, as their long bones in particular serve as a labile source of calcium for both egg production and providing mechanical support for their entire body. Additionally, skeletal disorders are often associated with chronic pain in pullets or laying hens, limiting their access to feed, thus negatively affecting their welfare (Webster, 2004;Kim et al., 2007aKim et al., , 2007bKim et al., , 2012Riber et al., 2018). To date, no studies have examined the effects of coccidiosis on the skeletal health of laying hen pullets and this challenge model will help to understand the effect of coccidiosis on the skeletal health of laying hen pullets. ...
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.
... The bone quality of birds not only affects the laying performance and egg quality, but is also related to the welfare of laying hens [37,38]. The modern layers have a high incidence of osteoporosis at the later laying period [39,40]. Bone growth and development are concentrated in the early stages, so it is necessary to improve bone quality as much as possible during this stage. ...
This experiment was conducted to explore the effect of long-term supplementation of 25-hydroxyvitamin D3 (25-OHD) as a vitamin D3 (VD3) substitute on performance, bone traits, and egg quality of laying hens from 1 day to 72 weeks of age. In total, 900 one-day-old Lohman pullets were randomly allotted into three dietary groups (three treatments × 15 replicates × 20 birds per replicate): VD3 2800 IU/kg; 25-OHD 69 μg/kg; 25-OHD 125 μg/kg. At the end of the 20th w, five replicates from each group were selected to feed on the same vitamin D diets, as used during the rearing stage (1–20 w) until 72 w. The result showed that the 25-OHD 125 μg/kg treatment had the lowest average daily feed intake (ADFI) at 1–8 or 1–19 w, body weight at 8 w, body weight gain between 1 and 8 w and shank length at 4 w (p < 0.05). The 25-OHD 125 μg/kg treatment had a lower shank length at 7 w, compared with the 25-OHD 69 μg/kg treatment. The shank length of the birds in each treatment reached the maximum (about 103 mm) at about 18 w of age. For the bone traits, the 25-OHD 125 μg/kg treatment had the lowest femur bone diameter at 20 w (p < 0.001) and femur bone plumpness at 20 w (p = 0.002). The 25-OHD 125 μg/kg treatment had a lower tibia strength at 10 w (p = 0.023) and keel length at 10 w (p = 0.046), compared with the 25-OHD 69 μg/kg treatment. However, both 25-OHD 69 and 125 μg/kg treatments had a greater femur strength at 72 w (p = 0.006), compared with the VD3 2800 IU/kg treatment. No difference in laying performance was observed among all treatments. The overall (21–72 w) ADFI in the 25-OHD 125 μg/kg treatment was significantly lower than that in the 25-OHD 69 μg/kg treatment (p = 0.030). At 60 w, the 25-OHD 125 μg/kg treatment had a lower eggshell thickness (p = 0.012) and proportion of eggshell (p = 0.022), compared with the 25-OHD 69 μg/kg treatment. No significant differences in egg quality parameters were observed at 50 and 70 w among treatments. In general, supplementary 2800 IU/kg doses of VD3 at the early stage were sufficient to maintain the bone quality and growth and development of pullets. Feeding birds at a higher 25-OHD level (125 μg/kg) resulted in the reduced ADFI and growth at the rearing period, but the long-term supplementation of 25-OHD as a VD3 substitute improved the bone quality in the late laying period.
... This finding, combined with the lack of changes in cortical bone thickness during the persistent laying cycle, suggests a lack of osteoporosis in the diaphysis of the tibia, as defined by Whitehead and Fleming (2000). While this contrasts with a previous report showing a loss of structural bone, especially the overall cBMD, from the initiation of lay to the end of the cycle regardless of strain , a study by Kim et al. (2007), using a more contemporary strain reported no changes in cBMD regardless of laying status. This may be explained by the moderate heritability of BMD reported in hens (h 2 = 0.35 to 0.40; Bishop et al., 2000;Guo et al., 2017) and its possible association with body size and egg production (Rennie et al., 1997;Fleming et al., 2004), as both of these traits are part of the current breeding programs. ...
Decades of intensive genetic selection in commercial layers has resulted in earlier maturation, while sustaining high production rates to 100 weeks of age (woa). To support eggshell formation while maintaining a healthy skeletal frame, substantial adaptations of calcium metabolism in the hen are necessary. Thus, skeletal growth, bone density, and egg quality were compared in three strains of layers, with the Lohmann LSL-lite as the current commercial strain, the heritage Shaver white leghorn as the mid-2000s strain, and the white-leghorn derived Smoky Joes as the non-selected 1960s strain. Tibia and Femur (n = 4/strain) were collected at 12, 17, 20, 25, 45, 60, 75 and 100 woa. Bones were measured and weighed, with bone mineral density assessed within medullary (mBMD) and cortical (cBMD) regions of the tibia using micro-Computed Tomography. Egg analyses including weight, eggshell thickness (EST) and eggshell breaking strength (EBS), were conducted throughout lay. Blood samples were collected to measure plasma calcium immediately prior to lay (18 woa) and periodically throughout the laying cycle. Femur and tibia weight, or size, did not increase beyond 12 woa, indicating that all hens reached maximum skeletal size by this time. An interaction (P = 0.005) was observed between strain and tibia mBMD, as all three strains demonstrated an accumulation of medullary bone from 12 to 100 woa. Regarding egg weight, while Lohmann hen eggs displayed the highest quality at 26 woa, an elevation in egg weight in Lohmann and Shaver hens (P < 0.001) resulted in a decline in EST and EBS over time (P < 0.01). Yet, at 100 woa, no strain differed in EST or EBS, despite larger variations in cumulative egg numbers (P < 0.001). Plasma calcium levels were significantly elevated between the immature state and peak of lay but remained unchanged throughout lay in all strains. In conclusion, our results show that although genetic selection of layer hens resulted in tremendous improvement in productivity, no detrimental effects on cBMD or mBMD were observed throughout an extended laying period up to 100 woa.
... For laying hens, with the increase of the laying rate and the prolongation of the laying cycle, the number of mineralized structural bones of hens will decrease gradually; this leads to an increase in the incidence of osteoporosis [30,31]. Therefore, it is necessary to improve the bone quality as much as possible during the growth and development stage of bone. ...
A study was conducted to evaluate the effect of 25-hydroxyvitamin D3 (25-OHD) with different levels of vitamin D3 (VD3) during the rearing period (1–20 weeks) on laying hen performance, bone quality, and eggshell quality. A total of four hundred 1-day-old Lohman pullets were randomly allotted into a 2 × 2 factorial design with 2 levels of dietary VD3 (300 and 2800 IU/kg) and 2 levels of dietary 25-OHD (0 and 56 μg/kg). Each treatment had five replicates of 20 hens each. Increasing the dietary VD3 level (2800 vs. 300 IU/kg) tended to increase body weight uniformity (0.05 < p < 0.1) at 8 weeks. Dietary VD3 levels and supplementation of 25-OHD during the growing period (1–20 weeks) did not improve the laying performance and eggshell quality (eggshell strength, eggshell thickness, and eggshell relative weight) during the laying period (p > 0.05). Compared with the 300 IU/kg VD3 group, the 2800 IU/kg VD3 group showed higher serum calcium concentration and keel length at 10 weeks (p < 0.05). The addition of 25-OHD significantly increased serum calcium and 25-OHD concentration at 10 and 20 weeks and keel calcified rate at 20 weeks (p < 0.05). Increasing dietary VD3 level (2800 vs. 300 IU/kg) increased tibia ash and phosphorus content at 10 weeks, tibia strength at 72 weeks (p < 0.05), and tended to increase tibia ash content at 72 weeks, tibia calcium content and tibia strength at 20 weeks (0.05 < p < 0.1). Dietary supplementation with 25-OHD increased tibia ash content at 10 weeks, tibia calcium content and tibia strength at 20 weeks (p < 0.05), and tended to increase tibia ash content at 72 weeks (0.05 < p < 0.1). Overall, the results gathered in this study indicate that dietary supplementation of high levels of VD3 and 25-OHD during the growing period improved the tibia quality of laying hens during the early and later laying period, but had no effect on laying performance and eggshell quality during the laying period.
... In fact, skeletal quality has been an important welfare, health and economic issue in poultry production. Structural bone loss related to osteoporosis may be the major skeletal problem in laying poultry (Kim et al., 2007), which could cause a high incidence of fractures at various sites of the skeleton, resulting in an average of 34% of processed birds exhibiting freshly broken bones (Whitehead and Fleming, 2000). In fact, superior bone quality of laying poultry can be ascribed to 2 factors: more structural bone formation during the growth phase and less bone loss during the laying period (Whitehead, 2004). ...
We investigated the effect of photoperiod on eggshell quality, bone quality characteristics and bone metabolism related enzymes and factors in laying ducks. After adaption, 300 Jinding laying ducks (252-d-old) were randomly divided into 5 treatments, receiving 12L (hours of light):12D (hours of darkness), 14L:10D, 16L:8D, 18L:6D or 20L:4D, respectively. Each group had 6 replicates of 10 birds each. The feeding experiment lasted 8 wks. Compared with 12L:12D, the higher values of eggshell breaking strength occurred in ≥ 18 h photoperiods at the end of 6 wk, and in ≥ 16 h photoperiods at the end of 4 wk, with the common highest values in 18 h photoperiod (P ˂ 0.05). Besides, 18L:6D had higher values of ultimate load Fu and cortical cross-sectional area A in tibia, femur and ulna (P ˂ 0.05), compared with 12L:12D. The higher values of proximal bone mineral content (BMC; tibia), distal BMC (ulna), total Ca (tibia) and cortical volumetric bone mineral density (vBMC; tibia and ulna) were observed in 16L:8D and 18L:6D treatments (P ˂ 0.05). Meanwhile, 18 h photoperiod group had the higher proximal BMC (femur) and total Ca in ulna (P ˂ 0.05). In serum, compared with 12L:12D group, the higher ALP activity occurred in ≥ 16 h photoperiods (0:00 and 18:00), with the highest values in 18L:6D treatment (P ˂ 0.05); the higher values of TGF-β (6:00) and OC (6:00 and 18:00) were simultaneously observed in 18 h photoperiod (P ˂ 0.05). Moreover, values of trACP activity, TNF-α and IL-6 contents decreased in ≥ 18 h photoperiods at 0:00 (P ˂ 0.05), compared with 12L:12D group. To sum up, an appropriate photoperiod could improve eggshell quality, bone strength and mineral content through increasing osteogenesis during the light time and decreasing resorption activity during the dark, and 18 h is an adequate photoperiod for the eggshell and bone quality of laying ducks.
... Many relevant bone and egg characteristics are known to have an important genetic component that can be used in genetically assisted selection programs aimed at improving bone and eggshell quality [1,[27][28][29]. Also, adequate hen nutrition is crucial to achieve the genetic potential of modern layers while maintaining overall laying hen health [2,[30][31][32]. For instance, as calcium absorption decreases with age, Ca% in the diet needs to be increased at the end of lay [2,33]. ...
(1) Background: Nowadays the industry aims to improve lay persistency for extended cycles (100 weeks or longer) to make egg production more sustainable. However, intensive egg production challenges hen health, inducing severe osteoporosis and the incidence of bone fractures. In this study, the relationship between bone quality and egg production, and/or eggshell quality, was evaluated at the end of an extended laying cycle of 100 weeks, comparing groups of hens with different production and eggshell quality parameters; (2) Methods: Quality parameters of egg (as weight, egg white height), eggshell (as thickness, weight, breaking strength, elasticity and microstructure) and tibiae bone (weight, diameter, cortical thickness, ash weight, breaking strength, medullary bone) were determined; (3) Results: Hens from groups with a high egg production and good eggshell quality have poorer bone quality (lower ash weight and lesser amount of medullary bone). However, Pearson’s correlation analysis shows no clear relationship between bone and egg/eggshell parameters. (4) Conclusions: Bone and egg production/eggshell quality are independent and can be improved separately. Medullary bone has an important contribution to bone mechanical properties, being important to accumulate enough bone medullary bone early in life to maintain skeletal integrity and eggshell quality in old hens.
... Therefore, it is of significance that a large number of GPCRs such as CaSR and taste receptors located in enteroendocrine cells contribute to nutrient sensing. Notably, the structure of female avian bone tissue is distinctive from mammals, which includes cortical, cancellous, and medullary bones (Kim et al., 2007). From morphological results of the tibia tissue, medullary bone was only found in the sexually matured layer (40and 55-week-old) instead of the 19-week-old layer, which was consistent with previous research ( Van de Velde et al., 1985). ...
The extracellular calcium-sensing receptor (CaSR) and vitamin D receptor (VDR) play important roles in regulating calcium mobilization, calcium absorption and calcium homeostasis, and they could be potential therapeutic targets for osteoporosis in laying hens. The present study investigated the molecular distribution of CaSR and VDR and the localization of CaSR in the kidney, proventriculus (true stomach), duodenum, jejunum, ileum, colon, cecum, shell gland and tibia of laying hens at three different laying stages (19, 40 and 55 weeks). The results showed that the relative mRNA abundance of CaSR in the kidney, ileum, proventriculus, duodenum, and colon was higher (P < 0.05) than the other tissues at 40 and 55 weeks. The relative mRNA abundance of CaSR in the tibia was higher (P < 0.05) at 55 weeks than at 40 weeks. However, there were no significant differences in the relative protein abundance of CaSR among all tested tissues at peak production, or in each tissue at the three different laying stages (P > 0.05). The relative mRNA abundance of VDR was higher (P < 0.05) in the small intestine (duodenum, jejunum, and ileum) when compared with other tissues at the three different laying stages. The relative protein abundance of VDR in the duodenum was higher (P < 0.05) than that in the proventriculus, colon, and cecum. There were no significant differences in the VDR expression among the tested tissues at the three different laying stages (P > 0.05). The immunohistochemical results showed that the positive staining was found widely in each tissue. Moreover, different laying stages did not affect the localization of CaSR except for the tibia tissue. In conclusion, similar to VDR, CaSR was widely expressed not only in the gut but also in the tibia and shell gland in laying hens. The expression level of CaSR and VDR in all tested tissues was unchanged at the different laying stages.
