Assessment of the effects of prepartum anti-inflammatory therapies on type 1/type 2 immunity ratio using a rapid blood test.

The objective of this study was to assess (1) the effects of prepartum administration of anti-inflammatory therapies on type 1/type 2 immunity ratio using a rapid blood test (D2Dx immunity test; Nano Discovery Inc.), and (2) correlations between rapid blood test scores and daily milk yield in Holstein dairy cows. At 14 d before the expected calving date, cows (n = 64) and heifers (n = 23) were blocked by body condition score (optimal = 3.25-3.5; high ≥3.75) and parity (nulliparous, parous), and randomly allocated to one of 3 treatment groups (1) ASA (n = 29) = receive one oral treatment with administration of acetylsalicylic acid (4 boluses; 480 grain/bolus); (2) MEL (n = 31) = receive one oral administration with meloxicam (1 mg/kg of body weight), or (3) PLC (n = 27) = receive one oral treatment with 4 gelatin capsules filled with water. Blood samples were collected weekly starting 1 wk before treatment until 3 wk after calving for assessment of type 1/type 2 immunity ratio using a rapid blood test (i.e., D2Dx immunity test). A higher D2Dx score corresponds to a higher type 1/type 2 ratio. Furthermore, blood samples were collected within 72 h before and after calving by farm personnel. Daily milk yield for the first 60 d in milk (DIM) was collected from on-farm computer records. The data were analyzed using MIXED procedure of SAS (SAS Institute Inc.) as a randomized complete block design. On average enrolled cows received treatment administration 10 d before the actual calving date (standard deviation = 5.10 d). There was a tendency for a treatment by day interaction. Cows treated with ASA had higher type 1/type 2 ratio within 3 d after calving compared with MEL and PLC cows (ASA = 0.065 ± 0.002; MEL = 0.059 ± 0.002; PLC = 0.053 ± 0.002). Similarly, ASA and MEL cows had a higher type 1/type 2 ratio at 7 ± 3 DIM compared with PLC cows (ASA = 0.062 ± 0.002; MEL = 0.064 ± 0.002; PLC = 0.056 ± 0.002). Regardless of treatment, there was an interaction between parity and day. Parous cows had higher type 1/type 2 ratios compared with nulliparous cows at 14 ± 3 d before calving and at 7 ± 3, 14 ± 3, and 21 ± 3 d after calving. Furthermore, there was a positive correlation between D2Dx scores at 14 ± 3 DIM and average daily milk yield in the first 60 DIM. These results suggest that prepartum anti-inflammatory therapies may cause an increased shift in type 1 immunity around calving. Similarly, parous cows may have an increased shift in type 1 immunity after calving. Interestingly, higher type 1/type 2 ratios may be associated with higher milk yields in the first 60 DIM. Larger studies are needed to identify associations between the D2Dx immunity test and cow health and performance, as well as to assess the applicability of these types of tests in a conventional farm setting.

Exploring vaginal discharge scoring to assess clinical metritis severity: Comparison between intrauterine dextrose and systemic antibiotics treatments.

The objectives of this study were to assess: 1) differences in the metabolic status, systemic inflammation, daily milk yield, and daily rumination time between Holstein dairy cows with different vaginal discharge scores (VDS) in the first 7±3 DIM, and 2) effects of intrauterine dextrose infusion on metabolic status, systemic inflammation, daily milk yield and daily rumination time in dairy cows with VDS4 and VDS5. Cows (n=641) from a farm located in central Pennsylvania were screened at 7±3 DIM (study d 0) to assess vaginal discharge scores. Vaginal discharge was scored using a five-point scale (i.e., 1- clear fluid, 2- <50% white purulent fluid, 3- >50% white purulent fluid, 4- red-brownish fluid without fetid smell, and 5- fetid red-brownish watery fluid). Cows with VDS4 and VDS5 were blocked by parity and randomly assigned to one of two treatment groups: 1) CONV (VDS4 n=15; VDS5 n= 23): two injections of ceftiofur (per label; 6.6 mg/Kg) 72 h apart; and 2) DEX (VDS4 n=15; VDS5 n=22): three intrauterine infusions of a 50% dextrose solution (1 L/cow) every 24 h. Cows that presented a VDS 1, 2, and 3 were categorized as normal vaginal discharge animals (NOMVDS; n=35) and were randomly selected and matched by parity to CONV and DEX cows. Daily milk yield and rumination time for the first 150 DIM were collected from on-farm computer records. Blood samples were collected to assess haptoglobin (HP) and ß-hydroxybutyrate (BHB) concentrations at study d 0, d 7, and d 14 relative to enrollment. Subclinical ketosis was defined as having a BHB concentration >1.2 mmol/dL at any of the sampling points. The data were analyzed using the MIXED and GLIMMIX procedures of SAS as a randomized complete block design. When comparing cows with different VDS (i.e., NOMVDS, VDS4, VDS5) separately, cows with VDS5 had the highest concentration of HP at enrollment compared to cows with VDS4 and NOMVDS; however, cows with VDS4 had higher concentrations of HP compared to cows with NOMVDS. Cows with VDS4 or VDS5 had a higher incidence of subclinical ketosis compared to cows with NOMVDS (p=0.005; VDS4= 62.08±9.16%; VDS5=74.44±6.74%; NOMVDS=34.36±8.53%). Similarly, daily milk yield (p<.0001; VDS4=30.17±1.32 kg/d; VDS5=27.40±1.27 kg/d; NOMVDS=35.14±1.35 kg/d) and daily rumination time (p=0.001; VDS4=490.77±19.44 min; VDS5=465±16.67 min; NOMVDS=558.29±18.80 min) was lower for cows with VDS4 and VDS5 compared to cows with NOMVDS at 7±3 days in milk. When analyzing HP concentration between treatment groups in cows with VDS4 (p=0.70), VDS5 (p=0.25), or VDS4 and VDS5 combined (p=0.31), there was no difference in HP concentration by study d 14 between treatment groups. Interestingly, when only cows with VDS4 were considered for treatment, both treatments, DEX and CONV, increased the daily milk yield to the levels of NOMVDS cows by 14 days in milk. On the other hand, when only cows with VDS5 were considered for treatment, cows treated with DEX produced, on average, 4.48 kg/d less milk in the first 150 days in milk compared to cows treated with CONV or cows that had NOMVDS. Similarly, when cows with either VDS4 or VDS5 were considered for treatment, DEX treatment also impaired milk yield. These results suggest that cows with either VDS 4 or 5 have an altered inflammatory status, and decreased milk yield and rumination compared to cows with NOMVDS. Furthermore, DEX treatment may have similar effects on daily milk yield and metabolic status compared to CONV in cows with VDS4, while DEX is not recommended for cows with VDS5.

The impact of beef sire breed on dystocia, stillbirth, gestation length, health, and lactation performance of cows that carry beef × dairy calves.

In the United States, it is becoming common for dairy herds to mate a portion of cows to beef semen to create a value-added calf. The objectives of this study were to determine if dystocia risk, stillbirth (SB) risk, gestation length (GL), probability of early-lactation clinical disease events, early-lactation culling risk, or subsequent milk production differ between cows that carried calves sired by different beef breeds and those that carried Holstein-sired calves. Records from 10 herds contained 75,256 lactations from 39,249 cows that had calves with known Holstein or beef breed sires from the years 2010 to 2023. Calf sire breeds with ≥150 records included in analyses were Holstein, Angus, Simmental, Limousin, crossbred beef, and Charolais. Additional beef sire breeds that existed in lower frequency (n < 150 records) were condensed together and classified as "other." Because GL is a continuous variable, sire breed inclusion criteria were reduced to n ≥ 100 records; thus, Wagyu sires were included as their own breed group. Some records did not contain all variables of interest, thus models included fewer lactations depending on variable. Binomial generalized mixed models evaluated dystocia risk (defined as calving ease score ≥4 or calving ease score ≥3), SB risk, clinical health event risk (defined as lameness, mastitis, metabolic, reproductive, other, or any health events occurring within 60 d in milk [DIM]), and early culling risk (defined as death or culling within 60 DIM). Gestation length and test-date milk, fat, and protein yields were evaluated with mixed models. Calves sired by crossbred beef bulls had a greater probability of being stillborn (5%; 95% confidence interval lower = 2.9% upper = 9.0%) than those sired by Holstein bulls (2%; 95% confidence interval lower = 1.5%, upper = 2.7%). All beef-sired calves increased GL from that of Holstein-sired calves (277 ± 0.15 d) with Limousin (282 ± 0.81 d) and Wagyu-sired calves (285 d ± 0.79) resulting in the longest GL. The risk of dystocia, clinical health events, and early-lactation culling did not differ by calf sire breed nor did subsequent milk and component yield. Generally, carrying a calf sired by the beef breeds included in this study did not negatively affect the dairy cow.

Postpartum intrauterine dextrose infusion: Effects on uterine health, metabolic stress, systemic inflammation, and daily milk yield in clinically healthy dairy cows.

The objective of this study was to assess the effect of intrauterine dextrose infusion at 4 ± 1 d in milk (DIM) on the incidence of clinical metritis (CM), metabolic stress [i.e., body condition score (BCS), ß-hydroxybutyrate (BHB) concentration, and subclinical ketosis incidence], systemic inflammation (i.e., haptoglobin concentration), and daily milk yield in clinically healthy postpartum dairy cows. Cows (n = 245) from a dairy farm located in southwest Pennsylvania were screened at 4 ± 1 DIM using a Metricheck (Simcro Tech Ltd.) device to assess vaginal discharge. In addition, overall cow health (e.g., lameness, abnormal breathing) and rectal temperature were assessed at this time. Cows (n = 134) that presented a clear dense vaginal discharge, were in clinically good health status, and had a normal rectal temperature (i.e., <39.7°C) were blocked by parity (primiparous = 64; multiparous = 70) and randomly assigned to 1 of 3 groups: (1) SAL (n = 45): 1 intrauterine infusion of isotonic saline solution (1 L/cow); (2) DEX (n = 44): 1 intrauterine infusion of a 50% dextrose solution (1 L/cow), or (3) CON (n = 45): cows remained untreated. Cows were re-screened at 7 d after enrollment (11 ± 1 DIM) using the Metricheck device to assess CM incidence (research clinical metritis incidence; RCMI). On-farm computer records (i.e., Dairycomp 305) were also used to collect clinical metritis incidence (farm clinical metritis incidence; FCMI). In addition, BCS was assessed and blood samples were collected at enrollment and at study d 7, 14, and 21. Furthermore, daily milk yield and clinical disease events for the first 60 DIM were collected from on-farm computer records. The data were analyzed using the MIXED and GLIMMIX procedures of SAS (SAS Institute Inc.) as a randomized complete block design. Although not significant, the RCMI and FCMI in DEX and SAL cows were on average 14.5 and 18.1 percentage points higher, respectively, compared with CON cows. The SAL cows had higher BHB and haptoglobin concentrations and higher incidence of subclinical ketosis compared with CON cows on study d 7. With regard to daily milk yield, there was a day by treatment interaction, where CON cows produced more milk on certain days compared with DEX and SAL cows. Based on these findings, authors conclude that intrauterine dextrose infusion in clinically healthy postpartum cows with normal vaginal discharge may be prejudicial for cow health and performance.

Effects of postpartum acetylsalicylic acid on uterine diseases and reproductive performance in dairy cattle.

Uterine diseases are some of the most prevalent and costly diseases for the dairy industry. It has been reported that an exacerbated and prolonged inflammatory response around calving can increase the risk of developing metritis, which subsequently can impair production and fertility in dairy cows. The objective of this study was to assess the effects of 2 oral administrations of acetylsalicylic acid 24 h apart on the incidence of uterine diseases [i.e., retained fetal membranes, clinical metritis, clinical endometritis) and reproductive performance [i.e., days in milk to conception, number of services to conception, proportion of cows pregnant at first service, proportion of abortion at first service (ABRT)] in dairy cows after calving. Cows from one dairy farm (n = 246) located in central Pennsylvania were included in this study. Animals were blocked by parity and randomly assigned to 1 of 2 groups: (1) ASA (n = 121): within ~12 h after parturition, cows received 2 treatments with acetylsalicylic acid (ASA; 200 mg/kg, 4 boluses) 24 h apart; or (2) UNT (n = 125): cows remained untreated. Clinical metritis was assessed at 7 ± 3 and 14 ± 3 d in milk (DIM) using a Metricheck device (Simcro Tech Ltd., Hamilton, New Zealand). Cows that presented a fetid, red-brownish, watery vaginal discharge were classified as having clinical metritis. Clinical endometritis was assessed through ultrasonography and defined as presence of hyperechoic fluid (>3 mm) in the uterus lumen at 50 ± 10 DIM. The incidence of retained fetal membranes was defined as the failure of expulsion of the placenta within 24 h after calving and recorded by farm personnel. The data were analyzed using the MIXED and GLIMMIX procedures of SAS (SAS Institute Inc., Cary, NC) as a randomized complete block design. A lower proportion of cows treated with acetylsalicylic acid developed clinical metritis at 7 ± 3 DIM (ASA = 34.97 ± 5.57%; UNT = 57.21 ± 5.80%) and tended to develop clinical endometritis at 50 ± 10 DIM (ASA = 3.84 ± 2.67%; UNT = 13.61 ± 5.23%) compared with cows that remained untreated. Cows treated with acetylsalicylic acid tended to require 18 d less to conceive compared with UNT cows (ASA = 125.63 ± 8.21 d; UNT = 143.44 ± 6.28 d). Furthermore, there was a tendency for a treatment × ABRT interaction, whereby ASA cows that aborted at first service tended to conceive 35 d sooner compared with UNT cows that aborted at first service (ASA = 151.42 ± 15.90 d; UNT = 186.38 ± 11.84 d). Although there was no difference in pregnancy per AI at first service between treatment groups (ASA = 23.88 ± 7.92%; UNT = 17.93 ± 6.31%), the proportion of cows aborting at first service in the ASA group tended to be lower than that in the UNT group (ASA = 1.03 ± 1.06%; UNT = 6.04 ± 2.62%). Results from this study suggest that a short-duration acetylsalicylic acid treatment after calving may decrease the incidence of uterine diseases and improve reproductive success in cows that aborted at first service in dairy cattle.

Association of prepartum lying time with nonesterified fatty acids and stillbirth in prepartum dairy heifers and cows.

The objective of the present study was to assess the association of prepartum lying time (LT) and the coefficient of variation (CV) of LT within 7 d before calving with prepartum serum nonesterified fatty acid (NEFA) concentration at 7 ± 3 d prepartum (dpp) and stillbirth. Prepartum pregnant Holstein heifers and cows from 3 dairy herds were used (n = 1,044). Animals were housed in freestall barns using a prepartum pen 21 d before the expected calving date and were moved into a contiguous maternity pen at parturition. Monthly, cohorts of 20 to 36 animals (heifers and cows combined) were enrolled at each farm and electronic data loggers (IceQube, IceRobotics, Edinburgh, UK) were fitted to the hind leg of individual animals to assess their behavioral activity. Stillbirth was defined as a calf born dead or died during the first 24 h after parturition in dams with normal gestation length. The LT was recorded for the last 7 dpp to assess differences among dams with stillbirth versus those with a calf born alive. Mean LT within 7 d before blood NEFA collection was assessed to determine the association with prepartum serum NEFA at 7 ± 3 dpp. Blood samples for the assessment of serum NEFA concentration were collected from prepartum animals at 14 ± 3 and at 7 ± 3 dpp. Blood samples for total serum calcium concentration were collected from postpartum cows within 48 h after parturition to assess differences among cows with stillbirth versus those with a calf born alive. Data were analyzed using CORR, MIXED, or GLIMMIX procedures of SAS (SAS Institute Inc., Cary, NC). Dams experiencing dystocic births had a greater proportion of stillbirth, but herd, parity, and season did not have an effect. Dams with a stillborn calf had reduced LT and increased CV of LT within the last 7 dpp compared with dams with a calf born alive, regardless of parity. Multiparous cows with a stillborn calf had higher prepartum serum NEFA concentration compared with multiparous cows with a calf born alive, but this did not differ for first-calf heifers. Regardless of parity, the proportion of postpartum cows with hypocalcemia was higher for dams with a stillborn calf compared with those with a calf born alive. Regardless of parity, LT of prepartum dams was strongly correlated with the CV of LT (as LT increased, the CV decreased), and prepartum dams with a mean LT between 11 and 15 h/d had the lowest serum NEFA concentration compared with dams with LT of 8 to 10 or >16 h/d. Serum NEFA concentrations at 7 ± 3 dpp was positively correlated with the CV of LT within 7 d before blood sample. These results show that the dam's prepartum LT and its consistency over time are associated with prepartum serum NEFA and calf survival at calving.

Administration of acetylsalicylic acid after parturition in lactating dairy cows under certified organic management: Part I. Milk yield, milk components, activity patterns, fertility, and health.

Parturition is a natural process that gradually progresses from one stage to the next. However, around 5% of dairy cows will experience dystocia, which is considered to be a painful and stressful event. Studies have reported positive effects on cow performance and welfare after treatment with nonsteroidal anti-inflammatory drugs during the first postpartum days. The objectives were to assess the effects of acetylsalicylic acid administration after calving on (1) milk yield and components, (2) daily activity patterns, (3) reproductive performance, and (4) health in lactating dairy cows under certified organic management. Cows from 3 organic herds were enrolled. Within 12 h after parturition, cows were blocked by parity and calving ease and randomly assigned to 2 treatments: (1) aspirin (ASP; n = 278), in which cows received 4 consecutive treatments every 12 h with acetylsalicylic acid (100 mg/kg; 2 boluses) or (2) placebo (PLC, n = 285), in which cows received 4 treatments every 12 h with gelatin capsules (2 capsules) filled with water. Daily milk yield for the first 30 d in milk (DIM) and monthly milk yield, fat, protein, and somatic cell count (SCC) data from the first 5 Dairy Herd Improvement Association tests were collected. Activity patterns were measured using activity data loggers in the first 7 DIM. Clinical disease events (60 DIM) and fertility data were collected from on-farm computer records. Statistical analysis was performed using the MIXED (milk yield, components, and activity), LIFETEST (fertility), and GLIMMIX (health) procedures of SAS (SAS Institute Inc., Cary, NC). Overall, ASP cows produced 1.82 kg/d more milk than PLC cows during the first 30 DIM. Interestingly, cows that experienced dystocia and received ASP produced 4.48 kg/d more milk compared with cows in the PLC group that experienced dystocia. Cows treated with ASP had lower somatic cell count during the first 5 Dairy Herd Improvement Association tests. There were no differences in daily lying time, lying bouts, and lying bout duration between the ASP and PLC groups. However, cows in the ASP group had 587,64 steps/d more compared with PLC cows. In addition, ASP cows tended to require fewer days (ASP = 113.76 ± 4.99 d; PLC = 125.36 ± 4.74 d) and needed fewer services (ASP = 1.86 ± 0.21 services; PLC = 2.19 ± 0.24 services) to become pregnant compared with PLC cows. There were no differences in clinical disease events between treatments. Results from this study suggest that treating cows with ASP after calving may help improve milk yields and udder health, increase activity, and enhance fertility in dairy cattle under certified organic management.

Administration of acetylsalicylic acid after parturition in lactating dairy cows under certified organic management: Part II. Biomarkers of nociception, inflammation, and stress.

The objective was to assess the effect of oral administration of acetylsalicylic acid after calving on the concentrations of substance P (SP), haptoglobin (HP), and cortisol in lactating dairy cows. Holstein dairy cows (n = 152) from 3 organic herds were included. At parturition, cows were blocked by parity [multiparous (MULT) and primiparous (PRIM)] and calving ease [eutocia (EUT) and dystocia (DYS)] and were randomly assigned to 1 of 2 treatment groups: aspirin (ASP; n = 76), in which within 12 h after parturition cows received 4 treatments with acetylsalicylic acid (100 mg/kg; 2 boluses) at 12-h intervals, or placebo (PLC; n = 76), in which within 12 h after parturition cows received 4 consecutive treatments with gelatin capsules (2 capsules) containing water 12 h apart. Blood samples were collected immediately before treatment and at 12, 24, 36, 48, and 168 h (7 DIM) for assessment of circulating concentration of SP, HP, and cortisol. Based on farm records, cows were classified in the following clinical disease categories: no clinical disease event (NO-EVT), a single clinical disease event (SI-EVT), and more than 1 clinical disease event (MU-EVT). The study data were analyzed as a randomized complete block design using mixed multiple linear and logistic regression models. With regard to HP, there was a tendency for an interaction between treatment and parity, where MULT cows treated with ASP had lower concentration of HP compared with MULT cows treated with PLC (ASP = 124.33 ± 6.83 µg/mL; PLC = 143.9 ± 7.24 µg/mL). Analysis by calving ease showed that cows with DYS had higher concentrations of HP (DYS = 159.17 ± 5.97 µg/mL; EUT = 138.72 ± 6.22 µg/mL) and SP (only at 168 h; DYS = 64.99 pg/mL, 95% confidence interval, CI: 2.68-2.81; EUT = 60.33 pg/mL, 95% CI: 2.91-3.06) after calving compared with EUT cows. Regardless of treatment, PRIM cows had higher concentrations of SP (MULT = 55.11 pg/mL, 95% CI: 1.27-1.30; PRIM = 57.62 pg/mL, 95% CI: 1.99-2.06), HP (MULT = 134.14 ± 4.96 µg/mL; PRIM = 163.75 ± 7.76 µg/mL), and cortisol (MULT = 18.65 µg/mL, 95% CI: 1.02-1.05; PRIM = 21.92 µg/mL, 95% CI: 1.67-1.74) compared with MULT cows. In addition, cows that experienced SI-EVT or MU-EVT had higher concentrations of HP (NO-EVT = 134.13 ± 5.95 µg/mL; SI-EVT = 142.68 ± 7.32 µg/mL; MU-EVT = 170.03 ± 9.42 µg/mL) and cortisol (NO-EVT = 17.86 µg/mL, 95% CI: 1.20-1.24; SI-EVT = 21.01 µg/mL, 95% CI: 1.61-1.67; MU-EVT = 22.01 µg/mL, 95% CI: 2.08-2.18) compared with cows with NO-EVT recorded. Results from this study suggest that a short-duration anti-inflammatory therapy after calving reduced HP in MULT cows but may not have effects on SP and cortisol concentrations. Calving ease and parity affected the concentrations of markers of inflammation, nociception, and stress regardless of treatment. Further research is warranted to assess anti-inflammatory strategies aimed at decreasing inflammation and stress in DYS and PRIM cows and therefore improve welfare and performance of these high-priority groups.

Effects of postpartum acetylsalicylic acid on metabolic status, health, and production in lactating dairy cattle.

The transition period is one of the most challenging times for dairy cattle. Previous research suggests that treatment of postpartum cows with anti-inflammatory drugs may decrease pain and inflammation, enhancing cow welfare and performance during this challenging period. However, these strategies involve numerous time-consuming interventions, which require extra labor and do not fit modern farm logistics. The objective of this experiment was to assess the effects of acetylsalicylic acid (ASA) every 24 h for 2 d after calving on (1) daily milk yield, daily milk conductivity, and daily rumination during the first 60 days in milk (DIM), and 305-d mature-equivalent milk, milk fat, and milk protein yields, (2) body condition score, ß-hydroxybutyrate (BHB), and haptoglobin, and (3) incidence of clinical diseases during the first 60 DIM. Dairy cows (n = 246) from a dairy farm located in Pennsylvania were enrolled in this experiment. Cows were blocked by parity and assigned randomly to 1 of 2 treatments: (1) ASA (n = 121), in which cows received 2 treatments with ASA (200 mg/kg; 4 boluses), the first within 12 h after parturition and the second 24 h later; or (2) untreated (UNT; n = 125), in which cows remained untreated. Blood samples were collected at 30 ± 6 h, 7 ± 3 d, and 14 ± 3 d after calving to measure BHB and haptoglobin concentrations. Body condition score was assessed at enrollment, 7 ± 3 DIM, 14 ± 3 DIM, and 50 ± 10 DIM. Furthermore, incidences of diseases, daily rumination, daily milk yield, and daily milk conductivity during the first 60 DIM and 305-d mature-equivalent milk, milk fat, and milk protein yields were collected from on-farm computer records. The data were analyzed using mixed multiple linear and logistic regression models as a randomized complete block design. Multiparous cows treated with ASA produced 1.64 kg/d more milk compared with multiparous cows that remained untreated (ASA = 41.66 ± 0.88 kg/d; UNT = 40.02 ± 0.81 kg/d) during the first 60 DIM. There was no difference in daily milk conductivity and rumination between treatments. Cows treated with ASA had lower concentration of BHB (ASA = 1.16 ± 0.64 mmol/L; UNT = 1.23 ± 0.80 mmol/L) during the first 14 ± 3 DIM and had higher body condition score within the first 50 ± 10 DIM compared with cows that remained UNT. There were no differences in circulating concentrations of haptoglobin between treatments. These results support previous findings showing that the use of anti-inflammatory drugs after calving may increase milk production and affect the metabolic status of dairy cows.

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.

Associations of pre- and postpartum lying time with metabolic, inflammation, and health status of lactating dairy cows.

The objective was to evaluate the associations of pre- and postpartum lying time (LT) with serum total calcium (Ca), nonesterified fatty acids (NEFA), ß-hydroxybutyrate (BHB), and haptoglobin concentrations, hemogram, and health status of dairy cows. A total of 1,052 Holstein cattle (401 nulliparous heifers and 651 parous cows) from 3 commercial dairy farms were fitted with electronic data loggers (IceQube, IceRobotics, Edinburgh, UK) on a hind leg 14 ± 3 d before parturition (dpp) and removed at 14 ± 3 d in milk (DIM) to assess their LT. Lying time data were summarized and reported daily (min/d or h/d). Serum concentrations of NEFA (at 14 ± 3 and 7 ± 3 dpp), total serum calcium within 48 h after calving, and BHB (at 7 ± 3 and 14 ± 3 DIM) were determined. Serum concentration of haptoglobin was determined and a hemogram was performed on a subsample of 577 cows (237 primiparous and 340 multiparous) at 7 ± 3 DIM. Cases of milk fever, retained placenta, metritis, mastitis, pneumonia, and digestive disorders within 30 DIM were recorded and cows were categorized into 1 of 4 groups: (1) nondiseased (ND, n = 613; cows without ketosis and any other health conditions); (2) cows with only ketosis (KET, n = 152); (3) sick cows experiencing ≥1 health conditions, but without ketosis (SICK, n = 198); or (4) cows with ketosis plus at least one other health condition (KET+, n = 61). Data were analyzed using mixed linear regression models or logistic regression (MIXED or GLIMMIX procedures). Lying time within 14 dpp had a significant positive quadratic association with serum NEFA concentrations at 14 ± 3 and 7 ± 3 dpp but was not significantly associated with serum Ca concentration within 48 h after calving. Lying time during the first 14 DIM after parturition had a significant linear association with the risk of ketosis within 14 DIM. For every 1-h increment in mean LT (from 8 to 15 h/d) within the first 14 DIM after calving, the risk of diagnosis with ketosis within 14 DIM increased by 3.7 percentage points. Regardless of parity, a greater proportion of KET and KET+ groups had increased serum prepartum NEFA concentration (≥400 µEq/L) and increased body condition loss from 14 dpp to 28 DIM compared with SICK and ND cows. A greater proportion of multiparous KET and KET+ cows had hypocalcemia within 48 h after calving compared with ND and SICK cows, but we did not detect a significant association between hypocalcemia and health status on primiparous cows. Multiparous KET+ cows had significantly reduced neutrophils and white blood cell count compared with ND cows, but lymphocytes did not differ. Regardless of parity, KET+ and SICK cows had significantly higher concentrations of serum haptoglobin compared with ND cows. These results suggest that LT along with energy and Ca balance are critical for transition cow health.

Associations of postpartum lying time with culling, milk yield, cyclicity, and reproductive performance of lactating dairy cows.

The objectives were to evaluate the associations of lying time (LT) during the first 14 d in milk (DIM) with milk yield, cyclicity (CYC), culling within 60 DIM (CULL), and reproductive performance of lactating dairy cows. A total of 1,052 Holstein cattle (401 nulliparous heifers and 651 parous cows) from 3 commercial dairy farms had electronic data loggers (IceQube, IceRobotics, Edinburgh, UK) placed on a hind leg 14 ± 3 d before the expected parturition date and removed at 14 ± 3 DIM to assess their LT. Serum concentrations of ß-hydroxybutyrate were determined at 7 ± 3 and 14 ± 3 DIM. Cases of retained placenta, metritis, mastitis, pneumonia, and digestive disorders within 30 DIM were recorded and lactating cows were categorized into 1 of 4 groups: (1) nondiseased (ND, n = 613; cows without ketosis or any other diagnosed health condition); (2) cows with only ketosis (KET, n = 152); (3) sick cows experiencing ≥1 health conditions but without ketosis (SICK, n = 198); or (4) cows with ketosis plus ≥1 health condition (KET+, n = 61). Ultrasound was performed at 28 ± 3 and 42 ± 3 DIM to assess ovarian cyclicity (presence or absence of corpus luteum). Milk yield at first Dairy Herd Improvement Association test was not associated with LT during the first 14 DIM, but it was negatively correlated with the coefficient of variation of LT during the first 14 DIM. Lactating dairy cows experiencing KET+ had the lowest milk yield compared with ND, regardless of parity. Parity, health status, and season were significantly associated with CYC and CULL. Lying time had a significantly linear association with the risk of being culled: for every 1-h increment of LT during 0 to 14 DIM, the risk of culling within 60 DIM increased by 1 percentage point. Lying time had a negative quadratic association with cyclicity at 42 DIM. Multiparous cows with a LT of 9 to 13 h/d had a significantly greater probability of pregnancy up to 300 DIM compared with cows with a LT >13 h/d. Regardless of parity, KET+ cows had significantly higher proportion of culling within 60 DIM and decreased probability of pregnancy up to 300 DIM compared with ND cows. These findings suggest that there is an optimum daily LT range for early postpartum cows housed in freestall barns, different from that reported for mid-lactation cows, with the potential for improved survival, health, and the overall performance (milk yield and reproduction).

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.

Assessment of an application for touchscreen devices to record calving-related events in dairy herds and monitor personnel performance.

The objectives of the present study were to assess (1) the effectiveness of a calving training workshop and an application (app) for touchscreen devices to capture calving-related events, and (2) personnel compliance with calving protocols (time from birth to feeding of first colostrum and time that cows spent in labor). Calving personnel (n=23) from 5 large dairy farms (range: 800-10,000 cows) participated in the study. Participants received training through an on-farm workshop regarding calving management practices and functioning of the app before recording calving-related events. Pre- and posttest evaluations were administered to each participant to measure their knowledge gain and satisfaction with the workshop. Calving personnel recorded calving-related events (n=323) using the app for 7 d following training. Furthermore, the records collected with the app were used to assess missing and incorrect data and calving personnel compliance with calving management protocols (recording time that cows spent in labor and timing of feeding first colostrum to calves). Calving personnel reported that the information provided during the training was relevant (agree=14.3% and strongly agree=85.7%) and of great immediate use (agree=33.3% and strongly agree=66.7%). The presented materials and hands-on demonstrations substantially increased the knowledge level of the attendees (by 23.7 percentage points from pre- to posttest scores). The follow-up assessment with participants revealed that the app was easy to use (91.3%) and that they would continue to use it (100%). Frequency of incorrect (r=0.77) or missing (r=0.76) data was positively correlated with calving:personnel ratio. Furthermore, calving personnel compliance with calving protocols was significantly different within and between herds. These results substantiated the great variation in compliance with calving management protocols within and between dairy farms. Furthermore, the app may serve as a tool to monitor personnel compliance with first feeding of colostrum to calves and their awareness and recognition of amount of time that each cow spent in labor. This would allow decision-makers to adjust, reassign tasks, or plan the management according to actual calving rate to improve the overall quality of data (frequency of incorrect and missing data) and calf welfare (survival and performance).

Effect of intrauterine dextrose on reproductive performance of lactating dairy cows diagnosed with purulent vaginal discharge under certified organic management.

The objectives of the study were to assess responses to treatments (clinical cure and resumption of estrous cycles) of cows with purulent vaginal discharge (PVD) that received intrauterine infusion of a hypertonic solution of 50% dextrose (DEX) or untreated control (CON) cows and the subsequent pregnancy per artificial insemination (PAI) in cows with and without PVD. Cows (n=2,852) from 2 dairy herds were screened for PVD using the gloved hand technique at exam 1 [26±3 d in milk (DIM)]. Cows with vaginal discharge scores of 2 or 3 (0-3 scale) were stratified by parity and randomly allocated into 1 of 2 treatment groups: (1) intrauterine infusion (~200 mL) of 50% DEX solution (n=456), or (2) untreated control animals (CON, n=491). Fourteen days posttherapy (40±3 DIM), cows with PVD were re-examined at exam 2 (40±3 DIM) to assess the response to treatments. All cows were subjected to the same reproductive program, which consisted of estrus detection twice daily (using tail chalking and visual observation) for the first 5 artificial inseminations; then, open lactating cows were turned out with bulls. Cows displaying signs of standing estrus underwent AI and no reproductive hormones were used. Pregnancy diagnosis (PD) was performed via transrectal palpation at 40±3 d post-AI. The risk of culling within 14 d posttherapy was not different among treatment groups. Cows with PVD had greater cervical diameter at exam 1 and decreased PAI compared with cows without PVD. Treatment with DEX increased the proportion of cows with clear vaginal discharge (clinical cure) and cyclicity 14 d posttherapy compared with CON cows. Pregnancy per AI for DEX (29.2±2%) cows was significantly greater than that for CON (22.5±2%) cows. Cows without PVD had a greater proportion of cycling cows (65.6%) and PAI (37%) with reduced pregnancy losses (5.7%) compared with DEX or CON cows. The use of intrauterine DEX alone improved reproductive performance of cows with PVD.