| Abstract | U razdoblju od 2015. do 2020. godine sa Klinike za zarazne bolesti Veterinarskog fakulteta
Sveučilišta u Zagrebu prikupljeno je 211 obrisaka rektuma i uzoraka izmeta mačaka koje su
pokazivale znakove akutnog gastroenteritisa. Za sve životinje prikupljeni su i podaci o nacionalu,
anamnezi, kliničkoj slici, tijeku i ishodu liječenja. U uzorcima je dokazivana prisutnost sojeva
CPPV-1 metodom lančane reakcije polimeraze. Rezultati pretrage dali su uvid u prevalenciju
zarazne panleukopenije mačaka u životinja koje su pokazivale kliničke znakove akutnog
gastroeneritisa na području grada Zagreba, te ona iznosi 61,61% sa stopom preživljavanja od
55,55%. Nakon određivanja nukleotidnog slijeda umnoženih odsječaka genoma ustanovljeno je
kako su u populaciji mačaka na području grada Zagreba prisutna oba soja CPPV-1, (FPV 73,33%,
CPV-2 22,67%). Dokazano je kako tip virusa CPV-2c dominira sa 76,47%, dok se CPV-2c nalazio
u 11,76% uzoraka, za 11,76% uzoraka nije bilo rezultata. Anamnestičkim podacima prikupljenim
prilikom prvog pregleda ustanovljeno je da su mlađe životinje češće oboljevale od soja FPV
(prosjek od 0,79 godina), dok je soj CPV-2 bio češći kod starijih životinja sa prosjekom od 4,5
godine. Krvna slika pokazala je značajnu eozinopeniju i trombocitopeniju u krvi pozitivnih
mačaka. Kod FPV soja ustanovljene su izmjene aminokiselina na pozicijama 91, 232, 303 (mjesta
vezanja protutijela) i 562 (neizravno uzrokuje promjene u konformaciji). Filogenetskom analizom
stabla dobivene su lokalna i međunarodna skupina, što se može objasniti postojanjem univerzalnog
modela evolucije nastalog zbog globalizacije, pa su tako sojevi s različitih kontinenata međusobno
slični. |
| Abstract (english) | Feline panleukopenia (FPL) is a very common clinical disease syndrome in cats caused by
infection with Carnivore protoparvovirus-1, it is also the oldest known viral disease in cats. Both
feline parvovirus (FPV) and canine parvovirus (CPV-2) can cause FPL. Kittens usually die within
the mortality rate of 90% despite vaccination. So far no research on CPPV-1 prevalence and
epizootiology in cats in the Republic of Croatia has been done.
The aim of this study was: 1) To collect the data on the prevalence of CPPV-1 strains on the
territory of the Republic of Croatia, to determine risk factors and clinical manifestations of
infection to facilitate the identification of infection and targeted treatment by veterinary
practitioners. 2) Phylogenetic analysis of the virus, which has not been conducted in our country
so far to provide insight into the molecular epizootiology of infection with feline panleukopenia.
3) Determining the direction of CPPV-1 evolution in cats and the significance of the amino acid
alterations of viral proteins for the pathogenicity and efficacy of immunoprophylaxis.
MATERIAL AND METHODS
During the period from 2015 to 2020, 211 rectal swabs and fecal samples of cats that showed signs
of acute gastroenteritis were collected from the Clinic for Infectious Diseases of the Faculty of
Veterinary Medicine, University of Zagreb. Along with the fecal samples, data on medical history,
clinical picture, course, and treatment outcome were collected for all the animals included in this
study. The presence of CPPV-1 strains in fecal samples or rectal swabs was detected with the
polymerase chain reaction. Determination of the nucleotide sequence of amplified sections of the
genome was done by MEGA 7 software.
RESULTS
The overall prevalence of feline panleukopenia in cats that showed clinical signs of acute
gastroenteritis in the city of Zagreb was 61.61% with a survival rate of 55,55%. It was proven that
both strains of CPPV-1 were present in the cat population in the city of Zagreb (FPV=73.33%,
CPV-2=22.67%). Furthermore, CPV-2c virus type was shown to dominate with 76.47%, while
CPV-2c was found in 11.76% of samples and 11,76% had no results of virus type. Data on the
disease history collected during the first examination revealed that younger animals were more
likely to be infected with the FPV strain (average of 0.79 years), while the CPV-2 strain was more
common in older animals (average of 4.5 years). CBC showed statistically significant eosinopenia
as well as significantly reduced platelet counts in positive cats. In FPV strains, amino acid changes
were found at positions 91, 232, 303 (receptor binding sites) and position 562 which might
indirectly cause surface conformational changes. Phylogenetic analysis of the tree gave us two
large groups, local and international, which can be explained by a universal model of evolution
caused by globalization, that makes strains from different continents similar to each other.
CONCLUSIONS
The prevalence of 61,61% of CPPV-1 in the city of Zagreb was high and it was consistent with all
the published results in other countries. The percentage of CPV-2 strains (22,67%) among the
positive samples was higher than expected. Significant eosinopenia, as well as significantly
reduced platelet counts in the CBC of positive cats, could serve for diagnostic purposes. In FPV
strains, amino acid changes were found at positions 91, 232, 303, and 562. Amino acid residues
91, 232, and 303 are antibody binding sites, while amino acid residue 562 might indirectly cause
surface conformational changes. Phylogenetic analysis of the tree provided insight into the distribution of sequences into two large groups, local and international, which can be explained by
the existence of a universal model of evolution as a result of globalization, so strains from different
continents are similar to each other. |
