One alpha-hydroxycholecalciferol improves growth performance, tibia quality, and meat color of broilers fed calcium- and phosphorus-deficient diets.
Abstract: An experiment was conducted to evaluate the effects of one alpha-hydroxycholecalciferol (1[alpha]-OH [D.sub.3]) on growth performance, tibia quality, and skin and meat color in broilers fed calcium (Ca)- and phosphorus (P)-deficient corn-soybean meal diets. A total of 288 male Ross broilers, at 21 days of age, were randomly assigned to three treatments with eight cages per treatment. Three levels of 1[alpha]-OH [D.sub.3] (0, 5, and 10 [micro]g/kg) were added to a basal diet (0.50% Ca, 0.13% non-phytate phosphorus (NPP), and 0.35% total phosphorus (tP)) without vitamin [D.sub.3]. As a result of this study, the addition of 1[alpha]-OH [D.sub.3] increased body weight gain (p<0.001), feed intake (p = 0.007), feed efficiency (p<0.001), tibia weight (p = 0.002), length (p<0.001), breaking-strength (p = 0.012), ash (p<0.001), Ca (p<0.001), and P content (p = 0.004). Dietary 1[alpha]-OH [D.sub.3] enhanced breast meat yellowness (p = 0.015) and the length and weight of the small intestine of the broilers. Moreover, 1 [alpha]-OH [D.sub.3] decreased serum Ca concentration (p = 0.074) and breast meat redness (p = 0.010). These results indicate that the 1 [alpha]-OH [D.sub.3] improves growth, tibia quality, and meat color in broilers fed Ca- and P-deficient cornsoybean meal diets. (Key Words : One Alpha-hydroxycholecalciferol, Growth Performance, Tibia Quality, Meat Color, Broiler)
Article Type: Report
Subject: Broilers (Poultry) (Food and nutrition)
Meat (Quality)
Meat (Research)
Authors: Han, J.C.
Wang, Y.L.
Qu, H.X.
Liang, F.
Zhang, J.L.
Shi, C.X.
Zhang, X.L.
Li, L.
Xie, Q.
Wang, C.L.
Yan, Y.Y.
Dong, X.S.
Cheng, Y.H.
Pub Date: 02/01/2012
Publication: Name: Asian - Australasian Journal of Animal Sciences Publisher: Asian - Australasian Association of Animal Production Societies Audience: Academic Format: Magazine/Journal Subject: Agricultural industry; Biological sciences Copyright: COPYRIGHT 2012 Asian - Australasian Association of Animal Production Societies ISSN: 1011-2367
Issue: Date: Feb, 2012 Source Volume: 25 Source Issue: 2
Topic: Event Code: 310 Science & research
Product: Product Code: 0251000 Chickens, Broilers; 2048001 Feed Supplements & Concentrates NAICS Code: 11232 Broilers and Other Meat Type Chicken Production; 311119 Other Animal Food Manufacturing SIC Code: 2015 Poultry slaughtering and processing; 2048 Prepared feeds, not elsewhere classified
Geographic: Geographic Scope: China Geographic Code: 9CHIN China
Accession Number: 276186781
Full Text: INTRODUCTION

As an analog of cholecalciferol (vitamin [D.sub.3]), the one alpha-hydroxycholecalciferol (1[alpha]-OH [D.sub.3]) is slightly lower in efficacy than 1,25-dihydroxycholecalciferol (1,25-[(OH).sub.2] [D.sub.3]) in broilers (Edwards, 2002). Biehl and Baker (1997b) and Snow et al. (2004) reported that 1[alpha]-OH [D.sub.3] improves growth performance, tibia quality, and phosphorus (P) utilization in broilers. However, most studies focus only on starter broilers, and to date, limited information is available on growing-finishing phase birds.

Previous studies on 1 [alpha]-OH [D.sub.3] have been based on adequate dietary vitamin [D.sub.3] (Biehl and Baker, 1997a, 1997b; Snow et al., 2004; Driver et al., 2005). Edwards (2002) found that an interaction between vitamin [D.sub.3] and 1,25-(OH)2 [D.sub.3] exists in tibia ash. To avoid possible interactions between vitamin [D.sub.3] and 1 [alpha]-OH [D.sub.3], we investigate the effect of 1 [alpha]-OH [D.sub.3] in a basal diet without vitamin [D.sub.3]. Our unpublished data showed that 1 [alpha]-OH [D.sub.3] efficacy responds negatively to increasing dietary calcium (Ca) levels, and 1 [alpha]-OH [D.sub.3] yields the highest activities at low concentrations of dietary Ca (Han et al., 2012). Therefore, in the present experiment, a low-Ca diet was designed.

Broiler skin and meat color is important sensory characteristics by which consumers judge meat quality (Petracci and Fletcher, 2002). In our published work, Han et al. (2009) found that 1 [alpha]-OH [D.sub.3] enhances the lightness and yellowness of breast and thigh meat of 1- to 21-d-old broilers. Previous studies on swine showed that the lightness of pork decreases and the redness increases or is not affected, by the addition of vitamin [D.sub.3] (Wiegand et al., 2002; Wilborn et al., 2004). However, the effects of 1a-OH [D.sub.3] on skin color in broilers have not been examined. Petracci and Fletcher (2002) reported that broiler skin and meat color dramatically changes during the first 6 h postmortem. Thus, broiler skin and meat color were determined immediately after the broilers were slaughtered.

The effect of 1[alpha]-OH [D.sub.3] on weight and length of small intestine remains unclear. Therefore, the objective of the current experiment is to evaluate the effects of 1[alpha]-OH [D.sub.3] on growth performance, tibia quality, skin and meat color, as well as small intestine parameters in broilers fed Ca- and P-deficient diets.

MATERIALS AND METHODS

Birds, diets, and management

All procedures in the present experiment were approved by the Animal Care Committee of Shangqiu Normal University.

On the day of hatch, 288 male Ross broiler chicks were randomly and equally assigned to 24 cages (70x70x30 cm), with 12 chicks per cage. All chicks were fed a starter mash feed (apparent metabolizable energy (AME), 2,940 kcal/kg; crude protein (CP), 20%; Ca, 1%; total phosphorus (tP), 0.68%; non-phytate phosphorus (NPP), 0.45%) until they were three weeks old. On d 21, the broilers were individually weighed, transferred to growing-finishing cages (200x50x35 cm), and then assigned to one of the three dietary treatments with eight replicates per treatment. Three levels of 1[alpha]-OH [D.sub.3] (0, 5, and 10 ^g/kg) were added to a basal diet (0.50% Ca, 0.13% NPP, 0.35% tP) without vitamin [D.sub.3] (Table 1). The crystalline 1[alpha]-OH [D.sub.3], supplied by Taizhou Healtech Chemical Co., Ltd. (Taizhou, China), was dissolved in ethanol, and then brought to a final concentration of 10 mg/L of 1[alpha]-OH [D.sub.3] in a solution of 5% ethanol and 95% propylene glycol (Biehl and Baker, 1997b).

The birds were given access to mash feed and water ad libitum during the 21-d experiment, with an 18-h lighting schedule.

Collection and analysis of samples

To collect blood and tibias, two chicks were randomly selected from each replicate and weighed (Edwards, 2002). Blood samples (5 ml) were collected into 5-ml anticoagulated syringes (Shanghai K&G International Co. Ltd., Shanghai, China) through the wing vein, and then centrifuged for 10 min at 3,000 g at 20[degrees]C. The birds were sacrificed by exsanguination. Serum Ca and inorganic phosphate (Pi) were determined with a Shimadzu CL-8000 Analyzer (Shimadzu Corp., Kyoto, Japan) following the manufacturer's instructions.

The left and right tibias of the individual birds were excised. According to the method by Hall et al. (2003), the left tibias were boiled for 5 min to loosen the muscle tissues. The meat, connective tissue, and the fibula bone were then removed completely using scissors and forceps. After the tibias were cleaned, they were put into a container with ethanol for 48 h (removing water and polar lipids). The bones were further extracted in anhydrous ether for 24 h (removing non-polar lipids). The tibias were dried at 105[degrees]C for 24 h, and then weighed. The tibia diameter was determined at the medial point, and the tibia ash content was determined by ashing the bone in a muffle furnace for 18 h at 600[degrees]C (Han et al., 2009). Skin color values of lightness ([L.sup.*]), redness ([a.sup.*]), and yellowness ([b.sup.*]) were determined on the area between the pectoral and sternal feather tracts and the meat colors measured on the raw muscles (Petracci and Fletcher, 2002). Color values of skin and meat were measured by a Chroma Meter WSC-S (Shanghai Precision and Scientific Instrument Co., Ltd., Shanghai, China).

The right tibia was used to analyze the breaking-strength. Tibia breaking-strength was determined using an all-digital electronic universal testing machine (Shenzhen Hengen Instrument Co. Ltd., Shenzhen, China). The tibias were cradled on two support points 4 cm apart. By using a 50-kg load cell and a crosshead speed of 10 mm/min, force was applied to the midpoint of the same facial of each tibia (Jendral et al., 2008).

The whole small intestine was isolated immediately from the gastrointestinal tract and cut into 3 pieces: duodenum, jejunum, and ileum. The weight and length of the three intestinal pieces were measured (Wang and Peng, 2008).

Statistical analysis

The replicate means served as the experimental unit for statistical analysis. All data were analyzed using the ANOVA procedure of SAS software (SAS Institute, 2001) as factorial experiments, with all statements of significance p<0.05 unless indicated otherwise.

RESULTS AND DISCUSSION

Growth performance and tibia quality

The diet consisting of 0.50% Ca and 0.13% NPP resulted in severe deficiencies of Ca and P in the broilers. The body weight gain (BWG) in birds fed basal diets was only 467 g (Table 2). The addition of 5 and 10 ^g/kg of 1[alpha]-OH [D.sub.3] corrected the Ca and P deficiency and increased the BWG to 745 and 949 g, respectively. Dietary 1[alpha]-OH [D.sub.3] also improved feed intake (FI, p = 0.007), feed efficiency (FE, p<0.001), tibia weight (p = 0.002), length (p<0.001), breaking-strength (p = 0.012), ash (p<0.001), Ca (p< 0.001), and P content (p = 0.004). However, 1[alpha]-OH [D.sub.3] did not significantly increase serum Pi (p = 0.261) or decreased the serum Ca concentration (p = 0.074).

Research has shown that sodium-dependent phosphate absorption by intestinal brush-border membrane vesicles (BBMV) decreases with age in rats; NaPi-IIb gene expression also decreases proportionally with age (Xu et al., 2002). The compound 1[alpha]-OH [D.sub.3] is metabolized to 1,25-(OH)2 [D.sub.3] in the intestines of chicks (Edelstein et al., 1978). Dietary 1,25-(OH)2 [D.sub.3] increases phosphate absorption in suckling and adult rats and enhances NaPi-IIb mRNA abundance in suckling rats (Xu et al., 2002). However, 1,25-(OH)2 [D.sub.3] has no effect on NaPi-IIb mRNA in adults (Xu et al., 2002). These results indicate that the efficacy of vitamin D analogue on P metabolism is influenced by animal age.

Previous studies on 1[alpha]-OH [D.sub.3] have been based on starter broilers, in which 1[alpha]-OH [D.sub.3] improves growth performance, tibia ash, and P retention (Biehl and Baker, 1997b; Edwards, 2002). In the present study, the addition of 1[alpha]-OH [D.sub.3] increased BWG, FI, and FE in Ca- and P-deficient diets of 21- to 42-d-old broilers, which agreed with the results of 1- to 21-d-old broilers reported by Snow et al. (2004). Tibia quality was also enhanced by the addition of 1[alpha]-OH [D.sub.3]. The tibia weight and breaking-strength improvement by 1[alpha]-OH [D.sub.3] came from the increase in tibia Ca and P. Dietary 1[alpha]-OH [D.sub.3] decreased serum Ca concentration (p = 0.074), which agreed with the previous research on starters by Edwards (2002) and Han et al. (2009). The addition of 1[alpha]-OH [D.sub.3] showed a trend of increasing serum Pi concentration, but the difference was not significant.

Skin and meat color

The addition of 1 [alpha]-OH [D.sub.3] did not influence the skin color of 21- to 42-d-old broilers (Table 3), but increased breast meat yellowness (b value, p = 0.015) and decreased its redness (a value, p = 0.010). The thigh meat redness in 10 Mg/kg of the 1 [alpha]-OH [D.sub.3] group was lower than that of the 5 Mg/kg of 1[alpha]-OH [D.sub.3] group (p = 0.027).

Previous studies have shown that vitamin [D.sub.3] improves the lightness and redness of pork (Wiegand et al., 2002; Wilborn et al., 2004), while 1 [alpha]-OH [D.sub.3] increases the lightness and yellowness of the breast and thigh meat of starter broilers (Han et al., 2009). In the current study, 1 [alpha]-OH [D.sub.3] enhanced breast meat yellowness and decreased its redness. Meat color is affected by pH and myoglobin. The pH value of breast meat or thigh meat is related positively to redness, but negatively to lightness and yellowness (Allen et al., 1998; Fletcher, 1999; Fletcher et al., 2000; Qiao et al., 2002). A low pH reduces the importance of myoglobin in selectively absorbing green light, resulting in meat that appears less red and more yellow (Castellini et al., 2002).

Small intestine features

The addition of 1 [alpha]-OH [D.sub.3] increased the length (p = 0.027, p = 0.010, p = 0.009, p = 0.001) and weight (p< 0.001, p<0.001, p<0.001, p<0.001) of the duodenum, jejunum, ileum, and the whole small intestine, respectively. Fassbinder-Orth and Karasov (2006) have found that feed restriction don't significantly influence the small intestine weight in the Leghorn cockerel chicks. Thus, the small intestine weight and length in boilers fed basal diets were lower significantly than those of birds fed diets with 1 [alpha]-OH [D.sub.3], which had nothing to do with feed intake in our experiment. Previous research has shown that the addition of vitamin [D.SUB.2] or [D.sub.3] results in longer and thinner villi and higher duodenal mucosa weights in rats (Urban and Schedl, 1969; Sampson and Krawitt, 1976). Peebles et al. (2011) reported that percentage of duodenum weight in birds fed 1.5% poultry fat with phytase and 25-OH [D.sub.3] was greater than that of birds fed 0.75% poultry fat. In the present study, 1 [alpha]-OH [D.sub.3] increased the small intestine weight and length of broilers fed with Ca- and P-deficient diets. These data suggest that vitamin [D.sub.3] and its metabolites can stimulate intestine development.

In conclusion, by increasing feed intake, improving feed efficiency, stimulating small intestine development, and facilitating Ca and P retention in bones, 1 [alpha]-OH [D.sub.3] improves growth, tibia quality, and meat color.

10.5713/ajas.2011.11320

ACKNOWLEDGEMENTS

This work was supported by the National Natural Science Foundation of China (No. 31101732), the Henan Province Programs for Science and Technology Development (No. 102102110173), the Natural Science Foundation of Henan Province (No. 2011B230011), and the Youth Foundation of Shangqiu Normal University (No.

2009QN11).

Received September 7, 2011; Accepted November 2, 2011

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* Corresponding Author : Y. H. Cheng. College of Bioresources, Department of Animal Science, I-Lan University, I-Lan, Taiwan, 26047, ROC. Tel: +886-39317712, Fax: +886-39359005, E-mail: yhcheng@niu.edu.tw

J. C. Han, Y. L. Wang, H. X. Qu, F. Liang, J. L. Zhang, C. X. Shi, X. L. Zhang, L. Li, Q. Xie, C. L. Wang, Y. Y. Yan, X. S. Dong (1) and Y. H. Cheng *

College of Life Science, Shangqiu Normal University, Shangqiu, Henan, 476000, China

(1) Taizhou Healtech Chemical Co., Ltd., Taizhou, Zhejiang, 318000, China.
Table 1. Ingredients and nutrient composition of the basal diet

Ingredient (%)                   Basal diet

Corn                                68.74
Soybean meal                        26.46
Soybean oil                          0.60
Swine lard                           0.39
Corn gluten meal                     1.80
Limestone                            1.14
L-lysine-HCl                         0.18
DL-methionine                        0.06
Trace mineral premix (1)             0.10
Vitamin premix (2)                   0.03
Choline chloride                     0.20
Sodium chloride                      0.30
Nutrient composition
  Metabolizable energy (MJ/kg)      12.51
  Calculated CP (%)                 18.50
  Analyzed CP (%)                   18.90
  Calculated Ca (%)                  0.50
  Analyzed Ca (%)                    0.67
  Calculated total P (%)             0.35
  Analyzed total P (%)               0.42
  Calculated non-phytate P (%)       0.13

(1) The trace mineral premix provided (per kg of diet): iron,
100 mg; zinc, 100 mg; copper, 8 mg; manganese, 120 mg;
iodine, 0.7 mg; and selenium, 0.3 mg.

(2) The vitamin premix provided (per kg of diet): vitamin A,
8,000 IU; vitamin E, 20 IU; menadione, 0.5 mg; thiamine,
2.0 mg; riboflavin, 8.0 mg; niacin, 35 mg; pyridoxine,
3.5 mg; vitamin B12, 0.01 mg; pantothenic acid, 10.0 mg;
folic acid, 0.55 mg; and biotin, 0.18 mg.

Table 2. Effect of 1[alpha]-OH [D.sub.3] on growth performance,
serum minerals, and tibia qualities of 21- to 42-d-old broilers (1)

Item (2)           1[alpha]-OH [D.sub.3] ([micro]g/kg)

                       0          5                 10
Growth
  BWG (g)            467 (c)     745 (b)       949 (a)
  FI (g)           1,590 (b)   1,818 (ab)    2,092 (a)
  FE (BWG/FI)       0.29 (b)    0.41 (a)      0.45 (a)
Serum
  Ca (mg/100 ml)   11.59 (a)   10.32 (ab)     8.87 (b)
  Pi (mg/100 ml)    2.24        2.58          2.98
Tibia
  Weight (g)        2.66 (b)    2.93 (b)      3.45 (a)
  Length (cm)       6.52 (c)    7.24 (b)      7.78 (a)
  Width (cm)        0.74        0.68          0.74
  Breaking-        79.87 (b)   71.10 (b)    107.40 (a)
  strength (N)
  Ash (%)          32.61 (b)   37.74 (a)     38.93 (a)
  Ca (%)           12.12 (b)   14.10 (a)     14.49 (a)
  P (%)             5.53 (b)    6.49 (a)      6.77 (a)

Item (2)           SEM (3)   p value

Growth
  BWG (g)            46      <0.001
  FI (g)             70       0.007
  FE (BWG/FI)       0.02     <0.001
Serum
  Ca (mg/100 ml)    0.49      0.074
  Pi (mg/100 ml)    0.17      0.261
Tibia
  Weight (g)        0.10      0.002
  Length (cm)       0.12     <0.001
  Width (cm)        0.02      0.210
  Breaking-         5.49      0.012
  strength (N)
  Ash (%)           0.74     <0.001
  Ca (%)            0.27     <0.001
  P (%)             0.17      0.004

(1) Data are means of 8 replicate cages consisting of 12 birds per
replicate cage.

(2) BWG = Body weight gain, FI = Feed intake, FE = Feed efficiency,
Ca = Calcium, Pi = Inorganic phosphate, P = Phosphorus.

(3) SEM = Pooled standard error of the mean.

Table 3. Effect of 1[alpha]-OH [D.sub.3] on skin, breast meat, and
thigh meat color of 21- to 42-d-old broilers (1)

Item                   1[alpha]-OH [D.sub.3]             SEM      p
                           ([micro]g/kg)                 (2)    value

                      0            5           10

Skin
  Lightness (L*)    55.45        55.45       55.36       0.55   0.997
  Redness (a*)      10.65         9.47        9.21       0.43   0.369
  Yellowness (b*)   23.11        21.56       21.32       0.60   0.437
Breast meat
  Lightness (L*)    47.34        47.30       47.75       0.46   0.914
  Redness (a*)      10.65 (a)    10.74 (a)    8.59 (b)   0.35   0.010
  Yellowness (b*)   18.74 (b)    19.73 (b)   21.62 (a)   0.43   0.015
Thigh meat
  Lightness (L*)    47.81        47.38       49.51       0.61   0.336
  Redness (a*)      10.30 (ab)   11.52 (a)    8.69 (b)   0.45   0.027
  Yellowness (b*)   10.37        12.39       11.57       0.60   0.401

(1) Data are means of 8 replicates consisting of 2 birds per
replicate.

(2) SEM = Pooled standard error of the mean.

Table 4. Effect of 1 [alpha]-OH [D.sub.3] on small intestine length and
weight of 21- to 42-d-old broilers (1)

Item               1[alpha]-OH [D.sub.3] ([micro]g/kg)    SEM (2)

                     0            5             10
Duodenum
 Length (cm)       27.56 (b)    30.78 (a)     30.69 (a)    0.58
 Weight (g)         8.25 (b)    11.36 (a)     12.55 (a)    0.54
Jejunum
 Length (cm)       47.30 (b)    54.93 (ab)    59.84 (a)    1.85
 Weight (g)        11.91 (c)    16.16 (b)     21.96 (a)    1.09
Ileum
 Length (cm)       45.04 (b)    53.50 (ab)    60.74 (a)    2.21
 Weight (g)         8.45 (b)    16.01 (a)     18.91 (a)    1.11
Small intestine
 Length (cm)      119.90 (b)   139.21 (a)    151.27 (a)    3.95
 Weight (g)        28.61 (c)    43.53 (b)     53.42 (a)    2.41

Item               p value

Duodenum
 Length (cm)        0.027
 Weight (g)       < 0.001
Jejunum
 Length (cm)        0.010
 Weight (g)       < 0.001
Ileum
 Length (cm)        0.009
 Weight (g)       < 0.001
Small intestine
 Length (cm)        0.001
 Weight (g)       < 0.001

(1) Data are means of 8 replicates consisting of 2 birds per replicate.

(2) SEM = Pooled standard error of the mean.
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