Effect of feeding fermented soybean meal on broiler chickens’ performance: a meta-analysis

Irawan Agung,Ratriyanto Adi,Respati Adib Norma,Ningsih Niati,Fitriastuti Rahma,Suprayogi Wara Pratitis Sabar,Hadi Rendi Fathoni,Setyono Wahyu,Akhirini Novi,Jayanegara Anuraga 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.12

Objective: The present study aimed to quantify the effects of fermented soybean meal (FSBM) on broiler chickens’ performance by employing a meta-analysis approach. Methods: A total of 16 studies were included in the database after being systematically selected using a PRISMA protocol. Hedges’ g effect size was used to quantify pooled standardized mean difference (SMD) using random-effects models at 95% confidence intervals (95% CI). Publication bias among studies was computed with Egger’s test and visualized using funnel plots. Results: Results indicated that dietary FSBM inclusion increased final body weight (BW) (SMD = 0.586, 95% CI: 0.221 to 0.951, p = 0.002) of broiler chickens, particularly in starter period (SMD = 0.691, 95% CL: 0.149 to 1.233, p = 0.013) while in the finisher period, the effect was weaker (SMD = 0.509, 95% CI: 0.015 to 1.004, p = 0.043). Average daily gain (ADG), feed intake (FI), and feed conversion ratio (FCR) were not affected with FSBM inclusion when compared to control. Subgroup analysis revealed that FI increased in starter period (SMD = 0.582, 95% CI: 0.037 to 1.128, p = 0.036). When considering types of microorganism as moderating variables in the subgroup analysis, we found that Aspergillus oryzae, mixed probiotics+bromelain protease, Bacillus subtilis, and Lactobacillus bacteria significantly increased ADG and FI (p<0.01). Additionally, either Bacillus subtilis+protease or Bacillus subtilis alone decreased FCR (p<0.001). However, meta-regression analysis showed that levels of FSBM inclusion had no effects on final BW (p = 0.502), ADG (p = 0.588), FI (p = 0.861), and FCR (p = 0.462). Conclusion: Substituting SBM in broiler chickens’ diet with FSBM improved BW of broiler chickens, especially in the starter period whereas the effects on ADG, FI, and FCR were mostly dependent on microbial strains used for fermentation. Objective: The present study aimed to quantify the effects of fermented soybean meal (FSBM) on broiler chickens’ performance by employing a meta-analysis approach.Methods: A total of 16 studies were included in the database after being systematically selected using a PRISMA protocol. Hedges’ <i>g</i> effect size was used to quantify pooled standardized mean difference (SMD) using random-effects models at 95% confidence intervals (95% CI). Publication bias among studies was computed with Egger’s test and visualized using funnel plots.Results: Results indicated that dietary FSBM inclusion increased final body weight (BW) (SMD = 0.586, 95% CI: 0.221 to 0.951, p = 0.002) of broiler chickens, particularly in starter period (SMD = 0.691, 95% CL: 0.149 to 1.233, p = 0.013) while in the finisher period, the effect was weaker (SMD = 0.509, 95% CI: 0.015 to 1.004, p = 0.043). Average daily gain (ADG), feed intake (FI), and feed conversion ratio (FCR) were not affected with FSBM inclusion when compared to control. Subgroup analysis revealed that FI increased in starter period (SMD = 0.582, 95% CI: 0.037 to 1.128, p = 0.036). When considering types of microorganism as moderating variables in the subgroup analysis, we found that <i>Aspergillus oryzae</i>, mixed probiotics+bromelain protease, <i>Bacillus subtilis</i>, and <i>Lactobacillus</i> bacteria significantly increased ADG and FI (p<0.01). Additionally, either <i>Bacillus subtilis</i>+protease or <i>Bacillus subtilis</i> alone decreased FCR (p<0.001). However, meta-regression analysis showed that levels of FSBM inclusion had no effects on final BW (p = 0.502), ADG (p = 0.588), FI (p = 0.861), and FCR (p = 0.462).Conclusion: Substituting SBM in broiler chickens’ diet with FSBM improved BW of broiler chickens, especially in the starter period whereas the effects on ADG, FI, and FCR were mostly dependent on microbial strains used for fermentation.

산삼배양액 급여에 따른 육계의 생산성 및 질병 저항성 효과

설재원,박재홍,채준석,강형섭,류경선,강춘성,박상열,Seol, Jae-Won,Park, Jae-Hong,Chae, Joon-Seok,Kang, Hyung-Sub,Ryu, Kyeong-Seon,Kang, Chun-Seong,Park, Sang-Youel 대한수의학회 2010 大韓獸醫學會誌 Vol.50 No.2

The large amount of tissue culture medium (TCM), which contains some of the active secretory components of Korean wild ginseng (KWG; Panax ginseng) such as saponins, is usually discarded after harvest of KWG. The present study was aimed to investigate the efficacy of oral administration of the TCM-KWG on growth performance and diseases resistance in broiler chickens. A day old broiler chickens randomized in 6 groups (n = 60/groups) were administered orally with 0, 2, 4, 8, 16 and 32 mL/L TCMKWG through drinking water for 5 weeks and examined the change of weight gain, feed intake and blood components. Also, five weeks old broiler chickens (n = 15/groups) were challenged orally with Salmonella (S.) gallinarum and investigated the mortality in broiler chickens. An average weight gain and feed intake significantly didn't change in TCM-KWG administration groups as compared to control group. The concentration of calcium (Ca), phosphate (Pi) and potassium (K) in serum were increase by TCM-KWG administration in broiler chickens. We also found that oral administration of TCM-KWG through drinking water significantly reduced the mortality in broiler chickens experimentally infected with virulent S. gallinarum. The results of this study indicated that TCM-KWG administration may elevate the resistance on disease and improved the skeleton formation and body homeostasis of chickens, and TCM-KWG can be used as a cost-effective and environmentally alternative additives to control of the disease and growth.

Comparison of the growth performance, nutrient digestibility, fecal microflora, blood profiles, and meat quality of broilers, Korean native chickens and white semi broilers under an identical breeding environment

오한진,김권중,배인규,윤원,이지환,이창희,곽우기,유수동,안지선,양승훈,김곡미,최양일,조진호 충남대학교 농업과학연구소 2019 Korean Journal of Agricultural Science Vol.46 No.2

The purpose of this study was to compare the growth performance, nutrient digestibility, fecal microflora, blood profiles and meat quality of broilers, Korean native chickens and white semi broilers under identical feeding conditions. Sixty 1-d chicks of each type were randomly placed into 12 pens per cage (5 chicks per cage) and fed commercial diets for 28, 49, and 28 days, respectively. The broilers showed a significantly higher (p < 0.05) growth performance from 0 to 4 weeks compared with the other types. Korean native chickens had a significantly higher (p < 0.05) digestibility of dry matter and nitrogen than that of the other species. The blood glucose was significantly higher in the Korean native chickens compared to the other species, and the blood cholesterol was significantly lower. The Lactobacillus content in Korean native chickens was significantly higher (p < 0.05) compared to the other species, and the E. coli content in the broilers was significantly higher (p < 0.05) than in the Korean native chickens and white semi broilers. In terms of meat quality, the breast meat of the broilers had a high water content and pH level. The breast meat of the white semi broilers had a significantly lower (p < 0.05) shear force than that of the other species. In conclusion, there was an interspecific physiological difference due to the age and body weight of the chickens. The broilers had a higher growth performance and meat quality compared to the Korean native chickens and white semi broilers.

Hot-melt extruded copper sulfate affects the growth performance, meat quality, and copper bioavailability of broiler chickens

Kim Min Ju,호세인,Lee Jun Hyung,Kim Kwang Yeoul,Kim Tae Gyun,채병조 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.3

Objective: This study was conducted to evaluate the effects of the supplementation of diets of broiler chickens with hot-melt extruded CuSO4 (HME-Cu) on their growth performance, nutrient digestibility, gut microbiota, small intestinal morphology, meat quality, and copper (Cu) bioavailability. Methods: A total of 225 broilers (Ross 308), one-day old and initial weight 39.14 g, were weighed and distributed between 15 cages (15 birds per cage) in a completely randomized experimental design with 3 treatments (diets) and 5 replicates per treatment. Cages were allotted to three treatments including control (without supplemental Cu), IN-Cu (16 mg/kg of CuSO4), and HME-Cu (16 mg/kg of HME processed CuSO4). Results: The HME-Cu treatment tended to increase the overall body weight gain (p<0.10). The apparent digestibility of Cu was increased by supplementation of HME-Cu at phase 2 (p<0.05). The Escherichia coli count in cecum tended to decrease with the supplementation with Cu (p<0.10). In addition, the HME-Cu treatment had a higher pH of breast meat than the control and IN-Cu treatments (p<0.05). Significant increases in the cooking loss, waterholding capacity, and lightness in the breast were observed in the HME-Cu treatment compared to the control (p<0.05). The Cu content of excreta increased with the Cu supplementation (p<0.05). The concentration of excreta Cu in broilers was decreased in the HMECu compared to the IN-Cu in phase 2 (p<0.05). The Cu concentration in the liver was increased with the HME-Cu supplementation, compared with the control diets (p<0.05). Conclusion: This study showed that HME-Cu supplementation at the requirement level (16 mg/kg diets) in broiler diets did not affect the growth performance and the physiological function of Cu in broilers. However, supplementation of Cu in HME form improved the meat quality and the bioavailability of Cu. Objective: This study was conducted to evaluate the effects of the supplementation of diets of broiler chickens with hot-melt extruded CuSO4 (HME-Cu) on their growth performance, nutrient digestibility, gut microbiota, small intestinal morphology, meat quality, and copper (Cu) bioavailability.Methods: A total of 225 broilers (Ross 308), one-day old and initial weight 39.14 g, were weighed and distributed between 15 cages (15 birds per cage) in a completely randomized experimental design with 3 treatments (diets) and 5 replicates per treatment. Cages were allotted to three treatments including control (without supplemental Cu), IN-Cu (16 mg/kg of CuSO4), and HME-Cu (16 mg/kg of HME processed CuSO4).Results: The HME-Cu treatment tended to increase the overall body weight gain (p<0.10). The apparent digestibility of Cu was increased by supplementation of HME-Cu at phase 2 (p<0.05). The Escherichia coli count in cecum tended to decrease with the supplementation with Cu (p<0.10). In addition, the HME-Cu treatment had a higher pH of breast meat than the control and IN-Cu treatments (p<0.05). Significant increases in the cooking loss, water-holding capacity, and lightness in the breast were observed in the HME-Cu treatment compared to the control (p<0.05). The Cu content of excreta increased with the Cu supplementation (p<0.05). The concentration of excreta Cu in broilers was decreased in the HME-Cu compared to the IN-Cu in phase 2 (p<0.05). The Cu concentration in the liver was increased with the HME-Cu supplementation, compared with the control diets (p<0.05).Conclusion: This study showed that HME-Cu supplementation at the requirement level (16 mg/kg diets) in broiler diets did not affect the growth performance and the physiological function of Cu in broilers. However, supplementation of Cu in HME form improved the meat quality and the bioavailability of Cu.

Effects of onion extracts (Allium cepa) inclusion in diets on growth performance, carcass characteristics, and bone morphometric of broiler chickens

E. Malematja,T. G. Manyelo,J. W. Ng'ambi,M. F. D. Nemauluma,S. D. Kolobe Asian Australasian Association of Animal Productio 2023 Animal Bioscience Vol.36 No.7

Objective: Animal feed companies and researchers are currently embarking on quests for feed additives that could combat the pathogens while promoting growth as well as maintaining quality products. The current study aimed to evaluate the effects of onion extracts on growth performance, carcass quality, and bone morphometrics of broiler chickens. Methods: A total number of 200 one-day-old unsexed Ross 308 broiler chicks were assigned to 5 treatment groups, replicated 4 times. Each replicate (pens) held 10 chickens in a completely randomized design. The experimental diets were then randomly allotted to the pens which act as experimental units. The isoenergetic and isonitrogenous diets were formulated by including onion extracts at 0, 5, 10, 15, or 25 g/kg in a complete broiler diet. Feed intake, and body weight, were recorded then used to calculate feed conversion ratio. At the end of the experiment (42 days), four chickens from each pen were randomly selected for slaughter for carcass, bone morphology and sensory evaluation. Results: Results showed that onion extract supplementation did not affect (p>0.05) growth performances and meat sensory evaluation. However, there was a significantly increased (p<0.05) meat shear force in groups receiving onion extracts dietary treatments. Furthermore, onion extracts improved (p<0.05) bone morphology of broiler chickens in terms of weight, diameter, calcium, and phosphorous contents. Conclusion: In conclusion, onion extracts can be safely included in a commercial broiler diet as a growth promoter without causing adverse effects on growth performance traits and carcass quality in chickens. Onion extract supplementation improved tibia bone growth and strength in broiler chickens.

Effect of Bacillus Subtilis-based Direct-fed Microbials on Immune Status in Broiler Chickens Raised on Fresh or Used Litter

Lee, K.W.,Lillehoj, H.S.,Jang, S.I.,Lee, S.H.,Bautista, D.A.,Siragusa, G.R. Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.11

Type of dietary direct-fed microbials (DFMs) or poultry litter could directly influence the composition of gut microbiota. Gut microbiota plays an important role in shaping the developing immune system and maintaining the homeostasis of the mature immune system in mammal and chickens. The present study was carried out to investigate the interaction among litter, DFMs and immunity in broiler chickens exposed to a field-simulated environment. Immune status of broiler chickens was assessed by serum antibodies against Eimeria spp. and Clostridium spp. and intestinal cytokine mRNA expression. The current experimental design had a $3{\times}2$ factorial arrangement of treatments with three types of litter, i.e., fresh litter or used litter that was obtained from a farm with no disease outbreak (used litter) or a farm with history of a gangrenous dermatitis outbreak (GD litter), and two dietary treatments with or without DFMs. It was found that either DFM addition or type of litter significantly affected anticoccidial antibody levels of broiler chickens at d 42. In general, dietary DFMs increased the anticoccidial antibodies in the fresh-litter raised chickens, but lowered the levels in the GD-litter raised chickens. Serum antibodies against Clostridium perfringens ${\alpha}$-toxin were significantly (p<0.05) higher in chickens raised on GD litter compared with those raised on fresh litter. Cytokine mRNA expression was significantly (p<0.05) altered by either the type of litter or DFMs. Of interest, dietary DFMs lowered interferon-${\gamma}$, interleukin 1beta, and CXCLi2 cytokine mRNA expression in chickens raised on fresh litter but increased them in GD-litter raised chickens. In conclusion, dietary DFMs modulate various immune parameters of broiler chickens, but the DFM-mediated effects were dependent upon the type of litter on which chickens were raised.

유기사료원료로서 소나무껍질 추출물 피타민의 브로일러에 대한 항생제 대체효과

김병완,오진석,한완택,박상오,박병성,Kim, Byong-Wan,Oh, Jin-Seok,Han, Ohan-Taek,Park, Sang-Oh,Park, Byung-Sung 한국유기농업학회 2009 韓國有機農業學會誌 Vol.17 No.1

소나무껍질 추출물, 피타민은 인간의 생체 내 여러 가지 생리활성을 높여주는 항산화성 및 항균성 소재로서 널리 알려져 있다. 본 연구는 브로일러에 대한 유기사료 첨가제로서 소나무 껍질 추출물, 피타민의 첨가효과를 조사하기 위하여 피타민 프리믹스가 첨가된 사료를 부화 후 35일 동안 섭취한 브로일러의 혈중지질, 생산성, 도체특성 및 맹장미생물 변화를 연구하였다. 병아리는 대조구, 항생제 첨가구, 피타민 프리믹스 0.1%, 피타민 프리믹스 0.2% 첨가구로 구분하였다. 브로일러 혈중지질은 피타민 프리믹스 첨가구가 대조구 및 항생제 첨가구에 비해서 유의적으로 낮게 나타났다(p<0.05). 브로일러의 체중은 P 0.1% 첨가구와 항생제 첨가구가 서로 비슷하였으며 P 0.2% 첨가구와 대조구에 비해서 유의적으로 높게 나타났다(p<0.05). 도체중, 도체율, 도체중에 대한 가슴살과 다리살 무게비율은 P 0.1% 첨가구와 항생제 첨가구가 서로 비슷하였으며 대조구에 비해서 유의적으로 높게 나타났다(p<0.05). 복강지방 무게비율은 P 0.1%, P 0.2% 첨가구가 항생제 첨가구 및 대조구에 비해서 유의적으로 낮게 나타났다(p<0.05). 흉선 무게지수는 P 0.1%, P 0.2% 첨가구와 항생제 첨가구가 서로 비슷하였으며 대조구에 비해서 유의적으로 높았다(p<0.05). 장 내 Bifidobacteria는 P 0.1% 첨가구와 항생제 첨가구가 대조구 및 P 0.2% 첨가구에 비해서 유의적으로 높았다(p<0.05). 본 시험에서 나타난 중요한 점은 피타민 5.0%를 함유하는 프리믹스 0.1%를 브로일러 사료에 부화 후 35일 동안 첨가 급여해 줌으로서 항생제 첨가와 동일한 브로일러의 생산성을 유지할 수 있다는 사실이었다. Pitamin is a component of pine bark extract that exhibits antimicrobial activity and a variety of physiological effects. This study was earned out to investigate the effects of dietary pitamin as an organic livestock feed additive in broiler chickens. A 35 day trial was conducted to determine the influence of dietary premix containing 5% pitamin; investigated parameters included blood lipids, growth performance, quality characteristics of carcasses, and changes of caecal microbials in broiler chickens. Chickens were randomly divided into groups that were untreated (control), treated conventionally with antibiotics in the absence of premix, received 0.1 % or 0.2% premix containing 5% pitamin. Plasma lipids were lower in groups fed diets with pitamin premix (p<0.05). The body weight gain from broiler chickens fed with the diet containing 0.1% pitamin premix and antibiotics was similar, and was significantly higher than that of the other groups (p<0.05). The weight of breast muscle and thigh meat of carcasses was similar, and was higher than that of the control group (p<0.05). Abdominal fat and thymus index from chickens receiving either pitamin-supplemented premix was significantly lower and increased, respectively, that of the antibiotic and control groups (both p<0.05). The chickens on the pitamin premix-supplemented diets evidenced significantly higher caecal levels of Bifidobacterium species as compared with the chickens on the control diet (p<0.05). These results suggest that feeding a diet supplemented with a 0.1% premix containing 5.0% pitamin for 35 days maintains the production of broiler chickens at a level comparable to that obtained from the use of antibiotics.

Effects of lycopene on abdominal fat deposition, serum lipids levels and hepatic lipid metabolism-related enzymes in broiler chickens

Wan Xiaoli,Yang Zhengfeng,Ji Haoran,Li Ning,Yang Zhi,Xu Lei,Yang Haiming,Wang Zhiyue 아세아·태평양축산학회 2021 Animal Bioscience Vol.34 No.3

Objective: The present study was conducted to investigate the effects of lycopene on growth performance, abdominal fat deposition, serum lipids levels, activities of hepatic lipid metabolism related enzymes and genes expression in broiler chickens. Methods: A total of 256 healthy one-day-old male Arbor Acres broiler chicks were randomly divided into four groups with eight replicates of eight birds each. Birds were fed basal diet supplemented with 0 (control), 100, 200, and 400 mg/kg lycopene, respectively. Results: Dietary 100 mg/kg lycopene increased the body weight at 21 day of age compared to the control group (p<0.05). Compared to the basal diet, broilers fed diet with 100 mg/kg lycopene had decreased abdominal fat weight, and broilers fed diet with 100 and 200 mg/kg lycopene had decreased abdominal fat percentage (p<0.05). Compared to control, diets with 100, 200, and 400 mg/kg lycopene reduced the levels of total triglyceride and total cholesterol in serum, and diets with 100 and 200 mg/kg lycopene reduced the level of serum low density lipoprotein cholesterol (p<0.05). The activity of fatty acid synthase (FAS) in 400 mg/kg lycopene treated broilers and the activity of acetyl-CoA carboxylase (ACC) in 100, 200, and 400 mg/kg lycopene treated broilers were lower than those fed basal diet (p<0.05). Lycopene increased the mRNA abundance of adenosine monophosphate activated protein kinase α (AMPK-α), whereas decreased the mRNA abundance of sterol regulatory elementbinding protein 1, FAS, and ACC compared to the control group (p<0.05). Conclusion: Dietary lycopene supplementation can alleviate abdominal fat deposition and decrease serum lipids levels, possibly through activating the AMPK signaling pathway, thereby regulating lipid metabolism such as lipogenesis. Therefore, lycopene or lycopenerich plant materials might be added to poultry feed to regulate lipid metabolism. Objective: The present study was conducted to investigate the effects of lycopene on growth performance, abdominal fat deposition, serum lipids levels, activities of hepatic lipid metabolism related enzymes and genes expression in broiler chickens.Methods: A total of 256 healthy one-day-old male Arbor Acres broiler chicks were randomly divided into four groups with eight replicates of eight birds each. Birds were fed basal diet supplemented with 0 (control), 100, 200, and 400 mg/kg lycopene, respectively.Results: Dietary 100 mg/kg lycopene increased the body weight at 21 day of age compared to the control group (p<0.05). Compared to the basal diet, broilers fed diet with 100 mg/kg lycopene had decreased abdominal fat weight, and broilers fed diet with 100 and 200 mg/kg lycopene had decreased abdominal fat percentage (p<0.05). Compared to control, diets with 100, 200, and 400 mg/kg lycopene reduced the levels of total triglyceride and total cholesterol in serum, and diets with 100 and 200 mg/kg lycopene reduced the level of serum low density lipoprotein cholesterol (p<0.05). The activity of fatty acid synthase (FAS) in 400 mg/kg lycopene treated broilers and the activity of acetyl-CoA carboxylase (ACC) in 100, 200, and 400 mg/kg lycopene treated broilers were lower than those fed basal diet (p<0.05). Lycopene increased the mRNA abundance of adenosine monophosphate activated protein kinase α (AMPK-α), whereas decreased the mRNA abundance of sterol regulatory elementbinding protein 1, FAS, and ACC compared to the control group (p<0.05).Conclusion: Dietary lycopene supplementation can alleviate abdominal fat deposition and decrease serum lipids levels, possibly through activating the AMPK signaling pathway, thereby regulating lipid metabolism such as lipogenesis. Therefore, lycopene or lycopenerich plant materials might be added to poultry feed to regulate lipid metabolism.

Effects of intracerebroventricular injection of corticotrophin releasing factor on the gene expression of ghrelin and corticotrophin releasing factor receptors in broiler chickens

Cai, Yuanli,Song, Zhigang Asian Australasian Association of Animal Productio 2022 Animal Bioscience Vol.35 No.12

Objective: This study aimed to investigate the effects of corticotropin-releasing factor (CRF) on the feed intake of broiler chickens and explore its influencing mechanism. Methods: The study included two trials. In trial 1, 32 male broiler chickens (Arbor Acres, Gallus gallus domesticus) were given ventricle buried tubes, and they were allowed to recover for 3 days. At 8:00 AM, intracerebroventricular (ICV) injection with CRF or normal saline was performed in 10-day-old broiler chickens, which were divided into the 5, 10, and 20 ㎍ and control (normal saline) groups according to the dose of CRF injection. In trial 2, chickens were divided into the 10 ㎍ and control group (physiological saline) to repeat trial 1. Results: Results of trial 1 showed that the cumulative amount of feed intake in the 10 or 20 ㎍ groups was considerably lower than that of the control group after ICV injection with CRF. The lowest amount of feed intake was obtained with the addition of 10 ㎍ of CRF. In trial 2, the expression of ghrelin in the hypothalamus injected with 10 ㎍ of CRF increased significantly, but the expression of ghrelin in various sections of the small intestine considerably decreased. The expression of CRF receptor subtypes 1 (CRFR1) in the hypothalamus and some parts of the small intestine remarkably increased, and the expression of CRF receptor subtypes 2 (CRFR2) increased only in the duodenum, whereas the expression of growth hormone secretagogue receptor (GHSR-1α) in the jejunum and ileum increased considerably after ICV injection of 10 ㎍ of CRF. Conclusion: The CRF at 10 ㎍ increased ghrelin expression in the hypothalamus and CRFR1 expression in the small intestine, and this phenomenon was related to the suppressed feed intake of broiler chickens.

Effect of dietary calcium concentrations in phytase-containing diets on growth performance, bone mineralization, litter quality, and footpad dermatitis score in broiler chickens

Kim, Jong Hyuk,Han, Gi Ppeum,Shin, Ji Eun,Kil, Dong Yong Elsevier 2017 Animal feed science and technology Vol.229 No.-

<P><B>Abstract</B></P> <P>This experiment was conducted to investigate the effect of dietary Ca concentrations in phytase-containing diets on growth performance, bone mineralization, litter quality, and footpad dermatitis (FPD) score in broiler chickens. A total of 2100 1-d-old Ross 308 broiler chicks was used and allotted to 1 of 5 dietary treatments with 6 replicates consisting of 70 birds in a completely randomized design. Five commercial-type diets were formulated to contain increasing Ca concentrations of 6.0, 7.0, 8.0, 9.0, or 10.0g/kg. All diets contained 3.5g/kg nonphytate phosphorus and 1000 FTU/kg phytase. Diets were fed to birds for 21 d. At the end of the experiment, birds were sacrificed for tibia sampling and litter samples were collected. The FPD score was measured visually based on a 6-point scale scoring system. Results indicated that increasing Ca concentrations in phytase-containing diets decreased (linear, <I>P<</I> 0.01) body weight gain, feed intake, and feed efficiency of broiler chickens. The concentrations of ash, Ca, and P in the tibia, and tibia breaking strength were not affected by dietary Ca concentrations. Dietary Ca concentrations had no effect on litter quality including pH and moisture and nitrogen contents. A tendency (linear, <I>P</I> =0.10) for increased FPD score was observed as dietary Ca concentrations were increased. In conclusion, increasing Ca concentrations from 6.0 to 10.0g/kg in phytase-containing diets have negative effects on growth performance of broiler chickens during 21 d posthatch, possibly due to decreased FI and subsequent phytase intake. Increasing Ca concentrations in phytase-containing diets have little impact on litter quality but tend to increase FPD incidence in broiler chickens.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The effect of dietary calcium concentrations was determined with broiler chickens. </LI> <LI> Decreasing calcium concentrations in diets improved broiler performance. </LI> <LI> Decreasing calcium concentrations in diets reduced footpad dermatitis score. </LI> </UL> </P>