Supplements For Animals Are Better Researched Than Those For People

I was looking through a health magazine recently and noticed an ad for a product that “provides all your daily vitamin, mineral, trace element and micronutrient needs in one pill”. I counted nearly sixty different ingredients that each pill was meant to contain. Being averse to eating greens and salads since a lad, and being an inconsistent eater anyway, I wondered if this could this be the answer to the dire nutritional deficiencies my mother always warned me about?

Intrigued, I phoned the company and asked what form and level of the various ingredients were contained in each pill. That’s when things got confusing! Try as I might, I couldn’t get a straight answer as to how much selenium, copper, iodine, vitaminB12, or whatever, was actually in the pills, nevermind their chemical form. Amid a babble of information that included the words, “natural, “organic”, sourced from the sea”, “ionic”, and “total replenishment”, I concluded that there was no rationale, quality control, or basic science behind the product. Nothing of consequence told me exactly what really was in the product, or at what concentration, or why it might be good for me.

This conversation confirmed for me that most nutritional supplements available for our animals are far better researched and scientifically supported than those promoted for humans. I reckon male bovine defaecatory material is rife in the human nutritional product market!! And the resultant cow-pat is damned expensive compared to what it is!!

I then reflected on the nutritional supplements available for animals in New Zealand. Basically, they tend to come in two forms. Those that provide a bit of everything (like the human product mentioned above), and those that deliver just one or more specific nutrients at specific amounts with a rationalised justification..

The problem with products that suggest they provide a total answer to the trace element needs of any farm or herd, is that they ignore the fact that each farm usually has different requirements. In my opinion, no single nutritional formulation can meet the real needs of every farm and its animals. This particularly applies to products that include copper, selenium, and iodine, along with other micro or macro minerals.

In a recent article I discussed why virtually each farm has a different requirement for copper supplementation. This is because the differences in levels of antagonists like molybdenum, iron and sulphur, and any previous copper supplementation policies on a farm, can significantly affect a herd’s real needs for copper. A daily intake of about 90mg/Cu/cow/day may be fine on one farm, but may be way too low on an adjoining property. You should supplement copper according to the actual needs of the cattle on a property, and in a way that allows for flexibility of dose. If you use a daily trace mineral supplement that contains copper plus other trace minerals, consider a form that lets you add in additional compatible copper to the mix, should this be necessary.

Some combination products include selenium in their formulation with a fixed dosage recommendation. Again, the selenium provided may be too low compared to a herd’s real needs. As with copper, it is best to first establish your herd’s actually selenium needs and then supplement with a form of selenium that allows for flexible dosing. The amount of selenium a herd needs daily for optimum benefit can vary between 0.5mg-2mg/cow/day. Blood analysis and local knowledge is usually needed to determine optimum intake requirements..

Iodine is the third trace element that should be supplemented according to herd requirements rather than to any general recommendation. Iodine levels in pasture vary quite widely in New Zealand, but more importantly, our pastures contain high levels of goitrogens, plant substances that inhibit the absorption and utilisation of dietary iodine. White clover is especially high in goitrogens, particularly around springtime, while brassica crops are low in iodine and also contain goitrogens.

Blood thyroxine or T4 levels give some indication of the iodine status of cattle, but should be interpreted with caution, as this thyroid hormone’s production is suppressed during early lactation and can appear artificially raised if there is a concurrent selenium deficiency. Iodine can be supplemented at rates of between 7.5 - 50 mg/cow/day, the higher rates being more necessary for lactating cows grazing pasture high in goitrogens.

It would be nice if trace element supplementation were a simple and straightforward issue so that we could select just one product and know that it contained everything our animals needed. Unfortunately, this can never be the case and it does pay to keep a monitor on your herd’s real requirements through pasture, blood, and liver analyses, and then supplement as necessary with mineral products that allow for flexibility of dosage levels. But compared to some of the hype that accompanies human nutritional supplements, I reckon animals get a much more rational and value for money deal from the supplements that are available for them.