What's New?
>> You may need to refresh your page to see the most recent updates.
WildAgain's Wildlife Formula Calculator was updated March 5, 2024. Please download the newly updated version and discard any prior versions. New video tutorials have been added.
March 2024
Fox Valley 40/25 Milk Replacer – testing and analysis. Fox Valley 40/25 is one of many substitute milk formulas produced by Fox Valley Nutrition and is available online from various retailers and the company. It is a cow-based 40/25 protein/fat formulation. This is an updated series of tests of a 2023 lot of this product that is widely used by wildlife rehabilitators. The Lab test data spreadsheet has been updated for this 2023 lot for proximate values and minerals. The Calculator now also includes this lot. Part 1 of this series presents independent lab test results of the product as well as WildAgain’s performance testing on handling and measurement. Part 2 (PDF) presents some key takeaways of the product from these test results that rehabilitators may want to consider when deciding about using this product as a formula base or blending ingredient.
February 2024
WildAgain's Wildlife Formula Calculator was updated on February 22. First, updates to 4 products with lots made in 2023, including Esbilac, GME, Fox Valley 32/40 and Fox Valley 25/30, have been added. The products were tested by an independent lab and are now available in the Calculator drop-down menu. For lot-specific data (proximate analysis and dietary mineral content), the Lab Test Data Spreadsheet has also been updated with these tests.
​
Second, the Cottontail 'Average' species milk selection has been updated to include more complete species milk research data. A more complete discussion of this update and the research study it is based on is posted on Quick Reads and available here as a PDF.
Remember, while the Calculator can help with the math to compare the formula recipe to the species milks, other factors contribute to formula’s effectiveness, digestibility, etc. – such as storage, preparation, microbiome. Some of this information is already in the Quick Reads – and more being developed.
​
​
Rancidity Testing in Milk Replacers - Early 2024 Update. Ten rancidity tests were performed on 6 different products. Consistent with testing last year, GME and KMR continue to show elevated peroxide value (PV) levels indicating the onset and progression of rancidity. For the test results of the other products and more analysis of these recent samples, click here (PDF).
January/February 2024
Training Videos on the Wildlife Formula Calculator A set of a dozen short videos have been posted. They provide an overview of the Calculator; how to use the drop-down menus; adding custom input for your species or formula recipe products/ingredients; how to use the Measurement Guide that converts parts to gram weights; the kcal calculator; the Cost Estimator and more.
November 2023
Milk Powders for Human Babies and Other Mammals Reconstitute Differently. (PDF) People familiar with preparing powdered infant milk formula (IF) for human babies often expect other milk powders to mix the same – quickly and easily. However, casein-rich milk replacers used by rehabilitators are more difficult. This short article identifies and explains the obstacles of casein protein reconstitution. It also provides links to other resources that provide some easy steps used in formula preparation to overcome these hurdles. Following these steps results in a more completely reconstituted, nutritious and digestible substitute wildlife milk formula.
August 2023
Health impacts from long distance wildfire smoke and implications for rehab. (PDF) Wildfire smoke has affected large areas and millions of people during 2023, in some cases thousands of miles from the location of the wildfires. This short article explains emerging research on ways some of these harmful micro-particulates may affect wildlife, resulting in significant respiratory and cardio-vascular conditions and affect populations. It also identifies some of the action steps rehabilitators may consider when admitting wildlife in respiratory distress. The short resource list will be expanded as new research emerges.
Tips to Prevent Aspiration in Juvenile Squirrels. (PDF) Juvenile squirrels in rehab may show respiratory conditions after being fed by a well-intentioned rescuer. Respiratory conditions may also develop in a rehab facility - especially when newer people are feeding the young squirrels and during a very busy season. This brief article offers some reminders to help prevent and reduce respiratory conditions resulting from feedings by both new and experienced volunteers and rehabilitators.
June 2023
Rancidity concerns continue with KMR as recent samples are still testing at elevated Peroxide Value (PV) levels. The new formulation of KMR® continues to demonstrate concerning shelf-stability issues with five recent samples testing at PV's from 55-86 levels at 18 months since manufacture, well above established guidelines for edible oils. This continues the trend of increasing and elevated PV levels from three 2021 samples from the prior formulation tested at less than 18 months old. Click here for more information. [Additional samples are being collected and submitted for analysis.]
May 2023
Two new videos on powdered milk reconstitution. The first explains the importance and many reasons why incomplete reconstitution of milk powder can create difficulties for both animals and caregivers. It's much more than a quick mix and stir. The second video provides a hands-on, step-by-step walk-through of the improved reconstitution method that results in a smoother, clump-free formula better for feeding young mammals in rehab. Go to the bottom of any page in the website and click the Mixing Guide button.
March 2023
Wildlife Formula Calculator has Expanded Measurement Guide - new Part B divides total water between multiple powders. When a recipe calls for using multiple milk replacer powders, each powder should reconstitute separately. This new feature calculates, from the total amount of water in the recipe, how much water (in grams) should be used to separately mix with each powder to more fully reconstitute.
New Quick-Read - Highlights of New Milk Replacer Resources on Ewildagain.org. With the arrival of spring, wild mammal orphans and injury cases are being admitted throughout North America. This also means increased discussion on substitute milk replacement. There is more discussion than usual this year since some milk replacer powders have changed (new formulations) and ‘new’ powders are on the market. Rehabilitators are wondering about those changes and how they may impact the young mammals in their care, as well as consideration of some of the newer products now available. This short summary (2-page PDF) provides some brief discussion and resources addressing those topics and concerns. It includes milk powder changes described by product; ways in which reconstitution and mixing methods matter and can be improved; elevated peroxide values in 2 milk powders (e.g., rancidity tests); updates to the WildAgain formula calculator; and an updated formula Mixing Guide (see below). More resources will be available soon, including articles and new online videos.
Wildlife Milk Formula Mixing Guide updated and expanded. The Mixing Guide has been updated with a few additional steps and suggestions. Additionally, a new 'Quick Guide' is provided as a quick reference that summarizes the key steps involved when preparing formula. Click here for the Guides.
February 2023
Zoologic® 42/25 Milk Replacer – testing and analysis. This product is from PetAg® that "...may be used alone or blended with other products in the Matrix family to formulate a milk replacer with nutrient levels that closely match a species' natural milk." This is an updated series of tests of this product that is commonly used by wildlife rehabilitators. It also provides comparisons to KMR®. Part 1 of this series will present independent lab test results of the product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) will present some key takeaways of the product from these test results that rehabilitators may want to consider when deciding about using this product as a formula base or blending ingredient.
Zoologic® 33/40 Milk Replacer – testing and analysis. This product is from PetAg® that "...may be used alone or blended with other products in the Matrix family to formulate a milk replacer with nutrient levels that closely match a species' natural milk." This is an updated series of tests of this product that is commonly used by wildlife rehabilitators. It also provides comparisons to Esbilac®. Part 1 of this series will present independent lab test results of the product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) will present some key takeaways of the product from these test results that rehabilitators may want to consider when deciding about using this product as a formula base or blending ingredient.
January 2023
New Wildagain Wildlife Formula Calculator 'Cost Estimator' and other enhancements have been added. As rehabilitators consider blended formula recipes to match mom's milk by using one or milk replacers and other supplements, what's the actual cost of a cup of prepared formula? The Cost Estimator uses default retail product prices, or user supplied products and prices, to provide an estimated cost per cc, cup, or pint. Beta testers of this feature have commented "...easy to use...informative...revealing." Other enhancements include now providing user input of up to 9 individual species milk study values beyond the Calculator supplied options. Lastly, the Measurement Guide will accept formula recipes constructing using either (1) parts of ingredients, and now, or (2) weights of ingredients. This facilitates measuring by weight rather than by volume (scooping) which eliminates the measurement error characteristic of fluffy and sticky spray dried milk powders.
Fox Valley 32/40 Milk Replacer – testing and analysis. Fox Valley 32/40 is one of many substitute milk formulas produced by Fox Valley Nutrition and is available online from various retailers and the company. It is a cow-based 32/40 formulation. This is an updated series of tests of this product that is widely used by wildlife rehabilitators. Part 1 of this series presents independent lab test results of the product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) presents some key takeaways of the product from these test results that rehabilitators may want to consider when deciding about using this product as a formula base or blending ingredient.
MannaPro® Kid Goat Milk Replacer – testing and analysis. This Kid Goat milk replacer is one of many substitute milk formulas produced by MannaPro for domestic livestock and pets. It is available online from various retailers. It is a cow-based 23/26 formulation with whey as the primary protein source. Part 1 of this series presents independent lab test results of the product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) presents some key takeaways of the product from these test results that rehabilitators may want to consider when deciding about using this product as a formula base or blending ingredient.
December 2022
Tailspring Milk Replacers – testing and analysis. Meyenberg, founded in 1934 producing goat milk products for human consumption, 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). Part 1 of this series presents independent lab test results of the product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) presents some key takeaways of the product from these test results that rehabilitators may want to consider when deciding about using this product as a formula base or blending ingredient.
Wombaroo Squirrel Milk Replacer – testing and analysis. Wombaroo Squirrel Milk Replacer is one of many specialized substitute milk formulas produced by Wombarro Food Products located in South Australia, Australia, and available online in North America. It is a cow-based 34/45 formulation and uses human grade ingredients. Part 1 of this series presents independent lab test results of the product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) presents some key takeaways of the product from these test results that rehabilitators may want to consider when deciding about using this product as a formula base or blending ingredient.
Wombaroo Rabbit Milk Replacer – testing and analysis. Wombaroo Rabbit Milk Replacer is one of many specialized substitute milk formulas produced by Wombarro Food Products located in South Australia, Australia, and available online in North America. It is a cow-based 37/42 formulation; contains added Capric and Caprylic fatty acids; and uses human grade ingredients. Part 1 of this series presents independent lab test results of the product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) presents some key takeaways of the product from these test results that rehabilitators may want to consider when deciding about using this product as a formula base or blending ingredient.
November 2022
New Goat's Milk KMR® 2022 – testing and analysis. PetAg® announced a new kitten milk replacer powders on their website (www.petag.com) during 2022. Users of KMR® now have an alternative based on goat's milk. The obvious difference between the two 40/28 formulations is goat milk based versus cow milk based. Yet test results indicate other key differences that should be considered prior to use.
Part 1 of this series presents independent lab test results of the new product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) presents some key takeaways and comparisons between the two KMR® formulations from these test results that rehabilitators may want to consider when deciding about using this new product as a formula base or blending ingredient.
New KMR® 2022 – testing and analysis. PetAg® announced changes in several of their primary milk replacer powders on their website (www.petag.com) in early 2022, including a newly reformulated KMR®. This is not necessarily a cause for immediate concern as manufacturers regularly make product changes from time to time and for many reasons.
Part 1 of this series presents independent lab test results of the new product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) presents and discusses 8 key takeaways from these test results that rehabilitators may want to consider when deciding about transitioning to this new formulation of a widely used milk replacer.
October 2022
New Esbilac® 2022 – testing and analysis. PetAg® announced changes in several of their primary milk replacer powders on their website (www.petag.com) in early 2022, including a newly reformulated Esbilac®. This is not necessarily a cause for immediate concern as manufacturers regularly make product changes from time to time and for many reasons.
Part 1 of this series presents independent lab test results of the new product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) presents and discusses 7 key takeaways from these test results that rehabilitators may want to consider when deciding about transitioning to this new formulation of a widely used milk replacer.
New GME® 2022 – testing and analysis. PetAg® announced changes in several of their primary milk replacer powders on their website (www.petag.com) in early 2022, including a newly reformulated GME®. This is not necessarily a cause for immediate concern as manufacturers regularly make product changes from time to time and for many reasons.
Part 1 of this series presents independent lab test results of the new product as well as WildAgain’s performance testing on measurement and reconstitution. Part 2 (PDF) presents and discusses 8 key takeaways from these test results that rehabilitators may want to consider when deciding about transitioning to this new formulation of a widely used milk replacer.
Post (Busy) Season Review: Celebrating Success & Seeking Improvement. Towards the end of the calendar year, many wildlife rehabilitators ‘wind down’ from their ‘busiest’ rehab seasons and finalize their rehab records. It is also a time, when not fully immersed in daily operations, to go beyond the annual reports to reflect on successes and challenges and, as importantly, identify changes for the next year. This article offers some tips from ‘post season’ reviews conducted by businesses and rehabilitators to help celebrate successes and plan the future year. (Click here for the PDF)
September 2022
KMR testing (four 2021 lots) - Increased unsaturated fat and rancidity issues. WildAgain had extensive lab tests conducted on KMR milk replacer powder manufactured in 2021 as a baseline to compare to the new KMR being manufactured in 2022 once it becomes available. While the tests indicated the overall nutrient composition remained similar from 2018, they suggest the formulation of the fatty acids had changed – potentially resulting in greater susceptibility to rancidity, especially if exposed to heat and oxygen. The peroxide value tests on those KMR 2021 lots did reveal slightly elevated rancidity – meaning rehabilitators will want to consider extra care when storing and using the milk powders. Full analysis here (PDF).
August 2022
Esbilac has been reformulated - is it still an instant mix? PetAg has reformulated some of their milk replacer powders in 2022, with new labels and ingredient changes. Test results recently completed of the proximate analysis on Esbilac made in early 2022 have been posted in WildAgain's Wildlife Formula Calculator and the more detailed lab test data spread sheet. A summary of the reconstitution testing is available here. It confirms improved performance of allowing the prepared formula to rest in the refrigerator for a minimum of 8 hours after mixing. This results in a more complete reconstitution of the powdered Esbilac to liquid form and allows for more complete digestion – at least for young wild mammals. Further analysis of Esbilac, KMR and GME will be posted in the coming months.
June 2022
Wildlife Rehabilitators Provide More Benefits Than People Realize. Rehabilitation of individual wild animals is a major objective and certainly valuable, especially for animals receiving care. Wildlife rehabilitators provide many other services that benefit wildlife and people beyond direct animal care. This article provides some examples (PDF).
May 2022
WildAgain's Wildlife Formula Calculator was updated May 29 with 7 product/lots that have been tested in spring 2022. Recent lots for those products were tested by an independent lab and are now available in the calculator. Included are milk replacer powders made by PetAg, Fox Valley, Wombaroo and MannaPro. These are lots manufactured in 2021 which are still in use by many rehabilitators.
For lot-specific data (proximate analysis and dietary mineral content), the Lab Test Data Spreadsheet has also been updated with these tests. The User Input tab has examples that may be included in formula recipes for those considering them, such as a medium chain triglyceride (MCT) product.
Remember, while the calculator can help with the math to compare the formula recipe to the species milks, other factors contribute to formula’s effectiveness, digestibility, etc. – such as storage, preparation, microbiome. Some of this information is already in the Quick Reads – and more being developed.
July 2021
Milk Replacer Update: Trends and Analysis - Summer 2021. Trends are identified in the context of 18 years of test results for many products. This extended analysis examines and discusses the lab test results of 30 product/lots performed year to date. While continuing to identify variances from the Guaranteed Analysis, the update introduces the metric of "Expected Values" for total solids, protein and fat as a more reliable predictor of nutritional content in the products. The summary provides overall observations, takeaway thoughts, and action steps for incorporating the products to create wildlife substitute milk formulas. Described as "comprehensive and revealing" by one of our reviewers/editors, this newly added content may help to address some of the reported issues and problems seen this year. (Just want the highlights? Click here.)
NEWLY EXPANDED - Storage time and temperature can affect reconstitution for milk replacers. Previously posted in March 2021, this article takes a much deeper dive into the affects of improperly storing powdered milk replacer. Research and testing suggest it is much more than 'store in a cool, dry place and use before the expiration date.' Learn how product freshness, storage temperatures and how soon it is used make a big difference for the animals. An easy storage checklist is also provided.
September 2021
Recent Lab Test Results for Esbilac. Three recent tests are summarized below and will be added to the Wildlife Formula Calculator and Lab Test Data Spreadsheet very shortly:
Lot# Date made Protein% Fat% Calcium% Phosphorus% Ca:P ratio
​
3510E Dec 2020 36.6 36.2 1.36 0.90 1.51
0421E Feb 2021 36.7 39.9 1.33 0.92 1.44
0751E Mar 2021 36.2 40.5 1.11 0.78 1.42
​
1919/20 ave. (16 lots) 35.8 37.8 1.11 0.82 1.36
​
Summary observations: Protein levels increasing very slightly; fat levels increasing towards minimum guarantee of 40%; Calcium increasing about 20% from prior years; Phosphorus up about 10% from prior years; Ca:P ratio up slightly due to higher calcium concentrations.
​
June 2021
WildAgain's Wildlife Formula Calculator was updated June 15 with thirty new product/lots that have been tested so far this year. Recent lots for various products have been tested by an independent lab and are now available in the calculator. These are primarily those lots manufactured in 2020 which are still in use by many rehabilitators, but also includes a few 2021 lots. For lot-specific data (proximate analysis and dietary mineral content), the Lab Test Data Spreadsheet has also been updated with these 30 tests. Additionally, new species milk data has been added to the drop-down menu in Step 1 of the calculator.
May 2021
Dry matter vs. wet matter update. Several recent social media posts continue to indicate lack of fundamental understanding between wet and dry matter, when comparing milk replacer products. Unfortunately some of the posts are incomplete, incorrect and misleading and may result in the reader pusuing a wrong course of action. For example, is there more protein in Esbilac powder or prepared Esbilac liquid sold in a can? Does Fox Valley 32/40 or GME have more kcals per gram? These simple questions are answered along with the math that allows anyone to make valid and accurate comparisons.
Rodent chow product update. An analysis of chow products first published in 2003 has now been updated and expanded to 39 available products. It addresses many common questions including: Should I use rodent chow, or not? Which products are designed for growing animals? Which products have the most fat? What are the ingredients? What about protein content, and calcium and phosphorus? How should I properly store them? And much more.
April 2021
Preparing formula. Recent research on milk replacer powders shows that preparation factors can substantially impact the formulas as well as wild animals’ health and growth. Minor adjustments with preparing formulas can help. Example of modified preparation instructions.
Compilation of squirrel rehab resources on EwildAgain.org. In response to rehabilitator requests, this resource list of items and links will hopefully make it faster and easier to find a particular subject related to squirrel rehab (e.g., aspiration, stool problems, rodent chow and squirrel natural history). Some of papers were previously available only in WildAgain's Squirrel Rehabilitation Handbook (3 ed.).
Lab test results – View the lab test spreadsheet for more complete independent lab test data on nutrition components, dietary minerals and kcal for the product/lots listed below.
Zoologic 42/25 Lot# 1149-ZF-1369. Guarantee vs. lab test: Protein >42.0% vs. 43.1%. Fat >25.0% vs. 26.6%. Calcium 1.28%, Phosphorus .97%.
March 2021
Formula and feeding section – new and expanded. New format has more features and updated resources. Learn more on species milks, functions of milk components (e.g., proteins, fats, carbs) and why important for rehabilitators to consider. The expanded Wildlife Formula Calculator allows easy comparison of formula recipes to the species milks and weights. It shows that preparation method makes a significant difference as to the extent the young animal can benefit from the formula, with including photos and charts reasons for mixing steps. Results of lab tests are provided on 140 milk powders for rehabilitators wondering about how specific milk replacers compare between products and over time. The resources support rehabilitators having key information to make informed decisions about formula recipes, product selection, storage and mixing – which can help the animals in their care. More articles, including ‘quick reads’ and resources are regularly added. Online and virtual training will be available on these and more topics by mid-2021.
Reconstitution of powdered milk products. Discusses critical differences between dissolving milk powders in water versus reconstituting (using modified mixing and resting methods). Proper reconstitution can improve dispersal/dissolution of the powder into more digestible formula by 90%. See explanations and photos of test results for various products, including Fox Valley, Esbilac, and Zoologic powders. Conclusions suggest new methods involving water temp, powder/water mixing sequence, and resting time post-mix.
Lab test results – View the lab test spreadsheet for more complete independent lab test data on nutrition components, dietary minerals and kcal for the product/lots listed below.
Fox Valley 32/40 Lot# 012350. Guarantee vs. lab test: Protein >32.0% vs. 36.8%. Fat >40.0% vs. 38.2%. Calcium 1.54%, Phosphorus .96%. (Dietary copper not detected.)
​
Fox Valley 32/40 Lot# 013050. Guarantee vs. lab test: Protein >32.0% vs. 36.0%. Fat >40.0% vs. 41.3%. Calcium 1.64%, Phosphorus .93%.
​
Fox Valley 25/30 Lot# 052550. Guarantee vs. lab test: Protein >25.0% vs. 29.3%. Fat >30.0% vs. 30.5%. Calcium 1.58%, Phosphorus 1.08%. (Dietary copper not detected.)
​
Fox Valley 40/25 Lot# 023200. Guarantee vs. lab test: Protein >40.0% vs. 42.4%. Fat >25.0% vs. 24.2%. Calcium 1.76%, Phosphorus 1.01%. (Dietary copper not detected.)
​
Esbilac 33/40 Lot# 1640E-1890. Guarantee vs. lab test: Protein >33.0% vs. 36.1%. Fat >40.0% vs. 39.3%. Calcium 1.12%, Phosphorus .80%.
Esbilac 33/40 Lot# 0080E-0340. Guarantee vs. lab test: Protein >33.0% vs. 36.6%. Fat >40.0% vs. 39.3%. Calcium 1.09%, Phosphorus .86%.
Zoologic 33/40 Lot# 3350ZE3630. Guarantee vs. lab test: Protein >33.0% vs. 34.8%. Fat >40.0% vs. 41.8%. Calcium 1.23%, Phosphorus .69%.
​
Updated COVID-19 guidance for rehabilitators. This PDF (right) provides new suggestions for rehabilitators and others working with animals as to transmission mitigation strategies and health protection measures. (**Also check with your state for any recent changes in rehab regulations and/or temporary species-specific suspensions.)
February 2021
Reconstitution of powdered milk products (click here for the new section). Discusses critical differences between dissolving milk powders in water versus reconstituting (using modified mixing and resting methods). Proper reconstitution can improve dispersal/dissolution of the powder into more digestible formula by 90%. See explanations and photos of test results for various products, including Fox Valley, Esbilac, and Zoologic powders. Conclusions suggest new methods involving water temp, powder/water mixing sequence, and resting time post-mix.
Helping wildlife and reducing work. Rehabilitators help wildlife beyond direct care. As rehab busy season approaches, good time to remember and expand ways to help animals that may help rehabilitators reduce their workload and costs. See the longer discussion here.
January 2021
Estimating formula feedings per day. Grappling with calculating kcals to help figure number of formula feedings per day? Review of factors influencing the kcals and decisions, with a short article and chart with weights as well as a longer paper (PDF) with more science and equations.
This PDF is the companion piece that provides a longer and more in-depth foundation of the science and equations used in estimating minimum kcal requirements per day.
December 2020
Uses of annual rehab reports beyond agency requirements. Consider using these annual records to help planning, fundraising, training and more.
​
Comparing annual rehab records over several years can help planning (e.g., identifying when wild babies arrive, length of stay in rehab, replenishing supplies inventory), as well as identifying other trends that can affect rehab decisions and practice.
