Infection with different Neospora caninum strains causes differences in the glycosylation pattern in the uteri and placentae of Neospora caninum-infected heifers.

Neospora caninum is an obligate intracellular parasite that causes abortion in ruminants. Different strains produce differences in the severity of disease outcomes. These differences may cause physiological or pathological changes in cells, modifying the intercellular interactions and intracellular transport pathways that could be evidenced by identifying the terminal sugars. This study aimed to characterize the oligosaccharide pattern in the bovine placenta and uterus after infection with tachyzoites of three different strains of N. caninum (Nc-1, Nc-6 Argentina and Nc Spain-7) during early gestation. Fourteen heifers were inoculated intravenously on day 70 of gestation with 2 × 108 N. caninum tachyzoites and samples of placentae and uteri were analysed by histology and lectin histochemistry. In the infected groups, severe placentitis was associated with changes in lectin binding in the vascular endothelium by Lens culinaris agglutinin (LCA), Pisum sativum agglutinin (PSA) and Ricinus communis I (RCA-I) lectins, in the epithelial cells of the endometrial glands by RCA-I, Dolichos biflorus agglutinin (DBA), succinylated wheat germ agglutinin, peanut agglutinin (PNA), concanavalin-A (CON-A), LCA, PSA and Phaseolus vulgaris erythroagglutinin (PHA-e), and in the trophoblast layer by PNA, CON-A, LCA, PSA, PHA-e, soybean agglutinin, RCA-I, DBA and Bandieraea simplicifolia agglutinin (BSA-I). The results suggest that N. caninum causes changes in the glycosylation pattern in the maternofetal interface tissues and might cause abortions in early gestation due to changes in the cellular structure of the placenta.

Serologic evidence of HoBi-like virus circulation in Argentinean water buffalo.

HoBi-like pestiviruses (also known as bovine viral diarrhea virus 3) have been sporadically reported from naturally infected cattle in Brazil, Asia, and Europe. Although HoBi-like viruses seem to be endemic in Brazilian cattle and buffalo, they have not been studied in the other countries of South America to our knowledge. Herein we report serologic results of buffalo from 12 large farms in Argentina located near the Brazilian border. These buffalo were not vaccinated against pestiviruses. Our results indicate that HoBi-like virus may be circulating in the northeastern region of Argentina given that half of the analyzed animals showed high levels of neutralizing antibodies against the pestivirus. The HoBi-like seropositive animals were also checked for neutralizing antibodies against BVDV-1a, BVDV-1b, and BVDV-2, and in most cases these animals had low levels or no detectable antibodies against these other pestiviruses. Our study suggests a need for continued pestivirus surveillance in Argentinean cattle and buffalo.

First report of isolation and molecular characterization of bubaline herpesvirus 1 (BuHV1) from Argentinean water buffaloes.

Herpesviruses have mainly co-evolved with their hosts for millions of years. However, bovine herpesvirus 1 (BoHV1) and related ruminant alphaherpesviruses have been reported to cross the species barrier. Bubaline herpesvirus 1 (BuHV1) is an alphaherpesvirus closely related to BoHV1 and BoHV5. According to the serological cross-relationships between ruminant alphaherpesviruses, several surveys have studied the occurrence of BoHV1-related virus infection in wild and domestic ruminant species. Recent studies in Argentina showed an increase in serological prevalence against BoHV1 related viruses in water buffaloes (Bubalus bubalis) population. The aim of this study was to investigate the presence of related ruminant alphaherpesvirus in the Argentinean water buffalo population. BuHV1 was successfully isolated from 5 out of 225 buffaloes analyzed. One isolate was obtained from nasal secretions, and the others were from vaginal swabs. The buffaloes belonged to four different farms located in northeastern Argentina. The isolates were characterized as alphaherpesvirus by direct immunofluorescence using FITC-anti-BoHV1 IgG. Restriction analysis performed with BamHI and BstEII on the complete genome showed differences between the isolates and those from BoHV1 and BoHV5 subtypes. Phylogenetic analysis on both UL27 and US6 showed similarity in tree topology. While three of the isolates grouped together with sequences of BoHV5, two other isolates clustered separately. Genetic analysis of eight concatenated sequences from all isolates and references strains showed high nucleotide sequence identity between BuHV1 and BoHV5. While three of the isolates clustered together with the BoHV5 reference strain, the last two isolates were closely related to an Australian BuHV1 strain. To our knowledge, this is the first report on the isolation and molecular characterization of BuHV1 in South America. Phylogenetic analysis suggested that two different BuHV1 lineages circulate in the Argentinean water buffalo population.

Detection of antibodies against Brucella abortus, Leptospira spp., and Apicomplexa protozoa in water buffaloes in the Northeast of Argentina.

Water buffalo industry has become a profitable activity worldwide, including the Northeast of Argentina (NEA). However, research on diseases affecting this species is scarce. The aim of the present study was to detect antibodies against Brucella abortus, Leptospira spp., Neospora caninum, Toxoplasma gondii, and Sarcocystis spp. in 500 water buffalo cows from five ranches (100 animals each) in the NEA. Serum samples were tested for B. abortus by fluorescence polarization assay, Leptospira spp. by microagglutination test, and N. caninum, T. gondii, and Sarcocystis spp. by indirect fluorescent antibody tests. Overall, the proportion of seropositive animals was 6.4, 22.2, 42.2, 25.4, and 50.8 % for brucellosis, leptospirosis, neosporosis, toxoplasmosis, and sarcocystosis, respectively. The proportion of seropositive animals for all diseases was statistically different among herds (p < 0.05). Statistical differences were also detected among age groups for brucellosis and neosporosis (p < 0.05). The detection of specific antibodies to B. abortus, Leptospira spp., and several Apicomplexa protozoans in water buffaloes in the NEA is reported in this study.

Isolation and characterization of bovine parainfluenza virus type 3 from water buffaloes (Bubalus bubalis) in Argentina.

BACKGROUND: Parainfluenza virus type 3 (PIV3) was isolated from dairy buffaloes (Bubalus bubalis) naturally affected with respiratory and reproductive clinical conditions. RESULTS: Examination of nasal and vaginal swabs collected from 12 diseased buffaloes led to the isolation of three paramyxovirus isolates from two animals. Antigenic, morphological and biological characteristics of these three isolates were essentially similar to those of members of the Paramyxoviridae family. Antigenic analysis by direct immunofluorescence and cross neutralization test placed these isolates together with bovine parainfluenza virus type 3 (BPIV3). Nucleotide and amino acid phylogenetic analysis of partial matrix gene sequences of the buffalo isolates and six field BPIV3 isolates from bovines in Argentina were studied. Buffalo isolates were similar to genotype B (BPIV3b) while the six BPIV3 isolates were similar to genotypes A (BPIV3a) and C (BPIV3c). CONCLUSIONS: This is the first characterization of BPIV3 in water buffalo.According to the samples analyzed, in Argentina, the genotype B was found in buffalo and the genotypes A and C were found in cattle.