[Development and basics of metabolic monitoring in dairy cows. Focus on research in Eastern Germany and at the University of Leipzig, Germany]. / Entwicklung und Grundlagen der Stoffwechselüberwachung bei Milchkühen. Darstellung mit Schwerpunkt auf der Forschung in Ostdeutschland und an der Universität Leipzig.

UNLABELLED: Systematic metabolic monitoring began in German-speaking countries in the late 1960s, early 1970s, due to an increase in metabolic disorders as a cause of infertility and mastitis and aimed at their prevention through early diagnosis. Development of a unified monitoring standard: Initiated by Rossow, Gürtler, Ehrentraut, Seidel and Furcht a standard "metabolic monitoring in cattle production" was developed in the 1970s. It included farm analysis, clinical and biochemical controls, prophylaxis and follow-up controls. Key points were: periodic screenings of heavily loaded, healthy indicator animals 2-4 days post partum (p.  p.), 2-8 weeks p.  p. and 1-2 weeks ante partum, maximal 10 animals/group, pooled samples are useful, optimal are individual samples, use of informative sample substrate and parameters, precise handling of specimens, expert assessment and follow-up. Metabolic controls during 1982-1989 in approximately 242  000 cows revealed means of 32.9% ketoses, 20.0% metabolic acidosis, 21.9% metabolic alkalosis, 34.2% nitrogen-metabolism disorders, 17.3% sodium deficiency and 23.7% liver disorders. Development of a metabolic profile after 1989: Reference values at higher milk yield, early diagnosis of diseases of the fat mobilization syndrome and improved early diagnosis by new indicators, including creatine kinase (CK), alkaline phosphatase (AP) with isoenzymes, acute phase proteins, cytokines, antioxidants, carnitine and lipoprotein fractions, were established. Optimized blood and urine screenings have important advantages over milk analysis. They are an important method of health and performance stabilization by exact analysis of causes and derived prevention. CLINICAL RELEVANCE: The fertility related parameters free fatty acids, ß-hydroxybutyrate, urea, inorganic phosphate, CK, AP, sodium, potassium, selenium, copper, ß-carotene and net acid-base excretion proved to be a standard spectrum for screenings. These should be tested once a year/herd, if necessary as an inexpensive pool sample for approximately 50 €.

[Metabolic monitoring on small and medium sized dairy farms in Emsland, Germany]. / Stoffwechselmonitoring in kleinen und mittelgroßen Milchrindbetrieben im Emsland.

OBJECTIVE: The aim of this study was to evaluate metabolic analyses on small dairy farms regarding indications, realization, and results over 5 years. MATERIAL AND METHODS: In 793 serum samples (122 submissions from 53 farms) originating from cows of different lactation stages and from heifers, the parameters free fatty acids (FFA), ß-hydroxybutyrate (BHB), cholesterol, urea, creatinine, glucose, total protein, albumin, bilirubin, liver enzymes, creatine kinase (CK), ß-carotene, electrolytes and trace elements were analyzed. RESULTS: In 20% of cases, investigations were initiated to control for the metabolic status. Further reasons for laboratory diagnostics were consistent with the culling causes. FFA with 56.7% displayed the most frequent deviations from the normal range during the lactation ante partum. At 8 weeks post partum (p. p.) it fell to 36-38% and later to < 11%. The BHB deviations from the normal range exceeded 68% throughout the whole lactation. During the middle and late lactation, 40-50% of the measured urea concentrations were above the upper reference limit. Hypocalcemia occurred during the first week p. p. to 13.2% and hypophosphatemia to 6.6%. For CK, deviations from the reference value of 60.4-90.0% were determined. Selenium and copper deficiencies were present in approximately 15% of cases. Heifers more frequently displayed a copper deficiency (21.3%) than cows. ß-carotene deficiency was measured ante partum at 50% and p. p. at 47.1-77.8%. Adverse deviations increased between 2006 and 2011 for FFS, urea, ß-carotene, and selenium in correlation with a reduction in the milk price between 2009 and 2010. Deviations from the normal range for BHB, CK, cholesterol, calcium, and inorganic phosphate remained constant. On 80% of the farms, the metabolic status improved during the investigation period. CONCLUSION: Even on smaller farms, peripartal metabolic screenings enable early discovery of causes of the most common culling reasons and provide options for corrective action.

[Behavior of antioxidant parameters in young cattle during the course of the year]. / Verhalten antioxidativer Parameter bei Jungrindern im Jahresverlauf.

OBJECTIVE: To analyze the behavior of antioxidant parameters in young cattle over 1 year and to detect possible health-related deficits during certain periods. MATERIALS AND METHODS: Every 2 months over the course of 1 year, six healthy 12-month-old Holstein Friesian/German black and white heifers underwent a clinical examination and blood samples were obtained. The 36 animals were kept in tie-stalls during September, November, January, March and July, and solely at pasture in May. The antioxidant parameters superoxide dismutase (SOD), glutathione peroxidase (GPX) and the Trolox equivalent antioxidant capacity (TEAC), hematocrit and the metabolic parameters ß-hydroxybutyrate, bilirubin, cholesterol, protein, albumin, urea, haptoglobin, calcium, inorganic phosphate, iron, alkaline phosphatase, aspartate transaminase, glutamate dehydrogenase and creatine kinase were determined. RESULTS: The GPX activities in September and January were significantly lower than those from March till July. The TEAC concentrations were in particular lower in January and significantly lower in March than in September and November. Differing SOD activities were not statistically significant. The correlation between SOD and GPX during the entire period was significant as well as between SOD and TEAC throughout the year except in January, whereas GPX and the TEAC only significantly correlated in November and from March till July. Albumin significantly correlated with the TEAC. The metabolic parameters were within the physiological range at all times, except urea in November and July and phosphate in May. CONCLUSION: The young cattle showed significantly reduced GPX activities from September to January, and reduced TEAC concentrations particularly in January and March. Decreased GPX activity is indicative of a low selenium supply. Among other disadvantages, this is unfavorable for the development of heifers. A reduced provision with antioxidant agents, particularly vitamin E and ß-carotene, is indicated by the TEAC and has negative effects that are comparable to those caused by a lack of selenium. In terms of health prophylaxis, particularly during winter, specific attention should be given to the supply of sufficient trace elements and good quality silage.

[Age-related changes in antioxidant parameters in healthy calves between the first day of life and the 18th month taking into consideration selected metabolic parameters]. / Altersabhängige Veränderungen antioxidativer Parameter bei gesunden Kälbern zwischen dem 1. Lebenstag und dem 18. Lebensmonat. Untersuchung unter Berücksichtigung ausgewählter Stoffwechselparameter.

OBJECTIVE: To follow the age-dependent development of anti-oxidative metabolic parameters in healthy cattle from birth until 18 months of age. MATERIAL AND METHODS: Blood samples from healthy female cattle were collected at days 1 and 7 post natum (p. n.) and during the 1st, 3rd, 6th, 9th, 12th and 18th month p. n. The antioxidant parameters superoxide dismutase (SOD), glutathione peroxidase (GPX) and Trolox equivalent antioxidative capacity (TEAC), haematocrit (Hct) and the metabolic parameters total protein, albumin, bilirubin, calcium, inorganic phosphate, iron, urea, cholesterol, ß-hydroxybutyrate, alkaline phosphatase, aspartate transaminase, glutamate dehydrogenase, creatine kinase and haptoglobin were determined. RESULTS: All three antioxidant parameters displayed a comparable time-course, with a maximum at 6 months p. n. With the exception of the 9th month p. n., significantly positive correlations were found constantly. GPX activity increased continuously from 50-80 U/ml Hct on day 1 p. n. to 100-190 U/ml Hct in the 6th month p. n. The significantly lowest activities were found on the 1st and 7th day p. n. SOD activity at the 1st (4500-5600 U/g haemoglobin [Hb]) and 7th day p. n. were significantly lower than in the 1st and 3rd month p. n. Activi- ties at 12 and 18 months displayed significantly lower values com- pared to the 1st, 3rd and 6th (5000-9100 U/g Hb) month p. n. The increase in the TEAC concentration from 220-290 µmol/l on day 1 to 260-340 µmol/l in the 6th month p. n. was non-significant. Thereafter, a significant decrease in the concentrations (p>0.05) was found. CONCLUSION: Parallel trends for SOD, GPX and TEAC found in this study indicate a fully functioning antioxidant defence system in the calf, which is well adjusted to and able to compensate the inevitable oxidative stress of birth, onset of respiration, haemoglobin remodelling, forestomach development and other physiological processes.

Use of thermography to monitor sole haemorrhages and temperature distribution over the claws of dairy cattle.

Subclinical laminitis, an early pathological event in the development of many claw diseases, is an important factor in the welfare and economics of high-producing dairy cows. However, the aetiology and pathogenesis of this complex claw disease are not well understood. The present study investigated to what extent thermographic examination of claws is able to give information about corium inflammation, and whether the technique may be used as a diagnostic tool for early detection of subclinical laminitis. Moreover, the temperature distribution over the individual main claws was investigated to obtain further knowledge about pressure distribution on the claws. For this purpose the claws of 123 cows were evaluated in the first week after calving as well as after the second month of lactation for presence of sole haemorrhages (a sign of subclinical laminitis). Furthermore, the ground contact area was analysed by thermography. Sole haemorrhages were significantly increased by the second month of lactation. Thermography showed clear differences between the claws of the front limbs and hindlimbs, as well as between lateral and medial claws. Although the distribution of sole haemorrhages was consistent with the pattern of the temperature distribution over the main claws, no clear correlation was found between the claw temperature after calving and the visible laminitis-like changes (sole haemorrhages) eight weeks later.

[Potential involvement of selenium in the occurrence of milk fever in cattle]. / Potenzielle Bedeutung des Spurenelements Selen für die Entstehung der Gebärparese beim Rind.

OBJECTIVE: Frequent occurrence of parturient paresis (milk fever [MF]) and a partly unsatisfactory treatment success raises the question as to whether in addition to the known causes, other factors influence the incidence and success of MF treatment. Trace elements, including selenium (Se), are involved in bone metabolism, however, there is little knowledge regarding the influence of Se on MF development. The aim of this study was to analyse the concentrations of Se and the statistical relationships to parameters associated with Se influence in downer cows. MATERIAL AND METHODS: A total of 195 Simmental cows, downer cows and clinically healthy control animals were divided into five groups: a) control group (CG, n = 21), b) all cows with MF (n = 174), c) MF cows without additional diseases (n = 145), d) cows with MF and mastitis (n = 10) and e) cows with MF and retained placenta or endometritis (n = 19). Se, calcium (Ca), inorganic phosphate (Pi), tumour necrosis factor α (TNFα), haptoglobin (Hp), antioxidants (Trolox Equivalent Antioxidative Capacity: TEAC) and further metabolic parameters were analysed in the blood serum. RESULTS: The serum concentrations of Se, Ca, Pi and TEAC were lower in groups b) to e), whereas Hp was higher than in the CG (p ≤ 0.05). Se was positively correlated with Pi in the CG, in groups b) and c) with Ca, Pi, K and Mg and in group c) with Hp (p ≤ 0.05). Both Ca and Pi were significantly lower in group c) compared to group d) (p ≤ 0.05). TNFα was increased in groups b) and c) compared to group a) and correlated with Se in group e) (p ≤ 0.05). Alkaline phosphatase activity in groups b) and e) was lower than in the CG and correlated with Se in the CG and group b) (p ≤ 0.05). CONCLUSION: These results, in agreement with the literature data, support the hypothesis that Se could be directly involved in bone metabolism and therefore in the pathogenesis of MF. Se acts via cytokines on Ca mobilization from bone. The concentrations of Hp and TEAC support this interpretation. Therefore, control of the Se status and Se supplementation of cows should be included in the prevention and advanced therapy of MF.

[The relevance of the trace elements zinc and iron in the milk fever disease of cattle]. / Bedeutung der Spurenelemente Zink und Eisen bei der Gebärparese des Rindes.

OBJECTIVE: The aim of this study was to analyse the concentrations of Zn and Fe as well as their relationships to metabolic parameters in milk fever cows. MATERIAL AND METHODS: A total of 195 Simmental cows, downer cows and clinically healthy control animals were divided into five groups: a) control group (CG, n = 21), b) all cows with milk fever (MF) (n = 174), c) MF cows without additional diseases (n = 145), d) cows with MF and mastitis (n = 10) and e) cows with retained placenta or endometritis (n = 19). Selenium (Se), zinc (Zn), iron (Fe), calcium (Ca), inorganic phosphorus (Pi), tumour necrosis factor α (TNFα), haptoglobin (Hp), antioxidants (Trolox Equivalent Antioxidative Capacity: TEAC), non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB), bilirubin, urea, creatinine, glucose, cholesterol, gamma-glutamyl transferase (GGT) and alkaline phosphatase (AP) were analysed in the blood serum. RESULTS: The concentrations of Zn, Fe, Ca, Pi and TEAC were lower in groups b) to e) whereas Hp was higher than in the CG (p ≤ 0.05). In group c), lower Ca and Pi concentrations were found when compared to groups d) and e) (p ≤ 0.05). In group e), Zn concentrations were significantly lower than in group c) (p ≤ 0.05). Zn was negatively correlated with K (CG) and positively correlated with TEAC, Cu, Mn and Fe (groups b and c) and with Mn (group e) (p ≤ 0.05). Fe was positively correlated with Ca (group c), Pi (group c), K (groups b and c) and Mg (groups b-d) as well as with Zn, Cu and Se (groups b and c) (p ≤ 0.05). In groups b) and c), TNFα was increased and negatively correlated with Fe (p ≤ 0.05). AP activity in groups b) and e) was lower than in the CG (p ≤ 0.05). CONCLUSION: These results and literature data support the hypothesis that Zn and Fe could be engaged in bone metabolism and be involved in the pathogenesis of MF. The concentrations of Hp and TEAC support this interpretation. Control of the Zn and Fe status of cows and Zn supplementation should be included in the prevention and advanced therapy of MF.

[Blood serum vitamin B12 concentration in dairy cows during early lactation]. / Vitamin-B12-Konzentration im Blutserum von Milchkühen in der Frühlaktation.

OBJECTIVE: To describe the characteristics of the blood serum vita- min B12 concentration of dairy cows post partum (p. p.) and to investigate its relationship with metabolic parameters, the erythrogram and the health status of the cows. MATERIAL AND METHODS: Blood samples from 157 Holstein-Friesian-cows were obtained for metabolic analysis at 2-6 days p. p. and at 4-5 weeks p. p. In addition, clinical findings were compiled to evaluate the health status (healthy/morbid). RESULTS: In all animals a decline in the vitamin B12 concentration (p ≤ 0.05) at 4 weeks p. p. was observed. Animals of both groups (healthy/morbid) had higher values for the erythrocyte count, haematocrit and haemoglobin concentration 2-6 days p. p. when compared to 4 weeks p. p. In all cows, gamma-glutamyl transferase (GGT) activity was closely correlated to the vitamin B12 concentration (p ≤ 0.01). Furthermore, all animals displayed elevated concentrations of beta-hydroxybutyrate, non-esterified fatty acids and bilirubin (p ≤ 0.05) at 2-6 days p. p. as a consequence of partus-dependent increased lipolysis. There was a smaller decrease in the vitamin B12 concentration in the morbid cows compared to the healthy cows (p   ≤   0.05). CONCLUSIONS AND CLINICAL RELEVANCE: The vitamin B12 concentration is significantly dynamic during lactation and displays a close relationship with the GGT activity and the parameters of energy metabolism. Vitamin B12 may act as an indicator for increased lipolysis and cholestasis. Higher vitamin B12 concentrations may indicate clinical problems. A relationship with haematopoiesis is recognizable from the red cell readings. Decreasing red cell readings associated with reduced performance could be related to a low vitamin B12 concentration. The close correlations of vitamin B12 with GGT activity and bilirubin concentration may indicate cholestatic metabolic stress in dairy cows at blood serum concentrations ≥ 227 ng/l (3rd quartile 2-6 days p. p. healthy group). Morbid cows can already be identified at the subclinical stage.

[Relationship between natal course and metabolic parameters during the peripartal period in cattle]. / Zusammenhang zwischen Geburtsverlauf und stoffwechselrelevanten Parametern im peripartalen Zeitraum beim Rind.

OBJECTIVE: To evaluate metabolic disorders in high-yielding cattle du- ring the peripartal period, the relationship between the course of the delivery and relevant metabolic parameters (insulin-like growth fac-tor 1 [IGF-1], cortisol and non-esterified fatty acids [NEFA]) were examined. MATERIAL AND METHODS: A total of 28 heavily pregnant cows (13 primiparous and 15 multiparous) with normal and difficult natal courses, respectively, were included in the study. Serum IGF-1, NEFA and cortisol were analysed between day 14 ante partum (a. p.) and day 14 post partum (p. p.), IGF-1 and cortisol were also determined in the newborn calves. RESULTS: An elevated stress situation was present for all heifers primarily at birth, because their serum IGF-1 levels were lower (114 ± 11 vs 158 ± 28 ng/ml) while NEFA and cortisol values were higher (896 ± 76 vs 705 ± 58 µmol/l, p = 0.05; 6.51 ± 1.14 vs 4.67 ± 0.46 ng/ml, p = 0.039, respectively) than those of the cows. During the entire examination period, metabolic disorders could be found in animals with difficult birth, based on significantly lower IGF-1 values (p = 0.003; heifers: p < 0.001), significantly higher NEFA levels (at birth p = 0.05) and higher cortisol values compared to the animals with a normal birth. Similar to their mothers, newborn calves of heifers with dystocia had significantly higher cortisol (p = 0.003) at birth and lower IGF-1 levels (p = 0.002) p. p. compared to calves with a normal natal course. CONCLUSION AND CLINICAL RELEVANCE: Identification and prevention of natal disorders in cattle is very important, especially with regard to animal welfare and economics. In this study, difficult natal courses were associated with altered blood serum concentrations of IGF-1, NEFA and cortisol, which consequently reflect an elevated stress situation during the peripartal period. Furthermore, with regard to these results, it can be concluded that heifers with dystocia are affected by an increased metabolic stress situation mainly during the antepartal period, while multiparous cows suffer from metabolic disorders primarily in the period after birth.

[Interrelationship between peripartal metabolism, performance, morbidity and productive life in a herd of Holstein-Friesian heifers]. / Beziehungen zwischen peripartalem Stoffwechsel, Leistung sowie Morbidität bei Holstein-Friesian-Kalbinnen eines Bestandes und deren Nutzungsdauer.

OBJECTIVE: The aim of this study was to determine the relationship between the heifers' peripartal metabolism, milk yield data and the productive life achieved. Furthermore, the influence of fertility, back fat thickness and morbidity on the productive life was evaluated. MATERIAL AND METHODS: Metabolic data and back fat thickness measurements, determined between 2004 and 2005 in a herd of Holstein-Friesian dairy cows, were analysed retrospectively. Additionally, the age reached by the 207 (at that time) heifers as well as data on culling, fertility, milk yield and morbidity were determined with the help of the herd management system and related to the laboratory findings. RESULTS: Heifers with the shortest productive life of < 12 months had the significantly lowest (p < 0.0001) milk yield. The shortest productive life of < 12 months was associated with the significantly lowest (p < 0.0001) oestradiol concentrations 3 days post partum (p. p.) and the significantly smallest (p < 0.0001) albumin concentrations p. p. Furthermore, heifers with the shortest productive life of < 12 months had the significantly lowest (p < 0.0001) cholesterol concentrations 28 days ante partum (a. p.) and p. p. The data showed that heifers with a short productive life had a tendency for lower back fat thickness, tendencially lower oestradiol concentrations 10 days a. p., a trend to lower fertility (regarding inseminations per animal) and an increased incidence of mastitis, stillbirths and endometritis. CONCLUSION AND CLINICAL RELEVANCE: The lowest albumin and cholesterol concentrations of the heifers with a short productive life arose from an inadequate food intake. Oestradiol concentration also decreased during the state of energy deficiency. The low oestradiol concentrations 10 days a. p. can lead to repeated stillbirths in such heifers, and this increased the number of clinical endometritis. Furthermore, the low milk yield corresponded with an energy deficiency in these heifers. These results were supported by the low back fat thickness of these animals, which consequently led to poor fertility. As a consequence, for a longer productive life, special attention should be paid to heifers during the periparturient period, in particular focusing on their food intake and body condition.

[Comparative examination of selected blood parameters from different sampling sites in high yielding cows. Practical usability of blood sampling from the udder vein for metabolic analyses]. / Vergleichende Betrachtung ausgewählter Blutparameter von Hochleistungskühen bei unterschiedlichen Entnahmestellen. Praktische Nutzbarkeit der Blutentnahme aus der Eutervene für Stoffwechseluntersuchungen.

OBJECTIVE: The aim of the present study was to evaluate different statements in the literature on the influence of the sampling site on various blood parameters in a larger amount of animals. In addition, the practical usability of blood sampling from the udder vein or other accessible veins (e. g. saphenous vein or tail vein) in comparison to the jugular vein for metabolic analyses should be verified. MATERIAL AND METHODS: For this purpose blood samples from 92 cows and heifers were taken from the jugular vein, the udder vein and the saphenous vein of the left and right hind limb at four different time points (from 3 weeks ante partum until 8 weeks post partum) and comparatively investigated. RESULTS: For five of the 16 investigated parameters (free fatty acids, beta-hydroxybutyrate, glucose, creatine kinase, and calcium) partially high significant differences between the sampling sites became apparent, dependant on the moment of analysis. CONCLUSION AND CLINICAL RELEVANCE: In metabolic analyses, which comprise the aforementioned parameters, the blood sampling site has decisively influence and has to be considered in the interpretation. The udder vein represents no alternative for blood sampling in high yielding cows for metabolic analyses. For obtaining meaningful results, the jugular vein has to be used for blood sampling, despite the higher procedural effort. An exception is the determination of the creatine kinase activity. Since defence movements of the animal's neck seem to have an influence on the local activity, the udder vein should be preferred as sampling site.

Peritoneal inflammatory response to surgical correction of left displaced abomasum using different techniques.

The objective of this study was to compare the inflammatory response within the abdominal cavity between three surgical methods. The study comprised 45 cows with left displacement of the abomasum, which were allocated into three groups (n = 15). Right flank laparotomy and omentopexy (group R), left flank laparotomy and omentopexy (group L), and laparoscopic abomasopexy (group J) have been applied. Laparoscopic abomasopexy was the only technique that requires perforation of the abomasal wall. Blood and peritoneal fluid (PF) samples were obtained before, and on days 1, 2 and 3 after surgery. Macroscopic and microscopic evaluation of PF were performed. Cytological and biochemical parameters were analysed in blood and PF. No bacteria were present in PF after surgery. The number of PF leukocytes increased in all groups on day 1 after surgery with the highest value after laparoscopy (median, 1st quartile, 3rd quartile, R: 13.1, 6.4, 16.0; L: 13.6, 9.9, 17.4; J: 33.7, 21.1, 46.9 G/l). Laparotomy resulted in an increase of blood and PF CK on day 1 after surgery, whereas, laparoscopy caused an increased PF CK only. All groups had elevated PF D-dimer concentrations before surgery, with further increase in groups R and L on day 1 after surgery.

Peritoneal fluid analysis in dairy cows with left displaced abomasum and abomasal volvulus.

Peritoneal fluid (PF) was evaluated in 40 cows with left displaced abomasum (LDA) and 15 cows with abomasal volvulus (AV). PF was obtained by abdominocentesis at the right ventral abdomen at admission. Simultaneously, a blood sample was taken from the jugular vein. Biochemical and cytological variables in blood and PF specific for ischaemia, inflammation and cell damage were compared. Total protein, albumin, glucose and cholesterol were normal in PF of cows with LDA and AV. Although L-lactate increased in both groups, cows with AV had significantly higher values (LDA: 1.47/0.69/2.68 mmol/l; AV: 6.45/4.55/12.89 mmol/l (median/1. quartile/3. quartile)). D-dimer (LDA: 0.50/0.22/0.88 mg/l; AV: 1.11/0.40/1.85 mg/l) and LDH (LDA: 663/437/943 U/l; AV: 1099/750/1439 U/l) were only increased in PF of cows with AV. The number of leucocytes was normal; however, significantly more peritoneal neutrophils appeared necrotic or apoptotic after AV. PF of cows with abomasal displacement showed distinctive features of ischaemia and inflammation. Characteristics of haemostatic dysfunction and cell damage were mainly evident in PF of cows with AV. The results suggest that anti-inflammatory therapy is indicated in each cow with abomasal displacement. Additionally, medical treatment should be directed to prevent complications of ischaemia and reperfusion in cows with AV.

Effect of multiple intravenous injections of butaphosphan and cyanocobalamin on the metabolism of periparturient dairy cows.

Numerous adjunct therapeutic agents have been investigated for the treatment or control of fat mobilization syndrome in periparturient dairy cows. The aim of this study was to determine the effects of multiple i.v. injections of 10% butaphosphan and 0.005% cyanocobalamin combination (Catosal, Bayer Animal Health, Leverkusen, Germany) between 1 and 2 wk antepartum (a.p.) on the metabolism and health of dairy cows. Forty-five late-gestation Holstein-Friesian cows (second pregnancy) were allocated randomly to 1 of 3 groups with 15 cows/group: group C6 (6 daily i.v. injections of butaphosphan at 10 mg/kg of body weight (BW) and cyanocobalamin at 5 microg/kg of BW in the last 2 wk of gestation); group C3 (3 daily i.v. injections of butaphosphan at 10 mg/kg of BW and cyanocobalamin at 5 microg/kg of BW in the last week of gestation); and group C0 (equivolume daily i.v. injections of 0.9% NaCl solution). Serum biochemical analysis was performed on jugular venous blood samples that were periodically obtained a.p. and postpartum (p.p.). Health status and milk production were monitored p.p. Serum cyanocobalamin concentration increased in groups C6 and C3 p.p. Multiple daily i.v. injections of Catosal before parturition increased p.p. glucose availability, as evaluated by p.p. serum glucose concentration, and decreased peripheral fat mobilization and ketone body formation, as evaluated by p.p. serum nonesterified fatty acid and beta-OH butyrate concentrations. The number of puerperal infections in the first 5 d after calving was decreased in group C6, relative to group C0. We conclude that multiple injections of Catosal during the close-up period have a beneficial effect on the metabolism of periparturient dairy cows. Our results are consistent with the hypothesis that high-producing dairy cows in early lactation may have a relative or actual deficiency of cyanocobalamin.

Diagnostic accuracy of d-dimer and other peritoneal fluid analysis measurements in dairy cows with peritonitis.

BACKGROUND: Peritoneal fluid analysis in cattle traditionally includes the classic parameters despite the fact that they have only moderate diagnostic accuracy and often fail to identify the pathogenesis or etiological factors. Therefore additional parameters recently have been established to improve diagnostic precision. In a recent study, reference ranges for several of these parameters have been proposed in dairy cows. HYPOTHESIS/OBJECTIVES: The aim of this observational study was to assess the diagnostic value of D-Dimer and other measurements of peritoneal fluid analysis in dairy cows with peritonitis. ANIMALS: The study included 110 Holstein-Friesian cows grouped into cows with peritonitis (n = 47) and cows without peritonitis (n = 63). METHODS: Peritoneal fluid was obtained by abdominocentesis. Total protein, albumin, glucose, cholesterol, fibrinogen, l-lactate, D-Dimer, lactate dehydrogenase (LDH), alkaline phosphatase, creatine phosphokinase, white blood cell, and red blood cell were determined in peritoneal fluid and venous blood. Serum-ascites albumin gradient (SAAG) and ratios of peritoneal fluid-venous blood were calculated. Sensitivity (SN) and specificity (SP) were calculated and receiver operating characteristic curve analysis performed. RESULTS: Peritoneal fluid D-Dimer was most accurate in diagnosing peritonitis in cows (SN and SP>95.0%). Total protein concentration, LDH and LDH ratio, and SAAG had sensitivities between 49.0 and 67.1%, and specificities between 88.4 and 95.5%. A low-peritoneal fluid glucose concentration was found to be highly indicative of septic peritonitis. CONCLUSIONS AND CLINICAL IMPORTANCE: Measurement of the recently introduced parameters may increase the diagnostic value of peritoneal fluid analysis and provide additional specific information. Therefore these measurements should be included in the routine procedure.

Activity of hepatic but not skeletal muscle carnitine palmitoyltransferase enzyme is depressed by intravenous glucose infusions in lactating dairy cows.

A positive energy balance in dairy cows pre-partum may decrease hepatic carnitine palmitoyltransferase (CPT) enzyme activity, which might contribute to disturbances of lipid metabolism post-partum. The purpose of this study was to investigate whether skeletal muscle CPT activity can also be downregulated during positive energy balance. Mid-lactating dairy cows were maintained on intravenous infusion of either saline (control) or glucose solutions that increased linearly over 24 days, remained at the 24-day level until day 28 and were suspended thereafter. Liver and skeletal muscle biopsies, as well as four diurnal blood samples, were taken on days 0, 8, 16, 24, and 32, representing infusion levels equivalent to 0%, 10%, 20%, 30% and 0% of the net energy for lactation (NE(L)) requirement respectively. Glucose infusion increased serum insulin concentrations on day 16 and 24 while plasma glucose levels were increased at only a single time point on day 24. Serum beta-hydroxybutyric acid concentrations decreased between day 8 and 24; whereas changes in non-esterified fatty acids were mostly insignificant. Total lipid contents of liver and skeletal muscle were not affected by treatment. Hepatic CPT activity decreased with glucose infusion (by 35% on day 24) and remained decreased on day 32. Hepatic expression levels of CPT-1A and CPT-2 mRNA were not significantly altered but tended to reflect the changes in enzyme activity. In contrast to the liver, no effect of glucose infusion was observed on skeletal muscle CPT activity. We conclude that suppression of CPT activity by positive energy balance appears to be specific for the liver in mid-lactating dairy cows.

Expression and activity of key hepatic gluconeogenesis enzymes in response to increasing intravenous infusions of glucose in dairy cows.

The present study aimed at investigating whether increasing concentrations of glucose supply have a depressive effect on the mRNA abundance and activity of key gluconeogenic enzymes in dairy cows. Twelve Holstein-Friesian dairy cows in mid-lactation were intravenously infused with saline (SI; n = 6) or a 40% glucose solution (GI; n = 6). For GI cows, the infusion dose increased by 1.25%/d relative to the initial NE(l) requirement until a maximum dose equating to surplus 30% NE(l) was reached on d 24. Cows receiving SI received an equivalent volume of 0.9% saline solution. Blood samples were taken every 2 d, and liver biopsies were collected every 8 d. A treatment x quadratic dose interaction (P < 0.01) was observed for the concentration of plasma glucose and serum insulin. The interactions were due to positive quadratic responses of the concentrations of glucose and insulin for GI cows, whereas the concentrations of glucose and insulin did not change over time for SI cows. The concentration of beta-hydroxybutyric acid (BHBA) and serum urea nitrogen (BUN) responded in a treatment x quadratic dose manner, such that greater decreases (P < 0.01) in BHBA and BUN concentrations were observed for cows receiving GI than SI as the dosage increased. Serum NEFA concentration tended to follow a similar pattern as serum BHBA and BUN; however, the interaction was not significant (P = 0.07). The mRNA abundance of gluconeogenesis enzymes followed a linear treatment x dose interaction (P < 0.05) for only pyruvate carboxylase (PC), which was paralleled by a trend for a linear treatment x dose interaction (P = 0.13) for PC enzyme activity. The least PC expression and activity were observed at the largest glucose dosage. The activity, but not mRNA abundance, of fructose 1,6-bisphosphatase (FBPase) showed treatment x quadratic dose interactions (P < 0.05) with decreasing activity at increasing glucose dose. Activities and expression of phosphoenolpyruvate carboxykinase and glucose 6-phosphatase were not affected (P > 0.25) by treatment. In conclusion, hepatic gluconeogenic enzymes are only moderately affected by slowly increasing glucose supply, including a translational or posttranslational downregulation of FBPase activity and a decrease in the mRNA abundance of PC with possible consequences for PC enzyme activity.

Biochemical constituents of peritoneal fluid in cows.

Samples of peritoneal fluid and jugular venous blood were taken simultaneously from 95 clinically healthy Holstein-Friesian cows. The concentrations of total protein, albumin, glucose, cholesterol, fibrinogen, L-lactate and D-dimer, the activities of lactate dehydrogenase (LDH), alkaline phosphatase and creatine kinase, and the white blood cell count were determined in the samples. Light's criteria, the serum-ascites albumin gradient (SAAG) and the ratios of the concentration of each parameter in peritoneal fluid to its concentration in blood were calculated. The mean concentrations of total protein, albumin and D-dimer, the activity of LDH and the SAAG were different from the reference values for monogastric animals and human beings.

Increasing intravenous infusions of glucose improve body condition but not lactation performance in midlactation dairy cows.

The present study was intended to test whether intravenously applied glucose would elicit dose effects on lactation performance similar to those observed after gastrointestinal glucose application. Six midlactation cows received intravenous glucose infusions (GI), increasing by 1.25% of the calculated net energy for lactation (NE(L)) requirement per day, whereas control cows received volume-equivalent saline infusions (SI). Measurements and samples were taken at surplus glucose dose levels of 0, 10, 20, and 30% of the NE(L) requirement, respectively. Body weight and backfat thickness increased linearly with increasing glucose dose for cows on GI compared with SI. No differences were observed in daily feed intake, milk energy output, and energy-corrected milk yield between treatments. However, milk protein percentage and yield increased linearly with the dose of glucose infused in the GI group. Although milk lactose was not affected by treatment during the infusion period, milk lactose percentage and yield decreased for GI, but not SI, once infusions ceased. Based on 5 diurnal blood samples, daily mean and maximum concentrations of plasma glucose and serum insulin showed linear increases with increasing GI, whereas their daily minimum concentrations were unaffected. At GI of 30% of the NE(L) requirement, marked hyperglycemia and hyperinsulinemia were observed at 1600 h (i.e., 1 h postprandially), coinciding with glucosuria. The revised quantitative insulin-sensitivity check index indicated linear development of insulin resistance for the GI treatment but no such change in SI cows. Glucose infusion decreased daily mean and maximum serum beta-hydroxybutyrate and daily minimum nonesterified fatty acid concentrations relative to SI, whereas serum urea nitrogen was only numerically decreased by GI. No changes were observed in the serum activities of gamma-glutamyl transferase and aspartate transaminase and in the serum concentrations of bilirubin and macrominerals. However, serum phosphorus concentration increased after withdrawal of GI, but not SI. Only in GI cows did glycogen content increase or tend to increase linearly in the liver and skeletal muscle. In conclusion, midlactation dairy cows on an energy-balanced diet directed intravenously infused glucose predominantly to body fat reserves rather than increasing lactation performance. This may suggest that the metabolic fate of glucose is modified by metabolic signals, hormonal signals, or both from the portal-drained viscera when absorbed from the intestine.

Effect of several doses of zeolite A on feed intake, energy metabolism and on mineral metabolism in dairy cows around calving.

The object of the present study was to determine the influence of different zeolite A doses on dry matter intake (DMI) and mineral metabolism, and to evaluate an optimum dosage for preventing hypocalcaemia. Eighty pregnant dry cows were assigned to four groups (I-IV). They were fed a total mixed ration (TMR) ad libitum. Groups II, III and IV received an average daily dose of 12, 23 and 43 g zeolite A/kg DM for the last 2 weeks prepartum. Individually DMI was recorded daily. Blood and urine samples were taken before, during and after zeolite A supplementation. Serum was analysed for Ca, Mg, P(i), K, non-esterified fatty acids and beta-hydroxybutyrate (BHB). Urine was analysed for Ca, Mg, P(i), K and net acid-base excretion (NABE). After calving, milk yield (fat corrected milk) and milk composition were determined. During zeolite A supplementation, mean DMI of Group IV (7.3 +/- 1.3 kg/cow/day) was significantly lower compared to Groups I-III (10.1, 10.9, 9.5 kg/cow/day). The reduced feed intake of Group IV resulted in significantly increased BHB as well as decreased NABE after calving. Zeolite A supplementation in higher doses (III and IV) had a stabilizing effect on Ca metabolism around calving for older cows, whereas cows in Groups I and II showed a subclinical hypocalcaemia. The mean serum Mg concentration decreased significantly in older cows in Group IV at calving. The mean P(i) concentration in cows of Group IV decreased into ranges of hypophosphataemia already 1 week after beginning of zeolite A feeding. The mean DMI postpartum as well as the milk yield was not affected by zeolite A supplementation. Feeding of 23 g zeolite A/kg DM TMR prepartum proved to be an adequate dosage for reducing subclinical hypocalcaemia frequency without significant effects on feed intake and P(i) concentration in serum.