Preliminary research results on application of a local medicinal herb (Achyranthes aspera) as dietary
supplement to sows
to prevent diarrhea in piglets
Pham Hong Son, Pham Quang Trung, Tran Quang Vui and Dinh Thi Bich Lan
Hue University of Agriculture and Forestry
phson.nl@hueuni.edu.vn
Abstract
Diarrhea in piglets can be a good model for studying the effects of medicinal herbs on animals.
With the aim to test the possible positive and negative effects of the herb “co xuoc”, which is recommended to treat diarrhea in suckling children, levels of 0, 20 and 40 g (fresh material) were given per os to groups each of 3 sows from day 100 of gestation through lactation to weaning at 45 days post-parturition. Measurements were made of incidence of diarrhea, litter size and weight gain performance of the piglets, as well as on their immune response and gut microflora.
The analysis of the data indicated that “co xuoc” supplementation to sows decreased diarrhea prevalence in piglets, increased their growth rate but decreased the litter size. There was no apparent effect on the immune response of piglets and on their gut microbial flora.
Key words: “co xuoc”, medicinal herbs, sows, pregnancy, lactation, diarrhea, weaning weight, litter size, gut microflora, immune response
Introduction
Introduction
Diarrhea in piglets is an important disease
as it commonly appears in piglets from the 1st to 20th day of age, causing high
mortality, and subsequent economic loss (Dao Trong Dat et al 2001). Treatment of diseased neonatal animals
with antibiotics often leads to their growth retardation. Adding antibiotics to feeds as preventative agents
can lead to selection of drug-resistant bacterial strains. Application of probiotics and prebiotics
instead of antibiotics as feed supplements is a new choice; use of medicinal
herbs comes into this category. In
The aims of the experiment were to test if the herb "Co Xuoc":
-
might cause troubles to pregnant pigs
-
given to sows would prevent diarrhea in the piglets
-
would increase body weight of weaning pigs
-
would cause an immune response and changes in the gut microbial flora
Methods
Nine sows in their second gestation were used. Starting on the 100th day of gestation (about 15 days before farrowing), and during lactation, three of them were given per os 20 g daily (dose recommended for humans), another three were given 40 g (double-size dose) and the third group of three sows was used as negative control. The health condition of the animals was observed daily. After farrowing, live weight of the piglets was measured at birth, 15, 30 and 45 days later. Samples of faeces were collected on the 5th, 10th, 15th, 20th, 25th, 30th, 35th, 40th and 45 th days for determining total aerobic microbial flora as well as of Escherichia coli, and Salmonella plus Shigella. Observations were made of diarrhea prevalence in the piglets. On the 20th day of age each piglet was injected with a dose (as used for 5 chickens) of Newcastle disease virus (NDV) vaccine as a marker antigen for measuring humoral immune responses of the animals, which was determined 10 and 20 days later (at 30 and 40 days of piglet age).
The following parameters were recorded:
-
Body weight measured individually, with an exception of the weights at birth which were determined for the litter as a whole;
-
Diarrhea prevalence (if visible over a period of 5 days is counted as one case), cases/total number of piglets;
-
Total aerobic bacteria: numbers of 24-hour-incubated colonies on nutrient agar medium contaminated with 0.2 ml of serially diluted (to 107) faeces samples (Cottral 1978) ;
-
E. coli and Salmonella+Shigella: the numbers of genus-specific 24 h colonies on differential (EMB and Istrati) agars (Cottral 1978);
-
Immune response: antibody titers to NDV with haemagglutination inhibition reaction (HI) (Cottral 1978).
For
data analysis, mean values, standard deviation and ANOVA were used (Snedecor and Cochran 1980). Eliminatory analysis with range correlation (Spearman method of analysis;
reviewed in
Snedecor and Cochran [1980]) was
applied to non-experimental parameters, such as effects of litter size on piglet
diarrhea prevalence, and on weaning body weights (45 day age).
Results
Diarrhea prevalence in piglets
Per os application of the herb (Achyranthes aspera) to the sows decreased
diarrhea in the piglets (Table 1; Figure 1). However, attention should be paid on the number of piglets
in experimental and negative control groups, which wouldl be tested father by
analyzing the effect of non-experimental factors.
There was no relationship between the herb application and the counts of total aerobic microbes, E. coli and Salmonella+Shigella in piglet faeces. The numbers of the microbes (data not shown) were also not different in animals showing diarrhea or not showing diarrhea, indicating that the numbers of microbes may not be related to diarrhea in piglets. However, if the data of the bacterial numbers five days after birth are analyzed they appear to show a positive effect of "coxuoc" on microbial flora changes (Table 1).
|
Table 1. Mean numbers (with SD) of aerobic microbes, Escherichia coli, and Salmonella+Shigella (as 106/g) in faeces of piglets from the different experimental groups |
||||||||||
|
Trials |
Microbs |
Age days of piglets |
||||||||
|
5 |
10 |
15 |
20 |
25 |
30 |
35 |
40 |
45 |
||
|
0g |
Total aerobs |
4059 ±1167 |
2050 ±38.7 |
431 ±124 |
790 ±224 |
483 ±154 |
944 ±131 |
826 ±201 |
523 ±60 |
371 ±61 |
|
E. coli |
175.98
±58.21 |
84.92
±19.46 |
59.92
±19.46 |
250.75
±87.66 |
121.53
±43.36 |
408.63
±70.69 |
335.34
±130.46 |
82.81
±22.20 |
96.59
±24.35 |
|
|
Sal.+ Shi |
357.41
±133.29 |
19.98
±12.65 |
20.27
±12.65 |
75.34
±41.93 |
51.44
±27.96 |
82.35
±12.68 |
57.32
±20.33 |
32.33
±8.55 |
19.12
±7.30 |
|
|
20g |
Total Aerobs |
463.06
±121.16 |
1816.02
±327.86 |
3368.02
±408.95 |
747.49
±71.89 |
865.95
±127.28 |
425.76
±128.83 |
588.94
±88.44 |
518.00
±77.37 |
485.22
±148.5 |
|
E. coli |
111.68
±45.53 |
220.96
±42.39 |
276.14
±72.83 |
179.54
2±2.29 |
272.43
±79.89 |
73.78
±15.98 |
247.15
±58.15 |
202.92
±37.45 |
170.13
±56.43 |
|
|
Sal.+ Shi |
112.04
±42.21 |
58.59
±19.17 |
196.32
±45.86 |
48.32
±7.78 |
49.23
±11.65 |
31.25
±5.41 |
92.93
±30.43 |
28.44
±6.45 |
14.5
±5.56 |
|
|
40g |
Total Aerobs |
184.51
±33.82 |
215.12
±46.39 |
360.14
±100.62 |
102
±26.4 |
375.28
±41.78 |
652.16
±96.3 |
114.77
±41.27 |
114.43
±19.37 |
389.76
±69.13 |
|
E. coli |
22.37
±4.88 |
59.47
±17.63 |
139.92
±65.26 |
32.7
±2.0 |
90.82
±18.09 |
245.79
±54.65 |
52.99
±28.94 |
74.16
±30.26 |
203.42
±50.28 |
|
|
Sal.+ Shi. |
5.2
±1.05 |
14.99
±3.80 |
13.27
±4.06 |
4.1
±0.7 |
15.40
±3.67 |
74.91
±21.07 |
14.65
±9.00 |
8.59
±2.99 |
28.21
±6.76 |
|
Immune response of piglets
Figure 2: Immune response of piglets to NDV antigen
Growth rate of piglets
The growth rate of the piglets increased according to the level of the herb administered to the sows (Figure 3).
Figure 3: Changes in live weight of the piglets in response to administration of the herb to the sows
5. Eliminatory analysis
Eliminatory
analysis is to determine effects of non-experimental factors on experimental
animals. As a rule, if the absolute value of the correlations are higher than
0.8 (| r| > 0.8), that
experimental factors can not be further analyzed being considered to show too minute effect.
Correlation
between litter size and piglet diarrhea prevalence is -0.458, small enough to
support the experimental factors' analyses.
Correlation
between litter size and weaning body weight (at 45 day age) is shown in table
2. They are also small enough to support the experimental factors' analyses.
Table 2. Correlation between litter sizes and weaning body weight (at 45 day age)
|
Moments (post-partum) |
Correlation
values (r) |
|
10day |
0.34 |
|
15day |
0.40 |
|
20day |
0.38 |
|
25day |
0.54 |
|
30day |
0.48 |
|
35day |
0.48 |
|
40day |
0.32 |
|
45day |
0.63 |
Effect of "Co xuoc" on litter size
The effect of the herb on litter size is an important parameter as this medicinal species is not recommended to be used by pregnant women. The data in figure 4 appear to corroborate this recommendation as there is a suggestion that the litter size is reduced when increasing amounts of the herb were given to the sows in the later stages of pregnancy. At this stage (>100 days) of gestation, the foetuses have developed large enough to be aborted instead of being absorbed by the placenta. Further experiments are required to investigate the effects of the herb given during lactation.
Conclusions
Application of herbal medicines to prevent diseases in neonatal animals is a new but promising development. The results of our research are preliminary and require further testing. The tentative conclusions are:
-
Supplementation of “co xuoc” per os daily to sows in late pregnancy and during lactation:
-
Decreases diarrhea prevalence in the piglets and increases the growth rate to weaning
-
Appears to decrease litter size, although visible reproduction abnormalities (such as abortion and still-births) were not seen
-
Is not related to the gut bacterial flora and not related to humoral immune response.
Acknowledgements
This research was partially financed by the bilateral SAREC project
2000-2002.
References
Cottral C A 1978 Manual of standardized methods for veterinary microbiology. Cornell University Press, London, pp. 69-74.
Dao Trong Dat, Phan Thanh Phuong, Le Ngoc My and Huynh Van Khang 2001 Benh o lon nai va lon con [Diseases in sows and piglets, in Vietnamese], Nong nghiep Publishing House, Vietnam
Le Quy Nguu and Tran Thi Nhu Duc 1999 Duoc tai Dong y [Eastern medicinal materials, in Vietnamese]. Thuan Hoa Publishing House, Vietnam
Snedecor G W and Cochran
W G (eds.) 1980 Statistical methods, 7th ed., the
Iowa State University Press Ames, Iowa,
USA.