How Big Will an English and Italian Mastiff Mix Puppy Be?

by Serena Styles Google
    Mastiff puppies grow at an exceedingly fast rate during their first year.

    Mastiff puppies grow at an exceedingly fast rate during their first year.

    Jupiterimages/ Images

    There are several different breeds of the mastiff dog, including the English mastiff and the Italian, or Neapolitan mastiff. While only a pure-bred mastiff can be registered with most kennel clubs, mixing the two breeds will produce a fine mastiff puppy. Because it is a mix between two breeds, you can estimate the growth rate of the puppy based upon each breed's normal weight. However, the end weight of your puppy will depend upon the size of the mother and father.

    First Four Weeks

    After the first four weeks of growth, an English and Neapolitan mastiff mix puppy will likely weigh between three and five pounds. Around one month of age, the mother, or dam, might begin to wean the puppies off milk. As they switch to solid foods, you will see a significant increase in weight gain and growth spurts.

    Second Month

    In the second month of growth, an English and Neapolitan mastiff mix puppy will begin to put on weight rapidly. Now that the puppy is eating solid foods, its weight can increase to a range of eight to 15 pounds. The puppy will become more active in its second month, but you must take care not to let it run too much or jump on and off surfaces. The rapidly increasing weight raises the risk of the puppy injuring itself during strenuous play.

    Third and Fourth Months

    In the third and fourth months, the English and Neapolitan mastiff mix puppy's growth rate will skyrocket. It will weigh between 20 and 40 pounds and can gain as much as five pounds per week. The puppy's appetite and activity levels will increase alongside its growth rate. However, in its first two years of life, you must not take the dog on long runs or walks, as this can damage its joints.

    Fifth and Sixth Months

    In the fifth and sixth months of your English and Neapolitan mastiff mix puppy's life, it will likely weigh between 45 and 70 pounds. At this point in its life, you will begin to get an idea of how large it will be when it is an adult. During these two months, your puppy might continue to gain five pounds, or more, each week. This is normal. However, if you worry your puppy is gaining too much weight, discuss it with your veterinarian at your puppy's next checkup.

    Seventh through 12th Months

    In the second half of your English and Neapolitan mastiff mix puppy's first year, its growth rate will slow slightly. By the end of its first year, it will likely double what it weighed at 6 months of age. Anywhere between 90 and 140 pounds is normal as it nears the end of its first year.


    • "Mastiff: A Comprehensive Guide to Owning and Caring for Your Dog"; Christina de Lima-Netto; 2003
    • "Mastiffs"; Kim Campbell Thornton; 2009
    • "Mastiff Secrets: The Ultimate Guide: Everything You Need to Know About Buying, Raising, and Caring for a Mastiff"; Elvio Romeo; 2009

    Photo Credits

    • Jupiterimages/ Images

    About the Author

    Serena Styles is a Colorado-based writer who specializes in health, fitness and food. Speaking three languages and working on a fourth, Styles is pursuing a Bachelor's in Linguistics and preparing to travel the world. When Styles isn't writing, she can be found hiking, cooking or working as a certified nutritionist.

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