Freeze-Dried Rabbit Lung

Every rabbit slaughtered for meat yields a pair of lungs, a by-product USDA does not deem edible for people. Freeze-drying turns that wet, perishable organ into a light, shelf-stable piece without cooking it.^1,2,3

1. 01 // Source Rabbit lungs Lungs come off the carcass at slaughter as a meat by-product, the class AAFCO says covers lungs, spleen and kidneys.
2. 02 // Process Frozen hard The tissue is frozen fast, at about minus 30 to minus 50 degrees Fahrenheit, before any water is removed.
3. 03 // Process Vacuum dried Under vacuum the ice turns straight to vapor and is pumped away. There is no heat step, so bacteria survive.
4. 04 // Process Final drying A second stage strips leftover moisture, leaving a water activity of about 0.08 to 0.33.
5. 05 // Output Dried lung pieces Light, crunchy pieces; one maker turns about 1 pound of fresh lung into a 3 ounce bag.

1. 01

   Protein with the water out

   Fresh lung is mostly water. Freeze-dried, the same tissue guarantees at least 70% protein as sold, so a small weight adds real rabbit protein.³

2. 02

   Protein left uncooked

   In rooster assays, freeze-dried raw lung and other raw meals digested at 93.6 to 96.7% for essential amino acids, against 84.0 to 87.7% for rendered meals.⁴

3. 03

   Keeps the recipe on rabbit

   Lung adds organ protein without bringing in beef or chicken, two of the most reported triggers in a review of 297 dogs with proven food reactions.⁷

4. 04

   Uses the whole carcass

   Lungs are a slaughter by-product USDA does not deem edible for people. AAFCO notes such parts are safe and nutritious for animals, so pet food gives them a use.¹

How much No source publishes how much lung a recipe holds, and no dog trial has fed it; its protein data come from chick and rooster assays.⁴

1. Brands say

   Freeze-dried lung is high in protein

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   Arithmetic backs it: one label guarantees at least 70% protein as sold, after a pound of fresh lung dries to about 3 ounces. The catch is quality, since lung protein runs short on sulfur amino acids.^3,5

2. Brands say

   Rabbit lung is rich in iron

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   In a 5-rabbit study, lung held 5.79 mg heme iron per 100 g fresh, 91% of its iron, against 0.83 mg total iron in the meat. In a complete food the mineral premix, not the lung, sets the iron level.⁶

3. Owners say

   Rabbit is safe for dogs with food allergies

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   Rabbit appears only as single-dog cases in a review of 297 allergic dogs. Rarely reported is not the same as safe, and 24 of 31 novel-protein diets tested carried meats not on the label.^7,8

4. Brands say

   A very lean, very low-fat organ meat

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   No lab analysis of rabbit lung fat turned up. One label's minimums, 70% protein and 16% fat as sold, work out to about 4 parts protein per part fat: fairly lean, but not very low-fat, and a minimum is not a measured level.³

5. Owners say

   Freeze-drying makes raw lung safe to handle

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   Freeze-drying has no heat step, so bacteria that are present survive and can grow again once moisture returns. FDA testing of raw pet foods found Salmonella in 15 of 196 samples and Listeria in 32.^2,9