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Effect of tomato waste meal supplementation on laying performance and egg quality of white leghorn chickens

Kemer Yimam Ahmed, Mengistu Urge1, Shalu Kumar and Negasi Ameha1

Department of Animal and Range Science, College of Agriculture, Bule Hora University, Bule Hora- Ethiopia, Post Box -144
shalukumar18@rediffmail.com
1 Department of Animal and Range Science, College of Agriculture, Haramaya University, Haramaya - Ethiopia Post Box - 138

Abstract

The experiment was conducted at Poultry Unit, Haramaya University, Haramaya, Ethiopia to determine the effect tomato waste meal supplementation on laying performance and egg quality of white leghorn chickens. In this experiment, 180 white leghorn layers (41 weeks old age and average body weight of 1.500.13 kg) were allocated into five experimental groups viz., TWM0 (basal diet+ 0.0 % tomato waste meal), TWM6.5 (basal diet+ 6.5 % TWM), TWM13 (basal diet+ 13.0 % TWM), TWM19.5 (basal diet+ 19.5 % TWM), and TWM26 (basal diet+ 26.0 % TWM) with three replications and each replication have 12 layers. During the experimental period, data on dry matter intake (DMI), body weight change (BWC), hen-day egg production (HDEP), hen-housed egg production (HHEP), feed conversion ratio (FCR), feed conversion efficiency (FCE), egg mass (EM), egg weight (EW) and egg quality traits were analysed. The groups fed TWM0, TWM6.5, TWM13 and TWM19.5 had better feed intake (97.50 g, 98.30 g, 98.90 g and 99.6 g/day/h, respectively) compared with TWM26 (95.4 g/day/h) diets. The HDEP was significantly (p<0.001) higher in TWM19.5 (65.5%) followed by TWM13 (59.97%), TWM6.5 (58.40%), TWM0 (56.60%) and TWM26 (55.2%). No mortality was recorded throughout the duration of the study. Egg mass increased with increasing levels of TWM in the layer ration up to 19.5% while, it was decreased (p<0.05) at 26% TWM inclusion. Egg weight did not show significant (p>0.05) difference among treatments. The feed conversion ratio was better ( p<0.05) in TWM19.5 (2.8) than TWM0 (3.2), TWM6.5 (3.1), TWM13 (3.1) and TWM26 (3.2). The egg geometric traits i.e., albumen index, albumen ratio, yolk height, yolk weight, yolk index, yolk ratio, egg shape index, egg surface area and egg volume were not significantly different (P>0.05) among treatments. However, yellow yolk colour intensity increased (p<0.001) with increasing inclusion level of TWM. In conclusion, TWM can be used as an alternative feedstuff for laying hens at inclusion levels up to 26% without any negative impact on performance and egg quality traits.

Keywords: egg quality, growth rate, feed intake, white leghorn


Introduction

Livestock is an integral feature of the Ethiopian agriculture industry. Its contributed 20.7 percent of agricultural GDP (FAO 2019). Ethiopia is the second most populous nation in Africa, after Nigeria, with a population of about 104.9 million growing at a rate of about 2.5 percent annually. A recent survey of several countries found that 59 percent of the people surveyed in sub-Saharan Africa (SSA) was suffering from severe energy deficiency (Smith and Wiseman, 2007). Poultry is an important part of an integrated food production/security framework for the majority of sedentary populations in Sub-Saharan Africa. The chicken meat and eggs are the best source of quality protein, and are badly needed by the many millions of people who live in poor nutrition, inadequate nutrition, and poverty.

Chickens are widely reared in Ethiopia and total population of chicken is estimated to be about 57.499 thousand (FAO 2019) regarding breed, 54.060 thousand (90.86%), 2.606 thousand (4.53 %) and 2.833 thousand (4.92%) of the total poultry were reported to be indigenous, exotic and hybrid/crossbred birds, respectively. The estimate of total number of eggs produced during the year is about 54.00 thousand tons (FAOSTAT 2018). Indigenous flocks are slow in growth rates and very poor in egg productivity. Mean body weights at 8 and 16 weeks of age could be as low as 242 and 621 g, respectively (Nigussie 2011). The mean annual egg production does not exceed 60 eggs/hen. Despite their lower productivity, indigenous birds are still the major suppliers of poultry products in Ethiopia. They are well adapted to their environments, resistant to diseases, can scavenge for food, and are able to avoid predators as they are agile and fast, with the colour and patterns of their feathers providing natural camouflage. The productivity of indigenous poultry chicken would be improving through scientific management, feeding and healthcare practices. Therefore, the present experiment “effect of tomato waste meal supplementation on laying performance of white leghorn chickens was planned to search alternative feed resources.


Materials and methods

Description of the experimental site and location

The experiment was conducted at Poultry Farm, Haramaya University Ethiopia. The university was located in east at about 515 km away from Addis Ababa on 42 3΄ E longitude, 9 26΄ N latitude and an altitude of 1980 m above sea level. The mean annual rainfall of the area is 780 mm and the average minimum and maximum temperature are 8C and 24C, respectively (Mishra et al 2004).

Experimental design and feed formulation

A total of 180 white leghorn layers (41 weeks old) were obtained from Poultry Farm, Haramaya University with uniform size and similar age. Then experimental birds were allotted in to five dietary treatments viz., TWM0 (basal diet+ 0.0 % tomato waste meal), TWM6.5 (basal diet+ 6.5 % TWM), TWM13 (basal diet+ 13.0 % TWM), TWM19.5 (basal diet+ 19.5 % TWM), and TWM26 (basal diet+ 26.0 % TWM) with three replications and each replication have 12 layers.

Feed materials were procured from local market in row form. Tomato waste meal was prepared by spreading the fresh tomato waste on plastic sheet on ground and dried for a day in a direct sun light. Then, it was dried for an extra 5 to 6 days under shade with good ventilation. After proper dried, tomato waste meal grinded by hummer milled. The proximate compositions of tomato waste meal and other feed materials are shown in Table 1.

Table 1. The proximate compositions of Tomato waste meal and other feed materials

Parameters (%)

Feed Ingredients

Maize

TWM

WS

NSC

SBM

GNC

BMM

Dry matter

88.5

91.0

95.0

93.0

94.0

92.0

94.0

Crude protein

8.13

18.65

15.13

31.1

38.0

33.9

50.15

Crude fibre

2.9

28.0

12.5

17.9

11.8

7.5

0.93

Ether extract

4.3

9.24

2.3

5.1

4.5

8.24

10.27

Ash

6.93

5.16

6.3

7.8 2

9.5

7.6

44.3

Nitrogen free extract

66.24

29.95

58.77

31.17

30.2

34.76

11.65

Ca

0.05

0.53

0.08

0.36

0.2

0.19

10.3

P

0.20

0.62

0.17

0.30

0.38

0.58

5.1

ME (kcal/kg)

3645

1760

2710

2206

2760

3424

2620

TWM = Tomato waste meal, WS = Wheat short, NSC= Nuge seed cake, SBM= Soybean meal, GNC = Groundnut cake meal, BMM= Bone and Meat meal
Management of experimental birds

Before arrival of experimental birds; pens, watering and feeding troughs were cleaned, disinfected. In pens each with a size of 2 m x 2.5 m. The litter material used was wood shavings and hay. On the first day (after one week adaptation period) of the start of the experiment, layers were provided water with vitamin premix (15 mm vitamin premix in 10 litter water). On the second day of the experiment, layers were vaccinated against Newcastle disease and medications provided using broad spectrum antibiotics. The birds were intensively raised on deep litter system for twelve weeks starting from the actual time of data collection. Feed was offered to the layers every day in to two equal parts through ad libitum.

Chemical composition of experimental feed

The chemical composition of ration is presented in Table 2. The experimental ration was formulated on an iso-caloric and iso-nitrogenous basis in such a way to consist 2750 to 2900 kcal ME per kg DM and 16.5 to 17.00 percent CP (NRC 1994). Ration was formulated by using feed win interactive software and excel based on layer metabolic energy and crude protein requirement. The chemical properties of ration were analysed (AOAC 1990).

Table 2. Proportion of ingredients (%) used in formulating the experimental rations

Ingredients

Treatments

TWO

TWM6.5

TWM13

TWM19.5

TWM26

Maize

43.6

45.4

52.0

50.0

50.0

Wheat short

18.5

15.0

2.0

0.5

0.0

NSC

15.0

5.5

2.50

0.5

0.5

SBM

7.0

15.0

18.0

14.0

8.5

GNC

6.0

3.0

3.0

4.5

0.5

BMM

2.0

2.0

2.0

3.5

8.0

GLP

0.50

0.50

0.50

0.50

0.5

HCL- Lysine

0.25

0.25

0.25

0.25

0.25

Methionine

0.13

0.13

0.13

0.13

0.13

DCP

0.50

0.50

0.50

0.50

0.50

Limestone

5.50

5.50

5.50

5.50

5.50

Salt

0.50

0.50

0.50

0.50

0.50

TWM

0.00

6.50

13.0

19.50

26.0

Total

100.0

100.0

100.0

100.0

100.0

ME (Kcal/kg)

2890

2873

2888

2823

2753

Crude protein

16.70

16.60

16.60

16.5

16.5

Crude fiber (%)

7.60

8.0

8.20

9.10

9.85

Calcium (Ca)

2.47

2.65

2.71

2.77

2.78

Phosphorus(P)

0.30

0.32

0.34

0.35

0.37

NSC = Nuge seed cake, SBM = Soybean meal, GNC = Groundnut cake, BMM = Bone and Meat meal, GLP = General layer premix, DCP = Di calcium phosphate, TWM = Tomato Waste meal ME = Metabolized energy

Data collection

The parameters recorded for evaluate the suitable level of tomato waste meal supplementation for production performance included final body weight, body weight gain, feed consumption, feed conversion ratio and survival rate. Feed intake was measured by subtracting the amount of refused from the amount offered on DM basis. Body weight was taken on weekly basis. The mean dry matter conversion ratio was measured as the amount of feed consumed per unit body weight gain as shown below. Feed conversion efficiency (FCE) was determined per replicate by dividing the egg mass with the weight of feed consumed.

Hen day egg production was worked using the following formula given by North (1978), Feed efficiency per dozens of eggs by Ahmad et al (2010), egg production was calculated by total number of eggs produced by hen divided by total number of hens live.

Statistical analysis

The experimental data were analyzed by the General Linear Model (GLM) procedure of the Statistical Analysis System (SAS) software (2002). The treatment means were compared using least significant difference (LSD) method to locate the treatment means that were significantly different. The model was used for statistical analysis.

ϒij = + ti + ɛij

Where ϒij = the response variable

ti = treatment effect

= over all mean

ɛij = random error


Results and Discussion

Growth performance of birds

The effect of tomato meal supplication on growth performance of birds are presented Table 3. The results showed that there was no significant (p>0.05) difference between experimental treatments for initial body weight, final body weight and body weight gain. In case of dail y feed intake and total feed intake had higher (p<0.001) in TWM19.5 group as 99.6 g/day/bird and 8366.4 g/bird as compared to TW0 and other treatment groups. The finding of present experiment is agreement with Salajegheh et al (2012). They were reported up to 19.0 percent inclusion of dried tomato pomace did not affect (p>0.05) body weight of birds. Nobakht and Safamehr (2007) also observed that 10.0 per cent dried tomato pomace had significant (p>0.05) affected body weight of layer. However, Mansoori et al (2008) reported similar results for body weight gain after inclusion of tomato pomace up to 10 and 15 percent, respectively. The non-significant results might be due to the nature of the birds feed conversion efficiency mechanism. In layers, more nutrients are converted into egg rather than muscle development, which can be confirmed by the fact that egg production increased, but body weight remained similar regardless of the level of TWM. Moreover, Calislar and Uygu (2010) observed increased body weight parallel to increased DTP inclusion level up to 20 per cent and attributed the increase to high fiber content of the diet that may increase dry matter feed intake when it does not exceed the maximum limit that hamper feed intake.

Table 3. Effect of tomato meal supplementation on growth rate of White Leghorn birds

Parameters

Treatments

SEM

p Value

LS

TWO

TWM6.5

TWM13

TWM19.5

TWM26

Initial body weight (kg/bird)

1.43

1.43

1.40

1.43

1.50

0.04

0.45

NS

Final body weight (kg/bird)

1.53

1.70

1.56

1.63

1.56

0.05

0.26

NS

Body weight gain (kg/bird)

0.10

0.26

0.13

0.27

0.066

0.05

0.07

NS

Daily feed intake (g/bird)

97.5bc

98.3ab

98.9ab

99.6a

95.4c

0.6

0.01

***

Total feed intake (g/bird)

8190bc

8257.2ab

8307.6ab

8366.4a

8013.6c

58.3

0.01

***

a, b, c row means with different superscripts are significantly different, *** = (P<0.001), ** = (P < 0.05)

Feed conversion ratio

The results of average feed conversion ratio of experiment are presented Table 4. The FCR of layers were significantly affected (p<0.05) by the level of tomato waste meal. The feed conversion ratio of white leghorn layers fed TWM19.5 diet was significantly lower (p<0.05) than TWM0, TWM6.5, TWM13 and TWM26. The figure 1 also showed that there was a slight improvement upto only TWM19.5 diet, however, addition of more tomato waste meal was also decreased feed conversion ratio. The feed conversion ratio recorded in the present experiment is higher than reported by Calislar and Uygu (2010) who reported 2.05 FCR in Lohman Brown layers fed diet containing up to 20 percent DTP. The FCR value of TWM19.5 in the current study is almost similar with that reported by Salajegheh et al (2012) for Lowman LSl-LITE layers (2.27) fed diet consisting up to 19 percent DTP. The higher dietary fiber in layers consumed ration containing 12 percent DTP could be explained by the highest amount of FCR since the main effect of dietary fiber is an increase in viscosity of digesta, high variability of feeding value, and amount of metabolizable energy in feed (Bedford and clason 1992).

Table 4. Effect of tomato meal supplementation on feed conversion ratio of White Leghorn birds

Parameters

Treatments

SEM

p Value

LS

TWO

TWM6.5

TWM13

TWM19.5

TWM26

Final body weight (kg/bird)

1.53

1.70

1.56

1.63

1.56

0.05

0.26

NS

Total feed intake (g/bird)

8190bc

8257.2ab

8307.6ab

8366.4a

8013.6c

58.3

0.01

***

Feed conversion ratio

3.20a

3.1a

3.1a

2.8b

3.2a

0.06

0.006

**

Feed conversion efficiency

0.30b

0.30b

0.3b

0.4a

0.30b

0.00

0.001

***

a, b, c row means with different superscripts are significantly different, *** = (P<0.001), ** = (P < 0.05)



Figure 1. The effect of tomato waste meal supplementation on feed conversion ratio
Egg performance of birds

The egg production performance of white leghorn birds fed tomato meal are presented in Table 5. The results of present study showed that there was significant difference (p<0.001) in hen day egg production between treatments. The higher (p<0.001) hen day egg production recorded in the TWM19.5 diet (65.5) as compared to TWM13 (59.97), TWM6.5 (58.40), TWM0 (56.60) and TWM26 (55.20). Moreover, in term of egg production/pen also maximum (p<0.001) recorded in TWM19.5 (660) followed by TWM13 (604.7), TWM6.5 (589), TWM0 (571) and TWM26 (556.3). However, TWM0, TWM6.5 and TWM26 were at par to each other. The figure 2 also presented that there was a slight improvement as the level of tomato waste was increased followed by a decline in performance with higher levels of tomato waste meal. The egg production of experimental birds improves due balanced nutrient supply by tomato waste meal. Tomato waste meal contains higher level of lysine, methionine and a combination of other amino acids, which supply the required amount of essential nutrients for better production (Mansoori et al 2008). AL Betawi (2005) also recorded positive correlation between methionine and lysine levels in the diets and egg production. But, Gregoriades et al (1984) reported non-significant differences in egg production among laying hens fed diets containing feed up to 15 percent dry tomato pomaces compared to control group. Dotas et al (1999) also reported non-significant effects on egg production of hens fed diets containing dry tomato pomaces (12.0%). The reason of decline in egg production at high level of inclusion in the present study was related to the value of fiber in these diets and consequently reduction in dry matter intake and digestibility of nutrient which in turn limits productivity. The egg mass of layer fed TWM19.5 was significantly higher (P<0.05) than TWM0, TWM6.5 and TWM26, except TWM13. The result on egg mass obtained in this study is in line with Nobakht and Safamehr (2007) who reported significantly higher (P<0.05) eggs mass in layers fed diet containing up to 15 percent and 10 percent DTP, respectively. The improvement in egg mass in layers fed diet containing 19.5 per cent TWM is due to the higher egg production. However, Salajegheh et al (2012) reported absence of significant difference in egg mass of layers consumed different inclusion levels of DTP up to 19 percent in the ration.

Table 5. Effect of tomato meal supplementation on production performance of White Leghorn birds

Parameters

Treatments

SEM

p Value

LS

TWO

TWM6.5

TWM13

TWM19.5

TWM26

Production performance traits

Number of egg production/pen

571c

589bc

604.7b

660a

556.3c

10.2

0.0003

***

Hen day egg production (%)

56.60c

58.4bc

59.97bc

65.5a

55.2c

1

0.0003

***

Egg mass

30.70bc

31.47cb

32.3ab

35.7a

29.5c

0.8

0.026

**

a, b, c row means with different superscripts are significantly different, *** = (P<0.001), ** = (P < 0.05)



Figure 2. The effect of tomato waste meal supplementation on hen day egg production

Egg quality traits

The egg geometric traits of experimental birds are presented Table 6. In present experiment, all external and internal parameters of egg i.e., egg length (cm), egg width (cm), egg volume (cm3), egg surface area (cm2), egg shape index, egg shell weight (g), egg shell thickness (mm), egg shell membrane thickness (mm), shell ratio, albumin weight (g), albumin height (mm), albumin index, albumin ratio, yolk weight (g) were recorded non-significant differences between treatments. However, yolk colour score significantly (P<0.001) better recorded in TWM26 (6.3) as compared to rest of treatments. The maximum egg weight was recorded in TWM0 (57.70 g) as compared to other experimental treatments. In accordance with the present study, Salajegheh et al (2012) and Habanabashaka et al (2014) reported non- significant difference (p>0.05) in egg weight when birds fed dry tomato pomaces up to 19.0 and 12.0 percent, respectively. Higher egg length recorded in both groups TWM0 and TWM19.5 as 5.40 cm, egg width in TWM6.5 (4.00 cm), egg volume in TWM0 (46.10 cm3), Egg Surface Area in TWM0 (64.50 cm2), Egg shape index in TWM6.5 (75.60), Egg shell weight in TWM13 (7.80 g), Albumin weight in TWM0 (32.80 g), Yolk weight in TWM13 (17.20 g) and Haugh Unit in TWM26 (90.40) as compared to other experimental treatments. However, yolk colour score significantly higher recorded in TWM26 (6.3) followed by TWM19.5 (5.6), TWM13 (4.9), TWM6.5 (4.6), TWM0 (3.5). The results of yolk colour are comparable with several authors Mansoori et al (2008), Calislar and Uygun (2010) Salajegheh et al (2012) who recorded a slightly higher yolk colour with increased level of dry tomato pomaces in layers diets. On the basis of overall results, inclusion of tomato waste meal in poultry diets were not affected egg quality traits except yolk colour.

Table 6. Effect of Tomato meal supplementation on egg performance of White Leghorn birds

Parameters

Treatments

SEM

p Value

LS

TWO

TWM6.5

TWM13

TWM19.5

TWM26

Egg quality traits

Egg weight (g)

57.70

53.83

53.77

54.20

54.53

0.70

0.87

NS

Egg length (cm)

5.40

5.30

5.30

5.40

5.30

0.04

0.16

NS

Egg width (cm)

3.90

4.00

4.00

4.00

4.00

0.50

0.88

NS

Egg volume (cm3)

46.10

45.8

45.6

47.20

45.30

1.01

0.73

NS

Egg Surface Area (cm2)

64.50

64.2

63.9

65.30

64.10

0.92

0.83

NS

Egg shape index

73.03

75.6

75.1

74.50

74.60

1.08

0.56

NS

Egg shell weight (g)

6.00

6.40

7.80

6.60

6.50

0.45

0.13

NS

Egg shell thickness (mm)

0.30

0.30

0.31

0.31

0.30

0.00

0. 09

NS

Shell membrane thickness (mm)

0.013

0.01

0.01

0.01

0.01

0.002

0.58

NS

Shell ratio

10.90

11.50

14.30

11.50

11.65

0.29

0.20

NS

Albumin weight (g)

32.80

32.70

31.10

33.30

32.70

1.0

1.00

NS

Albumin height (mm)

7.38

7.63

7.79

7.34

8.11

0.92

0.2

NS

Albumin index

9.60

10.30

10.90

9.60

11.10

1.10

0.6

NS

Albumin ratio

59.00

58.80

55.00

58.50

57.90

0.85

1.9

NS

Yolk weight (g)

16.70

16.40

17.20

16.80

17.13

0.23

0.18

NS

Yolk height (mm)

15.60

15.60

16.00

15.80

15.97

0.17

0.32

NS

Yolk index

40.90

41.80

43.10

41.10

42.80

0.77

0.23

NS

Yolk ratio

30.20

29.70

30.70

29.60

30.50

0.37

0.22

NS

Yolk colour score

3.5d

4.6c

4.9cb

5.6b

6.3a

0.23

0.01

***

HU

86.4

87.7

89

87.9

90.4

1.9

NS

a, b, c row means with different superscripts are significantly different, *** = (P<0.001), **=(p<0.05)


Conclusion


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