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In this study, we investigated associations among subclinical intra-mammary infection (IMI) and quarter-level milk composition, udder health indicators, and cheesemaking traits. The dataset included records from 450 Holstein cows belonging to three dairy herds. After an initial screening (T0) to identify animals infected by Streptococcus agalactiae , Streptococcus uberis , Staphylococcus aureus , and Prototheca spp., 613 quarter milk samples for 2 different sampling times (T1 and T2, 1 mo after T1) were used for analysis. Milk traits were analyzed using a hierarchical linear mixed model including the effects of days in milk, parity and herd, and bacteriological and inflammatory category [culture negative with somatic cell count (SCC) <200,000 cells/mL; culture negative with SCC ≥200,000 cells/mL; or culture positive]. All udder health indicators were associated with increased SCC and IMI at both sampling times. The largest effects were detected at T2 for milk lactose (−7% and −5%) and milk conductivity (+9% and +8%). In contrast, the increase in differential SCC (DSCC) in samples with elevated SCC was larger at T1 (+17%). Culture-negative samples with SCC ≥200,000 cells/mL had the highest SCC and greatest numbers of polymorphonuclear-neutrophils-lymphocytes and macrophages at both T1 and T2. Regarding milk cheesemaking ability, samples with elevated SCC showed the worst pattern of curd firmness at T1 and T2. At T2, increased SCC and IMI induced large decreases in recoveries of nutrients into the curd, in particular recovered protein (−14% and −16%) and recovered fat (−12% and −14%). Different behaviors were observed between Strep. agalactiae and Prototheca spp., especially at T2. In particular, samples that were positive for Strep. agalactiae had higher proportions of DSCC (+19%) compared with negative samples with low SCC, whereas samples that were positive for Prototheca spp. had lower DSCC (−11%). Intramammary infection with Prototheca spp. increased milk pH compared with culture-negative samples (+3%) and negative samples that had increased SCC (+2%). The greatest impairment in curd firmness at 30 min from rennet addition was observed for samples that were positive for Prototheca spp. (−99% compared with negative samples, and −98% compared with negative samples with high SCC). These results suggest that IMI caused by Prototheca spp. have detrimental effects on milk technological traits that deserve further investigation of the mechanisms underlying animals' responses to infection. [ABSTRACT FROM AUTHOR]

Ultrasound (US) imaging has been proposed as a noninvasive tool for monitoring liver dysfunction in dairy cows. This study, carried out on 306 clinically healthy Holstein cows in the first 120 d of lactation kept in 2 herds in northern Italy, aimed at investigating the association between US imaging-derived traits, namely predicted liver triacylglycerol content (pTAG, mg/g), liver depth (LD, mm), portal vein depth (PVD, mm) and area (PVA, mm2), and body size measurements, body condition score (BCS), and milk productivity indicators. Transcutaneous US examination, milk sampling, body size measurements (withers height and heart girth), and BCS were collected once from all cows in 10 sampling batches. The body weights (BW) of a subsample of 73 cows were recorded and used together with an existing data set of BW and measures of Holstein Friesian cows (n = 399) to develop a regression equation to predict BW, which was then used to compute productivity indicators by scaling the milk production traits to predicted BW. Body size measures, BCS, milk traits, and productivity indicators were classified (low, medium, and high) in 0.75 units of standard deviation of the residuals generated from a linear model that included the effects of parity, days in milk, and sampling batch. Liver pTAG, PVA, PVD, and LD were analyzed with a sequence of linear mixed models that included the fixed effects of days in milk and parity and the random effect of sampling batch as common terms, whereas the classes of body and milk traits and the productivity indicators were included one by one. The US-related traits were found to be associated with body size measurements and BCS. Specifically, pTAG was inversely related to BCS, whereas PVD and LD increased with increasing heart girth, BCS, and predicted BW. Generally, no relevant associations were observed between the US parameters and milk production traits, including when expressed in terms of productivity. In conclusion, this study suggests that US measures of liver dimensions of clinically healthy cows are related to their size, whereas pTAG concentrations reflect body condition status, with no particular implications for milk production and productivity. Moreover, healthy cows seemed able to counteract the metabolic stress of the first 120 d of the lactation period without straining liver functionality. Finally, US imaging proved to be a promising technique to assess liver metabolic conditions. However, further studies are needed to confirm its potential as a noninvasive tool for monitoring liver conditions in healthy cows. [ABSTRACT FROM AUTHOR]

Mastitis is one of the most significant diseases in dairy cows and causes several economic losses. Somatic cell count (SCC) is often used as an indirect diagnostic tool for mastitis, especially for subclinical mastitis (SCM) where no symptoms or signs can be detected. Streptococcus agalactiae is one of the main causes of contagious mastitis, and Prototheca spp. is an alga-inducing environmental mastitis that is not always correlated with increased milk SCC. The aim of this study was to evaluate the changes in the metabolomic profile of blood in relation to subclinical intramammary infection (IMI) in dairy cows. In addition, differences resulting from the etiologic agent causing mastitis were also considered. Forty Holstein-Friesian dairy cows in mid and late lactation were enrolled in this cross-sectional design study. Based on the bacteriological examination of milk, the animals were divided into 3 groups: group CTR (control group; n = 16), group A (affected by SCM with IMI caused by Strep. agalactiae ; n = 17), and group P (affected by SCM with IMI caused by Prototheca spp.; n = 7). Blood samples from the jugular vein were collected in tubes containing clot activator; the serum aliquot was stored until metabolomic analysis by 1H-nuclear magnetic resonance spectroscopy. Statistical analysis was conducted by fitting a linear model with the group as the fixed effect and SCC as the covariate. Forty-two metabolites were identified, and among them 10 were significantly different among groups. Groups A and P showed greater levels of His and lactose and lower levels of acetate, Asn, and dimethylamine compared with group CTR. Group A showed high levels of Val, and group P showed high levels of Cit and methylguanidine, as well as lower levels of 3-hydroxybutyrate, acetone, allantoin, carnitine, citrate, and ethanol. These metabolites were related to ruminal fermentations, energy metabolism, urea synthesis and metabolism, immune and inflammatory response, and mammary gland permeability. These results suggest systemic involvement with subclinical IMI and that the metabolic profile of animals with SCM undergoes changes related to the etiological agent of mastitis. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the associations between differential somatic cell count (DSCC) and milk quality and udder health traits, and for the first time, between DSCC and milk coagulation properties and cheesemaking traits in a population of 1,264 Holstein cows reared in northern Italy. Differential somatic cell count represents the combined proportions of polymorphonuclear neutrophils plus lymphocytes (PMN-LYM) in the total somatic cell count (SCC), with macrophages (MAC) making up the remaining proportion. The milk traits investigated in this study were milk yield (MY), 8 traits related to milk composition and quality (fat, protein, casein, casein index, lactose, urea, pH, and milk conductivity), 9 milk coagulation traits [3 milk coagulation properties (MCP) and 6 curd firming (CF) traits], 7 cheesemaking traits, 3 cheese yield (CY) traits, and 4 milk nutrient recovery in the curd (REC) traits. A linear mixed model was fitted to explore the associations between SCS combined with DSCC and the aforementioned milk traits. An additional model was run, which included DSCC expressed as the PMN-LYM and MAC counts, obtained by multiplying the percentage of PMN-LYM and MAC by SCC in the milk for each cow in the data set. The unfavorable association between SCS and milk quality and technological traits was confirmed. Increased DSCC was instead associated with a linear increase in MY, casein index, and lactose proportion and a linear decrease in milk fat and milk conductivity. Accordingly, DSCC was favorably associated with all MCP and CF traits (with the exception of the time needed to achieve maximum, CF), particularly with rennet coagulation time, and it always displayed linear relationships. Differential somatic cell count was also positively associated with the recovery of milk nutrients in the curd (protein, fat, and energy), which increased linearly with increasing DSCC. The PMN-LYM count was rarely associated with milk traits, even though the pattern observed confirmed the results obtained when both SCS and DSCC were included in the model. The MAC count, however, showed the opposite pattern: MY, casein index, and lactose percentage decreased and milk conductivity increased with an increasing MAC count. No significant association was found between PMN-LYM count and MCP, CF, CY, and REC traits, whereas MAC count was unfavorably associated with MCP, CF traits, some CY traits, and all REC traits. Our results showed that the combined information derived from SCS and DSCC might be useful to monitor milk quality and cheesemaking-related traits. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the International Diabetes Federation's (IDF) definition of the metabolic syndrome that independently predicts future cardiovascular events in Type 2 diabetic patients.

Abstract: Aims: We investigated if diabetes modifies the effect of the association of education with mortality and incidence of cardiovascular diseases. Methods: We identified 44,889 diabetics using multiple data sources. They were followed up from January 2002 up to December 2005, and their mortality, incidence of myocardial infarction and stroke, by educational level were analysed, and compared with those of the local non-diabetic population. Results: The all-cause Standardized Mortality Ratios among diabetics, compared with non-diabetics, were 170 for men and 175 for women. Standardized Incidence Ratios were 199 for myocardial infarction, and 183 for stroke in men and, respectively, 281, and 179 in women. Among non-diabetics there was a clear inverse relation with educational level for all outcomes, whereas among diabetics no significant social difference in incidence was found; slight social differences in mortality were present among men, but not among women. The effect of diabetes on social differences was enhanced in the youngest population. Conclusions: Diabetes increases the risk of death and the incidence of vascular diseases, but reduces their inverse association with education. This is likely related to the high accessibility and good quality of health care provided by the local networks of diabetic centres and primary care. [Copyright &y& Elsevier]

Aims To estimate the prevalence of cardiovascular disease (CVD) in Type 2 diabetic patients with and without non-alcoholic fatty liver disease (NAFLD), and to assess whether NAFLD is independently related to prevalent CVD. Methods We studied 400 Type 2 diabetic patients with NAFLD and 400 diabetic patients without NAFLD who were matched for age and sex. Main outcome measures were prevalent CVD (as ascertained by medical history, physical examination, electrocardiogram and echo-Doppler scanning of carotid and lower limb arteries), NAFLD (by ultrasonography) and presence of the metabolic syndrome (MetS) as defined by the World Health Organization or Adult Treatment Panel III criteria. Results The prevalences of coronary (23.0 vs. 15.5%), cerebrovascular (17.2 vs. 10.2%) and peripheral (12.8 vs. 7.0%) vascular disease were significantly increased in those with NAFLD as compared with those without NAFLD ( P < 0.001), with no differences between sexes. The MetS (by any criteria) and all its individual components were more frequent in NAFLD patients ( P < 0.001). In logistic regression analysis, male sex, age, smoking history and MetS were independently related to prevalent CVD, whereas NAFLD was not. Conclusions The prevalence of CVD is increased in patients with Type 2 diabetes and NAFLD in association with an increased prevalence of MetS as compared with diabetic patients without NAFLD. Follow-up studies are necessary to determine whether this higher prevalence of CVD among diabetic patients with NAFLD affects long-term mortality. Diabet. Med. (2006) [ABSTRACT FROM AUTHOR]

AIMS: To estimate the prevalence of cardiovascular disease (CVD) in Type 2 diabetic patients with and without non-alcoholic fatty liver disease (NAFLD), and to assess whether NAFLD is independently related to prevalent CVD. METHODS: We studied 400 Type 2 diabetic patients with NAFLD and 400 diabetic patients without NAFLD who were matched for age and sex. Main outcome measures were prevalent CVD (as ascertained by medical history, physical examination, electrocardiogram and echo-Doppler scanning of carotid and lower limb arteries), NAFLD (by ultrasonography) and presence of the metabolic syndrome (MetS) as defined by the World Health Organization or Adult Treatment Panel III criteria. RESULTS: The prevalences of coronary (23.0 vs. 15.5%), cerebrovascular (17.2 vs. 10.2%) and peripheral (12.8 vs. 7.0%) vascular disease were significantly increased in those with NAFLD as compared with those without NAFLD (P < 0.001), with no differences between sexes. The MetS (by any criteria) and all its individual components were more frequent in NAFLD patients (P < 0.001). In logistic regression analysis, male sex, age, smoking history and MetS were independently related to prevalent CVD, whereas NAFLD was not. CONCLUSIONS: The prevalence of CVD is increased in patients with Type 2 diabetes and NAFLD in association with an increased prevalence of MetS as compared with diabetic patients without NAFLD. Follow-up studies are necessary to determine whether this higher prevalence of CVD among diabetic patients with NAFLD affects long-term mortality. [ABSTRACT FROM AUTHOR]