Antonio D’Angelo

Effects of housing and short-term transportation on hormone and lymphocyte receptor concentrations in beef cattle

The experiment was designed to evaluate the effects of housing system and short-term transportation on the pituitary and adrenal response and on blood progesterone concentrations of beef cattle. Since the use of steroid hormones in farm animals has been banned in the EU (Council Directive 96/22/EC), it seems important to study the possible modifications in serum progesterone concentrations induced by stress in cattle. Thirty-two, 6 months old male Piedmontese beef cattle (16 reared in a littered loose house, Group A, and 16 housed in a littered tying stall barn, Group B) were blood sampled at T1 (6 months old), T2 (12 months old), T3 (18 months old, before transportation to the slaughterhouse) and T4 (after transportation to the slaughterhouse) in order to measure hormonal concentrations and lymphocyte glucocorticoid (GR) and β-adrenergic (β-AR) receptor concentrations. Circulating hormone concentrations were measured using commercial radioimmunoassay kits, whereas lymphocyte receptor density was determined through binding assays. In beef cattle housed in tie stall barn a significant increase in serum cortisol concentration was observed at T3, whereas there was no effect of the housing system on blood progesterone concentrations. Short-term transportation caused a significant increase in blood cortisol and catecholamine concentrations in both groups, whereas lymphocyte GR and β-AR significantly decreased in Group A. Our data confirm the activation of the hypothalamic-pituitary-adrenal axis and the catecholaminergic system in short-term transportation and suggest that the stress-induced increase in circulating progesterone concentrations does not exceed the limit established by pending legislation.

Characterization of the upper and lower respiratory tract microbiota in Piedmontese calves

BackgroundThe microbiota of the bovine upper respiratory tract has been recently characterized, but no data for the lower respiratory tract are available. A major health problem in bovine medicine is infectious bronchopneumonia, the most common respiratory syndrome affecting cattle. With this study, we used 16S rRNA gene sequencing to characterize and compare the microbial community composition of the upper and lower respiratory tracts in calves.ResultsThe microbiota of the upper (nasal swab [NS]) and the lower (trans-tracheal aspiration [TTA]) respiratory tracts of 19 post-weaned Piedmontese calves with (8/19) and without (11/19) clinical signs of respiratory disease, coming from six different farms, was characterized by 16S rRNA gene metabarcoding. A total of 29 phyla (29 in NS, 21 in TTA) and 305 genera (289 in NS, 182 in TTA) were identified. Mycoplasma (60.8%) was the most abundant genus identified in both the NS (27.3%) and TTA (76.7%) samples, followed by Moraxella (16.6%) in the NS and Pasteurella (7.3%) in the TTA samples. Pasteurella multocida (7.3% of total operational taxonomic units [OTUs]) was the most abundant species in the TTA and Psychrobacter sanguinis (1.1% of total OTUs) in the NS samples. Statistically significant differences between the NS and the TTA samples were found for both alpha (Shannon index, observed species, Chao1 index, and Simpson index; P = 0.001) and beta (Adonis; P = 0.001) diversity. Comparison of the NS and TTA samples by farm origin and clinical signs revealed no statistical difference (P > 0.05), except for farm origin for the NS samples when compared by the unweighted UniFrac metric (P = 0.05).ConclusionsUsing 16S rRNA gene sequencing, we characterized the microbiota of the upper and lower respiratory tracts of calves, both healthy individuals and those with clinical signs of respiratory disease. Our results suggest that environmental factors may influence the composition of the upper airway microbiota in cattle. While the two microbial communities (upper and lower airways) differed in microbial composition, they shared several OTUs, suggesting that the lung microbiota may be a self-sustaining, more homogeneous ecosystem, influenced by the upper respiratory tract microbiota.

Validation of Thromboelastometry in Cattle

Thromboelastometry (TEM) and thromboelastography are useful tools for the evaluation of the entire clotting process from the activation of plasmatic factors until fibrinolysis. TEM has been validated in several domestic species but not in cattle. In this study, we defined normal TEM values in adult cattle and in veal calves; we then compared rates of coagulation in these two groups. Furthermore, the precision of the instruments was evaluated. Finally, we studied the correlation between the hematological and TEM results. In calves, we identified a faster activation of plasmatic factors (shorter clotting times) and lower fibrinogenemia. The precision of TEM on the bovine blood samples was good. Additionally, hematocrit was positively linked to clotting time of the intrinsic and extrinsic pathways, whereas fibrinogenemia was strongly associated with fib-TEM® tracing.

Ten years of BSE surveillance in Italy: neuropathological findings in clinically suspected cases.

Between 2001 and 2010, 244 clinically suspected cases of bovine spongiform encephalopathy (BSE) were reported in Italy. This report summarizes the neuropathological findings in cattle displaying clinical signs consistent with a diagnosis of BSE. All animal specimens were submitted for confirmatory testing; samples testing negative underwent neuropathological examination to establish the differential diagnosis. Immunohistochemistry for scrapie prion protein (PrPSc) at the level of frontal cortex was carried out to exclude atypical BSE. Neuropathological changes were detected in 34.9% of cases; no histological lesions were found in 52.3% of subjects; 12.8% of samples were found unsuitable for analysis. BSE was detected in one case, but no cases of atypical BSE were observed. This study identified the diseases most commonly encountered in the differential diagnosis of BSE; furthermore, it demonstrated that the surveillance system is necessary for monitoring neuropathological disease in cattle and for the detection of BSE cases.

Clinical, pathological, and molecular features of classical and L-type atypical-BSE in goats

Monitoring of small ruminants for transmissible spongiform encephalopathies (TSEs) has recently become more relevant after two natural scrapie suspected cases of goats were found to be positive for classical BSE (C-BSE). C-BSE probably established itself in this species unrecognized, undermining disease control measures. This opens the possibility that TSEs in goats may remain an animal source for human prion diseases. Currently, there are no data regarding the natural presence of the atypical BSE in caprines. Here we report that C-BSE and L-type atypical BSE (L-BSE) isolates from bovine species are intracerebrally transmissible to goats, with a 100% attack rate and a significantly shorter incubation period and survival time after C-BSE than after L-BSE experimental infection, suggesting a lower species barrier for classical agentin goat. All animals showed nearly the same clinical features of disease characterized by skin lesions, including broken hair and alopecia, and abnormal mental status. Histology and immunohistochemistry showed several differences between C-BSE and L-BSE infection, allowing discrimination between the two different strains. The lymphoreticular involvement we observed in the C-BSE positive goats argues in favour of a peripheral distribution of PrPSc similar to classical scrapie. Western blot and other currently approved screening tests detected both strains in the goats and were able to classify negative control animals. These data demonstrate that active surveillance of small ruminants, as applied to fallen stock and/or healthy slaughter populations in European countries, is able to correctly identify and classify classical and L-BSE and ultimately protect public health.

Characterization of Amyloid-β Deposits in Bovine Brains

Amyloid-β (Aβ) deposits are seen in aged individuals of many mammalian species that possess the same aminoacid sequence as humans. This study describes Aβ deposition in 102 clinically characterized cattle brains from animals aged 0 to 20 years. Extracellular and intracellular Aβ deposition was detected with 4G8 antibody in the cortex, hippocampus, and cerebellum. X-34 staining failed to stain Aβ deposits, indicating the non β-pleated nature of these deposits. Western blot analysis and surface-enhanced laser desorption/ionization time-of-flight (SELDI-TOF) mass spectrometry revealed in Tris, Triton, and formic acid fractions the presence of different Aβ peptides, characterized mainly by C-terminally truncated forms. Exploration of the genetic variability of APOE, PSEN1, and PSEN2 genes involved in Alzheimer’s disease pathogenesis revealed several previously unreported polymorphisms. This study demonstrates certain similarities between Aβ deposition patterns exhibited in cattle brains and those in the human brain in early stages of aging. Furthermore, the identification of the same Aβ peptides reported in humans, but unable to form aggregates, supports the hypothesis that cattle may be protected against amyloid plaque formation.