The effect of antibiotic versus no treatment at dry-off on udder health and milk yield in subsequent lactation: A retrospective analysis of Austrian health recording data from dairy herds.

Bovine mastitis is the most commonly diagnosed disease of dairy cows worldwide and causes extensive economic losses to milk producers. Intramammary infection status before dry-off plays a decisive role with respect to udder health and milk yield in the subsequent lactation. The aim of this study was to compare the effect of antibiotic dry cow therapy (DCT) versus no treatment at dry-off on milk yield, somatic cell count (SCC), inflammation of the mammary gland (IMG), and the incidence of clinical mastitis in the subsequent lactation. Dairy herd data from 251 Austrian dairy farms were recorded over an observation period of 12 mo and subsequently analyzed. The data set included 5,018 dairy cows: 2,078 were treated with antibiotics (abDCT group) and 2,940 were not treated (noDCT group) at dry-off. The abDCT group was subdivided, based on the antimicrobial active substances used for drying off, into 4 different groups (penicillins, cloxacillin, cephalosporins, and rifaximin). Based on bacteriological culture results, infections were grouped into those caused by major, minor, and other pathogens. Additionally, the IMG was defined via SCC from milk recording data using a cutoff of 200,000 cells/mL before drying off and after calving. The incidence of clinical mastitis cases within 30 and 90 d in milk was calculated using veterinary diagnosis data. To investigate the effect of different dry cow therapies on the following parameters: milk yield, SCC, and diagnosed clinical mastitis cases, different linear mixed models were constructed. Overall, the abDCT group was determined to have a significantly higher milk yield over 305 d in milk in the subsequent lactation (increase of 6.18%), compared with the noDCT group (increase of 4.29%). Both groups (abDCT and noDCT) demonstrated a decrease in the first SCC after calving compared with the SCC before dry-off, although the treated cows had a significantly higher reduction. Regarding the different antibiotic groups, with exception of the rifaximin treated cows, all antibiotic groups showed a significant difference from not treated cows with respect to SCC. Additionally, we were able to demonstrate that cows with IMG before dry-off had a 2.073 times higher chance of an increased SCC (>200,000 cells/mL) after calving. With respect to the veterinary diagnosis data, neither the IMG before drying off nor the type of DCT had a significant influence on the probability of developing clinical mastitis within 30 or 90 d in milk. Only a small number of treatments was accompanied with a bacteriological examination before drying off. However, the existing data in this study indicates that the intramammary infection status before dry-off in combination with different dry cow treatments influences udder health and milk yield after calving. Nevertheless, further studies with larger data sets of bacteriological examinations are necessary to enable a more in-depth investigation into the effects of different antibiotic substances used for DCT.

Sonographic and histological udder parenchyma changes after intramammary infection of sheep with Mycoplasma agalactiae.

INTRODUCTION: The sonographic findings of the udder parenchyma and udder lymph nodes in 30 lactating sheep after experimental infection with Mycoplasma agalactiae are described. The objective of the study was to describe infection related changes in the udder parenchyma and udder lymph nodes using physical, sonographic, and histological examination and to detect associations between sonographic and histological changes of the tissues. Animals were intramammarily infected with different mutant cocktails and the wild type PG2. One group served as a negative control. A 15 MHz linear transducer (Esaote MyLab 30 CV, Esaote, Florence, Italy) was used for sonographic examinations. Compared with the uninfected control group with homogeneously granular parenchyma, the udder lymph nodes were larger and the udder parenchyma was more inhomogeneous and partially hyperechoic. The corresponding histological findings in infected mammary glands comprised proliferation of interstitial connective tissue, non-purulent interstitial mastitis, and purulent galactophoritis. The infected udder lymph nodes showed reactive hyperplasia. The findings obtained in this study may improve the diagnosis of Mycoplasma mastitis in sheep.

INTRODUCTION: Les constatations échographiques sur le parenchyme de la mamelle et des ganglions lymphatiques de la mamelle chez 30 brebis en lactation après une infection expérimentale avec Mycoplasma agalactiae sont décrits. L'objectif de l'étude était de décrire les modifications liées à l'infection dans le parenchyme mammaire et les ganglions lymphatiques de la mamelle à l'aide d'un examen physique, échographique et histologique et de détecter les associations entre les altérations échographiques et histologiques des tissus. Les animaux ont été infectés par voie intramammaire avec différents cocktails de mutants et le type sauvage PG2. Un groupe a servi de contrôle négatif. Une sonde linéaire de 15 MHz (Esaote MyLab 30 CV, Esaote, Florence, Italie) a été utilisé pour les examens échographiques. Comparativement au groupe témoin non infecté avec un parenchyme granulaire homogène, les ganglions lymphatiques de la mamelle étaient plus gros et le parenchyme de la mamelle était plus inhomogène et partiellement hyperéchogène. Les résultats histologiques correspondants dans les glandes mammaires infectées comprenaient une prolifération de tissu conjonctif interstitiel, une mammite interstitielle non purulente et une galactophorite purulente. Les ganglions lymphatiques de la mamelle infectée présentaient une hyperplasie réactive. Les résultats obtenus dans cette étude peuvent améliorer le diagnostic de la mammite à Mycoplasma chez le mouton.

In vivo / in vitro Correlation of Pharmacokinetics of Gentamicin, Vancomycin, Teicoplanin and Doripenem in a Bovine Blood Hemodialysis Model.

Background: Elimination of a drug during renal replacement therapy is not only dependent on flow rates, molecular size and protein binding, but is often influenced by difficult to predict drug membrane interactions. In vitro models allow for extensive profiling of drug clearance using a wide array of hemofilters and flow rates. We present a bovine blood based in vitro pharmacokinetic model for intermittent renal replacement therapy. Methods: Four different drugs were analyzed: gentamicin, doripenem, vancomicin and teicoplanin. The investigated drug was added to a bovine blood reservoir connected to a hemodialysis circuit. In total seven hemofilter models were analyzed using commonly employed flow rates. Pre-filter, post-filter and dialysate samples were drawn, plasmaseparated and analyzed using turbidimetric assays or HPLC. Protein binding of doripenem and vancomycin was measured in bovine plasma and compared to previously published values for human plasma. Results: Clearance values were heavily impacted by choice of membrane material and surface as well as by dialysis parameters such as blood flow rate. Gentamicin clearance ranged from a minimum of 90.12 ml/min in a Baxter CAHP-170 diacetate hemofilter up to a maximum of 187.90 ml/min in a Fresenius medical company Fx80 polysulfone model (blood flow rate 400 ml/min, dialysate flow rate 800 ml/min). Clearance of Gentamicin vs Vancomicin over the F80s hemofilter model using the same flow rates was 137.62 mL vs 103.25 ml/min. Doripenem clearance with the Fx80 was 141.25 ml/min. Conclusion: Clearance values corresponded very well to previously published data from clinical pharmacokinetic trials. In conjunction with in silico pharmacometric models. This model will allow precise dosing recommendations without the need of large scale clinical trials.

Measurement of oxygen concentration for detection of subclinical mastitis.

INTRODUCTION: Subclinical mastitis is a frequent and economically important disease in cattle. Since the milk appears macroscopically normal the diagnosis depends on indirect parameters. In automatic milking systems ideally the measurements have to be automatized and completed during milking process. Oxygen concentration of the milk is a parameter which has not been used widely to date. Oxygen is consumed by cells in the milk, hence an increased number of cells results in decreased oxygen concentration. The main objectives of the study were to study the association of milk oxygen concentration with the number of cells and the electric conductivity and to assess the feasibility of oxygen concentration for detection of subclinical mastitis. The study was performed on five dairy farms using 690 macroscopically normal quarter milk samples. Oxygen concentrations (OC), somatic cell count (SCC) and electric conductivity (EC) were measured. The associations between the parameters were calculated and the diagnostic value of OC for detection of subclinical mastitis was estimated. Significant correlations were found between OC and SCC (rs =-0.28) and between OC and EC (rs = -0.20). SCC of the samples varied between 1,000 and 21,602,000 cells/ml. Out of the 690 milk samples 404 had SCC 200,000 cells/ml (subclinical mastitis). OC decreased whereas EC increased significantly with increasing SCC (P < 0.001). The threshold for OC to diagnose subclinical mastitis was 5.22% (sensitivity 84%, specificity 46%). The area under the curve describing the diagnostic value of OC was 0.72 (confidence interval 0.68-0.76). In conclusion OC has potential to be used as parameter to detect subclinical mastitis in dairy cattle. Currently the application is not suitable for routine use. Further research is necessary to improve measurement technology and diagnostic value of the parameter.

INTRODUCTION: La mammite subclinique est une maladie fréquente et économiquement importante chez les bovins. Puisque le lait apparaît macroscopiquement normal, le diagnostic dépend des paramètres indirects. Dans les systèmes de traite automatique, les mesures doivent idéalement être automatisées et effectuées pendant le processus de traite. La concentration en oxygène du lait est un paramètre qui n'a pas été largement utilisé à ce jour. L'oxygène est consommé par les cellules dans le lait, un nombre accru de cellules entraînant donc une diminution de la concentration en oxygène. Les principaux objectifs de l'étude étaient d'étudier l'association de la concentration d'oxygène du lait avec le nombre de cellules et la conductivité électrique et d'évaluer la praticabilité de la mesure de la concentration en oxygène pour la détection de la mammite subclinique. L'étude a été réalisée dans cinq fermes laitières à l'aide de 690 échantillons de lait de quartier macroscopiquement normaux. Des concentrations d'oxygène (OC), le nombre de cellules somatiques (SCC) et la conductivité électrique (EC) ont été mesurés. Les associations entre les paramètres ont été calculées et la valeur diagnostique de l'OC pour la détection de la mammite subclinique a été estimée. Des corrélations significatives ont été trouvées entre OC et SCC (rs= -0,28) et entre OC et EC (rs = -0,20). Le SCC des échantillons variait entre 1'000 et 21'602'000 cellules/ml. Sur les 690 échantillons de lait, 404 avaient un SCC de 200 000 cellules/ml (mammite subclinique). L'OC a diminué alors que l'EC a augmenté de façon significative avec l'augmentation du SCC (P - 0,001). Le seuil pour que l'OC permette un diagnostic de mammite subclinique était de 5,22 % (sensibilité 84 %, spécificité 46 %). La zone sous la courbe décrivant la valeur diagnostique de CO était 0.72 (intervalle de confiance 0.68-0.76). En conclusion, l'OC pourrait être utilisée comme paramètre pour détecter la mammite subclinique chez les bovins laitiers. Actuellement, l'application n'est pas adaptée à une utilisation de routine. D'autres recherches sont nécessaires pour améliorer la technologie de mesure et la valeur diagnostique du paramètre.

Evaluation of a handheld device for the measurement of beta-hydroxybutyrate in capillary blood obtained by the puncture of the vulva as well as in venous whole blood in cattle.

A negative energy balance is a common condition in high yielding dairy cows causing the production of ketone bodies (KB), including beta-hydroxybutyrate (BHB), defined as subclinical ketosis (SCK) if clinical signs are missing. The aim of the present study was to evaluate a handheld electronic device for the detection of SCK (BHB-concentration > 1.2 mmol/l), in capillary blood and venous whole blood in cows (WellionVet BELUA, MED TRUST Handels GmbH, Marz, Austria) as well as the feasibility of the puncture of the external vulva with a single use lancet. For this purpose, the blood BHB-concentration was tested in 250 venous and capillary blood samples and compared to the results of a certified laboratory. The majority (76.3%) of the animals displayed no signs of discomfort related to the puncture and in 74.2% the procedure was successful on the first attempt. The BHB-concentrations detected in capillary blood showed good agreement with the reference method, both in capillary (correlation coefficient 0.94 (p⟨0.001), Kappa-value 0.89) and venous whole blood (correlation coefficient of 0.95 (p⟨0.001), Kappa-value 0.89). Altogether, 98% of all the samples were correctly classified as SCK or non-SCK by the handheld device in capillary blood (sensitivity 0.96, specificity 0.98) and 97.4% in venous whole blood (sensitivity 0.889, specificity 0.991), respectively. An increase in the correlation by the adaptation of the cut off level could not be achieved for both sampling sites.

Retrospective analysis of Austrian health recording data of antibiotic or nonantibiotic dry-off treatment on milk yield, somatic cell count, and frequency of mastitis in subsequent lactation.

Typically, dairy cows are dried off at the end of lactation. During the dry period, intramammary infections may be cured or persist, and new infections may occur. Traditionally, antibiotics (AB) have been used at dry-off. However, blanket antibiotic dry-off treatment may no longer be justifiable and, recently, selective use of antibiotics at dry off has been proposed and different decision criteria suggested. The objective of the study was to evaluate cows receiving antibiotic treatment at dry off (AB group) compared with cows dried off without antibiotics (non-AB group) using a large data set. Primary outcome parameters were milk yield, somatic cell count (SCC), and frequency of mastitis in the subsequent lactation. Additionally, we aimed to calculate cut-off values to determine, at the cow level, whether antibiotic dry-off treatment is indicated. A data set of 88,534 lactations was used; 27,723 cows were dried off using antibiotics (AB group; 31.3%) and 60,811cows were dried off without antibiotics (non-AB group; 68.7%). Milk yield in previous and subsequent lactations was higher in the AB group. Cows in the AB group produced, on average, 91 kg more milk in the subsequent lactation. The average SCC during the final 90 d of the previous lactation and at dry-off did not differ between the 2 groups. The probability of drying off using antibiotics increased almost linearly with higher milk yield and with higher SCC. The use of antibiotics resulted in an average decrease in SCC of 1,500 cells/mL in the subsequent lactation. The frequency of clinical mastitis during the previous lactation was higher in the AB group than in the non-AB group. Independently of the dry-off treatment, this difference remained in the subsequent lactation within 90 d in milk. The use of antibiotics at dry-off had no significant effect on the frequency of mastitis within 90 d in milk of the subsequent lactation. The study indicates that Austrian farmers and veterinarians are applying selective dry-cow treatment using milk yield and, to a lesser extent, SCC and mastitis frequency, for decision-making. However, even though a large data set was used, cut-off values with sufficient diagnostic value for selective dry-cow treatment could not be identified. It is likely that cut-off values must be identified at the herd level or in combination with additional parameters (e.g., results of bacterial culture).

Prevalence of Mycobacterium avium subspecies paratuberculosis and hepatitis E in New World camelids in Austria.

Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of paratuberculosis in domestic ruminants and New World Camelids (NWC). Hepatitis E virus (HEV) is an important public health concern worldwide. The virus has been identified in several species, some of them serving as a reservoir for zoonotic HEV strains. Husbandry and breeding of llamas and alpacas have increased in Austria in recent years. Therefore, the aim of the present study was to evaluate the prevalence of MAP and HEV in NWC in Austria. Altogether 445 animals, originating from 78 farms were enrolled in the study. Of the animals sampled, 184 (41.35%) were llamas and 261 (58.65%) were alpacas. 443 blood samples for MAP-ELISA and 399 faecal samples for quantitative PCR (qPCR) and culture for MAP as well as for HEV detection by RT-qPCR have been collected. All of the 399 animals tested for shedding of MAP were negative by faecal solid culture. Using qPCR, 15 (3.8%) of the animals were MAP positive and 384 (96.2%) negative. Out of the 443 serum samples examined for specific antibodies against MAP by ELISA, 6 (1.4%) were positive, 1 (0.2%) was questionable and 436 (98.4%) samples were negative. All faecal samples were tested negative for HEV.

Clinical parameters and adrenocortical activity to assess stress responses of alpacas using different methods of restraint either alone or with shearing.

Shearing of alpacas is stressful and is undertaken by restraint in the standing position, cast on the floor or on a tilt table. The objectives of the study were to evaluate and compare the stress responses between different methods. The study consisted of two parts. In part one, 15 animals were restrained applying all three methods but without shearing. In part two, 45 animals in three groups of 15 were shorn using one of the three procedures. Body temperature, heart rate, respiratory rate, salivary cortisol and faecal cortisol metabolites (FCM) were measured. Part 1: restraint in a standing position was less stressful than other procedures. Part 2: the classic clinical parameters changed significantly over time but without significant differences between the methods. The number of injuries did not differ. Saliva cortisol and FCM concentrations varied in wide ranges between animals. An increase in FCM concentrations occurred in all groups but saliva cortisol concentration increased only after shearing on the ground. The recommendations of the study are to shear calm alpacas in the standing position but animals showing severe defence reactions should be shorn either cast on the ground or on a table to decrease the risk of injuries.

No detectable carotenoid concentrations in serum of llamas and alpacas.

Carotenoids are lipid-soluble pigments and important for a variety of physiological functions. They are major dietary vitamin A precursors and act as lipophilic antioxidants in a variety of tissues and are associated with important health benefits in humans and animals. All animals must acquire carotenoids from their diet, but to our knowledge, there are no studies investigating the intestinal carotenoid absorption and their blood concentrations in New World camelids. The present study aimed to assess the serum concentrations of selected carotenoids in llamas (n = 13) and alpacas (n = 27). Serum carotenoids as well as retinol (vitamin A) and α-tocopherol (vitamin E) were determined by high-performance liquid chromatography coupled with mass spectrometry and these were unable to detect any carotenoids (α- and ß-carotene, α- and ß-cryptoxanthin, lutein, zeaxanthin, lycopene) in the samples. The concentrations of retinol in alpacas (2.89 ± 1.13 µmol/l; mean ± SD) were higher (p = 0.024) than those found in llamas (2.05 ± 0.87 µmol/l); however, the concentrations of α-tocopherol were not significantly (p = 0.166) different (llamas: 3.98 ± 1.83 µmol/l; alpacas: 4.95 ± 2.14 µmol/l). The results show that both llamas and alpacas are not able to absorb intact carotenoids, but efficiently convert provitamin A carotenoids to retinol.

Metabolic adaptation and reticuloruminal pH in periparturient dairy cows experiencing different lipolysis early postpartum.

Metabolic adaptation includes an array of concerted metabolic and endocrine events that enable dairy cows bridging the period of energy deficit at the onset of lactation. The present study evaluated metabolic, endocrine and reticuloruminal pH changes in 30 (25 Holstein and five Simmental) periparturient dairy cows experiencing variable lipolysis early postpartum. Cows were fed the same close-up and fresh lactation diets and kept in the same management conditions. Blood samples were collected at day 14, and day 4, relative to expected parturition, and at day 2, and day 21 postpartum, and serum metabolites and hormones related to glucose and lipid metabolism, as well as concentrations of several liver enzymes and acute phase proteins were determined. Additionally, reticuloruminal pH was monitored every 10 min over the last 3 days of the observation period. BW and milk yields were recorded and balances of energy and protein were assessed. Based on serum concentration of non-esterified fatty acids (NEFA) postpartum, cows were retrospectively classified into low (n=8), medium (n=11), and high (n=11) lipolysis groups, with NEFA levels of 0.7 mmol/l, respectively. Overall, elevated NEFA concentrations in the High group went along with a higher ratio of NEFA to cholesterol and reduced insulin sensitivity. While serum glucose, energy deficit and BW loss did not differ, cows of the High group exhibited increased lactate concentrations in the serum, compared with the Medium group. No differences in liver enzymes and acute phase proteins were evidenced among fat mobilization groups, whereas concentration of serum billirubin was lowest in the Low group after parturition. Data of milk yield and milk energy output showed no differences among groups, despite divergences in calculated energy balance and BW change postpartum. Cows of the Low group tended to increase dry matter intake but also showed longer time duration of pH below 6.0 in the reticulorumen (on average 299 min/day compared with 99 and 91 min/day for Medium and High groups, respectively). Differences in metabolic, endocrine and reticuloruminal pH responses indicate diverse metabolic adaptation strategies of early-lactation cows to cope with energy deficit postpartum.

[Time point and methods for emergency killing in cattle]. / Zeitpunkt und Durchführung der tierschutzkonformen Nottötung beim Rind.

Emergency killing is defined as the killing of injured or ill animals to avoid excessive pain or harm. Decision-making for emergency killing or a prolonged therapy can be difficult and has to be based on the case history and results of the clinical examination contributing to the prognosis, particularly in downer cows. Evaluation of enzyme activities and total bilirubin can be used as additional factors pointing to a guarded prognosis; however, none of these parameters provides a clear cut-off value indicating a poor prognosis and mandatory emergency killing. Euthanasia by intravenous drug application is seen as the least stressful method of killing and should therefore always be the first method of choice for emergency killing in cattle. Drugs containing pentobarbital as well as a combination of three different drugs (T61-Injektionslösung, MSD Animal Health) are available for euthanasia in cattle. All drugs must be administered by a veterinarian. Before application of pentobarbital, an animal should be deeply sedated. The administration of T61 requires anaesthesia of the animal and it is not licensed for use in pregnant animals. Alternative methods for emeragency killing, including captive bolt stunning and the use of firearms, although not regularly performed by veterinarians, should be assessed concerning their correct application and performance. When captive bolt stunning or emergency killing using firearms is performed, the correct position of the device is crucial as well as a quick exsanguination or the application of a pithing rod for the actual killing of the animal after captive bolt stunning. In addition to medical considerations, economic and personal factors contribute to the decision about emergency killing in cattle. Therefore, veterinarians should aim to evaluate each case thoroughly based on personal knowledge and experience, case history, clinical findings and laboratory parameters to avoid prolonged suffering of the animal.

Concentration of Potassium in Plasma, Erythrocytes, and Muscle Tissue in Cows with Decreased Feed Intake and Gastrointestinal Ileus.

BACKGROUND: Healthy cows consume large amounts of potassium and a sudden loss in appetite can lead to hypokalemia. The routine method to evaluate potassium homeostasis is the measurement of the extracellular potassium in plasma or serum, but this does not provide information about the intracellular potassium pool. HYPOTHESIS/OBJECTIVES: To evaluate potassium homeostasis by comparing the extracellular and intracellular potassium concentration in cows with reduced feed intake and gastrointestinal ileus. ANIMALS: Twenty cows 1-3 days postpartum (group 1) and 20 cows with gastrointestinal ileus (group 2). METHODS: Observational cross-sectional study. Plasma potassium was measured by using an ion-sensitive electrode. Intracellular potassium was measured in erythrocytes and muscle tissue (muscle biopsy) by using inductively coupled plasma optical emission spectroscopy. RESULTS: Cows of group 1 did not have hypokalemia. Overall cows with gastrointestinal ileus were hypokalemic (mean ± SD, 2.9 mmol/L ± 0.78), but potassium concentration in erythrocytes and muscle tissue was not lower than in postpartum cows. Intracellular potassium in erythrocytes varied very widely; group 1: 3497-10735 mg/kg (5559 ± 2002 mg/kg), group 2: 4139-21678 mg/kg (7473 ± 4034 mg/kg). Potassium in muscle tissue did not differ between group 1 (3356 ± 735 mg/kg wet weight) and group 2 (3407 ± 1069 mg/kg wet weight). No association between extracellular and intracellular potassium concentrations was detected. CONCLUSIONS AND CLINICAL IMPORTANCE: That measurement of plasma potassium concentration is not sufficient to evaluate potassium metabolism of cows.

Effects of wheat protein in milk replacers on abomasal emptying rate in calves.

Diarrhoea is a condition with tremendous impact on calf health. Infectious agents play a dominant role; however, non-infective factors may also contribute to pathogenesis of diarrhoea. One factor, the abomasal emptying rate, is mainly influenced by the composition of feed. The aim of the study was to assess the influence of different protein sources in milk replacers on abomasal emptying rate and clinical parameters. The effect of increasing age of the calves on abomasal emptying was also evaluated. The study compared abomasal emptying rates and clinical parameters in calves, which were fed either milk replacer containing only whey protein or one which partially contained wheat protein. Abomasal emptying rate was estimated by ultrasonography. Ten calves were used in the study over 18 days, and each calf was fed 3 periods of 3 days length using different milk replacers in an alternating crossover design. The abomasum was emptied significantly faster when the wheat protein containing milk replacer was fed (half-emptying time wheat protein 49.1 ± 4.1 min, half-emptying time milk protein 59.1 ± 7.4 min); however, clinical parameters and weight gain did not differ between the feeding regimes. Age did not significantly influence abomasal emptying rate. As milk replacers containing wheat proteins increased abomasal emptying rate, they may have a higher potential to initiate diarrhoea, especially if high volumes are fed. Thus, the feeding regimes are likely to be even more important when such milk replacers are used.

Randomised prospective study compares efficacy of five different stomach tubes for rumen fluid sampling in dairy cows.

The objective of the study was to compare the performance of five types of stomach tubes for rumen fluid sampling. Rumen fluid was sampled in rumen fistulated cows assigned to a 5×5 Latin square study design. The pH values of samples taken by stomach tubes and via fistulas were measured; the results were compared with indwelling sensor measurements. The practicability of the stomach tubes for regular use was tested in the field. Rumen fluid samples were obtained rapidly. Volumes for transfaunation could be obtained. The pH-values of samples taken with the four out of the five tubes (Dirksen, Geishauser, tube 4 and a simple water hose used with a gag) did not show significant differences to samples taken via rumen fistulas. Mean differences ranged between -0.02 and +0.09. Samples taken with tube 4 and the water hose showed also no significant differences to pH-sensor measurements. This study demonstrates that stomach tubes are suitable for rumen fluid sampling. Tube 4 seems to be the best probe for work in the field. It was well tolerated by the animals, saliva contamination is negligible. We, therefore, conclude that the evaluation of rumen acid base status in the field is possible.

Comparison of metabolic, hematological, and peripheral blood leukocyte cytokine profiles of dairy cows and heifers during the periparturient period.

The periparturient period presents major physiological challenges for the dairy cow. It is a period that is affected by metabolic stressors, major changes in endocrine status, and altered immune function, which together result in an increased risk of disease. Immunological, hematological, and metabolic profiles from the periparturient period of heifers (primipara) were compared with those of cows (pluripara) to test the hypothesis that at the time of calving they have qualitatively different peripheral blood profiles. Blood samples were collected from 22 Holstein-Friesian animals on 3 occasions: approximately 2 wk before calving, within 24h after calving, and approximately 2 wk after calving. Quantitative PCR was used to measure the expression of a selected set of cytokines and receptors by peripheral blood leukocytes. Additional analyses included hemoglobin concentration, red cell, platelet and white cell counts (total and differentiated), and clinical diagnostic biochemical profiles. Total leukocyte counts, neutrophils, and lymphocytes were higher in heifers than cows before calving and within 24h after calving. Alkaline phosphatase was consistently higher in heifers than cows and several significant differences were observed between the 2 groups with regards to cytokine and cytokine-receptor mRNA expression. The results warrant further investigation from the perspective of identifying risk factors for metabolic and parturient disease in dairy cattle.

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.

Progesterone, pregnanediol-3-glucuronide, relaxin and oestrone sulphate concentrations in saliva, milk and urine of female alpacas (Vicugna pacos) and their application in pregnancy diagnosis.

The pregnancy-associated hormones, progesterone (P4), pregnanediol-3-glucuronide (PdG), relaxin (RLN) and oestrone sulphate (E1S) in plasma, saliva, milk and urine of alpacas were measured in order to assess their potential use for pregnancy diagnosis. Samples were obtained from 36 female alpacas before mating and at different stages throughout pregnancy (confirmed by ultrasonography). The hormone concentrations were determined using enzyme immunoassays. Milk samples were also tested using a commercial on-farm P4 kit, designed for dairy cattle. Although the concentration of P4 in plasma, milk and urine, and the concentration of PdG in urine were significantly higher in pregnant than in non-pregnant alpacas, there was no difference in the concentrations of P4 or PdG in saliva. The on-farm milk P4 kit showed a sensitivity of 90 per cent for diagnosis of pregnancy and a specificity of 69 per cent for non-pregnancy. The concentration of RLN in plasma increased significantly after the second month, and concentration of E1S in plasma and urine during the last month of pregnancy, whereas, there were no significant differences in RLN or E1S concentrations in saliva and milk between pregnant and non-pregnant alpacas. Values of P4, RLN and E1S in plasma, and PdG and E1S in urine are comparable with the previous reports in alpacas and, therefore, can be confirmed as an indicator for pregnancy. This is the first study to include determination of pregnancy-associated hormones in the saliva and milk of alpacas. However, saliva seems to be unsuitable for pregnancy diagnosis in alpacas, whereas, P4 in milk, as well as PdG and E1S in urine, seem to be adequate tools for diagnosis.

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.

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.