| Livestock Research for Rural Development 27 (5) 2015 | Guide for preparation of papers | LRRD Newsletter | Citation of this paper |
This research aims to examine the effects of the protein level in a variety of protein sources (soybean meal and poultry meat meal) on the growth of broiler chickens. It used 192 one-week old unisex broiler chickens, strain CP 707. In this research, 6 (six) types of treatment feed were used with the addition of amino acids, namely lysine and methionine, so that the level of lysine by 1.2% and the level of methionine by 0.6% were met. The treatment feed consisted of SBM16: the protein level by 16% derived from a plant-based protein source (i.e. soybean meal), PMM16: the protein level by 16% derived from an animal-based protein source (i.e. meat meal), SBM19: the protein level by 19% derived from a plant-based protein source (i.e. soybean meal), PMM19: the protein level by 19% derived from an animal-based protein source (i.e. meat meal), SBM22: the protein level by 22% derived from a plant-based protein source (i.e. soybean meal), and PMM22: the protein level by 22% derived from an animal-based protein source (i.e. meat meal). The research design used was a completely randomized design with six treatments and four replications. The research variables examined were feed intake (g/chick/day), weight gain (g/chick/day), feed conversion, carcass percentage (%), abdominal fat percentage (%) and the total amount (N) of excreta. The data obtained were then analyzed in terms of the variance, when differences were found, the analysis was then continued by performing the Duncan’s Multiple Range Test or DMRT.
The findings suggest that feed treatment provides major effects on daily weight gain, feed intake, feed conversion, carcass percentage, abdominal fat percentage and the total amount (N) of excreta. The best feed that generates the highest daily weight gain, carcass percentage and feed conversion is feed which contains 19% and 22% protein levels derived from an animal-based protein source, i.e. Poultry Meat Meal. Feed intake using a plant-based protein source, i.e. soybean meal which contains a 22% protein level is not recommended.
Keywords: performances, sources of animal-based protein, sources of plant-based protein
Feed is one of the factors which determines the poultry production and the success of the poultry business. Intensive poultry rearing really affects the production costs incurred especially for feed costs which amount to 65 to 70% of the total production costs. The feed costs for energy needs reach 70% and for protein and amino acid needs, the costs reach 25% while the remaining 5% is comprised of the costs of vitamins and minerals (Sibbald 1987).
To reduce the protein level is one way to cut the feed costs as protein is the most expensive part. However, this causes decreases in the weight gain and increases the abdominal fat (Diambra and McCartney 1985). The use of feed which contains a low level of protein should be supplemented especially with essential amino acids.
Based on its sources, there are two sources of protein, namely animal-based protein and plant-based protein. The first source of protein generally has a more complete nutrient content to meet the needs of amino acids and minerals. Unfortunately, it is expensive and may lead to high feed costs. Conversely, plant-based protein is relatively cheaper and sometimes has a good amount of nutrient content as well. But, it lacks essential amino acids such as lysine and methionine (Kompiang 1982). This requires that the use of plant-based protein sources as feed should be supported with the addition of amino acids.
Methionine supplementation on low-protein feed which is derived from soybeans, according (Summer et al 1987), provides benefits and can also reduce feed costs. The advantages which this soybean meal has are that its protein and amino acid levels are high (Elangoan and Shim 2000) and it is much cheaper than animal-based protein sources. The use of soybean meal as a protein source in broiler chicken feed leads to good growth if supported with the addition of methionine, substitution of fish meal with soybean meal which is supported with the addition of methionine does not make significant differences in terms of the resulting growth.
This research aims to examine the effects of the protein level in a variety of protein sources (soybean meal and poultry meat meal) on the growth of broiler chickens.
The research was carried out for 6 weeks consisting of 1 week of an adaptation period and 5 weeks of an observation period. The materials used in this research were 192 one-week old unisex broiler chickens, strain CP 707. The feed constituents were comprised of corn yellow, fine bran, soybean meal (SBM), meat meal (Poultry Meat Meal), coconut oil, calcium carbonate, biofos, NaCl, Mineral B12, and filler with the addition of the amino acids of L-lysine HCl and DL-methionine. The type of cage used in this research was group battery cages in which each plot has the following dimensions: 1 x 1 x 0.5 m, as many as 24 cages.
The preparations before initiating the research were cleaning the cages and having the cages disinfected using disinfectants. To prevent the Newcastle Disease, vaccinations were given using Medivac ND Hitchner B-1 manufactured by Medion Bandung via eye drops at the age of 3 days and drinking water at the age of 21 days with Medivac ND La Sota. Besides, the poultry was vaccinated against the Gumboro Disease at the age of 2 weeks via drinking water.
In this research, 6 (six) types of treatment feed were used with the addition of amino acids, namely lysine and methionine, so that the level of lysine by 1.2% and the level of methionine by 0.6% were met. The composition of the feed given in this research along with the nutritional information are presented in Table 1. The treatment feed consisted of:
SBM16: protein level by 16% with SBM
PMM16: the protein level by 16% with PMM
SBM19: the protein level by 19% with SBM
PMM19: the protein level by 19%
with PMM
SBM22: the protein level by 22% with SBM
PMM22: the protein level by 22% with PMM
| Table 1. The feed composition used in the research | ||||||
| Materials (%) | Treatment | |||||
| SBM16 | PMM16 | SBM19 | PMM19 | SBM22 | PMM22 | |
| Yellow Corn | 53.0 | 53.0 | 48.3 | 52.7 | 33.8 | 49.0 |
| Fine Bran | 24.7 | 24.6 | 19.0 | 18.6 | 24.1 | 17.0 |
| Soybean Meal | 17.2 | 0.00 | 25.8 | 0.00 | 34.6 | 0.00 |
| PMM | 0.00 | 12.5 | 0.00 | 19.2 | 0.00 | 25.5 |
| Coconut Oil | 1.00 | 1.00 | 2.50 | 1.00 | 4.26 | 1.00 |
| CaCO3 | 1.50 | 0.70 | 1.50 | 0.30 | 1.40 | 0.00 |
| Biofos | 0.70 | 0.30 | 1.40 | 0.10 | 1.00 | 0.00 |
| Mineral B12 | 0.50 | 0.50 | 0.50 | 0.50 | 0.50 | 0.50 |
| DL-Methionine | 0.34 | 0.32 | 0.31 | 0.27 | 0.26 | 0.22 |
| L-Lysine HCl | 0.58 | 0.67 | 0.34 | 0.46 | 0.05 | 0.23 |
| NaCl | 0.50 | 0.50 | 0.35 | 0.50 | 0.00 | 0.50 |
| Filler | 0.00 | 5.91 | 0.00 | 6.37 | 0.00 | 6.05 |
| Total | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 |
| E.M (kcal/kg) | 3,020 | 3,006 | 3,001 | 3,004 | 3,004 | 3,006 |
| PK (%) | 16.0 | 16.0 | 19.0 | 19.0 | 22.0 | 22.0 |
| Ca (%) | 1.03 | 1.04 | 1.03 | 1.06 | 1.00 | 1.11 |
| P (%) | 0.50 | 0.58 | 0.52 | 0.59 | 0.50 | 0.62 |
| Lysine (%) | 1.20 | 1.20 | 1.20 | 1.20 | 1.20 | 1.20 |
| Methionine (%) | 0.60 | 0.60 | 0.60 | 0.60 | 0.60 | 0.60 |
This study was prepared by completely randomized design with six treatments and 4 replicates (Steel and Torrie 1989) requiring as many as 24 units of the cage. Each unit will be filled enclosure 8 tails so that the number of broiler chickens entirely as much as 192 birds.
The research variables examined were feed intake (g/chick/day), weight gain (g/chick/day), feed conversion, carcass percentage (%), abdominal fat percentage (%) and the total amount (N) of excreta. The data obtained were then analyzed in terms of the variance, when differences were found, the analysis was then continued by performing the Duncan’s Multiple Range Test or DMRT.
The results for the analysis of variance reveal that protein sources and protein levels are significantly different (P <0.05) in terms of feed intake. Based on the Duncan’s Multiple Range Test (Table 2), it is obvious that the best feed which produces optimal feed intake is PMM19 (the protein level by 19% derived from PMM as the protein source) and PMM22 (t the protein level by 22% derived from PMM as the protein source), while SBM22 (the protein level by 22% derived from soybean meal as the protein source) is the feed with the lowest intake.
The research findings suggest that feed intake in treatment SBM22 is low (the protein level by 22% derived from soybean meal as the protein source). This is presumably because soybean meal contains a number of antinutritional factors, including trypsin inhibitor (TI), a non-digestible carbohydrates, lectins, saponins, phytates (which bind calcium and protein making them hard to digest), and the type of protein which causes allergies, saponins and oligosaccharides (which cause abdominal bloating) which disrupt feed intake and nutrient utilization (Frikha et al 2012; McDonald et al 2010). The negative effects of the use of soybean meal is quite significant, which reach 34.6% while at the protein levels of 16% and 19%, the resulting negative effects are not so significant that the poultry is still ble to digest, i.e. 17.2% and 25.8% each, respectively.
| Table 2. The average daily feed intake, daily weight gain and feed conversion in 1 to 6 week old Broiler chickens | ||||
| No. | Treatment | Feed Intake (g/chick/day) |
Daily Weight Gain (g/chick/day) |
Conversion |
| 1 | SBM16 | 59.1b | 24.1b | 2.54a |
| 2 | PMM16 | 86.8d | 32.7c | 2.66a |
| 3 | SBM19 | 73.3c | 32.6c | 2.26a |
| 4 | PMM19 | 94.6e | 41.5d | 2.28a |
| 5 | SBM22 | 39.8a | 5.59a | 7.35b |
| 6 | PMM22 | 99.7e | 45.1d | 2.22a |
| SEM | 4.54 | 2.77 | 0.40 | |
| P | 0.00 | 0.00 | 0.00 | |
| Description: different letters in the same row and column indicate highly significant differences (P <0.05) | ||||
In relation to the animal-origin protein (PMM16, PMM19 and PMM22), it is revealed that the higher the level of protein the feed contains, the more significant increases in the feed intake. This is consistent with the studies reported by (Rohaeni et al 2003; Hargis and Creeger 1980; Sari 1998). The feed intake of the poultry is affected by the feed composition and the ambient temperature as well as the age and type of the poultry, the balance of energy and the protein level in the feed.
The results for the analysis of variance indicate that different protein levels and sources bring significantly different effects (P <0.05) on the daily weight gain. The Duncan’s Multiple Range Test results (Table 2) show that the feed PMM19 and PMM22 generate the best/ most optimal daily weight gain while SBM22 (where the protein level is 22% derived from soybean meal as the protein source) results in the lowest one. These findings indicate that the higher the level of protein the feed contains the higher the daily weight gain, except for SBM22, despite its 22% protein content, which is caused by the use of soybean meal.
In this research, the daily weight gain increased depending on the protein level which the feed contained. This is consistent with studies reported by (Kartikasari 2000; Cabel and Waldroup 1990) that the higher the protein level the feed contains, the more increasing the weight gain. According to Patrick and Schaible (1980), what determine the level of the biological values in proteins are the number of the materials used, the types and balance of amino acids. It is also stated that the balanced level of amino acids is highly influenced by the amino acids which the feed contains, the digestibility level of protein and availability of amino acids.
In relation to the protein sources, it is revealed that animal-based protein provides more significant weight gain than plant-based protein. These findings are consistent with the study by (Anwar et al 1979) that feed made from plant-based protein sources results in significantly lower weight gain in chickens of the starter phase compared to the feed made from animal-based protein sources. Treatment using feed made from plant-based protein sources which contain a 22% protein level (SBM22) results in significantly lower weight gain than the feed which contains 16% and 19% protein levels. The low daily weight gain occurs since poultry cannot consume food in quantities sufficient to meet its needs, the low levels of feed digestibility and absorption due to the soyin content found in soybean meal which binds methionine so as to result in low feed intake and inoptimal growth (Patrick and Schaible 1980). These findings imply that the use of soybean meal as a protein source in poultry feed by 34.6% is less efficient because it does not lead to optimal growth. According to Ravindra and Blair (1992), soybean meal is a good plant-based feed constituent since it contains a balanced composition of protein and amino acid. However, the biological value of the protein it contains is only equal to 60% (SCA in Surisdiarto et al 1998). In addition, soybean meal contains phytic acid which can survive the process of soybean meal manufacturing (Swick 1994). What limits the use of soybean meal is the presence of antinutritional substances suc as oligosaccharides which are difficult to digest and can cause abdominal bloating both in humans and animals (Reddy et al 1980; Fleming 1981). This suggests that sources of plant-based protein, especially soybean meal, are not as effective as feed made from animal ingredients or a mixture of both. According to Wahyu (1985), the use of animal-based feed ingredients offers a number of advantages such as high levels of calcium and phosphorus content, the presence of vitamin B-complex especially riboflavin and rich in vitamin B-12, methionine and lysine.
Based on the analysis of variance, it is found that the treatments make differences in terms of feed conversion. The Duncan’s Multiple Range Test results suggest that the feed which contains a 22% protein level derived from soybean meal as the protein source (SBM22) provides the highest feed conversion or the most inefficient one compared to the other protein levels (Table 2).
The findings of the research by (Sukmaningsih 1997; Sari 1998) report that feed conversion increases if the level of protein in the feed is low. Based on the sources of protein used from which the feed is made which contain a variety of protein levels, significant results are not found, except for SBM22. This indicates that the feed constituents used affect feed intake, feed conversion and weight gain of the poultry. According Nesheim et al (1979), feed conversion is influenced by the balance of the nutrients in the feed, body size and ambient temperature, the ability to digest nutrients the feed contains, and decreases in the feed nutrients during the metabolism process.
The results for the analysis of variance on the carcass percentage reveals that it is significantly affected by the feed treatment, the Duncan’s Multiple Range Test results are shown in Table 3. The feed with the highest carcass percentage is SBM19 (a 19% protein level in which the feed is made from soybean meal as the protein source) which is not significantly different from PMM19 and PMM22. A number of studies have shown that higher the protein level, the higher the carcass percentage (Jackson et al 1982; Sari 1998; Kartikasari 2000). The findings of the present research suggest that increases in the protein the feed contains will result in increases in the carcass percentage, except for SBM22. This implies that the carcass percentage at the 22% protein level (SBM22) is lower than that of the 19% protein level. This is resulted from the high use of plant-based protein sources (i.e. soybean meal) which generally decreases the percentage of carcass. This shows that the use of feed made from plant-based sources (i.e. soybean meal) should not be too high because it cannot provide optimal growth.
| Table 3. The average carcass percentage, abdominal fat percentage and blood cholesterol level in 1 to 6 week old broiler chickens | ||||
| No. | Treatment |
Carcass (%) |
Abdominal Fat (%) |
Total Amount (N) of Excreta (%) |
| 1 | SBM16 | 63.1bc | 2.38abc | 3.06a |
| 2 | PMM16 | 61.6ab | 3.50c | 2.83a |
| 3 | SBM19 | 66.9d | 1.73ab | 3.71b |
| 4 | PMM19 | 64.9cd | 3.19bc | 3.22a |
| 5 | SBM22 | 60.1a | 0.99a | 5.76c |
| 6 | PMM22 | 64.2bc | 2.29abc | 3.87b |
| SEM | 0.56 | 0.26 | 0.21 | |
| P | 0.00 | 0.03 | 0.00 | |
| Description: different letters in the same row and column indicate highly significant differences (P <0.05) | ||||
Results for the analysis of variance on the percentage of abdominal fat show that treatments bring significant effects on the percentage of abdominal fat. The Duncan’s Multiple Range Test results are shown in Table 3. The feed treatment in SBM22 results in a very low abdominal fat percentage while in PMM16, it results in the highest abdominal fat percentage. These results indicate that the higher the level of protein in the feed, the lower the percentage of abdominal fat produced. This is consistent with the research by Jackson et al (1982), Marks and Pesti (1984), Widhiharti (1987), Kartikasari (2000),as well as Heath et al (1980).
Compared to animal-based protein sources (i.e. PMM), plant-based protein sources (i.e. soybean meal) result in a percentage of abdominal fat which is not statistically different in relation to SBM16 and PMM16 or SBM19 and PMM19 and between SBM22 and PMM22. However, there is a tendency that feed made from animal-based protein sources has a higher abdominal fat percentage than the feed made from plant-based protein sources. This is consistent with the high weight gain since weight gain and abdominal fat has a positive correlation with a coefficient value by 0.4 (Leenstra, 1984). The percentage of carcass and abdominal fat is influenced by the ordo, sex, feed composition, age, ambient temperature, weight, quality and quantity of feed, energy consumption, the balance of energy and protein consumption as well as amino acid balance (Sonaiya and Benyi 1983 and Diwyanto et al 1980).
Results for the analysis of variance suggest that feed treatments bring significant effects on the total amount (N) of excreta produced. The Duncan’s Multiple Range Test results are presented in Table 3. In relation to the protein level the feed contains, the higher the level of protein the more significantly increasing the total amount (N) of excreta produced. The feed treatments in SBM16, PMM16 and PMM19 generate a significantly lower amount (N) of excreta compared to the amount (N) of excreta produced by the other treatments. Treatment SBM22 produces a significantly higher amount (N) of excreta compared to the amount (N) of excreta produced by the other treatments. A high protein level in the feed is not necessarily more efficient because not all of the protein is digested, some are sent out as excreta. This is consistent with the research by Morran et al (1992), Sukmaningsih (1997) as well as Summer and Leeson (1993) that the total amount (N) of excreta indicates an estimated excess of protein consumption. It may indicates the estimated excess of protein consumption which exceeds the protein need (Scott et al 1982), an excess in amino acid consumption or imbalanced consumption of amino acids (Murray et al 1995). The findings of this research indicate that the feed SBM22 is a waste because it cannot provide the optimal weight gain. Moreover, the amount (N) of excreta produced is significantly higher than the 16% and 19% protein levels which results in a higher level of environmental pollution.
The total amount (N) of excreta produced by chickens fed with animal-based protein sources is significantly lower that those fed with plant-based protein sources (soybean meal) except for feed with a 16% protein level (the resulting difference is not significant). This shows that the levels of digestion and absorption of feed made from animal-based protein sources are higher than those of feed made from plant-based protein sources.
Based on the research findings, the following conclusions can be drawn:
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Received 23 February 2015; Accepted 8 March 2015; Published 1 May 2015