Challenger High-Protein Kibble Alpine Ranch Beef, Lamb & Pork Recipe Dry Dog Food
Verified Jun 16, 2026
This is a high-protein dry dog food featuring multiple animal protein sources, including deboned beef, lamb, pork, salmon meal, turkey meal, and chicken meal. It uses organic oats, barley, and millet as its main carbohydrates, with added omega-rich chicken fat, taurine, probiotics, and antioxidant-rich fruits and vegetables. The formula is designed for puppies and adults of most sizes, but is not intended as a sole diet for large-breed puppies over 70 lb expected adult weight.
This is a nutritionally dense, meat-forward kibble with a very solid protein level and a nice mix of animal proteins, making it a good fit for active dogs and most growing puppies under large-breed size. The use of organic ancient grains provides complex carbohydrates and fiber instead of relying on legumes or potatoes, and added taurine, omega fatty acids, and probiotics are supportive for overall health. It’s not appropriate as a complete diet for large-breed puppies, and the multiple common proteins mean it isn’t ideal for dogs with food sensitivities.
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At a Glance
What "not formulated for" means
Life stages this food isn't certified complete and balanced for, based on its AAFCO statement.KibbleLab Review
Strengths
- High protein (35% minimum) from a variety of named animal sources, including fresh meats and meat meals, which support lean muscle in active dogs and growing puppies.
- Uses organic oats, barley, and millet as primary carbohydrates instead of peas, lentils, or potatoes, avoiding the legume-heavy grain-free pattern that has raised heart-health questions in some dogs.
- Added taurine (0.2%), omega-3 and omega-6 fatty acids, and antioxidant sources like pumpkin, blueberries, and spinach provide supportive nutrients for heart, skin/coat, and immune function.
- Includes Bacillus coagulans probiotic to help support a healthy gut microbiome and digestion, and is formulated to meet AAFCO standards for all life stages except large-breed growth.
Considerations
- Not suitable as a complete and balanced diet for large-breed puppies expected to reach 70 lb or more as adults; those dogs should be on a large-breed growth formula.
- Contains several common protein allergens (beef, lamb, pork, chicken, turkey, salmon), so it would not be a good choice for dogs needing a limited-ingredient or single-protein diet for suspected food allergies.
- Calorie density is fairly high at about 438 kcal per cup, so portion control is important, especially for less active dogs, to help prevent unwanted weight gain.
Full Ingredient List
Ingredients and analysis reflect manufacturer data at the time of our last update and can change without notice. Always check the actual product packaging before feeding.
Ingredient filtering helps identify compatible options but is not a substitute for a veterinary elimination diet.
Top 5 Ingredients Explained
01
Deboned Beef
Deboned beef is used primarily as a high-quality animal protein and palatability enhancer in dog and cat foods, supplying essential amino acids, bioavailable iron and B vitamins that support muscle maintenance, energy metabolism and overall health. Because it is deboned it reduces the risk associated with feeding whole bones, but pet parents should note beef can be a common allergen and variable fat content increases calorie density, so it should be part of a formulated, balanced diet rather than fed alone.
02
Deboned Lamb
Deboned lamb is used in pet foods primarily as a high-quality animal protein source for dogs and cats, supplying essential amino acids, B vitamins, iron and zinc while lacking the calcium associated with bone-in meats. It can be a palatable option and a potential novel protein for animals with food sensitivities, but owners should note lamb can be higher in fat and calories than lean meats and raw or undercooked lamb may carry pathogens unless properly processed, so check product labels and consult your veterinarian for specific dietary needs.
03
Salmon
Salmon is commonly used as a high-quality animal protein and rich source of omega‑3 fatty acids (EPA/DHA) in dog and cat foods, supporting skin and coat condition, joint and cognitive health, and overall muscle maintenance. While very nutritious, salmon can be an allergen for some pets and raw salmon may pose risks from parasites, thiaminase-related thiamine loss, and region-specific pathogens (e.g., salmon poisoning); owners should avoid feeding uncooked bones and consider sourcing to minimize contaminant and sustainability concerns.
04
Turkey
Turkey is commonly used as a primary animal protein in dog and cat foods, offering highly digestible, high‑quality protein and supplying essential amino acids along with B vitamins, phosphorus and zinc to support muscle maintenance and metabolism. Its fat level varies by cut so products can be lean or richer; some pets may develop allergies to poultry, cooked bones are hazardous, raw meat carries bacterial risk, and owners should rely on balanced commercial formulations (and ensure adequate taurine for cats) if turkey is a main ingredient.
05
Pork
Pork is used in pet foods primarily as a high-quality animal protein and flavor enhancer, supplying essential amino acids, B vitamins (especially B12 and niacin), iron and zinc, plus fat for calorie-dense energy; it can be suitable for both dogs and cats when balanced in a complete diet. Because pork can be relatively high in fat, it may be inappropriate for pets requiring low‑fat diets or those prone to pancreatitis, some animals may have sensitivities to pork, and raw or undercooked pork can carry parasites or pathogens so it should be properly processed or cooked.
Nutritional Breakdown
How to read As Fed versus Dry Matter
As fed shows the numbers straight off the label, water included. Dry matter removes the water so you can compare a wet food and a dry food fairly.What is calorie density
How many calories the food packs per unit. Denser foods mean smaller portions for the same calories.Product Details & Brand
Product Specs
AAFCO Nutritional Adequacy
What is AAFCO
Association of American Feed Control Officials. It sets the nutritional
adequacy standards US pet foods are measured against.
What is AAFCO
Association of American Feed Control Officials. It sets the nutritional adequacy standards US pet foods are measured against.Brand
Nulo is a premium pet food brand focused on grain-free and high-meat-protein recipes for dogs and cats. It is positioned as a performance and wellness brand, emphasizing quality ingredients, ancestral diet alignment, and the inclusion of probiotics to support digestive health.
Visit NuloManufacturer
Nulo partners with trusted manufacturing facilities in the United States and Canada that maintain high food safety standards including HACCP and SQF certification. Nulo oversees ingredient sourcing and quality control to ensure nutritional accuracy and consistency across batches.
Manufacturing details are compiled from public sources and not independently verified; they may not reflect contract manufacturing or co-packing.
Recall History
Nulo Challenger High-Protein Kibble Alpine Ranch Beef, Lamb & Pork Recipe Dry Dog Food has no recalls since 2014.
Source: FDA Pet Food Recall Database · Monitored daily
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Frequently Asked Questions
Has Nulo ever been recalled?
We have no recalls on record for Nulo. We monitor the FDA Pet Food Recall Database daily.
How does KibbleLab rate foods?
Our scores are based on ingredient composition, nutritional profile, AAFCO compliance, and health considerations. We don't penalize by-products, grains, or synthetic preservatives. Brands cannot pay for higher scores.
Is KibbleLab a substitute for veterinary advice?
No. KibbleLab provides data-driven food analysis, not medical advice. Always consult your veterinarian before making dietary changes, especially for pets with health conditions.
KibbleLab provides informational content only. This is not veterinary advice. Always consult a qualified veterinarian before changing your pet's diet.
KibbleLab may earn affiliate commissions through product links. No one can pay for a higher score, or to change what we recommend for your pet.
Product data sourced from manufacturer websites, AAFCO statements, and FDA recall database. Last verified dates reflect our most recent data check.
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