Growth performance, haematological and serum biochemical indices of broiler chicks served Aloe vera gel extract supplement

Edeh Henry Onyeji, Ani Augustine Ogbonna, Ogwuegbu Mercy Chisara, Ilo Stanley Uzochukwu, Onodugo Matthew Onyeka, Ude Fredrick Ugochukwu, Edeh Chinyere Gloria¹ and Ede Amos Ejike²

Department of Animal Science, University of Nigeria Nsukka, Nigeria
henry.edeh@unn.edu.ng
¹ Department of Plant Science and Biotechnology University of Nigeria Nsukka
² Department of Agricultural Education, Federal College of Education Eha-Amufu, Enugu State

Abstract

One hundred and twenty 14-day old broiler chicks were used in a study to investigate the growth response of boiler chicks to oral supplementation with Aloe vera gel extract (AVGE). The chicks were randomly divided into five groups of 24 birds each in a completely randomized design. Each treatment was replicated three times with 8 chicks per replicate. Birds on treatments T0, T0,4, T0,8 and T1,2 received ordinary water, 10, 20 and 30% aqueous AVGE supplements respectively. The chicks were fed on formulated broiler starter diet containing 2.80Mcal/kgME and 23.57% crude protein and given ad-libitum drinking water throughout the experiment. In the end of the study, the chicks were bled aseptically of 5 ml blood into EDTA and plain sample bottles via the cephalic veins for haematological and serum biochemistry analyses respectively in the haematology laboratory. The study lasted for a period of four weeks. Results showed that there were significant differences (p>0.05) in final body weight (FBW), average daily weight gain (ADWG), average daily feed intake (ADFI), feed conversion ratio (FCR), protein efficiency ratio (PER) and cost of feed per kg gain (CFG). T1.2 had a better FBW (1296g), ADWG (38.07), FCR (2.36. Significant (p<0.05) differences existed in all serum and haematological parameters examined except in white blood cells (WBC) counts. The results on serum and haematological parameters suggested that oral supplementation of Aloe vera gel enhanced the blood indices of the birds. It is evident from the results obtained in this study that T1.2 had a better feed conversion ratio (2.36). It is therefore recommended that oral administration of Aloe vera gel extract supplement to broiler chicks be included at 30% inclusion level (1.2litre of AVGE + 4 litre of water).

Keywords: blood indices, body weight, crude protein, feed intake, oral

Introduction

It is not surprising that Nigeria is highly deficient in animal protein security with the per capita consumption put at 9.3g/day as against the 35g/day recommended by the FAO to be the minimum requirement for the growth and development of the body (Esobhawan et al 2008). This calls for the production of fast growing animals with short generation interval like pigs, rabbits and poultry. Poultry in particular is one of the fastest means of achieving appreciable improvement in the nutritional standard of the populace because of its short generation interval, quick turnover rate and relatively low capital investment (Smith, 2001; Ani and Okeke, 2011). More recently, in response to public concern over dietary fat, poultry has become a popular substitute for beef and pork. In addition, poultry is also free from religious taboos, social, economic and some climatic constraints. Broilers therefore have great potentials for providing the protein needs of Nigerians due to their ability to convert grain and other by-products into meat (Oluyemi and Roberts, 2000). Broilers need vitamins and minerals for good health. Vitamins and minerals are known to work synergistically. Aloe vera contains numerous vitamins: Vitamin A, C, and D (are crucial antioxidants that combat free radicals in the body); Vitamin B and choline are concerned with the production of energy, amino acid metabolism udeveloping muscle mass. Vitamin B12 (folic acid) is responsible for the production of red blood cells (Jalal et al 2014).Oral administration of vitamins and minerals to birds is inevitable especially in the time of stress and outbreak of diseases. The use of Aloe vera extract in broiler production is a step in the right direction since it is a potential source of vitamins and minerals. Haematology refers to the study of the numbers and morphology of the cellular elements of the blood – the red cells (erythrocytes), white cells (leucocytes), and the platelets (thrombocytes) and the use of these results in the diagnosis and monitoring of disease (Merck Manual, 2012). Haemtological studies are useful in the diagnosis of many diseases as well as investigation of the extent of damage to blood (Togun et al 2007). Haematological parameters are good indicators of the physiological status of animals (Khan and Zafar, 2005). Blood act as a pathological reflector of the status of exposed animals to toxicant and other conditions (Olafedehan et al 2010). As reported by Isaac et al (2013) animals with good blood composition are likely to show good performance. Laboratory tests on the blood are vital tools that help detect any deviation from normal in the animal or human body (Ogunbajo et al 2009). This study was therefore conducted to evaluate the growth performance, serum biochemical and haematological indices of broiler chicks served Aloe vera gel extract supplement.

Materials and methods

The study was carried out at the Poultry Unit of the Department of Animal Science Teaching and Research Farm, University of Nigeria, Nsukka. Nsukka lies in the derived savanna region and is located on longitude 6⁰ 25N and latitude 7⁰ 24 E (Ofomata1975) and at an altitude of 430m above the sea level (Breinholt et al 1981). The climate of the study area is a typical humid tropical type, with a relative humidity range of 56.01 - 103.83%. Average diurnal minimum temperature ranged from 22⁰C - 24.7⁰C while the average maximum temperature ranges from 33⁰C - 37⁰C (Okonkwo and Akubuo, 2007). Annual rainfall ranges from 1567.05mm to 1846.98mm (Meteorological Center, Crop Science Department, University of Nigeria Nsukka, 2009 unpublished). The study lasted for a period of four weeks.

Preparation of Aloe vera gel extract

Fresh Aloe vera leaves were collected from Mbu town in Isi-uzo Local Government Area of Enugu State. The leaves were washed with clean water to remove dirt. Aloe vera gel was extracted manually from 1kg leaves by making a cut on the leaves with a pocket knife. The gel was scooped out with a small spoon and drained into a beaker. The extract was prepared by pouring 400ml (0.4litre) of fresh gel into a glass bottle containing 1.5 litre of clean tap water. The bottle was agitated for about 2 minutes to ensure thorough mixing, thereafter it was kept for 30minutes at room temperature prior to use. The homogenized gel extract was prepared at the interval of two (2) days and served to the animals fresh according to treatments.

Experimental birds and management

One hundred and twenty 14-day old broiler chicks were used for the study. The broiler chicks of both sexes were randomly allotted to five treatment groups of 24 birds each, in a completely randomized design (CRD). The treatments were as follows: T0 = ordinary water; T0,4 = (0.4litre of AVGE + 4litre of water); T0,8 = (0.8litre of AVGE+4 litre of water) and T1.2 = (1.2litre of AVGE + 4 litre of water). Treatment 0 served as the control. Each treatment was replicated three times with 8 chicks per replicate placed in a deep litter pen of fresh wood shavings measuring 1.50m x 1.50m. All the groups were fed the same formulated broiler starter diet containing 2.80Mcal/kgME and 23.57% crude protein (Table 1).

Routine management practices such as medication and vaccination were strictly observed. The experimental feed, AVGE, water and vitalyte were given ad libitum to the birds for the 4 weeks experimental period. Birds in each replicate were weighed at the beginning of the experiment and subsequently on weekly basis to determine the weight gain of birds. Feed intake was recorded daily and was determined by the weigh-back technique, and this involved obtaining the difference between quantity of feed offered and the left over the following morning. Feed conversion ratio (FCR) was calculated from the data on feed intake and weight gain as the number of grams of feed consumed per gram of weight gained over the same period. (FCR= feed intake/weight gain)

Haematological and serum biochemical evaluation of the experimental chicks

At the 4^th week of the experiment, three birds per treatment were randomly selected and blood samples were collected from the wing veins of each bird using sterilized syringe and emptied into sterilized bottles containing EDTA (Ethylene diaminetetracetic acid) for haematological analysis, and into the bottles without EDTA for serum biochemical analysis. Haematological parameters determined include haemoglobin concentration (HbC), packed cell volume (PCV), white blood cell (WBC) count, and red blood cell (RBC) count. The PCV was determined by the microhaematocrit method described by Schalm et al ( 1975), and Mitruka and Rawnsely (1977) using a microhaematocrit centrifuge and reader (Hawksley,1989). The Hb was determined using a haemoglobinometer (Marienfeld, Germany) Hawksley, 1989), while the WBC counts were carried out by the haemocytometer method using an improved Neubauer counting chamber (Hawksley, 1989) and avian RB`C and WBC diluting fluids as described by Campbell and Coles (1986) and Lamb (1991). Serum metabolites (total protein (TP), glucose albumin, globulin, creatine, cholesterol and calcium) were also determined according to the methods described by (Campbell and Coles 1986).

Proximate and statistical analyses

The Aloe vera gel extract was assayed for proximate composition by the method of AOAC (2005). Data collected were subjected to analysis of variance (ANOVA) for completely randomized design (CRD) using a statistical package for social sciences (SPSS 2015) version 17.0 software package model. Significantly different means were separated using Duncan’s New Multiple Range Test (Duncan, 1995).

Results and discussion

The crude protein value (20.02%) obtained in the present study is higher than the crude protein value of 6.86% reported by Muaz and Fatma (2013). However, the crude fibre and ash values (10.00% and 8.99%, respectively) obtained in the present study were lower than crude fibre and ash values (13.35%, and 16.88 %, respectively) reported by Muaz and Fatma (2013). The proximate values obtained in the present study were also higher than the values (moisture, 11.7%; ether extract, 2.91%; ash, 2.36%; crude protein, 4.73% and crude fibre, 7.84%) reported by Adesuyi et al (2012). The observed differences, especially in the crude protein and crude fibre contents may be due to differences in geographical locations, age and varieties/cultivars of the leaves evaluated in the different studies. It is well known fact that as leaves advance in age, the crude protein reduces whereas the crude fibre content increases (Mahima et al 2014)

Effect of aqueous Aloe vera gel extraction on performance of starter broiler birds

The effect of aqueous Aloe vera gel extract on growth performance of starter broiler birds is shown in Table 3. There were significant (p<0.05) differences among treatments in final body weight, average daily weight gain, feed conversion ratio, protein efficiency ratio and cost of feed per kg weight gain. Birds on T1.2 (1269g) had significantly (p<0.05) higher final body weight (FBW) than birds on other treatments. The final body weight of T0 was significantly (p>0.05) lower than other treatments. The control group (36.46g) had a lower average daily weight gain than other treatment while T1.2 (38.07g) showed significant (p<0.05) increase than other treatments. The AVGE had a better feed conversion ratio (FCR) on T1.2 (2.36) than other treatments while T0 had a poor FCR than the positive control and AVGE groups. The control group (1.55) was statistical similar (p>0.05) in protein efficiency ratio (PER) value with T0.4 and T0.8. T1.2 had a better PER than the control group.

Figure 1. Effect of aqueous Aloe vera gel extract on daily weight gain	Figure 2. Effect of aqueous Aloe vera gel extract on FCR

The final body weight of birds in 1.2 as compared to birds on other treatments. The observed increase in the FBW of birds served with 1.2 litre of AVGE + 4 litre of water may be attributed to some active ingredients in Aloe vera gel extract with diversified antimicrobial activities, and these might have enhanced the digestion of ingested feed, and perhaps might have assisted in the absorption of the digested nutrients. Similar findings have been reported by Meisam et al (2016). The present finding also corroborates with earlier report of (Ojha et al 2012) who found out that Aloe vera gel extract had a positive response in body weight gain of broiler birds. However, the results of the present study disagree with the report of Sinurat et al (2002) which showed that feeding broiler chicks with fresh Aloe vera gel (0.25 g/kg) and dry Aloe vera gel (0.25 - 1.0 g/kg) had no significant effect on body weight. The fact that birds on T1.2 had better feed conversion ratio than other treatment suggest the adequate inclusion level. In a similar report, Durrani et al (2006) had shown oral supplementation with aloe vera and turmeric resulted in enhanced feed intake and feed efficiency. The observed increase in protein efficiency ratio(PER) of birds on treatment 4 tends to suggest that at the 30% AVGE inclusion level, the vitamins, especially vitamin B and choline present in Aloe vera may have been involved in amino acid metabolism. These vitamins are known to play significant roles in amino acid metabolism (Jalal et al 2014).

Effect of aqueous Aloe vera gel extract on hematological indices of broiler starter birds

The effect of aqueous Aloe vera gel extract on hematological indices of starter broiler birds is presented in Table 4. There were significant (p<0.05) differences among treatments in all the haematological parameters evaluated with the exception of white blood cells (WBC). The value of packed cell volume (PCV) of T1.2 was significantly (p<0.05) higher than the packed cell volume (PCV) T0, but statistically similar (p>0.05) to the rest of other groups. T1.2 significantly (p>0.05) decreased in red blood cells (RBC) counts compared to T0 and T0.8 but was significantly similar (p>0.05) to T0.4. The haemoglobin concentration value showed that T0.4 was significantly (p<0.05) higher than the control but statistically similar (p>0.05) to, T0.8 and T1.2. and T0.4 had higher significant (p<0.05) values in mean cell volume than the control but was statistically similar (p>0.05) to T0.8. The heterophil values showed that T0.4 and T0.8 significantly (p<0.05) decreased compared to the control group but statistically similar to T1.2. The results also revealed that the control group (T0) decreased significantly (p>0.05) in lymphocyte values compared to T0.4 but had statistically (p>0.05) similar value with T0.8 and T1.2. Birds on treatments 3 was significantly (p<0.05) higher in monocyte value compared to birds on treatment 2 but was statistically similar with birds on control and other groups. Eosinophil value of T1.2 was statistically (p<0.05) higher than the control but statistically (p>0.05) similar to T0.8. Finally, T0.4 and T1.2 were significantly (p<0.05) higher than the control and other groups in basophil values.

The significant (p<0.05) differences that existed among treatments in all the haematological parameters evaluated with the exception of white blood cells (Table 4) agrees with the report of (Ojha et al 2012) which showed that oral administration of Aloe vera to birds significantly increased the RBC count and the Hb contents of the treated birds. The values obtained in this study were in the normal range of values by Jain, (1993) for PCV (22.0-35.0), Hb (7.00-13.0), RBC (2.5-3.5), and WBC (1.2-3.0). The results were also within normal range of Merck, (2012) of blood parameters for PCV (32%), Hb (12 g/dl), WBC (5.5 x 103μl), MCV (174 FI), MCH (61 Pg), MCHC (33 g/dl). The present findings did contradict Campbell, (2013) who recorded normal range of hematological parameters of PCV (35.9-41; 0%), Hb (11.60-13.68g/dl), RBC (4.21-4.84 X 106/ml, WBC (4.07-4.32 X 103/ml, MCV (81.60-89.10FI), MCH (27.20-28.90pg) and MCHC (32.41-33.37%) in broiler chickens. The reason may be due to the age of the birds as reported by Tufan and Ramazan (2011) that Hb amounts and PCV values increased with the advancement of age, being lowest in the chicks and highest in the adults except for RBCs and WBCs that reduced with advancement of age. The increase in the blood indices could be related to the chemical composition of the extract or gel. Aloe vera gel is known to contain vitamins A, C, and E, vitamin B (thiamine), niacin, vitamin B 2 (riboflavin), choline, folic acid, histidine, glycine, choline and other essential amino acids such as anthraquinones, saponins, phenolics, and polysaccharide (Jalal et al 2014). These vitamins and minerals play major roles in health status of every animal. As reported by Isaac et al (2013) animals with good blood composition are likely to show good performance.

Effect of aqueous Aloe vera gel extract on serum biochemical indices of broiler birds

Table 5 shows Effect of aqueous Aloe vera gel extract on serum biochemical indices of broiler birds. T0.4 was significantly (p > 0.05) decreased compared to T0 and T1.2 but were similar to T0.8 in total protein. The albumin value of T0.8 was significantly (p<0.05) decreased compared to other groups. In globulin analysis, T0.4 was significantly (p<0.05) decreased compared to T0, T0.8 and T1.2. The value of glucose decreased significantly (p<0.05) compared to other groups as the dietary inclusion of aloe vera gel increases. T1.2 had a high significant (p<0.05) value of creatine than other treatment groups. Finally, the calcium value of T1.2 showed a significant (p<0.05) increase compared to other groups.

Data on serum biochemical parameters (Table 5) showed that significant (p<0.05) differences existed among treatment groups. The serum glucose in this study was not with the normal reference values (197-299) given by Clinical Diagnostic Division (1990) for serum glucose.

The creatinine levels of this study fall within the normal range established by Merck (2012) which is between 0.1-0.4 mg/dl. Globulin values in this study are within the normal range for Gallus gallus specie that is 0.5 to 1.8 g/ dL as cited by Thrall (2007). The cholesterol value in this finding do not contract the normal range of 32.47±8.54 mg/dl to ≤ 130 mg/dl) as reported by Basmacioglu H and Ergul M (2005). This finding did not support Mehala and Moorthy (2008) who reported that no significant difference among the treatment groups by dietary inclusion of Aloe vera and curcuma longa and its combinations in broiler birds.

The findings of a significant increase in serum creatinine in treatment 1.2 (1.2litre of AVGE + 4 litre of water) was in agreement with, Biu et al (2010) and Rabo et al (2003) who reported significant increase in serum creatinine and urea levels.

Reduced protein level in T0.4 (0.4litre of AVGE + 4 litre of water) and albumin levels in T0.8 (0.8litre of AVGE + 4 litre of water) tallies with Mehala and Moorthy (2008). It was also observed in this finding that AVGE groups had lower glucose value compared to the control group T0 (water). This was in agreement with Rajasekaran et al (2006) who stated that the oral administration of Aloe vera gel extract (300mg/kg body weight per day) to streptozotocin induced diabetic rats had a significant reduction in fasting glucose. The decreasing effect of Aloe vera to glucose level may be the reason why some preliminary studies have also suggested that it may be a powerful antiviral agent, and potent immune system enhancer. It is being tested as a possible treatment for certain types of cancer and conditions as serious as diabetes (Jalal et al 2014).

Furthermore, the no significant difference observed in T0 and T0.4, T0.8 and T1.2 respectively in level of cholesterol supports Mehala and Moorthy (2008).

The significant increase observed in the calcium level in this report may be attributed to the calcium content of Aloe vera as reported by (Jalal et al 2014) that among the important minerals found in Aloe vera are: calcium, chromium, copper, iron, magnesium, manganese, potassium, phosphorous, sodium, and zinc. These minerals are essential for good health and are known to work in synergistic combinations with each other, with vitamins and other trace element (Jalal et al 2014).

Conclusion

• It is evident from the results obtained in this study that T1.2 had a better feed conversion ratio, average daily weight gain and cost of feed per kg gain. It is therefore recommended that oral administration of Aloe vera gel extract supplement to broiler chicks be included at 30% inclusion level (1.2litre of AVGE + 4 litre of water).

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