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In order for Neva Masquerade to be as healthy a breed as possible, it is recommended that we carry out health tests on our breeding animals. The tests we do are:HCM-andPKD scan, FIV and FeLV tests,parasite test sent to SVA  as well as blood grouping via DNA test atMyCatDNA or similar lab.
Unfortunately, there is no health program for the breed from SVERAK, but the above are recommendations from our breed ring FörNEM. 

I follow these in my breeding work in Corda Dreams'.

Below follows some  information about the diseases that it is recommended that we test against. 

HCM - hypertrophic cardiomyopathy in cats 

Pawpeds applies the Health Program for HCM-Hypertrophic Cardiomyopathy to Siberian cat and Neva Masquerade. 

This means that HCM scanning is recommended at one year of age, then every year up to age 3, then follow-up at age 5 and 8.


HCM, or hypertrophic cardiomyopathy, is an inherited disease. It is the most common heart disease in cats and the symptoms usually start at 2 to 4 years of age. 

Symptoms can also be detected earlier, especially if both parents had the disease. Male cats are affected more often than females, and the disease occurs in both pedigree cats and domestic cats.

HCM is a disease that can be difficult for the owner to detect. The symptoms can be decreased appetite, fatigue and shortness of breath. The most common way to suspect the disease is in connection with the annual health check when the vet listens to the cat's heart. Murmurs or irregular heartbeats may be heard, in which case the cat should undergo an ultrasound examination of the heart, during which the diagnosis can be made. The changes in the heart consist of the heart muscle becoming thickened. This means that the cavity in the heart becomes smaller and a smaller amount of blood is pumped out into the body with each heartbeat. Since the blood must transport oxygen to the body, symptoms of poor oxygenation in the form of poor stamina and shortness of breath arise. 

The disease can also lead to small clots of clotted blood forming in the heart and being carried out into the body. When the blood clot lodges in a narrower blood vessel, often where the corporal artery divides to the hind legs, it causes paralysis and pain in one or both hind legs. This is called a blood clot or thrombus. 

Thickening of the heart muscle can also be caused by high blood pressure and/or too high a metabolism. When diagnosing HCM, it is important to examine the cat for these conditions as well. 

Unfortunately, you cannot cure or prevent the change in the heart itself, but you can prevent the development of blood clots by giving blood-thinning medicine. If it is high blood pressure or a high metabolism that is the cause of the thickening of the heart muscle, the development can be slowed down when these conditions are brought under control. Once a cat has been diagnosed with HCM, it should be checked approximately every six months. Cats treated with blood-thinning medication should come in for a check-up once a year. 

Fortunately, most cats given the correct medication and regular check-ups can live long lives with the disease without suffering from it.

SOURCE: Blue Star

PKD-Polycystic Kidney Diseases

PKD is an autosomal dominant kidney disease. Which means the cat only needs to inherit one copy of the mutated gene to have PKD. However, it can also inherit it from two parents with PKD. Previously, it was not believed that these kittens survived.

The cats are born with a number of cysts on the kidneys that can neither be more nor less. However, they grow with the cat. If they are many and/or become large, the cat has kidney failure. The cysts contain fluid. Over time, the cysts can knock out normal kidney function and increase abdominal pressure

Symptoms of the disease are:

- Feeling of pressure/pain in the abdomen
- Kidney stones
- Impaired ability to concentrate urine
- Hypertension
- Hematuria
- Uremic symptoms

PKD is not included in any breed Health program according to SVERAK. In the past, the Persian was hit hard by it. The disease was discovered in our breed in January 2019 and then was started a big job among us breeders in Sweden. Breeding animals is recommended to be ultrasound-scanned. Breeding animals that test positive may be removed from breeding.

The signatory works actively to map the disease in Sweden and has an open register for PKD-scanned cats. Where everyone is invited to submit their test results.

Source: Lennart Nilfors, Leg. veterinarian,  Internal medicine

FIV – Feline Immunosuppressive Virus 


FIV in cats is a virus that has similarities to HIV in humans. The virus cannot be fought by the body's immune system and sooner or later the cat becomes ill. FIV attacks the cat's white blood cells, just like FeLV (see below), leading to a weakened immune system. Symptoms are seen more often in older cats, and FIV affects males more often than females. 


As FIV impairs the immune system, the cat becomes more sensitive to various infections and the symptoms can vary greatly. 

When the cat first becomes infected, it is not always that the pet owner notices any symptoms in the cat. However, the cat can become ill for a short period with a fever and reduced general condition. 

The cat is then healthy for a period, usually several years, before the disease breaks out (compare HIV and AIDS). 

In the end, the cat becomes seriously ill from infections that normally would not have affected the cat. Sometimes the cat can become symptom-free and then become ill for periods. Generally, the cat tends to get worse and worse. 


Symptoms can e.g. be: 

·Respiratory tract infection

·Inflammation in the oral cavity 



·Skin problems

·Enlarged lymph nodes 



Transmission routes 

The virus is spread via saliva and blood and is most often transmitted by a bite from an infected cat. On occasion, FIV can also be transmitted via mating or via the uterus to kittens. The latter can contribute to reproductive problems. The greatest risk of the kittens becoming infected is if the mother cat becomes infected during pregnancy. 

Outdoor cats have the greatest risk of becoming infected as they fight with other cats more often than indoor cats do. 


Diagnosis and treatment 

Antibodies can be detected using a blood test. An infected cat carries the virus with it for the rest of its life, but it can take up to eight weeks before the antibodies have time to form. If it is suspected that the first sample was taken in the acute stage of the infection, it may therefore be necessary to take new samples a little later to rule out FIV. As the immune system is destroyed in infected cats, there are sometimes no antibodies left in the blood in the final stages of the disease. Then it is also not possible to diagnose the disease with the help of this blood test. 

An infected cat can live healthy for many years before becoming ill. If the cat is diagnosed with FIV, however, it is very important that the cat is kept indoors and not allowed to meet healthy cats to avoid the infection being passed on. 

It is also good to avoid the cat becoming stressed to reduce the risk of triggering illness. 



FeLV – Feline Leukemia Virus 

FeLV is a virus that attacks the bone marrow and the cat's white blood cells, which are the body's defense against various diseases. Because the white blood cells are infected, the virus then spreads with the blood and infects other tissues in the body. 

Kittens and older cats are most sensitive. Many cats resist the virus thanks to an effective immune system and get rid of the virus within a few weeks/months. For those who do get sick, it can take months to years before the cat gets sick and shows symptoms. 


The symptoms can be divided into tumor diseases (blood, bone marrow and lymph cancer) and diseases that result in a weakened immune system. The virus can also cause reproductive problems. 


Symptoms vary but can include be: 


·Difficulty breathing 

·Poor appetite and emaciation 

·Inflammation in the gums and mucous membranes in the mouth 

·Pale mucous membranes 

·Impaired immune system which can lead to secondary diseases in above all respiratory tract and 

the gastrointestinal tract 

·Early fetal death and infertility 


Transmission routes 

FeLV is most common where there are many cats. Infected cats are mainly infected via saliva, e.g. via bites or that they lick each other. They also shed a small amount of virus via feces and urine, but saliva is the main route of transmission. Kittens can be infected in the womb as well as through the mother's milk. 

Healthy cats can be carriers. Some cats can carry the virus latently for several years, i.e. carry the virus without being sick or being a carrier. This latent period ends either with the cat fighting the virus or with the virus being activated and the cat becoming a chronic carrier. 


Diagnosis and treatment 

To detect the virus, an analysis of a blood sample is required. It usually takes at least 2 blood tests a few months apart to distinguish the cats that have cleared the infection from those that have a persistent infection. In the cats that have a latent infection, the virus cannot be detected. 

Treatment is difficult, but there is now medicine, given as injections under the skin, which can reduce the risk of illness and premature death. There are also vaccines that can protect the cat against the virus. However, the vaccine should not be used too frequently as it increases the risk of unusual tumor diseases. 

Feline Neonatal Isoerythrolysis

Cats have three different blood types, A, B and AB. A is the most common blood type while AB is very rare. A is dominant over B and AB, while AB is dominant over B. Cats with blood group B only have a predisposition for B (thus are homozygous), while cats with blood group A can also carry predispositions for blood groups AB and B. The cat's different blood groups can cause problems in connection with blood transfusions.

However, a much more common problem caused by different blood types is feline neonatal isoerythrolysis. Feline neonatal isoerythrolysis occurs if a female cat with blood group B is mated  with a male cat who has blood group A and produces kittens with blood group A. Cats with blood group B form strong antibodies against blood group A, while cats with blood group A only have weak antibody formation against blood group B. These antibodies will be present in the milk of the lactating female cat. When the kittens suckle, the antibodies are taken up by the intestine and enter the blood, where they begin to attack the kittens' red blood cells, which break down.

Becomes weaker after birth

The kittens are strong and healthy when they are born, but then become progressively weaker. The symptoms can vary in strength. Some kittens with blood group A are not affected at all, while others die quickly before developing any symptoms. Typical symptoms are that the kittens become weak and do not want to nurse. The breakdown of the blood cells causes the kittens to become jaundiced and the urine to turn brown-red. In kittens that are mildly affected and survive, the tail tip tissue may die (necrosis) at one to two weeks of age. The earlier the symptoms appear, the worse the prognosis. The antibodies can only be absorbed by the intestine during the first day of the kitten's life.

Feline neonatal isoerythrolysis can thus be avoided by removing pups with blood group A from a female with blood group B during the first day after birth. You either let them wean from a female cat with blood type A or you give them milk replacer. After a day, the cubs can be returned to the mother without risk.

Symptoms - then it may be too late

Once symptoms appear, it is usually too late to save the kitten. If you know that the female cat has blood type B and is mated with a male cat that has blood type A, you should therefore prevent the kittens from lactating for 24 hours. If both the father and the mother have blood type B, all the children will also have blood type B and in such cases there will be no problems with neonatal isoerythrolysis.

The frequency of cats with blood type B varies between different breeds. Blood type B is very rare in domestic cats but is quite common in some cat breeds. The spread also varies geographically, depending on which lines have been bred. Breeds where a large proportion of cats with blood type B (25-50 percent) have been found in the US are British Shorthair, Devon Rex and Cornish Rex. In Abyssinians, Somalis, Persians and Sacred Burmese, blood group B was found in 10-20 percent of the cats tested. Blood group AB is even rarer than B, but kittens with blood group AB are also exposed to neonatal isoerythrolysis just like kittens with blood group A.

In breeds with a high frequency of blood type B, there may be reason to routinely determine the cat's blood type before the first mating. Blood group determination can be done through a serological test of a blood sample. Nowadays, it is also possible to determine blood group using a DNA test (test of the genetic material). With a DNA test, it is possible to find out whether a cat with blood group A is a carrier of blood group B. However, it is not possible to distinguish between blood group A and AB with a DNA test. You can also use a quick test to find out the blood group directly at the time of the test. The disadvantage of the rapid test is that you cannot find out what antibody titer (amount of antibodies in the blood) the cat has, and it is also not possible to see whether cats with blood group A are carriers of blood group B.


Mortality among kittens cannot be completely avoided, but if you suspect that an abnormally high number of kittens are dying, you should definitely take action. You should think through your routines in terms of vaccinations, deworming, hygiene and prevention of the spread of infection.

An important step in the investigation is to have dead kittens autopsied. You can either contact your vet for help or you can send the kitten yourself for an autopsy along with a detailed account of the process. It is important that the kitten is autopsied as soon as possible after it has died in order to get a good result from the autopsy. If the child is stillborn, the placenta and amniotic membranes should also be sent with it. Information on how to go about submitting an animal for necropsy can be found on SVA's website (

If you do not send the kitten right away (for example, if it dies on a Friday and risks being left in the mail over the weekend), you should cool it to refrigerator temperature as soon as possible. Kittens to be necropsied should not be frozen as the tissues will then be destroyed.

Worth the money

Although an autopsy may seem expensive, it can be money well spent if it leads to a solution to the problem. If you suspect that feline neonatal isoerythrolysis may be the reason why kittens die, you should find out which blood group the female cat has. If she has blood type B and is mated with a male cat with blood type A, the cause of the problem has probably been found. You can then take measures so that more kittens do not die from the same cause again.

Doctor of Veterinary Medicine Eva Axnér works at the Department of Reproduction at the Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Science at the Swedish University of Agriculture in Uppsala.

Source: Agria

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