Short communication: Assessment of biomarkers of inflammation in the vaginal discharge of postpartum dairy cows diagnosed with clinical metritis.

Clinical metritis, characterized by the presence of an enlarged uterus and abnormal red-brownish foul-smelling vaginal discharge (VD), is a prevalent condition that causes important economic losses to dairy operations. The accurate diagnosis and treatment of this disease can help decrease its negative effects on the well-being and performance of dairy cows. The objectives of this study were to assess (1) the concentration of haptoglobin (Hp) and neutrophil-derived haptoglobin-matrix metalloproteinase 9 (Hp-MMP 9) in the VD of postpartum cows; and (2) the correlation between Hp and Hp-MMP 9 concentrations in serum and VD. Fifty-three dairy cows from 4 farms in central Pennsylvania were enrolled in this observational study.. Postpartum cows (7 ± 3 DIM) were screened using a Metricheck device to assess VD score (VDS): 1, clear fluid (n = 4); 2, < 50% white purulent fluid (n = 14); 3, > 50% white purulent fluid (n = 8); 4, red-brownish watery fluid without fetid smell (n = 22); and 5, fetid red-brownish watery fluid (n = 5). Blood and VD samples were collected for assessment of Hp and Hp-MMP 9 concentrations. Cows with a VDS of 4 or 5 (VDS4/5) had higher serum Hp concentrations than cows with a VDS of 1, 2, or 3 (VDS1/3; 93 ± 187 µg/mL vs. 59 ± 106 µg/mL, respectively). Similarly, cows with VDS4/5 had higher VD Hp concentrations than cows with VDS1/3 (73 ± 56 µg/mL vs. 17 ± 16 µg/mL, respectively). We found a significant correlation (0.37) between Hp levels in serum and in VD. We found no difference in serum Hp-MMP 9 between VDS4/5 and VDS1/3 cows. The VD concentrations of Hp-MMP 9 were higher in VDS4/5 cows than in VDS1/3 cows (7,629 ± 9,847 ng/mL vs. 1,567 ± 2,165 ng/mL, respectively). The correlation between Hp-MMP 9 in serum and VD was 0.22; nevertheless, it was not statistically significant. Interestingly, Hp and Hp-MMP 9 concentrations were higher in VD samples than in serum, regardless of VDS. Results from this study suggest that inflammatory biomarkers may be increased in cows with a VDS of 4 or 5. Further research should be aimed at elucidating the processes involved in inflammatory biomarker production and transportation in the uterus, as well as the effect of these biomarkers on endometrial cells.

Assessment of daily activity patterns and biomarkers of pain, inflammation, and stress in lactating dairy cows diagnosed with clinical metritis.

The objectives of the present case-control study were to assess (1) daily activity patterns (lying time, number of steps, number of lying bouts, and lying bout duration), and (2) circulating concentrations of biomarkers of pain (substance P), inflammation (haptoglobin), and stress (cortisol) in lactating dairy cows diagnosed with clinical metritis. Lactating dairy cows (n = 200) from 2 commercial dairy herds were enrolled in the present study. Cows diagnosed with clinical metritis (n = 100) at 7 ± 3 d in milk were matched according to lactation and days in milk to cows without clinical metritis (NO-CM; n = 100). On study d 1, clinical metritis was diagnosed (using a Metricheck device, Simcro Tech Ltd., Hamilton, New Zealand) by the presence of watery, reddish, or brownish foul-smelling vaginal discharge, and blood samples were collected for assessment of circulating concentration of substance P, haptoglobin, cortisol, total calcium, ß-hydroxybutyrate, and blood cells. In addition, on study d 1 body condition of cows was visually assessed, and activity monitors were placed on the hind leg of a subset of cows (CM, n = 56; CON, n = 56) and were kept until study d 7. Cows showing any other signs of other diseases were not included in the study. Cows with clinical metritis tended to spend more time lying (CM = 628.92 min/d; NO-CM = 591.23 min/d) compared with NO-CM cows. Activity analysis by parity revealed that primiparous cows with clinical metritis spent more time lying compared with primiparous cows without clinical metritis. However, no differences in daily lying time were observed between multiparous cows with and without clinical metritis. Furthermore, cows in the CM group had a higher circulating concentration of substance P (CM = 47.15 pg/mL; NO-CM = 37.73 pg/mL) and haptoglobin (CM = 233.00 µg/mL; NO-CM = 99.98 µg/mL) when compared with NO-CM cows. Cows with clinical metritis had lower body condition score, and a greater proportion of cows in this group had hypocalcemia when compared with cows without clinical metritis. The circulating concentration of leukocytes and erythrocytes were decreased in cows with clinical metritis compared with cows without clinical metritis. Results from this study showed that concentrations of markers of inflammation, stress, pain, and activity were affected in cows diagnosed with clinical metritis; thus, strategies aimed to minimize the negative effects associated with clinical metritis may be required to improve the welfare of dairy cows.