Evaluation of an electronic cowside test to detect subclinical ketosis in dairy cows.

The objective of this study was to determine the diagnostic performance of an electronic beta-hydroxybutyrate (BHBA) hand-held meter (Precision Xtra) for use in dairy cattle. Specific objectives were to compare the electronic BHBA meter with serum BHBA concentrations determined photometrically and 2 commonly used chemical cowside tests (Ketostix, Ketolac) and to evaluate accuracy in a field study employing 35 investigators. Of the 196 blood samples collected in experiment 1, 17 (8.7%) contained > or =1,200 micromol of BHBA/L of blood and 10 (5.1%) contained > or =1,400 micromol of BHBA/L of blood. Pearson correlation coefficients were highly significant for all tests. The highest correlation coefficient (0.95) was found between measurements of whole blood BHBA determined with the Precision Xtra test and the serum BHBA concentrations determined photometrically. Correlation coefficients between serum BHBA and BHBA in urine using Precision Xtra and Ketostix, and milk using Ketolac were lower. The Precision Xtra test was both 100% sensitive and specific at > or =1,400 micromol of BHBA/L of whole blood. Using milk and urine, positive and negative predictive values were considerably lower for both chemical tests as well as for the electronic meter. In the second study undertaken with 35 bovine veterinary practices, 926 blood samples were collected. In this study, the Precision Xtra test had sensitivities of 88 and 96% at 1,200 and 1,400 micromol of BHBA/L of whole blood, respectively. Specificities were 96 and 97%, respectively. Level of agreement was lower in the second study employing multiple investigators. Considerable differences in variance occurred among investigators. We conclude that the electronic hand-held BHBA measuring system using whole blood is a useful and practical tool to diagnose subclinical ketosis. Sensitivity and specificity are excellent for a cowside test and higher than 2 commonly used chemical dipsticks (Ketostix and Ketolac).

Prevalence of bovine subclinical endometritis 4h after insemination and its effects on first service conception rate.

The objective of this study was to investigate the prevalence of subclinical endometritis 4h after AI and its effect on first service conception rate (FSCR) in dairy cows. A total of 201 Holstein-Friesian cows with no signs of clinical endometritis were examined 4h after first AI for signs of subclinical endometritis. Endometrial samples were collected from the uterus using the cytobrush technique. The proportion of polymorphonuclear cells (PMN) in the cytological sample was used to characterize an inflammation of the endometrium. Cows were categorized into three groups according to the proportion of PMN in the sample. Cows with 0% PMN (n=115) were assigned to group Zero, cows with >0-15% PMN (n=59) to group Medium, and cows with >15% PMN (n=27) to group High. Pregnancy diagnosis was performed between days 38-44 after AI by palpation of the uterus and its contents per rectum. The FSCR was significantly higher in group Medium than in groups Zero and High (57.6% vs. 39.1% and 29.6%). Statistical analysis revealed an interaction between parity and PMN group. Primiparous cows were at higher risk of being classified into group Medium than multiparous cows (OR=2.27, P=0.01). Primiparous cows in group Zero had lower odds of pregnancy after first AI than primiparous cows in group Medium (OR=0.3, P=0.02). A comparison with cows that were not examined for subclinical endometritis showed that the collection of endometrial samples itself had no effect on FSCR.

Treatment of acute puerperal metritis with flunixin meglumine in addition to antibiotic treatment.

The objective of this field trial was to evaluate effects of a single administration of 2.2 mg/kg of body weight (BW) of flunixin meglumine (FM) in addition to a systemic antibiotic treatment in cows with acute puerperal metritis (APM). Outcome variables tested were proportion of cows with a fever, prevalence of chronic endometritis 18 to 22 and 32 to 35 d in milk (DIM), and reproductive performance measures in the current lactation. In addition, serum concentrations of haptoglobin and fibrinogen were analyzed. Daily milk yield within 6 d after the first treatment was recorded. Cows were examined 4 to 5 DIM by rectal palpation and vaginoscopy, and rectal temperature was measured. Fetid vulvar discharge and a body temperature > or = 39.5 degrees C were signs of APM. Cows with APM were treated in the reference group with 1.0 mg/kg of BW of ceftiofur on 3 to 5 consecutive days (CEF, n = 119). In the study group, cows received the same antibiotic treatment as in CEF and 2.2 mg/kg of BW of FM on treatment d 1 (CEF + FM, n = 119). Blood samples were collected 4, 6, and 10 DIM and analyzed for concentrations of haptoglobin and fibrinogen. A group of cows without APM remained untreated and served as controls (n = 9). There were no significant differences between CEF and CEF + FM in the proportion of cows with fever 1 d after the first treatment (33.6 vs. 46.2%), milk yield per milking 10 DIM (7.5 +/- 0.3 vs. 7.6 +/- 0.3 kg in primiparous, 9.6 +/- 0.4 vs. 10.6 +/- 0.4 kg in multiparous cows), prevalence of chronic endometritis 32 to 35 DIM (64.3 vs. 52.2%), and in reproductive performance (31.5 vs. 34.3% conception to first AI, 58.0 vs. 54.6% pregnancy rate, 107.8 +/- 36.9 vs. 101.6 +/- 41.4 d open). Compared with the control, CEF and CEF + FM had significantly greater concentrations of haptoglobin (1.1 +/- 0.28 vs. 1.9 +/- 0.06 and 1.8 +/- 0.07 mg/mL at 4 DIM; 0.3 +/- 0.15 vs. 1.1 +/- 0.06 and 1.2 +/- 0.07 mg/mL at 10 DIM) and fibrinogen (2.2 +/- 0.17 vs. 3.9 +/- 0.14 and 3.7 +/- 0.13 g/L at 4 DIM; 1.9 +/- 0.1 vs. 2.6 +/- 0.1 and 3.0 +/- 0.13 g/L, respectively, at 10 DIM) on all test days. The additional treatment with FM had no effect on these acute phase proteins. In conclusion, the single administration of 2.2 mg/kg of BW of FM in addition to a systemic antibiotic treatment of cows having APM did not result in beneficial effects on clinical cure, milk yield within 6 d after the first treatment, or reproductive performance.

[Do lactoferrin, lysozyme and the lactoperoxidase-thiocyanate-hydrogen peroxide-system cause negative microbiological results in mastitis secretions?]. / Laktoferrin, Lysozym und das Laktoperoxidase-Thiozyanat-Wasserstoffperoxid-System (LPS) als Ursache negativer mikrobiologischer Befunde aus Mastitissekreten?

Lactoferrin, lysozyme and the lactoperoxidase-thiocyanate-peroxide-system are naturally occurring antimicrobial components of milk. The objective of this study was to examine, whether these components were responsible for negative results, when mastitis milk is cultured microbiologically. Quarter milk samples from 75 cows with clinical mastitis on a dairy farm in Brandenburg were submitted for microbiological culture and analysed for the content and the activities of the three components. Animals from all stages of lactation with clinical mastitis were included in the study. Animals were examined clinically and milk samples were collected prior to first treatment. Secretions from quarters with clinical mastitis were compared to those of neighbouring quarters without clinical mastitis. Secretions with positive cultural results were compared to those with negative results. The concentrations or activities of the three factors were significantly higher in the diseased quarters than in the quarters without clinical signs of mastitis. The concentration of lysozyme increased with severity of the clinical signs (local swelling and changes in secretion). The concentration of lactoferrin was significantly higher in quarters with slight alterations of glandular tissue than in quarters with medium or severe alterations (P < 0.05). LPS-activities did not correlate with the severity of clinical signs. No differences in the concentration of lactoferrin or LPS-activities were seen between mastitis with positive and negative culture results. The concentration of lysozyme was even higher in culturally positive samples than in negative samples (P < 0.05). Results from this study indicate that the three factors examined did not impair the results of microbiological culture of milk samples from quarters with clinical mastitis.