RESUMEN

Tuberculosis has a negative economic impact on buffalo farming, and it poses a potential threat to human health. Interferon-gamma (IFN-γ) plays a central role in protection against mycobacterial diseases, illustrating the importance of T-cell mediated immune responses in tuberculosis infection. Recently, the expression of Caspase-3, a critical executor of apoptosis, in M. tuberculosis-specific IFN-γ+CD4+ T cells was used as a new marker to distinguish active from latent tuberculosis infection in humans. The aims of this work were to develop a whole blood flow cytometric assay to detect the production of IFN-γ and the activation of Caspase-3 by CD4+ T lymphocytes from water buffalo and to evaluate whether these parameters can discriminate between healthy and M. bovis naturally infected buffaloes. A total of 35 Italian Mediterranean buffaloes were grouped in two groups: uninfected and M. bovis infected (based on the results of antemortem diagnostic tests: single intradermal tuberculin (SIT) and ELISA IFN-γ tests). Whole blood was incubated for 6 h with tubercular antigens: PPD-B, PPD-A, ESAT-6/CFP-10 and a new mix of precocious secreted antigens (PA). Our results showed a significant increase in the percentage of IFN-γ+CD4+ T cells in infected compared to the uninfected animals after each stimulus. Improved sensitivity of the assay was obtained by including the stimulation with the new mix of PA. Interestingly, we observed a concomitant decrease in percentage of Caspase-3+CD4+ T cells in M. bovis infected animals compared to the control healthy ones, regardless of the stimulus used. Overall, these results showed that M. bovis infection activates CD4+ T lymphocytes to produce IFN-γ and at the same time causes a concomitant decrease of Caspase-3 activation in CD4+ T cells. This study for the first time in water buffalo describes the development of a whole blood flow cytometric assay for the detection of IFN-γ producing CD4+ T cells and proposes the expression of active Caspase-3 as an additional bovine TB biomarker. Although further studies are needed to better understand the mechanisms of Caspase-3-mediated cell death during tuberculosis, our data can help to better understand the cellular immune response to M. bovis infection in buffalo species.

Asunto(s)

RESUMEN

Salmonella enterica subsp. enterica Serovar Enteritidis is one of the major pathogens associated with enteric diseases in animals and humans. Thus, due to the importance of Salmonella spp. infections for animal production and public health, the aim of the present study was to describe the first detection of S. enteritidis in an aborted water buffalo fetus in southern Italy by characterizing the phylogroup profile and the antimicrobial susceptibility of the isolated pathogenic strains. The different clinical manifestations of salmonellosis in animals include diarrhea, abortion, pneumonia, septic arthritis, meningitis, and others, depending on the virulence of the serovars, infectious dose, and host immunity. This study reports the first case of abortion caused by Salmonella enterica subsp enterica serovar Enteritidis in water buffalo (Bubalus bubalis) in the Campania region, southern Italy. Complete necropsy was performed on the aborted water buffalo fetus under study, and samples and swabs from different organs were collected. Samples were processed by microbiological and molecular analyses to detect bacterial, viral, and protozoarian pathogens possibly responsible for abortion. Whole genome sequencing (WGS) was carried out to further characterize the isolated S. Enteritidis strain. Our findings highlight the crucial role of S. Enteritidis as a potential abortive agent in water buffalo and its presence should therefore be investigated in cases of bubaline abortion.

RESUMEN

The identification of cross-reactive monoclonal antibodies (mAbs) that recognize orthologous leukocyte differentiation molecules (LDM) in buffaloes has overcome a major impediment limiting research on the immune response to pathogens and development of vaccines. As reported, two pilot trials were conducted to accomplish two objectives: (1) demonstrate that multiparameter flow cytometry can be conducted equally well in buffalo with mAbs directly and indirectly labeled with fluorochromes in research and (2) flow cytometry can be used to compare and extend studies on diseases of economic importance to buffalo using bovine viral diarrhea virus (BVDV) as a model pathogen. Pregnant buffalo cows were infected with BVDV-1 at 81 (trial 1) and 203 (trial 2) days post artificial insemination and flow cytometric evaluations were performed at 0, 3, 4, and 14 days after infection (dpi). Fluorochrome conjugated mAbs were used in trial 1, and fluorochrome conjugated goat isotype specific anti-mouse antibodies were used to label mAbs in trial 2. Flow cytometric analysis revealed a transient lymphopenia occurs during the 1st days following infection similar to lymphopenia reported in cattle. In particular, significant differences were observed between pre- and post-infection absolute values of T lymphocytes (-56%, P < 0.01). CD21+ B lymphocytes (-65%, P = 0.04), and Natural Killer cells (-72%, P < 0.001). No significant differences were observed in monocytes and neutrophil absolute values, or the CD4:CD8 ratio. Animal health status was followed until 15 days after calving. No clinical signs of infection were observed during the evaluation period, however, animals in trial 1 developed complications later the infection. One cow aborted at 57 days post-infection, the second cow developed a prolapse a day after calving and died. These two animals also showed a more pronounced lymphopenia in comparison with animals infected at 203 days of pregnancy (e.g., -77 vs. -22% T lymphocytes at 3 dpi, respectively). The pilot studies have demonstrated that it is possible to use multicolour multiparameter flow cytometry to study the immune response to pathogens affecting the health of buffalo.

RESUMEN

Listeria monocytogenes (LM) is the causative agent of listeriosis in both animals and humans, representing one of the most severe food-borne diseases in humans. Out of 13 serotypes, only three (i.e., 1/2a, 1/2b, and 4b) are responsible for 95% of human outbreaks of listeriosis. Ruminants have been hypothesised to represent the main natural reservoir for this pathogen and to be involved in the transmission of Listeria to humans. During pregnancy, listeriosis in ruminants cause various reproductive disorders as well as abortion. However, little is known about abortion due to LM in water buffaloes (Bubalus bubalis). In this study, we report for the first time the detection of LM in a water buffalo foetus in the region of Campania, Italy. Complete necropsy was performed, and samples and swabs from the abomasum, kidneys, liver, lungs, and spleen were collected. Microbiological and molecular analyses were carried out to detect bacterial, viral, and protozoarian abortive pathogens. The results revealed the presence of LM in the liver, lungs, and abomasum, and no other agent was detected. Isolation was confirmed by biochemical and molecular tests. Molecular serotype characterisation was performed, and serogroup IVb was identified. In conclusion, because of the zoonotic implications of our findings, this report highlights the importance of including LM in the diagnostic panel in cases of bubaline abortion.

RESUMEN

The water buffalo (Bubalus bubalis) is important to the economy of several countries in Asia, and South America and there are also isolated herds in Europe. In India, buffalo is the main dairy animal. Coccidiosis due to Eimeria is an important cause of diarrhea in livestock worldwide. Eimeria species are generally considered host specific. More than 11 Eimeria species are considered common in buffaloes and cattle (Bos taurus, Bos indicus). Of the numerous species of Eimeria in cattle, Eimeria bovis, Eimeria zuernii, Eimeria auburnensis and Eimeria alabamensis are considered pathogenic in cattle, but there is no report of their pathogenicity in naturally infected water buffaloes. Instead, Eimeria bareillyi has been documented to be the main pathogenic species in buffalo; it is not transmissible to cattle. There are many reports of Eimeria infections in water buffaloes, scattered in many local journals, and there are conflicting life cycle data on Eimeria species in buffalo. The objective of this paper is to summarize information on history, validity of Eimeria species, life cycle, pathogenicity, prevalence, epidemiology, diagnosis and control of coccidiosis in buffalo.

Asunto(s)

RESUMEN

There are uncertainties concerning the identity and host species specificity of Sarcocystis species of the water buffalo (Bubalus bubalis) and cattle (Bos taurus). Currently, in cattle three species are recognized with known endogenous stages, viz.: S. cruzi (with canine definitive host), S. hirsuta (feline definitive host), and S. hominis (primate definitive host). Recently, a fourth Sarcocystis species with an unknown life cycle has been reported from cattle. In the water buffalo, four species of Sarcocystis have been described: S. fusiformis (feline definitive host), S. buffalonis (feline definitive host), S. levinei (canine definitive host), and S. dubeyi (definitive host unknown but not cat or dog). Besides, there are studies of Sarcocystis infections in buffalo and cattle from China with results that are difficult to interpret and validate. For example, some of the studies report transmission of Sarcocystis species between cattle and buffalo, but steps to preclude exogenous exposures were not reported. A species of the water buffalo, 'S. sinensis', was proposed at a Chinese national conference in 1990, and published as an abstract without figures and with no archived type specimens for verification. The International Code of Zoological Nomenclature Articles 9 and 10 state that "abstracts of articles, papers, posters, text of lectures, and similar material when issued primarily to participants at meetings, symposia, colloquia or congress does not constitute published work"; therefore, S. sinensis is a nomen nudum.

Asunto(s)