Rising temperatures and humidity levels signal the risk of facial eczema (FE) and will have farmers reaching for their zinc treatment to prevent this dreaded disease.
To harness the power of this mineral it’s important to start dosing well before the spores become active. SealesWinslow Science Extension Officer Natalie Hughes explains why timing is such a crucial factor.
With rising fungal spore counts in pasture, the risk of facial eczema outbreaks among grazing animals dramatically increases, even with only low levels of consumption over longer periods. In the absence of adequate protection, the ingestion of those spores leads to well-known FE symptoms such as liver damage, photosensitivity, reproduction issues, weight loss and a drop in milk production.
Given that every clinical case of this potentially devastating disease represents up to 23 sub-clinical cases1 in a herd, it’s vital to address the problem. There’s no cure for cows once they have developed the disease – you can merely provide some relief with measures such as taking the animals out of the sun. With this in mind, effective prevention takes on a whole new meaning – and that’s where zinc comes to the fore.
“Zinc protects the liver by mopping up free radicals like a sponge – hence, the widespread use of this trace mineral,” says Natalie.
However, she emphasises one big factor that governs zinc’s effectiveness. “Zinc levels take a while to build up so the most important thing is to start dosing early. Zinc can only work once adequate levels have accumulated in the body.” Natalie recommends starting two to three weeks before spore counts start to rise, suggesting supplementation may be required around early December if weather conditions are warm and humid.
A successful zinc dosing regime also needs to address zinc’s specific properties. It’s important to start with low doses to help offset the inherent unpalatability of zinc. Higher concentrations of zinc added to water troughs can lead to lower water intake, resulting in reduced milk production. A product such as SealesWinslow’s Zincmax+ includes peppermint in the formulation to offset the bitter mineral flavour.
Another aspect to consider is that when given at full preventative dose for facial eczema, zinc can reduce the animal’s absorption of copper. Zincmax+ addresses this undesirable side effect with the addition of chelated copper. This form of copper is attached to a protein, meaning it’s highly available and can be readily absorbed into the body. It’s an effective way to maintain healthy copper levels.
The benefits of a timely zinc dosing regime are compelling. When you consider the potential costs associated with a facial eczema outbreak, it’s clear the extra dosing task in early summer is well worth the effort. Once the spore count rises, nothing else will guard against it.
1. DairyNZ Facial Eczema – Management for New Zealand Dairy Herds (www.dairynz.co.nz/animal/health-conditions/facial-eczema/)
For more information, contact your local Farm Source TSR or visit your nearest Fonterra Farm Source store.
Article supplied by SealesWinslow