Sensor technology to support herd health monitoring: Using rumination duration and activity measures as unspecific variables for the early detection of dairy cows with health deviations.

A significant number of lactating dairy cows are affected by health disorders in the early postpartum period. Precision dairy farming technologies have tremendous potential to support farmers in detecting disordered cows before clinical manifestation of a disease. The objective of this study was to evaluate if activity and rumination measures obtained by a commercial 3D-accelerometer system, i.e. "lying", "high active", "inactive", and "rumination" times, can be used for early identification of cows with health deviations before the clinical manifestation of disease. A total of 312 Holstein cows equipped with an ear attached accelerometer (Smartbow GmbH, Weibern, Austria) were monitored and analyzed from 14 days prior to parturition to eight days in milk (DIM). Animals were checked daily for clinical disorders from zero to eight DIM using standard operating procedures and by blood ß-hydroxybutyrate measurements at three, five, and eight DIM. Cows that presented no symptoms of health problems and with BHB concentrations <1.2 mmol/L in the first eight DIM were classified as healthy (n = 156) and used as the reference in this study. Cows with disorders were allocated in groups with one disorder (n = 65) and >1 disorders (n = 91). "Rumination" durations per day were already shorter five days before the clinical diagnosis (D0) in diseased cows (401.9 ± 147.4 min/day) compared with healthy controls (434.6 ± 140.3 min/day). "Rumination" time decreased before the diagnosis, with a nadir at Day -1 for healthy cows and cows with >1 disorder (392.0 ± 147.9 vs. 313.4 ± 162.6 min/day). Cows with one disorder reached a nadir on Day -3 (388.8 ± 158.6 min/day). Similarly, the "high active" time started to become shorter three days before the clinical diagnosis in diseased cows compared to healthy cows (164.1 ± 119.1 vs. 200.3 ± 111.5 min/day). The times cows spent "inactive" were significantly longer three days before clinical diagnosis in diseased cows compared to healthy cows (421.7 ± 168.3 vs. 362.8 ± 117.6 min/day). "Lying" time started to become significantly longer one day before the diagnosis of disorders in disordered cows compared to healthy cows (691.8 ± 183.3 vs. 627.3 ± 158.0 min/day). On average, these results indicated a strong disturbance of physiological parameters before the clinical onset of disease. In summary, it was possible to show differences between disordered and healthy cows based on activity and "rumination" data recorded by a 3D-accelerometer.

Supplementing rumen-protected methionine to lactating multiparous dairy cows did not improve reproductive performance.

There is evidence that supplementing methionine has positive effects on uterine environment, oocyte quality and embryo development in cattle. Thus, the objective of this study was to evaluate reproductive traits of cows supplemented with rumen-protected methionine (RPM) during early to mid-lactation in comparison with an untreated control group (CON). An additional focus was on the effect of puerperal diseases on reproductive performance parameters in RPM-supplemented group MET and in CON. A total of 1,709 multiparous Holstein-Friesian cows were enrolled in this field trial conducted on a commercial dairy farm in Slovakia. Cows were allocated at approximately 12 days post-partum (dpp) to either CON or MET, the latter supplemented with 25.0 g-27.2 g RPM per cow per day incorporated into the total mixed ration (TMR) until leaving the study pen at approximately 140 dpp. The amount of RPM was calculated based on individual feed ingredients analysis and adjusted during the study period when TMR changed. Cows were monitored during the post-partum period by vaginal examination (day 5 pp), measuring of beta-hydroxybutyrate in blood (3, 5, and 8 dpp) and by vaginal examination, uterine cytology and measuring of back fat thickness by ultrasound (all at 31 ± 3 dpp). Compared with CON, cows supplemented with RPM did not show better reproduction performance parameters (first service submission rate, days to first service, conception risk, days open 140). Results from binary logistic regression model for the risk of conception showed that metritis had a significant effect, but the supplementation of methionine had not. Results of Cox regression analysis for the odds of conception within 140 dpp revealed only metritis and clinical endometritis as significant factors. In conclusion, supplementation of RPM had no beneficial effect on reproductive performance in this study farm compared with an untreated control group.

Tumor necrosis factor receptor 2-dependent homeostasis of regulatory T cells as a player in TNF-induced experimental metastasis.

The cytokine tumor necrosis factor (TNF) has pleiotropic functions both in normal physiology and disease. TNF signals by the virtue of two cell surface receptors, TNF receptor 1 (TNFR1) and TNF receptor 2 (TNFR2). Exogenous TNF promotes experimental metastasis in some models, yet the underlying mechanisms are poorly understood. To study the contribution of host TNFR1 and TNFR2 on tumor cell progression and metastasis, we employed a syngeneic B16F10 melanoma mouse model of lung metastasis combined with in vivo bioluminescence imaging. Treatment of tumor-bearing mice with recombinant human TNF resulted in a significant increase in tumor burden and metastatic foci. This correlated with an increase in pulmonary regulatory CD4(+)/Foxp3(+) T cells. TNF caused an expansion of regulatory T (Treg) cells in vitro in a TNFR2-dependent manner. To assess the contribution of immune cell expression of endogenous TNF and its two receptors on B16F10 metastasis, we generated bone marrow chimeras by reconstituting wild-type mice with bone marrow from different knockout mice. Loss of either TNF or TNFR2 on immune cells resulted in decreased B16F10 metastasis and lower numbers of Treg cells within the lungs of these animals. Selective depletion of Treg cells attenuated metastasis even in conjunction with TNF treatment. We propose a novel mechanism in which TNF activates TNFR2 on Treg cells and thereby expands this immunosuppressive immune cell population. Loss of either TNF or TNFR2 prevents the accumulation of Treg cells and results in a less tolerogenic environment, enabling the immune system to control B16F10 tumor metastasis and growth.

Trapping and proteomic identification of cellular substrates of the ClpP protease in Staphylococcus aureus.

In the important human pathogen Staphylococcus aureus the cytoplasmic ClpP protease is essential for mounting cellular stress responses and for virulence. To directly identify substrates of the ClpP protease, we expressed in vivo a proteolytic inactive form of ClpP (ClpP(trap)) that will retain but not degrade substrates translocated into its proteolytic chamber. Substrates captured inside the proteolytic barrel were co-purified along with the His-tagged ClpP complex and identified by mass spectrometry. In total, approximately 70 proteins were trapped in both of the two S. aureus strains NCTC8325-4 and Newman. About one-third of the trapped proteins are previously shown to be unstable or to be substrates of ClpP in other bacteria, supporting the validity of the ClpP-TRAP. This group of proteins encompassed the transcriptional regulators CtsR and Spx, the ClpC adaptor proteins McsB and MecA, and the cell division protein FtsZ. Newly identified ClpP substrates include the global transcriptional regulators PerR and HrcA, proteins involved in DNA damage repair (RecA, UvrA, UvrB), and proteins essential for protein synthesis (RpoB and Tuf). Our study hence underscores the central role of Clp-proteolysis in a number of pathways that contribute to the success of S. aureus as a human pathogen.