| Livestock Research for Rural Development 29 (1) 2017 | Guide for preparation of papers | LRRD Newsletter | Citation of this paper |
A study involving 144 Gold Line/Bovine Nera layers was conducted at Mpima, Kabwe District in the Central Province of Zambia to determine the effects of feeding Aloe vera and Propolis on egg production and egg size. The layers (36 weeks old) were randomly allotted in equal numbers to four treatments in a completely randomized design, which involved feeding commercial layers feed only (CONT), commercial layers feed + Aloe vera (ALOE); commercial layers feed + Propolis (PROP), and commercial layers feed + Aloe vera + Propolis (ALOEPROP). Both Propolis and Aloe vera were extracted and administered in liquid form at a rate of 2 ml/kg body weight on a daily basis for four weeks. Commercial feed was given at a rate of 0.1 kg per bird per day. The eggs were collected and counted twice a day and weighed. The egg production levels were computed as percentages over the four-week period. A One-way Analysis of Variance was applied to determine the effects of different treatments on egg production levels and egg weight, using Genstat.
Hen day egg production was higher (P=0.001) in ALOEPROP (90.8%) and ALOE (88.5%) layers than in PROP (81.5%) and CONT (78.1%) layers. However, there were no differences between treatments in egg size. It is concluded that Aloe vera and Propolis have a positive effect on egg production and possibly egg weight. A combination of the two additives showed significant positive effects on egg production. Further research to determine full benefits of a combination of the two natural additives in egg production is recommended.
Key words: layer productivity, natural additives, small scale producers
The poultry industry in Zambia provides formal employment to over 80,000 people, with 50,000 being permanent jobs and 30,000 being seasonal jobs (African Farming 2014). The performance of the industry between 2005 and 2010 was a strong 20% growth per year (Ncube et al 2016). Apart from providing employment, poultry production plays an important role in providing food as well as contribution to the national economy. According to African Farming (2014), Zambia's poultry sector contributes around 4.8 per cent to agricultural gross domestic product (GDP).
The United Nations Social and Economic Council (2011) recognized the key role played by small-scale farmers particularly women, while noting their challenges especially lack of access to knowledge, skills, inputs, credit, markets and infrastructure. In Zambia today, small scale farmers rearing commercial layers are faced with numerous challenges, with feed prices and disease having the greatest impact. Efficiency of feed utilization is one of the major concerns in commercial egg production as feed cost is the major factor of the total cost of production. Feed alone contributes between 70-80% of the total cost of production in egg type layers (Farooq et al 2003). Better utilization of feed is therefore the leading factor in minimizing the cost of production (Elwardany et al 1998). Farooq et al (2002), quoting Ascard et al (1995), noted that one layer requires 2.5 kg of feed to produce 1 kg of eggs. Thus, scientific ways must be explored to reduce the amount of feed required to produce 1 kg of eggs by one layer. This means finding solutions to increase both the number and the weight of eggs produced by a single layer so that small-scale farmers can increase productivity. In Zambia, egg size for most heavy laying birds ranges between 46-60 g (M. Ngosa Personal Communication). Increasing productivity as well as egg size in layers is critically important in the Zambian smallholder poultry industry as this is directly related to increased revenue.
Scientists in different countries have explored different products in an effort to increase poultry production. Two natural products, namely, Aloe vera and Propolis have been studied widely. Propolis is a mixture of beeswax (secreted from special glands on the abdomen of the bees) and resins collected by the honeybee from plants, particularly from flowers and leaf buds (Krell 1996). In the bee hive, it is used to reduce the size of the entrance and to patch up holes or cracks; it is also used as an antiseptic, lining each cell and the interior of the hive. Propolis has important pharmacological properties that can be used for a wide range of purposes including anti-inflammatory and anti-diabetes agent, immune system stimulant, antioxidant, antiviral and bacteriostatic and bactericidal agent, among many other uses (Bogdanov 2016). Aloe vera gel on the other hand contains wound healing, anti-parasitic, anti-viral, anti-fungal and anti-bacterial properties (Boudreau and Beland 2006). Antibiotic growth promoters have been helpful in improvement of growth performance and feed conversion ratio in poultry (Izat et al 1990; Dibner and Buttin 2002; Miles et al 2006). Many studies that have been done on herbs as alternatives to antibiotics have shown that they can modulate nutritional metabolism, immune responses, and intestinal health of food-producing animals, demonstrating good potential as substitutes for dietary antibiotics (Gong et al 2014). Antimicrobial properties of herb extracts have been demonstrated in some studies (Cowan 1999). In Zimbabwe Aloe vera and Aloe spicata have been used to determine the extent of the usage in the health management of chickens (Mwale et al 2005). Aloe vera has also been studied for its suitability as an alternative to antibiotic growth promoters (Darabighane et al 2011).
There is, however, a gap of information on the effects the two natural additives in egg production when fed together. Further, Aloe vera has been studied more on its medicinal attributes rather than as a feed additive for layers. In Zambia, Aloe vera and Propolis are readily available but none of these products has been scientifically tested to ascertain their effects in commercial layers both under commercial egg production and small-scale egg production. The objective of this study was therefore to evaluate the effects of feeding Aloe vera and Propolis, as single products and in combination, on the productivity of commercial layers under small scale production.
The study was conducted at Mpima Major Seminary Farm in Kabwe, Central Province 14◦26΄ S and 28◦27ʹ E. The farm is located about 140 km from Lusaka, the capital city of Zambia. The farm was chosen for this study because it had adequate facilities for this type of study and was also representative of small-scale farmers on one hand and commercial farmers on the other. Further, the farm offered a real practical situation where results could directly be interpreted for use by the farmers.
A total of 144 Gold Line/Bovine Nera commercial layers (36 weeks old) were used in the study, with four treatments in a completely randomized design. The treatments were demarcated with wire gauze. An equal number of birds (36 birds) were allotted to each of the treatments, with three replicates. The birds were reared on a deep litter system with maize bran as litter at a stocking density of 10 birds per m2 to allow free movement in the house. The birds were weighed on day 1 of the experiment and based on average weight, feed was given to allow each layer consume 0.1 kg per day. Feed and clean water were given twice per day, at 07:50 hrs and 14:00 hrs.
Commercial layers’ feed, bought from commercial companies, in combination with Aloe vera and Propolis formed the basis of experimental diets (Table 1). The control (CONT) birds were those that were fed on commercial layers’ feed only without any additive; the other treatments consisted of feeding commercial feed with Aloe vera in water (ALOE), commercial feed with Propolis in water (PROP), and commercial feed with a combination of Aloe vera and Propolis in water (ALOEPROP). The nutrient content of the commercial feed was as follows: Crude protein 16.51 %, Calcium 4.41 %, Phosphorus 0.47 %, Metabolizable energy 3502 cal/g.
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Table 1. Experimental Diets |
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Treatment |
Combination of commercial feed and additive |
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CONT |
Commercial feed only |
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ALOE |
Commercial feed + Aloe vera |
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PROP |
Commercial feed + Propolis |
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ALOEPROP |
Commercial feed + Aloe vera + Propolis |
Extraction of Propolis was done according to the method of Blonska et al (2004) with some modifications. Briefly, about 1 kg of Propolis was collected from bee hives at a farm in Kapiri Mposhi about 50 km north of Kabwe. The Propolis was cut into small pieces of about 4 cm3 and cleaned off the wax and debris. A 30% tincture was made by adding 700 ml of 96% ethanol to 300 g Propolis in a 2 litre plastic container and sealed tightly with a plastic lid (Photo 1). The container was wrapped in a black plastic and stored for 14 days in a dry dark room to prevent reaction with light. The container was shaken once daily to ensure a good extraction of the Propolis. The liquid was then filtered through a 2 mm kitchen sieve into another plastic container (Photo 2) which was left open to allow the extract to evaporate until a quarter of the content had escaped.
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| Photo 1. Appearance of the extract after extraction | Photo 2. Appearance of the extract after 14 days |
Aloe vera leaves (Photo 3) were harvested from Rivendell Farms, and using a knife, the latex of the Aloe vera leaf was removed to expose the clear gooey jelly like tissue. The tissue was then placed in a kitchen blender for grinding (Singh et al 2004). About 4,000 ml of gel was obtained from this process (Photo 4). The same amount of water was added to the gel (1:1 ratio), and the solution was put into an air tight container and refrigerated at 4 °C.
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| Photo 3. Aloe vera is a succulent plant species of the genus Aloe. It grows wild in tropical climates around the world and is cultivated for agricultural and medicinal uses. Source: Wikipedia |
Photo 4. Aloe vera gel following extraction from leaves |
Administration of ethnopropolis and Aloe vera was done through drinking water (Majida et al 2014; Singh et al 2014) based on body weight of the birds (de Castro and Higashi 1995; Newairy et al 2009). To this effect, a representative sample of birds were weighed and an average body weight computed. Based on this, the total weight of birds in each experimental treatment was calculated; 2 ml/kg body weight of ethnopropolis and 2 ml/kg body weight of Aloe vera were then added to the drinking water every morning. The additives were given in the morning to ensure total consumption by the end of the day.
The daily egg collections and egg weights from each treatment were recorded. The raw data were then inputted into Windows Excel (2010) for semi-processing. The number of eggs from each treatment were computed into percentages to find production capacity (hen day egg production) while the egg weights were averaged. The semi-processed data were exported into Genstat (13.1 version 2010) for statistical analysis. A One-way Analysis of variance (ANOVA) was done to determine the effects of different treatments on the parameters. Separation of means was done using Duncan’s Multiple Range test.
The hen day egg production in ALOEPROP (90.8±0.62%) and ALOE (88.5±1.24%) layers was higher (P=0.001) than in PROP (81.53±0.91%) and CONT (78.1±1.6%) layers (Figure 1).
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| Figure 1. Average hen day egg production from layers fed commercial feed only (CONT), commercial feed + Propolis (PROP), commercial feed + Aloe vera (ALOE), commercial feed + Aloe vera + Propolis (ALOEPROP). a, b P=0.001 |
There were no differences among the treatments with regard to egg size (Figure 2).
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| Figure 2. Average egg size (g) for layers fed commercial feed only (CONT), commercial feed + Propolis (PROP), commercial feed + Aloe vera (ALOE), commercial feed + Aloe vera + Propolis (ALOEPROP). P=0.73 |
Results of the present study in the ALOE layers are in agreement with other studies where Aloe vera has been studied and tested for its medicinal attributes but also as a natural feed additive, particularly in broiler diets and to a lesser extent in layers diets. In commercial layers, Moorthy et al (2009) who fed diets containing 0.1% Aloe vera powder and a combination of 0.1% Aloe vera powder and 0.1% Curcuma longa powder to White Leghorn birds found that Aloe vera fed as a single additive or in combination with Curcuma longa resulted in layers producing significantly more eggs which were also heavier compared to Control layers that were fed on commercial diet only. Similar results were also reported in Japanese quails where the total cumulative egg number and the hen day egg production including the albumin diameter were significantly higher in the quails that were fed with Aloe vera (100 ml/litre water) than those given the control diet (Hasan 2014).
Results of the present study are, however, not in agreement with those of Pasaribu et al (2006) who reported that Aloe vera barbadensis did not have any significant effect on all parameters including hen day production, egg weight, feed consumption, feed conversion ratio, and various egg quality attributes except for Haugh Unit (HU). While a clear explanation for this apparent difference may not be given, it is possible that the amount of Aloe vera given and the method of administration could be factors. Pasaribu et al (2006) administered a dry gel through feed (1 g/kg feed) whereas in the present study, the Aloe vera gel was mixed with drinking water following which 2 ml/kg body weight was given.
While Aloe vera has been studied more with regard to its medicinal attributes, such attributes could actually be associated with increased performance of egg production as observed in the present study as well as many other studies. The Aloe vera extract has been used as a therapy in village poultry in countries including Gambia, Zimbabwe and Tanzania (Kitalyi 1998). Mwale et al (2005) indicated that Aloe vera leaf and juice may be used in animals internally or externally for disease and parasite control. In a comprehensive review on ethnoveterinary research and development as a new direction in ethnobiology, McCorkle (1986) reported the use of Aloe vera in controlling coccidiosis. The Aloe extract concentration has an effect on sporulation of coccidian oocysts by killing or inhibiting growth and development of oocysts. A study in Western Kenya (Okitoi et al 2007) revealed that Aloe vera is used in treating New Castle disease in indigenous poultry. Results of the study also showed that extracts of Aloe spp. exhibited significant antimicrobial activities against bacteria such as Salmonella tymphi, Staphylococcus aureus and Escherichia Coli.
Lately, in a comprehensive review on the use of Aloe vera as a feed additive in broiler diets, Darabighane and Nahashon (2014) noted that Aloe vera was a well-known herb characterized by properties such as anti-bacterial, anti-viral, anti-fungal, anti-tumor, anti-inflammatory, immunomodulatory, wound-healing, anti-oxidant, and anti-diabetic effects. The authors further observed that during the past years, attention had in fact shifted toward Aloe vera as a natural additive to broiler diets, and studies had shown that Aloe vera could improve immune response and growth performance in broilers, apart from being an excellent alternative for antibiotic growth promoters and anticoccidial drugs.
As earlier indicated, the several studies (Boudreau and Beland 2006; Darabighane et al 2011; Gong et al 2014) on medicinal attributes of Aloe vera support the fact that such attributes could be associated with increased performance of commercial layers in the present study. This is because the birds fed with this natural additive were healthier and therefore able to convert more feed into actual production. Productivity with regard to hen day egg production and egg size was therefore higher.
In the present study, Propolis, used as a single additive did not significantly affect hen day egg production or egg size. However, numerical values of the measured parameters showed a trend where PROP layers showed higher performance of hen day egg production as well as egg size. It is possible that the short experimental period could have an effect on the significance of the effects of Propolis.
Other studies have demonstrated significant effects of Propolis. For example, Bonomi et al (1976), working with 4,000 four-and-half old Hubbard Golden hens, administered different levels of Propolis (10, 20, 30 mg/kg diet). The reported results showed that Propolis in the diet significantly increased egg production, egg weight, and feed utilization compared with the controls. Recent studies have also revealed positive results in layers fed with Propolis. A study done in 42-week old Leghorn layers that were reared under heat stress conditions and supplemented with Turkish Propolis at the level of 5 g/kg diet reported increased feed intake, improved feed conversion ratio, increased hen day egg production and increased egg weight in the supplemented laying hens (Seven 2008). Similarly, Galal et al (2008) in their study on productive performance and immune response of laying hens as affected by Propolis supplementation found that the hens fed the diet containing 100 and 150 mg Propolis produced significantly more eggs and heavier eggs compared to the control group. Feed intake was also higher and there was an improved feed conversion ratio in these birds compared to the control group. Eggshell quality was also improved in the hens fed Propolis.
Of late, Abdel-Kareem and El-Sheikh (2015), studying supplementation of Propolis using different rates in Lohmann LSL hybrid layers, found that the laying hens fed diets containing 250 and 1000 mg Propolis/kg diet significantly produced more and heavier eggs in comparison with the control group. In broilers, improved performance has also been reported. For example, Shalmany and Shivazad (2006) who studied the effects of supplementation of Propolis on Ross broiler chicks from day-old to 6 weeks reported that the average weight gain, feed consumption, and feed efficiency were all significantly higher for Propolis-fed birds compared to the control birds. Further, the mortality rate reduced in Propolis-fed birds compared to those on the control diet.
Bonomi et al (1976) in their work with the Hubbard Golden hens concluded that the improved effects resulting from Propolis were partially due to the presence of flavonoids as well as increased feed intake of Propolis-supplemented diets compared to the control diets. Ziaran et al (2005) who observed increased performance of broilers following administration of dietary oil extract Propolis suggested that flavonoids could act similar to anabolic agents with estrogenic effect and thereby induce effects that are similar to growth promoting hormones in animals. The authors further suggested that propolis could influence cholesterol synthesis. Furthermore, as in the case of Aloe vera, Propolis has also been found to exhibit positive effects on the health of birds as it possesses antibacterial activity. Different researchers (Trusheva et al 2006; Katircioglu and Mercan 2006; Yaghoubi et al 2007) have reported that Propolis antibacterial activity is attributed to a number of phenolic compounds, mainly flavonoids, phenolic acids and their esters. Flavonoids have been proven to account for many of the health giving benefits (Joseph and Raj 2010). Given these arguments, a healthy animal would naturally consume more feed and convert more energy into actual production.
To the best knowledge of the authors, this is the first study investigating the effects of a combination of the two natural additives, Aloe vera and Propolis, on the performance of commercial layers. As seen from the results, the treatment with the combination of the additives had the most positive effect on both egg production capacity (hen day egg production) and egg size, although there were no statistical differences between ALOEPROP and ALOE layers. It may be deduced from these results that the effects of Aloe vera and Propolis were complimentary, thereby resulting in a more enhanced performance of the layers. A more comprehensive study is, however, necessary to investigate the effects over a longer period as well as take a more comprehensive approach with regard to performance parameters including egg quality.
We are indebted to Fr. Paul Simukanzye and Sr. Grace Chambalakoko including other clergy and religious at Mpima Major Seminary Farm, who offered their facilities and experimental birds willingly, allowing us to conduct this research. Special thanks are due to Mr. John Enright who supplied Aloe vera from his Rivendell Farm and also facilitated the supply of Propolis. We thank Dr. M.T Daura, Mr. D. Zulu and Mr. M. Ngosa who made inputs by providing the necessary information in the course of the study.
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Received 29 August 2016; Accepted 9 November 2016; Published 1 January 2017