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INTRODUCTION
1. The demand of the research study
Currently, in order to adequate domestic consumption as well as export market
demand for pork consumption, beside increasing of rearing local swine breeds and
hybrid of exotic with local breeds, it’s a tendency that to keep hybrids with 4 – 5
exotic swine breeds which attracts more attention of farmers to expand their
production. A part from improvement of the breed in term of productivity and
quality, it also requires improvement in term of nutrition for animals, especially
research on requirement of protein and amino acid for growing pigs. The modern
opinion on animal nutrition considers that protein requirement is the requirement of
amino acids. If there is inadequacy of essential amino acids supplement (in term of
quantity and amino acid balance) then it would lead to retard of grow in animal
which would affect production and economic efficiency. On the other hand, though it
is enough protein or even surplus protein in pig diet but this is unbalanced of
essential amino acids then digestibility and feed utilization efficiency of the diet will
be reduced. Thus, the reduction of protein level in the diet and supplement of
synthesized amino acids are the best solutions to adequate animal requirement of
amino acids and also reduce environmental pollution in pig production.
When calculate protein requirement in pig diet, the calculation of protein levels
are usually based on the studies on protein requirement or just adopt the published
standard for the main amino acids requirements such as lysine and methionine,
however, other amino acids requirement is not estimated. In order to meet amino
acids requirement for pig. Pig producers and feed processing companies usually use
the formula with high level of protein to formulate feed without taking into account
the insufficient of protein utilization due to the surplus of amino acids which leads to
a surplus of nitrogen and sulfur excreted into environment. In addition, the price of
protein sources of animal and plant origin such as soybean meal, fishmeal etc.
increases rapidly, which negatively affect economic efficiency of pig production.
With the development of biotechnology, it is possible to produce amino acids
from mirco-organism and from chemical elements with lower price, especially the
production of essential amino acids such as lysine, threonine and methionine. The
advanced of amino acids production technology creates opportunity to carry out and
apply the studies on essential amino acids requirement in order to adequate amino
acids requirement for pig, efficiency utilization of protein, reduction of environment
pollution, and also normal growth of animals. Based on the above reasons, we
undertake the study: “Determination of optimal protein level in exotic fattener
pig’s diet bases on balancing some amino acids”
2. Objective of study
- Determining diet formula for 4-breeds exotic hybrid with optimal protein
level bases on balancing some essential amino acids includes: lysine, methionine and
threonine in order to improve grow capacity, feed utilization efficiency and to reduce
urinal and faecal nitrogen and phosphorus excretion.
- Formulating some formulas base on the local ingredients with optimal protein
and amino acids level to ensure production efficiency of exotic 4-breeds hybrid and
to reduce environment pollution in pig production.
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3. The effective of study
3.1. In term of practice effectiveness
The study has proposed 2 diet formulas with an optimal protein level and a
balance of some synthetic amino acids (lysine, methionine and threonine) for exotic
fattener swine. The diet formulas have ensured the good performance of pig, the
formulas not only saved protein but also reduced environment pollution. Results of
study have been applied in commercial production at Dai Minh feed processing
company – Song Cong Town, Thai Nguyen and other intensive pig production farms
in the area.
3.2. In term of scientific effective
The results of study has provided some scientific data to prove the efficiency of
synthetic amino acids utilization to balance diet on the “Ideal protein” principle in
order to reduce the total protein level but ensure production efficiency and reduce
environment pollution.
4. Scope of study
- Objects of study
+ Commercial hybrid of 4 exotic pig breeds between male F1 (Pietrain x
Duroc) x female F1 (Landrace x Yorshire)], Starting bodyweight of experimental
units was from 18.15 - 18.22 kg/pig (equivalant to 56 day of age).
+ Feed ingredients to formulate experimental diet include yellow maize,
soybean meal, rice bran grade 1, fish meal, vegetable oil, L-lysine, DL- methionine,
L-threonine, premix vitamin + trace minerals, dicalciphosphate and lime stone
powder.
- Place of study
+ The experiments were carried out at several intensive exotic pig farms
included Cương Hường Farm - Tích lương - Thái Nguyên, Hùng Chi Farm - Lương
Sơn - Sông Công, Thái Nguyên.
+ Cage experiments were carried out at the experimental unit of Institute of
Life Sciences, Thai Nguyen University.
+ Feed, pork analysis and nitrogen, sulfur in urine, faeces measurement were
undertaken at Institute of Life Sciences, Thai Nguyen University.
+ Complete feeds for experiments were produced and supplied by Dai Minh
feed processing company – Song Cong Town
5. New contributions of the study
- The study has determined the protein and some essential amino acids level in
local ingredients based complete feed for exotic 4-breed hybrid which ensured well
pig performance, high percentage of lean meat and good feed utilization efficiency.
- The utilization of diet with optimal protein and amino acids level for exotic 4-
breed hybrid has reduced urinal and faecal nitrogen and sulfur excretion, contributed
to environment pollution reduction.
6. Thesis structure
The thesis consists of 107 pages, includes introduction part, 3 chapters and
conclusion part, of which there are 28 data tables, 10 graphs/picture for illustration,
132 references, of the references, there are 54 Vietnamese references, 74 English
references, 02 French references and 02 German references.
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CHAPTER 1: SCIENTIFIC OVERVIEW
1.1. Scientific basis of study
1.1.1. Scientific basis of protein digestion and absorption in pig
1.1.2. Protein and amino acids metabolism in pig
1.1.3. Requirement and method to balance protein and amino acids
1.1.4. Ideal protein in fattener diet
1.2. Related research in domestic and in abroad
- Domestic related research
Research and studies in order to determine nutrients requirement for animals
are regular the tasks that require the continuous investigation. Although nutrients
requirement for fattener was undertaken in early time and this study has resulted in a
number of reports, however, with the state of the art of breeding technology, pig
breeds are also being improved with higher percentage of lean meat which requires
the accordingly increased in nutrients requirement. In addition, now a day, due to
synthetic amino acids are produced intensively that allows not only research on
protein requirement but also amino acids requirement for pig. Research results are
mostly focused in:
- Research on optimal protein and amino acids level: Results on protein and
amino acids supplement from different feed ingredients are differed for every pig
breed. The principle of reducing crude protein level with supplementary of some
synthesis amino acids has the advantage of using low dietary protein level with
supplementary of synthesis amino acids which not only improves animal
performance but also positively favors environment protection. However, if dietary
protein level is too low, then regardless of adequacy supplementation of synthesis
amino acids, pigs still show depressed in growth. This issue was proved by study
done by Nguyen Nhi et al. (1995), Nguyen Bach Tra et al. (1995)…
- Research results on amino acids/energy were reported by several authors
such as Ngoc Hung et al. (2000), Vu Thi Lan Phuong (2001)…
- Research on protein and amino acids digestibility was undertaken by: Tran
Quoc Viet et al. (2001) who used crome oxide as marker to determine digestibility
has reported that nitrogen digestibility in pig at bodyweight (BW) from 20-50 kg was
75.67% - 77.54% - 78.82% in response to dietary crude protein ranged 17-16-15%,
respectively. At period of 50-100kg of BW , nitrogen digestibility was 85.81% -
86.03% - 86.22% response to crude protein level of 15 - 14 - 13%. It could be
concluded that if dietary protein level in the diet decreased by 1% then nitrogen
digestibility increased by 0.19% - 1.87% which depended on BW. Hồ Trung Thông
(2006) also reported that protein intake affects protein digestibility and N excretion of
grower 3-breed hybrid pig of male Pietrain x female (Durroc x Landrace). Increased
dietary protein level from 4.58% - 30.02% (Dry matter basic) the apparent protein
digestibility increased gradually and tends to reach its maximum value. Therefore,
dietary protein level in the formulated diet should not lower than 14%. Protein
digestibility is calculated by true protein digestibility which is protein digestibility
after subtract endogenous protein. True protein digestibility is not depended on
protein intake. The faecal and urinal N excreted increased when protein intake
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increased, however, the total N excretion increased is mainly caused by the increased
of urinal N excretion.
- Related research topic in Abroad
Scientist around the world mostly focused in:
- Protein and essential amino acids requirement for pig; phosphorus in amino
acids. The current research tend to determine nutrients requirement for pig is to
determine the optimal amino acids level of the ideal protein level.
- The balancing relationship between essential amino acids and amino acids
requirement for growing pig.
- Research on effect of dietary protein and amino acids level in pig diet on
environment issue.
- Research to apply synthesis amino acids supplementation in pig production.
Hence, gathering information of related domestic and abroad research topic on
reasonable reduction of dietary protein level bases on balancing essential amino
acids to grow performance of lean pork production and to environment protection has
revealed that guidelines on protein and amino acids level for growing pig at different
stages in order to exploit maximum growth trait of the lean pork breed and also
reduce environment pollution has been well and synchronically undertaken and
documented by many researchers all over the world. However, in the climate and
ecological condition of Viet Nam, these research are still scattered and
unsynchronized.
Based on the actual lean meat pig production of Viet Nam in open housing
condition, it’s a demand to have a comprehensive research on reduction of dietary
protein level bases on balancing some essential amino acids to growth capacity of
pig and to contribute to environment protection is an urgent demand. To solve this
urgent scientific matter not only to ensure the normal growth of pig but also to save
the expensive protein sources in order to reduce production cost, especially, this
research contributes for environment protection which is now under a number of
pollution threats, of which, intensive animal production wastes is also in account.
CHAPTER 2: MATERIALS AND METHODS
2.1. MATERIALS
- Animals
Commercial exotic 4-breeds hybrid pig of male F1 (Pietrain x Duroc) x female
(Landrace x Yorshire), Initiate BW in average 18.15-18.22kg/pig (equivalent to 56
days of age), experiments were last for 90 days.
- Materials
Feed ingredients to formulate experimental diets include: yellow maize, soybean
meal, rice bran class 1, fish meal, vegetable oil, L-lysine, DL- methionine, L-threonine,
premix vitamin + trace minerals, dicalciphosphate and fine ground lime stone.
The experiments were combined at 3 intensive pig farm in Thai Nguyen and the
experiment diets were produced and supplied by Dai Minh Feed Processing Ltd Company.
2.2. RESEARCH CONTENTS
1. Determining effect of dietary protein and essential amino acids level in complete
diet on 4-breeds exotic hybrid pig.
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2. Research on relationship between different dietary level with balancing some
essential amino acids in complete feed and faecal and urinal nitrogen excretion.
3. Choosing several local ingredient based feed formulas and experiment in exotic
pig production farms at mass production scale.
2.3. METHODS
2.3.1. Study 1: Determining effect of dietary protein and essential amino acids level
in complete diet on 4-breeds exotic hybrid pig
2.3.1.1. Overall methodology of experimental design and conduction.
- Experimental methodology: The experiment was conducted based on plots
comparison which taken into account the uniformity of breed, age, BW, sex, health
status, nutrition and care condition, hygiene and ambient environment condition.
Each experiment was conducted triples. Feed and feed processing: Feed ingredients
were chemically analysed before processing and were stored through out
experimental period. Experimental feed formulas were calculated by OPTIMIX
software from Institute of Biology and Vet Pharmacology Research – Czech Repubic.
Feed processing: Raw ingredients were finely grounded, feed supplements or
additives were bought from commercial providers. Complete feeds were formulated
and mixed base on “oil spills” method (for trace additives) and then mixed by vertical
mixer with capacity of 500 kg/batch, each mixing has ensured provide enough feed
for 5- 7 days consumption.
- Feeding and animal care: Pigs were housed in open air housing condition,
concrete/solid floor, ensured warm in winter and well ventilation during summer,
semi-automatic feeder and nipple drinker were used. Experimental pigs were
accessed to feed ad libitum feed was provided 2 times a day morning and afternoon.
2.3.1.2. Experimental design
The experimental design to employ 297 pigs which divided to 9 experimental
units with 9 complete feed formulas, each experimental unit housed 11 pig and
repeated triples at the same time. Initiate BW approximately 18 kg/pig equivalent to
56 days of age, the experiments lasted for 90 days. The experiment was designed
with 2 simultaneous factors design consists of 3 dietary protein levels, there were 3
lysine levels in accordance with each dietary protein level. Both experimental factors
were reduced in accordance to stages of grow of pig as follow:
- Growing period: There were 3 dietary protein level which were 18-17-16%
based on metabolic energy of 3200 Kcal ME/kg. For each dietary protein level was
lysine levels of 11-10-9 g/kg. Lys/ME ratio was 3.44 - 3.13 and 2.81 g/1000 Kcal
respectively.
- Fattener period: There were 3 dietary protein level 16-15-14% respectively
base on metabolic energy level of 3100 Kcal ME/kg. For each dietary protein level
there were 3 lysine levels 10 - 9 - 8 g/kg respectively. Lys/ME ratio was 2.81 -2.50
2.19 g/1000 Kcal respectively.
Of all experimental diet formulas, essential amino acids levels were:
Threonine and Methionine were balanced by Lysine (ARC. 1981), as detailed follow:
Lysine: 100; Threonine 65 and Methionine+cystine 55(%). In order to ensure amino
acids content as designed, we supplied some synthesis amino acids such as: L-lysine,
