Molds in Pet Food, Zearalenone

You don’t need vampire movies, because there’s real life horror tales in food.  For the next few Caring for Pet blog entires, let’s discuss molds that may be present in food commercially available for dogs, cats, cattle, hogs and horses.

Tomorrow, I’m going to see 11-year-old Mina who has developed a swollen vulva. So, let’s start our series on molds in pet foods with Zearalenone.

Zearalenone is found in corn, wheat, rice, sorghum, maize--grains common in many pet foods. Zearalenone is also found in bread.  It causes estrogenism. Pigs are highly sensitive to zearalenone, and it causes infertility and abortion. Farmers suspect zearalenone mycotoxicosis when pigs develop early puberty, or swollen vulvas,  but are infertile. If the farmer's pregnant sows eat aearalenone-contaminated food, the piglets may be mummified, stillborn, or born with swollen vulvas and splay legs.

Dogs are also sensitive to Zearalenone, but are not as severely affected as pigs are. The following abstract from Polish Journal of Veterinary Science 2004;7(1):59-66. 74 Refs. discusses effect of oral Zearalenone on bitches.

 Zearalenone applied per os provides adverse effects in structure of chosen parts of bitch reproductive system

M Gajecka1; E Jakimiuk; M Polak; I Otrocka-Domagała; T Janowski; W Zwierzchowski; K Obremski; L Zielonka; J Apoznański; M Gajecki

1Division of Veterinary Prevention and Feed Hygiene, Department of Veterinary Health Protection, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Poland. gajecki@uwm.edu.pl

Article Abstract

Both earlier investigations and complete formulas of pet food for dogs show that professionally prepared pet food is based in 30% on the material of the plant origin. Our own investigations prove that animal feeding stuffs of the plant origin are very often vectors of many undesirable substances (including micotoxins) that are unfavourable for carnivores. Zearalenone is a micotoxin, which frequently occurs among them. It was revealed in pet food in quantities from 5.0-299.5 microg/kg. It is a very dangerous xenobiotic because of its quick and easy absorption in the organism after per os application in monogastric animals. It is also a sterid and despite its plant origin it binds estrogen receptors in the reproductive tract and causes its hypo- and dysfunction. It is clearly visible in young, growing organisms and those during the menopause. In bitches, dysfunctions of the reproduction system, such as: endometritis-pyometra syndrome, prolonged oestrus, ovarian cysts and others are often found. It is supposed that specific for this species hormonal regulation of the reproduction processes based on the long progesterone and prolactin cycles, and on high sensibility to estrogens plays an important role in the etiopathogenesis of these dysfunctions. The application of hormones in bitches in therapeutic and biotechnical (contraception) purposes are the other factors, which should be taken into account in this aspect. There are some suggestions that therapeutic management, unfortunately connected with mistakes in the medical art, is often a cause of pathological condition in a reproductive organ in bitches. However, another reason of these disorders may be that bitches take zearalenone with the commercial pet food. The long-lasting intake of the feed with a low dose of this micotoxin may be the factor, which complicates hormonal regulation of the reproduction processes and is the cause of many disorders. Our own pilotage investigations showed that application of zearalenone at a dose of 200 microg/kg b.w. for 7 days leads to apoptotic-like changes in granule cells in the bitch reproductive system, atresia of follicular cells and oedema and hyperplasia of the oviductal and uterine cells. They could also indicate a follicular phase of the oestrus cycle in bitch. However, it did not take place.

 

When I see Mina the little Yorkie with a swollen vulva, tomorrow, I’ll be looking for possible  foreign body, bladder infections, urinary crystals, Cushing’s disease, and estrogen toxicity from zearalenone exposure. An exam, blood and urine tests will help eliminate the first four, but eliminating zearalenone exposure may be an impossible task.