PMID- 21831539
OWN - NLM
STAT- MEDLINE
DCOM- 20120330
LR  - 20181201
IS  - 1873-2542 (Electronic)
IS  - 0378-1135 (Linking)
VI  - 154
IP  - 1-2
DP  - 2011 Dec 29
TI  - Comparative pathogenicity of type 1 and type 2 isolates of porcine reproductive 
      and respiratory syndrome virus (PRRSV) in a young pig infection model.
PG  - 58-68
LID - 10.1016/j.vetmic.2011.06.025 [doi]
AB  - Porcine reproductive and respiratory syndrome virus (PRRSV) isolates are 
      classified in two different genotypes, based on genomic heterogeneity: type 1, 
      which comprises European type isolates, and type 2, which includes North American 
      type isolates. It is believed that members of both genotypes differ in some 
      biological properties including pathogenicity, however extensive studies 
      comparing isolates of both genotypes have never been carried out. The objective 
      of the present study was to compare the pathogenic properties of six different 
      PRRSV isolates, three of type 1 and three of type 2, in a young pig infection 
      model. For this purpose, a total of 105 3-week-old piglets were divided in 7 
      groups of 15 animals that were exposed on day 0 of the experiment to one of the 
      six isolates tested or were mock infected (negative control group). Clinical 
      signs and rectal temperatures were recorded daily and blood samples were taken on 
      days 3, 6, 9, 12, 15, 18 and 21 of the experiment. On days 7, 14 and 21 
      post-inoculation five animals per group were sacrificed, macroscopic lung lesions 
      were evaluated and different tissue samples were collected to determine viral 
      organic distribution. The results obtained indicate that type 2 isolates are more 
      pneumovirulent than type 1 isolates, as demonstrated by the recording of 
      respiratory clinical signs only in pigs exposed to type 2 viruses and by the 
      severity of macroscopic and microscopic lung lesions in those pigs. However, no 
      clear differences could be established between genotypes in systemic clinical 
      signs or viral load and viral distribution after challenge. These results support 
      the general idea that type 2 isolates induce more severe respiratory disease than 
      type 1 isolates.
CI  - Copyright (c) 2011 Elsevier B.V. All rights reserved.
FAU - Martinez-Lobo, F J
AU  - Martinez-Lobo FJ
AD  - Dpto. Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 
      28040 Madrid, Spain.
FAU - Diez-Fuertes, F
AU  - Diez-Fuertes F
FAU - Segales, J
AU  - Segales J
FAU - Garcia-Artiga, C
AU  - Garcia-Artiga C
FAU - Simarro, I
AU  - Simarro I
FAU - Castro, J M
AU  - Castro JM
FAU - Prieto, C
AU  - Prieto C
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20110701
PL  - Netherlands
TA  - Vet Microbiol
JT  - Veterinary microbiology
JID - 7705469
RN  - 0 (Antibodies, Viral)
SB  - IM
MH  - Animals
MH  - Antibodies, Viral/blood
MH  - Genotype
MH  - Lung/*pathology/virology
MH  - Porcine Reproductive and Respiratory Syndrome/pathology/*virology
MH  - Porcine respiratory and reproductive syndrome virus/genetics/isolation & 
      purification/*pathogenicity
MH  - Swine/*virology
MH  - Viral Load
EDAT- 2011/08/13 06:00
MHDA- 2012/03/31 06:00
CRDT- 2011/08/12 06:00
PHST- 2011/03/14 00:00 [received]
PHST- 2011/06/18 00:00 [revised]
PHST- 2011/06/23 00:00 [accepted]
PHST- 2011/08/12 06:00 [entrez]
PHST- 2011/08/13 06:00 [pubmed]
PHST- 2012/03/31 06:00 [medline]
AID - S0378-1135(11)00353-1 [pii]
AID - 10.1016/j.vetmic.2011.06.025 [doi]
PST - ppublish
SO  - Vet Microbiol. 2011 Dec 29;154(1-2):58-68. doi: 10.1016/j.vetmic.2011.06.025. 
      Epub 2011 Jul 1.