Sử dụng hiệu quả khẩu phần nguồn thức ăn địa phương cho giống lợn bản địa moo lath, CHDCND lào

HUE UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY BOUNLERTH SIVILAI THE UTILIZATION OF DIETARY LOCAL FEED RESOURCES FOR MOO LATH PIG IN LAOS DOCTOR OF PHILOSOPHY IN AGRICULTURE HUE, 2019 HUE UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY BOUNLERTH SIVILAI THE UTILIZATION OF DIETARY LOCAL FEED RESOURCES FOR MOO LATH PIG IN LAOS SPECIALIZATION: ANIMAL SCIENCE CODE: 9620105 DOCTOR OF PHILOSOPHY IN AGRICULTURE SUPERVISORS: ASSOC.PROF.DR NGUYEN QUANG LINH ASSOC.PROF DR DU THANH HANG HUE - 2019 DECLARATION I declared that this thesis is my original research works It is a scientific research which overall data presented in this thesis are contributed truly and righteously The research works was done under the guidance of Professors in Hue University and collaborative professional researchers All acceptation is evidently indicated to the best of immense knowledge that they have been published in Journal of Livestock Research for Rural Development (LRRD) Hue, April 2019 Bounlerth SIVILAI ACKNOWLEDGEMENT This thesis describes research on the improving and utilization of foragebased diets for Moo Lath pigs in Laos, I wish to thank Mekong Basin Animal Research Network (Sida/MEKARN II) project and University of Agriculture and Forestry, Hue University for financial support of experiments and the course works in Vietnam This thesis based on the efforts of many people In the first place, I would like to thank all those persons who contributed to obtaining the data and the texts of the various chapters Without their help this thesis would never been written Especially, I would like to express my sincere thanks to Professor Nguyen Quang Linh, Professor Thomas Reg Preston, who always open the gates to scientific research I am also grateful for their supervision and guidance of my research I would like to express my heartfelt thanks to Professor Du Thanh Hang, who supervised the data analysis It would be nice to thank for all of lecturers and researchers in Hue with hospitality while my staying in Hue city I am grateful to Dr Lampheuy Kaensombath and professor R.A Leng for their contributions and helping My sincere thanks also goes to Dr Kieu Borin, regional coordinator of the Sida/MEKARN II project for any support and make the PhD program possible and Dr Chive Phiny for the budgets for travelling and allowances Dr Vanthong Phengvichit and Dr Daovy Kongmanila the country coordinators for providing the immense suggestion on study condition and financial report as well as accountants in National Agriculture and Forestry Research Institute (NAFRI) for arrangement research funds conveniently Also thank my colleagues, friends and teachers in Department of Livestock and Fishery, Faculty of Agriculture (FAG), National University of Laos for their kindly supports My lovely students and their friends whom helped in field works with forage collecting, experiments and sample preparing analysis Last but not least, I would like to thank my family for all their kind regards, encouragement and love Most of appreciation to my wife Linh Thamavong for her patience, effort working hard and taking care for our family during my studying Special thank to my mother for her support, loving and devotion to my three children during studying time Great thanks to my sister Boakeo Phaisilai and her husband, my younger sister Boasone Sivilai and my uncles’ family for their help in looking my mother, supporting me spiritually throughout studying, writing thesis and my life in generally ABSTRACT The research was objected to investigate the effect of ensiled taro foliage combined with banana pseudo stem as basal diets, using by-product of rice distillers or brewers’ grains, and biochar as feed additive supplemented in the diet of native Moo Lath Lao pig Four experiments were conducted to comprising on the thesis The first experiment (Chapter 2): Four pigs were used in the experiment with 30 kg  2.63 kg LW An experiment was arranged in a 4*4 Latin Square Design with diet levels of ensiled banana pseudo stem of 0, 5, 10 and 15% replacing ensiled taro foliage and soybean meal Apparent digestibility of DM and CP, daily N retention and biological value (BV), all declined linearly as ensiled banana-pseudo stem replaced ensiled taro foliage It is appeared that the BV of the protein in the ensiled taro foliage was superior to combination of ensiled banana pseudo stem and soybean meal In the second experiment (Chapter 3): A small amount of either rice distillers’ by-product (RDB) and brewers’ grain (BG) were added in the ensiled forage-based diet Six female native Moo Lath pigs (29.3  2.3 kg LW), fed a basal diet of ensiled banana pseudo-stem, ensiled Taro foliage and broken rice were allocated to a 3*3 double Latin Square Design Three treatments were BG 4%, RDB 4% or no supplement (CTL) Both supplements improved feed intake, digestibility and N retention, with indications of greater responses in N retention and in the biological value of the protein for the rice distillers’ by-product It is suggested that the beneficial effect of both supplements may have been due to the presence of βglucan, a component of the cell wall of both cereal grains and yeasts, that is shown to have immunological, health-benefiting effects in animal In the third experiment (Chapter 4): The supplements would bring similar benefits during the stage of pregnancy and lactation in Moo Lath gilts Twelve native Moo Lath pig gilts (80.8 ± 3.9 kg LW) were used in the experiment Three dietary treatments in a completely randomized design with replications were: CTL: No supplement; RDB 4% or BG 4% in diet DM basis The pig gilts gained more body weight during gestation, and were heavier at the end of lactation, when their diet was supplemented with 4% BG or 4% RDB The litter sizes from dams supplemented with 4% RDB were heavier at birth, and at weaning, and grew faster than litters from un-supplemented gilts Supplementation of BG4% or RDB 4% appeared to have no effect on piglet mortality at birth or during lactation, nor on live weights of piglets at birth or weaning, and did not affect overall feed DM intake However, DM feed conversion was improved by 60% when the Moo Lath gilts were supplemented with 4% RDB In the fourth experiment (Chapter 5): The study was to evaluate the effect of biochar compare with rice distillers’ by-product fed a forage diet on growing pigs Twenty native Moo Lath pigs (15.8 ± 1.3 kg LW) were housed in individual concrete pens There were four dietary treatments arranged as a completely randomized design The treatments (% in diet DM) were: no additive (CTL), 4% rice distillers’ by-product (RDB), 1% biochar (BIO) and the combination of RDB and BIO (RDB+BIO) The growth rate tended to be better (p=0.089) and feed conversion was improved (p=0.048) for both additives, fed separately or together, when compared with the control diet There were no benefits from combining both additives compared with feeding each one separately Keywords: Local forage, prebiotic, additive feed, indigenous pig, biological value, growing, pregnancy-lactation, piglets DEDICATION To my family with my respectful gratitude: Parents, my wife (with daughter and son), older and younger sisters ແດດ່ຄອບຄຄົວທທດ່ແສນເຄຄົາລຄົບຮຮກຂອງຂຂອຍ: ພພດ່ແມດ່, ພຮນລະຍາ (ພຂອມດຂວຍລລູກສາວ ແລະ ລລູກຊາຍ), ເອອຂອຍ ແລະ ນຂອງສາວ TABLE OF CONTENTS DECLARATION I ACKNOWLEDGEMENT II ABSTRACT III DEDICATION .V TABLE OF CONTENTS VI LIST OF TABLES IX LIST OF FIGURES XI LIST OF ABBRIVIATIONS AND SYMBOLS XIV INTRODUCTION 1 BACKGROUND OF THE STUDY AIMS AND OBJECTIVES OF THE STUDY 2.1 Aims of the thesis 2.2 Objectives of the thesis .4 HYPOTHESES OF THE RESEARCH 4 INNOVATION CONTRIBUTED OF THE DISSERTATION REFERENCE CHAPTER 1: LITERATURE REVIEW 10 1.1 PIG PRODUCTION IN SMALLHOLDER OF LAOS .10 1.1.1 The role of pig production .10 1.1.2 Pig population and consumption 10 1.2 CURRENTLY TYPICAL PIG FARMING IN LAOS 11 1.2.1 Smallholder pig farming 12 1.2.2 Semi-intensive pig production .15 1.2.3 Commercial scale pig production 16 1.3 Feeds and feeding practical management in smallholder pig farms 17 1.3.1 Feeds derived from agricultural by-products 17 1.3.2 Green plant materials as feeds for pigs 18 1.3.3 Feeds derived from leftover materials 18 1.4 CONSTRAINTS AND OPPORTUNITY IN SMALLHOLDER FARMS .18 1.4.1 Main problem in smallholder pig production 18 1.4.2 Opportunity improvement of pig productivity 19 1.5 ALTERNATIVE USE OF LOCAL FEED RESOURCES FOR PIGS 20 1.5.1 Taro foliage (Colocasia esculenta) 20 1.5.2 Banana pseudo stem (Musa spp) by-product 22 1.6 UTILIZATION OF FORAGE-BASED DIET FOR PIGS 23 1.6.1 Taro as protein sources for pigs .23 1.6.2 Effect of taro foliage on apparent digestibility and N retention in pigs 23 1.6.3 Effect of taro foliage on growth performance of pigs 24 1.6.4 Effect of taro foliage replacing by banana pseudo stem in pig diets .25 1.7 GRAIN FERMENTED BYPRODUCTS AS SUPPLEMENT FEED FOR PIGS 27 1.7.1 Rice distillers (Khi-Lao) by-products .27 1.7.2 Brewery grain (Khibeer) by-product 29 1.8 UTILIZATION OF GRAIN FERMENTATION BYPRODUCTS 32 1.8.1 Use of rice distillers’ by-product or brewers’ grains as protein sources 32 1.8.2 Effect of rice distillers’ by-product or brewers’ grains as supplement feeds 33 1.8.3 The use of biochar as a feed additive in animals 33 1.9 NUTRIENT REQUIREMENT OF PIGS .34 1.9.1 Dietary protein requirement 34 1.9.2 Dietary energy requirement 35 REFERENCES .36 CHAPTER 2: EFFECT OF REPLACING ENSILED TARO FOLIAGE (COLOCASIA ESCULENTA) WITH ENSILED BANANA PSEUDO STEM (MUSA SPP) AND SOYBEAN MEAL ON INTAKE, DIGESTIBILITY AND NITROGEN RETENTION IN MOO LATH PIGS 49 CHAPTER 3: A LOW CONCENTRATION OF RICE DISTILLERS’ BYPRODUCT OR OF BREWERS’ GRAINS ON DIGESTIBILITY AND NITROGEN RETENTION IN NATIVE MOO LATH PIGS FED ENSILED BANANA PSEUDO-STEM (MUSA SPP) AND ENSILED TARO FOLIAGE (COLOCASIA ESCULENTA) 58 the Moo Lath pigs agrees with previous results in our laboratory where: (i) 4% (as DM) of rice distillers by-product improved N retention in growing Moo Lath pigs by 36% and the biological value of the nitrogen by 18% (Sivilai and Preston, 2017): and (ii) 4% (as DM) of rice distillers by-product increased the litter weight of weaned pigs from Moo Lath gilts by 67% and the overall feed conversion (feed consumed in pregnancy and lactation/weight of weaned piglets) by 64% (Sivilai et al., 2018) To our knowledge, the feeding of biochar to pigs has not previously been reported The degree of response observed in this experiment with growing pigs (20-23% and 11-14% for growth and feed conversion) is similar to the 15 and 18% improvements in growth and feed conversion reported for biochar fed to cattle (Sengsouly and Preston, 2016) and the 27 and 13% improvements in growth and feed conversion when biochar was fed to goats (Silivong and Preston, 2016) Distillers’ by-products contain the remains of the yeast that produce the alcohol., The cell wall of S cerevisiae contains a scaffold of β-glucans attached to highly glycosylated mannoproteins (Shetty et al., 2006) that can bind numerous compounds, microorganisms or provide habitat for biofilm formation Biochar is relatively inert but also has sites for microorganisms, sorption of chemicals and is known to provide habitat for biofilm formation (Leng, 2017) Therefore, both additives have numerous sites for absorption and binding of compounds and microorganisms and potentially also provide habitat for biofilm attachment Biochar and rice distillers’ by-product each increase pig growth rate and efficiency of feed utilization but the effects were not additive when they were combined It is possible that both additives are controlling or preventing reactions that removed whatever caused the lowered production in their absence It is possible that the feed used in the present study had become contaminated with mould that produces a variety of mycotoxins The silage component although high in moisture, with a low pH can contain moulds on the herbage before and after harvesting and even in the ensiling process before acidification causes the fermentative process to cease Leng (2017) hypothesized that given time the rumen micro biome has an enormous capacity to degrade many phytotoxins and 106 mycotoxins provided a specific habitat is available together with the toxin Similarly, the caecum/colon of the pig may have the same capacity Whilst considerable research needs to be done, the possibility here is that biochar and distillers’ by-products bind toxins from the feed which are either excreted in the faces or degraded by some organisms in the animal’s gut micro biome This concept is supported by the report of Prasai et al (2017) that: “supplementation of feed fed to hens with biochar, zeolite or bentonite improved egg yield and feed conversion ratio, with these additives potentially acting as detoxifiers or inhibiting growth of microbial pathogens, slowing digestion or altering the gut anatomy and micro biota to improve feed conversion ratio” Leng (2017) argued a similar case for the detoxification of mymosine and fluoroacetate in ruminants that had never been exposed to these in their feed The related issue is the extent to which the soil ameliorating properties of biochar will be observed when the excreta of biochar-fed animals is returned to the soil as fertilizer This expectation is conditional on the animals being fully integrated in the farming system Conclusions  In pigs, growth rate tended to be better (p=0.089) and feed conversion was improved (p=0.048) for both additives, fed separately or together, when compared with the control diet The improvements in weight gain were 20.1 and 22.9% for biochar and RDB added separately and 22.9% for the combined  additives For feed conversion the relative degrees of improvement were 10.6, 12.2 and 9.30% There were no benefits from combining both additives compared with  feeding each one separately It is postulated that biochar and distillers’ by-product recommended to bind toxins from the feed which are either excreted in the faces or degraded by some organisms in the animal’s gut microbiome Acknowledgement This research was done by the senior author as part of the requirements for the PhD degree in Animal Science of the University of Agriculture and Forestry, 107 Hue University, Vietnam The authors acknowledge support for this research from the MEKARN II project (Improving Livelihood and Food Security of the people in Lower Mekong Basin through Climate Change Mitigation), financed by Sida and coresearch fund of the National University of Laos Special thanks are given to animal science students (Bounphan Sitthaphone and Saysomphone Kaiyalath) for their assistance in field work and the laboratory during the experiment The Faculty of Agriculture, National University of Laos is acknowledged for providing the facilities to carry out this research REFERENCES AOAC., 1990 Official Methods of Analysis Association of Official Analytical Chemists Washington DC Binh, P.L.T., Preston, T.R., Duong, K.N and Leng, R.A., 2017 A low concentration (4% in diet dry matter) of brewers’ grains improves the growth rate and reduces thiocyanate excretion of cattle fed cassava pulp-urea and “bitter” cassava foliage Livestock Research for Rural Development, 29 (104) http://www.lrrd.org/lrrd 29/5/phuo29104.html Lan, T.T., Preston, T.R and Leng, R.A., 2016 Feeding biochar or charcoal increased the growth rate of striped catfish (Pangasius hypophthalmus) and improved water quality Livestock Research for Rural Development 28 (84) http://www.lrrd.o rg/lrrd28/5/lan28084.html Lehmann, J., 2007 A handful of 144 http://www.css.cornell carbon Nature, 447, 143- edu/faculty/lehmann/publ/Nature %20447,%20143-144,%202007%20Lehmann.pdf Lehmann, J and Joseph, S., 2015 Biochar for environmental management; science, technology and implementation (2nd Edition.) Published by Earthscan UK and USA Leng, R.A., Inthapanya, S and Preston, T.R., 2012 Biochar lowers net methane production from rumen fluid in vitro Livestock Research for Rural Development, 24 (103) http://www.lrrd.org/lrrd24/6/sang24103.htm Leng, R.A., Preston, T.R and Inthapanya, S., 2012 Biochar reduces enteric methane and improves growth and feed conversion in local “Yellow” cattle fed cassava 108 root chips and fresh cassava foliage Livestock Research for Rural Development, 24 (199) http://www.lrrd.org/lrrd24/11/leng24199.htm Leng, R.A., 2017 Biofilm compartmentalisation of the rumen microbiome: modification of fermentation and degradation of dietary toxins Animal Production Science 57 (11), 2188-2203 https://doi.org/10.1071/AN17382 Manh, L.H., Xuan Dung, N.N., Kinh, L.V., Binh, T.C., Thu Hang, B.P and Phuoc, T.V., 2009 Composition and nutritive value of rice distillers’ by-product (hem) for small-holder pig production Livestock Researchfor Rural Development, 21 (224) http://www.lrrd.org/lrrd21/12/manh21224.htm Manivanh, N., Ngoan, L.D and Preston, T.R., 2012 Apparent digestibility and N retention in growing pigs fed rice bran supplemented with different proportions of ensiled Taro foliage (Colocacia esculenta) and rice distillers’ by-product Livestock Research for Rural Development, 24 (67) http://www.lrrd.org/lrrd24/4/noup2406 7.htm Minitab., 2016 Minitab reference Manual release 16 version User’s guide to statistics Minitab Inc USA Orosco, J., Patiđo, F.J., Quintero, M.J and Rodríguez, L., 2018 Residual biomass gasification on a small scale and its thermal utilization for coffee drying Livestock Research for Rural Development, 30 (5) http://www.lrrd.org/lrrd30/1/jair30005.h tml Philavong, S., Preston, T.R and Leng, R.A., 2017 Biochar improves the proteinenrichment of cassaa pulp by yeast fermentation Livestock Research for Rural Development, 29 (241) http://www.lrrd.org/lrrd29/12/somp29241.html Prasai, T.P., Walsh, K.B., Midmore, D.J and Bhattarai, S.P., 2017 Effect of biochar, zeolite and bentonite feed supplements on egg yield and excreta Animal Production Science, 58 (9), 1632 doi.org/10.1071/an16290 Preston, T.R., 2015 The role of biochar in farming systems producing food and energy from biomass In: Geotherapy: Innovative methods of soil fertility restoration In: Carbon sequestration, and reversing CO2 increase (Editor Thomas J Goreau) CRC Press, Tayler and Francis Group, Boca Raton, Florida 109 USA Rodríguez, L and Preston, T.R., 2010 Gasification of fibrous crop residues and live stock production; essential elements in establishing carbon-negative farming systems Livestock Research for Rural Development, 22 (10) http://www.lrrd.org/l rrd22/1/rodr22010.htm Sengsouly, P and Preston, T.R., 2016 Effect of rice-wine distillers’ byproduct and biochar on growth performance and methane emissions in local “Yellow” cattle fed ensiled cassava root, urea, cassava foliage and rice straw Livestock Research for Rural Development, 28 (178) http://www.lrrd.org/lrrd28/10/seng28178.html Shetty, P.H., Hald, B and Jespersen, L., 2006 Surface binding of aflatoxin B1 bySaccharomyces cerevisiae strains with potential decontaminating abilities in indigenous fermented food International Journal Food Science Microbiology, 113 (1), 41-46 Silivong, P and Preston, T.R., 2016 Supplements of water spinach (Ipomoea aquatica) and biochar improved feed intake, digestibility, N retention and growth performance of goats fed foliage of Bauhinia acuminata as the basal diet Livestock Research for Rural Development, 28 (98) http://www.lrrd.org/lrrd28/5/sili2809 8.html Sivilai, B and Preston, T.R., 2017 A low concentration of rice distillers’ byproduct, or of brewers’ grains, increased diet digestibility and nitrogen retention in native Moo Lath pigs fed ensiled banana pseudo-stem (Musa spp) and ensiled taro foliage (Colocasia esculenta) Livestock Research for Rural Development, 29 (123) http://www.lrrd.org/lrrd29/6/lert29123.html Sivilai, B, Preston, T.R., Du Thang Hang and Nguyen Quang Linh., 2018 Effect of a 4% dietary concentration of rice distillers’ byproduct, or of brewers' grains, on growth rate and feed conversion during pregnancy and lactation of native Moo Lath gilts and their progeny Livestock Research for Rural Development, 30 (20) http://www.lrrd.org/lrrd30/1/lert30020.html Taysayavong, L and Preston, T.R., 2010 Effect of rice distillers’ by-product on growth performance and digestibility in Moo Laat and Mong Cai pigs fed rice 110 bran and water spinach Livestock Research for Rural Development, 22 (165) http://www.lrr d.org/lrrd22/9/lotc22165.htm GENERAL DISCUSSION AND CONCLUSION GENERAL DISCUSSION The reasons for using indigenous pig breeds such as the Moo Lath in rural areas of Laos, usually in some form of semi-scavenging system, have been well documented (Vongthilath and Blacksell, 1999; Soukanh Keonouchanh et al., 2008; Phengsavanh et al., 2011) Bananas are grown everywhere in Laos for human food and there is a long tradition of chopping the pseudo-stem after fruit harvest and feeding it to pigs and poultry However, this abundant feed resource has received little attention from researchers, other than the observation that despite the very high moisture content (>90%) (Ffoukes et al., 1978), it was easy to ensile presumably because of the presence of soluble sugars albeit in low concentrations (Dao Thi My Tien et al., 2010; Duyet and Preston, 2013; Hang et al., 2014) By contrast, the leaves and petioles of Taro (Colocasia esculenta) have been thoroughly researched as a component of diets for pigs (Chittavong et al., 2012; Kaensombath and Lindberg, 111 2012; Hang et al., 2015) This plant, managed as a perennial forage crop, has been documented as producing yields of 250 tonnes/ha/year of fresh foliage harvested at 4-week intervals (20-30 tonnes dry matter), with 14-16% protein in the DM (Ngo Huu Toan and Preston, 2008) In a review of “forages for pigs” (Preston, 2006), it was concluded that the Taro plant was the most promising as a source of well -balanced amino acids and digestible carbohydrate The only negative attribute – the high level of oxalic acid has been shown to be controllable by ensiling and supplementation with a source of calcium (Hang et al., 2011) The objective of this thesis was to test a number of initiatives which would lead to better utilization of these two forages abundantly available in tropical ecosystems when fed to indigenous native “Moo Lath” pigs In Paper (chapter 2), the objective was to compare effects on feed intake, digestibility and N retention of replacing ensiled taro foliage with increasing proportions of ensiled banana pseudo-stem Because of the negligible protein in banana stems these were supplemented with soybean to maintain dietary protein at a suitable level The experimental diets were (% DM basis) ensiled banana pseudo-stem: 0, 5, 10 and 15% and soybean meal: 0, 2, and 4%) replacing 0, 8, 12 and 20% ensiled taro foliage with 20% broken rice in all diets The results of this experiment were supported evidence for the decision made in the conclusion to restrict the level of ensiled banana pseudo-stem to 10% Apparent digestibility of DM and crude protein, daily N retention and N retained as percent of N digested, all declined linearly as ensiled banana pseudo-stem and soybean meal replaced ensiled taro foliage This confirmed the original premise that the biological value of the protein in the ensiled taro foliage was superior to that in the combination of ensiled banana pseudo-stem and soybean meal The experiment in Paper (chapter 3) was a follow-up to findings by fellow researchers (Phanthavong et al., 2016; Sangkhom et al., 2017; Binh et al., 2017; Sengsouly et al., 2016) that by-product of beer manufacture (brewers’ grains) and local rice wine fermentation-distillation (“Hem” in Vietnam, “Kilao” in Laos) apparently acted as “prebiotics” when added in small amounts to growingfattening diets fed to cattle and goats 112 Addition of both supplements to the basal diet of ensiled taro-ensiled banana pseudo-stem, improved feed intake, digestibility and N retention, with indications of greater responses in N retention and in the biological value of the protein, for the rice distillers’ by-product It was suggested that the beneficial effect of both supplements may have been due to the presence of β-glucan, a component of the cell wall of both cereal grains and yeasts, which is known to have immunological, health-benefitting effects in humans and animals The follow-up to the previous experiment in paper (chapter 4) was the testing of the same two additives in the diets of pregnant and lactating native Moo Lath gilts and their progeny to weaning The gilts gained more body weight during gestation, and were heavier at the end of lactation, when their diet was supplemented with 4% brewers’ grains or 4% rice distillers’ by-product Litters from dams supplemented with the additives were heavier at birth, and at weaning, and grew faster than litters from un supplemented gilts Supplementation of the dams appeared to have no effect on piglet mortality at birth or during lactation, nor on live weights of piglets at birth or weaning, and did not affect overall feed DM intake However, DM feed conversion, expressed as (total feed DM consumed during pregnancy and lactation/weight of piglets weaned), was improved by 60% when the Moo Lath gilts were supplemented with 4% rice distillers’ by-product The experiment described in Paper (chapter 5) was also a follow-up to findings by colleagues (Leng et al., 2012; Silivong and Preston, 2016; Sengsouly and Preston, 2016) that biochar, the by-product from high-temperature gasification of fibrous waste (rice husks), also appeared to have “prebiotic” properties when fed to cattle and goats Biochar was fed at 1% of the basal diet of taro-banana pseudo stem in a comparison with rice distillers’ by-product at 4% Growth rate tended to be better (p=0.089) and feed conversion was improved (p=0.048) for both additives, fed separately or together, when compared with the control diet The improvements in weight gain were 20.1 and 22.9% for biochar and RDB added separately and 22.9% for the combined additives For feed conversion the relative degrees of improvement were 10.6, 12.2 and 9.30% There 113 were no benefits from combining both additives compared with feeding each one separately Whilst considerable research needs to be done, the possibility is that biochar and distillers’ by-product bind toxins or immobilize anti-nutritional compounds in feeds which are either excreted in the faces or degraded by some organisms in the animal’s gut micro biome CONCLUSIONS 1) The biological value of the protein in ensiled taro foliage was much superior to that in combinations of ensiled banana pseudo-stem and soybean meal Therefore, it is not recommended to have more than 10-15% of ensiled banana pseudo-stem in a diet based in ensiled taro foliage for native Moo Lath pigs There were apparent benefits in including 20% broken rice in this type of diet although this recommendation is based on observation and not on scientific evidence 2) Additives (4% in diet DM) in the form of rice distillers’ by-product or brewers’ grains, improved feed intake, digestibility and N retention, with a greater response in N retention and biological value of the protein for rice distillers’ byproduct 3) These additives also improved performance of gilts when fed throughout pregnancy and lactation with specific benefits in weight of piglets weaned and overall feed conversion 4) Biochar, the by-product from high temperature gasification of fibrous waste fed at 1% of diet DM, appeared to support equal benefits in growth and feed conversion in Moo Lath pigs as the 4% addition of rice distillers’ by-product There were no additional benefits by feeding both additives It is postulated that biochar and distillers’ by-product bind toxins from the feed, or neutralize antinutritional compounds, which are either excreted in the faces or degraded by some organisms in the animal’s gut micro biome It is suggested that both these additives act as “prebiotics” in neutralizing anti-nutritional components in the feed thus enhancing animal performance and wellbeing 114 IMPLICATIONS FUTURE RESEARCH 3.1 Implications The ensiled foliage (leaves and petioles) of taro (Colocasia esculenta) appears to be an excellent basal diet for native Moo Lath pigs in rural areas of Laos It grows in a wide range of natural ecosystems, with very high yields of biomass when managed as a perennial forage crop with repeated harvesting at 3-4 weeks intervals The protein in the leaves is of high biological value enabling the reduction of protein levels to the order of 12% in diet DM There are major opportunities for improvement in pig production systems in rural areas by use of feed additives that can be produced under family-farm conditions: “Kilao” the by-product from artisan fermentation/distillation to produce rice wine; “Biochar” the by-product from the carbonization of fibrous wastes in updraft gasifier stoves used for cooking, or in downdraft gasifiers for generation of an energy-rich for use in crop drying or as fuel in internal combustion engines 3.2 Future research A high-yielding forage crop such as Taro makes high demands on plant nutrients and soil ecosystems It will be advantageous to grow taro in association with legume trees/bushes that provide: leaves as feed for other livestock (eg: for goats; Preston and Gomez 2018) and fibrous stems that can be the source of biomass in gasifier stoves and downdraft gasifiers producing biochar for feeding to livestock and application in soil ecosystems It is supposed that biochar fed to pigs (and other livestock) will provide ancillary benefits (over and above the performance and welfare of the animals) when the animal excreta is recycled to the soil There appears to be little on going research in this area, but it should be of high priority as a vital component of integrated farming systems with low carbon footprints Availability of “Kilao” as a prebiotic in livestock feeds is presently dependent on associated production of rice “wine” This will not always be convenient, thus there is a need to modify the procedure eliminating the distillation stage, while ensuring the process of acid-hydrolysis believed to be the main factor in releasing the β-glucan from cereal and yeast cell walls, which is considered to be one of the active agents in 115 the “prebiotic” effect REFERENCES Binh, P.L.T., Preston, T.R., Duong, K.N and Leng, R.A., 2017 A low concentration (4% in diet dry matter) of brewers’ grains improves the growth rate and reduces thiocyanate excretion of cattle fed cassava pulp-urea and “bitter” cassava foliage Livestock Research for Rural Development, 29 (104) http://www.lrrd.org/lrrd29 /5/phuo29104.html Chittavong, M., Lindberg, J.E and Jansson, A., 2012 Feeding regime and management of local Lao pigs in Central Lao PDR Tropical Animal Health Production, 45 (1), 149-155 doi: 10.1007/s11250-012-0186-1 Dao Thi My Tien, Nguyen Tuyet Giang and Preston, T.R., 2010 A note on ensiling banana pseudo-stem with Taro (Colocasia esculenta) leaves and petioles http://w ww mekarn.org/workshops/pakse/abstracts/tien_agu2.htm Duyet, H.N and Preston, T.R., 2013 Ensiled mixed foliage of taro leaves + petioles and banana pseudo-stems as replacement of rice bran for MongCai sows in small-holder farms in Vietnam Livestock Research for Rural Development, 25 (54) http://www.lrrd.org/lrrd25/4/duye25054.htm Ffoulkes, D and Preston, T.R., 1978 The banana plant as cattle feed: digestibility and voluntary intake of different proportions of leaf and pseudo-stem Tropical Animal Production, (2), 11417 http://www.cipav.org.co/TAP/TAP/TAP33/3_3_1.pdf Hang, D.T., Binh, L.V., Preston, T.R and Savage, G.P., 2011 Oxalate content of different taro cultivars grown in central Viet Nam and the effect of simple processing methods on the oxalate concentration of the processed forages Livestock Research for Rural Development, 23 (122) http://www.lrrd.org/lrr d23/6/hang23122.htm Hang, D.T., An, T.T.X., Thuong, L., Loc, N.T., Hai, V.V., Tra, T.T.T., Hai, P.V and Ngoan, L.D., 2015 Taro (Colocasia esculenta (L) Schott): biomass yield and nutritive value for pigs Livestock Research for Rural Development, 27 (109) 116 http://www.lrrd.org/lrrd27/6/hang27109.html Hang, D.T., ThanhTra, T.T., Loc, N.T., Hai, P.V., Qui, N.D., Ngoc Linh, H.L and Ngoan, L.D., 2014 Taro (Colocasia esculenta (L) Schott) and banana pseudo-stem as energy sources for pigs in Central Vietnam Livestock Research for Rural Development, 26 (109) http://www.lrrd.org/lrrd26/6/hang26109.html Kaensombath, L and Lindberg, J.E., 2012 Effect of replacing soybean protein by taro leaf (Colocasia esculenta (L.) Schott) protein on growth performance of exotic (Landrace x Yorkshire) and native (Moo Lath) Lao pigs Tropical Animal Health and Production, 45(3), 1-7 DOI: 10.1007/s11250-012-0299-6 Keonouchanh, S., Phengsavanh, P., Stür, W., Kopinski, J S and Leterme, P., 2008 Performance of the lao local pig breed “moolath” fed a nutrient dense diet In: Proceeding of the 13th AAAP congress: Animal Agriculture and the role of small holder farmers in a global economy, Hanoi, Vietnam 199 Leng, R.A., Preston, T.R and Inthapanya, S., 2012 Biochar reduces enteric methane and improves growth and feed conversion in local “Yellow” cattle fed cassava root chips and fresh cassava foliage Livestock Research for Rural Development, 24 (199) http://www.lrrd.org/lrrd24/11/leng24199.htm Ngo Huu Toan and Preston, T.R., 2008 Taro as a local feed resource for pigs in small scale household condition Proceedings MEKARN Regional Conference 2007: Matching Livestock Systems with Available Resources (Editors: Reg Preston and Brian Ogle), Halong Bay, Vietnam, 25-28 November 2007 http://www.mekarn org/prohan/toan_hue.htm Phanthavong, V., Preston, T.R., Viengsakoun, N and Pattaya, N., 2016b Brewers' grain and cassava foliage (Manihot esculenta Cranz) as protein sources for local “Yellow” cattle fed cassava pulp-urea as basal diet Livestock Research for Rural Development, 28 (196) http://www.lrrd.org/lrrd28/11/phan28196.html Phengsavanh, P., Ogle, B., Frankow- Lindberg, B.E and Lindberg, J.E., 2011 Smallholder pig rearing systems in Northern Laos Asian-Australalian Journal of Animal Sciences, 24 (6), 867-874 Preston, T.R., 2006 Forages as protein sources for pigs in the tropics Workshop- 117 seminar "Forages for Pigs and Rabbits" MEKARN-CelAgrid, Phnom Penh, Cambodia, 22-24 August, 2006, (2) http://www.mekarn.org/proprf/preston.htm Sangkhom, I., Preston, T.R., Leng, R.A., Ngoan, L.D and Phung, L.D., 2017 Rice distillers’ byproduct improved growth performance and reduced enteric methane from “Yellow” cattle fed a fattening diet based on cassava root and foliage (Manihot esculenta Cranz) Livestock Research for Rural Development, 29 (131) http://www.lrrd.org/lrrd29/7/sang29131.html Sengsouly, P and Preston, T.R., 2016 Effect of rice-wine distillers’ byproduct and biochar on growth performance and methane emissions in local “Yellow” cattle fed ensiled cassava root, urea, cassava foliage and rice straw Livestock Research for Rural Development, 28 (178) http://www.lrrd.org/lrrd28/10/seng28178.html Silivong, P and Preston, T.R., 2016 Supplements of water spinach (Ipomoea aquatica) and biochar improved feed intake, digestibility, N retention and growth performance of goats fed foliage of Bauhinia acuminata as the basal diet Livestock Research for Rural Development, 28 (98) http://www.lrrd.org/lrrd28/5/s ili28098.html Vongthilath, S and Blacksell, S., 1999 Classical Swine Fever in Laos In: Blacksell, S (Ed.) Classical Swine Fever and Emerging Diseases in Southeast Asia Canberra, Australia: ACIAR, 122-125 http://www.aciar.gov.au/system/files/node/318/PR09 4+part+9.pdf 118 LIST OF PUBLISHED SCIENTIFIC PAPERS 1) Sivilai, B., Preston, T.R and Kaensombath, L., 2016 Feed intake, nutrient digestibility and nitrogen retention by Moo Lath pigs fed ensiled banana pseudostem (Musa spp) and ensiled taro foliage (Colocasia esculenta) Livestock Research for Rural Development, 28 (6), http://www.lrrd.org/lrrd28/1/boun28 006.html 2) Sivilai, B and Preston, T.R., 2017 Effect of level of dietary protein on growth and feed conversion of Moo Lath pigs fed a mixture of ensiled taro foliage (Colocasia esculenta) and of ensiled banana pseudo-stem (Musa spp) Livestock Research for Rural Development, 29 (34) http://www.lrrd.org/lrrd29/2/boun2 9034.htm 3) Sivilai, B and Preston, T.R., 2017 A low concentration of rice distillers’ byproduct, or of brewers’ grains, increased diet digestibility and nitrogen retention in native Moo Lath pigs fed ensiled banana pseudo-stem (Musa spp) and ensiled taro foliage (Colocasia esculenta) Livestock Research for Rural Development 29 (123) http://www.lrrd.org/lrrd29/6/lert29123.html 4) Sivilai, B Preston, T.R., Hang, D.T and Linh, N.Q., 2018 Effect of a 4% dietary concentration of rice distillers’ byproduct, or of brewers' grains, on growth rate and feed conversion during pregnancy and lactation of native Moo Lath gilts and their progeny Livestock Research for Rural Development, 30 (20) http://www.lrrd.org/lrrd30/1/lert30020.html 5) Sivilai, B., Preston, T.R., Leng, R.A., Hang, D.T and Linh, N.Q., 2018 Rice distillers’ byproduct and biochar as additives to a forage-based diet for growing Moo Lath pigs; effects on growth and feed conversion Livestock Research for Rural Development, 30 (111) http://www.lrrd.org/lrrd30/6/lert30111.html 119 6) Sivilai, B., Hang, D.T., Linh, N.Q and Preston, T.R., 2018 Effect of replacing ensiled taro foliage (Colocasia esculenta) with ensiled banana pseudo-stem (Musa spp) and soybean meal on intake, digestibility and nitrogen retention in Moo Lath pigs Livestock Research for Rural Development, 30 (54) http://www.lrrd.org/ lrrd30/3/lert30054.html 120 ... Lao name - Moo Chid (Moo Markadon or Moo Boua) 14 Figure 1.3 Lao name - Moo Lath 14 Figure 1.4 Lao name - Moo Nonghad or Moo Hmong 14 Figure 1.5 Lao name - Moo Deng or Moo Berk... region of Laos that smallholder scale pig household holding in the area such as Moo chid, Moo Lath, Moo Hmong and Moo Deng, which preliminarily described the phenotype characteristic condition... PDR Characteristics Physical characteristic, cm Length Native pig breeds/types in Laos Moo Moo Moo Chid 75-92 Moo Lath Hmong Deng 85-100 100-105 88- Height 46-54 51-70 55-76 120 60- Circumference