The Effect of Silkworm Pupae (Bombyx Mori) Meal to Substitute Fish Meal on Production and Physical Quality of Quail Eggs (Cortunix Cortunix Japonica)

The aims of this study was to determine the effect of substitution of fish meal protein withsilkworm pupae (Bombyx mori) on quail performances and egg quality. The experiment was a completlyrandomized design (CDR) with four treatments and four replications and ten birds of each replication.The treatment diets were R0: diet contain 8% fish meal, without silkworm pupae (control), R1: dietcontain silkworm pupae subtituted of 25% fish meal protein, R2: diet contain silkworm pupae subtitutedof 50% fish meal, protein and R3: diet contain silkworm pupae subtituted of 75% fish meal protein. Theresults showed that substitution of 25% up to 75% significantly (P<0.05) reduced feed conversion ratio,significantly (P<0.05) increased egg production and did not affecting physical quality of quail eggs. Inconclusion, silkworm pupae can be used 25% up to 75% replacing protein fish meal.


INTRODUCTION
Livestock is one of the important business in an effort to meet the needs of animal protein for the people. One important factor is the availability of feed. The availability of feed must be guaranteed in quality, quantity, and continuity. In addition, the price of raw materials is also a concern in the preparation of rations that will have an impact on the cost of production. Fish meal is the animal protein supplements most widely used by the feed industry.
Feed industry in Indonesia need fish meal about 100,000-120,000 tons per year and most of it is fulfilled with imported one as much as 50,000-65,000 tons (Statistic Indonesia, 2012). This amount would require a very large foreign exchange. Price of imported fish meal was almost the same as the local fish meal, but imported fish meal has a better quality. This makes not a lot of local fish meal used in feed industry, so the price becomes expensive. The quality of local fish meal is very low with crude protein content below 55% (National Standardization Agency of Indonesia, 1996) and it becomes an important constraint. Therefore, it needs a solution to reduce the use of fish meal by substituting with high quality ingredient and affordable prices. One of the ingredient that can be used is industrial waste such as silkworm pupae.
Silkworm pupae is potential to be used as animal feed. The average cocoon production in Indonesia since [2005][2006][2007][2008][2009] , 2011). Although the product is still relatively small, the potential in the future can still be developed, because Indonesia still imports the silk fabrics from other countries. Recorded in 2009 the national silk yarn needed 900 tons/year. South Sulawesi, for example, requires about 250 tons per year and will be met from local production of about 15.789 kg. In South Sulawesi centers silkworms just focused on Soppeng, Wajo, and Sidrap. Mulberry plants are grown in other districts such as Barru, Bone, Enrekang, Bulukumba, and some other districts with a total area of 2.524,8 acres has not been developed as a silkworm cultivation. The development of silk industry in the future by increasing the production of yarn, waste silkworm pupae production will also increase, so that is potential to be animal feed.
Waste from silk industry is widely used today is the silkworm wrapper. Utilization of this waste in Indonesia is only for the manufacture of accessories. The pupae will quickly rot and cause the unpleasant smell that can be pollution to environment. In some countries such as Korea, Japan, and China silkworm pupae has been used as snacks, canned food, alternative food diabetics, candles, and beauty products such as soaps and hair tonic. As recorded, Chinese people started cultivating artificial Bombyx mori L. 5200 years ago, eating insects 3200 years ago, people in Jiangsu, Zhejiang and the three northeastern provinces areas like the edible chrysalis Bombyx mori L. (Yi et al., 2010). It is make researchers interest to study about silkworm pupae. Some research have been done indicated that silkworm pupae contain high nutrients. Pereira et al. (2003) reported that silkworm pupae meal contain 51.1% of crude protein and 34.4% of crude fat. Silkworm pupae also have a good EAA (essential amino acids) content, such as EAA from silkworm Antheraea pernyi (406.2 mg/g protein), Bombyx mori (431 mg/g protein) and that is higher than that of egg (388.2 mg/g protein) (Zhou and Han, 2006). Which such that quality, silkworm pupae potential as an alternative feed ingredients.
Silkworm pupae also contain 32.52% of saturated fatty acids and 67.48% of unsaturated fatty acid with linoleic acid (omega 6) 8.57% and linolenic acid (omega 3) 24.4% (Pereira et al. 2003). Both types of unsaturated fatty acids have been a lot of concern for people considering the benefits for the body. Handini et al. (2006) suggested that increasing consumption of omega-3 can reduce the risk of death due to cardiovascular disease (atherosclerosis and coronary heart disease), cancer, tumors and may improve the body's immune system. Deficiency of fatty acid can cause interference with the nervous system and visual abilities. Deficiency of omega-6 also have an impact on health such as slow growth and skin sores or flaky (Gopper et al. 2009).
Egg is one of the many farm products consumed by the public, egg has a complete nutrient content and good biological value. According to Vaghefi (2002), eggs contain protein, fat, water, some vitamins such as vitamin A, B, D and E as well as minerals such as P, Mg, Fe, Cu, and Zn which are beneficial for the body. One of the many eggs that are consumed was quail eggs. The nutrient content of eggs can be enhanced by the provision of a quality diet. The one solution to increase the quality diet is by giving silkworm pupae meal which high in protein and unsaturated fatty acids. Giving silkworm pupae meal can be done by substitution of fish meal. The aim of this study was to determine the effect of substitution of protein fish meal with silkworm pupae (Bombyx mori) on quail performances and egg quality.

Perum
Perhutani Unit 1, Telogowungu, Central Java. The upper silk layer was discarded by cutting the upper layer, then the pupae were sun dried and ground to be powder. The feeding trial in this experiment used 160 quails pullet.
The experiment was a completly randomized design (CDR) with four treatments and four replications with ten quails of each replication those were place in 60 x 60 x 40 cm pen The diet treatments were R0: diet contained 8% of fish meal, without silkworm pupae (control), R1: diet contained silkworm pupaeto subtitute 25% of fish meal protein R2: diet contained silkworm pupae to subtitute of 50% fish meal protein, and R3: diet contained silkworm pupae to subtituteof 75% fish meal protein. The diets were formulated iso caloric and iso protein according to recommendation of Leeson and Summers (2005) ( Table 1).
Quails were reared for ten weeks, one week for environmental adaptation, one week for adaptation treatment and eight weeks for diet treatment. Diet and drinking water were offered ad libitum. Feed intake was measured every week, egg production and egg weight recorded every  day during the treatment. Physical quality of egg was observed at the first , second , third , fourth, and eighth week of the treatment. Three eggs were taken from each replication for physical quality analysis. The variable observed in this study were quail performance: feed consumption, quail day egg production, egg mass production, feed conversion, and egg physical quality.

Statistical Analysis
Data obtained were analyzed by analysis of variance (ANOVA), if there was a significant different, the data were further analysed using Duncan's multiple range test (Mattjik and Sumertajaya, 2002).

Feed Consumption
The statistical analysis showed that the treatments did not affect the feed intake. Feed consumption on this experiment was 15.03-16.60 g/bird/day higher than consumption on Suripta et al. (2007) is 15.4 g/bird/day. According to Dewi and Setiohadi (2010) feed intake was influenced by several factors such as age and size of bird, palatability and feed quality. It indicated that fed silkworm pupae meal did not affect the feed palatability. Silkworm pupae meal has similar texture, smell, and quality as fish meal. Feed consumption of laying hens fed silkworm pupae meal of 100% replaced fish meal protein (8% in the diet) differ markedly lower than that of fed 25-75% replace fish meal protein (Mangisah et al., 2004).

Egg Production
The results showed that subtitution of 25% or 75% fish meal protein with silkworm pupae (R1 or R3) significantly increased egg production (P<0.05) compared to R0. Egg production at R0 significant lower than R1 and R3, but not significantly different with R2. Egg production in R0 lower than another treatments in line with the low feed intake, that was influanced with nutrient consumption. Energy consumption was not different between treatments (P>0.05). However, any different on protein consumption, that could be astimate affected egg production among the treatments. Table 2 shows that R0 has a lower real protein intake (P<0.05) compared to R1, R2, and R3. Low consumption of proteins in R0 may be caused by a low quality protein in R0 diet compared ration protein quality in R1, R2, and R3 diet. Substitution of fish meal with flour pupae could be expected to improve the quality of diet. Silkworm pupae have lower protein (51.1%) compared to fish meal (60% protein). Despite silkworm pupae have lower crude protein content, metabolizable energy content, unsaturated fatty acids, and amino acid composition of silkworm pupae higher than fish meal (Leeson and Summers, 2005;Pereira et al. 2003). Wijayasinghe and Rajaguru (1977), diet contain 7.5% silkworm pupae have protein and amino acid value same with diet containing 10% of fish meal and 2% of skim milk. Chicken egg production by administration of silkworm pupa meal as much as 6% was significantly higher (P<0.01) in comparison with diet without silkworm pupae meal. The egg production with diet silkworm pupae significant difference suggests that the quality of silkworm pupae protein was better than protein concentrate for laying hen (Khatun et al., 2005). Mangisah et al. (2004) showed that substitution of silkworm pupae meal replace 25-75% of fish meal protein in the diet was not significantly different from controls. Total egg production for research on R0 is also markedly lower than the R1, R2, and R3, the highest production in R1. This is consistent with the value of the daily egg production R1 higher than the other treatments. Egg production is influenced by a combination of saturated fatty acids and unsaturated fatty acids on diet. According to Wathes et al. (2007), unsaturated fatty acids such as eicosapentaenoat (EPA) and arachidonat fatty acid (AA) were importent precursor for prostaglandin, prostacycline, thromboxane, and leukotriene. Prostaglandins such as FSH (folicel stimulating hormone) and LH (leutinizing hormone) have been implicated in many reproductive functions (Abayasekara and Wathes, 1999).

Feed Conversion
Feed conversion expressed as feed required per kg of egg mass. The amount of feed conversion in layer is determined by the amount of feed intake, egg number and weight of eggs produced. The average of feed conversion in this study is 3.35-4.21 (Table 3). Feed conversion in treatments of R1, R2, and R3 are markedly lower than control (R0) (P<0.05). This was because the daily and total egg production on R1, R2, and R3 were higher than R0. Substitution of silkworm pupae meal did not affect the feed efficiency. Substitution of silkworm pupae meal replace fish meal up to 75% in laying hens diet had a feed conversion rate equal with control (Mangisah et al., 2004). This is estimate due to the subtitution of silkworm pupae meal make nutrient contain on diet better. Amino acids and unsaturated fatty acids from silkworm pupae supplement nutrient diet content. The content of amino acids and essential fatty acids on diet can promote high productive performance in broiler chicken (Jintasataporn, 2012)

Egg Physical Quality
Egg physical quality were observed as egg weight, yolk color score, Haugh unit, egg white weight, yolk weight, shell weight, and shell thickness. The observation and analysis of variance of each variable are presented in Table 4. Substitution of silkworm pupae meal was not significantly different (P>0.05) in scores yolk color, Haugh unit, yolk weight, shell weight, and shell thickness. However, the substitution of silkworm pupae meal significant effect on increasing egg weight and egg white weight (P<0.05).
Yolk color scores were not different indicating that substitution of silkworm pupae meal does not affect the color of egg yolks. Yolk color is influenced by the presence of pigment xanthophylls, lutein, zeaxanthin, as well as synthetic pigments such as canthaxanthin and apocarotenoic esters in the feed. Feed ingredients rich in xanthophylls are corn and corn gluten meal (Leeson and Summers, 2005). Yolk color scores were not different because the amount of corn on diet have same ration. Haugh unit is a value that determines the quality of egg freshness. The average of Haugh unit in this study is 92.01 -92.72 (Table 4) and that value was higher than the results of the study by Dudusola (2010), that was 84.19. The analysis showed that the Haugh unit values were not significantly different between treatments. It is demonstrated that substitution of silkworm pupae meal does not affect the quality of the eggs. In this research results showed that the egg include in grade AA. According to Yuwanta (2004), egg Haugh unit values above 72 are categorized egg quality AA, Haugh units 60-72 A quality eggs, Haugh units 31-60 B quality eggs, and Haugh unit values less than 31 egg quality C. Haugh unit value which did not differ due to each egg is stored in the same place and time. Factors that affect the value of Haugh units of which time and place of storage of egs, age and type of livestock, nutrient feed, disease, and supplementation (vitamins C or E) and diseases (Roberts, 2010;Gerber, 2006).
Yolk weight associated with egg weight, egg white weight, and shell weight. Egg yolk and shell weight did not differ between treatments, but the egg white weight different between treatments. The differences of egg white weight is in line with the different of egg weight between treatments. This suggests that the largest composition of egg is white egg. Weight and eggshell thickness were not different between treatments, it may be caused by calcium content in the diet to be similar. Calsium is the major component in egg shell (Shen and Chen, 2003). Egg shell quality is influenced by the availability of Ca and P. Both of the minerals aimed at optimizing shell calcification.
The higher the calcium concentration in diet, the better shell quality and shell thickness (Leeson and Summers, 2001).
The average of egg weight of this study ranged from 8.40-8.92 g / egg. The result showed that egg weight in R2 was significantly higher than R0, R1, and R3 (P<0.05). Egg weight was lower than the results of the study by Song et al. (2000) that is 10.34 g. Egg weight associated with the type of quail. According to Hrncar et al. (2014), eggs from quail meat type (13.06 g) was bigger than eggs laying type (11.48 g). The others factors are the weight and age of livestock, energy content, fat, linoleic acid, protein, and amino acids such as methionin (Leeson and Summers, 2005). Silkworm pupae meal contains linoleic acid 8.57% and linolenic acid 24.4%, with the total unsaturated fatty acids 67.48% (Pereira et al., 2003). The average of egg whites during this study can be seen in Table 4. The results showed that the egg white weight was significantly, R2 higher than R1 and R3, but not different from R0. This is consistent with the egg weight was produced. The heavily of egg white weight influenced by the egg weight. Heavy egg white in the study ranged 4.37-4.89 g with the percentage of egg white weight is 53.20-54.62%. According to Yuwanta (2010), normal range of quails egg white weight is 4.1-6 g per egg with egg white weight percentage of 52-60% from hole egg.

CONCLUSION
Subtitute silkworm pupae meal 2.08% to 6.25% to replace of 25-75% fish meal protein given a good results in terms of egg production, feed conversion, without negative effect on egg quality.