Indigenous pigs are essential domestic animals for rural
life and meat supply in Laos, especially for ethnic people in remote areas.
Northern provinces have the most numerous indigenous pig populations, i.e.
covering 84 % of the total pig population. This study was conducted in
northern Laos, where 164 pig-raising households, 325 sows and 1246 piglets
were included. The study aimed to observe the general trend of change in
indigenous pig utilization and the altered reproductive performance
regarding village location and rearing systems. The semi-structured
questionnaires were a key tool for gathering data required through personal
interviews and field observations. Two types of indigenous Lao pig breeds
(locally named Moo Lath and Moo Hmong) were found in study areas. The village locations were
not influencing on reproductive performance of indigenous Lao pigs. Larger
litter size and birth weight (
Indigenous pig breeds are still dominant in Laos, which covered more than 91 % of the total pig population (3.1 million) in 2014. Most of them were
raised by smallholder farmers, in particular, in rural or mountainous areas
(Keonouchanh, 2018). Indigenous pigs not only contributed to meat consumption
and primary income for households (Holt et al., 2019; Okello, 2017), but also
they were also important to the traditional activity performance of
farmers, especially ethnic people living in remote areas of Laos (Keonouchanh et
al., 2014). In a similar report of Xayalath et al. (2020), indigenous pigs play
an important role in the supply of meat and contribute between 9 %–14 %
of the annual household income in the rural areas of Laos. It could be said
that the ethnic people (Lao-Tai, Mon-Khmer, Hmong-Mien,
Tibeto-Berman) living in the mountainous areas of Laos, especially in the
north, could not abandon indigenous pig raising (Phengsavanh et
al., 2011). In 2019, Laos counted a pig population of about 4.1 million,
including 1.4 million in the north, 1.2 million in the central region, and 1.5
million in the south (MAF, 2020). Lao government has been active in
encouraging farmers to move from conventional production to farming
production, which could both control quality and increase pork production to
meet pork consumers' needs (MAF, 2015). However, the southern part had the
largest number of pigs (with more commercial pig farms). Still, the northern
region also had the second largest pig population with an enormous number of
indigenous pigs, almost 85 % of the total pig population. In northern
Laos, more than 60 % or some areas (Phongsaly Province), more than 90 %
of the total households owned at least one indigenous pig (Epprech et al.,
2018). Unfortunately, since 2016, not only in Laos, the number of indigenous
pigs has decreased. Because of the African
swine fever (ASF) disease and other factors, it
has rapidly declined in all Association of Southeast Asian Nations (ASEAN) countries as well. However, indigenous
pigs produce delicious and healthy pork, and the new market options should be
found for the survival of these breeds and for the poverty alleviation in
rural areas. Indigenous pig production in Laos is facing two main chronic
problems: sows give a small number of piglets per litter and poor farm
management, causing various negative impacts on pig performance. This includes only about
5–8 piglets per litter with a few survival piglets at the time of weaning
(mortality rate 20; 50 %) and poor growth rate (Chittavong et al., 2012;
Phengsavanh et al., 2010) with an average daily gain less than 120
We need to find out all the holes in the development of indigenous pigs and find the options of the better practices of Hungarian Mangalica pig farms in Hungary, to be complied with and adopted or recommended to improve the quality of indigenous pig performance for farmers in Laos. This study was conducted with two main objectives. The first was to study the general trend of the indigenous pig population and compare the reproductive performance of indigenous pigs based on clustering villages and rearing systems. We also indicated two hypotheses that indigenous pigs raised by farmers who live near downtown would have better reproductive performance parameters than those raised by farmers who live far away from downtown because of easier access to feedstuffs and other facilities. Another hypothesis was that the indigenous sows raised in the confinement rearing system would have better reproductive performance parameters than the other two raising systems (free-scavenge and semi-scavenge rearing systems), as farmers would provide them with better feedstuffs and other practices.
Map of the survey area; Epprecht et al. (2018), CC BY 4.0.
This study was conducted in northern provinces of Laos, where there were densely populated indigenous pig-raising households. This involved about 60 % to 90 % of the whole households engaged in indigenous pig farming in the region (Epprecht et al., 2018, CC BY 4.0; Fig. 1). This region is a mountainous area, home to different ethnic groups such as Lao-Tai, Mon-Khmer, Hmong-Mien, and Tibeto-Berman (Messerli et al., 2008), who consider indigenous pigs part of their livelihood. In northern provinces, most pig raising was based on traditional systems such as simple confinement, free scavenging, and semi-scavenging. Most farmers fed their pigs based on feed produced from agricultural production, i.e. maize, cassava, rice brand, and forest vegetation (Phengsavanh et al., 2010).
Five provinces (Phongsaly, Oudomxay, Xayaboury, Louangprbang, and Houaphanh) out of seven provinces in northern Laos were selected to participate. Phongsaly had the highest number of pig-raising households, ranging about 80 %–91 %. While other provinces had between 60 % and 80 % (Epprecht et al., 2018, CC BY 4.0; Fig. 1). One or two districts were selected from each province. Each district selected one to three villages to represent the survey, based on discussion with each livestock unit of DAFO (District agriculture and forestry office). Out of 8 districts, 164 families of pig-raising households were selected to participate in the survey covering 325 sows and 1246 piglets. A household with at least one indigenous sow with one farrowing experience, and who volunteered to respond to the questions, was considered to qualify for the sampling.
The semi-structured questionnaires were a pivotal tool to collect primary
data from pig-raising households based on individual interviews. The pig
population's statistics for the last 5 years were collected through the
livestock section of each PAFO (province agriculture and forestry office) of
all northern provinces of Laos. These data were used to analyse the indigenous
pig population trend in northern provinces of Laos (Table 1). The general
pig production data were discussed with the respective DAFO livestock unit
team of each selected district. The personal interviews using the prepared
semi-structured questionnaires were carried out to obtain the primary data
of the reproductive performance of indigenous sows. In order to get
different data on reproductive performance parameters, raising system,
managements, problems, and causes of piglet mortality, the target villages
were classified into three clusters based on
The collected data were entered into Microsoft Excel version 2010 and stored
before analysis. Descriptive statistics were used for pig population trends
presented by graphs and bar charts, including the percentages and
differences in breeding management, farrowing management, and the causes of
piglet death. These data were analysed using Microsoft Excel 2010. One-way ANOVA
and Tukey's post hoc test of the SPSS statistic version 26 (2019) was used
to check for the significant differences in the mean values of reproductive
performance parameters, in particular age of obtained puberty, age of first
mating, litter size, birth weight, suckling period, weaning weight, the
mortality of piglets, and the lifespan of sows and boars. The significant level
of 0.05 (
However, the indigenous pig population's overall trend in the study areas was a decline from 2015. Still, at the time of the study, the indigenous pig population in northern provinces of Laos was high at 84.5 %. Table 1 showed that the percentage of indigenous pig population was consecutively decreased from 93.51 % in 2016 to 84.57 % in 2019. Regarding the livestock section of each PAFO reported, there were some new investments on commercial pig farms of Chinese companies in larger provinces in the north of Laos such as Louangnamtha, Oudomxay, and Louangprang from the second half of 2016. In addition, all PAFOs and DAFOs reported that ASF was an epidemic disease that killed a large number of indigenous pigs raised by small-scale farmers in the north of Laos. It might be a result of the indigenous pig population decreasing by almost 5 % on average in 2019 compared to 2018. Some provinces such as Oudomxay declined by almost 15 %, and Louangprabang Province was around 7 % on average (Table 1).
The trend of indigenous pig population in northern Laos from 2015–2019 (thousand heads).
TPP: total pig population; NPP: native pig population; %: percentage of native pig population; PhP: Phongsaly Province; LNP: Louangnamtha Province; OP: Oudomxay Province; BP: Bokeo Province; LPP: Louangprabang Province; HP: Houaphanh Province; XP: Xayaboury Province; GT: grand total of pig population.
The average age for obtaining puberty of indigenous gilts
was around
Indigenous pig reproductive and productive cycle. AFM: age of first mating (month).
There are significant differences in several reproductive performance
parameters based on villages' cluster locations and rearing systems (Tables 2
and 3). In particular, the second cluster (
Comparison on reproductive performance of indigenous pigs based on village locations.
The free-scavenging rearing system (FRS) had a larger litter size, birth
weight, weaning weight, and longer lifespan of sows (Table 3) than the other
two rearing stems. There was a difference (
Comparison of the reproductive performance of indigenous pigs based on rearing systems.
The piglets' average mortality rate before weaning was around 15.45 % and
did not differ between village locations or rearing systems (
Comparison of piglet mortality based on village clusters and rearing systems.
Table 4 shows the age of puberty estimated strongly positively correlated to the age of first mating and the age of first farrowing. In contrast, litter per year and birth weight are highly negatively correlated with suckling period and weaning weight.
Correlation coefficients among reproductive traits of indigenous pigs in northern Laos.
In the study areas, indigenous pig production was mainly based on traditional rearing systems such as simple confinement, free scavenging, and semi-scavenging and found to be around 39 %, 25 %, and 36 %, respectively. The pig rearing systems depended on the seasons of agricultural production and the village regulations. Most of the villages in the study areas are now striving hard to build and lead their villages to meet the criteria of becoming a sanitized and developed village, with respect to three constructive levels of national development strategy (Central committee party office, 2012). Keeping animals in pens, especially pigs, is also one of the criteria that every village has to consider and follow as a wide-range regulation in many areas. Pig raising as a semi-scavenging rearing system usually comes in two forms. In the first form, farmers kept their pigs in pens only in the night-time after they fed them in the evening. During the daytime and otherwise, they would keep their pigs in pens only during the main crop production season and leave them in free-scavenging mode again after harvest. This is very similar to earlier Hungarian farmers in the villages who kept their Mangalica pigs indoors only in the night-time, and they grazed all their pigs in the communal pasture (Egerszegi et al., 2018).
Pig housing, nutrition condition, and proper selection of both gilts and boars are three main issues to consider for improving indigenous Lao pig breeds' current productive and reproductive performance in northern Laos. Egerszegi et al. (2018) summarized the past and current status of Hungarian Mangalica pig with special regard to breeding and reproductive performance research: (1) select replacement gilts, large litter, and at least 10 functional teats; (2) stimulate gilts and weaned sows to come into heat at a similar time and get piglets in the same batch; (3) improve housing and nutrition in case of intensive breeding; and (4) improve feeding of sows bred intensively and culling after sows have achieved her six–seventh farrowing. These successful development tracts should be introduced to improve the quality of indigenous Lao pigs.
Two different types of local pig breeds – i.e. Moo Lath and Moo Hmong – were found in the study
areas. These two types were commonly found in northern Laos. These two
breeds were different in the growth rate and reproductive performance,
especially litter size of 7–8 versus 7–10 (Keonouchanh et al., 2011).
However, no evidence on genetic information was found that described the
difference between these two types of pig breeds, but their phenotypes were
so different among them (Wilson, 2007). Due to the differences between types
of breeds, this may be one way of explaining the difference in litter size
and birth weight (Gokuldas et al., 2015). It was found that there was
no difference between FC (
This study's findings may also differ from other theories and research where it was found that many parameters of indigenous pig reproductive performance in the free scavenging were better than the confinement and semi-scavenging rearing systems, especially the litter size, birth weight, and weaning weight. It might be hard to explain with the right reason; again it could be assumed that feeding and scavenging could be one option to consider what made them different. There was no difference in feeding among the three different rearing groups. Farmers always fed their pigs once in the morning and another once in the evening with available local feed resources such as cassava roots, rice bran, and kitchen waste produced from agricultural production (Huynh et al., 2006). Due to the smallholders, farmers could not buy high-quality feedstuffs or completed feed for their pigs (Stur et al., 2002). The pigs in the free-scavenge rearing system were able to consume, including scavenging, and were fed by their owners in the morning and evening.
Almost 51 % of farmers reported that their sows gave birth during the
main agricultural production season between June and September. Around 24 % gave birth to the piglets after the harvesting season between October
and December and about 25 % during the non-agricultural production
season. For most wild boars and earliers Hungarian Mangalica pigs the heat and
mating occurred in the autumn and farrowing 4 months later in the
spring, and sometimes a second farrowing might have again in August and
September (Webster, 2011; Egerszegi et al., 2003, 2018).
It is also hard to accurately describe the difference (
The mortality rate (15.45 %) was lower than the study of Phengsavanh et al. (2010) with around 50 %, which was carried out in the same region, and the study of Chittavong et al. (2012) with around 20 %, which was conducted in the central provinces of Laos. It could be considered that the piglet mortality might be high for the early weaning due to new transit and improper feeding by farmers. Based on the early weaning period, one of the key aspects to consider for the piglet survival and growth rate is that new transit could increase more stress, and new feed could be harmful to the new transit piglets (Campbell et al., 2013). It was interesting to note that this study found that the FRS had the lowest piglet mortality rate (13 %), compared to CRS (15.91 %) and SRS (16.93 %). The statistics are presented in Fig. 3. It was hypothesized that some farmers might lose the monitoring of their sows for the first three days after farrowing. All households from the FRS group responded that they left their sows to give birth in the nearby forest. Some of them did not even know that their sows had already given birth to the piglets until the sows brought their piglets back home. Again, it was assumed that farmers might not know how many piglets had died before they had been found. Before weaning, most piglet mortality always occurred during the first three days after farrowing, due to weakness, lack of immunity, and the fact that piglets can be easily crushed by their mother (Deviller et al., 2011).
However, the population of indigenous pigs has decreased year by year due to Lao consumers' eating preferences. They increasingly prefer lean (low fat) pork that is provided by exotic pig breeds rather than fatty pork that is characteristic of indigenous Lao pig breeds. Still, indigenous pigs are a key component of meat consumption in Laos. Most farmers raise their pigs mainly under traditional practices, so proximity to downtown or facility services is not crucial for reproductive performance of indigenous Lao pig breeds. In general, the pig rearing systems also do not affect the reproductive performance of indigenous Lao pigs. This study showed that the free-scavenging rearing system had a marginally better litter size and birth weight and had the lowest piglet mortality rate compared with confinement and semi-scavenging rearing systems. Most previous research stated that the free-scavenging rearing system was poor in every parameter of productive and reproductive performance of indigenous pigs compared with other rearing systems. The local community services (e.g. providing feedstuff) and rearing systems have no strong influence on the farmers with special regards to reproductive performance of indigenous Lao pigs. However, proper farm management might have a major impact on overall productivity. Actually, most Lao farmers still raise their indigenous pigs in a traditional extensive system and do not operate their farms in a business manner. Therefore, the combination of the extensive and intensive model of Hungarian Mangalica pig breeding and production system might be a positive option to introduce and adapt to improve indigenous Lao pig performance. Based on the present study, we can conclude that Lao farmers might be able to improve housing and feeding methods and to develop relevant reproductive management of indigenous pigs with the goal of increasing the number of surviving market-weight offspring.
The data sets are available upon request from the corresponding author.
SX and JR conducted the study and designed the research included preparing the manuscript. GND and KPB helped provide advice on technical aspects and helped to revise the manuscript. PB participated in improving research questions and questionnaires and helped with data interpretation. All authors read and contributed individual feedback before approval of the final version of the manuscript.
The authors declare that they have no conflict of interest.
Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
The authors acknowledge the whole corning team from the district agriculture and forestry office (DAFO) and province agriculture and forestry office (PAFO), as well as Dongkhamxang Agriculture Technical College (DATS), who contributed to the collection of data. Similarly, the authors also acknowledge the pig farmers, who provided all beneficial information in this study.
This work was supported by the Tempus Public Foundation in the framework of the Stipendium Hungaricum Programme.
This paper was edited by Manfred Mielenz and reviewed by Miroslav Rozkot and one anonymous referee.