I am thinking of adopting a pup (mutt) from a shelter but need a small
dog.  Is the size of the dog determined by the mother or is the size
just as likly determined by the father or as I suspect by both?

Dear ddbbdd-ga;

Thank you for allowing me to answer your interesting question.

A dog's size as an adult is determined partly by his or her genes, but
we cannot discount the fact that it is also partly influenced by
environmental factors such as its health, its hardships and the food
it eats as a puppy and young adult.

The dog has 78 chromosomes, in 39 pairs, on which approximately
100,000 genes are located. This is known as a ?genotype? ? or the
overall picture of what the dog is to become. The ?phenotype?, or the
chromosomal recipe, if you will, for what the animal outwardly and
visually becomes (physically), is the part of the genotype that is
directly affected by the environmental factors.

The genes that the dog inherits from BOTH his parents ?CAN? have an
impact on what the dog eventually becomes, but this is not the case in
all instances. In other words, an autosomal dominant gene (will
override the autosomal recessive gene and the dog will take on that
dominant characteristic. The more autosomal dominant genes the animal
has from one of his parents the more likely he is to resemble certain
traits of that parent. In some cases a parent may pass on an
extraordinary number of autosomal dominant genes to its offspring and
despite the fact that the two parents are totally different breeds
with totally different characteristics, the offspring comes out
looking exactly like one parent and nothing like the other.

On several occasions I have personally seen litters of puppies from
different breed parents where some of them looked like the mother?s
breed, some looked like the father?s breed and some appeared to be
mixed (polygenic - traits determined by a few or many genes working in
concert).

As a rule, a dog?s weight is generally determined by diet. His genes
normally determine his height and length, and the autosomal dominant
gene will always determine which parent he is most likely to
physically resemble. Having been a professional police dog trainer in
the past, and one of my responsibilities was to shop and purchase
dogs, one of the handy shade-tree methods of judging a puppy?s future
size that I found to be somewhat reliable is the size and shape of
their feet. A young puppy with really big feet and/or really long and
splayed out toes will likely grow up to be a rather big dog (taking
into consideration, of course, what is deemed ?big? for his breed).
Another indicator in some breeds is the girth of the tail at the point
where it attaches to his posterior. In my experience a very thick,
muscular tail base is often an indicator that a dog has the potential
to grow up to be a large specimen for his particular breed or
combination of breed(s).


I hope you find that my research exceeds your expectations. If you
have any questions about my research please post a clarification
request prior to rating the answer. Otherwise I welcome your rating
and your final comments and I look forward to working with you again
in the near future. Thank you for bringing your question to us.

Best regards;
Tutuzdad-ga ? Google Answers Researcher



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Certainly everything tutz wrote is correct and answers the question as
asked - I would like to emphasize some practical advice which tutz did
mention.

As a former kennel owner (Bouvier des Flandres), I would like to point
out that a good way to judge the eventual size of a grown dog is to
look at the size of its feet.

Not infallible, but a good indication.

100,000 genes. That was the estimate of the number of genes in the
human genome. Now as it turns out, there are only 25-30 thousand.

Not only that, but only a few actually code for protein.

OK, golchocobo but what does that have to do with the size of a dog?

Whatever you do, don't go by the old wives tale of "The size of the
paw determines the size of the dog." I have seen enormous sized paws
on Basset Hounds but have never once seen one as big as a greyhound
when grown.

pxe - Ever seen a newfoundland puppy? Of course it depends somewhat on
breed, some breeds naturally have larger paws, but I've been a breeder
for years and it is no old wives tail.