Effect of replacing essential amino acid and soybean seed with meat and bone meal on efficiency of feed utilization and laying performance of exotic chickens

Berhane Mekete Bogale and Tesfaye Engida D¹

Department of Animal Sciences, College of Agriculture, Food and Climate Science, Injibara University, P O Box 40 Injibara, Ethiopia
berhanemekete@yahoo.com
¹ Department of Animal Sciences, School of Agriculture, Guder Mamo Mezemir Campus, Ambo University, P O Box 19, Ambo, Ethiopia

Abstract

The high cost of commercial layer rations influence farmers' purchasing capacity to feed improved chickens. Hence, developing alternative least cost layer rations is crucial. So, this study was conducted to evaluate the effect of replacing essential amino acids and soybean seed with meat and bone meal on feed utilization efficiency and laying performance of egg production in exotic chickens. Ninety Bovans Brown layers were randomly allocated to three dietary treatments using a complete randomized design. Each treatment had two replicates comprising of 15 layers per replicate. The dietary treatments were: RC (control), chickens were fed purchased commercial layer ration; RF+SBS were fed newly formulated layer ration with the inclusion of essential amino acids and soybean seed while RF+MBM, 10 were fed newly formulated layer ration with the inclusion of 10% meat and bone meal. The chickens were fed ad libitum for 90 days. Data on hen day and hen housed egg production and different data used for calculation of feed utilization efficiency were recorded. Data were analyzed using SAS procedures of 2008-version 9.2 and Turkey's HSD multiple comparison techniques was used for means separation. Results of the study revealed that the control and RF+MBM,10 were more efficient in feed utilization as they consumed less dry matter feed (2.1g and 2.3g, respectively) to produce 1g of egg while RF+SBS was the least efficient as they consumed highest (p<0.001) dry matter feed (4.6g) to produce 1g of egg. The average hen day and hen housed egg production were the higher (p<0.001) in the control (87.2%) and followed by RF+MBM, 10 (75.4%) while it was the least (p<0.001) in RF+SBS (49.7%).Therefore, it is concluded that an alternative least cost layer ration for exotic chickens could be formulated with the inclusion of 10% of meat and bone meal in layer ration. Hence, it is recommended that the concerned institutions should provide practical training to the poultry farmers in formulation of such alternative layer ration.

Keywords: egg production, feed utilization efficiency, formulated layer rations, laying hens, locally available feeds

Introduction

Poultry production plays an important role in Ethiopia’s economy. It contributes significantly to employment opportunities, improving family nutrition by providing high-quality animal protein to the people, empowering women to maintain household food security, and creating cash income through the market exchange (Birhanu et al 2015). It also contributes to poverty alleviation and socio-economic inclusion of vulnerable groups such as the urban poor women, the disabled, orphans, and the unemployed to provide them with a decent livelihood (Ebsa et al 2019). However, the productivity per unit of bird and the contribution of the poultry sector to the national economy is relatively low (Nigussu et al 2019). This is mainly due to poor nutrition.

Tamasgen et al (2020) stated that the productive performance of chickens in Ethiopia is low due to different factors among which feed availability and quality is the major contributing factor. Thus, poultry nutritionists are doing great efforts to develop diets that meet the nutrient requirement, economical, efficiently sustain their immune system and improve the quality of poultry products. Hussein et al (2015) stated that nutrition is the most important aspect of poultry production that can be used to enhance the productivity and reduce the cost of production.

The feed cost is the major limiting factor in chicken production, which accounts for up to 70% of the total variable cost in intensive system of poultry production. Thus, the provision of fairly balanced low-cost diets based on farm produce that matches the genetic potential of improved chickens is of utmost importance to minimize production cost while still achieving reasonable profit from the enterprise (Tavares et al 2015).Thirumalaisamy et al (2016) stated that there is a need to improve the scientific knowledge for utilizing low-cost locally available agro-industrial by-products in poultry feed to reduce the feed cost. Any attempt to improve commercial poultry production and increase its efficiency, therefore, needs to focus on better utilization of the available feed resources.

Commercial feed prices have frequently increased, making it unaffordable for Ethiopia's small and medium-scale chicken producers. On the other hand, locally available feed sources have the potential to cover the gap when formulated with a cost-effective and nutritionally balanced diet (Tesfa 2020). Berhane and Tesfaye (2022) stated that the prices of different commercially formulated poultry rations have frequently increased and were not economical for small and medium-level poultry producers in Ethiopia and most other countries.

During the rearing and laying periods, the chickens should receive enough protein from both plant and animal protein sources to ensure optimum growth and subsequent performance. Meat and bone meal (MBM) has a high crude protein (CP) content ranging from 49.5 to 59.4% with a well-balanced amino acids profile including the limiting amino acids of methionine and cysteine for poultry (Hicks and Verbeek 2016). Niger seed (Guizotia abyssinica) is a protein rich feed with crude protein levels ranging from 22 to 42 percent (Heuzé et al 2016). A soybean (Glycine max) is the major source of protein in the diet of mono-gastric animals, which contains 37-38% CP on dry matter basis (Nahashan and Nthenge, 2013).

Feeding of exotic chickens with locally formulated layer rations that replace expensive feed ingredients of essential amino acids and soybean seed with relatively less expensive feed ingredients of MBM is highly indispensable to reduce the cost of layer rations. Such experiences could help the small and medium poultry farmers to achieve higher profits. However, there have been little or no research works conducted for replacing expensive feed ingredients of essential amino acids and soybean seed (SBS) with MBM in layer rations. Hence, the present research work was undertaken to investigate the effect of replacing expensive feed ingredients of essential amino acids and SBS with relatively less expensive feed ingredients of MBM on the efficiency of feed utilization and laying performance of exotic chickens

Materials and methods

Description of the study area

The research work was conducted in Ambo University Poultry Farm, Ambo town, West Shewa Zone, Oromia Regional State, Ethiopia. Ambo town is located approximately between 8 ^o 56'30’’ N- 8 ^o 59'30’’ N latitude and between 37^o47'30" E-37 ^o 55'15" E longitude. It is located 114 km away from Addi Abeba, the capital city of Ethiopia (Shanmugham and Tekele 2011; Gemechu 2013). The mean annual temperature and rainfall of Ambo town were 18.64^oC and 968.74 mm, respectively (Gemechu2013). The Ambo town has an altitude 2101 meters above sea level (Ogato 2013).

Experimental feed ingredients, feed preparation and formulated layer rations

The feed ingredients used to formulate experimental layer rations (RF+SBS and RF+MBM) were maize, wheat short, niger seed cake, MBM, SBS, essential amino acids (methionine, lysine and dicalcium phosphate), limestone, vitamin premix and salt (Table 1).The layer ration of RF+SBS was formulated with the inclusion of essential amino acids (methionine, lysine and dicalcium phosphate) and roasted SBS along with other feed ingredients. The layer ration of RF+MBM,10 was formulated by increasing the level of MBM to 10% along with other feed ingredients. But, the control layer ration (Diet commercial RC) was purchased from feed processing unit.

Before formulation of layer ration of RF+SBS, SBS were roasted on the metal pan using wooden materials as a source of heat energy to inactivate anti-nutritional factors such as trypsin inhibitor. The amount of maize, niger seed cake, soybean seed, and salt were weighed and crushed with feed mill to pass through a 5mm sieve size. The grounded feed ingredients as well as the previously grounded feed ingredients were added in the mixer machine based on their calculated proportion (Table 1) and then were thoroughly mixed. The two types of formulated layer rations (RF+SBS and RF+MBM) had similar iso-nitrogenous and iso-caloric contents (NRC 1994).

Experimental design and dietary treatments

A total of ninety Bovans Browns layers with similarage of 28 weeks and average bodyweight of 1.6 kg were selected from Ambo University Poultry Farm. The selected layers were randomly allocated to three dietary treatments in a complete randomized design (CRD). Each treatment had two replicates comprising of 15 layers per replication. The three dietary treatments were: RC, chickens were fed commercial balanced layer ration purchased from commercial feed processing unit; RF+SBS were fed layer ration formulated with the inclusion of essential amino acids and roasted SBS along with other feed ingredients, and RF+MBM were fed layer ration formulated with the inclusion of 10% MBM (without inclusion of essential amino acids and soybean seed, Table 1). The feeding trial was conducted for a period of 90 days.

Management of chickens

The layers were kept in a deep litter house partitioned into 6 pens with wire mesh and a hard board. Before the start of the experiment, necessary preparation interms of cleaning, disinfection and spraying against external parasites of all the pens and equipment were conducted. The concrete floor of each pen was covered with disinfected tef (Eragrostis tef) straw at a depth of 10cm as litter material and was equipped with laying nests, feeders, and waterers. The layers were kept in a deep litter house and fed weighted amount of feed on ad libitum basis (with 10% refusal) twice per day both at 7:30 AM and 2:30 PM. Clean tap water was also available at all the time and chickens were getting clean water on free choice. Generally, chickens had similar managerial and sanitary conditions during 90 days of the experimental period and all efforts were made to minimize pain and discomfort for the chickens.

Collection of samples and chemical analysis

Representative feed samples from each feed offered and refusals per pen were daily collected and pooled per treatment for the entire experimental period. The samples then were analyzed for dry matter, crude protein, ether extract, crude fiber, and total ash using the proximate method of analysis (AOAC 1990).The calcium and total phosphorus contents were determined by atomic absorption spectrophotometer and vanado-molybdate method, respectively (AOAC 1990).The metabolizable energy (ME) content was calculated by indirect method as described by Wiseman (1987) as follows: ME (Kcal/kg DM) =3951+54.4 Ether Extract (EE)–88.7 crude fiber (CF)–40.8 Ash.

Feed conversion ratio and egg production performance

Feed Conversion Ratio (FCR) is the parameter used for calculation of efficiency of feed utilization. Hence, different data were collected for this analysis, which include daily feed intake, dry matter percentage for each layer ration, number of eggs produced per day per replication and average egg weight per replication. The formula used for calculation of FCR is the following.

Egg production performance

Egg yield: Eggs produced were collected and recorded daily both in the morning and evening for each replication. The rate of egg production was calculated based on the average percentage of hen-day and hen-housed egg production for each replicate following the methods developed by Hunton (1995) as follows:

Note: HDEP = Hen-day egg production, HHEP = Hen-housed egg production

Egg weight and egg mass: The daily collected eggs per replication were weighed immediately using an electronic balance and the average egg weight was computed by dividing the total weight of eggs produced in each day per replication to the number of eggs produced per pen per day. Egg mass (g/hen/day) was calculated as the total weight of eggs produced in each day per replication divided by the number of hens per pen per day.

Data analysis

The collected data were analyzed using one-way analysis of variance (ANOVA) using general linear model of Statistical Analysis Systems (SAS) procedures of 2008-version 9.2. Differences among the treatment means were separated using Tukey’s Studentized Range Test (HSD) whenever ANOVA showed significant variation (p≤0.05) among the treatments. The following statistical model was used for the study: Yij = μ + Ti + eij; where: Yij = represents the j^th observation in the i ^th treatment level (response variables were feed intake, feed conversion ratio, egg production and egg weight); μ = overall mean, Ti = i ^th treatment effect (feeds) (i= 1, 2, 3); eij = random error

Results and discussion

Chemical composition of the feeds

The results of the chemical analysis of different feed ingredients used in formulation of layer rations of RF+SBS and RF+MBM and the nutritional composition of the layer rations for each treatment have shown in Table 2. The result of the chemical analysis indicated that MBM had the highest CP content (47.3%), followed by non-fried (41.9%) and fried SBS (40.9%), whereas maize grain had the lowest CP content (8.5%). The crude fiber (CF) contents were higher for non-fried SBS (17.7%), Niger seed cake (15.5%) and fried SBS (14.2%). On the other hand, maize grain had the least CF content (4.1%) and followed by MBM (4.5%). This study indicated that frying of SBS reduced the CF content to a considerable extent. To reduce the impact of anti-nutritional factors of SBS, it was fried before mixed with other feed ingredients. The energy contents (ME Kcal/kg of feed) of different feed ingredients were ranged from 2250 in meat and bone meal to 3480 in maize grain.

When the CP, CF and energy contents of diffent layer rations were considered, the CP contents were between 16.4% (RF+MBM) and 17% (RF+SBS), which were within the acceptable limits. The CF content of layer rations was higher in RF+SBS (7.2%) while it was the lowest in RC (5.2%). The energy contents (ME Kcal/kg of feed) of different layer rations were between 2820 and 2890 (Table 2).

As indicated in the current study, the higher CF content in RF+SBS layer ration being more than the normal level might have affected the performance of chickens. Varastegani and Dahlann (2014) stated that a higher level of CF in the layer's ration (maximum of 5%) impaired normal feed consumption, resulting in decreased egg production. On the other hand, at the normal rate of inclusion of CF (3–5%), insoluble fiber feeds such as cellulose and lignin improve the nutrient metabolism due to their ability to modulate gastric secretions from the proventriculus and muscular activity from the gizzard (Tejeda and Kim 2021).

The higher CP content and the lesser CF content of MBM in the current study were similar to the findings of Hicks and Verbeek (2016) who reported that the CP content of MBM was higher, ranging from 49.5 to 59.4 percent while the CF content was the least, ranging from 1 to 5.13 percent.

Efficiency of feed utilization and egg production performance

Efficiency of feed utilization: The feed conversion ratio (FCR) revealed that both RC and RF+MBM consumed less (p<0.001) dry matter feed (2.1 and 2.3g, respectlively) to produce 1g of egg while RF+SBS consumed the highest (p<0.001) dry matter feed (4.6g) to produce 1g of egg (Table 3). This finding indicated that the hens in the COM and treatment RF+MBM,10 were the most efficient in feed utilization for converting the feed to egg production than those layers which were fed RF+SBS layer rations, where they were the least efficient in feed utilization. The FCR values in the RC and treatment RF+MBM,10 in the current study were much lower than the reported values by Hussen et al (2015), where in their study the FCR values were between 3.7 and 5.7 in layer ration formulated to replace soybean meal (SBM) with processed kidney bean meal (PKB). The comparison indicated that the performance of hens in RC and RF+MBM,10 in the current study were most efficient in feed utilization. The difference in the efficiency of feed utilization might have been due to the differences in the types of layer rations, the environment condition and the breed difference.

Egg production performance

The average percentage of hen-day and hen-housed egg productions (per day per replication) were the highest (p<0.001) in the control (87.2%), followed by RF+MBM (75.4%) while it was the least (p<0.001) in RF+SBS (49.7%) (Table 3). The average egg mass (g/hen/day) followed the same trend to the egg production where it was the highest (p<0.001) in the RC (51.7g) and followed by RF+MBM (47.7g) while it was the least (p<0.001) in RF+SBS (31.1g).

The possible reasons for the higher egg production, egg mass and efficiency of feed utilization in RF+MBM could be due to higher protein and mineral contents and less CF rate of MBM. Hossain et al (2018) reported that MBM has a high content of PC (average 53% CP) and less FC content (average 2.6%, and in the range of 1.1 to 2.9%). Hicks and Verbeek (2016) also stated that MBM has a well-balanced amino acid profile including the limiting amino acids (methionine and cysteine) in poultry rations. They also reported that the ash/mineral content (calcium and phosphorus) of MBM was higher ranging from 20.7 to 52.9%. Zanu et al (2020) stated that MBM has a high source of protein, calcium, and available phosphorus for broiler diets. Similarly, Miles and Jacob (2011) also stated that MBM has high calcium, available phosphorus, and lysine contents and can be included in layer ration up to 10%. Thus, the higher nutrient contents in layer rations of RF+MBM,10 as a result of inclusion of MBM in this treatment could have contributed to the better performance of chickens.

The other possible reasons for higher egg production performance of RF+MBM could be due to higher dry matter intake. In line with this, Berhane and Tesfaye (2022) reported that the mean daily dry matter intake (106.8 g) was higher (p<0.01) in RF+MBM, which was fed layer ration formulated with inclusion of 10% MBM than RF+SBS (102.6 g), which were fed layer ration formulated with the inclusion of essential amino acids and SBS along with other feed ingredients. Correspondingly, the final body weight, body weight change and body weight gain were higher (p<0.05) in RF+MBM than RF+SBS, indicating higher dry matter intake had great impact for best performance of chickens. The higher dry matter intake of RF+MBM10 might have been due to higher inclusion level (10%). In this regard, Hussen et al (2015) reported that feed intake was higher as a result of higher level of inclusion of processed kidney bean in layer rations by replacing 75% and 100% of soybean meal (SBM) than at lower level of replacement of SBM. The higher dry matter intake in RF+MBM could also be due to higher protein and mineral contents and less crude fiber content of MBM.

On the other hand, significantly lowest average dry matter intake, hen day and hen housed egg production and least efficient in feed utilization in RF+SBS could be due to relatively higher CF content of the layer ration (7.17%) as a result of high CF of fried SBS (14.15%). Melesse (2020) stated that dietary crude fiber (CF) has been considered as diluents of the diets and often an anti-nutritional factor. Varastegani and Dahlann (2014) also found that a higher level of CF in the layer's ration impaired normal feed consumption, resulting in decreased egg production. These authors described that the CF content in poultry rations should be between 3 and 4% with a maximum of 5%. Jha and Mishra (2021) stated that higher fiber diets usually mean relatively low energy density that may decrease feed intake, feed conversion ratio, and body weight gain of poultry.

Besides, the possible reasons for significantly least dry matter intake, least efficiency of feed utilization, and egg production performance of RF+SBS could be due to the anti-nutritional factors of SBS. Liener (1994) and Han et al (1991) stated that raw SBS is known to have anti-nutritional factors like trypsin, which interfere with protein absorption, depressing feed intake, growth rate, and feed utilization efficiency in animals. According to Pitala et al (2016), raw SBS contains anti-nutritional elements (trypsin being the most common) that impair poultry performance. Bueno et al (2018) also stated that the use of SBS is limited by the presence of anti-nutritional factors, where it affects the growth of mono-gastric animals. The above stated findings about SBS indicated the negative effect of anti-nutritional factors which might have had contributed for decreased in dry matter intake, least in feed utilization efficiency and lowest egg production performance of the treatment RF+SBS.

Conclusions and Recommendations

Based on the finding of the study, it has been concluded that an alternative least cost layer ration could be formulated for poultry farmers by inclusion of 10% meat and bone meal in layer rations. Therefore, it is recommended that the concerned institutions should provide frequent practical training in the formulation of this alternative layer rations to small and medium-scale poultry farmers.

Acknowledgment

The authors would like to deeply acknowledge and express our immense sense of gratitude to Ambo University for full financial sponsorship and providing the necessary facilities to carry out the research work. We also deeply acknowledge and highly appreciate Professor Endrias Zewdu Gebremedhin and Habtamu Ashagre Asmare (Assoc. Prof.), for their constant encouragement and comments during the write-up of the article.

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