Aflatoxin toxicity reduction in broiler diets

Introduction

Mycotoxins are substances produced by molds, that have a toxic effect on animals, decreasing their performance and even causing death. Molds are broadly distributed throughout the world, also contaminating feed grains.

In order to reduce the negative effects of mycotoxins on animals, mycotoxin-adsorbing feed additives are used. Such products have different neutralization abilities. The purpose of this study was to determine the in vivo mycotoxin adsorption capacity of T5X SD in broilers.

Materials and Methods

The study was performed in Instituto Samitec, RS, Brazil.

Three hundred (300) Cobb, male, one-day-old broiler chicks were housed cages, in an environmentally-controlled room. Cages were arranged in 4-story batteries. Each cage was divided in two sections with individual feeders and drinkers.

The following parameters were evaluated:

a) Weekly:

* Individual bird weight

* Feed intake

b) At 21 days:

* Feed conversion rate

* Liver:body weight ratio

* Total plasma proteins: 12 blood samples per treatment

A completely-at-random experimental design including 5 treatments and 6 10-bird repetitions was used. The statistical analysis was performed using the Statgraphics Centurion XV software (version 15.1). The means were compared using Bonferroni´s test (P≤0.05).

Feed and water (iso-nutrient ration) were given ad libitum throughout the experimental period (21 days).

Table 1. Inclusion levels of both aflatoxin and T5X SD adsorbent in the feed

*Treatment*	*No. of Birds*	*Aflatoxin (ppm)*	*T5X SD (%)*
01	60	-	-
02	60	-	0.50
03	60	2.8	-
04	60	2.8	0.25
05	60	2.8	0.50

The aflatoxins used in the study included: B1 - 93.80%; B2 - 2.10%; G1 - 3.40%; G2 - 0.70%.

Results and Discussion

Mean body weight at experiment start was 47.7 g, with no statistical differences among treatment groups (see Table 2).

From week 2 on negative effects of mycotoxin on feed intake (Table 2) and body weight (Table 3) were seen. By experimental day 21 feed intake in the only aflatoxin -fed group was lower than that in groups fed the aflatoxin + additive rations.

Table 2. Mean feed intake (g/bird) in the aflatoxin-fed broilers, with or without the addition of the T5X SD anti-mycotoxin additive, during 21 days

Time Period	P	Treatment groups
Controls	0.5% T5X SD	2.8 ppm Aflatoxin	Afla + 0.25% T5X SD	Afla + 0.5% T5X SD
Mean	CV¹	Mean	CV¹	Mean	CV¹	Mean	CV¹	Mean	CV¹
1 a 7 d	0.08	144.91 a	7	155.74 a	6	144.32 a	3	148.88 a	4	151.40 a	5
1 a 14 d	0.00	490.02 ab	5	521.01 a	3	418.27 c	9	445.13 bc	5	481.68 ab	7
1 a 21 d	0.00	1040.03 a	5	1035.28 a	3	840.46 c	3	928.90 b	5	1009.32 a	5

^{a - c Means in a line followed by different letters are statistically different by Bonferroni´s test (P≤0.05).
¹CV= Coefficient of variation (%).}

Table 3. Mean body weight (g) of aflatoxin-fed broilers with or without the addition of the T5X SD anti-mycotoxin additive, during 21 days

Time period	P	Treatment groups
Controls	0.5% T5X SD	2.8 ppm Aflatoxin	Afla + 0.25% T5X SD	Afla + 0.5% T5X SD
Mean	CV¹	Mean	CV¹	Mean	CV¹	Mean	CV¹	Mean	CV¹
Start	0.94	47.86 a	7	47.87 a	8	47.56 a	7	47.44 a	6	47.58 a	7
1 a 7 d	0.03	161.18 b	14	171.43 a	10	161.42 b	10	166.12 ab	12	165.42 ab	12
1 a 14 d	0.00	400.15 ab	18	418.40 a	13	320.58 d	17	354.68 c	16	381.69 bc	19
1 a 21 d	0.00	707.52 a	16	696.85 a	12	535.18 c	20	620.92 b	18	673.39 ab	19

^{a - d Means in a line followed by different letters are statistically different by Bonferroni´s test (P≤0.05).
¹CV= Coefficient of variation (%).}

The body weight of birds fed the aflatoxin plus the T5X SD additive was higher than that of birds fed only the aflatoxin (Figure 1).

Figure 1. Mean body weight (g) of broilers fed aflatoxins, with or without the T5X SD anti-mycotoxin additive, during 21 days

T5X SD feed additives efficiency on the aflatoxin toxicity reduction in broiler diets – In Vivo Study - Image 1

The addition of 2.8 ppm aflatoxin resulted in decreased body weight (-24.4%) and feed intake (-19.2%).

The inclusion of 0.5% T5X SD in the ration contaminated with 2.8 ppm aflatoxin resulted in increased body weight (+25.8%) and feed intake (+20.1%).

Feed conversion rate, liver:body weight ratio, and total plasma protein results are shown in Table 4.

Table 4. Feed conversion rate (FCR), mean liver:body weight ratio (g/100 g) and total plasma protein levels (TPP; g/dL) in broilers fed aflatoxin with or without the T5X SD anti-mycotoxin additive, during 21 days.

Time Period	P	Treatment groups
Controls	0.5% T5X SD	2.8 ppm Aflatoxin	Afla + 0.25% T5X SD	Afla + 0.5% T5X SD
Mean	CV¹	Mean	CV¹	Mean	CV¹	Mean	CV¹	Mean	CV¹
FCR	0.15	1.47 a	7	1.49 a	2	1.58 a	7	1.50 a	3	1.50 a	3
Liver	0.00	3.32 c	23	3.12 c	13	4.86 a	17	4.74 a	22	4.02 b	24
TPP	<0.01	3.15 a	12	2.72 ab	18	2.07 b	31	2.24 b	38	2.99 a	20

FCR showed no difference among treatments.

The liver:body weight ratio was higher in the birds fed the aflatoxin with or without the anti-mycotoxin additive, than in the controls. The inclusion of 0.5% of T5X SD resulted in reduced liver:body weight ratio as compared with the other treatments that caused mycotoxin toxicity. Total plasma protein levels were reduced as a result of the presence of aflatoxin in the feed, with the exception of birds in the group fed the aflatoxin plus 0.5% T5X SD, which showed total plasma protein levels similar to those in the controls.

The addition of 2.8 ppm aflatoxin resulted in increased liver:body weight ratio (+46.4%), and decreased total plasma protein levels (-34.3%).

The inclusion of 0.5% T5X SD in the feed contaminated with 2.8 ppm aflatoxin resulted in decreased liver:body weight ratio (-17.3%) and increased total plasma protein levels (+44.4%).

Conclusion

The inclusion of 0.5% of the T5X SD anti-mycotoxin additive to a feed containing 2.8 ppm aflatoxin was effective in decreasing the negative effects of aflatoxin on broiler performance.

Acknowledgements

Gratitude is expressed to Instituto Samitec (Santa Maria, RS, Brazil) for the execution of this study.

This paper was originally presented in Portuguese at the XXII Latin American Poultry Congress in Buenos Aires, Argentina in August, 2011. It´s been translated with the purpose of sharing the results with English speakers.