Livestock Research for Rural Development 25 (8) 2013 Guide for preparation of papers LRRD Newsletter

Citation of this paper

Feeding systems for fattening cattle on smallholder farms in Central Vietnam

D V Dung, W Yao, N X Ba* and H Kalhoro

College of Animal Science and Technology, Nanjing Agricultural University, China
yaowen67jp@njau.edu.cn
* Faculty of Animal Sciences and Veterinary Medicine, Hue University of Agriculture and Forestry, Vietnam

Abstract

A study was carried out to investigate feeding system for fattening cattle at smallholder in Central Vietnam including: farming resources, feed resources, feed intake, diet structure and average daily gain (ADG) of cattle. A total of 40 households were randomly selected to collect data by recording daily from beginning to end of fattening cattle process.

 

Results showed that 100% of households used at least two kind of concentrate and more than 65% of households used elephant grass or native grass for cattle. Dry matter (DM) intake ranged from 5.54 to 5.89 kg/day. Concentrate and crude protein (CP) proportion in diet was from 24.0 to 37.0% and 8.37 to 9.82%, respectively. The ADG of cattle was from 0.43 to 0.69 kg/day. In conclusion, feed resources for fattening cattle at smallholder were variety, of which included concentrate and roughage feed, however, concentrate and CP proportion in diet was low.

Keywords: feed intake, diet structure, household, Vietnam


Introduction

Cattle production plays a very important role in Vietnam and most of cattle are kept by smallholder farmers. Maltsoglou and Rapsomanikis (2005) found up to 23.9% of households in Vietnam kept cattle. About 40% of the total number of cattle in the country is kept in the Central region (GSO 2012). In recent years, demand for beef is increasing, particularly in the major urban centers - due to both tourism and increasing disposable income of the local population (GSO 2012).  Growth in cattle demand is led primarily through domestic demand, and an estimated 95% of beef is consumed domestically, particularly in Ho Chi Minh City which is the market for an estimated 70-80% of cattle from the Central region. However, every year large quantity of beef was imported from outside to fill the demand shortfall in Vietnam. According to statistical data collected from the Vietnam national livestock corporation (VILICO 2012), cattle and buffalo meat imported to Vietnam in 2011 was 9,000 tonnes or around USD 35.25 million, increased 40.87% compared to 2010. Furthermore, large numbers of live cattle and buffalo were also imported legally and illegally to Vietnam from China, Thailand, Laos, and Myanmar. The Department of Animal Health (2010) reported about 5,700 head of breeding cattle and buffalo and 47,000 head of fattening animals from Thailand and Lao were registered for veterinary check at the end of 2009. On the other hand, large numbers of live cattle and buffalo were imported illegally through the borders between Vietnam and Laos, Cambodia or China that might not be recorded and controlled (Hoang 2011).

All above indicates that the demand of beef production in Vietnam is rapidly increasing, so it creates  an opportunity for smallholder farmers in Central Vietnam where fattening cattle activity is quickly developing in recent years. However, there are a number of obstacles that need to be addressed in order for the opportunity to be realized, especially feeding quality and quantity.

 

Appropriate measures should be taken to understand the current situation of feeding of fattening cattle system in Central Vietnam. Therefore, the objective of this study was to capture different aspects of feeding for fattening cattle in Central Vietnam including: farming resources, feed resources, diet structure, feed intake and live weight gain of cattle under condition of fattening at smallholder.


Materials and methods

Description of study area

 

Four provinces (Phu Yen, Binh Dinh, Quang Ngai and Thua Thien Hue) of Central Vietnam were selected for present study where the cattle fattening farms are developing (Figure 1). One district was selected from each province namely Tuy An, Phu Cat, Duc Pho and Quang Dien from Phu Yen, Binh Dinh, Quang Ngai and Thua Thien Hue, respectively. In order to be representative of intensive cattle production, one commune was selected from each i.e. An Chan, Cat Trinh, Pho An and Quang Tho in Tuy An, Phu Cat, Duc Pho and Quang Dien, respectively. Data was randomly collected from 10 households in each commune which have fattening cattle activity (in captivity, fed at stall).


Figure 1. Location of the four study provinces in the map of Vietnam
Data collection

 

Data were collected daily from the beginning to the end of fattening cattle process. Feedstuffs were kind of feed which farmer used for cattle in fattening period and were recorded daily at each household. Feed intake was measured daily by recording the quantity of feed offered and refused. Live body weight was recorded as initial body weight at the start and final body weight at the end of the fattening cattle process whereas the ADG (kg/day) was calculated as: (final body weight, kg – initial body weight, kg)/fattening days.

 

Diet-types, Chemical composition and Analytical procedure

 

Feedstuffs offered daily for cattle were categorized into concentrates and roughages (Table 1) and their chemical composition was analysed (Table 1). DM and nitrogen (N) contents were analyzed according to AOAC (1990). CP content was calculated as N6.25. Metabolizable energy (ME) content was determined on the basis of composition and nutritive value of animal feed according to National Institute of Animal Husbandry, Vietnam (NIAH 2001). The DM, CP and ME contents of industrial feed were based on manufacturer’s data (Product of Green feed company).

Table 1. The chemical composition of feedstuffs fed to cattle during cattle fattening process

Feedstuffs

Composition

DM (%)

CP (%)

ME (MJ/kgDM)

Concentrates

Rice bran

89.1

11.8

10.6

Maize

86.9

10.5

11.4

Cassava root meal

87.7

2.4

11.2

Protein supplement*

88.0

46.0

10.5

Rice

87.7

8.34

11.3

Groundnut cake

91.1

49.2

12.5

Roughages

Rice straw

87.2

5.6

8.1

Elephant grass

16.0

12.1

8.5

Native grass

21.8

11.6

8.6

DM: dry matter, CP: crude protein, ME: metabolizable energy
*
DM, CP and ME of protein supplement based on data recorded on the packaging of the product (Product of Green feed company)

Total DM offered to the animals was total concentrate and roughage offered; while total DM intake was total concentrate intake plus roughage intake. Concentrate and roughage proportion in the diet was determined by the ratio of amount of concentrate or roughage offered to the total DM offered and crude protein proportion in concentrate was measured by the ratio of amount of CP offered from concentrate to the total amount of concentrate offered. Similarly, crude protein proportion in diet was determined by the ratio of amount of CP offered to the total DM offered while concentrate offered as % of body weight was measured by the ratio of average of concentrate offered to average of BW of cattle.

 

Data analysis

 

Data were presented as Means and standard error of the means (SEM). Significant differences at P<0.05 were determined by analysis of variance using statistical software SPSS version 17.0 (SPSS 2008).


Results and discussion

Farming resources

 

Resources for livestock production of household in four provinces are presented in Table 2. Farming resources including total population, total labour, total area and area of agricultural land were similar among four provinces. The average number of people engaged is 4.53 per household in the four provinces of Central Vietnam (varies from 4.00 in Phu Yen to 4.90 in Thua Thien Hue). The average labour units per household vary from 2.30 in Binh Dinh to 2.80 in Quang Ngai province, with more than half of the labour male. Of the average total land area 3919 m2 available per household, the proportion agricultural land is very high it ranges from 76 to 92% in the four provinces of Central Vietnam.

Table 2. Population, labour and cultivated land of households at Central provinces

Indicators

Provinces

SEM

Prob.

Phu Yen

Binh Dinh

Quang Ngai

Thua Thien Hue

Total population, people

4.00

4.60

4.60

4.90

0.45

0.549

Total labour, people

2.40

2.30

2.80

2.40

0.27

0.557

Male labour, people

1.10

1.20

1.60

1.30

0.19

0.292

Female labour, people

1.30

1.10

1.20

1.10

0.14

0.726

Total area, m2

3725

4100

4050

3800

286

0.744

Area of agricultural land, m2

2825

3550

3500

3515

228

0.089

Resources for cattle production play an important role in making decisions for production as well as foundation for acceptance of new techniques in cattle production, such as raising genetically high potential cattle and developing cultivated grass or concentrate supplement (Nelson and Cramb 1998; Savadogo et al 1998). Livestock production resources in present study were similar to those reported by Parsons et al (2013) who surveyed cattle production in South Central Coastal Vietnam.

 

Feedstuffs fed to cattle for fattening at smallholder in Central Vietnam

 

A variety of feedstuffs was fed to cattle during cattle fattening process at smallholders in Central Vietnam. Only three kinds of roughages (rice straw, elephant grass and native grass) were used for fattening cattle at small householder in Central Vietnam except in Thua Thien Hue province where only two kinds of roughages (rice straw and native grass) were used (Table 3).

Table 3. Feedstuffs were used for fattening cattle at smallholder in Central Vietnam

Indicators

Phu Yen

(N=10)

Binh Dinh

(N=10)

Quang Ngai

(N=10)

Thua Thien Hue

(N=10)

Total

(N=40)

n

%

n

%

n

%

n

%

n

%

Concentrates

Rice bran

10

100

10

100

10

100

10

100

40

100

Maize

0

0

4

40

5

50

0

0

9

22.5

Cassava powder

9

90

1

10

9

90

10

100

29

72.5

Rice

10

100

10

100

10

100

10

100

40

100

Groundnut cake

0

0

0

0

2

20

0

0

2

5.0

Industrial feed

10

100

10

100

10

100

10

100

40

100

Salt

10

100

10

100

10

100

10

100

40

100

Roughages

Rice straw

10

100

10

100

10

100

10

100

40

100

Elephant grass

10

100

6

60

10

100

0

0

26

65.0

Native grass

10

100

8

80

6

60

10

100

34

85.0

N: Total household survey per province ; n: Number of household used feed

The table 3 indicated that 100% households used rice, rice bran and industrial feed for fattening cattle, however, only 72.5 and 22.5% households used cassava powder and maize, respectively. Especially, only 5% households supplemented groundnut cake for fattening cattle. Central is region which has highest cattle population of Vietnam with more 40% (GSO 2012). Most cattle are integrated in smallholder mixed crop – livestock systems, therefore cattle are abundantly supplied feed. Ngoan and Giang (2008) reported that next to the elephant grass, native grass and rice straw, some by-products from crops such as corn leaf, leaf cane, vines of sweet potatoes, peanuts and other beans are also used as feedstuffs for cattle in Central Vietnam and are used only at the time of harvest and depends on the ecoregion. A survey in Quang Ngai province showed that 97.8% of households used agricultural by-products as feed for ruminants including rice straw, maize stems and leaves, peanut vines, and sugar cane leaf (Ba et al 2008b). However, in the present study all of the households used rice straw, elephant grass or native grass only as roughage feed for cattle, maybe this is also a waste because the agricultural by- products in Vietnam in general and in Central region in particular are very diverse and abundant.

 

Traditionally rice straw has been important roughage for the ruminants in the tropics (Chanthakhoun et al 2012, Wanapat 2009). The present study showed that the households in Central Vietnam predominantly used rice straw for cattle. However, rice straw contains low level of crude protein, energy and minerals, it is essential to improve the nutritional value by either using physical or chemical treatments with or without concentrate supplementation (Wanapat 1999, 2009). In the present study we found that about 70% of households in central Vietnam fed roughages to their cattle supplemented with concentrates such as cassava powder, rice bran, rice and industrial feed. However, only 22.5% of households used maize as concentrate supplementation with roughages for cattle.  Ngoan and Giang (2008) reported that over 80% of household used cassava powder, rice bran, maize and industrial feed for cattle, whereas in another survey by Ba et al (2005) and RUDEP (2005) in Quang Ngai province showed lower use of these concentrates with 50%.

 

Feed intake of fattening cattle at smallholder in Central Vietnam

 

The average feed intake (kg/day) is 4.06 for roughages and 1.65 for concentrates at smallholders in the four provinces of Central Vietnam. Roughage and concentrate intakes were higher (P<0.001) in Quang Ngai as compared with other three provinces (Table 4). However, total average DM intake is 5.54 (Phu Yen province) to 5.89 kg/day (Binh Dinh province), respectively for 2.71 or 2.86% of body weight and was not significantly different (P>0.05) among the four provinces. The ME intake was similar however, the CP intake showed great variation among the provinces, being higher (P<0.01) in Quang Ngai compared to other three provinces.

Table 4. Feed intake of fattening cattle at smallholder in Central Vietnam

Indicators

Provinces

SEM

Prob.

Phu Yen

Binh Dinh

Quang Ngai

Thua Thien Hue

Concentrate, kg DM/day

1.64a

1.45a

2.12b

1.38a

0.10

<0.001

Roughage, kg DM/day

3.90ac

4.44b

3.62a

4.38bc

0.13

<0.001

Total DM intake, kg/day

5.54

5.89

5.74

5.76

0.13

0.288

Total DM intake, % of BW

2.71

2.83

2.76

2.86

0.07

0.353

ME intake, MJ/day

49.7

51.7

52.8

50.5

1.17

0.280

CP intake, kg/day

0.49a

0.50a

0.56b

0.49a

0.02

0.006

a b Values on the same row with different superscripts differ (P<0.05)

In Vietnam, feeding standard for beef cattle is based on suggestion by Kearl (1982) who reported that in developing countries, cattle with body weight of 150-200 kg and daily weight gain of about 0.5-1.0 kg/d, their DM intake were 2.8-3.0% of body weight. The total DM intake of cattle at smallholders in Binh Dinh, Quang Ngai and Thua Thien Hue provinces were similar as per suggestions by Kearl (1982), whereas, it was lower in Phu Yen province. The ME intake of cattle in the present study was higher than suggestion of Kearl (1982), whereas the CP intake of cattle was lower. Many studies have indicated that cattle fed low digestibility forages supplemented with appropriate amount of concentrates increased daily weight gain (Ba et al 2008a, Hennessy et al 1995, Lee et al 1987, Wanapat and Khampa 2007). Better use of concentrate for example, increasing its intake up to 2% of body weight through frequent feeding will increase growth rate of cattle and would aid in the income and profit of smallholders in Vietnam (Ba et al 2008a). However, the present study survey revealed that concentrate intake of cattle in the four provinces of Central Vietnam was very low as suggested by Ba et al (2008a). 

 

The structure of diet (concentrate to roughage ratio) for fattening cattle at smallholder in Central Vietnam

 

Structure of the diet was measured on the basis of feed offered to the cattle. The ratio of concentrate to roughage in the diet fed to cattle at smallholder varied greatly among the provinces, being higher (P<0.001) in Quang Ngai compared to other three provinces (Table 5). Accordingly, the concentrate intake was higher (P<0.001) in Quang Ngai as compared to other three provinces where the average concentrate intake was approximately 0.75% of body weight. The CP content in the concentrate as well as in the diet fed to cattle at smallholder varied greatly among the provinces, being highest (P<0.01) in the Quang Ngai as compared to other three provinces in the central Vietnam. The ME content in the diet fed to cattle at smallholder in the four provinces of central Vietnam raged from 8.76 to 9.20 MJ/kgDM (P<0.05).

 

Protein or nitrogen is the key component in ruminants ration and an appropriate CP level is of utmost importance (Islam et al 2002, Bailey et al 2008). The CP levels in concentrate were determined in large part by the quality of forage consumed and concentrate resources. Level of CP in diet in our results are in agreement with Ngoan and Giang (2008) who documented that CP proportion in diet for cattle at finishing period was 9.9% in Quang Ngai province. Dietary energy density in present study ranged from 8.76 to 9.2 MJ/kg DM, this observation was similar to Kearl (1982) who suggested that energy density in diet for cattle having body weight 150-200 kg and daily weight gain 0.5-1.0 kg/day in developing countries was from 7.95 to 10.01 MJ/kg DM.

Table 5. The structure of diet for fattening cattle at smallholder in Central Vietnam

Indicators

Provinces

SEM

Prob.

Phu Yen

Binh Dinh

Quang Ngai

Thua Thien Hue

Concentrate in diet, %

29.5a

24.7a

37.0b

24.0a

1.65

<0.001

Roughage in diet, %

70.5a

75.3a

63.0b

76.0a

1.65

<0.001

Concentrate to Forage ratio

1:2

1:3

2:3

1:3

 

 

Concentrate intake, % BW*

0.80a

0.70a

1.02b

0.69a

0.05

<0.001

CP in concentrate, %

10.7ab

12.3a

12.6a

9.56b

0.52

<0.001

CP in diet, %

8.84a

8.37a

9.82b

8.47a

0.17

<0.001

ME, MJ/kgDM

8.97a

8.78b

9.20c

8.76b

0.05

<0.001

abc Values on the same row with different superscripts differ (P<0.05)

*BW: Body weight

Weight gain and feed conversion

 

In accordance with the variations in concentrate and CP intakes, the growth performance parameters of fattening cattle at smallholder in central Vietnam showed great variations among the provinces (Table 6).

Table 6. Average daily gain of cattle at smallholder in Central Vietnam

Indicators

Provinces

SEM

Prob.

Phu Yen

Binh Dinh

Quang Ngai

Thua Thien Hue

Initial BW, kg

187

192

188

188

1.77

0.204

Final BW, kg

223ab

224a

228a

215b

2.16

0.001

Feeding time, day

66.1a

60.8ab

58.8b

62.4ab

1.64

0.022

ADG, kg/day

0.54a

0.53a

0.69b

0.43c

0.02

<0.001

FCR*, kg DM/kg ADG

10.4a

11.4a

8.48b

14.0c

0.48

<0.001

abc Values on the same row with different superscripts differ atP<0.05
*
Feed conversion ratio

The final body weight and ADG were highest in Quang Ngai province and lowest in Thua Thien Hue (P<0.001). Contrast, feed conversion ratio was highest in Thua Thien Hue province and lowest in Quang Ngai (P<0.001).The ADG in the present study was lower than observed in the previous studies (Ba et al 2008a, Cuong et al 2008, Dung et al 2011). This might be due to limited supply of concentrate level and low CP content in the diet fed to fattening cattle (Ba et al 2008a). Moreover, the present study showed that the performance of cattle was higher in cattle of those provinces where the level of concentrate and CP supply was higher and can further be increased with appropriate diet management in at smallholder in Central Vietnam.

 

The ADG of cattle in this trial had a positive linear relationship with the CP level in diet in Binh Dinh, Phu Yen and Thua Thien Hue province (Figures 4, 6, and 8), whereas FCR had a negative relationship (Figures 5, 7 and 9). These results are similar to Paengkoum and Tatsapong (2009). Increasing CP in diet contributed to increase ADG, which would be the causative factor of a reduction FCR of cattle. However, in Quang Ngai province and from data for four provinces indicated that ADG and FCR of cattle had a quadratic relationship with the CP levels (Figure 2, 3, 10 and 11). These results could be concluded that 11-12% CP in diet is valuable recommendation. However, in our study only two farmers (5% of total farmer surveyed in four provinces) in Quang Ngai province used CP in diet with 11-12% for cattle. The average of CP proportion in diet for four provinces is 8.88%, which is very low compare with CP level was recommendation.

Figure 2. Relationship between dietary crude protein level
and live weight gain for Quang Ngai province
Figure 3. Relationship between dietary crude protein level
and feed conversion rate for Quang Ngai province




Figure 4. Relationship between dietary crude protein level
and live weight gain for Phu Yen province
Figure 5. Relationship between dietary crude protein level
and feed conversion rate for Phu Yen province




Figure 6. Relationship between dietary crude protein level
and live weight gain for Binh Dinh province
Figure 7. Relationship between dietary crude protein level
and feed conversion for Binh Dinh province




Figure 8. Relationship between dietary crude protein level
and live weight gain for Thua Thien Hue province
Figure 9. Relationship between dietary crude protein level
and feed conversion for Thua Thien Hue province




Figure 10. Relationship between dietary crude protein level
and live weight gain (data for four provinces)
Figure 11. Relationship between dietary crude protein level
and feed conversion rate (data for four provinces)


Conclusions


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Received 23 April 2013; Accepted 28 June 2013; Published 1 August 2013

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