Reverse transcription real-time PCR for detection of porcine interferon α and ß genes.

A few studies provided convincing evidence of constitutive expression of type I interferons (IFNs) in humans and mice, and of the steady-state role of these cytokines under health conditions. These results were later confirmed in pigs, too. In line with this tenet, low levels of IFN-α/ß can be detected in swine tissues in the absence of any specific inducer. These studies are compounded by the utmost complexity of type I IFNs (including among others 17 IFN-α genes in pigs), which demands proper research tools. This prompted us to analyse the available protocols and to develop a relevant, robust, reverse transcription (RT) real-time polymerase chain reaction (PCR) detection system for the amplification of porcine IFN-α/ß genes. The adopted test procedure is user-friendly and provides the complete panel of gene expression of one subject in a microtitre plate. Also, a proper use of PCR fluorochromes (SYBR(®) versus EvaGreen(®) supermix) enables users to adopt proper test protocols in case of low-expression porcine IFN-α genes. This is accounted for by the much higher sensitivity of the test protocol with EvaGreen(®) supermix. Interestingly, IFN-ß showed the highest frequency of constitutive expression, in agreement with its definition of 'immediate early' gene in both humans and mice. Results indicate that the outlined procedure can detect both constitutively expressed and virus-induced IFN-α/ß genes, as well as the impact of environmental, non-infectious stressors on the previous profile of constitutive expression.

Retrospective data analysis of animal poisoning events in Liguria.

Intentional poisoning represents a serious risk to domestic and wild animals, and it can be an environmental and human health issue as well . This paper is a retrospective study, which covers a decade, based on animal poisoning cases and poisoned baits that were submitted for diagnostic examinations to the Veterinary Medical Research Institute for Piedmont, Liguria and the Aosta Valley (IZS-PLVA) in Liguria region. All data were collected through a passive surveillance system introduced in Italy by a decree of the Ministry of Health in January 2009. 43.2% of the animal poisoning cases were confirmed by toxicological analysis, whereas toxic agents were detected in 31.1% of the baits. The most affected animal species were dogs and cats, followed by synanthropic birds,. Only 4% of the total poisoning events analysed involved wild animals and cases of livestock poisoning were minimal. An increased number of cases in January, March, April and August was noticed, but no seasonal trend was detected. The most affected areas were the ones with the highest level of urbanization and population density. The major cause of the poisonings and the most common substances detected in the examined baits were anticoagulants whereas cholinesterase inhibitors, organochlorine pesticides and carbamates were detected in a minor number of cases. This study raises concerns about deliberate animal poisoning in ligurian region and highlights the necessity to fight this phenomenon as it endangers animals, humans and environment.

Impact of cadmium exposure on swine enterocytes.

We tested cadmium (Cd2+) effects on porcine IPEC-J2 cells, which represent an in vitro model of the interaction between intestinal cells and both infectious and non-infectious stressors. Accordingly, we investigated the effects of low (2 µM) to moderate (20 µM) concentrations of Cd2+, in terms of pro-inflammatory gene expression and protein release, as well as of infectivity in a Salmonella typhimurium penetration model. Our data showed a significant (P < .001) increase of intracellular Cd2+ after 3, 6 and 24 h of exposure with respect to levels at 1 h. These data showed the ability of IPEC-J2 to absorb Cd2+ as a function of both time and concentration. Also, the absorption of this heavy metal was related to a significant modulation of important pro-inflammatory messengers. In particular, down-regulation of IL-8 was associated with a significant decrease of Salmonella typhimurium ability to penetrate into IPEC-J2 cells, in agreement with a previous study in which an anti-IL 8 antibody could significantly inhibit Salmonella penetration into the same cells (Razzuoli et al., 2017). This finding demonstrates the ability of Cd2+ to affect the outcome of an important host-pathogen relationship. In conclusion, our study highlighted the ability of an environmental pollutant like Cd2+ to modulate innate immune responses in terms of chemokine release and gene expression, and susceptibility to microbial infections.

Time-course of antibody and cell-mediated immune responses to Porcine Reproductive and Respiratory Syndrome virus under field conditions.

Major discrepancies are observed between experimental trials of PRRS-virus (PRRSV) infection in isolation facilities and observations made in the field on farm. Owing to the above, a cohort study was carried out in a farrow-to-finish, PRRSV-infected pig farm to characterize the time-course of the virus-specific immune response in two groups of replacement gilts. Despite the occurrence of three and two distinct waves of infection in groups 1 and 2, respectively, the large majority of animals showed little if any PRRSV-specific response in an interferon-gamma release assay on whole blood, whereas non-specific responses were consistently observed. To rule out any possible bias of our test procedure, this was used along with an ELISPOT assay for interferon-gamma-secreting cells with the same reagents on a group of PRRS-virus infected pigs in isolation facilities. A very good agreement was shown between the two sets of results. Also, as opposed to the PRRS model, plenty of Pseudorabies virus-vaccinated pigs under field conditions scored positive in another experiment in the interferon-gamma release assay, ad hoc modified for the Pseudorabies virus. Our results indicate that under field conditions poor or no development rather than delayed development of the PRRS virus-specific interferon-gamma response could be the rule for a long time in non-adult pigs after PRRS virus infection. Housing and hygiene conditions, as well as heavy exposure to environmental microbial payloads in intensive pig farms could adversely affect the host's immune response to PRRS virus and partly account for the discrepancies between experimental and field studies.

Metabolic stress and inflammatory response in high-yielding, periparturient dairy cows.

Increased disease rates are commonly reported among high-yielding dairy cows in the transition period, extending from 3 weeks before to 3 weeks after calving, and characterized by the occurrence of an inflammatory response in terms of both positive and negative acute phase proteins (APP+ and APP-). To determine the above inflammatory response, the authors had developed the Liver Functionality Index (LFI), which defines the above condition on the basis of some APP- responses (albumin, cholesterol sensu stricto+bilirubin) during the first month of lactation. In this respect, low LFI values are associated to a high inflammatory response and vice versa. The relationship between LFI and inflammatory cytokine response was investigated from day -28 to day +28 with respect to calving in 12 periparturient dairy cows showing the six highest and six lowest LFI values within a cohort of 54 high-yielding dairy cows. The hypothesis being tested was that LFI and APP- on the whole could be used as readout of successful vs. non-successful adaptation to the transition period, with a strong association to disease occurrence. In fact, low LFI cows experienced many more disease cases (13 vs. 3 in high LFI Group) and related drug treatments till day +28. Interleukin-6 (IL-6) serum concentrations were always higher in low LFI cows (P<0.05 on day +28). The greater IL-6 levels were correlated with higher ceruloplasmin (APP+) and lower lysozyme serum concentrations (P<0.05 and <0.1, respectively). This latter finding was correlated with a clear role in vitro of lysozyme in a dose-dependent modulation of the inflammatory response of swine intestinal epithelial cells and bovine peripheral blood mononuclear cells. Hematological examinations showed no significant differences between the two groups under study. On the whole, our results indicate that LFI and LFI-related parameters could be used to identify cows at risk in the transition period toward an improved farm management. Also, our study indicates that disease cases in periparturient, high-yielding dairy cows are correlated with signs of accentuated IL-6 response and other markers of inflammatory phenomena. These likely start in the late lactation period or around dry-off, as suggested by our prepartal data, and proceed at much greater levels after calving.

Isolation and culture of pig tonsil lymphocytes.

Tonsils are secondary lymphoid organs that play an important role in host defense. The aim of our study was to develop reliable procedures for isolation and culture of pig tonsil cells, and to validate their possible use in functional immunoassays. Using our isolation procedure, we recovered on average 238.7 ± 107.1 × 10(6) cells per tonsil couple with a mean vitality of 89.8 ± 2.7%. These values significantly decreased 8 months after freezing at -80°C along with the subsequent spontaneous release of both IgA and IgG in culture. These results suggest to use pig tonsil cells within 2 months from thawing to maintain suitable conditions in terms of recovery, vitality and release of antibody in vitro. Tonsil mononuclear cells also showed the ability to secrete antimicrobial peptides and to respond in vitro to immunological stimuli. On the whole, our study has defined operating conditions for tonsil processing, control of bacterial contaminations, time limits of storage at -80°C, as well as for evaluating polyclonal Ig production in vitro. Such procedures are likely to be of some importance in studies on regional immunity and in the development of large animal models for biomedical sciences.

Clinical chemistry parameters of piglets at weaning are modulated by an oral, low-dose interferon-alpha treatment.

Clinical chemistry parameters were investigated in piglets weaned at 22 and 28 days. The effects of an oral, low-dose interferon (IFN)-alpha treatment at weaning were evaluated as well. The trial was carried out on 59 piglets from the same farm, allocated to three groups: the first and the second groups were weaned at 28 and 22 days of age, respectively; the third group was weaned at 22 days and orally treated at weaning with IFN-alpha at a low dose (1 IU human lymphoblastoid IFN-alpha /kg body weight in drinking water) for 10 consecutive days. The results of the field trial confirmed that weaning is one of the main stressing events for pigs at intensive farms. In particular, these findings are based on a dramatic increase in serum haptoglobin levels after weaning in the three groups under study. Results also indicated that early weaning at 22 days implies higher environmental adaptation. In such animals, an oral, low-dose IFN-alpha treatment gave rise to a peculiar, negative, acute-phase response (reduced levels of serum albumin) and to significantly lower alpha-globulin concentrations in sera. Taken together, IFN-alpha was shown to modulate inflammatory responses to early weaning stress.

Mycotoxin detection in infant formula milks in Italy.

After birth, infant formulas constitute an important or often sole food source for infants during the first months of life. In this study, a survey on the presence of aflatoxin M1 (AFM1) and ochratoxin A (OTA) in the 14 leading brands of infant formulas marketed in Italy was conducted. Mycotoxins were determined by immunoaffinity column clean-up and high-performance liquid chromatography (HPLC) with fluorescence detection. AFM1 was found in two of 185 samples, but at levels below the European legislation limit of 25 ng l(-1). OTA was detected in 133 (72%) samples (range = 35.1-689.5 ng l(-1)). It has been observed that OTA contamination was 80% in the ready-to-use preparations and 63% in the powdered samples. The Scientific Committee for Food (SCF) reviewed the toxicology on OTA and concluded that it would be prudent to reduce exposure to OTA ensuring that exposure is towards the lower end of the range of tolerable daily intakes of 1.2-14 ng kg(-1) body weight day(-1). OTA was also evaluated by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and a provisional tolerable weekly intake (PTWI) of 100 ng kg(-1) body weight was established. The OTA levels in pre-term ready-to-use infant formulas were sufficient to cause a higher OTA intake than the suggested TDI. The results point out the need to perform controls for prevention programmes especially when attempting to identify risk markers of the infant feed quality.