Citation of this paper

Effects of Spring onion supplement on growth performance and blood chemistry of Ayam Cemani chickens raised for meat

Pham Tan Nha and Le Thu Thuy

Cantho University, Cantho City, Vietnam
ptnha@ctu.edu.vn

Abstract

A study was carried out to assess how adding spring onion supplement impacts the growth of Ayam Cemani chickens aged between 6 and 13 weeks. The study followed a completely randomized design, comprised 5 treatments representing varying levels of spring onion supplement, each replicated 4 times with 10 chickens per replication. The treatments involved different percentages of spring onion supplement (0, 0.5, 1.0, 1.5, and 2.0% dry matter) to be mixed into the diets, labeled as SP0, SP0.5, SP1.0, SP1.5, and SP2.0 respectively.

The study revealed significant improvements (p<0.05) in daily weight gain (DWG) for birds fed diets supplemented with spring onion (SP1.5 and SP2.0 treatments) compared to those on the unsupplemented control diet (SP0). Furthermore, feed conversion ratio (FCR) exhibited favorable reductions in the SP1.5 and SP2.0 groups, indicating improved feed efficiency. Additionally, spring onion supplementation positively impacted carcass characteristics, with significant increases (p<0.05) observed in breast and thigh meat weights. The findings suggest that dietary inclusion of spring onion at levels between 1.5 and 2% (dry matter) during the growth phase can enhance growth performance in Ayam Cemani chickens. Moreover, the study provides evidence for a potential cholesterol-lowering effect of spring onion supplementation, as evidenced by reduced triglyceride and total cholesterol levels in the chickens' blood.

Key words: spring onion, Ayam Cemani chickens, triglyceride, cholesterol

Introduction

In addition to some commonly raised chicken breeds such as: Tau Vang Chicken, Noi Chicken, Tre Chicken, Ac Chicken, successfully raised, there is also a new chicken breed introduced into our country, the Indonesian black chicken (Ayam Cemani). This chicken breed is known as a symbol of luck for Indonesian people. A unique feature of this chicken breed is that their bodies are completely black, from feathers, wings, legs, even skin. Indonesian black chicken (Ayam Cemani) is also classified as a rare poultry, so the price is quite high and farmers also have high income when raising this breed of chicken.

Onion leaves contain essential oils with the main ingredients being allicin, glucose, fructose, sucrose, maltose, galactose mannose, zylos and inorganic substances Ca, P, Fe; vitamins B1, B2, C (9.7 mg%), pectin and proto pectin. Green onions also contain 23.6 mg of quercetin per kg of fresh onions (Xu et al., 2005).

Onion stems also contain many essential oils with the main ingredients being allicin and diallydisulfite compounds, stearic, palmitic arachidic, oleic, and linoleic fatty acids. Mucilage polysaccharide, fructose-oligosaccharide, 2% cellulose, 3% hemicellulose, 41% protopectin, 24% protein.

For the digestive system, green onions have the effect of increasing the excretion of digestive juices (Nguyen Hieu Hoc, 2019), promoting the metabolism of proteins, lipids and carbohydrates to help improve appetite and fight diseases. Flatulence and indigestion. The volatile component of onions is the active ingredient allicin, which inhibits bacteria such as Bacillus diphtheria, B. tuberculosis, Salmonella dysenteriae, Staphylococcus aureus, Streptococcus hemolyticus. According to (Bui Thi Le Minh et al., 2017), adding 1% green onions (DM) to chicken diets reduces the number of E. coli and Salmonella spp in feces.

The aim of this research is to identify the most effective level of green onion supplementation in chicken diets to enhance the growth performance and blood chemistry of Ayam Cemani chickens reared in the Mekong Delta region of Vietnam, providing valuable recommendations to producers based on the findings.

Materials and methods

Location and climate of the study area

The experiment was conducted on a private farm in Vinh Long province, Vietnam, during the dry season (January - May 2023). Housing for the study was an open barn, resulting in ambient temperature and humidity fluctuating in accordance with external conditions. Average temperatures during the experiment ranged from 26 to 33°C, and humidity varied between 45 and 75%. Consistent with the dry season timing, rainfall was minimal. Chemical analyses of the experimental diets were performed at the laboratory of the Faculty of Animal Sciences, School of Agriculture, Can Tho University.

Experimental animals

One-day-old Ayam Cemani chickens were procured from a breeding farm in Long An province, Vietnam. From days 2 to 28 post-hatch, the chicks were exclusively fed a commercially prepared, concentrated pellet containing 20% crude protein. During days 29 to 35, this base diet was supplemented with a small, gradually increasing amount of the experimental diets being tested. At 36 days of age, all chickens received vaccinations against H5N1, Newcastle disease, and other prevalent poultry diseases prior to their inclusion in the formal trial.

Experimental design and treatments

Employing a completely randomized design, the study utilized 200 Ayam Cemani chickens, six weeks old with an average weight of 351 ± 9.5 g per bird. Random allocation ensured impartiality and control for potential biases. Five distinct treatment groups were established, each consisting of four replicate units housing ten birds with balanced sex distribution. The treatments implemented varying levels of spring onion supplementation in the chickens' diets: 0%, 0.5%, 1.0%, 1.5%, and 2% dry matter, denoted as SP0, SP0.5, SP1.0, SP1.5, and SP2.0, respectively. The trial spanned eight weeks, encompassing the chicks' age range from six to thirteen weeks. A detailed breakdown of the feed ingredients utilized in the diets is provided in Table 1.

Table 1. Feed ingredient composition of concentrate diet in the experiment
Feed	(%)	Feed	(%)

Rice bran	5.1	Premix vitamin	0.40
Maize	34.8	Premix mineral	0.50
Fish meal	10.1	CaCO₃	0.49
Broken rice	36.3	DCP	0.51
Soybean extraction	11.8

Feeds and preparation of spring onion

Spring onions preparation involves washing the onions thoroughly and then cutting them into small pieces approximately 1-1.5 cm in length. Afterward, weigh the spring onions and blend them into the chicken diet as per the predetermined ratio. It's important to note that all feed ingredients were procured simultaneously from the feed store throughout the experiment. The basal diet was specifically formulated to include 12.9 MJ metabolizable energy/kg dry matter and 18% crude protein. Prior to feeding, ensure thorough mixing of the spring onions with the feed. The chemical compositions of spring onions, feed ingredients, and the basal diet are detailed in Tables 2 and 3.

Table 2. Chemical compositions of 100 grams of fresh green onions
Item	Unit	Amount

Energy	Kcal	32
DM	Grams	10.87
CP	Grams	1.83
Carbonhydrate	Grams	7.34
EE	Grams	0.19
Ash	Grams	2.6
Sugar	Grams	2.33
Fat axit	Grams	133
Thiamine (B1)	Mg	0.055
Riboflavin (B2)	Mg	0.08
Niacin (B3)	Mg	0.525
Pantothenic acid (B5)	Mg	0.596
Vitamin B6	Mg	1.235
Folate (B9)	µg	3
Vitamin C	Mg	31.2
Canxi	Mg	181
Fe	Mg	1.7
Magnesium	Mg	25
Manganese	Mg	1.672
Phosphorus	Mg	153
Potassium	Mg	401
Sodium	Mg	17
Kẽm	Mg	1.16
Selen	µg	14.2
Nguyen Hieu Hoc anh Pham Tan Nha, 2019

Table 3. Chemical compositions of feed ingredients and basal diet (% DM)
Feed Item	Maize	Broken rice	Rice bran	Soybean Extraction	Fish meal	Basal diet

DM	88.6	86.7	86.0	89.5	91.9	89.1
OM	98.6	99.5	89.6	94.8	78.1	92.7
CP	8.08	9.29	12.5	43.4	60.4	18.1
EE	4.85	0.82	18.1	1.22	12.7	4.00
CF	2.12	0.59	6.59	5.44	0.19	3.60
NDF	28.5	7.35	32.1	12.3	11.0	17.0
Ash	1.40	0.51	10.4	6.82	21.9	7.30
ME (MJ/kgDM)	13.9	13.5	13.0	10.3	12.6	12.9
DM: dry matter, OM: orgarnic matter, CP: crude protein, EE: ether extraction, CF: crude fibre, NDF: neutral detergent fibre, ME: metablolizable ernergy (Janssen et al, 1989)

Housing and management

The experimental Ayam Cemani chickens were housed in custom-built enclosures crafted from a combination of wood and metal sheets. Each pen provided 2.5 m² of floor space for every 10 birds, ensuring adequate comfort and movement. Walls were constructed using a combination of wood and plastic netting for ventilation and light access. To provide bedding and encourage natural foraging behavior, the pens were floored with 20 cm of sand and rice straw. Feeders and waterers were strategically placed in front of each pen and meticulously cleaned every morning to maintain hygiene. Chicken litter was removed and replaced weekly to ensure a clean and healthy environment. The birds were fed a balanced diet three times daily: 7:00 AM, 1:00 PM, and 5:00 PM. The feed quantity was adjusted weekly based on actual intake, gradually increasing from 5% to 10% of body weight to meet their nutritional requirements. Additionally, the birds had unrestricted access to clean, fresh water throughout the experiment. Thinly sliced green onions were incorporated into the feed according to the predetermined experimental ratios (0%, 0.5%, 1.0%, 1.5%, and 2.0%) to investigate their potential effects on the study outcomes.

Measurements

Daily feed intake and nutrient consumption were meticulously monitored by collecting and weighing both offered feed and leftover portions (refusals) every morning. Additionally, weekly measurements were conducted to track individual chicken weight gain and calculate the feed conversion ratio, a metric reflecting feed efficiency.

Upon trial completion, four birds (two males and two females) from each experimental unit were humanely euthanized and subjected to a comprehensive carcass trait evaluation. This assessment adhered to the established protocols outlined by Salomon (1996) and encompassed various body measurements of the chickens. Furthermore, blood samples were collected at this time point for subsequent laboratory analysis of key biochemical parameters.

Chemical analyses

A thorough chemical analysis was conducted on the provided feed to ascertain its precise composition. This analysis encompassed measurements for dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), crude fiber (CF), and ash content. All analyses adhered to the established procedures outlined by AOAC (1990). Additionally, neutral detergent fiber (NDF) content was determined using the methodology described by Van Soest et al. (1991). Finally, metabolizable energy (ME) was calculated based on the method developed by Janssen (1989).

Statistical analysis

Statistical analysis of the collected data was conducted using the General Linear Model (GLM) implemented in Minitab program version 18.1.0 (Minitab, 2018). To identify statistically significant differences between treatment groups, a post-hoc analysis employing Tukey's Honestly Significant Difference (HSD) test, available within Minitab (2018), was performed.

Results and discussion

Daily intakes of feed and nutrients of growingAyam Cemanichicken

Table 4. Daily intakes of feed and nutrient of Ayam Cemani chicken (g/bird)
Item	Treatment					SE		p
Item	SP0	SP0.5	SP1.0	SP1.5	SP2.0	SE		p

DM	55.6^b	57.2^a	55.9^b	55.0^b	54.3^c		0.34	0.015
OM	51.6^b	53.0^a	51.8^b	51.0^bc	50.3^c		1.90	0.030
CP	10.1^ab	10.3^a	10.1^a^b	10.0^ab	9.80^b		0.05	0.022
EE	2.22^ab	2.29^a	2.23^ab	2.20^b	2.17^b		0.03	0.017
CF	2.00	2.06	2.01	1.98	1.95		0.02	-
NDF	9.46^ab	9.72^a	9.50^a^b	9.35^b	9.23^c		0.06	0.018
Ash	4.06^b	4.17^a	4.08^b	4.02^c	3.96^d		0.04	0.017
ME (MJ/bird/day)	0.72^b	0.74^a	0.72^b	0.71^c	0.70^c		0.02	0.024
^a,b,c Mean values with different superscripts within the same row are different at p<0 05

Daily consumption of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), and neutral detergent fiber (NDF) exhibited significant reductions (p<0.05) in birds fed the SP2.0 diet compared to other dietary groups. Conversely, the group receiving the SP0.5 diet demonstrated the highest intake levels for these nutrients. Interestingly, these findings diverge from those reported by Nguyen Hieu Hoc (2019) in a prior study with Tau Vang chickens. Hoc's study observed lower DM and CP intake levels, ranging from 45.9 to 49.4 g/day and 9.17 to 9.59 g/day, respectively. Furthermore, metabolizable energy (ME) intake was significantly higher (p<0.05) in birds from the SP0, SP0.5, and SP1.0 treatments compared to those in the SP1.5 and SP2.0 groups, likely attributed to their higher DM consumption.

Effects of dietary differentspring onion supplement on the growth performance of growingAyam Cemanichicken

Table 5. Daily weight gain, final live weight and feed conversion ratio (FCR) of Ayam Cemani chicken (g/bird)
Item	Treatment						SE	p
Item	SP0	SP0.5	SP1.0	SP1.5		SP2.0	SE	p

Initial live weight	350	348	352		353	350	7.5	-
Final live weight	1220^d	1250^c	1275^b		1310^a	1315^a	4.07	0.002
Daily weight gain	15.5^c	16.1^b^c	16.5^b		17.1^a	17.2^a	0.22	0.005
FCR	3.58^a	3.55^a	3.39^b		3.22^c	3.15^c	0.5	0.003
CP/ weight gain (g/kg)	648.0^a	642.6^ab	613.6^b		582.8^c	570.2^d	6.11	0.002
^{a. b. c} Mean values with different superscripts within the same row are different at p<0 05

Table 5 illustrates that daily weight gain (DWG) was notably higher for birds supplemented with spring onion (SP1.5 and SP2.0 treatments) compared to those without supplementation (SP0 treatment). These findings align with a study by Okali Usur (2020), which reported improved weight gain in goats supplemented with 3% garlic powder in their diet. The achieved DWG ranged from 15.5 to 17.1 g per chicken, consistent with values of 15.3 to 16.8 g per chicken observed in previous trials with Tau Vang chickens (Nguyen Hieu Hoc, 2019; Nguyen Van Nhan, 2019).

Figure 1. The effect of Spring onion on DWG

Chickens supplemented with spring onion exhibited notably higher final live weights compared to those in the SP0 treatment (p<0.05), which can be attributed to their higher daily weight gain. These final live weights were consistent with the range of 1220 to 1315g observed in a previous study involving Tau Vang chickens (Nguyen Van Nhan, 2019). Additionally, the findings revealed a significantly lower consumption of crude protein (CP) per unit of weight gain among chickens in the SP1.5 and SP2.0 treatments (p<0.05).

Figure 2. The effect of Spring onion on FCR

FCR of Ayam Cemani chickens was notably improved in the SP1.5 and SP2.0 treatments (p<0.05), likely attributed to the higher daily weight gain observed in those groups. The FCR results obtained in this study were comparatively lower, ranging from 3.24 to 3.53, in contrast to values reported by Pham Tan Nha (2019) in research on Noi chickens.

Effects of dietary differentspring onion supplement on carcass quality of growingAyam Cemanichicken

Table 6. Caracass values and internal organs of Ayam Cemani chicken supplemented spring onion in diet (g/bird)
Item	Treatment					SE	p
Item	SP0	SP0.5	SP1.0	SP1.5	SP2.0	SE	p

Slaughter live weight	1220^d	1250^c	1275^b	1310^a	1315^a	4.07	0.002
Carcass weight	866^d	894^c	922^b	950^a	955^a	31.0	0.031
% Carcass	71.0	71.5	72.3	72.5	72.6	1.97	-
Breast meat weight	172.4^d	179.6^c	185.3^b	204.2^a	206.2^a	8.60	0.002
% Breast meat	19.9	20.1	20.1	21.5	21.6	0.70	-
Thigh meat weight	129.1^d	135.0^c	142.9^b	154.8^a	157.5^a	3.16	0.048
%Thigh meat	14.9	15.1	15.5	16.3	16.5	0.42	-
Heart weight	8.6	9.2	9.80	10.1	9.98	0.67	-
Liver weight	21.3	21.7	22.5	23.1	23.2	4.01	-
Cecal length. cm	13.7	13.9	14.1	14.5	14.6	1.09	-
^{a .b. c} Mean values with different superscripts within the same row are different at p<0 05

Consistent with their final live weights, slaughter weights showed no significant differences between treatment groups. Notably, carcass weight exhibited a significant increase (p < 0.05) in birds fed diets supplemented with 1.5% and 2% spring onion (SP1.5 and SP2.0), as detailed in Table 6. However, the percentage of carcass yield remained comparable across treatments (p> 0.05), ranging from 69.1% to 72.4%, consistent with observations reported by Nguyen Hieu Hoc (2019). Both breast and thigh meat weights demonstrated significant increases (p< 0.05) in the SP1.5 and SP2.0 groups, while the ratio of breast to thigh meat remained unaffected by dietary treatment (p > 0.05). Additionally, no significant differences were observed in the weights of internal organs across treatment groups (p > 0.05).

Table 7. Blood biochemical indicators of Ayam Cemani chicken supplemented spring onion in diet (mmol/L)
Item	Treatment					Normal index of human
Item	SP0	SP0.5	SP1.0	SP1.5	SP2.0	Normal index of human

Quantification of Triglycerid	1.88	1.31	1.25	1.11	0.74	0.46 - 1.88
Quantification of total cholesterol	4.87	4.41	4.11	3.16	2.89	3.9 - 5.2
HDL-C (High density lipoprotein Cholesterol)	2.59	2.80	2.21	3.39	3.12	> 0.9
LDL-C (Low density lipoprotein Cholesterol)	1.36	0.87	1.70	1.58	0.823	< 3.4
Quantification of Albumin (g/L)	16.66	15.1	14.0	13.6	13.12	34 - 48
Center Lab Vietnam of Cantho city

Elevated Triglyceride levels pose significant health risks, disrupting the blood transport process and potentially leading to various adverse health outcomes. Prolonged accumulation of fat in blood vessel walls can lead to the narrowing of coronary arteries, thereby increasing the risk of heart attacks and strokes. Individuals with elevated Triglyceride levels are susceptible to conditions such as atherosclerosis, high blood pressure, obesity, and hyperlipidemia.

However, incorporating spring onion into the diets has been observed to reduce the Triglyceride index in the blood of local chickens, which can positively impact their health. Consequently, consumers who consume chicken meat with reduced Triglyceride levels may experience health benefits. Notably, the Triglyceride index was lowest in the SP1.5 and SP2.0 treatments, at 1.11 and 0.74 mmol/L, respectively.

Figure 3. The effect of spring onion on quantification of triglycerid

Analysis of total cholesterol concentrations revealed a decreasing trend from the SP0 to SP2.0 treatment groups. The highest value was observed in the SP0 group (4.87 mmol/L), while the lowest was recorded in the SP2.0 group (2.89 mmol/L). This finding suggests a potential cholesterol-lowering effect associated with increasing dietary spring onion levels.

Furthermore, similar patterns of decline were observed for HDL-C, LDL-C, and albumin quantification across the treatment groups. The SP2.0 treatment again exhibited the lowest concentrations, with values of 13.12 mmol/L, 13.6 mmol/L, 14.0 mmol/L, and 15.1 mmol/L for HDL-C, LDL-C, and quantification of albumin, respectively, alongside an albumin concentration of 16.66 g/L.

Figure 4. The effect of spring onion on quantification of total cholesterol

Cholesterol is a vital component for the body's functions, but excessive levels can lead to the accumulation of unused cholesterol in blood vessels, forming plaques that can narrow and block arteries, increasing the risk of cardiovascular diseases and strokes. The total cholesterol test index serves as an indicator of cardiovascular disease risk, with higher values indicating a greater risk.

The addition of spring onion to the diet resulted in decreased total cholesterol levels in the blood of local chickens, benefiting both chicken health and potentially human health when consuming chicken meat.

Conclusions

The supplementing the diets of growing Ayam Cemani chickens with spring onion at levels of 1.5 to 2.0% (dry matter) improved growth performance. Additionally, spring onion supplementation led to a decrease in triglyceride and total cholesterol levels in chicken blood.

Acknowledgments

I would like to express my gratitude to the Faculty of Animal Husbandry, School of Agriculture, Can Tho University, for providing me with the opportunity to conduct this experiment.

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