And it's never too late to socialize
I disagree with Dani and Brigetta's Mom. (Usually I agree with Dani but on this I must differ.)
There are "
criticial periods" in the early development of dogs -- brief windows open during which certain social experiences with other dogs or people MUST occur or the dog will be ever deficient. (In later decades these have been called
"sensitive periods" recognizing that
some partial modifications can
sometimes be made given enough practice.)
Scott & Fuller defined these periods in their EXCELLENT, MOST SIGNIFICANT OF ALL RESEARCH STUDIES ON DOGS EVER DONE OR EVER WILL BE (a 20? year longitudinal study on 5 dog breeds,
"Genetics & the Social Behavior of Dogs"). IMO, it was so important because it --
-- was a major factor in helping sway Psychology from its obsession with Learning/Experience as being the primary influence of behavior
-- brought developmental phases into prominence in understanding behavior
-- contributed ENORMOUSLY to an understanding of how to raise puppies during their first 6 months of life
I think there's a good (but not guaranteed) possibility that your Lab's experience with the Beagle may have helped him gain some socialization skills that MAYBE can be drawn on to expand the capacity for socialization.
Let me quote from S&F:
"In the period of socialization there are two basic rules for producing a well-balanced and well-adjusted dog. The first of these is that the ideal time to produce a close social relationship between a puppy and his master occurs between 6 and 8 weeks of age. This is the optimal time to remove a puppy from the litter and make it into a house pet. If this is done earlier, especially at 4 weeks or before, the puppy has little opportunity to form close relationships with other dogs. It will form close relaionships with people but may have difficulty adjusting to its own kind even in mating or caring for puppies. On the other hand, if primary socialization with people is put off to a much later period (the outside limit being about 12 weeks), the social relationship with other dogs may be very good ....[providing the puppy has had those socialization experiences]....
but he will tend to be timid and lack confidence with people.
Since S&F's monumental work, later studies have defined the phases/periods slightly better but the overall pattern has withstood the test of 50+ years of scientific scrutiny and been validated.
Of all people, I should have known of this before buying Bess at 5 weeks age. I was the graduate lab instructor for comparative psychology and my principle professor for my PhD was a comparative psychologist. I'd been very excited by the work of Tinbergen, Lorenz, von Frisch, Hess, and Scott & Fuller. BUT 5 years later, when it came to buying a Lab pup, Bess, none of that registered.
Bess DID have a little relation with another dog in our home when she was about 6 months old but "Jumper" (a Boxer mix) met an untimely death collding with a car after several months.
But for the rest of her life, Bess never played with other dogs or expressed interest in them. She totally ignored them and I'm quite sure she thought she was a person and that dogs (other than Bess) were an alien species.
Currently, at our weekly Saturday afternoon LabFests (2-3 PM) altogether we've had maybe 40-50 Labs trickle through.
Those Labs which have NOT had early experiences with other pups during the proper phase for dog socialization do NOT know HOW to play with other Labs. Typically they stand around and bark at other Labs -- as if asking "
play with ME?" -- but they don't know how to engage with the other.
IF the dog has not had the proper socialization experiences during the desired critical times then remedial experiences AFTER those phases may help some/a little but
never will be as effective as those experienced within the proper phases.