Meat Fatty Acid and Cholesterol Content of Native Indonesian Muscovy Duck Fed with Rice Bran in Traditional Farm

Fat, cholesterol and fatty acid profile of breast and thigh meat of 12 Muscovy ducks (6 drakes) aged 8 weeks from the local farm in Bogor, West Java were analyzed in thus study. In general, Muscovy ducks were fed with rice bran twice a day and free-ranged in the backyard. The nutrition of rice bran is varied in crude protein, crude fiber, fat, and ash content. Muscovy ducks were slaughtered and the percentage of carcass weight, fat, cholesterol and fatty acid profile of the breast and thigh meat were measured and analyzed. The result showed that the breast meat had higher (P<0.05) ω3 total fatty acid EPA (C20:5ω3) but DHA (C22:6ω3) and linolenic acid (C18:3ω3) were not significant compared to that of thigh meat. Concentration of linolenic acid in breast meat ranged from 0.26 to 0.51% of fat and 0.35 to 0.39% of fat in thigh meat. Linoleic acid (C18:2ω6) in breast and thigh meat was 7.64 - 10.73% and 5.17 - 13.93 % fat, respectively. DHA concentration ranged from 0.13-1.31% fat in breast meat and EPA in thigh meat was approximately 0.08-0.32 % fat. EPA was significantly higher (P<0.05) in breast meat (0.03-0.28 %) than thigh meat (0.05-0.08 %) The study produced ω 6:3 ratio ranged 6.50-24.14 and 8.94-31.64 in breast and thigh meat, respectively.


Introduction
Muscovy duck is one of common poultry that are commonly few in the rural communities together with other poultry such as chicken and duck. Muscovy ducks are generally still maintained traditionally generally fed with rice bran and sometimes mixture with rice from household waste. The purposes of raising Muscovy duck by the rural communities are to become an alternative food source and as a parent for incubating duck eggs. Muscovy duck livestock development has a great opportunity to become the source of meat. However, the consumers now have more attention to the nutritional composition of meat, such as fat, cholesterol and fatty acid profile.
One reason Muscovy duck meat demand is very slow to increase is the opinion that Muscovy duck meat has high content of fat and cholesterol which can lead to increased risk of coronary heart disease (Hu et al., 2001;Krauss et al., 2000). Siri-Tarino et al. (2015) reported that the effect of SFAs on cardiovascular disease (CVD) risk are modulated by the nutrients that replace them and their food matrices. Therefore the information of fatty acids, cholesterol and fatty acid profile content is required. The content of fat, cholesterol and fatty acid profile can be controlled via the feed source of oil content in the animal feed (Schivone et al., 2010;Wood, et al., 2003, Krejci-treu et al.2010, feed ingredients with high source of omega 3 microalga (Schiavone et al., 2007), differences in eating habits (Krimpen et al., 2011), and the influence of protein (Ahmet et al., 1997). Furthermore, genetics also affects the nutrient content of the Muscovy duck meat (Baeza, 2006, Woloszyn, 2006. The objective of the study is to obtain information on the quality of Muscovy duck meat that was traditionally maintained

Materials and Methods
The Muscovy duck meat obtained from 12 ducks consisted of six males and six females were from six local farm located in Taman Sari Sub-district, Nanggung Sub-district, Cijeruk Subdistrict, Cigombong Sub-district, Tenjolaya Subdistrict,and Pamijahan Sub-district, Bogor City, West Java, Indonesia. Two Muscovy duck samples were taken from each local farm. Male Muscovy ducks aged 8 weeks had a body weight of 913-1,085 grams and female Muscovy ducks around 836-994 grams. Muscovy ducks are slaughtered to obtain samples of breast meat and thigh meat in order to analyze the content of fat, cholesterol and fatty acids.
Six samples of rice bran samples from local farm were analyzed proximate using the AOAC 2005 method. Breast and thigh meat were analyzed the moisture, fat, cholesterol and fatty acid using AOAC 2002. The read used HPLC to cholesterol analyzed and GC to fatty acid analyzed.
In this research, the content of SFA, MUFA, are calculated from the fatty acid composition in breast and thigh meat.
The research data were analyzed using Ttest to get the real difference between the average treatments. The variables measured: (1) Live weight, carcass weight, also the weight and percentage of breast meat and thigh meat, and (2) The content of fat, cholesterol, and fatty acid profile of breast meat and thigh meat.

Feeding
Each farmer generally have Muscovy ducks around 8 weeks old, while adult Muscovy ducks are only owned at most 1 to 2 ducks per farmer. Muscovy ducks which are raised traditionally (semi-intensive) by people in six sub-districts are fed rice bran twice a day in the morning and afternoon, then freed around house yard and needs to be put back inside in the afternoon. Usually the rice bran combined with rice from household waste add water before fed to Muscovy duck. The results of the proximate analysis of rice bran from each farmer are on Table 1. The quality of rice bran was given to Muscovy duck varied greatly. This condition is influenced by the purchasing power of farmer and availability of rice bran. Good quality rice bran has higher price. Based on Table 4, the farmers used rice bran with protein content of 9-11% and crude fiber content around 11-17%. When compared with national standards (SNI), the rice bran used by the farmers were considered grade 2 and grade 3.

Carcass, breast meat and thigh meat weight
Muscovy ducks live weight in the study ranged around 913-1,085 grams for males and 836-994 grams for female Muscovy duck. Based on the interviews with the farmer, the Muscovy ducks in this study were aged 8 weeks old.
Muscovy duck carcass percentage of males and females were relatively the same but the weight percentage of breast meat was higher than the thigh meat. Tugiyanti et al. (2013) stated that native Indonesian Muscovy duck was given rice bran as much as 98.30 % and other feed 1.70 % resulted in the percentage of carcasses was 63.04% The percentage resulted of this study were lower than the results obtained by Farhat et al. (1997), which is 70% for Muscovy duck aged 11 weeks. Male Muscovy ducks have higher breast and thigh meat percentage than female Muscovy duck. It is according to Triyantini et al. (1997), the weight percentage of Muscovy duck breast was higher than the weight of the thigh (26.21% vs. 23.86%).
In addition, the breast meat was higher than thigh meat (15.07% vs. 13.97%) for Muscovy duck age 12 Sunday. Schavioneet al. (2007) stated that Muscovy duck which is intensively raised produce male breast meat weight percentage higher than the female Muscovy ducks aged 64 days (21.27% vs. 20.88%). Ogah (2009) stated that Muscovy duck males have larger body size and is heavier than the female Muscovy duck. As a food source of meat it is better to use a male Muscovy ducks in accordance with Yakubu (2011), in which the male Muscovy ducks are sold to generate income and the female Muscovy ducks are for breeding. The percentage of carcass weight, breast weights and thigh weight were higher in male Muscovy duck than that in the females because male had body weight, body length, body height greater than female (Ogah, 2009).
The variability in growth rate and body weight between male and female of the species is described as sexual dimorphism. Sexual dimorphism in growth performance of male age  (Etuk, 2006). Male Muscovy duck have the ability to consume higher feed, and produced in increased body weight and feed conversion ration more male than female (Suwarta, 2013). The percentage of carcass weight, breast weights and thigh weight were higher in male Muscovy duck than females in this study because male Muscovy duck have body weight, body length and body height greater than female (Ogah, 2009). Sexual dimorphism in growth performance of male age 8 weeks have greater value than that of the female (Etuk, 2006). The variability in growth rate and body weight between male and female of the species is described as sexual dimorphism (Raji et al, 2009). Male Muscovy duck has the ability to consume more feed and resulted in higher body weight gain and feed conversion higher than that of the female (Suwarta, 2013).

Fat, cholesterol, and fatty acid content of muscovy duck meat
Muscovy ducks raised traditionally local farm in Bogor City were fed with low nutritional content and high fiber content feed. High crude fiber content in the feed was derived from used rice bran. Aside from the feed given by the farmer, Muscovy duck also got feed when freed in backyard that could not be detected during the study. According to Setioko (1997), reared duck at backyard had various nutritional content of the crop, the feed material mainly rice, snails, insects, leaves, and also other unknown materials. If Muscovy duck were backyard they will possible most likely fed leaves, insects and other household waste (such as vegetable waste), etc. Fat, cholesterol and fatty acid content of Muscovy duck meat raised traditionally can be seen on Table 3 and the fatty acid profile on tables 4 and 5, and T-test of average fatty acid in breast and thigh on Table  6. The information is expected to increase the demand of duck meat as a food source.
The content of fat and cholesterol of Muscovy duck breast meat varied greatly because the study results were influenced by the source of feed ingredients that were fed each day. Breast meat has lower fat content (P<0.05) and higher cholesterol content (P<0.05) than thigh meat in accordance with Triyantini et al. (1997) the fat content of breast meat was 0.5% and the thigh meat was 1.72% in a Muscovy duck aged 12 weeks old obtained from the traditional market in Karawang Area, West Java. Damayanti (2006) stated that cholesterol content in breast meat lower than thigh meat. Woloszym et al. (2006), reported that cholesterol in breast meat Muscovy duck lower than Pekin duck and crossbreed. The nutritional feed ingredient was manly factor influenced nutritional meat content as fat, cholesterol, and fatty acid of meat beside age, genetic, and habit of Muscovy duck. Older ducks generally have higher fat content (Tiyantini et al, 1997;Damayanti, 2006, Woloszym et al., 2006Krimpen et al., 2011;Baeza, 2006). Thigh meat had a higher fat content (P<0.05) than breast meat because it has a high red meat fiber compared to breast meat with white fibers. Meat which mostly consists of red fibers has a lower protein content and higher fat content than the meat that is composed of mostly white fibers (Soeparno, 2005). Besides, thigh meat has a higher activity than the breast meat which requires high energy.
The fatty acid profile of breast meat and thigh meat varied in this study from six local farmers (Table 4 and 5) because of different quality and quantity of rice bran and other materials that Muscovy ducks consumed while in the backyard. The profile of fatty acid showed that SFA was lower than MUFA and PUFA in breast or thigh meat. The highest MUFA compared to SFA and PUFA were similar to study by Baeza (2006) and Aronal et al. (2012).  et al., 1990). It was the reason of lower linoleic and r-linolenic acid this study. Furthermore, the profile of fatty acids in different parts of the breast and thigh is due to the difference in the percentage of red meat fibers and white meat fibers. White meat fibers (pork) generally contain a percentage of phospholipids and PUFA inferior to red meat fibers (meat of ruminants) (Wood, et al., 2003). The fatty acid profile is also influenced by the fat content of meat, meat tenderness (tenderness), and meat juiciness (Wood et al., 2003). According Krejici-treuet al. (2010) some plant oils affect the fatty acid composition of breast meat and thigh meat broiler.

Conclusions
Muscovy duck that were kept traditionally and provided with rice bran as the main feed had various amount of fat, cholesterol and fatty acid contents in breast meat and thigh meat.
Breast meat had higher ˜3 fatty acid EPA than thigh meat but similar DHA. dZ •šµ Ç Z ˜ 6:˜ ï OE š]} OE vP from 6.50 to 24.14 in breast meat and 8.94 to 31.64 in thigh meat. Breast meat had lower concentration of cholesterol than that of thigh meat