Materials and methods

SODIUM BICARBONATE IN POULTRY NUTRITION

INTRODUCTION • Poultry industry in recent years has occupied a leading role in many parts of the world since it has undergone very rapid development. • The potential for further growth is obvious in view of the nutritional value of meat and eggs. • The continuos demand for an improved productive level forced many to use nutritional manipulations both in thermoneutral conditions as well as in high temperatures and humidity conditions.

INTRODUCTION • Among these nutritional manipulations is the electrolyte supplementation to maintain a correct plasma acid-base balance in order to improve the productive performance of poultry. • Sodium bicarbonate is a cheap salt that is widely available and its beneficial effect is confirmed by many (Teeter et al., 1985; Bonsembiante et al., 1986, 1988, 1989, 1990; Whiting et al., 1991).

OBJECTIVES A series of trials were performed to evaluate the effect of different levels of sodium bicarbonate on the productive performance, physiological response and meat quality of turkeys, broilers and guinea fowls.

Trial performed on turkey meat production • Bird’s rearing conditions • 145 male turkeys, 60 d, (B.U.T. Big 6, 4.9 kg). • 2 experimental groups in 14 pens (density 0.5 m2/bird), (10 or 11 bird/pen). • Two diets, Control T(0%) and B (2%) of NaHCO3. • From July to October into 3 periods (4wks/period).

Materials and methods • Temp. and humidity (L.S.I, TIGH-1 TH). • Light intensity (Delta OHM HD 8366).

• Ammonia concentration (Dragher pump). • Body weight, feed intake and health status. • Diet and water analysis.

Materials and methods • Physiological measurements and blood sampling, Hitachi-911 (Boehringer Mannheim). • Slaughtering yields and carcass composition. • pH (Delta ohm) and color measurements (Minolta CR-300 colorimeter). • Drip loss (after freezing, -20° C), 250 g meat.

• Cooking loss. • Shear force, Warner-Bratzer Shear Device (INSTRON).

Experimental conditions • Water Characteristics: – – – – –

pH Conductibility K Na Cl

6.85 ± 0.07. 315 ± 6.4 µS/cm-20 ° C. 1.1 ± 0.03 mg/l. 3.8 ± 0.03 mg/l. 5.0 ± 0.08 mg/l.

Environmental conditions – Temperature 25.2±2.4°C. – Relative humidity 82.6-91.7%.

Average temperature (°C) recorded during the turkeys trial

Temp.

28 26

8

24

16

hrs

22

24

20 I 25.2 ±2.4ºC

II

III Periods

Whole

Whole day

Humidity %

Average humidity % recorded during turkeys trial 8

95 90

16

85

hrs

24

80 75 I

82.6-91.7%

II

III

Periods

Whole

Whole day

Ingredients (%) of the experimental diet I period T1

II period B1

T2

B2

Corn meal

38.89 37.14 47.58 45.83

Soybean meal (50% N6.25) Triticum wheat

30.70 30.70 23.40 23.40

NaHCO3 NaCl

11.00

11.00 11.00

11.00

-

2.00

-

2.00

0.15

0.15

0.15

0.15

Chemical composition of the diet (% on as fed basis) - Crude protein (N6.25) MJ/kg - ME - Lysine - DL-Methionine - Ca - P - Na - K - Cl dEB (Na++K+-Cl-) meq/100gm

T1

B1

T2

B2

24.17

24.01

20.11

19.95

13.41 1.57 0.71 1.08 0.74 0.13 0.76 0.18 23.5

13.16 1.56 0.71 1.15 0.69 0.21 0.74 0.16 44.2

14.12 1.23 0.56 1.11 0.71 0.29 0.71 0.19 20.3

13.87 1.04 0.41 1.07 0.75 0.35 0.73 0.20 40.1

Turkeys productive performance Control (T)

Bicarbonate (B)

4971 9690 168a 278 1.67A

4877 9729 173 273 1.59B

14463 18615 143b 360b 2.52

14650 19082 153a 391a 2.56

I period (0-28) Initial weight Final body weight Growth rate Feed intake Feed conversion ratio

g g g/d g/d g/g

III period (56-85) Initial weight g Final body weight g Growth rate g/d Feed intake g/d Feed conversion ratio g/g

A, B, : P