Growth performance and quality characteristics of flaxseed-fed broiler chicks

Abstract

A 42-day study was conducted to evaluate the effect of ground full-fat flaxseed supplementation on growth performance, carcass characteristics, α-linolenic acid (ALA), linoleic acid (LA) and organoleptic characteristics of broiler meat. A total of 200 one-day-old broiler chicks were randomly allocated to five experimental groups and were fed isoenergetic and isonitrogenous diets containing flaxseed at 0%, 2.5%, 5.0%, 7.5% and 10%. Flaxseed supplementation did not affect the weekly body weight of broiler chicks during the first three weeks, but thereafter it reduced significantly with increasing levels of flaxseed in the diets. Birds fed on 10% flaxseed showed a reduction of 10.08% in body weight as compared to the control group. Diets containing 5.0–7.5% flaxseed resulted in significantly lower weight gain, higher feed conversion ratio, energy efficiency ratio and lower protein efficiency ratio as compared to control and 2.5% flaxseed diets. The carcass characteristics data indicated a little variation in the evisceration rate and giblet among treatment groups, but the breast yield was significantly higher in control than flaxseed groups. The protein, fat and ash content of broiler meat were not affected with the level of flaxseed in the diets. However, the inclusion of flaxseed in the diets significantly increased the ALA in the breast and thigh tissues with no difference in the organoleptic quality of meat.

Keywords:

• flaxseed
• broiler
• growth performance
• α-linolenic acid

1. Introduction

Flaxseed is emerging as an important oilseed because of the presence of high α-linolenic acid (ALA, 18:3n-3) (Cunnane et al. 1993; Singh et al. 2011). It contains 35–45% oil of which 45–52% is ALA (Bhatty 1995). The beneficial effects of omega-3 fatty acids on human health are well established (Conners 2000; Simopoulos 2003). The ALA reduces the risk of cardiovascular disease (CVD), osteoporosis, rheumatoid arthritis and cancer (Prasad et al. 1998; Clark et al. 2000; Spence et al. 2003; Aldercreutz 2007). There is, thus, an increasing interest in enriching the omega-3 fatty acid content of meat. The US Food and Drug Administration (2004) gave qualified health claim status to n-3 polyunsaturated fatty acids (PUFA). It was stated that ‘supportive but not conclusive research shows that consumption of EPA and DHA may reduce the risk of coronary heart disease’. Omega-3 PUFA-enriched poultry meat has the potential to help meat consumers increase their n-3 PUFA intake. A minimum level of 300 mg of n-3 PUFA per 100 g of meat is needed to label the product as n-3 PUFA-enriched (Canadian Food Inspection Agency 2003).

Flaxseed and its meal have traditionally been used in equine, bovine and laying hen diets. The products, such as eggs and beef, from animals fed flax had a higher content of omega-3 fatty acids (Scheideler et al. 1994; Maddock et al. 2003). This has led to renewed interest in flax production and feeding flax to livestock. The fatty acid profile of the meat and fat is directly affected by the source of fat in the poultry diet. Therefore, it is possible to change the fatty acid profile, especially the ratio of omega-3 fatty acids, by feeding flax oil or flaxseed, in poultry products which can offer an alternative to enhance omega-3 daily intake in consumers’ diet (Leskanich and Noble 1997; Mridula et al. 2012a; Mridula et al. 2012b). Ajuyah et al. (1991) reported less carcass fat, larger leg weights and increased omega-3 fatty acids in meat in flax-fed chickens at an inclusion rate of 10–20%. In a companion study, Ajuyah et al. (1993) determined higher levels of ALA in dark meat than white meat in broilers fed with 15% flax. The literature showed that more than 10–15% dietary inclusion of flaxseed may decrease broiler growth (Ajuyah et al. 1993); hence the inclusion level of flaxseed in the present study was limited to a 10% level. Keeping in view the findings of previous studies, the present study was carried out to compare the effects of ground levels of flaxseed supplementation on growth performance, proximate composition, ALA content and sensory characteristics of meat in broiler chicks.

2. Materials and methods

2.1. Study subjects

Day-old sexed commercial (Vencob) broiler chicks (n = 200) were randomly allocated to five groups with 20 chicks in each and equal sex ratio and were placed in the individual floor pens. The chicks were vaccinated according to the standard procedure. The corn-soybean meal-based diets (Table 1) supplemented with 0%, 2.5%, 5.0%, 7.5% and 10% flaxseed were each randomly offered to two groups of chicks. The diets were formulated according to Bureau of Indian Standard (BIS) (1992) using various ingredients procured from the local market. The feed samples were analysed for crude protein (CP) content (AOAC 2000). The chicks were fed starter (2900 kcal ME/kg, 22% CP), grower (2900 kcal ME/kg, 20% CP) and finisher (3000 kcal ME/kg, 18% CP) diets during 0–14, 15–28 and 29–42 days of age, respectively. Feed and fresh water were made available ad libitum at all times. The chicks were reared under standard conditions of housing and management in floor pens with paddy husk as litter material.

Table 1. Composition of starter, grower and finisher diet.

	Flaxseed (%)
	Phase I					Phase II					Phase III
Basal ingredients (%)	0	2.5	5.0	7.5	10.0	0	2.5	5.0	7.5	10.0	0	2.5	5.0	7.5	10.0
Maize	51.5	50.6	48	46	43.4	55.75	55	52.5	50	47.25	60	60	60	60	58
Rice polish (de-oiled)	5	5	5	5	5	5	5	5	5	5	3.5	0	0	0	0
Flaxseed	0	2.5	5	7.5	10	0	2.5	5	7.5	10	0	2.5	5	7.5	10
Soybean meal	39.5	38.4	37.7	36.8	36.2	34	33	32.25	31.5	31	29	29	27.75	26.5	25.7
Vegetable oil	0.5	0	0	0	0	0.5	0	0	0	0	2.05	1.8	1	0.2	0
Wheat straw	0.3	0.3	1.1	1.5	2.2	1.55	1.3	2.05	2.8	3.55	2.25	3.5	3.05	2.6	3.1
DCP	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5
Limestone powder	1.2	1.2	1.2	1.2	1.2	1.2	1.2	1.2	1.2	1.2	1.2	1.2	1.2	1.2	1.2
Salt	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5
M + C (additional)	0.223	0.219	0.219	0.218	0.213	0.212	0.209	0.207	0.204	0.199	0.199	0.193	0.193	0.192	0.190
Lysine (additional)	0.07	0.081	0.085	0.093	0.094	0.103	0.112	0.117	0.122	0.121	0.131	0.128	0.141	0.155	0.16
Calculated composition
Protein, %	22.06	22.04	22.04	22.01	22.06	20.06	20.09	20.08	20.07	20.14	18.06	18.10	18.08	18.07	18.08
ME, kcal/kg	2915.4	2916.1	2911.4	2921.1	2919.2	2907.5	2915.8	2913.1	2910.4	2906.1	3003.5	3005.3	3007.6	3009.9	3006.3
Crude fat, %	2.13	3.04	3.89	4.77	5.62	2.24	3.16	4.02	4.87	5.72	2.34	3.25	4.19	5.13	6.01
Lysine, %	1.13	1.12	1.11	1.11	1.10	0.997	0.99	0.98	0.73	0.98	0.87	0.87	0.86	0.85	0.84
M+C, %	0.68	0.68	0.68	0.68	0.69	0.61	0.61	0.61	0.62	0.62	0.54	0.55	0.55	0.54	0.55
Calcium, %	1.05	1.06	1.06	1.07	1.07	1.04	1.05	1.05	1.06	1.06	1.03	1.03	1.04	1.05	1.05
Available phosphorous, %	0.47	0.47	0.48	0.48	0.48	0.46	0.46	0.47	0.47	0.47	0.44	0.44	0.45	0.45	0.45

Note: Additives included (per 100 kg): Liver tonic (Superlive^TM), 0.25 g; Vitamin C, 20 g; Choline chloride, 50 g; Trace minerals, 50 g; Vitamin A, 825000IU; Vitamin D₃, 165000IU; Vitamin E, 500 mg; Vitamin B_12, 0.015 mg; Vitamin K, 100 mg; Thiamine, 80 mg; Riboflavin, 6 mg; Vitamin B₆, 160 mg; Niacin, 1200 mg; Biotin, 0.2 mg; Folic acid, 1.0 mg; Ferrous sulphate, 120 mg; Cupric sulphate, 12 mg; Potassium iodide, 1 mg; Manganese sulphate, 90 mg; Zinc sulphate, 60 mg; Salinomycin, 500 mg. In addition to these supplements, methionine and cystine (M + C) were also added to fulfil the requirements (BIS 1992).

2.2. Growth performance

Weekly live weight and feed intake per pen were recorded. The cumulated weight gain, feed conversion ratio (FCR), energy efficiency ratio [EER; ME intake (kcal)/weight gain (g)] and protein efficiency ratio [PER; weight gain (g)/protein intake (g)] data were calculated for the entire experimental period. Mortality, if any, was recorded daily.

2.3. Biochemical evaluation, carcass yield and organoleptic characteristics

At the end of six weeks of the experiment, four birds (two male and two female) were randomly selected from each treatment and were sacrificed to compare the carcass characteristics using the standard procedure (Ricard & Rouvier 1967). Moisture, protein, fat and ash content of breast and thigh meat samples were determined following the standard procedures (AOAC 2000). Fatty acids namely ALA and linoleic acid (LA) content in breast and thigh muscles were determined by gas liquid chromatograph (NUCON GC 5765, made in India). ALA and LA content in the samples were identified by matching the retention times with those of their corresponding standards (Palmquist & Jenkins 2003). Breast meat samples of equal dimension from each treatment were used for sensory evaluation (Keeton 1983).

2.4. Statistical analysis

All the data were subjected to one-way analysis of variance (Snedecor & Cochran 1980) with flaxseed as the main effect. Comparison among means was made by a multiple range test (Duncan 1995) at a 5% level of significance.

3. Results and discussion

3.1. Growth performance

The weekly body weight of chicks (Figure 1) indicated no significant difference among various treatment groups during the first three weeks of the experiment. However, a progressive decline in body weight with an increase in the level of flaxseed supplementation was recorded starting with the fourth to sixth week of the experiment. At the end of the sixth week, significantly higher body weight in the control group was recorded. The body weight with 2.5% flaxseed level was significantly more than all other levels tested. There was no significant difference in body weight of chicks fed 5.0% and 7.5% levels. However, at the 10% level, the chicks had significantly lower body weight than all other groups. A similar trend was observed in the body weight of the birds up to six weeks of age, fed with 5–10% of flaxseed (Arshami et al. 2010). Pekel et al. (2009) reported lower body weight of birds fed with flaxseed diets with copper supplementation. Ajuyah et al. (1991) and Lee et al. (1991) also reported that the broilers fed diets containing 15% flaxseed had 4.9–6.7% lower body weight than birds fed 10% canola seed. Ajuyah et al. (1993) reported a decline of 17% in body weight of birds fed with 15% flaxseed in the diet as compared to corn-soybean diet. In the present study, 10% body weight reduction was observed at 10.08% flaxseed level in the diet.

Figure 1. Effect of flaxseed (FS) on weekly body weight in broiler chicks.

The performance data for different age divisions (Table 2) indicated that during 0–14 days there was no significant difference in weight gain among the control and treated groups. The feed intake, FCR and EER were insignificant but higher, and the PER was lower in all the treated groups compared to the control group. During 15–28 days of growth, body weight gain in chicks was significantly reduced with increasing levels of flaxseed in the diet, but the feed intake was similar in all the groups. FCR and EER were significantly higher and the PER was lower in all the treated groups compared to the control group except in chicks fed with 2.5% flaxseed in the diet during this period.

Table 2. Effect of flaxseed supplementation on growth performance of broiler chicks.

	Level of flaxseed in the diet (%)
Parameters	0	2.5	5.0	7.5	10
Weight gain (g)
Phase I	329.80 ± 5.80	325.40 ± 4.81	333.90 ± 4.10	320.10 ± 3.39	319.65 ± 2.90
Phase II	682.10 ± 0.57^a	667.00 ± 0.85^b	654.10 ± 0.14^c	658.60 ± 2.97^bc	628.70 ± 7.35^d
Phase III	667.93 ± 2.72^a	653.45 ± 17.89^a	574.00 ± 10.18^b	574.15 ± 3.61^b	557.55 ± 12.80^b
Overall weight gain	1679.83 ± 9.09^a	1645.85 ± 12.23^b	1562.00 ± 5.94^c	1552.85 ± 9.97^c	1505.90 ± 8.34^d
Feed consumption (g)
Phase I	459.67 ± 6.29	460.94 ± 1.64	458.80 ± 2.69	459.65 ± 1.48	455.56 ± 4.24
Phase II	1192.23 ± 4.72	1193.00 ± 9.90	1197.75 ± 9.55	1193.90 ± 10.75	1195.25 ± 8.13
Phase III	1637.95 ± 17.18	1638.88 ± 9.92	1636.50 ± 7.50	1637.60 ± 6.08	1634.00 ± 2.26
Overall feed consumption	3289.84 ± 28.18	3292.81 ± 1.66	3293.05 ± 14.35	3291.15 ± 6.15	3284.81 ± 10.11
Feed conversion ratio (FCR)
Phase I	1.39 ± 0.044	1.42 ± 0.026	1.37 ± 0.025	1.44 ± 0.011	1.43 ± 0.0
Phase II	1.75 ± 0.008^c	1.79 ± 0.013^bc	1.83 ± 0.014^b	1.81 ± 0.008^b	1.90 ± 0.035^a
Phase III	2.45 ± 0.036^b	2.51 ± 0.054^b	2.85 ± 0.064^a	2.85 ± 0.029^a	2.93 ± 0.071^a
Overall FCR	1.96 ± 0.027^c	2.00 ± 0.014^c	2.11 ± 0.017^b	2.12 ± 0.010^b	2.18 ± 0.005^a
Protein efficiency ratio (PER)
Phase I	3.25 ± 0.102	3.20 ± 0.059	3.30 ± 0.060	3.16 ± 0.023	3.18 ± 0.001
Phase II	2.85 ± 0.014^a	2.78 ± 0.020^ab	2.72 ± 0.021^b	2.75 ± 0.012^b	2.61 ± 0.048^c
Phase III	2.26 ± 0.033^a	2.20 ± 0.047^a	1.94 ± 0.043^b	1.94 ± 0.019^b	1.89 ± 0.046^b
Overall PER	2.64 ± 0.037^a	2.58 ± 0.018^b	2.45 ± 0.020^c	2.44 ± 0.010^c	2.37 ± 0.005^d
Energy efficiency ratio (EER)
Phase I	4.06 ± 0.13	4.13 ± 0.08	4.00 ± 0.07	4.19 ± 0.03	4.16 ± 0.00
Phase II	5.08 ± 0.02^c	5.22 ± 0.04^bc	5.33 ± 0.04^b	5.28 ± 0.02^b	5.53 ± 0.10^a
Phase III	7.37 ± 0.11^b	7.54 ± 0.16^b	8.58 ± 0.19^a	8.59 ± 0.09^a	8.81 ± 0.21^a
Overall EER	5.79 ± 0.08^c	5.92 ± 0.04^c	6.24 ± 0.05^b	6.28 ± 0.03^b	6.45 ± 0.02^a

Note: Values in each cell are mean ± SD; values bearing different superscripts in a row differ significantly (P < 0.05); Phase I (1–2 weeks), Phase II (3–4 weeks), Phase III (5–6 weeks).

During the finishing phase of growth, birds in the control group and 2.5% flaxseed group achieved significantly higher weight gain compared to other treatment groups. FCR, EER and PER were also significantly better in these groups. During the entire experiment, the control group significantly gained highest body weight with lowest feed consumption. Poor FCR, EER and PER data indicated the decreased efficiency of feed, protein and energy utilization by birds with increasing level of flaxseed in the diet. Rahimi et al. (2011) also reported the better performance of birds in terms of weight gain and FCR with the control diets than those fed with flaxseed (7.5–15%). Roth-Maier et al. (1998) also reported that as low as 5% of flaxseed in either ground or whole form reduced the body weight and FCR. Bond et al. (1997) concluded that flaxseed was not a practical oil source, as more than 10% of flaxseed in the diet caused a significant performance reduction. Shen et al. (2005) also observed lower weight gain and poor feed conversion efficiency in the birds fed with flaxseed supplemented diet as compared to canola or extruded full-fat soybean-based diets. Moreover, poor performance of birds fed with flaxseed-based diets may also be due to the presence of anti-nutritional factor such as linatine. Klosterman et al. (1967) also reported that linatine in mucilage can decrease the productivity of the animal by decreasing the amount of endogenous enzymes released from the pancreas, resulting in reduced digestion of feed particles. Also the non-starch polysaccharides in mucilage of flaxseed increase intestinal viscosity in monogastric animals and decrease nutrient availability (Classen & Bedford 1991). These could be responsible for lower FCR, PER and EER leading to a decrease in body weight gain.

3.2. Carcass yield and quality

The carcass characteristics data (Table 3) indicated not much of a difference in the evisceration rate and giblet among treatment groups. The breast yield was highest in the control group followed closely with a non-significant difference in 2.5% flaxseed group. However, the difference among all the treated groups was not significant. Although a slight variation was observed in drumstick and thigh per cent of the carcass weight of different treatment groups, it was statistically non-significant. In contrast to this study, Arshami et al. (2010) reported non-significant results for breast weight per cent between treatment (flaxseed 5–10%) and control group with the trend of 5% > 10% > 7.5% > 0.0% flaxseed in the diet. Pekel et al. (2009) also observed no effect of flaxseed supplementation on carcass weight, yield and breast weight in broiler chickens.

Table 3. Effect of flaxseed supplementation on carcass characteristics and organoleptic properties of meat of broiler chicks.

	Level of flaxseed in the diet (%)
Parameters	0	2.5	5.0	7.5	10
Carcass characteristics
Eviscerated, %	62.76 ± 0.91^a	61.55 ± 0.21^b	62.22 ± 0.43^ab	61.51 ± 0.10^b	61.70 ± 0.30^b
Giblet, %	4.23 ± 0.23	4.51 ± 0.25	4.25 ± 0.11	4.42 ± 0.21	4.19 ± 0.11
Breast, %	30.03 ± 1.10^a	28.93 ± 1.56^ab	28.23 ± 0.97^b	28.26 ± 0.67^b	28.15 ± 0.69^b
Drumstick, %	14.42 ± 1.17	15.25 ± 1.04	15.71 ± 0.56	15.22 ± 0.15	15.49 ± 0.53
Thigh, %	15.05 ± 1.05	16.70 ± 2.03	16.80 ± 0.81	16.33 ± 0.49	16.46 ± 1.03
Edible, %	66.99 ± 0.75^a	66.07 ± 0.37^b	66.48 ± 0.50^ab	65.93 ± 0.16^b	65.89 ± 0.38^b
Inedible, %	33.01 ± 0.75^b	33.93 ± 0.37^a	33.52 ± 0.50^ab	34.07 ± 0.16^a	34.11 ± 0.38^a
Nutritional composition
Breast muscle
Moisture, %	73.54 ± 1.73	73.60 ± 3.11	73.47 ± 1.31	73.50 ± 1.73	73.65 ± 0.92
Protein, %	20.29 ± 1.60	20.17 ± 1.02	20.32 ± 1.70	20.16 ± 1.02	20.21 ± 0.81
Fat, %	2.49 ± 0.13	2.55 ± 0.21	2.54 ± 0.10	2.41 ± 0.11	2.46 ± 0.10
Ash, %	1.25 ± 0.17	1.21 ± 0.18	1.27 ± 0.13	1.24 ± 0.20	1.24 ± 0.14
ALA, mg%	54.15 ± 12.42^d	82.01 ± 9.41^d	168.79 ± 13.38^c	246.90 ± 21.27^b	334.10 ± 20.45^a
ALA, % fatty acid	2.18 ± 0.49^d	3.21 ± 1.29^d	6.63 ± 1.32^c	10.22 ± 0.88^b	13.56 ± 0.83^a
LA, mg%	1042.38 ± 23.11^a	1075.79 ± 34.88^a	965.0 ± 27.72^b	860.80 ± 36.86^c	857.66 ± 56.55^c
LA, % fatty acid	42.07 ± 1.03^a	42.20 ± 1.36^a	37.92 ± 1.08^b	35.66 ± 1.52^bc	34.82 ± 2.29^c
Thigh muscle
Moisture, %	71.69 ± 1.88	71.73 ± 1.09	71.72 ± 1.05	71.69 ± 1.77	71.72 ± 1.48
Protein, %	19.12 ± 0.87	19.10 ± 0.77	19.08 ± 0.79	19.15 ± 1.17	19.14 ± 1.13
Fat, %	5.78 ± 1.04	5.81 ± 0.72	5.68 ± 0.51	5.79 ± 0.58	5.75 ± 1.05
Ash, %	1.230.04	1.20 ± 0.20	1.26 ± 0.27	1.23 ± 0.17	1.20 ± 0.14
ALA, mg%	125.81 ± 18.85^d	174.88 ± 46.46^d	348.94 ± 13.94^c	582.08 ± 66.75^b	783.15 ± 48.02^a
ALA, % fatty acid	2.18 ± 0.35^d	3.01 ± 0.80^d	6.14 ± 0.25^c	10.05 ± 1.15^b	13.62 ± 0.84^a
LA, mg%	2360.55 ± 81.56^a	2350.53 ± 88.19^a	2170.51 ± 86.27^b	2068.57 ± 76.45^b	2051.79 ± 69.0^b
LA, % fatty acid	40.84 ± 1.41^a	40.46 ± 1.51^ab	38.21 ± 1.52^bc	35.73 ± 1.32^c	35.68 ± 1.20^c
Organoleptic characteristics
Appearance and colour	7.94 ± 0.73	7.44 ± 1.13	7.56 ± 0.73	7.67 ± 0.71	7.72 ± 0.44
Tenderness	7.67 ± 0.71	6.92 ± 0.92	7.11 ± 1.34	7.64 ± 0.72	8.06 ± 0.73
Juiciness	7.19 ± 1.19	6.78 ± 0.83	7.19 ± 1.07	7.61 ± 0.78	7.69 ± 0.93
Flavour	7.67 ± 0.56	7.33 ± 0.75	7.33 ± 0.75	7.33 ± 0.75	7.33 ± 0.97
Overall acceptability	7.62 ± 0.53	7.12 ± 0.75	7.30 ± 0.86	7.56 ± 0.57	7.70 ± 0.57

Note: Values in each cell are mean ± SD; values bearing different superscripts in a row differ significantly (P < 0.05).

Meat sample analysis showed a lower protein and higher fat content in the thigh meat samples as compared to breast meat (Table 3), as also reported by Taylor et al. (2005), in broilers fed on corn-soy diet. However, different levels of flaxseed in the diet did not affect the protein, fat and ash content of breast and thigh meat samples. Roth-Maier et al. (1998) had also found that 5% or 7.5% flaxseed, as ground or whole seed, did not affect the total lipid content in thigh tissues. Olomu and Baracos (1991) demonstrated that up to 4.5% flaxseed oil did not alter the lipid content in either white or dark muscles. However, Ajuyah et al. (1990) reported that the addition of 10% or 20% of either flaxseed or flaxseed meal significantly decreased the lipid content in both white and dark meats. Results indicated that the increasing level of flaxseed in the diet significantly increased the ALA content in the meat samples except at the 2.5% inclusion level than the control. Different levels of flaxseed in the diet also reduced the LA in meat samples. Other studies had (Ajuyah et al. 1993; Shen et al. 2005; Betti et al. 2009; Rahimi et al. 2011) also reported that the response of tissue fatty acid profiles to dietary flaxseed inclusion follows a proportional pattern that reflects dosage and period of dietary flaxseed treatment.

Organoleptic properties of breast meat from all the treatment groups indicated no significant difference in the mean scores for colour and flavour (Table 3). Although statistically similar, mean sensory scores for tenderness and juiciness for the 10% flaxseed group were slightly better than the control group. The overall acceptability scores for breast meat from all the treatments ranged from 7.12 in control to 7.70 in 10% flaxseed-fed groups, but the differences were statistically non-significant. Statistically similar mean overall acceptability scores for all the treatment groups showed that flaxseed supplementation did not affect the organoleptic quality of meat as also observed in other studies too (Mridula et al. 2011).

4. Conclusions

This study revealed that the supplementation of flaxseed in the diet had adverse effects on growth performance of broiler chicks. However, the higher level of flaxseed increased the ALA content in the meat. It is, therefore, recommended that before supplementing flaxseed for its beneficial effects for the consumers, the performance loss may be weighed in terms of the premium price of the meat; the consumer is ready to pay for the product.

Acknowledgements

The authors wish to express their sincere thanks to Department of Science and Technology, New Delhi, India for providing financial assistance to carry out this work. The help and guidance rendered by Dr R. T. Patil, Director, CIPHET, Ludhiana, and Dr A. L. Saini, Professor and Head, Department of Livestock Production Management, COVS, GADVASU, Ludhiana, are thankfully acknowledged.