MYCOTOXINS IN AQUACULTURE

Transcription

1 MYCOTOXINS IN AQUACULTURE OCCURRENCE AND IMPACT IN RAINBOW TROUT Rui A. Gonçalves BIOMIN Holding, Austria 2017 by Erber AG, Austria. All rights reserved. Naturally ahead

2 2017 by Erber AG, Austria. All rights reserved. What are mycotoxins? Storage fungi Aspergillus sp. Aflatoxin (AF) Ochratoxin A (OTA) Penicillium sp. Ochratoxin A (OTA) Field fungi Fusarium sp. Deoxynivalenol (DON) Zearalenone (ZEN) Fumonisin (FUM) Naturally ahead

3 Effects of mycotoxins depend on:, - and -related factors toxin- animal environmental Farm management (hygiene, humidity, temperature, etc) Age, sex and species Duration of exposure Nature and level of mycotoxin concentration Other toxic entities Nutritional and health status 2017 by Erber AG, Austria. All rights reserved. Naturally ahead

4 Mycotoxins - Easy ways to remember Aflatoxins Zearalenone Thrichotecenes Fumonisin DON, T-2 Carcinogenic Toxic to liver (hepatopancreas) growth, performance and feed efficiency Strong immune suppressor Source: Estrogenic compound Fertility & Reproductive problems Affects growth Protein synthesis Feed intake growth, performance Immune suppressors Lipid synthesis Neurotoxin performance Immune suppression 2017 by Erber AG, Austria. All rights reserved. Naturally ahead

5 Mycotoxin Occurrence 2017 by Erber AG, Austria. All rights reserved. Naturally ahead

6 2017 by Erber AG, Austria. All rights reserved. Global Results January March 2017 Afla ZEN DON T-2 FUM OTA Number samples tested Average of positive (µg/kg) Maximum (µg/kg) Naturally ahead

7 2017 by Erber AG, Austria. All rights reserved. Europe Afla ZEN DON T-2 FUM OTA Number samples tested Average of positive (µg/kg) Maximum (µg/kg) Naturally ahead

8 2017 by Erber AG, Austria. All rights reserved. North America Afla ZEN DON T-2 FUM OTA Number samples tested Average of positive (µg/kg) Maximum (µg/kg) Naturally ahead

9 2017 by Erber AG, Austria. All rights reserved. South America Afla ZEN DON T-2 FUM OTA Number samples tested Average of positive (µg/kg) Maximum (µg/kg) Naturally ahead

10 Which Plant proteins? Corn Afla ZEN DON T-2 FUM OTA Number samples tested Average of positive (µg/kg) Maximum (µg/kg)

11 Which Plant proteins? Soybean Meal Afla ZEN DON T-2 FUM OTA Number samples tested Average of positive (µg/kg) Maximum (µg/kg)

12 Which Plant proteins? Wheat Afla ZEN DON T-2 FUM OTA Number samples tested Average of positive (µg/kg) Maximum (µg/kg)

13 Which Plant proteins? Wheat Bran Afla ZEN DON T-2 FUM OTA Number samples tested Average of positive (µg/kg) Maximum (µg/kg)

14 Impact of DON in rainbow trout (Oncorhynchus mykiss) Short term exposure/high Dosage 100 fish (14.10 ± 0.05 g) 85 L aquaria: 15 fish per aquarium Flow-through system Temp. =15.47 ± 0.14 C; oxygen of 8.73 ± 0.12 mg l -1 ; ph at 7.53 ± 0.04 NH 3+ /HH 4 at 0.0 ± 0.0 mg l -1. Fed 3 times per day near satiety Duration: 50 days Challenge test Y. ruckeri High dosage Low dosage Short term exposure Long term exposure Feeding groups: [Control] Standard feed [1.1 DON] Standard feed contaminated with 1,166 µg kg -1 DON [2.7 DON] Standard feed contaminated with 2,745 µg kg -1 DON

15 Impact of DON in rainbow trout (Oncorhynchus mykiss) Long term exposure/low Dosage 200 fish (89.90 ± 0.20 g) 500 L tanks: 25 fish per aquarium (quadruplicate) Flow-through system Temp. =18.15 ± 0.20 C; oxygen of 9.73 ± 0.15 mg l -1 ; ph at 7.54 ± 0.03 NH 3+ /HH 4 at 0.0 ± 0.0 mg l -1. Fed 3 times per day near satiety Duration: 168 days Vaccination (IP) efficiency against Y. Ruckeri High dosage Low dosage Short term exposure Long term exposure Feeding groups: [Control] Standard feed [DON] Standard feed contaminated with 367 µg kg -1 DON

16 Impact of DON in rainbow trout (Oncorhynchus mykiss) µg g High dosage Short term exposure Analyte Value Found Analyte Value Found Major Mycotoxins Fusarium metabolites Aflatoxin B1 Not detected 15-Hydroxyculmorin Zearalenone Culmorin Deoxynivalenol Not detected Equisetin T-2 Toxin Not detected Fusaric acid Fumonisin B1 Not detected Penicillium Toxins Fumonisin B Brevianamid F Fumonisin B Mycophenolic acid Ochratoxin A Not detected Rugulusovin Sum of Ergot alkaloids 0.72 Aspergillus Toxins Zearalenone-Derivates Tryptophol Zearalenone-sulfate Other metabolites Cyclo(L-Pro-L-Val) 1, Cyclo(L-Pro-L-Tyr) 2, Deoxynivalenol Added Analysed Control DON 1,500 1,166 ± DON 3,000 2,745 ± 330

17 Impact of DON in rainbow trout (Oncorhynchus mykiss) 0.98 FCR High dosage Short term exposure g/fish Control LD Don HD Don Feed intake Control LD Don HD Don Thermal-unit growth coefficient Control LD Don HD Don

18 Impact of DON in rainbow trout (Oncorhynchus mykiss) LDH (IU L -1 ) ALT (IU L -1 ) AST (IU L -1 ) High dosage Short term exposure Control ± a ± 7.66 a ± 2.36 a 1.1 DON ± a ± 0.97 a ± a 2.7 DON ± a ± 9.88 b ± b 1-way ANOVA p-value <0.001 <0.001

19 Impact of DON in rainbow trout (Oncorhynchus mykiss) Clinical signs High dosage Short term exposure Slight hemorrhage in abdominal cavity Slight Rectal hemorrhage/irritation

20 Impact of DON in rainbow trout (Oncorhynchus mykiss) Challenge test Y. ruckeri High dosage Short term exposure 100% 95% a 90% 85% a b Survival 80% 75% 70% 65% 60% 55% 50% DoI Control b 1.1 DON 2.7 DON Days after infection

21 Impact of DON in rainbow trout (Oncorhynchus mykiss) Low dosage Long term exposure Final body weight (g) CTRL DON Day 0 Day 37 Day 62 Day 92 Day 125 Day 168

22 Impact of DON in rainbow trout (Oncorhynchus mykiss) Feed conversion ratio CTRL DON Day 37 Day 62 Day 92 Day 125 Day Low dosage CTRL Long term exposure DON Optical density Vaccinated Unvaccinated Vaccinated Unvaccinated SGR (%/Day) Day 37 Day 62 Day 92 Day 125 Day 168 Control Mycotoxins

23 Conclusion Fusarium mycotoxins are the main toxins found Globally: 80% of samples DON 71% of samples FUM 56% of samples ZEN 30% of samples AF Co-occurrence of 76% Plant meals used for Salmonids: Corn 82%DON; 89%FUM; 53% ZEN Soybean 83%DON; 78% ZEN ; 50% AF, 24% FUM Wheat 76% DON, 49% ZEN; 44% AF Wheat bran 97% DON; 71% ZEN; 62% AF; 58% OTA

24 Conclusion Occurrence and Co-occurrence in plant meal by-products Wheat vs wheat bran Co-occurrence 61% 78%

25 Corn samples 2015 Gonçalves et al., 2017 v v Co-occurrence - Asia 3% 22% 75% <limit of detection 1 mycotoxin more than 1 mycotoxin Co-occurrence - Europe 7% 50% 43% Nt Analysis HPLC ELISA nasia neurope Corn

26 Corn Gluten Meal samples 2015 Gonçalves et al., 2017 Average value corn Co-occurrence - Asia 100% <limit of detection 1 mycotoxin more than 1 mycotoxin Co-occurrence - Europe 9% 91% Nt Analysis HPLC ELISA nasia neurope CGM

27 Conclusion Short term exposure Ingestion of DON by trout at 1,166 µg kg -1 and 2,700 µg kg 1 clearly impacted growth performance and enzyme parameters. Histopathology has shown mild to moderately changes in liver but not in remaining sampled tissues. Despite the impact in previous described parameters, no consequences were observed regarding the susceptibility of trout to Y. ruckeri. Ingestion of 367 µg kg -1 of DON negatively impacted clearly impacted growth performance. Experimental results confirm that rainbow trout is sensitive to DON, masked clinical symptoms Long term exposure High levels of individual variability within the fish fed DON, suggesting that the individual immune/nutritional status of each animal influence greatly the DON susceptibility

28 Thank you for your attention! Rui A. Gonçalves BIOMIN Holding GmbH