When I was asked to write on the subject of fading puppies, I decided, after some thought, that it would be best to examine three particular points. Firstly, what causes puppies to fade, secondly, what can be done to prevent the loss of puppies and thirdly, what action can be taken to help should it be necessary to call in a veterinary surgeon to investigate a problem. hopefully, this rather different approach will prove to be interesting, useful and of practical help.

But let's first try to identify the size of the problem. There is no doubt that most experienced dog breeders and veterinary surgeons will agree that fading puppies represent a real problem. Indeed surveys carried out over the years both in the UK and America have indicated that 20 - 30 % of puppies born alive and expected to reach maturity die before weaning age. That is bad enough but the problem is not spread evenly amongst kennels so that some breeders may lose 50,70 or even 100 % of puppies born. A recent survey carried out by the Animal Health Trust revealed a figure of 32 % , so the situation is still with us. Doubtless then there is an economic need to do something about the condition. that apart , if more puppies survive, then hopefully a more critical culling program could be established, leading to better stock in the long term - or is that a pipe dream?

CAUSE AND CLINICAL SIGNS

The first important point to stress in relation to cause is that there are a number of factors which alone, or in combination, can cause puppies to fade - the condition is, in scientific terms, multi - factoral. It is important to note that there is not just one simple cause of neonantal mortality in dogs. Therefore, the situation in which a number of puppies apparently healthy at birth but which fail to thrive and die before they reach 14 days of age is best referred to as " THE FADING PUPPY COMPLEX " ( FPC ) . That is the classical definition of the condition. Some other workers in this area have reserved the term " FADING PUPPY " for those puppies that die and no obvious cause of death can be found even after careful post mortem, including bacteriological and histological examination. That rather narrow definition may be acceptable to the pathologist but I would contend that it does little to help the breeder or the clinician. Thus I consider the earlier definition to be more practical and meaningful.

The second point to stress is that ' the clinical signs shown by fading puppies are to allintent and purposes the same regardless of cause'. All fading puppies essentially look alike despite the fact that the cause may be different.

In the typical case puppies appear vigorous and healthy at birth and suck the colostrum ( first milk ) avidly for the first 24 hours. They then become progressively weaker, may make no further attempt to suck and lose weight rapidly. There heads may sway from side to side, they paddle feebly with their forelimbs at the mammary glands, and lack the strength to find, or hold on to, a teat. Periods of rigidity with straightening of the forelimbs and spine may occur just before death. Very often affected puppies become restless, cry continually and the bitch may push them to one side. Eventually respiration becomes labored and prolonged spells of breath-holding may occur, accompanied, occasionally, by the passage of blood in the fasces and urine. Not all litter-mates are necessarily affected and the bitch concerned may or may not produce fading litters in subsequent pregnancies. From the veterinary surgeon's point of view this means that looking at puppies in the nest or listening to owner descriptions does not materially help in respect of diagnosis, treatment and the prevention. To make progress one has to dig deeper, ask a lot of questions and play detective.

What then causes puppies to fade?

Those agents that have been incriminated as being involved in the causanation of the complex fall, not unexpectedly, into five main groups:

1. Micro-organisms

Bacteria

2. Parasites

Principally Toxoplasma Toxocara canis Viruses

I would have liked to give a percentage incidence related to each cause but unfortunately firm figures are not available. However, it is possible to make an informed guess, as follows, based on an amalgamation of information contained in literature:

Consider 100 puppies born - 8 will be still - born and 30 will fade. Of the 30 fading 5 [17%] fade through infection; 1 [3%] fades through Toxocara infestation; 5 [ 17%] fade as result of bad mothering including hypothermia; 2 [6%] fade through dystokia {difficult birth}; 5 [17%] fade from congenital defects and in 12 cases [40%] no obvious cause will be apparent.

But let's look at each of these causal factors in more detail starting with:

1.micro - organism

(a) BACTERIA

As far as most bacteria are concerned, the scientific tests (called Koch's postulates) which need to be carried out to prove the cause of disease has not yet been satisfied and there seems to be a need for much more basic research. Many of the attempts to reproduce the disease in puppies using a number of different bacteria have been unsuccessful but this does not necessarily mean that they are not involved with the a etiology of the FPC, since some triggering or precipitating factor may be needed in order to set the disease process in train.

I consider that there is reasonable evidence to suggest that at least three species of aerobic bacteria are involved in the complex. b-hemolytic streptococcal {BHS}, E. coli and Brucella spp. Other bacteria such as pasteurella, bordetella, proteus and pseudomonas have been isolated but less frequently, making it difficult to assess their significance as causal agents.

As far as streptococci are concerned it should be remembered that these organisms are commonly found in a high percentage of normal dogs. Fortunately, there is a laboratory test which can be used to tell whether a streptococcal isolate is likely to be harmful, or not, to dogs, and really this should always be carried out.

At one time infection with BHS was considered to be the prime cause of puppy deaths. Many breeders are familiar with the organism and only too often shut their minds to other possibilities. Now we know somewhat better.

Until it is established conclusively which strains of E. coli are capable of producing disease diagnosis must be guess work. As a rule of thumb, however, only haemolytic strains should be considered significant. It should, however, be borne in mind that strains of this organism, which are normally saprophytic, ie. bacteria that are normally present and not causing any harm, may become pathogenic in puppies which have not received colostrums.

Brucella canis infection has been well describe in the literature as a cause of fading puppies in America. Indeed in that country it has led to considerable problems in kennels breeding beagles for experimental purposes. In Feb.80 a report appeared in the veterinary literature indicating that the infection does not exist here. Antibodies were found in two Doberman bitches with American ancestry. This was indeed sad news and means that the possibility of this infection being involved must be borne in mind when outbreaks of fading puppies, abortion and infertility in bitches and orchitis in males are being investigated, particularly in breeds with a large imported component. Bitches may be infected with other Brucella strains like Brucella abortus, in the main cause of abortion in cattle, but they do not seem to cause outbreaks rather individual infection.

As far as diagnosis is concerned, let me say straight away that there is no specific sign or change that is diagnostic of any of these bacterial infection which I have mentioned so far. But there are small differences and if the clinician is willing to spend time observing and abstaining a good case history and carrying out detailed PM examinations of puppies, then it is possible to have a fair idea as to which particular infection may be involved and to take the relevant samples to prove that is the case. Little reliance can be placed on samples taken for bacteriological examinations unless they are fresh. More substantial evidence is obtained if swabs are taken from the vagina of the bitch, the prepuce of dogs and from the throats of dogs and bitches, and the same organism is found in all these sources. So it pays to take a number of swabs.