Short communication: Association between udder health status and blood serum proteins in dairy cows.

The aim of this study was to investigate the association between udder health (UH) status and blood serum proteins (i.e., total protein, albumin, globulin, and albumin-to-globulin ratio) in dairy cows. Blood and milk samples were collected from 1,508 cows of 6 different breeds (Holstein Friesian, Brown Swiss, Jersey, Simmental, Rendena, and Alpine Grey) that were housed in 41 multibreed herds. Bacteriological analysis was performed on milk samples with somatic cell count (SCC) >100,000 cells/mL and bacteria identification was confirmed by multiplex-PCR assays. Milk samples were grouped into 7 clusters of UH status: healthy (cows with milk SCC <100,000 cells/mL and not cultured); culture-negative samples with low, medium, or high SCC; and culture-positive samples with contagious, environmental, and opportunistic intramammary infections. Data of blood serum proteins were analyzed using a linear mixed model that included the fixed effects of stage of lactation, parity, breed, herd productivity (high or low production) and UH status, and the random effect of herd-date within herd productivity. Culture-negative samples with high milk SCC, which were most likely undergoing a strong inflammatory response and whose pathogens could not be isolated because they were engulfed by macrophages or because they had already cleared, and milk samples infected by contagious and environmental bacteria were associated with greater globulin concentrations (and lower albumin-to-globulin ratio) in blood. Variation in blood serum proteins seems to be associated with inflammatory status rather than infection, as serum globulin significantly increased in UH status groups with the highest milk SCC and no differences were observed among intramammary infections pathogens. Blood serum proteins can be a mammary gland inflammation indicator, but cannot be used to differentiate among different UH status groups.

Associations between pathogen-specific cases of subclinical mastitis and milk yield, quality, protein composition, and cheese-making traits in dairy cows.

The aim of this study was to investigate associations between pathogen-specific cases of subclinical mastitis and milk yield, quality, protein composition, and cheese-making traits. Forty-one multibreed herds were selected for the study, and composite milk samples were collected from 1,508 cows belonging to 3 specialized dairy breeds (Holstein Friesian, Brown Swiss, and Jersey) and 3 dual-purpose breeds of Alpine origin (Simmental, Rendena, and Grey Alpine). Milk composition [i.e., fat, protein, casein, lactose, pH, urea, and somatic cell count (SCC)] was analyzed, and separation of protein fractions was performed by reversed-phase high performance liquid chromatography. Eleven coagulation traits were measured: 5 traditional milk coagulation properties [time from rennet addition to milk gelation (RCT, min), curd-firming rate as the time to a curd firmness (CF) of 20 mm (k20, min), and CF at 30, 45, and 60 min from rennet addition (a30, a45, and a60, mm)], and 6 new curd firming and syneresis traits [potential asymptotical CF at an infinite time (CFP, mm), curd-firming instant rate constant (kCF, % × min-1), curd syneresis instant rate constant (kSR, % × min-1), modeled RCT (RCTeq, min), maximum CF value (CFmax, mm), and time at CFmax (tmax, min)]. We also measured 3 cheese yield traits, expressing the weights of total fresh curd (%CYCURD), dry matter (%CYSOLIDS), and water (%CYWATER) in the curd as percentages of the weight of the processed milk, and 4 nutrient recovery traits (RECPROTEIN, RECFAT, RECSOLIDS, and RECENERGY), representing the percentage ratio between each nutrient in the curd and milk. Milk samples with SCC > 100,000 cells/mL were subjected to bacteriological examination. All samples were divided into 7 clusters of udder health (UH) status: healthy (cows with milk SCC < 100,000 cells/mL and uncultured); culture-negative samples with low, medium, or high SCC; and culture-positive samples divided into contagious, environmental, and opportunistic intramammary infection (IMI). Data were analyzed using a linear mixed model. Significant variations in the casein to protein ratio and lactose content were observed in all culture-positive samples and in culture-negative samples with medium to high SCC compared to normal milk. No differences were observed among contagious, environmental, and opportunistic pathogens, suggesting an effect of inflammation rather than infection. The greatest impairment in milk quantity and composition, clotting ability, and cheese production was observed in the 2 UH status groups with the highest milk SCC (i.e., contagious IMI and culture-negative samples with high SCC), revealing a discrepancy between the bacteriological results and inflammatory status, and thus confirming the importance of SCC as an indicator of udder health and milk quality.

Lethal septic shock after dental scaling in a healthy dog due to Ochrobactrum anthropi-contaminated propofol.

A 10-year-old, 6-kg male Yorkshire terrier dog was scheduled for routine dental cleaning. No significant problem was observed either during anaesthesia, which was induced with propofol, or during recovery. However, 2 hours after discharge, the dog's owner returned to the clinic, complaining that the animal was lethargic and had had bloody diarrhoea. On physical examination the dog was depressed, dyspnoeic, tachycardic and hypoglycaemic. Despite supportive treatment, the dog deteriorated and died within a few hours.A presumed diagnosis of sepsis was confirmed by laboratory testing. Bacteriological and molecular examinations of both premortem blood samples and the anaesthetic, highlighted the presence of Ochrobactrum anthropi, an opportunistic pathogen usually associated with immunocompromised hosts with indwelling medical devices. To the authors' knowledge, this is the first case of sepsis in a healthy dog due to contamination of an anaesthetic solution by O. anthropi, suggesting a potential role of this microorganism as an emerging pathogen.

Study on ticks and tick-borne zoonoses in public parks in Italy.

A survey on tick density and on tick-borne zoonoses was carried out in four public parks in the outskirts of Imola (northern Italy) from June to October 2006. All stages of Ixodes ricinus and only larvae of Riphicephalus sanguineus were recovered by dragging, performed on 100-m transects. Almost all ticks (99%) were harvested in one park. I. ricinus density (nymphs/100 m(2) ) ranged from 0 in park L to 6.3 in park F. Nymphs and adults of I. ricinus were subjected to PCR for Anaplasma phagocytophilum, Bartonella spp., Borrelia burgdorferi s. l. and Rickettsia spp. The observed prevalences were 38.3% for Bartonella henselae, 5.2% for Bartonella clarridgeiae, 10.4% for B. burgdorferi s. l., 2.6% for Rickettsia helvetica and 13% for Rickettsia monacensis, respectively. No DNA of A. phagocytophilum was found. Acarological risks (AR) were calculated as probabilities of collecting at least one infected nymph per transect. The AR values calculated for the various zoonotic agents were 11.4% for R. helvetica, 27.7% for B. clarridgeiae, 49.7% for B. burgdorferi s. l., 57.2% for R. monacensis and 90.4% for B. henselae, respectively. In this study, B. clarridgeiae was for the first time identified in I. ricinus ticks.

Serological survey for influenza type A viruses in domestic dogs (Canis lupus familiaris) and cats (Felis catus) in north-eastern Italy.

To ascertain the potential transmission of influenza A viruses to dogs and cats, a serological survey was carried out in North-eastern Italy. In a 4-year period, 637 serum samples were screened using a Mab-based competitive ELISA for anti-nucleoprotein A (NPA) antibody detection of influenza viruses. No evidence of anti-NPA antibodies was observed.

Evaluation of the specificity of the gamma-interferon test in Italian bovine tuberculosis-free herds.

We investigated the specificity of the gamma-interferon test for bovine tuberculosis (TB) in 1,557 cattle in 30 paratuberculosis-free and officially certified TB-free dairy herds, located in three provinces of the Lombardy Region in Northern Italy. The TB-free status of the herds under examination was further confirmed by the tuberculin skin test, by an antibody assay and by post mortem examination of animals culled from the herds during the study period. The specificity of the gamma-interferon tests after a single test and a double sampling scheme were 88.8% and 95.4%, respectively. After a single test, 11.7% of dubious reactors were also detected, while most cattle (47.4%) were shown to be avian reactors, probably due to contamination from infected birds and/or forage. There was strong evidence that the specificity of the test could be related to the animals' interaction with environmental mycobacteria and/or ageing. To reduce the percentage of nonspecific bovine reactors under alleged TB-free conditions, test procedures might involve the use of more specific antigens and/or different reaction thresholds.