Mycotoxin in Dairy Cattle

Thanks a lot Dr.Lon Whitlow and W.H.Hagler for wonderful article about mycotoxin effects in dairy cattle.You have explained the critical and complex topic in very simple way.

The feedback below is specifically from my Indian Experiences (since 1991)

In Cattle, mycotoxins over prolonged exposure at possibly high levels can cause some adverse impact though I am not aware of classical experimental studies or field observations on the same. The most organised Dairy farms in Northern India also do not use any toxin binder in Cattle feed. As much as nutrients get degraded in rumen contents and bacteria, toxins do undergo changes that can possibly render them less toxic or even non-toxic. Unless we study in fistulated animals the fate of known level of toxins fed over a period of time, its very difficult to pinpoint the impact of mycotoxins in Cattle.

While there is no doubt that we should avoid feeding poor quality feed ingredients to Cattle, lot more further studies at field level to be carried out.

I do agree with Rajesh but the extent and accuracy is subjective to predict or quantify through any such studies otherwise it would have already been done to the extent of driving the marketing the concepts. The reason is that there are so many permutations and combinations possible for mycotoxins present, as feed is a combination of plant products of various origin depending upon the price trends, season etc. That is the reason why various Mycotoxin binders are so holistic in composition, probably to control (not prevent) the maximum range of mycotoxins for max number of species. Most formulations hover around HSCAS with Aflatoxin being the main culprit. Companies add frills to it e.g. activated charcoal, enzymes, anti- fungals, MOS, dry yeast, oregano derivative, herbs etc. to woo the customers and build USPs for product cycle. Also, it is more the origin country of the product and extent of marketing gimmicks that decides its price and market share, and has left in a psychological market segment for the moment.

Absolutely informative article as it clarifies some of the grey areas regarding the use of aflatoxin contaminated feeds to different classes of livestock. The issue of a testing framework within the dairy industry for smallholders in the tropics is quite evident due to traceability challenges. Aggregating farmers into milk bulking groups could be an opportunity but more crucially there is need to assess the opportunities of creating motivating producers to reduce levels of Aflatoxin M1

The occurrence of Aflatoxin in forages was probably more associated with grain and seed residue in the samples, as Aspergillus tend to prefer a starchy material to grow where as the Fusarium sp will grow on the pasture, and is present in over 85% of the samples tested over a 5 year period.
Another interesting from further research was that 100% of all cattle tested in SW Victoria all were positive for zearalenone, and derivatives and there is no major fertility issue there, and some samples of pasture have reached 70ppm ZEA. However it is still my personal belief that the biggest mycotoxin problem facing cattle production is still related to the ergot alkaloids, in particular perennial rye grass and tall fescue, and even paspalum in the more tropical regions. However the biggest issue with this is educating people of the causes etc and the impact of these toxins.
AfB1 is still a major problem and work from Turkey even suggests that levels as low as 5ppb can impact on fertility, cystic ovaries and lameness.
Cheers Damian