The effect of chicory root powder on growth performance and some blood parameters of broilers fed wheat-based diets

Abstract

The objective of this study was to examine the effect of the chicory root powder (CRP) on growth performance and some blood parameters in broiler chickens fed whole wheat (WW) or ground wheat (GW) based diets. A total of 240 one-day old (Ross 308) broiler chickens used in a completely randomised design (with 4 × 2 factorial arrangement), allocated to 8 treatments with 3 replicate and 10 birds per pen. Treatments were a combination of four levels of CRP (0%, 1.5%, 3%, 4.5%) and two forms of wheat grain (whole vs. ground). No differences were found for body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) between treatments during starter period (1–21 d). BWG of 4.5% CRP diet fed birds was significantly (p < 0.05) lower than that of control treatment during the growth (21–42 d) and whole trail period (1–42 d). FI and FCR in birds fed CRP diets were not significantly different compared to those of control (free CRP). Feeding WW compared to GW resulted in a significant increase in the relative weight of the gizzard. Feeding 4.5% CRP + GW decreased significantly triglyceride (TG) and very low-density lipoprotein (VLDL)– cholesterol levels, but the total cholesterol, low-density lipoprotein–cholesterol and high-density lipoprotein–cholesterol were not affected by dietary treatments. The results shown that feeding CRP up to 4.5% in GW-based diets significantly decreased TG and VLDL–cholesterol concentrations without adverse effects on broilers performance.

Keywords:

• chicory root powder
• performance
• blood parameters
• broilers
• wheat

1. Introduction

It is well known that the use of certain polysaccharides such as inulin that may have prebiotic effect is a possible way to improve intestinal health and animal performance in the absence of antibiotic growth promoter by stimulating and selective effect on the growth or activity, or both, of indigenous bifidobacteria and lactobacilli (Roberfroid and Delzenne 1998; Gibson and Fuller 2000). However, the results of inulin or Fructooligosaccharides (FOS) on the growth performance of poultry are inconsistent.

Inulin is naturally occurring indigestible carbohydrate that is found in plant sources and is most concentrated in chicory (Kubik et al. 2006). Although the beneficial effects of chicory type inulin on growth performance and production efficiency of broilers have been reported in some studies (Ammerman et al. 1988a, 1989; Yusrizal and Chen 2003; Kim et al. 2010), while other reports were lacked of positive effect of inulin (Biggs et al. 2007; Rehman et al. 2007). Furthermore, considerable attention has been paid recently to their potential physiological effects. Studies in experimental animals suggest that dietary inulin like other soluble fibres may modulate the concentration of serum lipids (Yamashita et al. 1984; Fiordaliso et al. 1995; Beylot 2005). Only few studies have been conducted to investigate the effect of inulin on hypolipidemic profile of broilers and results are not conclusive. In addition, most studies dealing with inulin are conducted in broilers fed diets based on corn as a main energy source, but unstable world corn market prices and low quality of imported corn make sometimes using locally grown wheat more economical.

Early works suggest that the composition of intestinal microbiota of the chicken is influenced by the food it eats. Apajalahati et al. (2004) showed that wheat-, corn- and rye-based diets each had their own characteristic effect on the intestinal microbial community. In addition, studies show that feeding of whole wheat (WW) instead of ground wheat (GW) reduces costs and, in some cases, the positive effect on bird performance and gut health (Svihus et al. 2004a, 2004b; Ravindran et al. 2006).

Therefore, the objective of this study was to determine the effects of chicory root powder (CRP) and wheat form on growth performance, carcass characteristics and some blood parameters in broilers chicken fed wheat-based diets.

2. Material and methods

2.1. Birds and diets

A total of 240 one-day old (Ross 308) broiler chickens used in a completely randomized design (with 4 __ 2 factorial arrangement), allocated to 8 treatments with 3 replicate and 10 birds per pen. Treatments were a combination of four levels of CRP (0, 1.5, 3, 4.5 g/kg of diet) and two forms of wheat grain (whole vs. ground). Each of the groups had 3 replicate with 10 chicks per pen. Treatments were a combination of four levels of CRP and two forms of wheat. The experimental diets were local wheat variety (sardari) and soya bean meal, formulated without added antibiotics and enzymes. Diets were fed from 1 d to 42 d including starter (1–21 d) and grower (21–42 d). Nutritional levels of the diets (Table 1) were based on NRC (1994) recommendations. All birds were given ad libitum access to feed and water, and were raised in an environmentally controlled room with 23 h light and 1 h dark programme. Temperature was maintained at 32°C from 0 d to 5 d, and then gradually reduced to 22°C according to normal management practices.

Table 1. Composition of treatment diets fed from 1 d to 21 d of age (starter) and from 21 d to 42 d of age (grower).

	Starter diets (1–21 d)				Grower diets (21–42 d)
	0% CRP	1.5% CRP	3% CRP	4.5% CRP	0% CRP	1.5% CRP	3% CRP	4.5% CRP
Ingredient
Wheat %	58.6	57.5	56.4	55.3	60.6	59.9	58.9	57.3
Soya bean meal %	32	31.5	31.2	31	29.9	29.2	28.6	29
Sunflower oil%	4.3	4.6	4.5	4.7	4.6	4.5	4.6	4.7
CRP %	0	1.5	3	4.5	0	1.5	3	4.5
DCP %	2.8	2.6	2.6	2.2	2.66	2.66	2.6	2.2
Limestone %	0.86	0.86	0.86	0.86	0.8	0.8	0.86	0.86
Methionine %	0.38	0.38	0.38	0.38	0.38	0.38	0.38	0.38
Lysine %	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22
Mineral %	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.25
Vitamins %	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.25
Salt %	0.34	0.34	0.34	0.34	0.34	0.34	0.34	0.34
Analysed composition
ME (kcal/kg)	2.92	2.92	2.9	2.89	2.96	2.96	2.97	2.97
CP %	20.16	20.1	20.1	20.04	19.3	19.2	19.25	19.1
Lysine %	1.24	1.22	1.22	1.21	1.18	1.16	1.16	1.14
Methionine	0.67	0.67	0.67	0.66	0.66	0.66	0.66	0.65
Methionine + Cysteine %	1.04	1.03	1.03	1.03	1.02	1.02	1.02	1.01
Calcium %	1.05	1	1	0.92	0.99	0.99	0.95	0.95
Available phosphorus %	0.53	0.51	0.51	0.46	0.51	0.51	0.47	0.45
Na %	0.16	0.16	0.16	0.16	0.16	0.16	0.16	0.16

Supplied the following per kilogram of diet: Vitamin A 9000 IU; Vitamin D₃ 2000 IU; Vitamin E 18 IU; Vitamin K 2 mg; riboflavin 6.6 mg; pantothenic acid 10 mg; pyridoxine 3 mg; folic acid 1 mg; Vitamin B₁₂ 15 μg; niacin 30 mg; choline 500 mg; Se 0.2 mg; I 1 mg; Cu 10 mg; Fe 50 mg; Zn 100 mg, and Mn 100 mg.

CRP, Chicory Root Powder; DCP, Dicalcium Phosphate; ME, Metabolisable Energy; CP, Crud Protein.

2.2. Chicken performance and blood parameters

At the end of 42 days, six birds were randomly selected from each treatment (two birds per pen); after an overnight fast and weighting, chickens were slaughtered by cervical dislocation. The body weight gain (BWG) and feed intake (FI) per pen were recorded each week. Feed conversion ratio (FCR) was calculated by totalling the amount of feed consumed divided by the BWG of the birds. Blood samples were collected from jugular vein of six birds of each treatment at 42 d of age. Blood samples were allowed to clot at 4°C for 2 h and were then centrifuged, and serum was separated and stored at −20°C for triglyceride (TG), total cholesterol, low-density lipoprotein (LDL)– cholesterol, high-density lipoprotein (HDL)– cholesterol and very low-density lipoprotein (VLDL)– cholesterol analyses.

2.3. Statistical analysis

Statistical analysis was carried out using the GLM procedure of SAS Statistical Analysis Software (2002) using a two-way factorial experiment. Tukey’s multiple range test was used to separate the means when differences between treatment means were significant (p < 0.05).

3. Results and discussion

3.1. Growth performance

Birds were in good health during the whole experiment. Mortality was lower than 1.25%. The body weight and cumulative feed-to-gain ratio of birds fed diets without or with 1.5%, 3% or 4.5% CRP on wheat-based diets are summarised in Table 2. Neither CRP inclusion levels nor wheat form affected FI, BWG and FCR of birds from 1 d to 21 d of age. In the present experiment, the effects of CRP and wheat form on performance were not consistent in both the growing (0–21 d) and finishing period (21–42 d). The inclusion of 4.5% CRP had a negative effect on BWG indicating that the effects of CRP inclusion may change with age and the development of the bird’s intestinal microbiota.

Table 2. Effects of CRP inclusion on the growth performance of broilers fed on WW- or GW-based diets.

Period	1–21 d			21–42 d			1–42 d
Parameters	BWG (g/bird)	FI (g/bird)	FCR	BWG (g/bird)	FI (g/bird)	FCR	BWG (g/bird)	FI (g/bird)	FCR
0% CRP	624	901	1.44	1930^a	3330^ab	1.69^ab	256^a	4230^ab	1.65
1.5% CRP	642	943	1.46	1950^a	3430^a	1.72^ab	2590^a	4370^a	1.68
3% CRP	602	850	1.4	1890^a	3150^b	1.66^b	2490^ab	4000^b	1.6
4.5%CRP	640	915	1.42	1700^b	3120^b	1.82^a	2340^b	4030^b	1.71
WW	610	895	1.46	1820^b	3220	1.72	2430^b	4110	1.68
GW	640	910	1.4	1910^a	3290	1.71	2560^a	4200	1.63
WW + 0% CRP	595	881	1.47	1879	3274	1.68	2474	4155	1.68
GW + 0% CRP	653	921	1.4	1995	3397	1.69	2648	4318	1.63
WW + 1.5% CRP	650	949	1.45	1899	3398	1.72	2550	4347	1.7
GW + 1.5% CRP	634	937	1.47	2006	3469	1.72	2647	4406	1.66
WW + 3% CRP	580	851	1.46	1900	3234	1.69	2480	4086	1.64
GW + 3% CRP	625	848	1.35	1889	3078	1.62	2514	3926	1.55
WW + 4.5% CRP	614	898	1.45	1624	2989	1.83	2237	3888	1.73
GW + 4.5% CRP	666	933	1.39	1783	3250	1.81	2449	4183	1.7
Total SEM	10	16	0.016	29	42	0.02	30	50	0.19
CRP%	NS	NS	NS	0.001	0.008	0.026	0.001	0.014	NS
Wheat form	NS	NS	NS	0.028	NS	NS	0.004	NS	NS
CRP% × wheat form	NS	NS	NS	NS	NS	NS	NS	NS	NS

Means with different letters in the same column differ significantly (p < 0.05).

NS, Non Significant; SEM, Standard Error of the Mean.

With regard to other studies in the literature, results of this study are consistent in some instances and inconsistent in other. The lack of response in BWG and FCR of broilers fed CRP up to 4.5% of diet agrees with results of Waldroup et al. (1993), Biggs et al. (2007) and Rehman et al. (2007, 2008) but fails to support the positive results of Ammerman et al. (1988a, 1988b), Yusrizal and Chen (2003), Xu et al. (2003) and Rebolé et al. (2010). The first broiler study by Ammerman et al. (1989) evaluated the effect of feeding inulin-type fructans on broilers growth performance and noted that 3.75 g/kg FOS produced heavier birds at 47 d of age. Yusrizal and Chen (2003) reported that supplementation of oligofructose and inulin improved BWG, carcass weight and feed conversion efficiency in female but not in male birds. Also Xu et al. (2003) reported that birds given 2 g/kg or 4 g/kg of FOS at the expense of corn in basal diet based on corn–soya bean meal improved average daily gain and feed-to-gain ratio. Recently, Rebolé et al. (2010) concluded that supplementation of inulin (10 g/kg and 20 g/kg) to a wheat- and barley-based diet improved BWG but not feed conversion efficiency in broilers. In the present study, feeding broilers with CRP up to 4.5% of diet did not affect BWG and FCR of broilers fed on WW- or GW-based diets. The differences in performance responses of broilers to dietary inulin-type fructans may be attributed to several factors, like type of products and their inclusion levels, composition of the basal diet and experimental hygiene conditions (Boguslawska et al. 2012). The lack of significant influence of the CRP on final BWG and FCR at 42 days in the present study could be attributed to the composition of the basal diet and for the environmental conditions of experimentation. Our trial was performed at the ideal conditions of experimentation.

There were no significant main effects of CRP inclusion on relative weights of internal organs and carcass traits (Table 3). Similar results were also reported by Waldroup et al. (1993). However, the studies performed by Yusrizal and Chen (2003) showed that adding chicory inulin and FOS at 10 g/kg diet improved carcass percentage and lowering the abdominal fat content in birds. Feeding WW compared to GW resulted in a significant increase in the relative weight of the gizzard, with and without digesta contents, as a percentage of the live weight of the bird. The increased grinding activity of a more developed gizzard (p < 0.05) resulting from WW feeding did not work additively with CRP supplementation (Table 3).

Table 3. Effects of CRP inclusion on the relative weight of organs and different section of the intestine of broilers fed on WW- or GW-based diets.

Treatments	Dressing percentage (%)	Spleen (%)	Abdominal fat (%)	Pancreas (%)	Liver (%)	Full gizzard (%)	Empty gizzard (%)
0% CRP	71	0.108	1.27	0.248	2.35^ab	2.41	1.77
1.5% CRP	71.1	0.102	1.45	0.241	2.21^b	2.6	1.92
3% CRP	70.4	0.107	1.51	0.277	2.45^a	2.74	1.96
4.5% CRP	70.9	0.107	1.52	0.247	2.29^ab	2.8	2.06
WW	69.2^b	0.109	1.46	0.257	2.34	2.95^a	2.16^a
GW	72.4^a	0.105	1.44	0.248	2.29	2.37^b	1.73^b
WW + 0% CRP	69.7	0.102	1.33	0.240	2.42	2.68	1.96
GW + 0% CRP	72.3	0.115	1.21	0.257	2.27	2.14	1.58
WW + 1.5% CRP	68.7	0.102	1.32	0.230	2.21	2.8	2.15
GW + 1.5% CRP	73.5	0.102	1.57	0.251	2.2	2.4	1.69
WW + 3% CRP	68.5	0.110	1.45	0.316	2.54	3.16	2.21
GW + 3% CRP	72.3	0.103	1.57	0.237	2.36	2.33	1.72
WW + 4.5% CRP	70.1	0.122	1.73	0.243	2.22	3.18	2.32
GW + 4.5% CRP	71.4	0.100	1.41	0.249	2.33	2.61	1.93
Total SEM	0.56	0.002	0.05	0.009	0.032	0.097	0.06
CRP%	NS	NS	NS	NS	0.0348	NS	NS
Wheat form	0.009	NS	NS	NS	NS	0.002	0.0009
CRP% × wheat form	NS	NS	NS	NS	NS	NS	NS

Means with different letters in the same column differ significantly (p < 0.05).

In the present study, WW feeding had no effect on the relative weight and length of the intestine compared to those birds given GW diets (Table 4). These results are consistent with other reports (Taylor and Jones 2001; Banfield et al. 2002) and may be due to the fact that birds had well-developed gizzards and were able to process the WW efficiently, removing the need for any further physiological adaptation relating to nutrient digestion or absorption (Banfield et al. 2002; Aghazadeh and TahaYazdi 2012).

Table 4. Effects of CRP inclusion on the relative length of different sections of gastrointestinal tract of broilers fed on WW- or GW-based diets.

	Relative length (cm/kg body weight)				Relative weight (%)
Treatments	Duodenum	Jejunum	Ileum	Small intestin^1	intestinal
0% CRP	1.26	5.63	0.74	7.64	5.15
1.5% CRP	1.24	5.51	0.72	7.48	4.92
3% CRP	1.39	5.83	0.79	8.02	5.27
4.5% CRP	1.37	6.18	0.78	8.34	5.19
WW	1.28	5.96	0.78	8.03	5.37
GW	1.34	5.62	0.73	7.71	4.9
WW + 0% CRP	1.17	5.78	0.76	7.72	5.67
GW + 0% CRP	1.35	5.48	0.72	7.55	4.63
WW + 1.5% CRP	1.23	5.50	0.70	7.44	4.89
GW + 1.5% CRP	1.24	5.52	0.74	7.52	4.95
WW + 3% CRP	1.41	6.18	0.83	8.43	5.68
GW + 3% CRP	1.37	5.48	0.75	7.61	4.87
WW + 4.5% CRP	1.32	6.37	0.84	8.54	5.24
GW + 4.5% CRP	1.41	6.00	0.72	8.14	5.17
Total SEM	0.027	0.1	0.019	0.131	0.159
CRP%	NS	NS	NS	NS	NS
Wheat form	NS	NS	NS	NS	NS
CRP% × wheat form	NS	NS	NS	NS	NS

Means with different letters in the same column differ significantly (p < 0.05).

¹ Small intestine = Duodenum + Jejunum + Ileum.

3.2. Blood parameters

Atherosclerosis is a leading cause of death in industrialised societies. Therefore, a reduction in risk factors for atherosclerosis, such as elevated concentration of plasma cholesterol and plasma LDL–cholesterol (Beylot 2005) and raised concentration of plasma TGs, is a major goal in public health. In the present study, TG and VLDL levels decreased (p < 0.05) when 4.5% CRP diet was fed compared with those of control, but reduction in GW diets was higher than those in WW diets as indicated by significant (p < 0.05) interaction between CRP and wheat form (Table 5). Similar results of lipid lowering effect of dietary oligosaccharides and specifically a decrease in the plasma TG concentrations in rats have been reported (Fiordaliso et al. 1995; Kim and Shin 1998).

Table 5. Effects of CRP inclusion on the blood parameters of broilers fed on WW- or GW-based diets.

Treatments	Cholesterol (mg/dl)	TG (mg/dl)	VLDL (mg/dl)	LDL (mg/dl)	HDL (mg/dl)
0% CRP	220.83	23.66^a	4.73^a	63.09	141.02
1.5% CRP	230.33	22.33^ab	4.46^ab	65.8	148.34
3% CRP	217	23.16^ab	4.5^ab	61.99	138.14
4.5% CRP	206.33	19.33^b	3.86^b	58.95	132.4
WW	249.41^a	24.66^a	4.93^a	71.25^a	161.03^a
GW	187.83^b	19.99^b	3.99^b	53.66^b	118.91^b
WW + 0% CRP	259.33	28.33^a	5.66^a	74.09	166.65
GW + 0% CRP	182.33	19^b	3.8^b	52.09	115.39
WW + 1.5% CRP	254.33	26^a	5.2^a	72.66	164.01
GW + 1.5% CRP	206.33	18.66^b	3.73^b	58.95	132.6
WW + 3% CRP	237.33	22.66^ab	4.53^ab	67.8	153.21
GW + 3% CRP	196.66	25.33^a	5.06^a	56.19	123.07
WW + 4.5% CRP	246.66	21.66^ab	4.33^ab	70.47	160.27
GW + 4.5% CRP	166	17^b	3.4^b	47.43	104.52
Total SEM	8.16	0.888	0.178	2.33	5.61
CRP%	NS	0.0199	0.0199	NS	NS
Wheat form	<.0001	0.0003	0.0003	<.0001	<.0001
CRP% × Wheat form	NS	0.004	0.004	NS	NS

Means with different letters in the same column differ significantly (p < 0.05).

HDL, high-density lipoprotein; LDL, low-density lipoprotein; VLDL, very low-density lipoprotein; TG, Triglyceride.

Studies in experimental animal and limited data from poultry suggest that, like other soluble dietary fibres, dietary inulin may act to depress total cholesterol and LDL–cholesterol (Fiordaliso et al. 1995; Yusrizal and Chen 2003). Yusrizal and Chen (2003) reported that the addition of inulin or FOS at a level of 10 g/kg of diet at 42 d of age significantly reduced serum cholesterol concentration in both male and female broilers. In contrast, a recent report by Velasco et al. (2010) found no influence of 5 g/kg or 10 g/kg of inulin on serum cholesterol or LDL–cholesterol concentration in broilers fed diet containing two different source of fat. In the present study, cholesterol and LDL–cholesterol concentrations tended to numerically decrease in a dose-dependent manner by addition of higher level of CRP. However, both TG and VLDL levels decreased (by 18.3% and 18.4%, respectively) when 4.5% CRP diet was fed, but reduction in GW diets was higher than those in WW diets as indicated by significant (p < 0.05) interaction between CRP and wheat form (Table 5). Similar resulted were reported by Velasco et al. (2010) who found that adding the inulin in broiler diet supplemented with different fat source reduced TG and VLDL concentration without affecting total blood cholesterol, HDL and LDL in broilers fed up to 34 d of age.

It was demonstrated that the hypotriacylglycorolemic effect of oligofructose is due to a reduced hepatic de novo fatty acid and triacylglycerol synthesis through inhibition of lipogenic enzymes (Kok et al. 1996). This hypothesis is further supported by a reduction in plasma VLDL particles, indicating a decreased production and secretion of VLDL (Fiordaliso et al. 1995). In this study, plasma TG and VLDL were significantly lower in CRP, especially in GW-based diets, which may support of this hypothesis.

4. Conclusion

The results of this study indicated that feeding CRP in GW-based diets does not adversely affect growth performance but stimulates hypolipidemic effects on broilers as reflected in lower TG with a lesser extent total cholesterol concentration.