3RD INTERNATIONAL CONGRESS ON TECHNOLOGY - ENGINEERING & SCIENCE - Kuala Lumpur - Malaysia (2017-02-09)

Effect Of Feeding Graded Level Of Energy And Crude Fiber From Sawdust In Diets On Carcass Quality Of Broilers

EFFECT OF FEEDING GRADED LEVEL OF ENERGY AND CRUDE FIBER FROM SAWDUST IN DIETS ON CARCASS QUALITY OF BROILERS Jet Saartje Mandey1*, Youdhie H.S. Kowel1, Mursye N. Regar1, Jein Rinny Leke2 1Animal Nutrition Department, Animal Husbandry Faculty, Sam Ratulangi University Manado, Indonesia 2Animal Production Department, Animal Husbandry Faculty, Sam Ratulangi University Manado, Indonesia *Corresponding Author: Phone: +62-85256960744; E-mail: jetsm_fapet@yahoo.co.id Abstract: Dietary fiber can influence health of the animal through several potential mechanisms. Structure and function of the gut is directly influenced by fiber in the diet, and energy demand of the gut is likely due to the high cell turnover rate observed in the epithelial lining of the gut. This study was conducted to investigate the effect of feeding combination of graded level of energy and crude fiber diets with normal level of crude protein on carcass quality of broilers. A total of 120 D.O.C of broilers were used for the research. The experiment utilized a completely randomized design in 2 x 3 factorial arrangement of treatments consisting of two dietary concentrations of energy (lower and higher) and three dietary concentrations of crude fiber. Each treatment was subdivided into 4 replications (5 birds each) fed from 1 to 35 d. The birds were housed in battery cages in an environmentally controlled room with ad libitum access to feed and water. During which, feed intake, carcass yield, abdominal fat, blood LDL-cholesterol and HDL-cholesterol were measured. Birds were weighed and slaughtered by serving of the artery in a single cut and bled. After slaughter, carcass weight measured on the chilled carcass after removal of feather, head, lungs, gastrointestinal tractus, liver, kidney, abdominal fat, dissected and collected. Carcass calculated as the percentage of fasted live body weight. All experimental data were subjected to the analysis of variance test (ANOVA) followed by least significant difference test (LSD). Results showed that the daily feed intake was significantly affected by levels of energy and crude fiber, and were highly significant affected to carcass and abdominal fat percentage, and blood LDL-cholesterol. The interaction of levels of energy and crude fiber was not affected to the value of blood HDL-cholesterol. The diet with 3100 Kcal/kg and 11% crude fiber was significantly decreased feed intake, abdominal fat percentage, and blood LDL-cholesterol, but were no affected to final body weight and the value of blood HDL-cholesterol and kept the good value of carcass percentage. It can be concluded that ME could be acceptable up to 3100 Kcal/kg levels combined with 11% crude fiber in broiler diets. Key words: Broiler, Carcass, Crude fiber, Dietary energy, Sawdust. Introduction: Poultry feeding is an important factor in poultry production. The improvement of poultry production is highly depend on synergy between science and practice. By use of modern technology and nutrition knowledge, production of fattening chicken highly increased in the whole world in last 30 years (Steiner, 2008). Dietary fiber is traditionally considered a diet diluent and often, an anti-nutritional factor (Rougiere, et al., 2010). However, moderate amounts of fiber may promote organ development, enzyme production, and nutrient digestibility in poultry. Fibrous feed ingredients have been used in diets of ruminant animals; however, in the developed world has encouraged researchers to seek a greater understanding of the role of fibrous feedstuffs in diets for non ruminant livestock (Abo Omar, 2005). Use of high dietary fiber feed ingredients in poultry diet has generally been discouraged due to the negative effects exerted on nutrient utilization and performance such as their documented depression of diet digestibility poultry, and decrease in body weight gain and feed conversion (Kras, et al., 2013). However, some types of fiber and fiber sources do not exert such negative effects on nutrient digestibility. Dietary fiber can have positive effects on gut health, welfare, and reproductive performance of pigs, and it is possible for poultry (Trowell, et al., 1976). Some of these effects result from better gizzard function, with an increase in the gastroduodenal reflux that promotes the contact between nutrients and digestive enzymes (Mateos, et al., 2012; Jimenez-Moreno, et al., 2009). Fiber in feed ingredients may affect cecal microbial population and nutrient digestibility. Interactions of these effects can affect bird performance. Thus, nutritionists are faced with a challenge of formulating diets with the available feed ingredients, but also having to mitigate the resulting diet effects to achieve optimum bird production. Bach Knudsen (2001) stated that it is important to note that fiber in monogastric diets is mainly utilized in the hind gut (i.e. ceca, rectum and the colon). Feeding animals diets high in dietary fiber, particularly soluble fiber alters the rate of fecal passage, microbiota, metabolites, and efficacy of digestion. Insoluble fiber in monogastric diets has for long been considered as diluent of nutrients (Edwards, 1995). The little or no degradation of insoluble fiber in chickens results in increased bulk of digesta in the intestinal tract that eventually leads to fast digesta passage through the gastrointestinal tract, unless the animal has a large digestive system capacity. This makes its effect on microbial population quite insignificant (Langhout, 1998). Moreover, since diets high in insoluble fiber contain low energy, birds tend to increase feed consumption as a way to compensate for the reduced nutrient concentration in feed (Hill and Dansky, 1954). The most widely accepted definition of fiber states that fiber is the sum of lignin and polysaccharides that are not digested by endogenous secretions of the digestive tract (Trowell, et al., 1976). Determination of the required amount of energy and protein in feedstuff is also probably the most important decision to be made when it comes to feed formulation for broiler (Steiner, 2008). Hence formulation of animal feed must take into consideration the nutrient density with energy as the prime factor of the particular feed to facilitate production objectives. The performance of broiler chicks were evaluated by Onwudike (1983) that recommended 22% crude protein and 2900 Kcal/kg metabolizable energy. Increasing dietary energy level will result in increase weight gain and also improvement of feed conversion (Araujo, et al., 2005; Albuquerque, et al., 2003). Attention is, therefore, being focused on cheap but suitable alternative feedstuffs, especially crop residues and industrial by products, to sustain livestock industry (Alhassan, 1985). Many forms of residues are produced from wood processing plants. For instance, sawmill residue consists of sawdust, planer shavings, lumber edge and end trim, slabs cut from the outer portions of the log, and shredded bark. The shredded bark, sawdust, and shavings frequently have no markets, but these residues are used increasingly as fuel by the forest products industry. Most untreated woods are quite indigestible. Millett, et al. (1970) determined the relative digestibility of 27 species of trees. All of the hardwood species examined showed some degree of digestibility, ranging from a low of 2 percent to a high of 37 percent. The sawdust up to 80 g kg-1 level of inclusion in broiler diets did not have any detrimental effect on weight gain. Since sawdust is abundant and available throughout the year in many developing country, the utilization of sawdust will reduce the cost of production (Oke and Oke, 2007). National data of Indonesia according to BPS 2006, production of sawdust from furniture industry were 679.247 m3 in 600 kg/m3 density, equal to 407,508.2 ton (Danar dan Debi, 2010). Generally, whole-tree or tree residues are not considered dangerous to the health of livestock. It is essential, however, that diets containing wood residues be properly balanced for all of the essential nutrients. Wood residues must be considered primarily as energy sources. They contain only small amounts, or are nearly devoid, of many essential nutrients. Thus, animals consuming diets containing large amounts of wood residues will encounter ill health if the diets are improperly balanced. Before it can be recommended as a feedstuff, wood residue should be chemically characterized (Committee on Animal Nutrition Board on Agriculture, N.R.C., 1983). Agri-food wastes, in its majority, are comprised of lignocellulosic materials. Aspen sawdust has been shown effective as a partial forage substitute in a high-grain dairy diet (Satter, et al., 1970). Cows fed 2.3 kg hay and about 17 kg of a pelleted diet containing one-third aspen sawdust maintained normal milk fat. Cows receiving a similar diet but without sawdust produced milk with 50 percent as much fat. Oak sawdust is essentially indigestible, and has been used in several growth or feedlot trials as a roughage substitute (El-Sabban, et al., 1971). Inclusion of 5 to 15 percent oak sawdust in the diet has generally supported animal performance equal to the other experimental groups being tested. Similar conclusions were reached when pine sawdust was used as a roughage substitute in beef finishing diets (Slyter and Kamstra, 1974). The physiological and practical implications of the link between crude fiber and energy intake under iso-protein must then be considered when the dietary requirements for either nutrient is assessed. Moreover, there is a lack of sufficient information about the effect of dietary energy density and crude fiber level on the performance of broiler chickens. Therefore, the aim of this investigation was to study the effect of feeding high and low dietary energy with high and low crude fiber levels on carcass quality of broiler chickens. Materials and Methods: Birds, Diets and Experimental Design A total of 120 D.O.C of broilers were used for the research. The experiment utilized a completely randomized design in 2 x 3 factorial arrangement of treatments consisting of two dietary concentrations of energy (lower and higher) and three dietary concentrations of crude fiber. Each treatment was subdivided into 4 replications (5 birds each) fed from 1 to 35 d. The birds were housed in battery cages in an environmentally controlled room. Feed and water were given ad libitum. During the experimental period (1 to 35 days) chickens were fed with diets of compound mixtures, as follow, the recipes of compound feed used had different levels of energy and fiber under iso-protein. The crude fiber source of feedstuffs especially from sawdust and then were mixed with other crude fiber sources. The values for different levels of crude fiber and metabolizable energy were showed in Table 1. The performance characteristics were feed intake, final body weight, carcass weight, abdominal fat, blood HDL-cholesterol and LDL-cholesterol. These were measured during the finisher phases. During which, feed intake and body weight were measured, and, at the end of the experimental, one representative bird from each pen was conventionally sacrified by cervical dislocation technique, as described in the Report of the AVMA Panel on Euthanasia (AVMA, 2001) and its carcass parameters (ready to cook) including dressing percentage and abdominal fat were determined. Carcass characteristic was weighted after removal of feather, head, lungs, gastrointestinal tracts, liver, kidney, abdominal fat, dissected and collected. The eviscerated weight was measured to calculate the dressing percentage as the percent of dressed carcass weight to live weight of the bird. Table 1. Chemical Composition of the Diets Feedstuffs (%) Treatments A1 A2 B1 B2 B3 B1 B2 B3 Yellow corn 47.00 44.00 34.75 52.50 45.00 38.50 Rice bran 15.00 14.50 14.00 9.00 9.00 8.00 Soybean 10.00 11.50 12.50 15.00 15.00 15.00 Coconut cake 15.00 12.00 14.00 8.00 8.00 8.00 Fish meal 12.00 13.00 13.00 12.00 13.00 14.25 Sawdust 0.25 3.50 7.25 1.00 5.00 9.00 Coconut oil 0.25 1.00 4.00 2.00 4.50 6.75 Top Mix 0.50 0.50 0.50 0.50 0.50 0.50 Total 100 100 100 100 100 100 Chemical Composition: Protein (%) 20.11 20.38 20.34 20.30 20.29 20.40 Crude Fiber (%) 5.08 7.94 11.05 5.00 8.07 11.05 Fat (%) 5.51 6.09 8.71 6.58 8.89 10.89 Ca (%) 0.75 0.83 0.86 0.75 0.91 0.93 P (%) 0.86 0.86 0.77 0.78 0.78 0.79 ME (Kcal/kg) 2801 2796 2803 3107 3104 3103 Notes: A = energy levels; B = crude fiber levels Abdominal fat pad (including fat surrounding gizzard, bursa of fabricius, cloaca & adjacent muscles) was removed and weighed individually for 4 chicks per treatment. Blood samples were collected from the wing vein of 5 chicks, in each group, at the end of the experiment (35 days) to measure some cholesterol analysis. Statistical Analysis Data were subjected with analysis of variance of completely randomized design in 2 x 3 factorial arrangement, and it was continued to least significant difference test (LSD) (Steel and Torrie, 1994) at a probably level of 5% when the treatment indicated significant effect. The IBM SPSS Statistics 22 software was used for the statistical processing of data. Results: The effects of different metabolizable energy and fiber levels in diets on carcass quality of broiler chickens were showed in Table 2. Results showed that the daily feed intake was significantly affected by levels of energy and crude fiber, and were highly significant affected to carcass and abdominal fat percentage, and blood LDL-cholesterol. The interaction of levels of energy and crude fiber was not affected to final body weight and the value of blood HDL-cholesterol. The diet with 3100 Kcal/kg and 11% crude fiber was significantly decreased feed intake, abdominal fat percentage, and blood LDL-cholesterol, but were no affected to final body weight and the value of blood HDL-cholesterol and kept the good value of carcass percentage. Table 2. Effect of the Treatment Diets on Carcass Quality Variables Energy Level (A) Crude Fiber Level (B) p Value AxB B1 (5%) B2 (8%) B3 (11%) Feed Intake (g) b-1 d-1 A1 (2800 Kcal/kg) 127.1ab 136.1c 135.4c .001 A2 (3100 Kcal/kg) 124.6a 129.5b 124.9a Final Body Weight (g) A1 (2800 Kcal/kg) 1786 1797 1656 .673 A2 (3100 Kcal/kg) 1767 1766 1779 Carcass (%) A1 (2800 Kcal/kg) 73.28b 72.47b 70.46a .004 A2 (3100 Kcal/kg) 72.92b 72.93b 72.62b Abdominal Fat (%) A1 (2800 Kcal/kg) 2.02b 1.93ab 1.69a .006 A2 (3100 Kcal/kg) 2.49c 1.79a 1.64a HDL-Cholesterol (mg/dl) A1 (2800 Kcal/kg) 100.2 98.3 101.9 .884 A2 (3100 Kcal/kg) 99.9 97.3 103.8 LDL-Cholesterol (mg/dl) A1 (2800 Kcal/kg) 100.8b 108.8c 104.0b .025 A2 (3100 Kcal/kg) 106.4b 102.8b 92.0a The result of feed intake in this study was not in line in that Tooci, et al. (2009) reported, treatments dietary dilution of energy were not show significantly difference on feed intake. Scott, et al. (1982) announced that animals such as poultry eat feedstuff with the aim of energy requirements. Therefore, feed intake should be increased upon reduction of dietary energy, aimed at meeting energy requirement. The results of this study showed that percentage of abdominal fat was significantly decreased although dietary energy level increase, and that is due to high crude fiber level. Waldroup, et al. (1990) announced that dietary energy level affects abdominal fat weight. The data announced on abdominal fat as compared with body weight, they explained abdominal fat increase in all cases is due to dietary energy level increase (Maiorka, et al., 2005). Discussion: The voluntary feed intake of birds have been established to be a function of dietary fiber characteristics. Soluble fiber is known to increase viscosity in the small intestine (Choct et al., 1996), and subsequently inhibits digestion and absorption. The rate of digesta passage is reduced, feed intake is decreased, creating favorable conditions for proliferation of microbes in the intestine (Choct, et al., 1996; Langhout, 1998). Since diets high in insoluble fiber contain low energy, birds tend to increase feed consumption as a way to compensate for the reduced nutrient concentration in feed (Hill and Dansky, 1954). Feed ingredients high in insoluble fiber cause an increase in the bulk of the digesta that eventually leads to fast digesta passage through the gastrointestinal tracts, unless the animal has a large digestive system capacity. This effect has been reported to improve digestibility (Krogdahl, 1986). There are suggestions that fiber decreases nutrient digestion because it encapsulates nutrients into the plant cell causing a reduction in the activity of digestive enzymes. Insoluble fiber has been reported to have some beneficial effects. Some experiments have shown that as long as insoluble fiber is included in poultry diets at moderate concentrations, performance of birds will not be affected despite the fact that the nutrient concentration of the diet is reduced (Hetland, et al, 2003; Hetland, et al., 2004). However, the mechanism of formulating diets with moderate levels of insoluble fiber is not well known. Fiber reduces density of diets (Savory and Gentle, 1976) and makes birds to consume more feed in order to acquire enough energy for metabolic activities (Faniyi and Ologhobo, 1999). Sainsbury (1980) stated that young and old birds can tolerate dietary fiber contents of 13 and 15% respectively for efficient functioning of their alimentary tract. Daily live weight gain significantly increased as the level of sawdust increased up to 80 g kg-1 and declined at 100 g kg-1 inclusion rate (Oke and Oke, 2007). The performance of broiler chicks were evaluated by Olomu and Offiong (1980) and reported that 23% crude protein (CP) with either 2800 or 3000 kcal/kg metabolizable energy (M.E.) was adequate as the requirement for starter broiler birds while Ojewola and Longe (1999) reported that the feeding of 27% crude protein (which is considered high) in the broiler chicks’. Saleh (2004) studied energy influence on breeding characteristics of broiler chicks and determined that body weight increased significantly on 21st, 42nd, and 49th day of breeding in case of chicks bred up to the energy levels of 13.7% MJ/kg ME and 22.32% of crude proteins. Some of the carcass compositions of the broiler chicken were affected by the different dietary levels of the energy and fiber. Fat partition among the major depots, included excessive amount of non carcass fat at market age has become a commercial problem to all segments of meat industry, as it may influence yields, waste management, waste of dietary energy and consumers' acceptability i.e. increasing concern with diet health issues (Leenstra, et al., 1986). The body fat deposition significantly increased in birds fed high and normal energy inclusion in the diets resulting into a high calorie: protein ratio which agrees with the report of Swenen, et al. (2006). The most abdominal fat (2.29% average of live weight for male and females) was produced by broilers offered a diet calculated to contain 3325 ME Kcal/kg. The least amount of abdominal fat (1.92% average of live weight for male and females) was produced by broilers offered diets calculated to contain 3100 and 3175 metabolizable energy (ME) Kcal/kg (Deaton, et al., 1983). 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Jet Saartje Mandey, Youdhie H.S. Kowel, Mursye N. Regar, Jein Rinny Leke