Efficacy of Bacillus subtilis ANSB060 Biodegradation Product for the Reduction of the Milk Aflatoxin M1 Content of Dairy Cows Exposed to Aflatoxin B1

Abstract

This study was conducted to determine the effect of Bacillus subtilis ANSB060 biodegradation product (BDP) in reducing the milk aflatoxin M1 (AFM1) content of dairy cows fed a diet contaminated with aflatoxin B1 (AFB1). Twenty-four Chinese Holstein cows (254 ± 19 d in milk; milk production 19.0 ± 1.2 kg d−1) were assigned to three dietary treatments, as follows: (1) control diet (CON), consisting of a basal total mixed ration (TMR); (2) aflatoxin diet (AF), containing CON plus 63 μg of AFB1 kg−1 of diet dry matter; and (3) aflatoxin diet plus BDP (AF + BDP), containing AF plus BDP at 0.2% of diet dry matter. The experiment lasted 12 days, including an AFB1-dosing period from days one to eight, followed by a clearance period from days nine to twelve. Milk samples were collected on days 2, 4, 6, and 8–12, and the plasma was sampled on day 9, before morning feeding. Short-term AFB1 exposure did not affect the milk production and composition. The plasma biochemical indices, except for lactic dehydrogenase (LDH), were also not changed by the AFB1 intake. The plasma LDH level was significantly elevated (p < 0.05) following dietary treatment with AFB1, while no significant difference was observed between the AF + BDP and CON treatments. Adding BDP to the AFB1-contaminaed diet resulted in a significant reduction in AFM1 concentration (483 vs. 665 ng L−1) in the milk, AFM1 excretion (9.14 vs. 12.71 μg d−1), and transfer rate of dietary AFB1 to milk AFM1 (0.76 vs. 1.06%). In conclusion, the addition of BDP could be an alternative method for reducing the dietary AFB1 bioavailability in dairy cows.

Enhancing the Utilization of Palm Leaf Hay Using Bacillus subtilis and Phanerochaete chrysosporium in the Diet of Lambs Under Desert Conditions

“…B. subtilis and P. chrysosporium at 4 g daily increased serum total protein, globulin, and urea-N levels, indicating enhanced nutrient utilization and suggesting unaltered kidney function and minimal protein catabolism in muscles (Hosten, 1990). Our results are consistent with the results of Guo et al (2019) who observed that inclusion of B. subtilis in the diets of lactating cows exposed to aflatoxin B1 did not affect blood parameter levels.…”

Adsorbents Reduce Aflatoxin M1 Residue in Milk of Healthy Dairy Cow Exposed to Moderate Level Aflatoxin B1 in Diet and Its Exposure Risk for Humans

“…The milk AFM 1 content continued decreasing and was ultimately undetectable by 5 days after stop administrating AFB 1 . This was consistent with previous studies that the duration of AFM 1 clearance in the milk of dairy cows could be 3 [ 2 , 33 , 43 ] to 4 days [ 17 ] after the last critical risk (>20 µg/kg) AFB 1 administration. These findings suggested that moderate risk AFB 1 (8 µg/kg) administration has a similar effect tendency to AFM 1 content in milk of apparently healthy dairy cows with a critical level (>20 µg/kg) AFB 1 administration.…”

“…All the cows in the four dietary treatments were in apparently healthy condition and there were not any clinical signs of aflatoxicosis observed throughout the entire feeding trail. The previous studies indicated that critical level of (≥20 µg/kg) AFB 1 : 20 µg/kg [ 2 , 19 ], 40µg/kg [ 2 ], 63 µg/kg (1197 µg/d) [ 17 ], 75 µg/kg (1725 µg/d) [ 33 ], 100 µg/kg [ 41 ], 117 µg/kg [ 37 ], 112 µg/kg [ 38 ] and adsorbents administration in diet had no significant effects on the production performance of dairy cows. However, Queiroz et al [ 43 ] and Malinee et al [ 32 ] reported that cows were exposed to naturally contaminated diets containing 22.28 µg/kg AFB 1 resulted in a significant reduction of milk protein concentration and milk fat yield.…”

“…While alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total protein (TP) are the main liver function parameters of dairy cows, there were no statistically significant differences in ALT, AST and TP content among each dietary treatment in the current study. Likewise, both short-term addition of critical risk level (63 µg/kg) and long-term addition of critical risk level (20 µg/kg) AFB 1 in the diet of cows did not cause statistically significant changes in ALT, AST and TP [ 17 , 19 ]. Meanwhile, Keller et al (2015) reported that the yeast cell wall extracts and sodium alginate in adsorbent might stimulate both nonspecific and specific immunological responses, thus improving the performance of cows [ 51 ].…”

“…Biomin Inc. (Ferndale, MI, USA) conducted a worldwide survey of mycotoxin contamination in feed ingredients in 2018 [ 27 ] and 2019 [ 28 ], the results showed that the aflatoxin positive rates of finished feed in Asia were 44% and 30%, respectively, and the median of positive samples were both 8 µg/kg [ 29 ]. Meanwhile, most researchers conducted the field trails in a critical high level of (>20 µg/kg) AFB 1 dosages from 20 µg/kg [ 19 , 30 , 31 ], 22.28 µg/kg (naturally contaminated) [ 32 ], 40 µg/kg [ 31 ], 63 µg/kg [ 17 ], 76 µg/kg (1725 µg/d) [ 33 ], 100 µg/kg [ 34 , 35 ], 120 µg/kg [ 36 ] and up to 300 µg/kg in diet to investigate their negative effects to the cows [ 34 ]. Furthermore, there were no field trials that estimated the human exposure risk to milk AFM 1 residue before.…”