Effects of herd and physiological status on variation of 16 immunological and inflammatory parameters in dairy cows during drying off and the transition period.

During drying off and transition period, cows are subject to changes in endocrine status, metabolic stressors and altered immune functions, which could lead to an increased risk of disease. To expand our knowledge on the immune/inflammatory status and to identify markers to define cow status during this interval, the pattern of 9 different cellular parameters, 5 cytokines, 2 enzymes and 3 cellular ratios in blood samples were assessed in 15 primiparous cows belonging to three different dairy herds in Lombardy. Our data showed that the variation of almost all parameters was influenced by the physiological period in which the samples were collected, except for apoptosis, IL-1ß, IL-6, lysozyme and granulocyte/monocyte ratio. Several markers were directly correlated either to the herd alone (IL-1ß, IL-6, lysozyme, granulocyte/lymphocyte ratio and granulocyte/monocyte ratio) or in association with the sampling time (white blood cell count, necrosis, lymphocytes count, CD4+ lymphocytes proportion). Hierarchical cluster analysis identified three herd-associated sample clusters showing different frequency along the follow-up period. The results of this field study highlight the importance of the herd factor in the immune/inflammatory response. Furthermore, these results suggest that cellular parameters are probably the most suitable markers to define cow status during drying-off and the peripartum period.

Total and Differential Cell Counts as a Tool to Identify Intramammary Infections in Cows after Calving.

Milk differential somatic cells count (DSCC), made possible under field conditions by the recent availability of a high-throughput milk analyzer may represent an improvement in mastitis diagnosis. While an increasing number of studies reports data on DSCC on individual cow samples, very few concerns DSCC from quarter milk samples. This paper reports for the first time the results of a retrospective study aiming to assess the performance of total (SCC), DSCC, and a novel calculated marker (PLCC) measured on quarter milk samples as a method to identify cows at risk for intramammary infection (IMI) in the first 30 days after calving. Overall, 14,586 valid quarter milk samples (3658 cows) taken in the first 30 days of lactation were considered. Quarters with major pathogens (MP) IMI, as expected, showed significantly higher means for SCC, DSCC, and PLCC. The accuracy, sensitivity, and specificity of the diagnosis based on different cut-offs calculated by ROC analysis are relatively close among DSCC, PLCC, and SCC (up to cut-off of 200,000 cells/mL). However, decision-tree analysis which includes the costs of analysis, but also the costs of the actions taken after test results showed as PLCC has the lowest cost among the three markers, and PLCC and SCC are cost effective when MP prevalence is higher than 6-10%. This diagnostic approach is of high interest particularly when selective dry cow therapy is applied to improve animal health at the herd level.

Factors Affecting the Patterns of Total Amount and Proportions of Leukocytes in Bovine Milk.

Differential leukocyte count (DSCC) in milk is considered important to improve knowledge of udder immune response. The investigations on milk DSCC were limited by the techniques available until recently, when a high-throughput tool to perform DSCC opened the way to explore these factors in rapid and economically sustainable ways. We hypothesized that DSCC alone does not fully describe the pattern of these cells, since the total amount is also influenced by milk yield and SCC. Therefore, this study was designed to describe DSCC and total amount of different leukocytes in milk during the course of lactation in cows differing in parity and in levels of SCC. This study considered 17,939 individual milk tests from 12 dairy herds in Lombardy Region, where DCC testing was applied in the period of February 2018-December 2019 (23 months). The samples were divided into two subsets-"healthy" (HS) with SCC ≤200,000 cells/mL and "inflamed" (IS) with SCC >200,000 cells/mL. Cow in HS have a P + LT average between 5.0 × 108 and 3.0 × 109 cells. In IS cows, the values were 1.6 × 1010 and 2.5 × 1010. Therefore, the presence of a well-defined inflammatory process increased the overall amount of polymorphonuclear neutrophils (PMN) and lymphocytes (LYM) of 1 log, from 1 × 109 to 1 × 1010. The assessment of the total amount of PMN and LYM, to our knowledge, have never been reported in scientific literature; the values observed may be proposed as benchmarks for studies on udder immune response. When data were analyzed by days in milk (DIM), they showed that cows in first and second lactation have a significantly lower amount of PMN + LYM, when compared to cows in third and higher lactation. However, these differences are numerically not very large (7%), and suggest that, in healthy animals, the number of immune cells is kept as constant as possible. In IS, the analysis of trends based on DIM showed that both DSCC and P + LT have a significant negative trend. These data suggest that only in this group, the presence of high SCC as lactation proceeds is associated with a progressive increase in the number of macrophages. To the best of our knowledge, this is the first study describing the pattern of DSCC and the total amount of PMN + LYM in relation to parity, days in milk, and SCC, and it may be considered as the first contribution in the investigation on mammary gland immune response by the means of differential cell counts in milk.

Differential Somatic Cell Count as a Marker for Changes of Milk Composition in Cows with Very Low Somatic Cell Count.

The recent availability of a high-throughput milk analyzer performing a partial differential somatic cell count (DSCC) opened new opportunities in investigations on bovine udder health. This analyzer has a potential limitation on the accuracy of measurements when the somatic cell count (SCC) is below 50,000 cells/mL, values characterizing a good proportion of lactating cows in many herds. We obtained data for cows below this threshold, assessed the repeatability of these measurements and investigated the relationship between DSCC and udder health, milk composition and yield. Overall, 3022 cow milk test records performed on a Fossomatic™ 7/DC (Foss A/S, Hillerød, Denmark) were considered; 901 of them had an SCC ≤ 50,000 cells/mL. These latter samples were analyzed by qPCR to identify the presence of bacteria. Overall, 20.75% of the samples (187) were positive. However, the health status did not have any significant association with DSCC. The analysis of the association of DSCC on milk fat, protein and casein showed a significant decrease in their proportions as the DSCC increased, whereas it was not observed for milk yield and lactose. Therefore, DSCC in very low SCC cows may be suggested as a marker to identify early changes in milk composition.

From "One Health" to "One Communication": The Contribution of Communication in Veterinary Medicine to Public Health.

Despite the fact that health communication is a discipline developed only recently, its importance in human medicine is well recognized. However, it is less considered in veterinary medicine, even if it has the potential to improve public health because of the role of veterinary medicine in public health. For this reason, an One Health approach is useful for communication as well. This approach leads to a "One Communication" concept, which is the result of the synergy in communicative efforts both in human and in veterinary medicine. Our analysis explores the potential of communication in several veterinary fields: institutions, food safety, companion animal and food-producing animal practice, pharmacology and drugs, wildlife fauna and environment. In almost all the areas of veterinary activity communication can contribute to human health. It takes many forms and use several channels, and this variety of communicative opportunities represent a challenge for veterinarians. For this reason, the communication course should be included in the curricula of Veterinary Medicine Schools. As One Health, One Communication is a strategy for expanding collaborations in health communication and it will enhance public health.

Listeria monocytogenes serotypes in human infections (Italy, 2000-2010).

BACKGROUND: In developed countries invasive listeriosis is an infection of great concern to public health to due its clinical severity and high fatality rate, despite its low incidence. In Europe, statistically significant increasing trends in listeriosis notification rates from 2005 to 2009 were noted in Austria, Denmark, Hungary, Italy, Spain and Sweden. MATERIALS AND METHODS: The standardized techniques based on phenotype to typing Listeria monocytogenes is the serotyping. In Europe, as elsewhere in the world, about 95% of L. monocytogenes strains isolated from clinical and food samples belongs to serovars 1/2a, 1/2b, 1/2c and 4b. RESULTS: The target of this work is to draw attention to this important and atypical foodborne disease, reporting epidemiological data and serotypes distribution of 251 human L. monocytogenes isolates reported during 2000-2010 to Veterinary Public Health and Food Safety Department of Istituto Superiore di Sanità, focusing on epidemiological trend of invasive listeriosis in Lombardia, a North Italian Region. The serotypes most frequently identified are 1/2a, 4b, 1/2b (in total 92%), but the detection of uncommon serotypes is not missing (1/2c, 3a, 3b, 4d). CONCLUSIONS: In Italy the surveillance laboratory network, as well as the foodborne disease network (ENTER-NET), has revealed in the last 11 years an increase trend of listeriosis cases reported likewise with results of Notificable National Infectious Disease surveillance System. This is probably due to a real increase of listeriosis, even if there is a greater sensitivity of the network in some regions.