[Relationship between body condition of dairy cows in the peripartum period and selected metabolic parameters in consideration of different breeds]. / Zusammenhänge zwischen Körperkondition von Milchkühen im peripartalen Zeitraum und ausgewählten Stoffwechselparametern unter Berücksichtigung verschiedener Rassen.

OBJECTIVE: The results of this study describe the relationship between the body condition of dairy cows and selected metabolic parameters during the peri- and post-partum period with special consideration of 3 local dairy cow breed in Upper Bavaria and the Allgau. MATERIAL AND METHODS: Three local dairy cattle breeds (Swiss Brown (BV), Simmental (FL), Holstein Friesian (HF)) were examined on 68 farms in southern Germany for 7 consecutive weeks. In dry cows as well as lactating cows (5.-65. day in milk), following blood parameters were investigated: beta-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA), creatinine, aspartate aminotransferase, gamma-glutamyltransferase, glutamate dehydrogenase, total protein, albumin, creatine kinase. In addition, body condition (body condition score [BCS] and back fat thickness [BFT]) were recorded. Exploratory and descriptive statistics were used for data analysis. RESULTS: Concerning the difference in condition before and after calving, the FL showed the smallest difference in RFD. For FL and BV a trend towards higher BFT values could be seen in first lactating cows. For FL and HF, the NEFA values of the later lactating cows were below those of the first lactating cows. The higher lactating cows of BV and FL had higher BHB values. The correlation between BFT and BCS showed the highest R2 (0.53) in the HF cows. BV and FL were below at 0.42 and 0.37. BCS and BFT could not be predicted by the variables NEFA, BHB and liver enzymes. BHB levels of all 3 breeds increased at weeks 2-4 post-partum. The NEFA values for all 3 breeds increased primarily in the 1st-3rd week p.p. in parallel to when the BFT p.p. decreased. NEFA values were highest when body condition declined and therefore when fat mobilization peaked. In BV and HF, there was a constant increase in GLDH when the p.p. BCS difference was there. CONCLUSION AND CLINICAL RELEVANCE: Body condition assessment (BCS at herd and animals` level, BFT at animal level) is an important tool for animal health monitoring. Due to the recognizable breed specificity, the dairy herds can be dealt with more explicitly. The aim is to optimally influence the energy balance of the cow during early lactation in order maintain the health of the animal and its organ systems.

[Use of milk haptoglobin concentration as an indicator in animal health monitoring of dairy cows]. / Nutzung der Haptoglobinkonzentration in Milch als Indikator für das Tiergesundheitsmonitoring bei Milchkühen.

OBJECTIVE: The aim of the present study was to investigate relationships between elevated haptoglobin concentrations in milk and clinical as well as laboratory parameters in early lactating dairy cows. Furthermore, cut-off values should be identified for the differentiation of healthy and affected animals. MATERIAL AND METHODS: 1462 dairy cows between 5.-65. days in milk were examined on 68 Bavarian farms. Milk and blood samples were taken once a week for a 7-week period per farm and body-condition-scoring, backfat thickness measurement and Metricheck examination, to evaluate uterine health, were performed. Milk samples were analysed for milk fat, milk protein, lactose, urea, ß-hydroxybutyrate and non-esterified fatty acids (indirect measurement, based on IR spectra), cell count, and milk haptoglobin. Blood samples were analysed for creatinine, aspartate aminotransferase, gamma-glutamyl transferase, glutamate dehydrogenase, total protein, albumin, creatine kinase, ß-hydroxybutyrate, non-esterified fatty acids, and blood haptoglobin.Cluster analyses were performed to determine cut-off values for haptoglobin. RESULTS: Besides milk haptoglobin (µg/ml) and blood haptoglobin (µg/ml), cell count (cells/ml milk), milk fat (%), milk protein (%), non-esterified fatty acids in blood (mmol/l), lactation number, days in milk, breed, season, and milk yield (kg) were included as significant input variables (p<0.005) in the cluster analyses. Cluster analysis, using k-means resp. k-prototypes algorithms, resulted in 5 (clusters 1-5 M1) resp. 4 different clusters (clusters 0-3 M2 and 0-3 B).A cut-off value of 0.5 µg/ml haptoglobin in milk was determined for the differentiation of healthy and affected animals. CONCLUSION AND CLINICAL RELEVANCE: As milk is an easily available substrate, routine determination of haptoglobin in milk might be a suitable parameter for animal health monitoring. Using the detected cut-off value, apparently healthy animals with subclinical inflammatory diseases can be identified more quickly.

Differentiating between metabolic health statuses in Simmental cows and describing related milk fatty acids and relevant associated factors.

The aim of this observational study was to examine differences in milk fatty acid (FA) concentrations for different metabolic health statuses and for associated factors-specifically to examine with which FA concentrations an increased risk for developing a poor metabolic adaptation syndrome (PMAS) was associated. During weekly visits over 51 wk, blood samples were collected from cows between 5 and 50 days in milk. The farmer collected corresponding milk samples from all voluntary milkings. The analysis was performed on n = 2,432 samples from n = 553 Simmental cows. The observations were assigned to five different cow types (healthy, clever, athletic, hyperketonemic, and PMAS, representing five metabolic health statuses), based on the thresholds of 0.7 mmol/L, 1.2 mmol/L, and 1.4 for the concentrations of ß-hydroxybutyrate and nonesterified fatty acids and for the milk fat-to-protein ratio, respectively. Linear regression models using the predictor variables cow type, parity, week of lactation, and milk yield as fixed effects were developed using a stepwise forward selection to test for significant associations of predictor variables regarding FA concentrations in milk. There was a significant interaction term found between PMAS cows and parity compared to healthy cows for C18:1 (P < 0.001) and for C18:0 (P < 0.01). It revealed higher concentrations for PMAS in primiparous and multiparous cows compared to healthy cows, the slope being steeper for primiparous cows. Further, an interaction term was found between PMAS cows and milk yield compared to healthy cows and milk yield for C16:0 (P < 0.05), revealing a steeper slope for the decrease of C16:0 concentrations with increasing milk yield for PMAS compared to healthy cows. The significant associations and interaction terms between cow type, parity, week of lactation, and milk yield as predictor variables and C16:0, C18:0, and C18:1 concentrations suggest excellent opportunities for cow herd health screening during the early postpartum period.

[Use of serum haptoglobin concentration as an indicator in animal health monitoring of dairy cows]. / Nutzung der Haptoglobinkonzentration im Blutserum als Indikator im Tiergesundheitsmonitoring bei Milchkühen.

OBJECTIVE: To investigate the association between haptoglobin concentration in the blood and the occurrence of ketosis, selected clinical parameters as well as lameness in dairy cows. MATERIAL AND METHODS: The data was collected on 39 dairy farms in Bavaria over a period of 8 months. In 712 Simmental and Brown Swiss cows, clinical examinations as well as milk and blood samplings were performed between 10 and 30 days after calving. In these blood samples, the concentrations of non-esterified fatty acids (NEFA), ß-hydroxybutyric acid (BHBA) and haptoglobin (Hp) were determined. Analysis of the milk included milk constituents (fat, protein, urea, lactose and acetone), BHBA, NEFA and the somatic cell count (SCC). RESULTS: Significant correlations were found between increased Hp-concentration on the one hand and increased NEFA levels in blood and milk (p < 0.001), increased somatic cell count (p < 0.001), lameness (p < 0.001), as well as reduced lactose content (p < 0.001) and protein content in the milk (p = 0.001) on the other hand. Animals sampled during the warmer summer months showed significantly higher serum Hp-concentrations (p < 0,001). Heifers exhibited significantly higher Hp-values than multiparous individuals (p < 0.001). By dividing the examined cows into 4 clusters, a Hp-threshold value could be determined at 0.18 mg/ml. Combined with a SCC threshold of 40 500 cells/ml milk, the majority of animals with subclinical and clinical abnormalities could be identified. CONCLUSION AND CLINICAL RELEVANCE: Measurement of the Hp-concentration in blood is a pertinent approach in animal health monitoring during the postpartum period. In combination with evaluations of milk amount and contents, deviations from the physiological status may be recognized and affected individuals treated early on. Haptoglobin may be used to assess the health status of the individual animal as well as an indicator of herd health in the context of animal health monitoring.