Study on Novel Feeding Systems Using Coconut Co-Products in Swine in the Philippines

The swine and coconut productions are two important agricultural industries in the

Philippines. Pig is the top commodity among the livestock and poultry industries, of which 65% of the pigs are kept by smallhold pig raisers. It is the second most important commodity next to rice because it plays a major role in ensuring the country's food security by providing about 60% of the total animal meat consumption of Filipinos. On the other hand, the Philippines is known to be the top producer of coconut and coconut-based products and co-products in the world. The total area planted to coconut in 2015 was 3.52 million hectares, which is about 26% of the total agricultural land covering 68 out of 81 provinces of the Philippines. Coconut is one of the top 5 commodities in the crop sector and coconut oil remained as the top agricultural export commodity in the Philippines, which accounts for 25% of the total agriculture exports. Together, the pig and coconut farming provide food and livelihood to many Filipinos and greatly contribute to the country's agricultural economy. Clearly, the importance of both pig and coconut industries to the Filipinos cannot be ignored.

Despite being dynamic and technologically advanced, the pig production in the Philippines is still confronted with problems on low sow productivity and production inefficiency brought by high cost of feed. The cost of feed accounts for about 70% of the total cost in animal production. Currently, because of the increasing cost of traditional ingredients (e.g. corn, soybean meal [SBM], wheat, fish meal etc.), the importance and use of agricultural co- products as feedstuff for swine has increased. Thus, co-products of the coconut industry become more important to be used in animal feed. The Philippines, as the top producer of coconut, also produced large volumes of coconut co-products (CCP) which are being used as feed for pigs. Majority of these CCP include copra meal (CM) or copra expellers and white copra (WC), which are mainly used as ingredient in making animal feeds. In 2015, the Philippines topped the production of CM with 720 thousand metric tons of which about 44% were exported mainly to South Korea, Vietnam, and India. The CM is considered as the largest locally available protein feed material in many tropical countries including the Philippines. It is believed to contain high energy value because of its residual oil content. Thus, it is considered as an economical and valuable local feed for pigs that can be used to partially replace costly imported feed ingredients such as SBM. The WC is a co-product of virgin coconut oil (VCO) production. WC is also called coconut residue from VCO. The VCO is the natural oil obtained from fresh, mature kernel of the coconut by mechanical extraction. In the Philippines, the meal or residue were reported to contain a lot of oil with about 35-48% fat content. The residues or WC are used as feeds or processed in high-value products. The use of WC as feed ingredient for pigs is becoming more popular. The protein enriched copra meal (PECM) is another co-product of the coconut industry. PECM is produced by subjecting raw CM in a solid-state fermentation process, using Aspergillus niger to increase its protein content. The crude protein (CP) of PECM ranges from 35% to 38% on a dry matter (DM) basis. Because PECM is a relatively new feedstuff, its feeding value needs to be established.

Despite being available in the Philippines, reliable data on nutrient compositions and feeding values of locally produced CCP in swine are very limited. This lack of data may lead to the use of inaccurate nutrient values for CCP. Such situation will lead to inaccurate feed formulation if CCP is used in the mixed feed. This may affect the production efficiency of pigs. Feeding experiments and laboratory analysis, as well as use of highly specialized equipment are needed to generate data but are expensive. This study aims to determine the nutritive value, and to develop prediction models to estimate the nutrient value of CCP to effectively utilize in swine diets. In this study, the physical characteristic such as color was used to develop tools such as prediction models to estimate the nutritive value in CCP. A special equipment called colorimeter was used to quantify the color. The principle in measuring instrumental color in CCP lies behind the fact that varying degrees of heat treatment are applied to CCP during its production and the process results to differences in the physical color and nutrient composition in CCP. However, reports showed that excessive heat treatment may lead to the Maillard reactions, a process that results to the destruction of amino acids and formation of the Maillard reaction products that are biologically unavailable.

Chapter 2 discusses the prediction of amino acid content and gross energy in different co- products of coconut (Cocos nucifera L.) processing using chemical composition. Samples were collected from different sources not only to establish the nutrient composition and physical characteristics (including instrumental color) of CCP but also to develop equations to estimate nutrient composition in CCP. The result showed that wide variation in the chemical compositions was observed in 28 CCP, particularly in CP, ether extract (EE), crude fiber (CF), starch, and acid detergent lignin (ADL), Ca, P and aflatoxin. Moreover, wide variation was observed in particle size, bulk density and instrumental color in CCP. This suggests that the differences in processing methods and source influenced the chemical compositions and physical characteristics in CCP. Such variations in chemical composition may lead to possibility of using inaccurate nutrient values of CCP in making feeds, which may affect the growth of pigs. Prediction models were successfully developed to estimate the total indispensable amino acids and gross energy (GE) in CCP. Specifically, prediction models were developed to estimate most of the indispensable amino acids (leucine, threonine, valine, methionine, isoleucine and phenylalanine) using the total CP as predictor, and to estimate the concentration of GE in CCP using EE as predictor. The instrumental color (L*, a*, and b* values) was found useful to predict the concentrations of all indispensable amino acids (arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, tryptophan, threonine, and valine) and the GE content in CCP.

Chapter 3 discusses the concentration of digestible, metabolizable and net energy in CCP fed to growing pigs. An energy balance experiment using 22 growing pigs housed in a metabolism cage was conducted to determine the concentration of digestible energy (DE), metabolizable energy (ME) and net energy (NE), and to develop prediction equations for DE and ME in CCP fed to growing pigs. The CCP used were CM, PECM and WC, which were obtained from different sources in the Philippines. A total collection of feces and urine method using marker-to-marker approach as described by Adeola (2001) was used in the experiment. The samples of CCP, diets, feces and urine were collected and analyzed in the laboratory. The DE and ME concentrations of CCP diets and ingredients were calculated. The NE of diets and ingredients were estimated using published prediction equation. The DE, ME, and NE concentrations differed among CCP and ranged from 1,843 to 3,284, 1,666 to 3,211, and 1,008 to 2 ,352 kcal/kg DM, respectively. This may be due to differences in the residual oil and fiber content observed in CCP samples. Moreover, the differences in the processing method and source may influenced the digestibility of energy in CCP. A positive correlation was observed between the DE and ME and acid detergent fiber (ADF) using 8 CCP samples (excluding WC samples). The DE and ME, NE concentrations differ among CCP sources fed to growing pigs. Moreover, DE and ME values in CCP can be predicted using ADF as independent variable. Lastly, instrumental color was not useful to estimate the digestibility of DE and ME in CCP fed to growing pigs.

Chapter 4 discusses the standardized total tract digestibility (STTD) of phosphorus (P) and calcium (Ca) in CCP fed to growing pigs. A feeding experiment using 22 growing pigs was conducted to determine the apparent total tract digestibility (ATTD) and STTD of P and Ca in CCP fed to growing pigs, and to develop prediction equations to estimate ATTD and STTD of P and Ca. The CCP used were CM, PECM and WC, which were obtained from different sources in the Philippines. The samples of CCP, diets and feces were collected and analyzed in the laboratory. The digestibility of P and Ca in CCP were calculated. The ATTD and STTD of P and Ca among CCP sources were not significantly different when fed to growing pigs. This suggests that the digestibility of P and Ca values in CCP are not influenced by the source and processing method used in the production of CCP. The standard total tract digestible P and apparent total tract digestibility Ca in CCP may be best predicted using total P and Ca as independent variables, respectively. However, it was found that instrumental color cannot be used to estimate the digestibility of P and Ca in CCP fed to growing pigs.

Chapter 5 discusses the standardized ileal digestibility (SID) of amino acids in CCP fed to growing pigs. A feeding experiment using 6 pigs (surgically equipped with T-cannula in the distal ileum) was conducted to determine the apparent ileal digestibility (AID) and SID of amino acids in CCP and SBM fed to growing pigs and to develop equations to estimate SID of amino acids in CCP. The CCP used were: 1) CM, 2) WC, 3) oven-dried CM (ODCM, oven-dried at 150°C for 30 min) and 4) PECM which were obtained from different sources in the Philippines. The ileal digesta of pigs were collected, freeze dried and analyzed for CP and amino acid contents. The AID and SID of most amino acids were not significantly different among pigs fed that were diets with different CCP sources. The concentrations of standardized ileal digestible CP and amino acids in CCP were less than SBM. This suggests that the variation in CP and amino acids among CCP sources were not enough to make significant differences. The standardized ileal digestible arginine, glutamic acid, and tyrosine in CCP were negatively correlated with CP. The standardized ileal digestible lysine and proline were negatively correlated with a* value. The lower standardized ileal digestible lysine in ODCM is most likely due to heat damage (oven-drying at 150°C for 30 min) as a result of the Maillard reaction. Moreover, CP and a* value can be used as independent variable to estimate standardized ileal digestible arginine and lysine, respectively, in CCP fed to growing pigs. Lastly, instrumental color can be used to estimate the standardized ileal digestible lysine in CCP fed to growing pigs.

In conclusion, the present study has successfully established reliable data on the chemical composition and physical characteristics, determined the digestibility values of energy (DE, ME, and NE), P and Ca (STTD of P and ATTD of Ca), and the digestibility of amino acids (SID of amino acids) in locally produced CCP. Moreover, this study has developed prediction equations to estimate nutrient composition and feeding values in CCP. Lastly, instrumental color was found useful to estimate the GE content, the total arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, tryptophan, threonine and valine, and the standardized ileal digestible lysine in CCP fed to growing pigs using the prediction models developed. The established nutrient values and the prediction models developed for CCP in this study are expected to maximize the utilization of CCP as an alternative feedstuff in swine.