Effect of a Probiotic Mixture in Captive Cheetahs (Acinonyx Jubatus) with Gastrointestinal Symptoms—A Pilot Study

Simple Summary

In recent years, many studies have demonstrated the effectiveness of probiotics in acute and chronic gastrointestinal disorders in both humans and animals. The objective of this study is to evaluate the effect of a specific probiotic mixture in cheetahs. In the wild, cheetah populations have drastically reduced due to habitat destruction, human–wildlife conflict and illegal wildlife trade. In captivity, chronic gastrointestinal diseases have a high prevalence. Based on our results, it can be concluded that probiotics may be helpful as a dietary supplement in cheetahs suffering from gastrointestinal disease.

Abstract

Cheetahs (Acinonyx jubatus) are classified as “vulnerable” species due to the low numbers persisting in the wild. Gastrointestinal diseases are very common in this species when they are kept in captivity, in particular gastritis. Clinical signs are predominantly characterized by vomiting, diarrhea, weight loss and anorexia. In this study, we evaluated the efficacy of a multi-strain probiotic in two groups of cheetahs: Group A (n = 4)—rescued cheetahs housed at the Cheetah Conservation Fund (Otjiwarongo, Namibia); Group B (n = 9)—captive cheetahs housed in Italian zoos. Animals showed gastrointestinal signs of different severity, and were positive for Helicobacter spp., detected by PCR in stool samples. Two sachets of probiotic formulation were administered to all cheetahs once a day for 21 consecutive days. Clinical conditions (appetite loss, vomiting, stool consistency and Body Condition Score) before (T0) and after 21 days of probiotic administration (T1) were then compared using a simplified Feline Chronic Enteropathy Activity Index (FCEAI) score. A slight but not significant improvement in the scores was observed in Group A, which had mild intestinal symptoms, while a significant decrease in vomiting and stool consistency (**p < 0.01) scores was observed in Group B, which had more pronounced symptoms. Results suggest that high concentrations of live probiotics can be of help in managing gastrointestinal signs in cheetahs.

The untargeted lipidomic profile of quarter milk from dairy cows with subclinical intramammary infection by non-aureus staphylococci

This observational study determined the lipidome of cow milk during subclinical intramammary infection (IMI) by non-aureus staphylococci (NAS), also defined as coagulase-negative staphylococci, using an untargeted approach. Among the pathogens causing bovine IMI, NAS have become the most frequently isolated bacteria from milk samples. Although the application of system biology approaches to mastitis has provided pivotal information by investigating the transcriptome, proteome, peptidome, and metabolome, the milk lipidome during mammary gland inflammation remains undisclosed. To cover this gap, we determined the milk lipidome of 17 dairy cows with IMI caused by NAS (NAS-IMI), and we compared the results with those of healthy quarter milk from 11 cows. The lipidome was determined following a liquid chromatography-quadrupole time-of-flight mass spectrometry approach. Sixteen subclasses of lipids were identified in both groups of animals. From 2,556 measured lipids, the abundance of 597 changed more than 10-fold in quarter milk with NAS-IMI compared with healthy quarters. The results demonstrate the influence of NAS-IMI on the milk lipidome, implying significant changes in lipid species belonging to the family of triacylglycerols and sphingomyelins, and contribute to the understanding of inflammatory processes in the bovine udder, highlighting potential novel biomarkers for improving mastitis diagnostics.

Different distribution of antimicrobial resistance genes and virulence profiles of Staphylococcus aureus strains isolated from clinical mastitis in six countries

Staphylococcus aureus is recognized worldwide as one of the main contagious mastitis agents in cattle and can express a set of antimicrobial resistance genes and virulence-associated genes that explain the wide range of outcomes of intramammary infections. Staphylococcus aureus strains are heterogeneous: their different resistance and virulence patterns, associated with host-level factors and treatment factors, are related to the severity of infection. The aim of this study was to determine phenotypic antibiotic susceptibility, occurrence of selected antimicrobial resistance genes and other virulence genes in 93 S. aureus strains isolated from clinical mastitis in 6 countries: Argentina, Brazil, Germany, Italy, the United States (New York State), and South Africa. These isolates were tested against a total of 16 drugs (amoxicillin-clavulanate, ampicillin, cefazolin, cefoperazone, cefquinome, enrofloxacin, erythromycin, gentamicin, kanamycin, lincomycin, oxacillin, penicillin, rifampin, spiramycin, sulfamethoxazole/trimethoprim, tylosin) by minimum inhibitory concentration (MIC) assay, and examined for the presence of 6 antibiotic-resistance genes (blaZ, mecA, mecC, ermA, ermB, ermC) and 6 virulence-associated genes (scn, chp, sak, hla, hlb, sea) via PCR analysis. The phenotypic results of this study revealed the presence of 19.4% penicillin-resistant strains, whereas 22.6% of the strains were classified as having resistance (5.4%) or intermediate resistance (17.2%) to erythromycin. Most (96.8%) of the isolates were inhibited by cephalosporins, and all were susceptible to amoxicillin-clavulanate. Two strains (1 from Germany, 1 from Italy) were resistant to oxacillin and were positive for mecA. Among the other antimicrobial resistance genes, the most frequently detected was blaZ (46.2%), and 32.3% of the isolates were positive for erm genes: ermC (21.5%) and ermB (10.8%). The most prevalent virulence gene was hla (100%), followed by hlb (84.9%) and sea (65.6%). These results show a low prevalence of antibiotic multidrug resistance in S. aureus isolates, even if the detection of selected antimicrobial resistance genes did not always correspond with the occurrence of phenotypic antibiotic resistance; the immune evasion cluster gene prevalence was quite low in the samples analyzed.

Detecting the Hidden Properties of Immunological Data and Predicting the Mortality Risks of Infectious Syndromes

BACKGROUND

To extract more information, the properties of infectious disease data, including hidden relationships, could be considered. Here, blood leukocyte data were explored to elucidate whether hidden information, if uncovered, could forecast mortality.

METHODS

Three sets of individuals (n = 132) were investigated, from whom blood leukocyte profiles and microbial tests were conducted (i) cross-sectional analyses performed at admission (before bacteriological tests were completed) from two groups of hospital patients, randomly selected at different time periods, who met septic criteria [confirmed infection and at least three systemic inflammatory response syndrome (SIRS) criteria] but lacked chronic conditions (study I, n = 36; and study II, n = 69); (ii) a similar group, tested over 3 days (n = 7); and (iii) non-infected, SIRS-negative individuals, tested once (n = 20). The data were analyzed by (i) a method that creates complex data combinations, which, based on graphic patterns, partitions the data into subsets and (ii) an approach that does not partition the data. Admission data from SIRS+/infection+ patients were related to 30-day, in-hospital mortality.

RESULTS

The non-partitioning approach was not informative: in both study I and study II, the leukocyte data intervals of non-survivors and survivors overlapped. In contrast, the combinatorial method distinguished two subsets that, later, showed twofold (or larger) differences in mortality. While the two subsets did not differ in gender, age, microbial species, or antimicrobial resistance, they revealed different immune profiles. Non-infected, SIRS-negative individuals did not express the high-mortality profile. Longitudinal data from septic patients displayed the pattern associated with the highest mortality within the first 24 h post-admission. Suggesting inflammation coexisted with immunosuppression, one high-mortality sub-subset displayed high neutrophil/lymphocyte ratio values and low lymphocyte percents. A second high-mortality subset showed monocyte-mediated deficiencies. Numerous within- and between-subset comparisons revealed statistically significantly different immune profiles.

CONCLUSION

While the analysis of non-partitioned data can result in information loss, complex (combinatorial) data structures can uncover hidden patterns, which guide data partitioning into subsets that differ in mortality rates and immune profiles. Such information can facilitate diagnostics, monitoring of disease dynamics, and evaluation of subset-specific, patient-specific therapies.

Genomic characteristics of Staphylococcus aureus strains associated with high within-herd prevalence of intramammary infections in dairy cows

Staphylococcus aureus is one of the most important causes of mastitis in dairy cattle. Based on previous research, Staph. aureus genotypes with different pathogenic and contagious properties can cause intramammary infection (IMI) and coexist in the same herd. Our study aimed to compare Staph. aureus strains from herds that differed in IMI prevalence using different molecular approaches such as ribosomal spacer (RS)-PCR, multilocus sequence typing (MLST), spa typing, ribotyping, pulsed-field gel electrophoresis (PFGE), and multiplex PCR. For this purpose, 31 dairy herds with Staph. aureus IMI were selected, and 16 of these were chosen for a comparison study: the 8 high-prevalence (HP) herds had Staph. aureus IMI prevalence >28% and the 8 low-prevalence (LP) herds had an IMI prevalence <4%. A total of 650 isolates of Staph. aureus from mammary quarters of all positive cows were genotyped with RS-PCR, a technique based on amplification of a portion of the intergenic spacer 16S-23S rRNA, and a subset of 54 strains was also analyzed by multiplex PCR, ribotyping, PFGE, MLST, and spa typing. The RS-PCR analysis revealed 12 different profiles. Staphylococcus aureus strains isolated from 5 out of 8 HP herds showed a profile identical to the genotype B (GTB), described in previous studies as being strongly associated with high within-herd prevalence of Staph. aureus mastitis and the presence of the genes coding for enterotoxins sea, sed, and sej, a long x-region of spa gene, and 3 lukE fragments. Moreover, all strains isolated in the HP herds possessed genes coding for staphylococcal enterotoxins. In LP herds, a limited number of strains of 6 genotypes, different from those isolated in HP herds, were identified and GTB was not found. Within these genotypes, 4 strains were positive for the mecA gene. Preliminary results and comparison with other genotyping methods confirmed that genotyping by RS-PCR is an accurate, rapid, and inexpensive tool for future field studies on Staph. aureus mastitis strains and generates clinically relevant results.

Methicillin-resistant Staphylococcus aureus (MRSA) is associated with low within-herd prevalence of intra-mammary infections in dairy cows: Genotyping of isolates

Staphylococcus aureus is one of the most common mastitis-causing pathogens worldwide. In the last decade, livestock-associated methicillin-resistant S. aureus (LA-MRSA) infections have been described in several species, included the bovines. Hence, this paper investigates the diffusion of MRSA within Italian dairy herds; the strains were further characterized using a DNA microarray, which detects 330 different sequences, including the methicillin-resistance genes mecA and mecC and SCCmec typing. The analysis of overall patterns allows the assignment to Clonal Complexes (CC). Overall 163 S. aureus isolates, collected from quarter milk samples in 61 herds, were tested. MRSA strains were further processed using spa typing. Fifteen strains (9.2%), isolated in 9 herds (14.75%), carried mecA, but none harboured mecC. MRSA detection was significantly associated (P<0.011) with a within-herd prevalence of S. aureus intra-mammary infections (IMI) ≤5%. Ten MRSA strains were assigned to CC398, the remaining ones to CC97 (n=2), CC1 (n=2) or CC8 (n=1). In 3 herds, MRSA and MSSA co-existed: CC97-MRSA with CC398-MSSA, CC1-MRSA with CC8-MSSA and CC398-MRSA with CC126-MSSA. The results of spa typing showed an overall similar profile of the strains belonging to the same CC: t127-CC1, t1730-CC97, t899 in 8 out of 10 CC398. In the remaining 2 isolates a new spa type, t14644, was identified. The single CC8 was a t3092. The SCCmec cassettes were classified as type IV, type V or type IV/V composite. All or most strains harboured the genes encoding the β-lactamase operon and the tetracycline resistance. Streptogramin resistance gene was related to CC398. Enterotoxin and leukocidin genes were carried only by CC1, CC8 and CC97-MRSA. The persistence of MRSA clones characterized by broader host range, in epidemiologically unrelated areas and in dairy herds with low prevalence of S. aureus IMI, might enhance the risk for adaptation to human species.

Outbreak of bovine clinical mastitis caused by Mycoplasma bovis in a North Italian herd

This report describes an outbreak of Mycoplasma bovis mastitis affecting 45 cows in a herd of 122 dairy cattle in Northern Italy. Clinically, the outbreak was characterized by agalactia, multiple swollen and painless quarters, high milk somatic cell count and unresponsiveness to conventional antibiotic therapy. M. bovis was isolated from the milk samples of all the 32 affected cows tested and from the mammary tissue of three affected cows that underwent necropsy. No other pathogens were isolated from these samples. Lesions in two of the necropsied cows were characterized by mild chronic suppurative mastitis and galactophoritis. The other necropsied cow showed a chronic necrosuppurative and pyogranulamaous galactophoritis, a condition not previously associated with M. bovis. M. bovis was detected immunohistochemically in the lumen of the affected mammary ducts suggesting that ascending infection via the teat canal was the likely route of transmission. No other intralesional pathogens were demonstrated microscopically.

Mycobacterium genavenseand avian polyomavirus co-infection in a European Goldfinch (Carduelis carduelis)

Systemic mycobacteriosis associated with avian polyomavirus infection was diagnosed histologically in an 8-year-old, captive European goldfinch with a history of nervous signs. Severe mycobacterial lesions were observed in the central nervous system, lungs, cervical air sacs and adrenal glands, without involvement of the gastrointestinal tract. In addition to mycobacteriosis, intranuclear inclusions, typical of polyomavirus, were identified in the adrenal glands. Polymerase chain reaction assays were used to identify Mycobacterium genavense and finch polyomavirus as the causative agents. The absence of involvement of the gastrointestinal tract and the severity of the lesions in the respiratory tract suggested that inhalation may have been the primary route of infection with M. genavense.

Cough sound description in relation to respiratory diseases in dairy calves

Cough can be a biomarker in case of respiratory diseases. By monitoring and analyzing cough sounds through automatic devices, the farmer can obtain an early warning about a developing outbreak of respiratory infections. Cough sounds can be characterized by particular acoustic features (amplitude, frequency and duration) that are obtained by sound recording, labeling and analytic procedures. Based on these features, it might be possible to develop an automated cough recognition system. The aim of the study described in this paper is to investigate whether it is possible to discriminate cough sounds from other frequently occurring sounds in youngstock stables. Nasal swabs and blood were taken to identify the microbiological agents responsible for the respiratory problems. The collected cough sounds were compared to metal rack sounds, which are very common sounds in cattle farming, to identify acoustic differences between them. Results show that the length of cough sounds was significantly different from metal rack sounds (0.34 versus 0.37 s, P<0.05). Also, the analysis of amplitude and fundamental frequency showed significant differences between both types of sounds (resp. 0.21 and 0.18; 1326 and 3868 HZ). This indicates that it is possible discriminate cough sounds from other sounds and that cough sound can be used as a non-invasively diagnostic tool for respiratory diseases in youngstock groups.

[Crystalline silica can induce oxidative stress by inhibiting glyoxalase system in bronchial epithelial cells]

Chronic inflammation and reactive oxygen species (ROS) production induced by crystalline silica are involved in the development of silicosis and lung cancer pathogenesis. ROS can generate lipid peroxydation of cell membranes that can produce methylglyoxal (MG), a strong cell proliferation inhibitor and apoptosis inducer. MG is naturally removed by glyoxalase I (GI) and glyoxalase II (GII) through a glutathione (GSH) dependent mechanism. Therefore mRNA expression of glyoxalases is correlated to MG concentration and oxidative stress.

OBJECTIVES

evaluate oxidative stress induced by crystalline silica by glyoxalases mRNA expression and methylglyoxal concentration

MATERIAL AND METHODS

In bronchial epithelial cell culture (BEAS-2B), exposed to 50 microg/cm2 crystalline silica (Min-U-Sil 5), for 2, 6, 12, and 24 hours, GI and GII mRNA levels and MG intracellular concentration were measured respectively by Real-Time PCR and HPLC.

RESULTS

Crystalline silica exposure induced a significant reduction in mRNA expression of glyoxalases and an increase of MG intracellular concentration.

CONCLUSIONS

The results suggest a possible use of MG and mRNA expression of GI and GII as crystalline silica induced oxidative stress indicators.

[Urinary 1-naphthol in the general population of Umbria]

INTRODUCTION

Naphthalene, the most volatile polycyclic aromatic hydrocarbon (PAH), was recently classified as possible human carcinogen by International Agencies for Research on Cancer Humans may be exposed to naphthalene from a wide variety of sources, including occupation, environment, personal habits. We assessed urinary excretion of 1-naphthol (1-NAF), biomarker of naphthalene exposure, in non-occupationally exposed subjects.

MATERIALS AND METHODS

Urinary 1-NAF, 1-hydroxypyrene (1-OHP), biomarker of exposure to pyrene and cotinine, biomarker of smoking habits, were measured in 104 adults (53 men, 51 women).

RESULTS

1-NAF concentrations overlapped in males and females (median: men 0.35 Microg/g creat; women: 0.46 microg/g creat). Median concentration of 1-NAF was 6-fold higher in smokers compared to nonsmokers (respectively, 7.7 microg/g creatinine vs 1.3 microg/g creatinine). Between smokers, urinary cotinine was positively correlated to 1-naphthol (rho: 0.69; p < 0.01) and 1-OHP (rho: 0.53; p < 0.01). Higher 1-OHP concentrations were found in smokers (median: smokers 0.16 microg/g creatinine, not-smokers 0.05 microg/g creatinine;).

CONCLUSIONS

In our study population, we found that 1-NAF excretion is much higher as compared to 1-OHP excretion. This is due to the ubiquitous presence of naphthalene in the environment. Smoking considerably increase the exposure to naftalene.

Comparison of Blood Non-Specific Immune Parameters in Bovine Virus Diarrhoea Virus (BVDV) Persistently Infected and in Immune Heifers

Several data from different authors show that Bovine virus diarrhoea virus (BVDV) could be a key component in multiple-etiology diseases, indeed a lower leukocytes number and their impaired functions decrease the resistance to infections. However, most of the information on the impairment of immune function during BVDV infections arise from circumstantial evidence and from experimental infection studies, and few from field data. To assess the effects of BVDV on blood cells parameters, cellular and humoral functions under field conditions, we designed a controlled study in commercial dairy herds, comparing persistent infected (PI) and healthy heifers. A total of 45 heifers were considered, the PI animals were nine, the control animals were 34, while two controls were considered as acute infected animals. The comparison of the mean values in PI calves showed a significant decrease for leukocytes and granulocytes, while platelets showed a significant increase, when compared with control animals. The total number of lymphocytes decreased not significantly in PI animals, while the proportion significantly increased. The number and proportion of monocytes was significantly reduced in PI animals, when compared with controls. The data collected on markers of cellular immunity during our study cannot be compared with the literature because there are no reference values. The presence of a persistent infection affected the cellular enzymes: NAGase, lysozyme and respiratory burst showed a large statistically significant decrease in PI animals when compared with controls. The presence of a persistent infection with BVD virus influenced blood cells number and impaired some blood cell functions. Such impairment confirms that PI animals represent a threat to the herd not only because they could spread BVDV, but also because they are more susceptible to other infectious diseases.

Field Study on Protocols for Evaluation of Teat Skin Conditions

Different protocols to evaluate teat skin status under field conditions based on scoring and on the measurement of pH and hydration of teat skin were evaluated. After determination of the teat score for all eligible animals in a commercial dairy herd, 50 of them were chosen, based on their pre-trial average teat score, and separated in two groups. Two different post-dipping products with the same amount of disinfectant, but with a different concentration of emollient were applied. All four teats were assessed with the corneometer and pH probes. A digital picture of each teat skin and teat orifice was taken with a digital camera. Hydration and pH data were analysed by anova with repeated-measurement factors, while teat skin and apex score patterns, were assessed by the means of Mann-Whitney test; between- and within-group changes were assessed by the mean of Mantel-Haenzel chi-square statistic. Data showed that teat skin pH and hydration could be assessed under field conditions and they were influenced by teat conditioning. The approach based on evaluating odds for scores, stratified for sampling and for treatment, was found to be a sensitive and informative way to compare the changes between and within treatment groups.

Epidemiological Study of Non-contagious Intramammary Infections in Nine Commercial Dairy Herds following a Staphylococcus aureus Control Programme

Changes in prevalence in intramammary infection, by pathogen type, in herds applying a stringent contagious mastitis control programme was studied. Enrollment of 1651 lactating cows and collection of milk samples was made in this ancillary study to a cohort study of the dynamics of mastitis prevalence after adoption of a strict contagious mastitis control programme that targeted the elimination of mastitis caused by Staphylococcus aureus. Nine commercial dairies in Italy were used. Aseptic collection of milk samples from all lactating cows was performed at the time of enrollment, from all cows within 7-14 days of entering the lactating herd after the date of enrollment, and from all lactating cows at 2, 4, 7, 10 and 14 months after the date of enrollment. Prevalence of intramammary infection by pathogen type was determined from culture of milk samples. Application of the strict contagious mastitis programme did not lead to an increased risk of non-contagious mastitis. The risk of coliform, environmental streptococcal and coagulase-negative staphylococcal intramammary infections decreased after adoption of the programme. The data reported herein indicate that the overall risk for any intramammary infections decreases with adoption of a strict contagious mastitis programme, and that such a programme therefore does not necessarily lead to an increase in environmental mastitis.

Primary DNA damage in chrome-plating workers

In order to evaluate the primary DNA damage due to occupational exposure to chromium (VI), DNA strand-breaks and apoptosis in peripheral lymphocytes were measured in a group of 19 chrome-plating workers. DNA strand-breaks was assessed by alkaline (pH>13) single-cell microgel electrophoresis ('comet') assay, while apoptosis was measured by flow-cytometry after propidium iodide staining of the cells. Concentrations of chromium in urine, erythrocytes and lymphocytes were investigated as biological indicators of exposure. A group of 18 hospital workers (control group I) and another 20 university personnel (control group II) without exposure to chromium were also studied as controls. The results of the study show that chrome-plating workers have higher levels of chromium in urine, erythrocytes and lymphocytes than unexposed workers. Comet tail moment values, assumed as index of DNA damage, are increased in chromium-exposed workers and results are significantly correlated to chromium lymphocyte concentrations. No difference emerged in the percentage of apoptotic nuclei in exposed and unexposed workers. The study confirms that measurements of chromium in erythrocytes and lymphocytes may provide useful information about recent and past exposure to hexavalent chromium at the workplace. The increase in DNA strand-breaks measured by comet assay suggests this test is valid for the biological monitoring of workers exposed to genotoxic compounds such as chromium (VI).

Relationship among plasmids recovered from Staphylococcus aureus, milk leukocytes, and antimicrobial resistance

The efficacy and efficiency of mastitis control schemes in reducing the incidence of Staphylococcus aureus mastitis could be improved if the different strains of Staph. aureus were characterized by their pathogenicity. Plasmid finger printing of Staph. aureus strains could be a rather simple and efficient method to characterize the strains and their interaction with host cellular immune defenses. The aim of this study was to investigate the presence and distribution of plasmids in strains of Staph. aureus isolated from bovine mastitis and their relationship with mammary gland immune defenses and antimicrobial resistance. Overall, nine different plasmids were identified by their molecular weight. One or more plasmids were isolated from 293 strains (96.4%), and only 11 strains did not show the presence of any plasmid. A significant difference in polymorphonuclear neutrophil proportions was observed in association with 23-kb, 9416-bp, 2027-bp, or 1353-bp plasmids, and for macrophage proportions, significant differences were observed for 9416-bp, 6557-bp, or 1353-bp plasmids. Penicillin G minimum inhibitory concentration values showed significant differences when 6557-bp, 4361-bp, 2322-bp, or 2027-bp plasmids were present, and weak or no differences were observed for cephacetrile, rifamycin, and norfloxacin. The presence of 2027-bp plasmid was associated with a reduced neutrophil response and an increased resistance against beta-lactam antimicrobials; therefore, the strains carrying this plasmid have a higher probability to invade and colonize mammary gland, to survive to antimicrobial therapy, and to remain undetected. Results confirmed that plasmid fingerprinting is a simple and effective way to characterize Staph. aureus strains.

Relationship between teat tissue immune defences and intramammary infections

The teat is the main entrance for pathogens into the mammary gland. It also acts as a sensory, motor and primary defence organ. This latter function is important in preventing intramammary infections while efficiency in preventing new infections is determined by teat tissue integrity. Machine milking may evoke mechanical and circulatory impairment in teat tissues. These local metabolic disorders may decrease the efficiency of the local immune defence mechanisms. Teat tissue changes can be estimated by measuring teat thickness before and after milking. Experimental and field studies showed a high correlation between changes in thickness and infection risk. Teats with > 5% change in thickness have significantly increased teat duct colonisation rates and intramammary infection rates. The link between changes in teat thickness and infections should be found in changes in local immune defences and measurable changes in cytological and biochemical immune factors are expected. Indeed, the application of experimental milking conditions (i.e. no pulsation milking and positive pressure milking) showed to have a significant influence on some non specific immune factors in teat secretion. Positive pressure milking increases PMNs content and decreases macrophages content of teat secretion. Some enzymes such as NAGase and lysozyme were decreased by positive pressure milking, the concentration of the same enzymes were higher after no pulsation milking. A better knowledge on the interaction between the teat apex immune defense mechanisms and the machine milking process is necessary to reduce the new infection rate of the bovine mammary gland.

Study on the relationship between milk immune factors and Staphylococcus aureus intramammary infections in dairy cows

The distribution of Staphylococcus aureus within herds seems to be related to interactions among the shedding characteristics of the bacteria, their pathogenicity and mammary gland immune status. The aim of the present study was to investigate the relationships between selected mammary gland immune factors and intramammary infections associated with Staph. aureus. Overall, 70 cows from five commercial dairy herds were included in the study and quarter milk samples were assessed using bacteriological and cytological tests. We evaluated differential cell count, lysozyme concentration, N-acetyl-beta-glucosaminidase (NAGase) activity, cell viability and respiratory burst activity in randomly chosen quarter milk samples from each cow. Staph. aureus intramammary infection elicited different responses in the mammary gland immune defences investigated. Polymorphonuclear leucocytes (PMN) as a proportion of total somatic cells in milk, cell viability and NAGase activity were higher in infected quarters, while the proportions of macrophages and lymphocytes, respiratory burst activity and lysozyme levels were lower. Mean values differed among herds, but the differences were not significant. These changes were associated with Staph. aureus infection. The reduced respiratory burst activity together with the increase in the proportion of PMN suggests that both the number and activity of PMN could influence the susceptibility of the mammary gland to pathogens. Indeed, the logistic model adopted suggests that impairment of milk immune factors could be concurrent with the development of an infection.

Efficacy of a biological response modifier in preventing Staphylococcus aureus intramammary infections after calving

A change in the epidemiology of mastitis in recent years has emphasized the role of the udder immune system in the pathogenesis of Staphylococcus aureus. Therefore, if the bovine or udder immune capability could be enhanced, susceptibility to Staph. aureus could be reduced and antibiotic efficacy could be increased. Immune system defense mechanisms could be enhanced by vaccination and by biological response modifiers. Within this latter group, a biological response modifier obtained from Parapox ovis that was attenuated over 200 tissue culture passages was recently developed and commercialized in some European countries. This study reports the results of a field trial on the efficacy of this biological response modifier in reducing Staph. aureus intramammary infection (IMI) after calving in primiparous and pluriparous cows. The trial included 106 cows sampled six times (55 cows from herd A and 51 from herd B) for a total of 2544 quarter milk samples. The analysis of IMI prevalence showed that 25.09% of samples were bacteriologically positive in the placebo group, and 23.17% of the positive samples were observed in the biological response modifier group. Staphylococcus aureus IMI had a frequency of 11.44% in the placebo group and 6.00% in the biological response modifier group. The dynamic of the hazards showed significantly lower rates in the biological response modifier group than in the placebo group (risk ratio = 0.47). Treatment with the parapox-containing biological response modifier showed significant reduction of Staph. aureus IMI around calving, and this reduction was attributed to an increase in immune defenses.

Blood cadmium concentrations in the general population of Umbria, central Italy

The aims of this study were (a) to assess blood cadmium (B-Cd) concentrations and to establish a tentative reference interval; (b) to identify significant determinants of B-Cd, in a population from Umbria, Central Italy, which was not occupationally exposed to cadmium (Cd). Four hundred and thirty-four healthy blood-donors volunteered to answer a questionnaire and provide a blood sample for B-Cd analysis, which was performed by graphite furnace atomic absorption spectrophotometry. Blood Cd concentrations ranged from non-detectable values, i.e. below 0.1 microgram/l up to 3.4 micrograms/l and were not normally distributed. The median values and the 95th percentiles were 0.7 and 2.0 micrograms/l, respectively. Concentrations of B-Cd were more than double in smokers than in non-smokers, median values being 1.1 micrograms/l and 0.5 microgram/l, respectively. In current smokers, B-Cd values correlated with the number of cigarettes smoked daily (rs = 0.40, P = 0.0001) and with the cumulative exposure to cigarette smoke (rs = 0.35, P = 0.0001). Concentrations of B-Cd correlated with age in the non-smokers, but not in the smokers and were significantly higher in women than in men only in the non-smokers. Both in smokers and non-smokers, B-Cd concentrations were similar in subjects living in urban or in rural areas. In the whole study population the lower and the upper tentative reference limit were < 0.1 and 2.2 micrograms/l, respectively, as computed by a non-parametric rank-based method. The upper limit was approximately double in smokers than in non-smokers (3.1 micrograms/l and 1.6 micrograms/l, respectively). Our results show that B-Cd concentrations in a general population from Umbria are in the range reported for general populations in Northern Italy and other European Countries. Smoking was the strongest determinant of B-Cd concentrations and age had a lesser effect.

Study on prevalence of bovine viral diarrhoea virus (BVDV) antibodies in 29 Italian dairy herds with reproductive problems

An epidemiological survey on prevalence distribution of antibodies to BVDV was carried out in dairy cattle herds during 1995-1996 in northern Italy. A total of 704 serum samples from 29 non-vaccinated herds reported to have reproductive problems were tested for serum neutralising antibodies. In each herd, sampling was based on the stratification by age into five classes (< 6 months old calves, 6-12 months old calves, pregnant heifers, uniparous, pluriparous). Overall, 53.3% of samples were serologically positive, with the lowest ratio in 6-12 months old calves (37.9%) and the highest in pluriparous cows (71.2%).

[Lead absorption in an Umbrian population from 1982 to 1992]

This report assessed lead absorption in community samples of the general population in Umbria, central Italy, in 1982 and in 1992. Each participant (128 subjects in 1982 and 479 in 1992) answered a questionnaire providing details of personal information and life style. Blood lead levels were determined by atomic absorption spectrophotometry. In 1992 hematocrit and glutamyltranspeptidase (gamma-GT) levels were also measured. In 1982 the mean blood lead level was 226 micrograms/l in males and 167 micrograms/l in females, and in 1992 it was still higher in males than in females (98 micrograms/l vs 61 micrograms/l) as were hematocrit and gamma-GT levels. Multiple regression analysis showed sex and age were the main factors accounting for 42% of the total variation in blood lead levels. They were followed by alcohol consumption, gamma-GT levels and smoking in this order. In conclusion, blood lead levels decreased significantly in central Italy in the decade 1982-92 and persistent lead absorption seems to be due to individual characteristics such as male sex, advanced age and a personal life style which includes alcohol consumption and smoking.

Recovery of Staphylococcus aureus from centrifuged quarter milk samples

The identification of cows that are positive for mastitis caused by Staphylococcus aureus is difficult under field conditions. The frequency of isolation of S. aureus from quarter milk samples was compared with the frequency of recovery of S. aureus from sediment after centrifugation of those same samples. Overall, 776 quarter milk samples from 194 cows were studied. Cultures that were positive for S. aureus were obtained from 82 samples; 153 sediments from quarter milk samples were also positive for S. aureus. The results of this investigation showed that cultures of the sediment of quarter milk samples increased the number of positive outcomes up to 145.5%, depending on the herd. Using a different group of samples, including samples taken 1 to 5 d or 7 to 10 d after calving and samples taken after intramammary therapy, a 94% increase in cultures that were positive for S. aureus after centrifugation was found compared with cultures of the same quarter milk samples that were not centrifuged. Sedimented cultures may be useful in S. aureus control programs that require the segregation, selective treatment, or culling of cows that are positive for S. aureus.

Reference values of urinary chromium in Italy

OBJECTIVES

The paper describes the results of a polycentric study for the assessment of reference values of urinary chromium (U-Cr) in the Italian population.

METHOD

A total of 890 subjects (58.3% males and 41.7% females) were selected on the basis of standardized criteria in eight different areas of Italy. Urinary chromium was determined on morning spot samples collected using standardized procedures. The U-Cr was determined independently by three laboratories using an Electrothermic atomization-Atomic Absorption Spectrometry (ETA-AAS) method with a detection limit of 0.05 microgram/l, adopting-for the statistical analysis-the median value of the results of the three laboratories. The between-laboratories within-subjects standard deviation was 0.049 microgram/l. Due to the high proportion (approx, 28%) of undetectable chromium levels, the geometric mean (GM) and geometric standard deviation (GSD) were estimated using a procedure of linear interpolation. The analysis of the effects of some variables (sex, age, center, residence, smoking and drinking habits) on the U-Cr values, was also performed, by multiple regression analysis after logarithmic transformation, using GM and SD.

RESULTS

The reference value of U-Cr was of 0.08 microgram/l as an estimated GM, whereas the expected distribution ranged from not detectable (nd) (95% CI = nd-0.06) to 0.24 microgram/l (95th percentile; 95% CI = 0.20-0.31). Among the variables studied, only geographical area and sex significantly influenced the U-Cr levels. In subjects selected in the provinces of Bari and Venice values of U-Cr were significantly lower than those determined in subjects residing in other areas.

CONCLUSIONS

From our investigation the reference values for U-Cr were lower than those obtained in previous investigations. In addition it confirms a further reduction in U-Cr levels following the previous decline reported in the 1970s and 1980s. In over 20 years U-Cr values in the general population dropped from values greater than 1 microgram/l to values between 0.5 and 0.2 microgram/l. The reasons of this progressive decline cannot be attributed in our opinion to a reduced intake of the metal, but mainly to the improvement in analytical instrumentation and methods. A further decrease may be ascribed to a more accurate definition of the reference groups and to a better control of pre-analytical factors. Considering that the reference values for U-Cr are much lower than those determined some decades ago, toxicological studies in order to verify the significance of biological limit values currently suggested for chromium seem to be necessary.

Field study on the relationship between teat thickness changes and intramammary infections

The aim of this study was to describe the results of teat thickness measurement applied routinely in three commercial dairy herds and to evaluate the influence of machine-induced teat thickness changes on intramammary infection and the frequency of new infection. A total of 1018 fore milk samples and the same number of teat apex measurements have been evaluated. Overall, relative teat thickness changes were normally distributed (mean -0.16%, SD 10.15%), while a specific pattern could be observed within herds. Increases in teat thickness of > 5% were significantly associated with infection and new infection (odds ratio > 1), but the association was not significant when teat thickness decreased by more than 5%. When results were classified according to aetiology, analysis showed that coagulase-negative staphylococcal infections were significantly associated with both increases and decreases in teat thickness numerically greater than 5%.

Effects of desferrioxamine therapy on chronic disease anemia associated with rheumatoid arthritis

OBJECTIVE

To investigate the effects of desferrioxamine (DFO) infusion on chronic disease anemia (CDA) of rheumatoid arthritis (RA) by evaluating interleukin-6 (IL-6) and erythropoietin (EPO) production.

PATIENTS AND METHODS

Five patients with RA and CDA (group I) were treated with DFO, 500 mg daily, through a continuous 10-h subcutaneous infusion 5 days a week for 4 weeks. One month after withdrawal, DFO was resumed in all five group I patients (group II) with an increase to 1 g daily following the previous treatment schedule. Clinical and laboratory parameters were evaluated weekly during the two study periods. Serum EPO was measured by radioimmunoassay. IL-6 was detected by the enzyme-linked immunoabsorbent assay method.

RESULTS

No significant variations in hematological parameters, IL-6 or EPO levels were observed in group I patients. After 1 week of DFO 1 g daily, reticulocyte counts and EPO improved significantly. Hemoglobin and hematocrit rose significantly after 3 weeks of 1 g daily DFO therapy. Four weeks after DFO withdrawal, EPO, reticulocyte counts, hemoglobin and hematocrit returned to baseline levels. A significant improvement in the clinical parameters of disease activity was observed, particularly in group II patients.

CONCLUSION

DFO improves CDA in RA patients. The beneficial effects on erythropoiesis seem to be related to improved EPO responsiveness to the anemia.

Effect of inhaled nedocromil sodium therapy on blood gas changes in children challenged with ultrasonically nebulized distilled water. A comparison of 8 mg versus 16 mg daily dose

Changes in time course of blood partial pressures of oxygen (PtcO2) and carbon dioxide (PtcCO2) before, during and after challenge with ultrasonically nebulized distilled water (UNDW) were evaluated in 22 children with mild asthma in basal conditions, and after 8 weeks of therapy with inhaled nedocromil sodium at a daily dosage of 8 or 16 mg. PtcO2 and PtcCO2 were followed using transcutaneous O2 and CO2 monitoring system. All asthmatic subjects presented a significant decrease in PtcO2 and/or PtcCO2 (> 20% basal value) during or after challenge. After therapy, the decrease in PtcO2 and PtcCO2 was normalized in the group treated with 16 mg/day, whereas only a partial yet significant reduction in the decrease of O2 and CO2 was observed in the group assuming 8 mg/-day. These data indicate that inhaled nedocromil is effective in treating bronchial hyperresponsiveness in childhood and that the dose required to achieve this effect is of 16 mg/day.

Exposure to cobalt in the welding process with stellite

In some small factories producing moulds for ceramic tiles using a cobalt alloy (stellite), environmental and biological (CoU) monitoring was conducted for eight workers employed in gas-shielded arc (MAG) and oxy-acetylene welding processes. During oxy-acetylene braze-welding, the exposure to cobalt is very low as are urinary cobalt concentrations. On the other hand, during the MAG welding process, the exposure levels can exceed the TLV-TWA levels and correlated well with CoU at the end of a working shift. Two MAG welders followed for two consecutive weeks, showed different patterns of urinary cobalt excretion: under the same environmental conditions, the higher CoU was found in the worker with greater past exposure. This aspect needs further evaluation before adopting CoU as a current indicator of occupational exposure to the metal.

Cobalt powdersintering industry (stone cutting diamond wheels): a study of environmental-biological monitoring, workplace improvement and health surveillance

This communication deals with an aspect of occupational hygiene in a factory producing granite cutting diamond wheels by sintering, in moulds, of fine cobalt powder. The factory has been studied between 1988 and 1991; the Department of Preventive and Occupational Medicine of the Local Sanitary Unit of Reggio Emilia has followed the evolution of the local exhaust ventilation equipment supplied by the employer in that period. At the same time, the following measurements and observations were carried out: (a) cobalt exposure by personal sampling, (b) airborne cobalt measurements by area sampling, (c) biological monitoring of cobalt in urine, (d) health surveillance.

Phagocytic activity of bovine polymorphonuclear neutrophil leucocytes

Two different investigations were conducted on the chemiluminescent activity of bovine milk polymorphonuclear neutrophil leucocytes (PMN) activated by different stimuli: zymosan, derived from the wall of Saccharomyces cerevisiae (Experiment A), and Streptococcus uberis and Escherichia coli (Experiment B). In Experiment A, a quarter with a phagocytic activity of PMN < 20 mV/1000 PMN following stimulation with zymosan was found to be 23 times more likely to be a clinical mastitis case than a quarter with phagocytic activity above this threshold value. In Experiment B, calculation of the odds ratio showed similar results following stimulation with Str. uberis or Esch. coli. These results provide evidence that immunocompromisation of mammary gland defences could predispose to clinical mastitis. They also support the need to challenge phagocytic cells with appropriate stimuli, and the Esch. coli test seems to be the most sensitive.

[Influence of alcohol on the behavior of dose and effect indicators in workers exposed to inorganic lead: unexpected behavior of ZPP]

A study was carried out on 65 male workers heavily exposed to lead in the ceramic tile manufacturing industry in order to assess the effects of alcohol on the biological indicators of lead (PbB, ALA-D, ALA-U, ZPP). All subjects selected for the study had PbB levels greater than or equal to 60 micrograms/dl, normal levels of serum iron and no haemoglobin disorders. The subjects were divided into three groups according to alcohol intake checked by anamnestic investigation, mean corpuscular volume (MCV) values and liver function parameters, as follows: Group A--27 subjects, controls, with daily alcohol intake less than 80 ml, MCV less than or equal to 95 mu 3, normal GGT, AST and ALT levels; Group B--20 subjects, heavy drinkers, with daily alcohol intake greater than or equal to 80 ml, MCV greater than 95 mu 3, occasionally high GGT, but normal AST and ALT values; Group C--18 subjects, heavy drinkers, with daily alcohol intake greater than or equal to 80 ml, MCV greater than 95 mu 3, abnormal GGT, AST and ALT levels. The length of lead exposure did not significantly differ in the three groups. The well-known effects of ethanol intake on PbB, ALA-D and ALA-U values were confirmed, with the following mean values in the three groups: Group A: PbB = 66.0 (micrograms/dl), ALA-D = 10.3 (mU/ml r.c.), ALA-U = 8.4 (mg/l); Group B: PbB = 68.3 (micrograms/dl), ALA-D = 6.7 (mU/ml r.c.), ALA-U = 9.1 (mg/l); Group C: PbB = 71.5 (micrograms/dl), ALA-D = 4.6 (mU/ml r.c.), ALA-U = 12.7 (mg/l).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood and hair lead levels in 6-year old children according to their parents' occupation

Some authors found higher lead levels in children whose parents are occupationally exposed to the metal, which is probably carried home with dirty work clothes. In order to verify the relevance of the risk in tile-workers' children we examined 3 groups of 5-7 years old children whose parents were: a) tile workers employed in lead areas; b) tile workers not employed in lead areas; c) workers not occupationally exposed to lead (control group). We found that lead workers children had PbB and PbH significantly higher than control children although all PbB values were lower than 30 micrograms/dl. Nevertheless this observation suggests that major attention must be paid to individual preventive measures, such as the change of work clothes and good personal hygiene after every work shift.