Livestock Research for Rural Development 21 (7) 2009 Guide for preparation of papers LRRD News

Citation of this paper

Ensiling with or without additives to preserve pineapple residue and reduce pollution of the environment

Nguyen Thi Hong Nhan, Nguyen Van Hon and T R Preston*

College of Agriculture, Cantho University, Cantho, Vietnam
nthnhan@ctu.edu.vn
* TOSOLY, AA48 Socorro, Santander, Colombia

Abstract

A preliminary study was done to evaluate effects on fermentation characteristics and nutritive value of ensiling pineapple residue with different additives.  Fresh pineapple residues (about 5 kg) were ensiled in plastic bags without or with 20% of poultry litter or rice polishings, or ground maize cobs. Samples of freshly processed pineapple waste were taken on the day of ensiling and of the ensiled product after 7, 14, 21, 30 and  60 days to determine their nutritive value.

After 60 days of ensiling, the quality of all silages was acceptable in terms of odour and appearance, with  pH in the range of  2.92 – 3.75, the higher value being with poultry litter as additive. Lactic acid concentration reached 2.28- 3.08 % in dry matter (DM) after 60 days.  Ammonia-N as percentage of total N increased in all silages with ensiling time, the effect being most pronounced in the waste ensiled with poultry litter.

In an on-farm feeding trial with 12 young cattle fed a locally available grass (Sacciolepis interrupt), growth rate was increased by supplementing the grass with fresh pineapple residues. There were no apparent benefits from the pineapple residues ensiled with rice polishing as the supplement.

Key words: Cattle, growth, maize cobs, poultry litter, rice polishings, Sacciolepis interrupt


Introduction

Pineapple production in Vietnam is estimated to be about 425,000 tonnes per year (FAO 2006). Recently, pineapple processing for fruit manufacture has developed rapidly. From this large quantity of pineapple, there are available considerable quantities of by-products (50-80%) that can be used as a feed resource for raising animals (Preston and Leng 1987; Devendra 2001).

However, one constraint is that pineapple residues collected after processing contain a very high percentage of moisture, which could make it difficult to conserve as a feed resource for long term use.

A more sustainable method than dehydration for conserving these materials is to ensile them with additives such as poultry litter, maize cobs or rice polishings to absorb the excess moisture in the pulp. Poultry litter also supplies nitrogen and may act as buffer to slow the rate of fermentation.

This research focuses on the effects of ensiling pineapple pulp with different additives and its later use as feed for growing cattle.

 

Materials and methods

Experiment 1: Effect of different by-products on quality of ensiled pineapple residues

Four treatments were evaluated:

NA : Fresh pineapple residue ensiled with no additives

PL: Fresh pineapple residue ensiled with 20% poultry litter (dry basis)

RP: Fresh pineapple residue ensiled with 20% rice polishing (dry basis)

MC: Fresh pineapple residue ensiled with 20% ground maize cobs (dry basis)

The fresh pineapple residue with or without additive was put in two inserted polyethylene bags (four per treatrment) and compressed by foot to expel air. The polyethylene bags were tightened using rubber bands, and stored to allow fermentation to occur. The silages were analyzed for pH, DM, crude protein, NH3-N, and organic acids  at 0, 7, 14, 21, 30 and 60 days after ensiling. Analytical methods were those of AOAC (1990).

Experiment 2: Effect of ensiled pineapple residue on performance of growing cattle

The feeding trial was undertaken for 90 days at a farm in Cantho city. The experiment was arranged in a randomized complete block design with 3 treatments.

SI: Sacciolepis interrupt grass ad libitum

            SIFPR: Restricted grass (0.75% of LW DM basis) plus fresh pineapple residue

SIEPR: Restricted grass (0.75% of LW DM basis) plus fresh pineapple residue ensiled with 20% rice polishing (dry basis)

Twelve growing cattle (Local Yellow x Sindhi) with initial weight in the range 119-124 kg were divided into 3 groups, considering the live weight and randomly allocated to the treatments:        

The animals were vaccinated against foot and mouth disease and dewormed before the initiation of the experiment. They were confined in a shed with free access to drinking water and a mineral lick. In treatment SIEPR the pineapple residues were ensiled with rice polishings following the method used in Experiment 1 (Photos 1 and 2).

Feeds were offered once daily at 09.00h after discarding the previous day's residue. The cattle were weighed at the beginning and again at monthly intervals. Chemical composition of feeds and refusal were determined by standard methods (AOAC 1990). Ensiled pineapple residue is shown in Photo 1.

Statistical analysis

All data were coded for subsequent statistical analysis using the general linear model option of the ANOVA software of Minitab (release13.2). In Experiment 1, sources of variation  were: Additives, time, Additives*time and error. In experiment 2, sources of variation were: treatments and error.


Photo 1: Farmers ensiling pineapple residue
for feeding cattle

Photo 2: The ensiled pineapple waste stored
in polyethylene bags

Results and discussion

Experiment 1: Effect of different additives on ensiling pineapple residue quality

As was to be expected, the DM content of the silages was increased by all the additives with the highest values for the silages with rice polishings (Table 1).


Table 1. Effect of ensiling period on the DM content in ensiled pineapple residues (%)

 

Days

SEM

P

0

7

14

21

30

60

No additive

21.5

19.9

19.6

19.0

18.1

17.9

0.4

0.001

Maize cobs

22.9

20.0

19.4

18.9

18.2

18.2

0.3

0.001

Rice polishings

23.3

19.5

19.4

19.2

19.3

19.6

0.6

0.001

Poultry litter

23.4

22.1

20.6

19.6

19.6

18.9

0.3

0.001

SE

0.5

0.2

0.4

0.5

0.6

0.2

 

 

P

0.001

0.001

0.02

0.8

0.1

0.001

 

 

All treatments produced acceptable silage in terms of smell and appearance. The pH in the fresh pineapple residue was already low (3.97) before ensiling (Table 2). There was a rapid decrease of pH in the first week, which continued up to 21 – 30 days after which it stabilized at values below 3.0, except for the silage with poultry litter which remained at 3.75.

 

In our study the lactic acid content in the silages of all treatments increased rapidly in the first week and continued increasing until 14 days of ensiling (Table 2; Figure 1). Acetic acid concentrations also increased but to a lesser extent than for lactic acid.


Table 2. Effect of ensiling period and additives on pH and content of lactic and acetic acids content in pineapple residues ensiled with maize cobs, rice polishings or poultry litter

 

 

Days

SEM

P

0

7

14

21

30

60
pH

No additive

3.97

3.90

3.00

2.97

2.96

2.92

0.3

0.001

Maize cobs

3.44

3.18

3.12

3.14

2.94

2.92

0.02

0.001

Rice polishings

3.71

3.24

3.17

2.86

2.76

2.91

0.08

0.001

Poultry litter

4.14

3.8

3.76

3.76

3.74

3.75

0.02

0.01

SE

0.03

0.03

0.02

0.03

0.04

0.02

 

 

P

0.001

0.001

0.001

0.001

0.002

0.001

 

 
Lactic acid,
 g/kg DM

 

No additive

0.61

1.75

2.25

2.52

2.53

2.88

0.06

0.001

Maize cobs

0.62

2.01

2.37

2.82

2.85

2.93

0.07

0.001

Rice polishings

0.55

1.95

2.07

2.10

2.65

3.08

0.05

0.001

Poultry litter

0.44

1.83

2.13

2.19

2.26

2.28

0.06

0.001

SE

0.02

0.03

0.06

0.06

0.07

0.08

 

 

P

0.001

0.001

0.015

0.001

0.001

0.150

 

 

Acetic acid,
 g/kg DM

 

No additive

0.41

1.17

1.50

1.68

1.69

1.92

0.039

0.001

Maize cobs

0.41

1.34

1.58

1.21

1.63

1.95

0.05

0.001

Rice polishings

0.36

1.30

1.38

1.40

1.77

2.05

0.04

0.001

Poultry litter

0.29

1.22

1.42

1.53

1.18

1.85

0.04

0.001

SE

0.01

0.02

0.04

0.04

0.05

0.06

 

 

P

0.001

0.001

0.015

0.001

0.001

0.001

 

 


Figure 1. Trends in lactic acid content of the silages with duration of ensiling

The total crude protein content in the silages tended to increase with ensiling time (Table 3; Figure 2), probably because of some loss of volatile substances during the ensiling process. Pineapple residues ensiled with poultry litters had higher crude protein than other treatments reflecting the higher N content in this additive. The ammonia-N content of the total N increased in all the silages with ensiling time, the effect being more pronounced with silages made with poultry litter..

The increase in ammonia-N is indicative of some breakdown of the protein, which would be facilitated by the relatively higher pH in the pineapple waste ensiled with poultry litter.


Table 3: Effect of ensiling period and additives on the crude protein and NH3-N in pineapple residues ensiled with maize cobs, rice polishings or poultry litter

 

 

Days

SEM

P

0

7

14

21

30

60

NH3-N, % of total N

 

No additive

1.6

2.3

3

2.8

3.1

3.6

0.01

0.001

Maize cob

2.3

2.6

3

3.4

3.7

2.3

0.02

0.001

Rice polishing

2.7

3.3

3.5

4.1

4.5

4.7

0.04

0.09

Poultry litter

5.6

9.1

10.4

13

11.7

12.6

0.04

0.001

SE

0.03

0.02

0.01

0.2

0.03

0.02

 

 

P

0.001

0.001

0.001

0.001

0.001

0.001

 

 

Crude protein, % in DM

 

No additive

3.6

4.7

4.0

4.2

4.8

4.8

0.2

0.001

Maize cob

4.8

4.5

5.0

4.3

4.5

5.4

0.6

0.070

Rice polishing

6.9

6.6

5.7

5.7

6.0

6.6

0.5

0.681

Poultry litter

9.6

11.2

13.7

13.5

14.4

13.9

0.5

0.001

SE

0.2

0.3

0.5

0.4

0.7

0.1

 

 

P

0.001

0.001

0.001

0.001

0.001

0.001

 

 
                     


Figure 2. Trends in crude protein content
of the silages with duration of ensiling


Figure 3. Trends in NH3-N as % of total N
in the silages with duration of ensiling

Experiment 2: Effects of supplementation of fresh pineapple residue treated on performance of growing cattle
The highest daily live weight gain was recorded on the diet of grass supplemented with fresh pineapple waste (Table 4). Feed intake and conversion did not differ among the treatments.

Table 4. Mean values for feed intake and feed conversion of cattle fed Sacciolepis interrupt grass (SI) and fresh pineapple waste (SIFPR) or pineapple waste ensiled with rice polishing (SIEPR)

 

Treatment

SEM

Prob

SI

SIFPR

SIEPR

Live weight, kg

Initial

120

119

124

2.8

0.4

Final weight

144

148

150

3.7

0.5

Daily gain, g

271b

324a

295b

10.8

0.04

DM intake, % LW

2.29

2.44

2.35

0.1

0.9

DM feed conversion

10.7

9.83

11.1

0.4

0.3

ab Means in the same row without common superscript are different at P<0.05


It appears that ensiling the pineapple waste with rice polishings conferred no nutritional benefits compared with feeding the fresh waste, when the basal diet was fresh grass. On such a basal diet the limiting nutrients are likely to be fermentable carbohydrates which would be slightly higher in the fresh pineapple waste as some of the sugars were already fermented in the ensiling process.

The advantage of ensiling the pineapple waste will be the management of this product which would be facilitated by ensiling, whereas use of the fresh product implies daily visits to the processing factory.


Conclusions


Acknowledgments

The support from the MEKARN project, financed by Sida, is gratefully acknowledged. Thanks are also due to the farmers who shared their experiences and participated actively in this study. 


References

AOAC 1990 Official methods of analysis (15th Edition). Association of Official Analytical Chemists, Arlington, VA.

Devendra C 1992 Non-conventional feed resources in Asia and the pacific. Strategies for Expanding Utilisation at the Small Farm level. FAO-APHCA. 73-105.p.

FAOSTAT 2006 FAO statistical Database. Food and Agriculture Organization of the United Nations. Rome. http://faostat.fao.org/default.jsp.

MINITAB 2000. Minitab Reference Manual, PC Version, Release 13.2. Minitab Inc., State College, PA.

Preston T R and Leng R A 1987 Matching Ruminant Production Systems with Available Resources in the Tropics and Subtropics. PENAMBUL Books Ltd: Armidale NSW, Australia .



Received 3 April 2009; Accepted 14 June 2009; Published 1 July 2009

Go to top