doi:10.5455/vetworld.2013.313-317 Effects of high grade bentonite on performance, organ weights and serum biochemistry during aflatoxicosis in broilers

Aim: To evaluate the effect of different levels of High Bentonite on growth performance, organ weight and serum biochemistry in broiler fed on diets containing aflatoxin. Materials and Methods: A total of 360 day-old commercial broiler chicks were divided at random into 8 dietary treatment groups of 42 chicks each having 3 replicates. Dietary levels of aflatoxin (0.5 ppm) and High-grade bentonite (0.5, 0.75 and 1.00%) were tested in a completely randomized design manner, forming a total of 8 dietary treatments each with three replicates. Body weight and feed intake were recorded weekly. At 5 wk, six birds from each treatment were sacrificed and liver, kidney, gizzard, pancreas, spleen, bursa of Fabricius and thymus were extracted and weighed. The serum samples were analyzed for total proteins, uric acid, serum albumin, serum globulin and the activities of gamma glutamyl transferase (GGT), alanine amino transferase (ALT) and for antibody titers against Newcastle disease (ND) and infectious bursal disease (IBD) using ELISA technique. Results: A significant (P<0.05) decrease in body weight, feed consumption, relative weights of bursa, thymus, serum protein, anti body titers against NDV and IBDV, and increase in FCR, mortality, relative weight of liver, kidney, and the activity of Gamma Glutamyl Transferase (GGT) was observed. However, the relative weights of gizzard, pancreas, spleen, serum albumin, uric acid and the activity of Alanine Amino Transferase (ALT) were not influenced by inclusion of AF or HGB. Conclusion: The addition of HGB restored the harmful effects of AF on body weight, feed consumption, FCR, mortality, relative weight of liver, kidney, serum protein, IBDV and NDV. Supplementation of high grade bentonite at 1.0 per cent level was found to be beneficial in ameliorating the adverse effects of aflatoxin (AF) in broiler chickens.


Introduction
has been reported to increase the toxicity symptoms in poultry [3].Cereal grains and associated by-products Among Aflatoxins (AF), AFB1 is the most potent constitute important sources of energy for poultry.
hepatotoxin having carcinogenic and severe However, there is increasing evidence that global performance depressive effects on poultry [4].At supplies of cereal grains for animal feedstuffs are present, one of the more encouraging approaches to frequently contaminated with mycotoxins.It is make the feed harmless is the addition of non-nutritive estimated that as much as 25 percent of the world's and natural adsorbent materials to the contaminated cereals are contaminated with known mycotoxins [1].
feed in order to selectively bind the mycotoxin during Aflatoxins are secondary toxic metabolites, the digestive process.The major advantages of these produced by certain strains of fungi, e.g.Aspergillus adsorbents include low cost, safety, and the ease of flavus and Aspergillus parasiticus species, of which addition to animal feed.aflatoxin B1 (AFB1), is the most toxic among all other Layered amino silicates, such as sodium aflatoxins i.e.AFB1, AFB2, AFG1 and AFG2.In bentonite, have been found effective in counteracting poultry, aflatoxin ingestion leads to "Aflatoxicosis" mycotoxins [5][6][7][8][9].However, the ability of bentonite to syndrome that is characterized by retardation in bind mycotoxins depends on pH, molecular growth, decreased feed consumption and feed arrangements, and its geographic region of origin [10].conversion efficiency, immunosuppression and the Considering all these facts, the present study was increase of mortality [2].Co-contamination of cereal undertaken to investigate the ability of high grade grains with other mycotoxins produced by different bentonite on aflatoxicosis in broilers.fungal genera, including Fusarium and Aspergillus, local hatchery , divided at random into 24 replicates of recorded weekly.At 5 wk, six birds from each 14 chicks each having equal number of males and treatment (3 males and 3 females) were humanely females.Each three such groups were allotted to one of slaughtered as per religious (Halal) method of the 8 dietary treatments with due permission from the slaughter by severing the carotid arteries and jugular Animal Ethics committee of Veterinary College, veins and liver, kidney, gizzard, pancreas, spleen, bursa Bangalore.
of Fabricius and thymus were collected and weighed.The weights were adjusted to one kg live weight and Experimental design and test diets: Dietary levels of the treatment means were calculated.AF (0.5 ppm) and High-grade bentonite (0.5, 0.75 and Blood was collected in non-heparinized tubes 1.00%) were tested in a completely randomized design from six birds in each treatment (3 males and 3 manner, forming a total of 8 dietary treatments each females) by puncturing the brachial vein during 5th with three replicates.Basal diet was formulated and week of age.Serum was collected after 8 to 10 hours as compounded to meet the nutrient requirements of per the standard procedures [13] and was stored at commercial broilers during the starter (0-3 wks) and -200C for subsequent analysis.The individual serum finisher (4-5 wks) phases (Table -1).
samples were analyzed for total proteins, uric acid, AF were produced using the pure culture of serum albumin, serum globulin and the activities of Aspergillus parasiticus MTCC 1894 (Microbial Type gamma glutamyl transferase (GGT), alanine amino Culture Collection and Gene Bank, IMT, Chandigarh, transferase (ALT) using automatic analyzer India) grown on potato dextrose agar.Then AF (Boehringer Mannheim Hitachi 704 automatic produced on relevant Medias were extracted [11] and analyzer, Japan).The methodology and the set of quantified by thin layer chromatography [12].
reagents used in respect of each parameter were as per Individual ingredients were screened for mycotoxin the recommendations of the manufacturer of the content prior to compounding the feed.Compounded analyzer system.Data are presented as means of each feed was analyzed for the presence of AF before treatment.The serum samples were assayed for including the rice and wheat culture materials, and then antibody titers against Newcastle disease (ND) and the diets were prepared by incorporating required infectious bursal disease (IBD) using ELISA technique quantities (0.5 ppm) of rice/wheat culture containing at five weeks of age.Treatment-wise means of titers AF into the diet.To the basal diet High-grade bentonite were calculated.at 0.5, 0.75 and 1.00 percent were added to prepare the different experimental diets.Compounded experimen-Statistical analysis: The results were subjected to onetal diets were analyzed for mycotoxin content to way analysis of variance.Means were compared using counter check the required levels.Chicks were fed ad Tukey method [14].The level of significance was libitum.Feeding of test diets commenced at zero day of tested (P<0.05).age and continued till the termination of experiment at

Results and Discussion
five weeks of age.
Growth performance: Birds fed on aflatoxin Data collection: Body weight and feed intake were doi:10.5455/vetworld.2013.313-317Table-1.Percent ingredient composition of basal diet contaminated feed (0.5 ppm) showed a significant bentonite against AF induced organ weight increase in (P<0.05)decrease in body weight, feed intake and broilers were in accordance with [20,21,30].Compared increased FCR.The result of present investigation was with control, relative weights of gizzard and pancreas in accordance to the observations of [15][16][17][18][19].
were not affected either in AF fed group, control and The addition of 0.75 and 1.0 per cent HGB HGB supplemented groups.The relative thymus significantly restored the body weight, feed intake and (38.99%) and bursal weights (31.36%) were FCR (Table -2).The present results relating to the use of significantly (P<0.05)lower at 0.5 ppm inclusion of Bentonite in AF containing diets is in agreement with AF group (Table -3) compared to control diet.A Similar the findings of [20][21][22] who opined that improvement reduction in relative weights of thymus and bursa with in body weight upon bentonite inclusion may be due to AF were reported by [4,17,27,28].their montmorillonites content that bind irreversibly Relative weights of thymus and bursal were not with toxin in the gut and thereby preventing absorption altered by supplementation of varying levels of HGB of the toxin across the intestinal wall, providing a compared to control diets.Compared with control, prophylactic action.relative weight of spleen was not affected either in AF High mortality rate of 14.20 per cent was fed group or HGB supplemented groups.The observed in group fed with diet containing 0.5 ppm AF.
protective effects of HGB may be due to sequestration Similar mortality rate in broilers due to AF toxin were of AF in the gut which reduces bioavailability of the AF reported by several workers [17,[23][24][25][26]] Mortality rate toxin.was reduced considerably in control as well as in the Serum Biochemistry: The Serum antibody titres against groups supplemented with 0.5, 0.75 and 1.0 per cent ND and IBD vaccination were significantly (P<0.05)HGB. who reported.The results were in accordance depressed by aflatoxin which were restored with the with the findings of [20], who reported a significant inclusion of 1.0 per cent HGB (Table-4).These reduction in mortality of broilers upon addition of 0.5 findings agree with the previous reports of decreased per cent bentonite to 0.5 ppm aflatoxin containing antibody titres against ND and IBD in AF fed broilers diets.
[31, 32, 33, 34].The decreased antibody titers could be Organ weights: The relative weights of liver (19.56%), due to inhibition of DNA and protein synthesis by and kidney (18.38%) increased significantly (P<0.05)aflatoxin through impairment of amino acid transport with addition of 0.5 ppm AF (Table -3 The results clearly demonstrated the protective kidney weights were in accordance with the findings of effects of bentonite at 1.0 per cent inclusion to aflatoxin [17-19, 27, 28] ), whereas and m-RNA transcription resulting in lowered level of improvement was observed with dietary inclusion of antibody production[35].0.75 and 1.0 per cent HGB.The increase in liver and

Table - 3
. The increase in liver weight could be diet in chickens.The findings of present study were attributed to increased lipid deposition in liver due to comparable to the reports of [36] who reported an impaired fat metabolism [29].The protective effects of improved antibody titres in chickens fed on aflatoxin. .Effect of aflatoxin with or without High grade bentonite (HGB) on organ weights (g/ kg live wt.) and lymphoid organ th weights of broiler chickens at 5 wk of age (Mean+ SE).Tyczkowska, K. and Hamilton, P. B. (1984) concentration of uric acid and albumin were not Simultaneous Occurrence of Deoxynivalenol, Zearalenone affected either in AF fed group or HGB supplemented and Aflatoxin in 1982 Scabby Wheat from Midwestern groups (Table 5).Reduced levels of serum total protein, United States.Appl.Environ.Microbiol.47:151-154.serum uric acid and serum albumin in AF fed diets were 4. Devegowda, G. (2002) Mycotoxins: Economic risks and their control.In: Handbook of Poultry Nutrition.Published reported earlier [23, 27, 29].by American Soybean Association, pp.246-260.The activity of serum GGT significantly doi:10.5455/vetworld.2013.313-317Table-5.Effect of aflatoxin with or without High grade bentonite (Ashafeed) on levels of serum biochemical parameters and th serum enzyme activities of broilers at 5 wk of age (Mean SE).+