Animal (2011), 5:10, pp 1506–1514 & The Consortium 2011 animal doi:10.1017/S1751731111000589

Estimating the requirement of dietary crude protein for growing blue-breasted ( chinensis)

- H. W. Wei1, T. L. Hsieh1, S. K. Chang2, W. Z. Chiu1, Y. C. Huang1 and M. F. Lin1

1Department of Animal Science and Technology, National Taiwan University, No. 50, Lane 155, Section 3 Keelung Road, Taipei 106, Taiwan; 2School of Veterinary Medicine, National Taiwan University, No. 1, Sector 4 Roosevelt Road, Taipei 106, Taiwan

(Received 11 August 2010; Accepted 15 March 2011; First published online 26 April 2011)

Two experiments were conducted to investigate the requirement for dietary crude protein (CP) in growing blue-breasted quail (BBQ). In Experiment 1, 300 1-day-old were randomly assigned to 10 groups according to a 2 3 5 factorial arrangement of treatments with two metabolisable energy (ME) levels (12.13 and 13.39 MJ/kg) and five CP concentrations (160, 190, 220, 250 and 280 g/kg) for 8 weeks. In Experiment 2, 300 1-day-old quails were subjected to a different factorial arrangement of treatments with two ME levels (11.51 and 12.13 MJ/kg) and five CP concentrations (210, 220, 230, 240 and 250 g/kg) for 28 days. Experiment 1 revealed that an interaction existed in weight gain between ME and CP levels in weeks 1 to 4. In both ME groups, quails receiving CP of 160 g/kg showed the least weight gains (P , 0.05). No differences (P . 0.05) existed in weight gain between the ME groups in which quails ingested CP of 250 and 280 g/kg, whereas quails consuming CP of 220 g/kg with an ME of 13.39 MJ/kg had smaller weight gain than did those ingesting higher CP concentrations (P , 0.05). Of main effects for weeks 1–4, quails treated with an ME of 12.13 MJ/kg consumed more feed than did those receiving another ME level, whereas quails in both ME treatments showed similar feed efficiencies. For weeks 5 to 8, no difference (P . 0.05) in weight gain, feed intake and feed efficiency was seen regardless of ME levels, and no interaction existed between ME and CP levels. In Experiment 2, the best weight gain and feed efficiency were achieved when the dietary CP concentration was more than 210 g/kg, and quails treated with 11.51 MJ/kg showed better weight gain and feed efficiency (P , 0.05) than did those that received 12.13 MJ/kg. Furthermore, the weight gains and protein intakes on the basis of per MJ from the two experiments were pooled together to estimate the protein intake necessary for the best growth performance by two mathematic models; they were then converted to dietary CP concentrations of 204 (minimum) and 233 g/kg (maximum) when ME was 11.51 MJ/kg. In conclusion, BBQ will achieve good growth performance with dietary CP of more than 204 g/kg on the basis of an ME of 11.51 MJ/kg in weeks 1 to 4.

Keywords: blue-breasted quail, crude protein, metabolisable energy, requirement

Implications Introduction This study aimed to establish the dietary crude protein The blue-breasted quail (BBQ) is the smallest quail in the requirement for growing blue-breasted quail (BBQ). The BBQ is family ; it is kept mainly for egg production the smallest quail and is considered a good laboratory model and is considered to be a good laboratory model for avian for avian research because of its hardiness, small size, short research (Tsudzuki, 1994) because of its hardiness, small generation interval and excellent reproductive performance. body size, short generation interval, excellent reproductive There are, however, little data on its nutrient requirements. performance and easily distinguishable gender after 4 weeks Literature indicates BBQ are fed turkey starter, lettuce leaves, of age. Recent BBQ experiments have focused on hormones finch seed, tubeworms and/or larvae. If the BBQ is to become a (Andersson et al., 2004; Lo˜ hmus and Sundstrom, 2004; useful small animal model, similar to the mice, it is necessary to Lo˜ hmus et al., 2006), embryonic development (Ono et al., establish its nutrient requirements. 2005), disease (Morita et al., 1999) and flight dynamics (Askew et al., 2001; Askew and Marsh, 2001 and 2002). There are, however, little data on its nutrient requirements. - E-mail: mfl[email protected] If the BBQ is to become a useful small animal model for

1506 Protein requirement of growing blue-breasted quail

Table 1 Ingredient composition and calculated analysis of diets (g/kg as fed; Experiment 1)

ME (MJ/kg) 12.13 13.39

CP (g/kg) 160 190 220 250 280 160 190 220 250 280

Ingredient (g/kg) Maize (8% CP) 659 665 623.2 478.6 385.3 700 728.3 681.6 419.5 311 Casein (92% CP) 25.5 84.8 57 – – 21 77.6 50 – – Soyabean meal (44% CP) – – 109.9 391.4 479.6 – – 140.9 402.7 493.8 Fish meal (72% CP) 50 50 50 50 50 50 50 50 50 50 Soyabean oil 23.7 10.8 4.4 30.9 45.3 44.9 23.9 24.7 87.3 107 Salt 3 3 3 3 3 3 3 3 3 3

Vitamin- and trace mineral-- premix 5 5 5 5 5 5 5 5 5 5 CaHPO4 19.1 19.1 17.7 14.2 13.4 18.9 18.8 16.9 14.3 13.5 CaCO3 17.5 17.4 14.5 14.5 14.3 17.6 17.6 17.7 14.4 14.2 Sand (SiO2) 144.7 124.4 70.8 8.6 1.7 86.3 54.1 – – – Choline chloride (50%) 2 2 2 2 2 2 2 2 2 2 DL-Methionine 4.7 2.7 2.4 1.2 0.4 4.7 2.8 2 1.3 0.5 L-Isoleucine 5 2 1.6 – – 5.1 2.2 1 – – L-Lysine 8.2 2.5 1.9 – – 8.5 3 1.1 – – L-Threonine 5.7 3.2 3 0.6 – 5.8 3.3 2.2 0.5 – L-Phenylalanine 8.3 1.9 1.1 – – 8.5 2.2 – – – L-Arginine 8.4 5.8 3.2 – – 8.4 5.8 1.9 – – L-Tryptophan 1.1 0.4 – – – 1.1 0.4 – – – L-Valine 3.3 – – – – 3.4 – – – – L-Leucine 5.3 – – – – 5.3 – – – – L-Histidine 0.5 – – – – 0.5 – – – – L-Glutamic acid – – 29.3 – – – – – – – Total 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 Analysis (g/kg) Dry matter 897.2 895.4 884.9 870.5 876.5 895.3 886.3 875.9 880.1 893.4 CP 153.2 190.0 236.6 263.0 294.8 173.6 192.5 228.8 265.2 293.8 Calculated value (g/kg) Lysine 13.0 13.0 13.0 14.5 16.6 13.0 13.0 13.0 14.7 16.8 Methionine1cysteine 9.4 9.4 9.4 9.4 9.4 9.4 9.4 9.4 9.4 9.4 Threonine 10.2 10.2 10.2 10.2 10.9 10.2 10.2 10.2 10.2 10.9 Tryptophan 2.2 2.2 2.3 3.6 4.2 2.2 2.2 2.6 3.7 4.3 ME 5 metabolisable energy. - Vitamins per kilogram of diet: retinyl acetate, 4500 IU; cholecalciferol, 1000 ICU; DL-a-tocopheryl acetate, 30 IU; Vitamin K3, 2 mg; Vitamin B1, 3.36 mg; Vitamin B2,

6 mg; Vitamin B , 4.86 mg; Ca-pantothenate, 54.59 mg; folic acid, 2.04 mg; biotin, 0.3 mg; niacin, 50 mg and Vitamin B , 0.01 mg. - 6 12 - Mineral supplement per kilogram of diet: Cu (CuSO4 5H2O, 25.45% Cu), 5.55 mg; Fe (FeSO4 7H2O, 20.09% Fe), 133.34 mg; Mn (MnSO4 H2O, 32.49% Mn), 67.32 mg; Zn (ZnSO4 7H2O, 22.74% Zn), 55.03 mg and Se (NaSeO3 5H2O, 30.03% Se) 0.15 mg. research, as is the mouse, it is necessary to establish its nutrient different colours and numbers for identification, and weighing requirements for the preparation of practical or synthetic feed. 3.80 6 0.40 g, were raised in 30 individual cages (48 3 33 cm2) As protein is a major nutrient for growth and maintenance holding10birdseach,accordingtoa23 5 factorial arrange- (Pond et al., 2005), establishing its requirement should be ment of treatments with 2 ME levels (12.13 and 13.39 MJ/kg) the first priority. The aim of this research was to estimate the and 5 CP concentrations (160, 190, 220, 250 and 280 g/kg). As requirement of dietary crude protein (CP) for growing BBQ. it is very difficult to distinguish the genders of newly hatched As the dietary metabolisable energy (ME) concentration quails, the 1-day-old quails were assigned to each pen at ran- affects protein utilisation, the possibility of an effect of ME dom. After 4 weeks of age, the genders of the quail were concentration on CP requirements was also investigated. recognised by their appearance. Data from 132 females and 134 males were analysed. These numbers exclude that died during the experiment, most of whom were in the lower Material and methods CP treatments. The temperature in each brooder was main- Experiment 1 tained at 40 6 18C for the first 2 weeks (Bernstein, 1971), and A total of 300 1-day-old quails from a flock reared at National was subsequently decreased by 28Cevery2daysto308C. Water Taiwan University, hatched by electrically heated incubators, and feed (Table 1) were supplied ad libitum for 8 weeks. In the wearing leg rings made by small-size plastic cable ties with absence of previous data, the concentrations of individual

1507 Wei, Hsieh, Chang, Chiu, Huang and Lin

Table 2 Ingredient composition and calculated analysis of diets (g/kg as fed; Experiment 2)

ME (MJ/kg) 11.51 12.13

CP (g/kg) 210 220 230 240 250 210 220 230 240 250

Ingredient (g/kg) Maize (8% CP) 574 562.4 549.2 502.7 450.6 625.5 598.5 582.4 560.8 528.6 Casein (92% CP) 60 55 50 45 35 54 50 45 40 35 Soyabean meal (44% CP) 138.1 182.8 209 267.1 322 142.7 190.2 229.3 266.6 307 Fish meal (72% CP) 50 50 50 50 50 50 50 50 50 50 Soyabean oil 9.4 6.2 4.2 13.8 25.2 8.8 11 10 11.1 15.9 Salt 3 3 3 3 3 3 3 3 3 3

Vitamin- and trace mineral-- premix 5 5 5 5 5 5 5 5 5 5 CaHPO4 8.7 8.1 7.7 7.1 6.5 8.4 7.8 7.3 6.9 6.4 CaCO3 13.7 13.7 13.7 13.7 13.6 13.8 13.8 13.8 13.8 13.8 Sand (SiO2) 126.1 105.6 91.5 87.5 84.6 78 64.8 49.4 37.8 30.9 Choline chloride (50%) 2 2 2 2 2 2 2 2 2 2 DL-Methionine 2.1 1.8 1.6 1.2 1.1 2.1 1.7 1.4 1.2 1 L-Isoleucine 0.8 0.2 – – – 0.9 0.2 – – – L-Lysine 0.6 – – – – 0.8 – – – – L-Threonine 2.1 1.6 1.4 0.8 0.4 2.2 1.6 1.2 0.8 0.4 L-Arginine 2.1 0.6 – – – 1.9 0.4 – – – L-Glutamic acid 2.3 2 11.7 1.1 1 0.9 – 0.2 1 1 Total 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 Analysis (g/kg) Dry matter 886.6 873.1 886.2 883.2 884.7 885.1 884.6 882.8 883.6 884.8 CP 203.4 220.0 228.1 237.1 253.1 200.7 210.1 233.1 246.2 251.8 Calculated value (g/kg) Lysine 13 13.3 13.6 14.7 21.3 13 13.3 13.9 14.4 15.1 Methionine1cysteine 9.4 9.4 9.4 9.4 9.4 9.4 9.4 9.4 9.4 9.4 Threonine 10.2 10.2 10.2 10.2 10.2 10.2 10.2 10.2 10.2 10.2 Tryptophan 2.5 2.8 3.2 3.3 3.5 2.5 2.8 3.0 3.2 3.4

ME 5 metabolisable energy.

-, -Identical- to those in Experiment 1. essential amino acids, vitamins and minerals in the diets were lasted only 28 days. The factorial arrangement of the diets set to satisfy or exceed the requirements of broilers, Japanese included 2 ME levels (11.51 and 12.13 MJ/kg) and 5 CP quails and Bobwhite quails recommended by the National concentrations (210, 220, 230, 240 and 250 g/kg; Table 2). Research Council (NRC) in 1994. Feed intake per cage and Data from 146 females and 149 males were analysed and individual BWs were recorded every 7 days. When a dead these numbers exclude animals that died during the experi- was observed, its BW was recorded. Feed consumption was ment. The weekly individual BWs and feed intake per cage attributed to remaining in that cage if the dead bird had were measured over the entire experimental period. lost weight, that is, the bird was supposed to lose its appetite before it died. Provided that the BW of the dead was heavier Analyses than its preceding record, its feed intake from last time until the The moisture and nitrogen concentrations of the diets were day it died was calculated by its weight gain and the average measured by oven-drying and by the Kjeldahl method, feed efficiency of other cages in the same treatment. This according to the Association of Official Analytical Chemists datum was subtracted from the total feed consumption of that (2000, Methods 953.07 and 984.13). The measured CP cage. The average weight gain per feed intake of that cage was contents of the diets were used for CP intake calculation and calculated by the feed intake corrected and the weight gain of requirement estimation. the remaining quails. The previous BW records of the dead were not included in statistical analysis. As the average cage BW and Statistical analysis intake values were utilised to estimate feed efficiency, the First, data were statistically analysed according to the 2 replicates were three for each ME–CP combination treatment. (ME) 3 5 (CP) factorial arrangements of treatments using the SAS GLM procedure (2002); differences among groups Experiment 2 were determined by utilising Tukey’s honestly significant The number of quails and their management in Experiment 2 difference test after ANOVA. A level of P , 0.05 was used as were identical to those in Experiment 1, but Experiment 2 the criterion for statistical significance. Next, two different

1508 Protein requirement of growing blue-breasted quail

12.13-160 n=23 60.00 12.13-190 n=24 12.13-220 n=30 50.00 12.13-250 n=30 12.13-280 n=29 13.39-160 n=23 40.00 13.39-190 n=23 13.39-220 n=25 13.39-250 n=30 30.00 13.39-280 n=29 Weight (g per bird) 20.00

10.00

0.00 012345678 Age (week)

Figure 1 The growth curve of blue-breasted quails from 0 to 8 weeks of age (Experiment 1). statistical models were used to test whether relationships on weight more rapidly in this period and then laid their first between doses (dietary CP levels and CP intake) and eggs around 8 weeks of age (Figure 2). The BWs of the males responses (weight gain and feed efficiency) were fitted to a and females were approximately 49.4 6 4.4 and 65.5 6 broken linear pattern, a curvilinear pattern, or both. If the 6.8 g, respectively, at 8 weeks of age. Therefore, quails given relationship was suitable to the broken linear plateau, the diets with only 160 or 190 g/kg CP, regardless of ME con- minimum requirement of dietary CP for the best performance centration, grew more slowly in their first 4 weeks than was identified according to a one-slope quadratic broken- between 4 and 8 weeks of age, and no female laid an egg line model (Morris, 1999; Robbins et al., 2006) by SAS before the end of this experiment (Figure 1). (2002). Its equations were: The effects of the different combinations of ME and CP on growth responses for weeks 1 to 4 and weeks 5 to 8 are Y ¼ L þ UðRXÞ if XoR and Y ¼ L if XXR; presented in Table 3; the only interaction existed in weight gain between ME and CP levels for weeks 1 to 4 (P , 0.05). in which L and R represented the Y and X coordinate, In both ME groups, quails receiving CP of 160 g/kg showed respectively, of the point of inflection, and U was the slope the least weight gains (P , 0.05). Less weight gains of the oblique regression line before the inflection point. (P , 0.05) were observed in quails ingesting CP of 190 g/kg However, if the relationship also satisfied the curvilinear one, compared with those consuming higher CP concentrations in the maximum requirement of dietary CP for the best per- both ME treatments. No differences (P . 0.05) existed in formance, the inflection point of the curve was calculated by weight gain between the ME groups in which quails ingested conducting quadratic curvilinear regression (Morris, 1999) by CP of 250 and 280 g/kg, whereas quails consuming CP SAS (2002), and the equation was: of 220 g/kg with an ME of 13.39 MJ/kg had smaller weight gain than did those ingesting higher CP concentrations Y ¼ aX2 þ bX þ c: (P , 0.05). Of quails treated with the CP concentration of 220 g/kg, no difference existed between the ME treatments Results (P . 0.05). Similar weight gains were observed between Experiment 1 those consuming CP of 220 g/kg with an ME of 12.13 MJ/kg Since a total of 34 birds died during weeks 1–4, the final and those ingesting CP of 280 g/kg in both ME levels. number of quails treated with the CP concentrations of 160, Of main effects for weeks 1–4, quails treated with an ME 190, 220, 250 and 280 was 23, 24, 30, 30 and 29 in groups of 12.13 MJ/kg consumed more feed than did those receiving receiving 12.13 MJ/kg and 23, 23, 25, 30 and 29 in groups another ME level, whereas quails in both ME treatments treated with 13.39 MJ/kg, respectively. The growth curve of showed similar feed efficiencies. Although groups given CP BBQ from 0 to 8 weeks of age is presented in Figure 1. The of 250 g/kg showed the best-feed efficiency, there was no growth of most quails receiving CP of more than 220 g/kg in difference (P . 0.05) between these groups and those fed both ME treatment groups started slowly, accelerated and CP of 280 g/kg. Similar feed efficiencies were observed slowed again. After 4 weeks of age, quail gender could be between quails receiving CP of 220 and 280 g/kg, whereas distinguished by appearance. The males slowly increased in differences (P , 0.05) existed between those treated with BW between 6 and 8 weeks of age, whereas the females put CP of 190, 220 and 250 g/kg. Quails receiving CP of 160 and

1509 Wei, Hsieh, Chang, Chiu, Huang and Lin

Female 70 12.13-220 n=12 60 12.13-250 n=14 12.13-280 n=13 13.39-220 n=14 50 13.39-250 n=17 13.39-280 n=14 40

30 Weight (g per bird)

20

10

0 012345678 Age (week)

Male 70 12.13-220 n=18 60 12.13-250 n=16 12.13-280 n=16 50 13.39-220 n=11 13.39-250 n=13 13.39-280 n=15 40

30 Weight (g per bird) 20

10

0 012345678 Age (week)

Figure 2 The growth curve of blue-breasted quails of different genders that received dietary protein of more than 22% from 0 to 8 weeks of age (Experiment 1).

190 g/kg showed similar feed efficiencies (P . 0.05). For for weeks 1 to 4 were 295 g/kg with an ME of 12.13 MJ/kg weeks 5 to 8, no difference (P . 0.05) in weight gain, feed and 294 g/kg with an ME of 13.39 MJ/kg for the highest intake and feed efficiency was seen, regardless of ME levels, weight gain, and 295 g/kg for the best feed efficiency. No and no interaction existed between ME and CP levels. Quails estimate could be made for weeks 5 to 8 due to the varia- receiving CP of 190 g/kg had the greatest weight gains bility of the data. (P , 0.05); however, no difference (P . 0.05) existed between the other groups. Groups receiving 160 g/kg ate less feed (P , 0.05) compared with others whose intake was similar. Experiment 2 Quails consuming 160 and 190 g/kg showed similar feed Since a total of five birds died during the experiment, the efficiencies (P . 0.05), but better (P , 0.05) than others final number of quails treated with the CP concentrations of whose feed efficiencies were similar. 210, 220, 230, 240 and 250 was 28, 29, 30, 30 and 30 in The CP requirements estimated by the one-slope quadratic groups receiving 11.51 MJ/kg and 30, 30, 30, 29 and 29 in broken-line model (minimum) and quadratic curvilinear groups treated with 12.13 MJ/kg, respectively. The effects of regression (maximum) according to weight gain or feed the different combinations of ME and CP on growth perfor- efficiency for weeks 1 to 4 and 5 to 8 are shown in Table 4. mance are presented in Table 5. There were no interactions For the highest weight gain in weeks 1 to 4, the minimum CP (P . 0.05) between ME and CP levels in any of the four requirement was estimated to be 251 g/kg with an ME of indices. Significance also did not exist in any of the four 12.13 MJ/kg and 245 g/kg with an ME of 13.39 MJ/kg. For indices (P . 0.05) between dietary CP treatments. Quails the best feed efficiency, the minimum CP requirement was given diets with 11.51 MJ/kg exhibited better final BWs, calculated to be 256 g/kg for weeks 1 to 4. The maximum CP weight gains, feed intake and feed efficiency than did those requirements estimated by quadratic curvilinear regression that received 12.13 MJ/kg (P , 0.05).

1510 Protein requirement of growing blue-breasted quail

Table 3 The effects of the combinations of dietary metabolisable energy and protein on the growth responses of blue-breasted quailsy for weeks 1 to 4 (Experiment 1) Weeks 1 to 4 Weeks 5 to 8

Weight gain Feed intake Feed efficiency Weight gain Feed intake Feed efficiency ME (MJ/kg) CP (g/kg) n (g/quail) n (g/quail) n (gain/intake) n (g/quail) n (g/quail) n (gain/intake)

160 23 7.7e 3 74.9 3 0.102 23 23.6 3 210.5 3 0.098 190 24 12.4d 3 104.1 3 0.118 24 26.0 3 294.9 3 0.090 12.13 220 30 32.1bc 3 160.3 3 0.201 30 20.2 3 306.2 3 0.055 250 30 35.8a 3 158.6 3 0.227 30 17.4 3 323.7 3 0.052 280 29 34.0ab 3 172.3 3 0.200 29 20.0 3 313.5 3 0.052 160 23 6.1e 3 66.6 3 0.092 23 19.0 3 170.0 3 0.096 190 23 13.1d 3 104.3 3 0.128 23 26.0 3 308.8 3 0.097 13.39 220 25 28.6c 3 151.0 3 0.192 25 20.7 3 323.9 3 0.067 250 30 35.7a 3 143.8 3 0.249 30 18.4 3 310.9 3 0.054 280 29 34.8ab 3 165.4 3 0.213 29 22.5 3 332.9 3 0.058 Pooled s.e. 2.26 13.95 0.032 2.36 48.04 0.019 Main effects ME 12.13 136 25.2 15 134.0* 15 0.170 136 21.2 15 289.7 15 0.069 13.39 130 24.9 15 126.3 15 0.175 130 21.2 15 289.3 15 0.074 Pooled s.e. 0.48 3.76 0.008 1.00 12.70 0.005 160 46 7.0D 6 70.8D 6 0.097C 46 21.4B 6 190.3B 6 0.097A 190 47 12.7C 6 104.2C 6 0.123C 47 26.0A 6 301.9A 6 0.093A CP 220 55 30.5B 6 155.7AB 6 0.196B 55 20.4B 6 315.0A 6 0.061B 250 60 35.7A 6 151.2B 6 0.238A 60 17.9B 6 317.3A 6 0.053B 280 58 35.0A 6 168.7A 6 0.207AB 58 21.3B 6 323.2A 6 0.055B Pooled s.e. 1.94 8.33 0.019 1.97 28.71 0.011 Probability (P ) ME 0.15 0.04 0.54 0.88 0.97 0.31 CP ,0.01 ,0.01 ,0.01 ,0.01 ,0.01 ,0.01 ME 3 CP 0.03 0.76 0.66 0.25 0.48 0.92

ME 5 metabolisable energy. yThe number of total observations for female and male was 132 and 134, respectively. a–eMeans of ME–CP treatments within a column followed by different superscripts were significantly different (P , 0.05). A–DMeans of CP treatments within a column followed by different superscripts were significantly different (P , 0.05). *Significantly different from that of the other ME level (P , 0.05).

Table 4 The requirements of crude protein for blue-breasted quails for distinguish requirements at different growth stages (NRC, weeks 1 to 4 and 5 to 8 (Experiment 1) 1994). In this study, the fastest growth (g/day) of quails Protein requirement (g/kg) receiving dietary protein more than 220 g/kg occurred in week 2, followed by weeks 3 and 4; 5; 1; 6 and 8; and 7

Minimum- Maximum-- (i.e. a slow initial growth rate was followed by an accelerated growth phase, and the growth rates then slowed; Figure 1). Week Weight gain Feed efficiency Weight gain Feed efficiency The increase in BW in females in week 8 was due to the rapid a a development of the ovaries and oviducts in preparation for 1 to 4 251 256 295 295 245b 294b the beginning of laying (Figure 2). Bernstein (1973) observed 5to8––––that BBQ growth was slow from 4 to 9 days of age, pro- ceeded almost linearly until 4 to 5 weeks of age, and then ME 5 metabolisable energy. decelerated. Pis and Lus´nia (2005) showed the changes in aDietary ME: 12.13 MJ/kg. bDietary ME: 13.39 MJ/kg. BBQ growth using Gompertz curves. Slow initial growth

-Computed by a 1-slope quadratic broken-line model. -- followed by fast development was also observed in their Computed by quadratic curvilinear regression. study; growth began to slow after 25 days of age. These reported growth trends were confirmed in this study. In Discussion addition, a difference in mature BWs between males and For animals to achieve their full growth potential, it is females was noted by Prinzinger et al. (1993), Pearson necessary to provide them with sufficient nutrients. As (1994), Pis and Lus´nia (2005), and this study. As changes in nutrient requirements change with age, it is important to linear growth occurred between 4 and 5 weeks of age, the

1511 Wei, Hsieh, Chang, Chiu, Huang and Lin

Table 5 The effects of combinations of dietary metabolisable energy and protein on the growth responses of blue-breasted quailsy for weeks 1 to 4 (Experiment 2) ME (MJ/kg) CP (g/kg) P-value 11.51 12.13 Pooled s.e. 210 220 230 240 250 Pooled s.e. ME 3 CP n1- 147 148 58 59 60 59 59 4-week-old BW (g) 41.9* 38.5 0.40 40.5 39.8 39.7 40.2 40.8 0.62 0.85 Weight gain (g) 37.3* 33.8 0.38 35.8 35.1 35.1 35.6 36.1 0.60 0.87 n2-- 1515 66666 Feed intake (g) 147.4* 139.8 2.70 149.2 140.9 137.6 149.8 140.6 3.47 0.17 Feed efficiency (gain/intake) 0.25* 0.24 0.004 0.24 0.25 0.25 0.24 0.26 0.004 0.85

ME 5 metabolisable energy. yThe number of total observations for female and male was 146 and 149, respectively. -Sample size for BW and weight gain.

-Sample- size for feed intake and feed efficiency. *Significantly different from that of the other ME level (P , 0.05). growth stage was divided into two periods: weeks 1 to 4 requirements for weeks 5 to 8 could not be computed by and 5 to 8. either the broken-line or the quadratic model. Although CP requirements could be estimated for each In Experiment 2, requirements on the basis of ME con- week from data collected weekly, it would be time and centrations of 11.51 and 12.13 MJ/kg were estimated for labour consuming to mix a different diet for each week. birds from 0 to 4 weeks of age. The best weight gain and Furthermore, in practice, a single dietary CP concentration is feed efficiency were achieved when the dietary CP level was normally recommended for several weeks. For example, a CP more than 210 g/kg. By combining data from Experiments 1 concentration of approximately 250 g/kg in starter diets for and 2, both minimum and maximum protein intakes for the Japanese quails was reported (Weber and Reid, 1967; Vogt, best growth performance were estimated by the one-slope 1967; Lepore and Marks, 1971), and a concentration of quadratic broken-line model and quadratic curvilinear 200 g/kg CP was considered suitable for females from 3 to 6 regression, respectively (Figure 3). These were 17.74 and weeks of age (Vogt, 1967; Groop and Zucker, 1969). How- 20.22 g/MJ and corresponded to dietary CP levels of 204 and ever, NRC (1994) recommended only 1 dietary CP con- 233 g/kg when the ME concentration was 11.51 MJ/kg. The centration, 240 g/kg, for the whole growing period. In main reason for the large scatter observed in the data points Experiment 1, individual CP requirements were very similar presented in Figure 3 is not due to the different ratios of in the first 4 weeks so that the CP requirement was recal- males and females in the different cages, because Gompertz culated for weeks 1 to 4. As interaction existed in weight growth curves fitted for males and females were very close gain between ME and CP levels, the CP requirements were before 4 weeks of age in the report by Pis and Lus´nia (2005) estimated on the basis of the respective ME. The require- and a similar situation in real growth curves was observed in ments estimated by the one-slope quadratic broken-line this study (Figure 2). After calculation of the coefficient of model represented the minimum doses needed to achieve variation for each treatment in Experiments 1 and 2, the the best response, that is, it is not necessary to provide more resultant large scatter is probably attributable to less uni- than 245 g/kg CP when an ME of 13.39 MJ/kg is provided to formity in quail growth from 0 to 4 weeks of age in the same quails from 0 to 4 weeks of age. With regard to the higher CP treatment. Although the means of BWs for 30 quails requirements computed by quadratic curvilinear regression between treatments were very similar in the beginning, the and representing the maximum doses required to obtain range of the coefficient of variation for treatments was 8.9% the best response, Vedenov and Pesti (2008) pointed out to 12.0%, and a more severe phenomenon of 5.9% to 24.3% that the minimum requirement would be chosen if it was was observed in the end. As the BBQ is a new experimental important to avoid wasting dietary CP, whereas use of animal model, unlike the many pure breeds and lines of the maximum requirement would ensure that quails receive experimental rats or mice, less uniformity in growth should sufficient dietary CP. In this study, the minimum requirement be overcome by breeding in the future. results of the weight gain and feed efficiency indices were In Experiment 2, the quails given diets containing similar; this similarity was also observed in Japanese quails 11.51 MJ/kg performed better in terms of both weight gain (Weber and Reid, 1967), Bobwhite quails (Wilson et al., 1977) and feed efficiency (P , 0.05) than did those receiving and broilers (Sebastian et al., 1997). As BWs approached 12.13 MJ/kg. In Experiment 1, significance did not exist in mature values after week 5, the weekly weight gains of both of the indices (P . 0.05) between the dietary treat- quails fed dietary CP of more than 220 g/kg slowed down. ments of 12.13 and 13.39 MJ/kg. Therefore, it can be con- Furthermore, in most cases, weekly weight gains were even cluded a dietary ME concentration of 11.51 MJ/kg is more smaller than in those receiving 160 or 190 g/kg CP. Thus, CP appropriate for BBQ from 0 to 4 weeks of age.

1512 Protein requirement of growing blue-breasted quail

(a) y 30

20

10

0

Y = 19.58 – 2.62 (17.74 - X) , X < 17.74 –10

Weight gain (g/MJ) gain Weight Y = 19.58, X 17.734 –20 R2 = 0.70

–30 0102030 x Protein intake (g/MJ)

(b) y 30 20 10 0 –10 –20 Y = -0.23X 2 + 9.48X – 76.76 –30 R 2 = 0.69 –40

Weight gain (g/MJ) gain Weight –50 –60 –70 –80 0102030 40 x Protein intake (g/MJ)

Figure 3 The regressions of the weight gain of blue-breasted quails on dietary protein levels by broken-line (a) and quadratic (b) models for 0 to 28 days of age. Average cage values for BW and feed intake were used for regression between weight gain and CP intake so that total observations were 60.

In summary, it is not necessary to provide BBQ with very high Bernstein MH 1971. Cutaneous and respiratory evaporation in the painted quail, CP diets, such as turkey starter feed, that contain approximately Excalfactoria chinensis, during ontogeny of thermoregulation. Comparative 300 g/kg CP (Bernstein, 1971); they can achieve good perfor- Biochemistry and Physiology Part A: Physiology 38, 611–617. Bernstein MH 1973. Development of thermoregulation in painted quail, mance with dietary CP of more than 204 g/kg on the basis of an Excalfactoria chinensis. Comparative Biochemistry and Physiology Part A: ME of 11.51 MJ/kg for weeks 1 to 4. Physiology 44, 355–366. Groop J and Zucker H 1969. Untersuchungen zum protein bedarf der Japanischen wachtel wa¨hrend der Aufzucht. Arch f Geflugelk 32, 337–342. Acknowledgements Lepore PD and Marks HL 1971. Growth rate inheritance in Japanese quail. 5. The authors wish to thank Mr. Jeng-Chi Huang for his kindly Protein and energy requirements of lines selected under different nutritional help to take care of BBQ breeders and hatch eggs. environments. Poultry Science 50, 1335–1341. Lo˜ hmus M and Sundstrom LF 2004. Leptin and social environment influence therisk–taking and feeding behaviour of Asian . Animal Behaviour 68, References 607–612. Andersson S, Uller T, Lo˜ hmus M and Sundstrom F 2004. Effects of egg yolk Lo˜ hmus M, Sundstrom LF and Silverin B 2006. Chronic administration of leptin testosterone on growth and immunity in a precocial bird. Journal of Evolutionary in Asian blue quail. Journal of Experimental Zoology Part A: Comparative Biology 17, 501–505. Experimental Biology 305, 13–22. Association of Official Analytical Chemists 2000. Official methods of analysis, Morita Y, Maruyama S, Hashizaki F and Katsube Y 1999. Pathogenicity of 17th edition. AOAC International, Gaithersburg, MD, USA. mycobacterium avium complex serovar 9 isolated from painted quail (Excalfactoria chinensis). Journal of Veterinary Medical Science 61, 1309–1312. Askew GN and Marsh RL 2001. The mechanical power output of the pectoralis muscle of blue-breasted quail ( chinensis): the in vivo length cycle and Morris TR 1999. Dose-response trials. In Experimental design and analysis in its implications for muscle performance. Journal of Experimental Biology 204, animal sciences (ed TR Morris), pp. 78–92. CABI Publishing, New York, USA. 3587–3600. National Research Council (NRC) 1994. Nutrient requirements of poultry, 9th Askew GN and Marsh RL 2002. Review: muscle designed for maximum short-term edition. National Academy Press, Washington, DC, USA. power output: quail flight muscle. Journal of Applied Physiology 205, 2153–2160. Ono T, Nakane Y, Wadayama T, Tsudzuki M, Arisawa K, Ninomiya S, Askew GN, Marsh RL and Ellington CP 2001. The mechanical power output of Suzuki T, Mizutani M and Kagami H 2005. Culture system for embryos of the flight muscles of blue-breasted quail (Coturnix chinensis) during take-off. blue-breasted quail from the blastoderm stage to hatching. Experimental Journal of Experimental Biology 204, 3601–3619. Animals 54, 7–11.

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Pearson JT 1994. Oxygen consumption rates of adults and chicks SAS Institute 2002. SAS/STAT User’s Guide Version 6, 5th edition. SAS Institute during brooding in (Coturnix chinensis). Journal of Comparative Inc., Cary, USA. Physiology B: Biochemical, Systems, and Environmental Physiology 164, Sebastian S, Touchburn SP, Chavez ER and Lague PC 1997. Apparent digestibility 415–424. of protein and amino acids in broiler chickens fed a corn-soybean diet Pis Tand Lus´nia D 2005. Growth rate and thermoregulation in reared king quails supplemented with microbial phytase. Poultry Science 76, 1760–1769. (Coturnix chinensis). Comparative Biochemistry and Physiology Part A: Tsudzuki M 1994. Excalfactoria quail as a new laboratory research animal. Molecular & Integrative Physiology 140, 101–109. Poultry Science 73, 763–768. Pond WG, Church DC, Pond KR and Schoknecht PA 2005. Protein and amino Vedenov D and Pesti GM 2008. A comparison of methods of fitting several acid. In Basic animal nutrition and feeding, 5th edition (ed. WG Pond, DC models to nutritional response data. Journal of Animal Science 86, 500–507. Church, KR Pond and PA Schoknecht), pp. 113–143. John Wiley and Sons, Inc., Hoboken, New Jersey, USA. Vogt H 1967. Weitere versuche u¨ ber den eiweissbedarf der wachtelku¨ ken im zweiten abschnitt der aufzucht. Arch Fur Geflugelk 31, 211–222. Prinzinger R, Misovic A and Schleucher E 1993. Energieumsatz und ¨ ¨ ko¨ rpertemperatur bei der Zwergwachtel (Coturnix chinensis) und beim Weber CW and Reid BL 1967. Protein requirements of coturnix quail to five Bindenlaufhu¨ hnchen (Turnix suscitator). Journal of Ornithology 134, 79–84. weeks of age. Poultry Science 46, 1190–1194. Robbins KR, Saxton AM and Southern LL 2006. Estimation of nutrient require- Wilson HR, Douglas CR and Nesbeth WG 1977. Feed consumption and protein ments using broken-line regression analysis. Journal of Animal Science 84 efficiency by Bobwhite quail in response to dietary energy levels. Poultry Science (Suppl), E155–E165. 56, 1127–1129.

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