Stages of Development in the American Mastiff

Researched and Written By Lisa Berberich 5B Ranch American Mastiffs


Let me start by saying that in any given litter different pups will have different personalities, much like human children in a family.  Your pup may experience these stages “to the max,” or you may not even notice your pup going through some of these stages.  Much of what I am sharing is coming from “My Smart Puppy” by Brian Kilcommons and Sarah Wilson (I highly recommend this book.  In fact, it’s on my “things to purchase before puppy pick-up day” list.)  I have added my own thoughts and observations and altered the time for the different stages based on the American Mastiffs I have raised and helped others to raise. 

Birth to 3 months:  The first 8 weeks of your pup’s life he/she is learning to be a DOG.  The pups go from blind, deaf pups weighing 1 – 1 ½ pounds at birth to 16-20 plus pounds of running, eating, playing bundles of fur by 8 weeks. 

This is also the age of attraction – the age of attraction runs from about 6-8 weeks until about 5-6 months.  During this stage, the pup’s natural instincts are to FOLLOW and to be submissive to the leaders of the family (human and 4 legged.)  Use this to your advantage.  Your pup will want to follow you closely.  This is the time to work on leash training and recall.

Somewhere during this time he/she will go through a sensitive/fear period.  Typically this lasts through the third month of life.  Noises, appearance of strange objects (new trash can, a box from Amazon), and strange dogs can send your pup scurrying for cover or hiding behind you.  This is a normal phase, and the best tactic for this time is to be calm, casual, and confident. Your pup will take his cues from you. 

Training Challenge: Your biggest challenge during this stage (besides house training) is the NIPPING!  Young pups explore everything with their mouths and they play with littermates with their mouths.  Nipping is a normal interaction for pups.  Your puppy packet will contain tips on how to teach your pup that humans are not teething rings.

Three to Six Months:  This is usually a great time for AM puppy owners!  Your pup is likely completely housebroken.  AM’s at this age are usually very eager to please owners.  They are irresistible with their tail wags and snuggles.  Growth is amazing during this age.  You’ll wake up and swear your pup grew overnight – and you will be right!  Teething is going full force during this time.  Gums will be sore and bleeding.  Your pup will be seeking relief for the discomfort.  You may even find some of those needle sharp babe teeth as they fall out.  Your 12 week update will contain some tips and suggestions for helping your pup through teething.

Training Challenge:  Your challenge during this stage is to keep it up!  You may think your pup is through the worst of puppyhood and you can let your guard down.  Please don’t!  Adolescence is right around the corner.  This is not the time to try letting your pup have free roam of the house while you are away.  This is not the time to think your pup is fully socialized and does not need to continue to go on regular outings.  Keep up with the training and socializing.

Six to Nine Months:  Whew!  Teething is over.  Your pup is housebroken.  Growth has slowed a bit (but is by no means over!)  Your AM pup is now a BIG pup.  That wonderful time of attraction is now over, unfortunately.  That same sweet pup that used to follow you everywhere and was eager to come running when he heard his name now suddenly appears deaf.  Your pup is becoming…..a teen!  Hang on, things are getting ready to become interesting.

Training Challenge: Keep things interesting for your pup.  If the only time you ever call your pup to the crate is to lock him up and leave for hours, why in the world would he want to come to the crate?  But what if, sometimes, when you call him to the crate it’s to enjoy the jackpot of treats?  Or a new toy? 

10 -18 Months:  This period, in my opinion, is the toughest age for AM owners. Your AM is entering full blown adolescence, and let’s face it – teens can be tough to be around at times.  Somewhere during this time your pup will discover his bark.  He will be more than happy to use that bark.  Visitors, dogs walking by, and new objects may all be met by a very impressive bark.  Your pup may regress in housebreaking – usually not accidents but chewing items that he/she knows are off limits.  These may include shoes, remote controls, door frames, drywall… this is the major destructive phase.  Your pup may also start becoming more protective during this time.  Protective barking and lunging at passersby during walks may occur during this time. 

Training Challenge – SURVIVING this time!  Seriously, this is the time that most AM’s are returned to the breeder.  You may go through periods where you are flat out angry at your dog.  You may question why you decided on this breed.  You may think you are in over your head.  When this happens, please CALL YOUR BREEDER.  We’ve been there, done that many many times.  This is a phase, and giving up on your dog now makes as much sense as giving up on your teenager.  You and your dog will get through this!  Think in terms of exercising your dog phyisically AND mentally during this time.  A tired pup is not a destructive pup. A pup that is being challenged mentally (training, obstacle courses, tricks) is using his/her intelligence for good, not evil!  Be sure to deal with any signs of protectiveness immediately.  Your pup should always know that YOU will handle strangers, new dogs, etc. and it is not his/her job to do so.

18 months -2 ½ years -  During this time your AM is exiting adolescence and becoming a young adult. I like to think of this time as “the college/young adult years.”  Once a teenager graduates from high school, he/she enters the adult world.  Usually this transition goes smoothly.  However, teens that made poor decisions in high school are likely to make poor decisions the first few years out of high school – and usually those decisions come with adult consequences.  Your AM is entering adulthood, but is not quite there yet.  If your AM was showing behavior issues as a teen, and these were not dealt with, you will likely see those behaviors significantly worsen.  Protectiveness, guarding instincts, and obsessive behavior can be problematic at this age. This is especially true for the AM that has a higher prey drive than is typical of our breed and has owners that did not deal with the undesired behavior when it first appeared.  Aggression in our breed is unusual, but in our experience this is the age when the over excited barking at new dogs or the fixation/obsession with certain objects (skateboards, for example) becomes a real safety issue. A 170-200 pound dog lunging at someone or something is SCARY.  Our dogs do not get any breaks in the behavior department.  A 10 pound toy poodle lunges at a kid on a skateboard and everyone thinks it’s funny.  Our dogs do it and animal control gets called.

 For the vast majority of AM owners, however this is the time when your AM  is becoming that gentle giant you dreamed of the day you picked up your pup.  Sometime during this stage you will discover that you can actually leave your dog in your house all alone for hours, and come home to NO surprises.  If you’ve continued with training and socialization, that magical day will come when you go out for a walk with your dog and other people stop you to admire how calm and sweet your big boy (or girl) is behaving. Your AM sits calmly by your side while you visit. He/she ignores the kids on bikes and the yip yip dog up the road.  Your finish your walk and sit on the couch to relax and your dog grabs a Nylabone and settles down by your feet to chew away while you watch t.v.  All your hard work has paid off, and you are sharing your life with your dream dog!