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Tailspring Puppy and Kitten Milk Replacers -
Part 1. Lab and performance testing

Meyenberg was founded in 1934 as a producer of goat milk products for human consumption. They recently introduced a line of pet milk replacers in early 2021 under a new Tailspring brand, including for Puppies (33/40) and Kittens (42/25). These products are made from Human-Grade A Whole Goat Milk. By incorporating whole goat milk as the primary ingredient, few additives are required and no preservatives are included. This article (Part 1) presents the results of the independent lab assays and WildAgain's performance tests. Part 2 discusses and offers suggestions on for wildlife rehabilitators considering the use of these products (PDF).


When compared to cow's milk, goat milk provides several benefits that contribute to enhancing digestion and digestive health. As such, it is often marketed and suggested for digestive sensitivities; for very young, developing GI systems; and animals in stressful environments. The following is a listing of some of the characteristics that beneficially differentiate goat milk from cow's milk:

Enhancing digestion

- Smaller sized fat globules (with higher homogeneity and greater surface area).
- Better fat utilization due to twice as many medium chain fatty acids (MCFA).
- Favorable 𝛼s1-casein : 𝛼s2-casein ratio (less gastrointestinal allergenic inflammation).

- Lower concentration of lactose.
- Higher overall dietary mineral levels with higher bioavailability.

Enhancing digestive health

- Contains 250-300 mg/l oligosaccharides (4-5x than in cow’s milk) - reduces intestinal inflammation; aids in recovery from colitis; protects intestinal flora against pathogens (such as Escherichia Coli).

- Higher conjugated linoleic acids (CLA’s) for immune stimulation and growth promotion. 
- MCFA have been shown to possess antimicrobial properties. 

This list of benefits seems to make consideration of goat milk based milk replacers an attractive option for wildlife rehabilitators.

Part 1. This analysis provides the chemical analysis of the two products and some of their primary formula preparation performance characteristics such as measurement and reconstitution. It does not assess how the new product will perform when fed to orphaned wildlife in rehabilitation, though some of the information certainly can be used with decisions and use. 

Part 2. An accompanying article discusses some of the key metrics for the two products and offers some suggestions that wildlife rehabilitators may consider when deciding if one or both of them might be suitable for use in substitute milk formula recipes for feeding to young wild mammals.

The following list highlights some of the key findings prior to a more detailed presentation of test results and analysis. 

√ Ingredients. The ingredient list is exactly the same for each product, though a few are listed in a slightly different order reflecting different concentrations between the two formulations.

√ Proximate analysis. The protein/fat amounts mirror what has been commonly used by other milk replacer manufacturers, especially those produced by PetAg®. Wirth the exception of moisture content, both products adhere fairly closely to the Guaranteed Analysis (GA) as disclosed on the product label. Moisture is notably above the (GA) of no more than 5%.

√ Ash. As for dietary minerals, overall ash content is in the 5-7% range which is comparable to other milk replacers. Of slight concern is the calcium concentration at only .77% in the Puppy product. Ideally, calcium is generally found to be around 1.0% or more.

√ Fatty Acids. The profile for the Kitten product is shown below, but the Puppy product is still in testing.

√ Rancidity. Shelf-stability does not appear to be an issue with with product, with peroxide values well below established guidelines for edible oils. This is even the case for the samples that were tested that were 80+% into their quoted shelf life ('best by' date). Even so, proper storage is remains critical to preserve freshness and prevent the onset of rancidity.


√ Physical characteristics. Powder is loose, fluffy and sticky, not unlike the other spray-dried milk replacers. Measuring powder by volume or parts rather than weighing caused error rates of +4% to -6% from the calculated average weight when tested. 


[Note on the following discussion on reconstitution performance: The images of the products during wetting, sinking and whisking below would suggest very poor final reconstitution performance (dispersal and dissolution). NOT SO !! The combination of adequate whisking and the resting period produced some Best-in-Class reconstitution performance results. This once again demonstrates that these products, as with other milk replacers, do not demonstrate 'instant mix' properties.]

√ Reconstitution (wetting and sinking). Poor performance when correctly adding powder to warm water, with test samples only appearing to be 5-10% submerged in <5 minutes. 

√ Reconstitution (dispersal and dissolution). Due to poor wetting performance, mechanical whisking was required to begin the powder dispersal process. The Puppy product required a 5 minute whisk to the point of no visible dry powder or clumps. The Kitten product required a full 7 minutes to get to the same point. The Puppy product demonstrated exceptional dispersal and reconstitution properties as an instant mix and with an 8-hour rest. For the Kitten product,  an 8-hour resting period from preparation (mixing) to final use (feeding) demonstrated outstanding final reconstitution with an improvement of 91%. Without the rest period and quickly prepared for an instant use/feeding, over 6% of the Kitten powder remained dry and not fully reconstituted.

Ingredients (as listed on the package label)


The following table lists a side-by-side comparison of the ingredients of the Tailspring Puppy and Kitten milk replacers. The list of Primary Ingredients indicates the products are comprised mostly of goat's whole milk and protein with some added safflower oil to boost fat levels. 

The list of Secondary Ingredients is relatively short compared to other milk replacers that do not use whole milk (either goat or cow) as the base ingredient. Sunflower lecithin is added likely for its properties as a natural fat emulsifier that can help to reduce the "stickiness' of milk and deter fats from clumping together. Gum arabic is presumably intended for prebiotic benefits that are essential for digestion, development, and the immune system. (Gum arabic is a complex mixture of glycoproteins and polysaccharides and is soluble in water.)

No fermentation products are added to these formulations.

Tailspring list of ingredients.jpg

Proximate analysis

The following table shows the results of the proximate analysis performed by the lab as compared to the Guaranteed Analysis (GA) (max/mins). The red shaded values indicate where the lab analysis determined that the component concentrations failed to adhere to the maximum or minimum guarantees. 

Notable is that moisture exceeds the maximum guarantee of 5% by a significant amount. Proteins and fats in the Puppy product are slightly lower than the GA whereas the Kitten product exceed the minimums. The metabolizable energy content (ME Kcals) equals 5.33 per gram of dry powder for the Puppy product with the higher fat content, while the Kitten product equals 4.72 kcals per gram of dry powder. These proximate values are included in the drop down menus found in the  Wildlife Formula Calculator

Tailspring proximate analysis.jpg

Ash - dietary minerals

The following table shows the results of the dietary mineral analysis performed by the lab. Of some concern is the relatively lower concentration of Calcium in the Puppy product. The Phosphorus levels appear to be in normally accepted ranges. The Ca:P ratio is over 1.00 in both products. 


As for the other minerals, most other concentrations appear to be in normally expected concentrations for goat-milk based replacer, with the exception of Manganese which is very low/non-detectable. 

Tailspring dietary minerals.jpg

Fatty acid profile

The fatty acid profiles for the Tailspring Milk Replacers are shown below. Both have about the same concentrations of Caprylic and Capric acids. The Puppy product has about twice the concentration of monounsaturated fat, with twice as much oleic acid as the Kitten product.

Tailspring Fatty Acid Profile.jpg

Peroxide Value (PV) test results

Both products show very good shelf-stability with Peroxide Value test results (PV) well below the acceptable level of PV10 for edible oils and fats. This indicates very little trace of the onset of rancidity after 18 months post manufacturing. 

[As always, the sniff test was performed to assess possible rancidity prior to the actual PV performed by the lab. The products did have a strong odor but it was not due to rancidity and not deemed to be an issue. The reason for the distinctive 'goaty' smell is discussed further in Part 2. 

Tailspring PV Values.jpg

Physical characteristics and measurement error [tests performed by WildAgain]

The Tailspring milk replacers have the characteristic loose and fluffy consistency common to other spray dried powdered milk replacers as shown in the following images. The Puppy product has more defined clumps likely due to the higher fat content of the formulation. This physical property always provides challenges when measuring a given amount of powder to include in a formula recipe. Mixing by parts using the provided scoop or some other volume measure results in measurement error ranging from +4% to -6% as shown in the chart below. Weighing the powder eliminates this unnecessary user induced error, provides for a uniform formula at each mixing and preparation (Mixing Guide), and helps insure consistent nutrition in the formula.​

Tailspring Puppy Kitten Powder Compare.jpg
Tailspring weights.jpg

Reconstitution tests - wetting and sinking [tests performed by WildAgain]

Samples of both products (15 grams of powder each) were added to 110°F warm water (60 grams each) and allowed to wet for 5 minutes. Views from the top and side (shown below) indicate the Puppy product did wet and sink better than the Kitten product, however both fail the test of being an instantized dry powdered milk product. Much of the Puppy product that did sink remained agglomerated and clumpy right at or near the powder-water interface. The Kitten product showed very little sinking and dissolution (≈5%), with most of the powder floating on the water still in dry form.

Tailspring Powder on Top Compare.jpg
Tailspring Sinking compare.jpg

Reconstitution tests - dispersal and dissolution [tests performed by WildAgain]

Both samples were whisked for 5 minutes to the point of no visible dry powder or clumps being present and detectable. The Kitten product required an additional 2 minutes to achieve this state (7 minutes total). Images of both products (they appeared exactly the same) after whisking are shown below and appear smooth, milky and clump-free at this point.

Tailspring after whisking.jpg

Reconstitution tests - dispersal [tests performed by WildAgain]

The samples of the liquid formula were then poured through the stack of sieves, with the largest mesh size on top (500µm). The images that follow show the unwetted powder retained (trapped) by the 500µm sieve, even though visually it had appeared that the formula just prepared had been completely mixed and free of any dry powder clumps. The image on the left is the Puppy formula that was mixed and not allowed to rest, simulating an instant mix use/feed as directed on the product label instructions. Very respectable performance. The image on the right shows the Kitten product had very poorly wetted even after a full 7 minutes of whisking until the liquid appeared clump-free. 

Tailspring Initial Pour Compare.jpg

Reconstitution tests - a closer look at the Tailspring Kitten reconstitution steps [tests performed by WildAgain]

Given the surprising result for the Kitten product shown at right above, the following set of images provides a closer look into the tests performed on that product. After 5 minutes of poor wetting and sinking discussed above, the powder was forced into the water with a whisk and given 5 minutes of stirring. The powder was extremely sticky and clumpy, adhering to the whisk (metal loops and inside the loops) and the sides of the glass beaker. This required repeated scraping of the powder from the whisk and beaker side walls. The powder only began to appear wetted after 4 minutes, and then required an additional 3 minutes. It became clear upon pouring the formula on the 500µm sieve that as significant amount of powder had remained dry and was retained by the top sieve.

Tailspring Kitten Whisking.jpg
Tailspring Kitten after whisk and pour.jpg

The two images that follow show a remarkable difference in the amount of unwetted powder in the instant mix sample (left) versus the sample that was mixed and allowed to rest for 8 hours (right). This confirms prior observations for all of the other milk replacer products tested that showed  significant improvement (in terms of less unwanted, dry powder) after allowing the formula to simply rest a full 8 hours

Tailspring Kitten Instant to Rest Compare.jpg

Reconstitution tests - Efficiency

The following chart shows the added efficiency and improvement of the reconstitution of the powder into liquid form given the 8-hour resting period. The Kitten product showed a 90+% improvement. Surprisingly, the Puppy product showed amazing results as an instant mix versus the rest period. However, it should be noted that the sieves only measure down to 125µm in size, whereas milk particles range in size from 1 - 100µm. It is probably reasonable to presume that those particles that pass thru the bottom sieve (125µm) will likely achieve a more complete state of reconstitution given the longer resting time.

Following the chart are the images of the actual sieves used in performing the reconstitution tests. With the exception of the Kitten/Instant mix sample at 500µm, all of the other sieves are exceptionally clear, when compared to all other milk replacers tested by WIldAgain and included on this website.

Tailspring Recon Efficiency Chart.jpg

Tailspring Puppy Milk Replacer. 

Tailspring Puppy 500 sieve.jpg
Tailspring Puppy 250 sieve.jpg
Tailspring Puppy 125 sieve.jpg

Tailspring Kitten Milk Replacer. 

Tailspring Kitten 500 sieve.jpg
Tailspring Kitten 250 sieve.jpg
Tailspring Kitten 125 sieve.jpg

"What's it all mean?"


See Part 2 for analysis and discussion for rehabilitators that may be considering using Tailspring Milk Replacers as an ingredient in substitute wildlife milk formulas - either as a primary base product or in blending with other products/ingredients to achieve a close match to the mother's milk.





Tailspring products are manufactured and sold as a nutritional food supplement for puppies/dogs and kittens/cats. As such, wildlife rehabilitation would be considered an off-label use.

Product assays performed by the independent lab adhere to the Official Methods of Analysis of AOAC INTERNATIONAL (Association of Official Analytical Chemists) and the Official Methods and Recommended Practices of the AOCS (American Oil Chemists Society).

The authors have no conflicts of interest with the independent lab, or any of the products or manufacturers discussed in this article.

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