Towards a Blockchain Architecture for Animal Sanitary Control

Glenio Descovi

, Vin

ıcius Maran

, Denilson Ebling

and Alencar Machado

1,2

Technology Center, Federal University of Santa Maria, Santa Maria, Brazil

Polytechnic College, Federal University of Santa Maria, Brazil

Laboratory of Ubiquitous, Mobile and Applied Computing (LUMAC), Federal University of Santa Maria,

Keywords:

Animal Sanitary Control, Epidemiology, Blockchain, Consensus Algorithms.

Abstract:

It is known that Blockchain technology is widely used in cryptocurrency transactions, the technology has

become popular with Bitcoin but recently, it has been applied in many areas, including the animal sanitary

control. It can be said that Blockchain is an immutable ledger, where systems can store transactions, docu-

ments, history, countless data generated in any process. In Brazil, an animal sanitary control platform called

Plataforma de Defesa Sanitaria Animal (PDSA-RS) was recently proposed and is widely used in the state of

Rio Grande do Sul. Actually, the PDSA-RS uses a centered server with relevant information for the animal

sanitary control process. This work presents the process of deﬁning and integrating the PDSA-RS with a pri-

vate Blockchain managed by a software architecture. The main goal of this integration is to give traceability,

immutability and transparency in the existing process and the data generated in the certiﬁcation of poultry

establishments that are part of the animal sanitary control. In the evaluation of the integration process, it

was possible to observe that it the blockchain extension offered persistence, anonymity and auditability of the

information related to the animal sanitary control.

1 INTRODUCTION

Blockchain recently attracted attention from indus-

try and academia, becoming popular with cryptocur-

rencies, speciﬁcally Bitcoin (Kosba et al., 2016).

Blockchain is on the rise, where it is not only be-

ing applied to cryptocurrency transactions, but also

in other areas, such as document management, as it is

versatile and has numerous applications. Its charac-

teristics, such as security, immutability, transparency,

make it a great tool for managing and auditing infor-

mation. Due to this growth in applications involving

Blockchain technology, there has been a huge growth

in demand for blockchain engineers in recent years.

The technology was developed to solve some

problems that have existed for some time, such as, re-

liability of transactions (banking or not), immutability

of information, that is, permanent (the data informed

will never change), document management, a single

repository of information, among others (Zheng et al.,

2018), implemented in a network distributed in pub-

lic blockchains and in a single network in private

blockchain. However, some problems arise as vul-

nerabilities and scalability according to the amount of

information contained in it.

The epidemiological control of diseases has prob-

lems that the Blockchain usage ﬁts to solve. There

is great importance in the epidemiological control of

diseases worldwide, which was even more evident

with COVID-19 pandemy. The transmission of dis-

eases often occurs through contact with infected an-

imals and with the increase in meat consumption the

risks of spreading diseases increase even more (Arora

and Mishra, 2020). This shows the importance of epi-

demiological control of diseases in animals so that

humans are not infected by existing pathogens that

put people’s lives at risk. To archive this goal, the

information related to this control must be secure, im-

mutable and transparent (Arora and Mishra, 2020).

Continuing in this context of epidemiological con-

trol, an Plataforma de Defesa Animal do Rio Grande

do Sul (PDSA-RS) is being implemented in Brazil,

which begins its operation in September/2020. The

PDSA-RS acts directly on the traceability of informa-

tion related to certiﬁcation of breeding birds in the

Brazilian state of Rio Grande do Sul. Is this context,

this work proposes the integration of the Blockchain

to give immutability to information and crete a unique

repository for research or auditability of the data gen-

erated in the poultry health of the state of Rio Grande

Descovi, G., Maran, V., Ebling, D. and Machado, A.

Towards a Blockchain Architecture for Animal Sanitary Control.

DOI: 10.5220/0010483303050312

In Proceedings of the 23rd International Conference on Enterprise Information Systems (ICEIS 2021) - Volume 1, pages 305-312

ISBN: 978-989-758-509-8

305

do Sul in the PDSA-RS. First, the work addresses a

brief explanation of what it is a Blockchain, its archi-

tecture and operation and where it is intended to be

used, in this case in the certiﬁcation of poultry farms

(genetics) of breeding birds in the state of Rio Grande

do Sul, to guarantee the immutability of the data gen-

erated in this process, thus improving the auditability

of the information

With the goal of understand the operation and ap-

plicability of the Blockchain for animal health, in

which the objective is to obtain a high conﬁdence

traceability of the information generated in the pro-

cess, conﬁdence based on the characteristics of the

Blockchain, thus maintaining the information im-

mutable, facilitating the auditability and traceability

of the data generated in the process. Immutable, in

this context immutability is one of the main charac-

teristics of Blockchain technology, it is about main-

taining the data once entered in the ledger without

changes, ensuring that the information never under-

goes changes (Zheng et al., 2018). With this objec-

tive, a software architecture was deﬁned and proto-

typed. The prototype was applied in a scenario based

on the real data, generated by the PDSA-RS.

The paper is organized as follows: in Section 2,

we present the main related concepts necessary for

the article. In Section 3, we present the context of the

research itself. In Section 4 we present the case study

carried out by the research and the discussion of the

lessons learned in the integration process. In Section

5 we present the conclusions of this work and future

research possibilities.

2 CONCEPTUAL FOUNDATION

This section contextualizes the basic concepts used in

the research and implementation of the prototype in-

tegrated to the PDSA-RS.

2.1 Blockchain

Blockchain is a technology on the rise in which it

was ﬁrst proposed in mid-2008 and implemented in

2009 (Nakamoto and Bitcoin, 2008). It can be con-

sidered as a ledger, where each transaction is regis-

tered in a block chain, a chain in which it grows grad-

ually when inserting new blocks to it (Zheng et al.,

2018). The Blockchain technology has some charac-

teristics that make it popular: Decentralization, Per-

sistence, Anonymity and Auditability of the informa-

https://www.gov.br/agricultura/pt-

br/assuntos/sanidade-animal-e-vegetal/saude-

animal/programas-de-saude-animal/pnsa (portuguese)

tion contained in the block chain. Technology can

work in an decentralized environment since it uses se-

curity techniques (cryptographic hash, digital signa-

ture based on asymmetric cryptography) and the dis-

tributed consensus mechanism (Zheng et al., 2018),

thus reducing costs and improving the efﬁciency of

transactions, without the need for a mediator, such as

a registry ofﬁce.

2.1.1 Blockchain Architecture

It is a chain of blocks or sequence of blocks, which

contains the record of transactions carried out and

added to the blockchain (Wang et al., 2019a). Each

block has a reference to the previous block, the ref-

erence is a hash value for the entire block (Zheng

et al., 2018), so if there is a change in the block,

the change will be noticed. According to (Zheng

et al., 2018), the block has the following elements:

header and body. The Header element has the fol-

lowing information: (i) Block version, (ii) Hash of

the parent block, (iii) Hash value of all transactions

in the block, (iiii) Timestamp of block creation, (iiiii)

Nonce

, value added to the block to give variability to

the hash value (Miers et al., 2019);

The body of the block is composed of a transac-

tion counter, the blockchain uses an asymmetric en-

cryption mechanism to validate the authentication of

transactions (Omohundro, 2014). Within the architec-

ture, it is necessary to talk about the digital signature,

where each user has a pair of keys, one public and one

private, in which the private key is used to sign the

transactions. The most widely used block chain al-

gorithms like the digital signature blockchain include

the elliptic curve algorithm (ECDSA) (Johnson et al.,

2001).

2.1.2 Blockchain Main Pillars

Blockchain technology has some fundamental pillars

(Wang et al., 2019b):

• Has a Ledger, which is a base of data that stores

information and is conﬁgured in a distributed

manner. Therefore, this Ledger also guarantees

the transparency and immutability of the informa-

tion;

• Cryptography, each participant within the net-

work, as well as each transaction is encrypted by

Nonce: Unique random number that in Bitcoin is used

in the validation of blocks. It is used to ﬁnd a valid hash

value, the greater the difﬁculty of the nonce, that is, the

greater the number of zeros to the left of the nonce num-

ber, the number of possible valid hashes decreases. (Miers

et al., 2019)

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the participant himself, he has a digital certiﬁcate

with which he will sign these transactions. There-

fore, the entire transaction within a blockchain is

privately and encrypted;

• Smart Contracts, are the business rules that are

applied to this data;

• Consensus, guarantees stability and validates the

transactions to guarantee a transactional order

within the blockchain network, for that there are

consensus algorithms.

2.1.3 Consensus Algorithms

In this section, we will focus on four consensus algo-

rithms. Private Blockchains are best advised to man-

age an organization’s internal information. All nodes

in a blockchain have an exact copy of the blocks that

make it up (Miers et al., 2019). For a new block to be

inserted, the blockchain uses consensus algorithms.

The three algorithms presented in this paper are:

• Proof-of-Work (PoW): This algorithm is cur-

rently used in Bitcoin, it has a huge energy expen-

diture. All nodes in the network need at all times

to calculate a speciﬁc Hash using different nonces,

when ﬁnding this Hash the node informs the other

nodes, they must conﬁrm this Hash and then vali-

date the transaction. Because of this behavior, this

algorithm is called mining (Miers et al., 2019).

• Proof-of-Stake (PoS): Compared to PoW, PoS

saves more energy and is more effective, because

instead of requiring nodes to mine, in this algo-

rithm the highest possibility of mining the next

block is from those who have a larger amount of

coins. Some blockchain networks in order not

to favor the wealthier use randomization mecha-

nisms to choose the next node that will validate

the block (Zheng et al., 2018).

• Proof-of-Authority (PoA): This algorithm is

used in private blockchain networks. It is a con-

sensus where a set of authorities are responsible

for validating transactions, and to submit or create

a valid block, the person responsible for creating

the block requires the approval of all authorities

involved in this blockchain network (Miers et al.,

2019).

2.2 Animal Sanitary Control in

Reproduction Birds

Poultry health is a major concern and a high strate-

gic priority for poultry companies. Diseases are a

potential risk to livestock production in any coun-

try. The lack of sanitary control on farms can have

consequences such as (i) reduced productivity of lots,

(ii) total slaughter of birds, (iii) interdiction of farms

thus increasing the cost of production, loss of mar-

ket, among others. In Brazil, the Brazilian National

Poultry Health Program (Brazil, 2021) highlights that

the main objectives of the program are: (i) Prevent

and control diseases of interest in poultry and public

health, (ii) Deﬁne actions that enable the health certi-

ﬁcation of the national poultry stock, (iii) Encourage

the development of healthy poultry products for the

internal and external market;

Thus establishing the prevention, control and

surveillance measures of the main poultry diseases

that impact public and animal health, which are: (i)

Avian inﬂuenza, exotic in Brazil (never identiﬁed),

(ii) Newcastle disease, latest occurrences in 2006, (iii)

Salmonelosis (Gallinarum, Pullorum, Enteritidis and

Typhimurium), (iiii) Mycoplasmosis (Galliseptcum,

Synoviae and Meleagridis (turkeys)).

2.3 Plataforma de Defesa Sanit

aria

Animal do Rio Grande do Sul

(PDSA-RS)

The PDSA-RS platform aims to provide better in-

formation and process management and automation

for the existing animal health control process. It in-

tegrates agents from different areas, the integration

between the existing sectors characterizes a public-

private management model that brings improvements

to epidemiological surveillance. The PDSA-RS is

presented to users in ﬁve main portals: (i) Rio Grande

do Sul State Veterinary Service Portal (SVE), (ii)

Technical Responsible Portal (RTs), (iii) Agricultural

Laboratory Portal (Laboratory), (iv) Brazilian Min-

istry of Agriculture Portal (MAPA) and (v) Admin-

istration Portal (Admin);

The PDSA-RS follows the Brazilian epidemiolog-

ical surveillance standards and the National Poultry

Sanitation Program (Brazil, 2021).

2.4 Related Work

The section is dedicated to present related work with

this proposal. (Tripoli and Schmidhuber, 2018) pre-

sented a general idea in which the applicability of the

blockchain covers the process of the food and supply

chain as a whole, that is, from production on the farm

to sale to the ﬁnal consumer through the retailer. In

contrast, the research of this work covers only part

of the process, that of animal sanitary control, where

at the end of it, the establishment responsible for the

animals receives a sanitary certiﬁcate.

Towards a Blockchain Architecture for Animal Sanitary Control

307

The research (Makkar et al., 2020) states that the

attributes of blockchain technology make it ideal for a

number of applications in the animal production and

animal health sectors, sectors in which this work is

included in. Another work that is related is the re-

search (Feng et al., 2020). It proposes a sustain-

ability ﬂowchart for traceability systems based on

blockchains. Therefore being related to this research

because it is also about traceability of animal sanitary

control. The work (Vingerhouts et al., 2020) presents

a case study of software modeling for the ’traceabil-

ity’ of animals from birth to the arrival at the ﬁnal con-

sumer’s plate, identifying and keeping all the stages in

which the animal went through its life.

All the works identiﬁed are related to at least one

part in which this research has joined, but none has a

case study implemented in a real environment.

3 SOFTWARE ARCHITECTURE

DEFINITION FOR ANIMAL

SANITARY CONTROL

Blockchain technology has great potential to change

the existing workﬂow and processes (Ko

st’

al et al.,

2019). The animal health process can be part of this

change identiﬁed using Blockchain. Adding the in-

formation generated in the animal health process to

a Blockchain apparently becomes appropriate, as its

main characteristics support speed, accuracy, reliabil-

ity and immutability, requirements necessary to audit

information and generate reports.

3.1 Process of Blockchain Integration

The use of Blockchain technology for the animal san-

itary control process will not replace, for now, the

current process, but in the near future there are great

possibilities for this replacement, with the idea that

each process carried out to generate a certiﬁcate will

be recorded in the Blockchain, thus, available to ofﬁ-

cial agents and international authorities.

By making the process more transparent, eas-

ier and safer, bringing beneﬁts as in the case of an

outbreak of animal or plant disease, contaminated

animals can be tracked more quickly (Tripoli and

Schmidhuber, 2018). Figure 1 represents a simpli-

ﬁed blockchain system for animal sanitary control of

breeding birds, illustrates the process in the physi-

cal, digital ﬂow and how the data produced in this

process is stored in the Blockchain. The data is

stored block by block, generating a network of inter-

connected blocks, thus producing the beneﬁts men-

tioned above, such as traceability, immutability, trans-

parency and a history of the process.

Implementing Blockchain in the traceability of

records generated in animal sanitary control has great

potential, but it can be a challenge. Blockchain can

become slow according to the amount of data inserted

in it (Ko

st’

al et al., 2019), in the same way it will

require a complete reﬂection of the agents involved

in animal health, of how they approach the processes

and activities involved in the process.

3.2 Software Architecture Deﬁnition

The architecture deﬁnition of this research was based

on the existing software structure used for the PDSA-

RS process. Figure 2 illustrates the current PDSA-RS

architecture and the blockchain architecture incorpo-

rated in the platform. The architecture extension com-

ponents (presented in Figure 2) are described below:

Service (1) has certain rules and deﬁnitions so that the

information and access permissions are correct, so it

requests access (2) to the Blockchain management

API (3). Upon obtaining access, the service sends the

generated data to API (3), the data is then veriﬁed and

encrypted with the authority’s private key (4). After

this process, the authority (4) is asked to create a new

block to insert the information. For this creation re-

quest to occur, the Proof-of-Authority algorithm (5)

is executed, thus ending the ﬂow by inserting the data

into the Blockchain (6).

In Figure 2, the item (5) is marked with a red cir-

cle, representing that the algorithm is not currently

being implemented. In place of this algorithm for

carrying out implementation tests, we used Proof-of-

Work alghoritm. The following section will present

the case study of the scenario of the ﬁrst tests of the

proposed architecture, where some points were iden-

tiﬁed in the process in which the blockchain architec-

ture could act.

4 CASE STUDY

To evaluate the prototype that implements the theory

of this work, the sanitary control certiﬁcation process

of poultry establishments in the state of Rio Grande

do Sul was mapped, an animal health process for

breeding birds.

4.1 Case Study Deﬁnition

The process was mapped using the Business Process

Model and Notation (BPMN), thus obtaining the cen-

tral points where the architecture proposed by the

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Figure 1: Simpliﬁed view of Blockchain application in animal health for breeding birds.

Figure 2: Existing / preliminary architectural overview.

work would act. With the mapping it was deﬁned

which data to store and at what time to store, as the

mapped process was very large, it was divided in two,

represented in Figures 3 and 4. Therefore, the points

identiﬁed to store the generated data were, respec-

tively: (i) Data ﬁlled in the harvest form, (ii) Data

contained in the report issued by the agricultural lab-

oratory, (iii) Certiﬁcate (information processed from

raw data from previous steps);

With this data set collected, a health certiﬁcate is

issued. And each step is contained in a block of the

Blockchain. The next section will describe the pro-

totype implemented to perform the insertion of steps

1,2 and 3.

4.2 Application and Discussion

After the mapping process, we prototyped the soft-

ware architecture to integrate blockchain in PDSA-

RS. In the prototype, the information generated in

the steps mentioned above 1, 2 and 3 were inserted

in the Blockchain of the same. With the use of this

prototype, it was identiﬁed that the data recovery

started to become increasingly slower as the block

chain increased. For this reason a log schema was

implemented in a relational database, this strategy

is to supply the need for information consumption

by the end user, where all information stored in this

schema is inserted into the blockchain. Therefore, en-

suring security, immutability and auditability of the

blockchain and the speed and scalability of the rela-

tional database.

Another strategy adopted was to reduce the num-

ber of blocks generated, where each step of the pro-

cess was transformed into a block, generating a quan-

tity of 3 blocks for each certiﬁcate issued. To re-

duce this amount, it was adopted that each step of the

process is a transaction, where at the end we have 3

transactions: (i) data from the harvest forms, (ii) data

from the reports and (iii) data processed from the pre-

Towards a Blockchain Architecture for Animal Sanitary Control

309

Figure 3: Process to obtain a sanitary report on the moment of life of a poultry batch.

Figure 4: Process to obtain a health certiﬁcate from the nucleus of a poultry establishment.

vious steps, contained in a single block, facilitating

auditability, forming a certiﬁcate and reducing from

3 blocks to 1, a signiﬁcant 66.66% reduction in the

block size. The block is created using the Proof-of-

Authority algorithm. Finally, a smart contract was de-

veloped to ensure that transactions actually meet the

necessary speciﬁcations, in other words, if you really

have all the information (data) needed to issue a cer-

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Figure 5: Sequence diagram of certiﬁcation process in PDSA-RS with the Blockchain extension.

tiﬁcate. However the recovery of the data contained

in the blockchain has been recovered consistently, en-

suring a reliable history of the data of the health cer-

tiﬁcation process of poultry establishments.

Figure 5 represents a simpliﬁed sequence diagram

that wraps Figure 4, 5 and adds blockchain func-

tionality. From activity 5.1.1 of the sequence di-

agram, blockchain functionality begins to emerge:

5.1.1 Smart Contracts, when analyzing the data and

issuing the certiﬁcate via the platform, the smart con-

tracts are triggered verifying that all the data neces-

sary for the certiﬁcate to be sent to the blockchain

were provided by the PDSA-RS platform. Once veri-

ﬁed, they are sent to the blockchain (5.1.2).

The following code is a small example of a code

snippet from a smart contract for Ethereum, using the

Solidity, high-level object-oriented programming lan-

guage designed to implement Smart Contracts (Dan-

nen, 2017), used to validate the data mentioned in step

5.1.1, in which it is triggered when a certiﬁcate is is-

sued via the platform. After the end of the contract

execution, the data are sent to the blockchain.

pragma solidity >=0.4.0 <0.6.0;

contract ValidadeData {

// Simplified structure of a Certificate

struct Certificate {

string harvest_term;

string age_birds;

string protocol;

uint lot_number;

string responsible_harvest;

}

Certificate c;

function validade() public {

// business rules

}

5.1.2.1 Encrypts the data, the data when sent is en-

crypted to be inserted into the blockchain block. 6

Consensus algorithm, while the data is encrypted, the

consensus algorithm is called, creating a new block

(6.1). Then the data is written to the block (6.1.1) and

thus remains available and immutable forever. After

this action, the blockchain returns a successful trans-

action response and the platform provides the certiﬁ-

cate to the requester (7, 7.1, 7.1.1).

5 CONCLUSIONS

We know that blockchain technology is on the rise,

not just in the ﬁnancial or cryptocurrency area, where

it has become popular, but in other areas. This work

described the main characteristics of a blockchain, ex-

plaining its architecture and functioning and its con-

sensus algorithms. Demonstrated how it can be ap-

plied to the traceability of animal sanitary records

because of its characteristics, an immutable ledger,

where you have the entire process in a safe way and

Towards a Blockchain Architecture for Animal Sanitary Control

311

complete like this improving the management and au-

ditability of the records, making it transparent to the

ofﬁcial bodies involved. A case study mapped with

BPMN of the health certiﬁcation of poultry establish-

ments in the state of Rio Grande do Sul for breeding

birds was presented. Mapping that made it possible

to apply the knowledge acquired for the implemen-

tation of a blockchain integration prototype with the

already existing PDSA-RS platform, with the objec-

tive of storing the data generated in the certiﬁcation to

obtain traceability and auditability of high conﬁdence

and of added value.

Therefore, the prototype fulﬁlled its objective by

bringing to the certiﬁcation process the beneﬁts that a

blockchain provides us, such as transparency, agility,

immutability, security and reliability, but at the same

time, it brought us a problem of poor performance

when recovering data according to blockchain size

increase. The problem was solved with a change in

how to insert the data in the blockchain and with a log

schema implemented in a relational database, witch

gives better data recover performance and query ca-

pabilities, uniting the beneﬁts of both (blockchain and

database).

Future works envisaged so far are: (i) Compare

performance and beneﬁts of different blockchains im-

plementations, like Ethereum and Hyperldger, in the

context of private blockchains, (ii) Develop more

Smart Contracts, to automate more parts of the pro-

cess and make it more and more intelligent, (iii) Im-

prove Smart Contract performance and correctness

and (iiii) Identify and map similar processes with the

potential for implementing blockchains.

ACKNOWLEDGEMENTS

This work is part of ”Research and Development of

Innovative Technologies Focused on Agribusiness”

(n. 051568) and is ﬁnanced by FUNDESA.

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