Transfer of dietary aflatoxin B1 to milk aflatoxin M1 and effect of inclusion of adsorbent in the diet of dairy cows

Abstract

The objectives of this study were to investigate the transfer of aflatoxin from feed to milk and to evaluate the effects of Solis Mos (SM; Novus International Inc., St. Charles, MO) on milk aflatoxin M1, plasma biochemical parameters, and ruminal fermentation of dairy cows fed varying doses of aflatoxin B1 (AFB1). Three groups of 8 multiparous Holstein cows in late lactation (days in milk = 271 ± 29; milk yield = 21.6 ± 3.1 kg/d) were assigned to 1 of 3 experiments in a crossover design. Cows in experiment 1 received no aflatoxin, cows in experiment 2 received 20 µg of AFB1/kg of dry matter, and cows in experiment 3 received 40 µg of AFB1/kg of dry matter. Cows in each experiment were assigned to 1 of 2 treatments: control or 0.25% SM. Each experiment consisted of 2 consecutive periods with the first 4 d (d 1 to 4) as adaptation, followed by AFB1 challenge for 7 d (d 5 to 11), and finally clearance for 5 d (d 12 to 16) in each period. Samples of total mixed ration and milk were collected on d 1, 2, and 10 to 14 of each period. Blood samples were collected from the coccygeal vein on d 1, 11, and 14 of each period. Rumen fluid was collected by oral stomach tube 2 h after the morning feeding on d 1 and 11 of each period. Adding SM to basal or AFB1-contaminated diets at 0.25% had no effect on lactation performance, liver function, or immune response. However, addition of SM improved antioxidative status, as indicated by increased plasma concentrations of superoxide dismutase and reduced malondialdehyde regardless of dietary AFB1 level. Addition of SM to the AFB1-free diet eliminated the background AFM1 in milk and increased total ruminal volatile fatty acid (99.6 vs. 94.2 mM) concentrations. Adding SM to the AFB1-contaminated diet in experiment 2 decreased the AFM1 concentration (88.4 vs. 105.3 ng/L) and the transfer of aflatoxin to milk (0.46 vs. 0.56%), and increased total volatile fatty acid concentration (99.8 vs. 93.4 mM). Adding SM to diets with 40 µg/kg of AFB1 did not elicit changes in rumen parameters or AFM1 output. These results indicated that adding SM to diets containing 0 or 20 µg of AFB1/kg decreased milk AFM1 concentration, improved antioxidative status, and altered rumen fermentation, whereas adding SM to a diet containing 40 µg of AFB1/kg did not reduce AFB1 transfer but did increase the antioxidant status of the liver.

Effects of calcium montmorillonite clay and aflatoxin exposure on dry matter intake, milk production, and milk composition

“…Specifically, transfer rate was reduced from 1.07% with the AF diet to 0.52% and 0.32 ± 0.08% with the inclusion of NSP at 0.58% and 1.17% of DMI. Similar transfer rates have been reported for dairy cows consuming AFcontaminated diets (Harvey et al, 1991;Xiong et al, . Because of reduced transfer rate, total excretion of AFM 1 was also reduced (P < 0.01) in a dose-dependent manner.…”

“…Recent drought conditions in the United States have led to greater risk for preharvest AF contamination of crops destined for animal feed (Cotty and Jaime-Garcia, 2007;Guo et al, 2008); therefore, it is necessary to evaluate practical and inexpensive strategies to mitigate AF content in animal feed and animal products. Examples of feed additives that have been reported to decrease the bioavailability of AF from contaminated dairy rations include yeast-derived products (Firmin et al, 2011), clays such as Na and Ca bentonite (Diaz et al, 2004), or combinations of yeast products with clay (Kissell et al, 2013;Xiong et al, 2015). Of these products, montmorillonite clays have yielded the best results, particularly a hydrated calcium montmorillonite available under the trade name NovaSil and NovaSil Plus (NSP; Phillips et al, 1988;Harvey et al, 1991;Phillips et al, 2008Phillips et al, , 2002Kutz et al, 2009).…”

Chemical, physical and technological properties of milk as affected by the mycotoxin load of dairy herds

“…According to Korosteleva et al (2007) milk composition was not affected by a diet containing DON. Similar findings were reported for DON + ZEA (Winkler et al, 2014) or AFL (Xiong et al, 2015). Kiyothong et al (2012) did not find significant differences in fat, lactose, and solids-non-fat after supplementation of MSAs to multi-mycotoxin (DON, FB1, ZEA, OTA, AFL, and T-2 toxin) contaminated diet, but they reported a positive influence of MSAs on milk protein concentration (P < 0.05) and also noted that milk fat percentage tended to be higher for MSA-supplemented than for non-supplemented cows.…”

“…On the other hand, in a subsequent study, Takagi et al (2013) did not observe significant correlations between an individual cow's urinary ZEA concentrations and SCC. Similarly, SCC was not affected by a diet containing DON (Korosteleva et al, 2007) or AFL (Xiong et al, 2015). There are some studies focused on the effect of various types of MSAs on SCC assuming that MSA supplementation can ameliorate the adverse effects of mycotoxins on animal immunity system.…”

Detection of Aflatoxin Contamination of Dairy Production Chain in the Northwest Region of Rio Grande do Sul, Brazil

“…When added to the feed, such products are intended to bind to mycotoxins in order to transport them fully or partially out of the digestive tract, thereby preventing the absorption and intoxication of the animals (Kabak et al, 2006;Xiong et al, 2015;Nidhina et al, 2017). However, the use of inorganic adsorbents may reduce the nutrient density of the diet, as well as promote an excess of absortion capacity that may lead to a decrease in the availability of important microelements (Rabiee et al, 2010).…”