A survey on milk production and management on smallholder farms in Hochiminh City, Vietnam
 

Nguyen The Thao, Vo Lam and Ngo Van Man^*
 

Department of Animal Husbandry and Veterinary Sciences,
Angiang University, Angiang Province, Vietnam

ntthao@agu.edu.vn

^* Department of Animal Nutrition, Nong Lam University, Ho Chi Minh City, Vietnam

Abstract

The study was carried out in the peri-urban areas of Hochiminh City, which is located in the South of Vietnam. The objective of the survey was to understand the setting of the dairy production and management in smallholder dairy farms. Data on milk production and management were obtained by using a 120-question structured questionnaire and field observations from 120 smallholder dairy farms in two districts of Hochiminh City.

There a great variation in experience of dairy production, with 60.8% having experience of from 10-20 years.  Almost all of the farmers (79%) adopted the techniques from the training on dairy production provided by the extension centers in the districts. The dairy activities of the farms were managed by their own family labors, with an average of 5 people per farm. The average herd size was 12 (ranging from 2 to 17 head), and milking cows were the highest proportion of herd structure (6 cows per household). The main breeds of dairy cattle in the farms were Holstein-Friesian (95.8%), and 4.2% crossbred Sindhi. The farmers used Napier grass, natural grasses, brewery by-products, cassava waste and commercial concentrates for feeding their dairy cows. The amount of feeds given satisfied nutrient requirements, but the concentrate proportion (52:47, concentrate: roughage ratio) was high. The success of artificial insemination (AI) was low, 43.4 % of milking cows for 5-7 time s/ pregnancy.

The findings of the survey show that the milk yield of this breed is high (15.98 kg/day/cow), and fat, protein, lactose, dry matter, solid non-fat  were 4.1%, 3.2%, 4.7%, 12.6 and 8.6%, respectively, and were acceptable.

Key words: AI, breeds, calf rearing, Holstein-Friesian, interview, mastitis,  questionnaire, Sindhi, suckling

Introduction

 Smallholder dairy production systems are potentially very important for the food production of animal origin in developing countries. Their importance is expressed by the government support to this sector in many countries,  due to excessive imports of milk and milk products, and more importantly, because of the recognition of the influence of dairy on income generation, tangible economic benefits, household nutrition and poverty reduction (Devendra 2001).

Dairy production in Vietnam has been strongly promoted by the government since October 2001, with the aims of replacing imported milk, and generating rural employment and incomes. To achieve these goals, the dairy cattle herd is expected to increase from 38,000 heads in 2001 to 100,000 heads and 200,000 heads in 2005 and 2010, respectively (MARD 2006). Currently, according to government statistical data, 95% of the dairy cow herd is raised in backyard/household farms, with an average number of 4-5 dairy cows per farm (in the North) and 7-10 cows per farm (in the South).  Only 5% of the national herd is in what are considered commercial operations with a thousand cows or more, and the largest populations are in the provinces of Hochiminh City (56,162 head) (MARD 2006).

Hochiminh City is one of the target areas of the National Dairy Development program. From 25,089 heads  and a total milk production of 44,218 ton per year in 2000 the dairy herd increased to 56,162 head and 129,000 tons of milk were produced in 2005 (DARDH 2006), while the whole dairy herd of the country was 107,609 and total milk production is 197,700 tons (Thuong et al 2006). In this area, there are many strategies to develop dairy production, in improving milk marketing, veterinary, extension services and dairy cattle feed resources. Fresh milk can be sold easily to customers or to the processing factories, which are located in Hochiminh City and Binh Duong Province (30 km from Hochiminh City). Abundant industrial by-products (such as brewery byproduct, cassava wastes, soybean residues and molasses etc) are available in this area, and can be used for feeding dairy cows, and a strong  system of veterinary and extension services has been developed up to district level for technical transfer and veterinary services.

However, the dairy production is still rather new to the farm sector in Vietnam, and the farmers have very little practical experience of production systems and management. Due to the pressure of urbanization and environmental considerations, the dairy herds had to move to the suburbs, where the farmers have rather little experience and capital and in addition to the problem of shortage of land, and roughage, there is the high price of mixed feed (Khang 1999).

The survey was carried out in order to obtain information on the situation of dairy production in the smallholder dairy farms in Hochiminh City, Vietnam.     

Materials and methods

Site selection and description

The survey was carried out in the area around Ho Chi Minh City, which is located in the South of Vietnam. This area accounts for 54% of the total dairy cattle of Vietnam. The individual farms participating in the survey were spread out in two districts, Cu Chi and District Number 12. The main agricultural activities in these districts are rice, cash crops and dairy cattle, and there are at least 1,000 dairy farms within each district. Dairy cows are mainly kept in smallholder systems that have 2 to 50 cows per farm and mostly managed by family labor. Green grasses from backyards or fields and agricultural crop-residues such as rice straw, bean vines etc. are used as the main roughages. Beer distiller by-products, cassava wastes and commercial concentrates are used as supplement feed.

Selection of studied farms

The secondary data on socio-economic aspects, dairy production and maps of the districts were collected and used in the first processing and evaluation of the research sites. The visit to district and village offices before the survey started was to understand the dairy production of the district from the corresponding local authorities and groups of farmers.  Sixty smallholder dairy farms were randomly selected within each district. Sampling was then done by withdrawing farms from the list of all dairy farmers by matching with a series of randomized numbers generated from Microsoft Excel worksheet. A total of 120 farms is representative of approximately 6% of the total number of small-scale dairy farms, based on census records of the two districts.

Questionnaire and interview

Questionnaire for direct interviews and a checklist for observations were designed to obtain basic information about milk production and management of household farms. Ninety questions related to information about household, breeds and breeding, feeding and management systems, milk production capacity, milking routines and management, and calve rearing were included in the questionnaire form. Checklists for observation were used to check farm conditions in practice at the studied farms regarding animal health, hygiene, feed and water, milking routines and practices.

Before the survey started all questions in the questionnaire form were pre-tested in the field, modified and clarified for later official interviews with the farmers. In practice, interviewers took the interview with the respondents, who were representative for the household and well understood their dairy production. The duration of each interview was at least 3 hours. The interviewers asked for an additional visit to the farm for observation or for any necessary measurements and an appointment with the farmer, and collection of milk samples for analyses of milk composition.

Milk sampling and analysis

Milk samples were taken from individual cows randomly, which corresponded to at least 20 percent of cows per herd at the studied farms. Milk samples were analyzed for dry matter, fat, protein, lactose, solid non-fat by a mid infrared spectroscopy method (Farm Milk Analyzer, Miris AB, Uppsala, Sweden).

Feed sampling and chemical analysis

Feed samples were taken from the studied farms. The samples of brewery residues, cassava waste, concentrates, Napier grasses, rice straws and natural grasses were analysed for dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) at the animal nutrition laboratory, Angiang University. The DM and CP were determined according to AOAC (1990). CP content was analyzed by the Kjeldahl method as Total N* 6.25. The contents of NDF and ADF were determined according to Van Soest and Robertson (1991).

Data management and statistical analysis

Collected data of the questionnaires were checked and transferred into the same unit of measurement. The quality variables were coded into categorical values. Collected data were then entered into worksheets of Microsoft Excel 2003 (Microsoft Corporation, copyright © 1985-2003). The statistical analyses were performed using SPSS for Windows version 14.02 (SPSS Inc., copyright © 1989-2005). Descriptive statistics with mean, median, frequencies, max, min, and range were used. The independent-samples T-test procedure was used to compare the means of the quantitative variables, and to test if there were any significant differences (p<0.05) between the sites. Pearson’s correlation was used for chi-squared statistics evaluation for categorical variables.

Results

Characteristics of dairy farms

One hundred and twenty farmers answered the questionnaires. This represents 6% of all smallholder dairy farms in the two districts. The results showed wide variation in experience in dairying farming, that varied from 2 to 30 years. However, 60.8% of the farmers had experience of from 10-20 years. Most of the farmers (77.8%) had started their dairy production by use of family capital, 6.7% with capital from the banks (agricultural or commercial bank), 15% with capital from their relatives or donation, and 5% got their capital from micro credits of local organizations. There were three main dairy-based systems in the area: dairy only, dairy and crops, and dairy and other animals. Most of the systems (77.5%) had dairy only, 20% dairy and crops, and 2.5 % dairy and other animals. Most of the farmers in both districts started their dairy farming some years before or after 1990, with crossbred Sindhi and F1 cows (crossbred Holsteins).

Age and education of respondents

Table 1 describes the structure of the farms. The main activities on the farms were managed by laborers from 20 to 60 years old. For dairy production management, the respondents of the survey were responsible for most of the activities (81%), whereas other members of the family managed the dairy activities only in 19% of farms. The average age of respondents was 45 years, with 11 years of experience in dairy farming. For the education of respondents or heads of the dairy farms, 41.7% had elementary school, 35.8% primary high school, 20% high school, 0.8% vocational schools and 1.6% had studied at college or university.  Almost all of the dairy farm owners (90.8%) were farmers, while 9.2% were local officials, teachers and retailers. There was no statistical correlation between education and farm size, number of cows, and milk yield. Most of the farmers (79.2%) attended training programs on dairy production, whereas, 20.8% did not attended any training. They operated their farm production by learning from their neighbors or self-experience. There was no correlation between training and farm size, milk yield and milk quality.

Land holding and use

On average, the dairy farm owners hold 4,832 m². The average land sizes for pasture, cropping and animal house were 3,322m2, 2,162m², and 208m², respectively; the animal houses were set up in the backyard near the farmer’s houses (Table 2).

There were 72.4% and 10% of the dairy farmers who did not have any land for pasture or for crops, respectively. There was a significant correlation between land size holding and herd size (r (120) =0.29, p=0.001), years of experience and herd size (r (120) = 0.33, p=0.001).

Herd structure and herd management

There was a wide variation in the herd size, and farmers kept from 2 to 50 cows. The majority of the studied households owned between 2 to 17 cattle (mean = 12). The number of milking cows was the highest part in the in herd structure (Table 3). The main breeds of dairy cattle used in the farms were HF (95.8%) and crossbred Sindhi (4.2%).

According to the results of the survey, almost the dairy cattle were kept in the cow house. Cut and carry was common in this area. Fifty-nine percent of dairy farmers reported that milking cows suffered from heat stress during the onset of the dry season, whereas the figures were 40% for dry cows and less than 12 percent for heifers. A higher number of farmers (83.4%) reported that milking cows were sensitive to increase in temperature during periods of sunshine (83.4%). By observation, almost all of the farmers did not apply any cooling system to control temperature and the micro-environment of the dairy barn. The most common way to solve that problem was to water the dairy cattle at noon.

Milking routines and management       

All of the cows were milked twice per day, in the early morning (04.00 - 0600h) and at 16.00 to 17.00h. The most common method was hand milking (91.6%) and only 9.4% by machine milking (table 4). Udder cleaning with water was done before and after milking. In the case of mastitis occurrence dipping the teats in anti-germ solution was applied. Forty-four percent of the dairy farmers employed laborers for milking, whereas the others (56.4%) managed by using their family labor. There were no statistical correlations between milk yield and hand milking or machine milking or family labor and hired labor.

The labor cost for milking was five hundred VND per 1 kg of milk. Hiring labor for milking is common in this area, especially in the newer dairy farms, in which farmers lack knowledge and skill in milking, and in these cases they sell some milk directly to the hired milker.  

Reproduction capacity

Table 5 shows the number of AI services for conception of heifers and milking cows. The percentage of milking cows getting pregnant with AI services of 3- 4 times and 5-7 times was 47.5% and 43.4 %, respectively. Otherwise nearly 100% of the heifers conceived after 1-2 AI services.  Usually, farmers sold their cows if they failed with AI more than 7 times.

In total 71.4 % of farmers kept record books for simple facts of production such as disease prevention, calving and breeding. The recording for milk was managed by the milk collection centers and therefore no exact data was available for individual cows, only information directly made by the respondents of the questionnaires collected.

Considering calf rearing methods, 79% of dairy farms applied bucket feeding and 21% used restricted suckling. However, there was no significant difference between the methods of calf rearing with respect to the milk yield and milk quality. Ninety-percent of the farmers reported that saleable milk yield increased if the calves were raised by artificial rearing methods, but there was no evidence from the results of the survey.

Feed resources and feed utilization

The chemical composition of roughages, industrial by-products and commercial concentrates is shown in Table 6. The mean contents of CP, EE, NDF, ADF and Ash in Napier grass and natural grasses were almost identical. The concentrates played an important role as protein and energy supplements due to their high CP content (17%). Cassava waste had very poor nutritional values compared with other feed sources, while brewery byproduct had a high CP content (25.87%).

Farmers used green grasses from the fallow land, backyard or from pasture land for feeding their lactating cows, and fed from 20 to 40 kg of green grass per cow per day, depending on the availability of grasses and rice straw, stage of lactation and amount of commercial concentrates. Eighty eight percent of farmers feed from 3 to 6 kg of rice straw to their cattle. Industrial by-products (brewery residues and cassava waste) were fed in all of the households with a mean amount of 2.7 kg DM (Table 7). The estimation of commercial concentrates for feeding milking cows was from 4 to 6 kg per day. Industrial byproducts and concentrates were mixed with water and fed to the dairy cows twice per day. The farmers adjusted the proportion of feeds according to the daily milk yield of the cow, and in the milking cow diet the mean proportions of roughages, byproduct and concentrate were 47%, 17% and 36%, respectively (Table 7). The feed residues from the troughs were removed and water was added to give the cows free access throughout the day. In our observation, 45% of drinking water troughs were not clean enough, and this often made the cows reluctant to drink. There was no statistical correlation between water supply and heat stress status and milk yield.

Milk yield and quality

According to the data in the questionnaires, the average milk yield was 15.93 kg/day, and there was no significant difference between the districts. The average contents of fat, protein, lactose, dry matter, and solid non-fat were 4.1%, 3.2%, 4.7%, 12.6% and 8.6%, respectively (Table 8). Milk yield and milk quality did not correlate with milking method (hand milking or machine milking), hand milking routines (full hand and thumb in), herd size (large, medium and small size) and number of years of experience of the farm owners. 

Discussion

Smallholder dairy farms

Dairy cows in the south of Vietnam were introduced into the traditional farming systems in 1989, when the demand of the domestic market increased  (Tam 2004). The dairy production in the area had mainly been started in the districts near to the central of the city and was on a backyard scale, with a small number of milking cows per household, and only a few large scale, modern dairy farms (i.e. more than 100 cows per farm) had been established in the peri-urban areas of Hochiminh City and its vicinity. In the present study, the situation of dairy production related in respect to farm conditions (Table 1, 2) was nearly the same as in Thailand in last decade, as reported by Chantalakhana and Skunmun (2002). Smallholders tend to gradually increase the number of cows in their farms from 2 to 17, according to their management capacity (Falvey and Chantalakhana 2001), and access to and cost of green grasses and commercial concentrates. The fact is that the dairy production in the studied area depends on the price of commercial concentrates and the salable milk price and these factors exert a strong effect on the herd size per household. The fast development in dairy production in this area is based on a good market (milk price and milk collection), low cost of feeds and labor, and comparative high productivity compared to other agricultural enterprises (Tam 2004).

The variation observed in the years of experience in dairy production is an indication of the development of dairy production in the research area. Land competition from urbanization is very high and has forced dairy producers to move farther away from the city. As a result of this situation the number of dairy farms has increased, and land holding and herd size decreased. Where dairying is an integral part of the farming system, more farm households involved in the production resulted in increasing cattle population. Consequently area pasture land was reduced and there was a shortage of grass for dairy cattle. Labor need is an important factor in dairy production, but at this time it seems not to be a big problem, due to the small scale of the production, so the majority of farm work can be done by the family.

Cows and managemen

The herd structure per household in Table 3 shows that the mean percentage of milking cows in the herd is similar to data reported in Thailand (50.6%; Chantalakhana and Skunmun 2002). Milking cows in smallholder farms are to generate cash for reinvestment to continue production (Mutukumira et al 1996 and Lanyasuna et al 2006) and for family expenses. In response to the question on what part of the herd should be increased in the future, 94.6% of the farmers answered that would like to increase the number of milking cows in order to increase salable milk. Heifers were used to replace milking cows or to expand the herds. According to the information given in Table 3, the ratio of heifers to total dairy cows was 28.6%, a ratio that is rather high compared to the need of cow replacement. This probably mean that more heifers were kept at this time because of the increase in the milk price.     

The data on reproduction performance, represented as the number of AI services for conception (Table 8) show a high fertility of heifers and low fertility in the milking cows. This result is agreement with Ho (1999) who found that AI use in smallholder dairy farms was 34% for milking cows.  In the case of heifers, nearly all (98%) became pregnant after 1 to 2 AI services. The high conception percentage of heifers shows that they are reared in good conditions. Otherwise conception was low in milking cows (> 3 AI services required for conception). Low fertility in dairy cows results from numerous factors, including genetics, environment and male fertility. It is estimated that about 80 percent of the variance in fertility is due to environmental factors, of which more than 50% is explained by nutrition (Lotthammer 1989). In feeding dairy cows maintaining a balanced diet is very important, as an excess as well as a nutritional deficiency can affect reproduction. By observation, the dairy cows in this area varied considerably in their body appearance and this may be related to the low conception ratio. In addition, the fertility rate also depends on the knowledge and skills of the farmer and the technical service, namely heat detection inaccuracies, poor semen quality, faulty insemination technique, reproductive tract infection etc. (Thiep and Trach 2004) 

Feed and feeding management

Green forages were from two main sources: cultivated and natural grasses. The farmers planted grass in the backyard, fallow land and used manure the cattle to fertilize the plots. The most popular cultivated grass was Napier grass (Pennisetum purpurerum), with an average fresh matter yield of from 230-250 ton/ha/year. The farmers could not supply sufficient fresh grass for their dairy cows during the dry season because of the lack of land and shortage of water at this time. The surplus of grass in the rainy season was not used to make either silage or hay, preserved as feed for the dry season.  None of the farmers planted any leguminous or fodder trees for their dairy.

Natural grasses (Digitaria adscendens, Panicum repens, Brachiaria mutica, Chloris barbata etc.) are the main roughage source for dairy cows in this area, especially in the dry season. Farmers find and collect grasses and weeds from the roadsides, fallow land and pasture.  Some of the farmers have to buy grasses from their neighbors, at a price of 400 VND per kg.

Rice straw was used as the main source of roughage in the dry season, when there is a lack of grass and/or a shortage of labor to collect enough green grass. Moreover, almost all farmers believed that rice straw could increase milk quality. Due to the urbanization pressure, the area of paddy land and supply of rice straw had decreased. Thus, the farmers have to buy rice straw off-farm with a price of 400 VND per kg. At present, the survey found that 88% of owners used rice straw to supply additional roughage. Rice straw was fed to the dairy cattle directly, without being chopped or subjected to any treatment.

According to the explanation of the farmers, brewery residues are very suitable for dairy cows. The nutritional values are higher than in other by-products, especially CP and digestible fiber. Its price was 800 VND per kg. One hundred percent of the farmers used brewery residues as feed for cows in fresh form, mixed with cassava waste and concentrate and water. In the present study, its nutrient values were lower than reported by Dong (2005), Manh et al (2003) and Nghi and Do (1995).

Cassava waste is the remaining part of cassava starch processing. In this region, it is the main source of by-product, and 100% of the farmers use it for their animals. In our study, the nutrient contents were higher when compared to the results reported by Nghi and Do (1995) and similar with Khang (2005).

The concentrates found in this area are commercial feeds, formulated from the abundance of available ingredients by the feed companies. The owners used concentrates as the main supplement source to their dairy cows, and fed from 3 to 6 kg/cow/day according to milk yield. Commercial concentrate, cassava waste and brewery residues were mixed with water and fed to the animals twice per day after milking. There were no households using homemade concentrates.

The feedstuffs and their proportions used in dairy cattle diets as discussed above represent typical feed and feeding regimes in the peri-urban areas of Hochiminh City. Similar conditions have been reported by Chantalakhana and Skunmun (2002) in Thailand. Of course farmers in this region use more concentrate and crop residues because of difficulties in land holding. Using local protein-rich foliages that are available in the region, such as cassava leaves, Tropical Kudzu, Gliricidia etc. (Ho Thanh Tham et al 2007; Hiep 2007; Man 2001) could reduce the need for concentrate and the feeding cost. However, in our study no farmers were found that used these foliages.    

In the present study, results for total dry matter intake both of milking cows and heifers were similar to the results reported in a survey of the usage of locally available feed resources in Hochiminh City by Khang (1999), and corresponded to the nutritional requirement if crossbred dairy cows suggested by Cai (1995). However, the dairy cattle were fed a higher ratio of concentrates, which resulted in high feed cost and increased the risk of lactic acidosis syndrome in lactating cows (Leng 1997).  

Milk yield and quality 

Milk productivity in the study area is based mainly on HF crossbred cows with a high proportion of Holstein blood. Milk yield and composition of the studied cows was likely to be linked to many factors such as heterosis, genotype, selection, feeds and feeding, and milking management, as mentioned by Chantalakhana and Skunmun (2002). The average milk yield of the crossbred Holstein cows of 15.93 (SD=2.02) kg per day, was high compared with the values reported by Do and Hoang (2001) in the North of Vietnam and Chantalakhana and Skunmun (2002) in Thailand. Faced with the low price of milk during the last two years, farmers in the region have started to select the high yielding cows to keep in their farms and sell the lower-yielding animals, which may explain the high yields.   

The large variation in milk composition between the study farms (Table 8) is possibly due to differences in parity, individual cow performance, feed and feeding or management (Schmidt and Van Vleck 1974; Sargeant et al 1998; Kennelly et al 1999; Hurley 2003). However, the obtained values were similar to those reported by Madalena et al (1990) and Teodoro and Madalena (2003) for crossbred HF in Brazil, and could be considered to be acceptable.    

Conclusions

• Dairy production is a new component in the small household production and is developing rapidly to meet consumer demand.

• Most of the dairy farmers interviewed practice intensive systems based on cut and carry of grasses, plus by-products and commercial concentrates.

• The main breed was mostly crossbred HF with a high HF blood proportion.

• Although the milk yield and milk quality were acceptable, problems of high feed cost and poor reproduction performance were the main constraints in dairy production development in Hochiminh City.  

Acknowledgments

The authors are grateful to the Swedish International Development Agency-Swedish Agency for research Cooperation with Developing countries (Sida-SAREC) for supporting this study. Thanks are also given to the farmers, and Departments of Agriculture and Rural Development in Hochiminh City, who supported and made it possible to conduct this study. 

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