Uses of biochar and cassava for cattle production and methane reduction in lao pdr

 HUE UNIVERSITY 
HUE UNIVERSITY OF AGRICULTURE AND FORESTRY 
BOUNTHAVY VONGKHAMCHANH 
USES OF BIOCHAR AND CASSAVA FOR CATTLE 
PRODUCTION AND METHANE REDUCTION 
IN LAO PDR 
DOCTOR OF PHILOSOPHY IN ANIMAL SCIENCES 
HUE, 2021 
 HUE UNIVERSITY 
HUE UNIVERSITY OF AGRICULTURE AND FORESTRY 
BOUNTHAVY VONGKHAMCHANH 
USES OF BIOCHAR AND CASSAVA FOR CATTLE 
PRODUCTION AND METHANE REDUCTION 
IN LAO PDR 
SPECIALIZATION: ANIMAL SCIENCES 
CODE: 9620105 
DOCTOR OF PHILOSOPHY IN ANIMAL SCIENCES 
SUPERVISORS: 
1: ASSOC. PROF. DR. LE VAN AN 
2: DR. DUONG THANH HAI 
HUE, 2021 
 GUARANTEE 
I hereby guarantee that scientific work in this thesis is mine. All results 
described in this thesis are righteous and objective. They have been published in the 
journal of Champasak Province, Lao PDR, journal of Livestock Research for Rural 
Development (LRRD), JASTD, Lao PDR, and Journal of Animal Husbandry Sciences 
and Technics (JAHST), Vietnam. 
Hue University, 2020 
Bounthavy, PhD student 
i 
DEDICATION 
To my parents, my wife (Sangsavanh Niemthachit), daughter (Sangmany 
Vongkhamchanh) and son (Pharkdy Vongkhamchanh). 
ii 
ACKNOWLEDGEMENTS 
I would like to express my sincere gratitude and appreciation to my major 
advisor, Assoc. Prof. Le Van An, Department of Animal Husbandry, Fuculty of Animal 
Husbandry and Veterinary Medicine, University of Agriculture and Forestry, Hue 
University for his precious advice, guidance on thesis, encouragement, and constructive 
comments. My deeply grateful and sincere gratitude is extended to my co-advisor, 
Duong Thanh Hai, Ph.D., Department of Animal Husbandry, Fuculty of Animal 
Husbandry and Veterinary Medicine, University of Agriculture and Forestry, Hue 
University for his kindness in advising research proposal and experiment. I am grateful 
to all professors, teachers, and staff of the Faculty of Animal Husbandry and Veterinary 
Medicine for the suggestion, which enables me to complete my work. I would like to 
thanks MEKARN II project and Hue University of Agriculture and Forestry for 
providing the financial support for my study that enables me to complete this study. 
Finally, I am grateful to my family for their financial support, care, and love. 
I would like to express my deep gratitude to Professor. Thomas Reg Preston, 
for guiding the experiments during the study and helping me to author my journal. I 
would also like to extend sincere thanks to several people who facilitate, encourage, 
and support the whole Ph.D. course such as Professor. Dr. Ewadle, International 
Coordinator MEKARN II project; Dr. Vanthong Phengvichith, National Agriculture 
and Forestry Research Institute (NAFRI), Dr. Daovy Kongmanila, National 
Univerisity of Lao PDR; Dr. Kieu Borin, MEKARN II regional coordinator; Dr. Ngo 
Tung Duc, the Head of Education Department, Hue University of Agriculture and 
Forestry. Warm thanks are extended to my Ph.D. classmates from the three countries: 
Laos, Vietnam, and Cambodia, for sharing the culture, friendship, and creating a warm 
atmosphere throughout the Ph.D. course. 
iii 
ABSTRACTS 
Cattle are regarded as one ruminant of livestock that is expressed the 
importance for smallholder and account are more than 50% of cash income in Laos. 
However, barriers to cattle production are mainly limitation of feed qualities and 
quantities, and methane emission by enteric fermentation where consider as one source 
of greenhouse gases. Therefore, these studies aimed to evaluate the utilization of 
cassava supplied by biochar to mitigate methane production in an In vitro rumen 
incubation and incorporated with the diets for fattening local yellow cattle. 
Chapter 2 (experiment 1) 
The rice straw and cassava leaf meal were used as substrate. Urea was used as a 
source of NPN and protein. Gas production and methane in the gas were measured 
over successive 6 h intervals for 24 h, after which the residual dry matter (DM) in the 
substrate was determined by filtration. During the fermentation intervals (18 – 24 h) 
there were significant differences in gas production between two substrates, rice straw 
(276.67 ml) and cassava leaf meal (515 ml) (p<0.05). The levels of biochar (0, 1 and 
2%) were no effect in gas production of the substrates, in contrast, biochar can be 
reduced methane as well as 21.292, 20.417 and 19.667% respectively (p<0.05) but 
between 1 and 2% of biochar were not shown any difference in decreasing the 
methane production. The cassava leaf meal (78.479%) was digested significantly 
higher than rice straw (70.139%). Biochar did not affect the proportion of DM 
mineralized and digestibility after 24 h but reduced the production of methane per unit 
DM mineralized. 
Chapter 3 (experiment 2) 
Dried, ensiled and fresh cassava roots were used as an energy substrate. Urea 
and cassava leaf meal were used as sources of NPN and protein. Gas production and 
methane in the gas were measured over successive 6 h intervals for 24 h, after which 
the residual dry matter (DM) in the substrate was determined by filtration. There were 
no differences in gas production among the cassava root treatments during any of the 
fermentation intervals. By contrast, methane percent in the gas was lowest in the fresh 
root and highest in the dried root, with intermediate values for the ensiled root. The 
total DM mineralized after 24 h fermentation was not affected by root processing. Gas 
production tended to be reduced (p=0.07) by biochar for the 18-24 h interval but was 
not affected at the earlier intervals. The methane concentration in the gas was reduced 
by biochar in the 18-24 h fermentation interval, but there was no effect for 
fermentation intervals of 0-6, 6-12 and 12-18 h. Biochar did not affect the proportion 
of DM mineralized after 24 h but reduced the production of methane per unit DM 
mineralized. 
iv 
Chapter 4 (experiment 3) 
Twelve local yellow cattle with an initial live weight of 90 – 105 kg were used 
to evaluate the efficacies of fresh cassava root incorporated with biochar. The 
experimental design was arranged in a completely randomized design (CRD) with 
three replications of each treatment. The factors were different levels of fresh cassava 
root (CTL, 10, 20, and 30%) with 1% biochar in diet DM. The experiment was carried 
out for 84 days with an extra 14 days for adaptation to the pens and diets. Fresh 
cassava root (FC) was offered as a basal diet supplemented with urea, elephant grass, 
and rice straw. The addition of fresh cassava root by different levels was not shown 
any effects in feed intake but when increased the level of fresh cassava root as 30% 
incorporated with 1% biochar of diet DM found the cattle were displayed significant 
growth rate as high as 252.4 g/d (p<0.05). 
Chapter 5 (experiment 4) 
In a 56-day experiment with 6 local yellow cattle fed ensiled cassava root-urea, 
brewers‘ grains and rice straw, there were indications (p=0.08) that after an initial 4-
week adaptation to the diet, the cattle were growing faster when 1% of biochar 
(derived from rice husk) was incorporated in the diet was 0.635 of LW gain, kg/d. 
Chapter 6 (experiment 5) 
Ensiled cassava root incorporates different levels of dry cassava leaf that is used 
as a source of bypass protein for fattening local yellow cattle in Lao PDR, nine local 
yellow cattle with an initial live weight of 90 – 100 kg live weight (LW) were used in 
this study. The experimental design was arranged in a completely randomized design 
(CRD) with three replications of each treatment. The factors were different levels of 
dried cassava foliage (CTL, 25, and 50% of total diet DM). The experiment was 
carried out for 14 days for adaptation to the pens and diets. Ensiled cassava root was 
offered as a basal diet supplemented with rice straw and mineral block, and adding 
dried cassava foliage by different levels. The results indicated that the increase of dried 
cassava foliage levels was displayed the effects in feed conversion rate (FCR) (p<0.05) 
and when increased the level of dried cassava foliage at 50% of total diet DM 
incorporated with the diet DM found the cattle were presented significant growth rate 
as high as 0.304 kg/d of ADG (p<0.05). 
From experimental results can conclude that 1% biochar incorporated with 
fresh or ensiled cassava root can be reduced methane emission in an In vitro rumen 
fermentation. 1% biochar (derived from rice husk) incorporated with ensiled cassava 
root, urea, brewers‘ grains and rice straw there were positive indications to increase 
the growth rate of cattle and by-product from cassava production (dried cassava 
foliage) was indicated the benefit of utilization for fattening cattle. 
Keywords: Greenhouse gases, HCN, fresh cassava root, cassava leaves, diets 
v 
TABLE OF CONTENTS 
GUARANTEE ............................................................................................................... iii 
DEDICATION.................................................................................................................. i 
ACKNOWLEDGEMENTS ............................................................................................ ii 
ABSTRACTS ................................................................................................................ iii 
LIST OF FIGURES ....................................................................................................... xii 
LIST OF TABLES ...................................................................................................... xiii 
LIST OF ABBREVIATIONS, SYMBOLS AND EQUIVALENTS ........................... xvi 
INTRODUCTION ........................................................................................................... 1 
1. PROBLEM STATEMENT ......................................................................................... 1 
2. AIMS AND OBJECTIVES OF THE STUDY ............................................................ 3 
2.1 AIMS OF THE STUDY ............................................................................................ 3 
2.2. OBJECTIVES OF THE STUDY ............................................................................. 3 
3. RESEARCH HYPOTHESES ...................................................................................... 4 
4. SIGNIFICANT/INNOVATION OF THE DISSERTATION ..................................... 4 
5. REFERENCES ............................................................................................................ 4 
CHAPTER 1. LITERATURE REVIEW ......................................................................... 9 
1. CATTLE POPULATION AND PRODUCTION IN LAO PDR ................................ 9 
1.1. THE ROLE OF CATTLE ........................................................................................ 9 
1.2. CATTLE POPULATION ......................................................................................... 9 
1.3. GENERAL CHARACTERISTIC OF HOUSEHOLD S‘ CATTLE RAISING .... 12 
1.4. CATTLE PRODUCTION ...................................................................................... 12 
1.4.1. BREEDS AND BREEDING ............................................................................... 12 
1.4.2. Cattle meat consumption ..................................................................................... 13 
1.4.3. Cattle production system ..................................................................................... 14 
1.5. INFECTIOUS DISEASES OF CATTLE ............................................................... 16 
1.6. MARKET SYSTEM OF CATTLE ........................................................................ 17 
1.7. OPPORTUNITIES AND CONSTRAINS OF CATTLE PRODUCTION ............ 19 
1.7.1. Potentials of cattle production ............................................................................. 19 
1.7.2. Constrains of cattle production ............................................................................ 19 
vi 
2. LOCAL FEED AND FEEDING ............................................................................... 20 
2.1. SITUATION OF FEED RESOURCES ................................................................. 20 
2.2. IMPORTANCE OF BY-PRODUCT ..................................................................... 20 
2.3. BY-PRODUCT FROM INDUSTRIES .................................................................. 21 
2.3.1. Cassava pulp ........................................................................................................ 21 
2.3.2. Brewers‘ grain ..................................................................................................... 22 
2.3.3. Rice distillers‘ by-product ................................................................................... 23 
2.3.4. Molasses .............................................................................................................. 23 
2.4. BY-PRODUCT FROM AGRICULTURE ............................................................. 24 
2.4.1. Agricultural by-product properties ...................................................................... 24 
2.4.2. Straw from cereal crop ........................................................................................ 24 
2.4.3. By-product from cassava production................................................................... 25 
2.5. UTILIZATION OF BY-PRODUCT FOR RUMINANT ....................................... 25 
2.6. FEEDING THE RUMEN MICROBES ................................................................. 26 
2.6.1. Multi-nutrient blocks ........................................................................................... 27 
2.6.2. Ammoniation ....................................................................................................... 27 
3. GREENHOUSE GAS FROM AGRICULTURE AND MITIGATING WAYS ...... 27 
3.1. GREENHOUSE GAS FROM AGRICULTURE ................................................... 27 
3.2. THE LIVESTOCK SECTOR ................................................................................. 28 
3.3. GREENHOUSE GAS MITIGATION FROM AGRICULTURE .......................... 29 
3.4. LIVESTOCK AND MANURE MANAGEMENT ................................................ 30 
3.5. CONSEQUENCES OF GLOBAL WARMING .................................................... 30 
3.6. CLIMATE AND NATURAL DISASTERS IN LAO PDR ................................... 31 
3.7. GREENHOUSE GASES EMISSION FROM LIVESTOCK IN LAO PDR ......... 32 
4. BIOCHAR ................................................................................................................. 32 
4.1. PRODUCTION OF BIOCHAR ............................................................................. 32 
4.2. THE INFLUENCE OF BIOCHAR FOR MITIGAT ... et, cattle were 
growing as fast as about 0.635 kg/d of live weight gain. 
119 
Dried cassava foliage was supplied as a bypass protein source to incorporate 
with ensiled cassava root and rice straw for fattening local yellow cattle which the 
employment of 50% dried cassava foliage of total diet DM was significantly improved 
the growth rate and feed conversion rate of cattle as high as were 0.304 kg/d and 14.9, 
respectively (p<0.05). 
3. IMPLICATION AND FURTHER RESEARCH 
The finding of this study has significantly illustrated the utilization of cassava 
root as a source of energy, brewer‘s grain, dried cassava foliage, and urea are used as a 
source of by-pass protein, and rice straw and elephant grass use as a fiber source for 
fattening local yellow cattle in Lao PDR. The application of 1% biochar has a positive 
indication to employ as an ingredient incorporates with diets to improve the live weight 
gain of cattle and it is ensured that can be applied as an additive feed to mitigate 
methane emission from cattle. This study is useful for other researchers to apply the 
methodologies and results of an experiment to implement their study in the future. 
Further study should attentively have analyzed the rumen environment by 
taking rumen fluid to estimate the percentage of acetic acid, propionic acid, and 
butyric acid to find the effects after offering the experimental feed during 
experimenting. An ecology system in the rumen needs to evaluate either the increasing 
or decreasing of microorganism and play attention to classify the actions of each 
microorganism after feeding the cattle. The blood of cattle needs to analyze for finding 
the toxicity or amino acid to make clear the understanding of the effects of diets. 
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PUBLICATIONS LIST 
I. Bounthavy Vongkhamchanh., Preston, T.R., Leng, R.A., Le Van An and 
Duong Thanh Hai 2018. Effect of biochar on growth performance of local yellow 
cattle fed ensiled cassava roots, fresh brewers‘ grains and rice straw. Livestock 
Research for Rural Development. Volume 30, Article #158. Available at: 
II. Vongkhamchanh, B., An, L. V and Hai, D.T., 2018. The effects of different 
levels of fresh cassava root with biochar on growth performance of local yellow cattle 
in Lao PDR. J. Ag. Sci. Tech. Dev. 3(1): 388-395. Available at: 
III. Vongkhamchanh B., Boualy S., Izuru S., An, L.V. and Hai, D.T., 2019. The 
effect of dried cassava foliage with ensiled cassava root on grow performance of local 
yellow cattle in Lao PDR. Journal of Animal Husbandry Sciences and Technics 
(JAHST) (249): 50-54. Available at: 
https://csdlkhoahoc.hueuni.edu.vn/data/2019/11/2019_TAPCHICHANNUOI249.pdf