Our CRNC site links to some valuable articles on careful puppy buying and responsible breeding.  This article seeks to provide some information without unnecessary duplication: 1) a convenient list of health and other issues to consider; 2) some important ways to assess the breeder you approach; and 3) a list of registries through which you may seek validation of health certifications.

    Introduction: Genetics and the secret of siblings: We have provided a short course in genetics on our club site because genetics determine so much about the puppy you buy – in terms of health, temperament, appearance, soundness and "type."  What we hope you will take from Mark Martin's piece is this: no one can tell merely by looking what a dog used for breeding "carries" that may contribute to the characteristics of its offspring (even though the trait does not appear in the dog itself). There are certainly genetically carried problems that may be apparent in a dog (and therefore disqualify it from any responsible breeding program).  A bad heart or bad hips or aggressive temperament or obvious physical faults not caused by trauma or disease are examples.  And there are certainly traits – such as Landseer coloring – that are apparent and tell you something of what the dog may produce without disqualifying the dog from a responsible breeding program.
     But it is impossible to tell by looking (or even by invasive testing) that a dog does not "carry" bad temperament, the potential for a bad heart or hips or any of the other health problems that are common in Newfoundlands (and most large breeds).  The one possible exception is cystinuria [described below] – the one health problem of concern in dogs for which there is at least a claim for a genetic test.  If this claim is sound (but some clearances for "clear" dogs have been withdrawn when they've produced afflicted puppies), you can tell by testing a dog whether it carries the genetic material which may yield an afflicted pup.  Except for cystinuria, as Mark notes, you can tell what a breeding pair carries only by "test breedings."
     Before you say that no one in their right mind would expect breeders to do "test breedings" before producing a litter for sale, consider this: Every breeding is a test breeding.  Each member of the breeding pair came from a litter, and the breedings that produced the parents of the puppies you're looking at may also have produced other litters (i.e., litters with the same parents).  It is not unlikely that there have been prior breedings between the parents of your proposed pup.  They are all "test breedings," because the more you know about the litter mates and other siblings of the parents and about any previous progeny of this pair, the more you know about what genetic risks come with your puppy.  A responsible breeder keeps track of this and selects breeding stock accordingly.  For example, a responsible breeder will not breed the most gorgeous and sound champion if the breeder knows that dog had a litter mate (or other full sibling – one with the same parents) that had SAS.  And a knowledgeable puppy buyer will want to know about the parent's siblings and any previous litters.  Note that the traditional "horizontal" pedigree omits many dogs whose genetic characteristics are important to predicting the likelihood of genetically carried traits.  That's why the Orthopedic Foundation for Animals stresses the importance of the "vertical pedigree," showing siblings of parents and of grandparents instead of just the ancestors of a litter.   [Vertical vs. horizontal may seem counterintuitive if you are used to seeing generations displayed for humans -- where ancestors are higher up the chart than descendants; with pedigrees, ancestors are displayed to the right, so a "vertical" pedigree includes their siblings].
     Again, genetics is a matter of statistical probabilities.  Until and unless we can test for every genetically carried trait, breeders and buyers have a shot at predicting the health and other traits of puppies only if they collect and evaluate as much information as possible about the apparent genetic traits of siblings of the breeding pair and of their ancestors.

1) Health and other issues to consider: Here is a chart that lists the major issues affected by genetics in Newfoundlands and many other large breeds.  (For information on all of the genetic issues in the breed, and how they compare to other breeds, see the "Genetics Directory" on NoPuppyMills.com.)   The columns belowindicate that ideally the breeder and buyer should have information about these issues in all the indicated groups of relatives of the puppies (but don't expect any breeder to have all of this information):

      Note that temperament and appearance are at the end of the chart.  These are certainly influenced by genetics, and the relevance of siblings and probability is the same as with genetically linked health problems.  The internet provides an enormous source of information on all of the health issues.  One obvious place to start is the NCA Health and Longevity pages on the NCA site.  The OFA and Sweetbay have on-line databases that make researching dogs, their parents, their siblings, and their ancestors remarkably easy -- click here for instructions.
     Hips and elbows have to do with the structural soundness of dogs.  Perhaps the most prevalent disabling condition in Newfoundlands is hip dysplasia, a lack of proper fit between the bones of the hip joint that can lead to lameness to the point of crippling.  Elbow dysplasia is a similar problem, with similar results, on the dog's front end.  Patellar luxation is a condition in which the kneecap pops out of place, again leading to lameness and loss of function. Your best source of information on hips, elbows, and patellas is the Orthopedic Foundation for Animals (OFA).
      Cardiac problems, including subvalvular aortic stenosis, also referred to as subaortic stenosis or SAS, are common in the Newfoundland, and are clearly genetically linked.  SAS is a condition every breeder should check for before releasing a puppy to a buyer; the condition causes a heart murmur that may be detectable by a veterinarian.  SAS inflicted dogs may exhibit sudden death, or exercise intolerance, fainting, rear limb weakness, coughing, rapid breathing, or shortness of breath.  A dog with "mild" SAS can produce a puppy with severe SAS.  Again, responsible breeders do not use breeding stock whose siblings exhibit any SAS.
Cystinuria is a genetic defect rendering the kidney unable to process cystine (an amino acid) correctly.  The unprocessed cystine in the urine clumps into crystals or stones in the bladder which can cause irritation, infection, and blockage of the urinary tract.  It usually takes years for symptoms to develop.  Although some dogs may have the trait and suffer no symptoms whatever, the condition can also be fatal.  This is the one genetic health problem for which there is at least a claimed genetic test.  Surgery or diet may manage the condition in afflicted dogs, but there are downsides to either approach.
    CERF is the Canine Eye Registration Foundation.  Its very existence is testament to the prevalence of inherited eye disorders in dogs, and Newfoundlands are no exception.  Cataract is a clouding of the lens that can lead to blindness; it can be congenital,  early onset (juvenile cataract), or late onset.
     Many forms of cancer are increasingly common in Newfoundlands and other large breeds.  There seems to be general agreement that propensity for cancer is inherited.  And cancer is an increasingly common end-stage illness in geriatric dogs.  Cautious buyers would avoid a litter with a parent that had siblings with early-onset cancer.
     Canine thyroid disease can certainly be inherited.  Its symptoms include lethargy, mental lassitude, dull coat, weight gain, constipation, diarrhea, skin infections, skin odor, hair loss, greasy skin, dry skin, cold intolerance, reproductive problems, aggression, and more.  It may be manageable with hormone therapy.
     Bloat, also known as gastric dilatation-volvulus or GDV, is a condition in which the stomach swells with solids, liquids, and gases, causing great stress on the dog.  In its commonly severe form, the stomach twists on its axis (gastric torsion), ensuring that the condition cannot be reversed without heroic intervention.  Bloat requires immediate medical care; it is often fatal, and survivors often suffer continuing heart problems due to the stress that bloat inflicts on the heart.  The propensity for bloat is quite probably genetic, and likely connected to structure.  If several members of a previous litter (with different owners) of the breeding pair, or one or more siblings of both members of the breeding pair, suffered from bloat, it would certainly be reasonable to fear that the puppies would be more likely than most to encounter bloat at some point in their lives..
     Allergic dermatitis, also known as canine atopic dermatitis, results from immune system hypersensitivity, with symptoms ranging from merely annoying to severe itching, sores, and disabling distress.
     Laryngeal paralysis is a loss of function in the larynx, often progressive, with resulting breathing problems that can vary from minor to life threatening.  In extreme cases, oxygen deprivation can lead to death.  The dog is typically exercise intolerant, and suffers substantial distress when unable to obtain sufficient oxygen.  Surgery is an option, but substantially elevates the risk of inhalation (aspiration) pneumonia.
     Most people simply assume that Newfoundlands do not have temperament problems, but the truth is that the breed can include individuals that are aggressive or overly shy – and hence quick to engage in fear biting or other unfortunate behaviors. Even within the range of acceptable personalities, "temperament" includes variations in attitude that can make quite a difference in the enthusiasm with which a dog approaches working activities such as water rescue or agility, those requiring focus such as tracking, or those that call for the mellow "family dog" open to anything from children or other dogs. Genetics play a role in temperament, and the same rules of prediction apply.
     "Function" captures the movement and agility of a dog, and is determined in large part by its conformation and soundness.  The breed is supposed to be agile in water and on land, but it is hardly a given that any Newfoundland puppy will grow to be able to excel at such activities as water rescue and agility.  At the lower extreme, of course, hip, elbow, patella, and other health problems may make a dog lame or otherwise incapable of participating in any working activity – or even to go up and down stairs.  But even a sound and healthy dog may be less than ideal it its gait, agility, and endurance, and genetics certainly has a role here.   All other things being equal, a puppy from parents who themselves, or whose siblings and others in their line, racked up lots of working and agility titles are more likely than others to have the ability to excel at such tasks.
     "Appearance" covers a wide area.  Of course, at one level it means adherence to (or divergence from) the Newfoundland Breed Standard.  It also includes color, size, and markings.  If you are after a championship, of course you want to select a puppy likely to exhibit the appearances currently in vogue.  All other things being equal, a puppy from parents who themselves, and whose siblings and others in their line, racked up championships are more likely than others to possess the appearance promoted by the "standard" and the Illustrated Guide.
     Many argue that color is the very last thing that ought to be on a buyer's checklist.  There are many risks in breeding, and many important health and soundness issues should be addressed in any breeding program.  Which would you want your breeder to sacrifice to achieve your favorite color?

2.  How to size up a breeder: There are some great links addressing this issue, but here are a few more thoughts.
    First, go to the OFA and Sweetbay sites to learn what you can about the kennel's interest in health certifications (click here for instructions).
    Second, ask a breeder to describe their "breeding program."  If the question produces a blank stare (not to be confused with an attempt to assess your understanding of the topic before delivering an appropriately packaged response), run – do not walk – to another source.  Unfortunately, many breeders have "programs" consisting of nothing more sophisticated than "wouldn't it be nice for Bear and Osa to have puppies – they'd be so cute."  Chances are overwhelming that it won't be nice at all – because they haven't a clue as to the risks involved or how to minimize them, and will probably produce a litter of puppies sure to enrich veterinarians and darken the days of their heart-broken owners (or to swell the ranks of Newfoundlands needing rescue).
     What you should be looking for with a responsible breeder – one who at least understands that "every breeding is risky" and does not use that mantra to avoid responsibility for best practices – is a clear sense of priorities.  Where do health problems, breed ring performance, temperament, color, working ability fit in this breeder's choices.  Some would argue, for example, that those who breed for working events and obedience trials short change the chance to improve the breed as measured by the aesthetic measures of the breed standard.  Others would argue that by breeding to a standard that has evolved among breeders whose top priority is aesthetic conformation, the standard has deviated from the traits most consistent with the breed's purpose: water rescue, draft, and other working activities.  This tension between working and show priorities has divided many breed clubs; when the AKC threatened to certify the "border collie," many were furious at the prospect that breeding for the show ring would dumb down the breed.
     If this distinction is of importance to you, you will benefit from a careful reading of Newf Tide titlists, particularly the Annual of Titlists, to see which kennel names show up where.  In any event, get a good idea how careful the breeder is in screening for health and temperament problems.
     Third, pull out the chart above and use it as a checklist to ask the breeder what they can tell you about each of the issues in each of the categories of relevant relatives. If you've been to the OFA site, you already have some of the answers.  If your breeder doesn't understand why you want to know about siblings, for example, your breeder doesn't understand their importance – and can produce sound puppies only by accident!  If your breeder tells you they'd love to follow prior litters and siblings of the breeding pair but it would "invade the privacy of our puppy buyers," don't buy that nonsense.  Breeders commonly employ co-ownership agreements, restrict breeding rights, and all manner of controls to serve their interests; if they won't at least inquire and keep track of prior puppies from and siblings of the breeding pair, they are simply not breeding responsibly and you should go elsewhere. Responsible breeding cannot be based on the known traits of the breeding pair alone.
     Fourth, ask the breeder what the breeder expects of you as a puppy buyer.  A responsible breeder will insist that you have your dogs x-rayed at two years of age and report the results even if you have the dog neutered and have no plans on breeding it.  Remember, every breeding is a test, and your breeder should want to know and consider how your litter turns out as a measure of the success and failure of an ongoing breeding program, and as additional and important data relevant to whether the breeder should continue using the breeding pair or either member of that pair.  And if your breeder doesn't care because this is the last breeding for both parents, you should be interested in why this was the last breeding.  It may simply be because it's time to retire the parents, or it may be based on a concern for the success of the breeding that you'd like to know about.
    Finally, ask the breeder if you

3.  Health registries: The oldest and probably most useful registry is the Orthopedic Foundation for Animals, which registers hips and elbows, and, for dogs who have been tested for (whether or not they passed) hips, elbows, hearts, and cystinuria, a  CHIC (Canine Health Information Certificate).  The OFA site lists the certificate number along with any other tests submitted by the breeder, and cross references dogs with a CHIC.  And the OFA, understanding the importance of siblings, makes it easy to locate registered dogs that are siblings, ancestors, and even cousins of the dog you are researching. (Instructions on using the OFA site are here.) The Canine Health Information Center lists dogs with CHIC certificates. Again, be clear on this:  a CHIC number means only that a dog has been tested for the listed conditions, not that the dog has passed those tests!
    Be sure you understand what any registration does and does not establish concerning the subject dog.  Also be clear on what the registration certifies.  For example, the OFA has a panel that examines x-rays for hips and elbows, but the other information listed by the OFA is based upon certifications completed by other practitioners.  Most registrations therefore reflect only that someone outside the registry has provided information on a condition for a specific dog, and some, like CHIC, merely reflect that a dog has been tested for a condition without implying anything further.
    Note also that nothing requires all or any dogs to be registered.  An owner or breeder can choose not to register a dog that fails an exam.  So the absence of any given dog from a registry can mean that it wasn't tested, was tested and failed, or was tested and passed without being listed.  Obviously, registries would be far more helpful if they at least provided some means of estimating what proportion of dogs produced by a pair is represented by those listed.
    The OFA also lists some information from CERF, the Canine Eye Registration Foundation, which itself lists the many eye disorders common in many breeds and verifies health certifications by dog, registration number, and CERF number.  The OFA also includes historical data from the Institute for Genetic Disease Control, which has closed.
    Confirming other medical information may require certificates from a qualified veterinary source.  For example, a veterinary cardiologist can certify the absence of detectable SAS; an ophthalmologist can certify eye health, and cystinuria clearance may require certification from an appropriate lab, such as the University of Pennsylvania.
    Other Resources:
    Canine Health Foundation of the American Kennel Club
    Veterinary Genetics Services
    PennGen -- University of Pennsylvania School of Veterinary Medicine Section of Medical Genetics