WildAgain Wildlife Rehabilitation, Inc.
Click here for test results on the powdered milk replacer products
Summary of the 8 products tested in March 2012
WildAgain continues testing milk replacement products that wildlife rehabilitators feed to juvenile wild mammals. Eight powdered milk replacement products have been added to WildAgain's growing database of test results included on this website. Test results of the products (Fox Valley® 40/25, 20/50, 25/30, 32/40; PetAg's® KMR; and Petsmart's GNC® Puppy Milk Replacer) are included on milk replacer research page and in WildAgain's Nutrition Calculator (except for KMR which is awaiting independent lab testing). Tests are in process on additional milk replacement products, including Esbilac®, KMR® and Zoologic® 32/40. The results of the recently completed tests are summarized below and include the following:
- Fox Valley® products (FV40/25 Lot#021941, FV40/25 Lot#022491, FV40/25 Lot#020261, FV20/50 Lot#042721, FV25/30 Lot#051391, FV32/40 Lot#011471) have some issues with Guaranteed Analysis Minimums and Maximums; solubility (reconstitution) of the products is improved using hotter temperature water and allowing at least 4 hours to reconstitute; and disclosure of product ingredients is inconsistent between the package labeling and the manufacturer's website.
- KMR® (Lot#HG0171K) continues solubility issues when mixed as per label instructions, and performs much better with hotter water temperature and allowing at least 4 hours to reconstitute; and the accuracy of measurement of the product is improved when performed by weight, not volume (scooping), as the clumpy texture of the product yields wide variability when volume measurement is attempted.
- GNC® Premium Puppy Milk Replacer (Lot#2170), a relatively new entrant to the powered milk replacer and captive store brand marketed by Petsmart, has remarkable similarities to PetAg's® Esbilac® in terms of labeling, Guaranteed Analysis, ingredient composition, use instructions, and overall performance testing in the lab (measurement, solubility, etc.).
Adherence to Guaranteed Analysis - Fox Valley®
Fox Valley® products demonstrate some consistent trends when compared to different lots of the same product manufactured over a multi-year period. As shown in the table below, independent lab tested protein values reveal a consistently high value as compared to the Guaranteed Analysis (GA) minimums. In some cases, the protein values of FV 20/50 and FV 25/30 have been significantly higher, as shown below. The higher protein may or may not create issues when used, depending on the species, age and condition of the animal and any sensitivities to excessive levels of protein in the formula. Values for fats appear to be more consistent, generally within +/- 5% of the GA. Values for ash only exceed GA maximum once. Moisture content (water) is generally acceptable, except for FV40/25 where the tested values consistently exceeded GA maximums and 40% or more higher with some lots. These instances can result in formulas that are less in overall solids relative to user expectations.
Macro and Micro Minerals - Fox Valley®
The table below shows the values for the macro and micro minerals in the Fox Valley® tested products, and illustrates changes in concentrations of those minerals in 2012 sampled lots and lots from prior years. The presence of various minerals decreased in the FV 20/50 and FV 32/40 products, again compared to prior years, and increased in FV 40/25 as shown in the table below. In some cases, these increases or decreases were significant in percentage change.
While the mineral values increased for FV 40/25, several of those values where significantly lower than for the other Fox Valley® products. This can be a potential issue if the only source of minerals is from one or more of these products, especially for very young animals in early formative stages of development. Lastly, as noted in previous testing, the remarkably low concentrations of dietary copper have continued to drop even further, which now appears to be a chronic problem for Fox Valley® product lines. Growing animals should be closely monitored for any ill effects associated with a diet severely deficient meeting minimum required levels of dietary copper. It is important to note that attempting to accurately and manually add any additional supplemental dietary copper or any other micro minerals in such extremely small amounts (parts per million) can result in inadvertently exceeding acceptable ranges and can result in unwanted mineral toxicity. More on this will be provided in the Update available in April, 2012.
Solubility Tests - All Products
The chart at right confirms earlier WildAgain solubility testing that illustrates almost all of the powdered milk replacers, regardless of manufacturer, consistently appear to more fully reconstitute when using hotter water (175°F rather than just hot tap water at 125°F) and when given at least 4 hours time to reconstitute rather than simply using the product as an instant mix ready for immediate use. Specific product test results for solubility are shown in the milk replacer product testing data sheets.
Of particular note is that the products with much higher relative fat content (those highlighted in the red shaded quadrant in the chart at right) show poor solubility when prepared as an instant mix intended for immediate use. This could easily result in gastrointestinal and growth problems if the animal is unable to digest utilize a formula that is not fully reconstituted and thus largely unavailable to the animal.
The KMR® milk replacer (Lot#HG0101K) tested (using 175F degree water) showed significant insolubility when mixed for immediate use as shown in the leftmost image at right, with noticeable clumps of unwetted powder visibly apparent in the graduated cylinder upon filling the cylinder for the solubility testing (the image below is the KMR® powder prior to mixing with water). As a result the mixed formula showed two distinct layers of separation, with the bottom layer consisting of very dilute formula. Feeding this formula to an animal will result in considerable underfeeding of the intended amount of nutrients expected of a fully reconstituted formula.
When this same product was reconstituted with water and allowed to rest for at least 4 hours prior to use, almost no separation of product was observed (rightmost image), suggesting an almost complete rehydration of the dry powder. As such, this formula should be much more available to and more fully utilized by the animal.
Physical Characteristics - Measurement Issues
The chart below shows the effects that the texture of the dry powdered product can have when measuring the product by volume, as opposed to weighing, when simply using the plastic scoop that is usually supplied with the product. For the Fox Valley® products, which consistently are of very fine consistency of uniform particles, measurement error is minimal when using a scoop for measuring. However, as shown below, measurement error is much more significant for KMR® and GNC® when using a scoop, because of the clumpy and non-uniform texture of the product (see image above), which creates opportunities for both voids and compaction when using a plastic scoop. (The green bars in the chart show the degree of variability from an average scoop to be expected about two-thirds of the time (calculated as 1 standard deviation), while the red bars indicate the maximum high and low % error during the lab tests. Shorter bars indicate less expected error.)
Fox Valley® Product Disclosures - Product Labeling vs. Manufacturer Website
The images below, taken from both Fox Valley's® website (left) and package labels (right) in early March, 2012, indicate discrepancies between what is disclosed for product ingredients for FV 32/40 and FV 40/25. It is unclear which version of the product ingredient list a user should rely upon. While certain sections of the manufacturer's website are incomplete and others appear to be dated, it may be a fair assumption that the actual label on the package may be more current and accurate. The FDA allows a six month "grace period" for manufacturers to change/update package labels to reflect changes in product formulation/ingredients.
GNC® Premium Puppy Milk Replacer - Remarkable Similarities to Esbilac®
The recent Midwest Labs component testing and lab testing, plus the images below from the GNC® can (left) and PetAg's website (right) for Esbilac®, suggest that this product, a captive store brand for Petsmart, may be manufactured by PetAg for resale through Petsmart's national retail distribution channels. Again, there is no direct evidence that this product is manufactured by PetAg, but the similarities are truly remarkable. To date, WildAgain has had no reports by rehabilitators who have used this product with wild mammals in rehabilitation.
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