Evaluating differences in milk production, reproductive performance, and survival associated with vaginal discharge characteristics and fever in postpartum dairy cows

The objective was to assess differences in productive and reproductive performance, and survival associated with vaginal discharge characteristics and fever in postpartum dairy cows located in Western and Southern states of the U.S.A. This retrospective cohort study included data from 3 experiments conducted in 9 dairies. Vaginal discharge was evaluated twice within 12 DIM and scored on a 5-point scale. The highest score observed for each cow was used for group assignment (VD group) as follows: VD 1 and 2 (VD 1/2; n = 1,174) = clear mucus/lochia with or without flecks of pus; VD 3 (n = 1,802) = mucopurulent with < 50% pus; VD 4 (n = 1,643) = mucopurulent with ≥50% of pus or non-fetid reddish/brownish mucous, n = 1,643; VD 5 = fetid, watery, and reddish/brownish, n = 1,800. All VD 5 cows received treatment according to each herd's protocol. Rectal temperature was assessed in a subset of VD 5 cows, and subsequently divided into Fever (rectal temperature ≥39.5°C; n = 334) and NoFever (n = 558) groups. A smaller proportion of cows with VD 5 (67.6%) resumed ovarian cyclicity compared with VD 1/2 (76.2%) and VD 4 (72.9%) cows; however, a similar proportion of VD5 and VD 3 (72.6%) cows resumed ovarian cyclicity. A smaller proportion of VD 5 (85.8%) cows received at least one artificial insemination (AI) compared with VD 1/2 (91.5%), VD 3 (91.0%), or VD 4 (91.6%) cows. Although we did not detect differences in pregnancy at first AI according to VD, fewer cows with VD 5 (64.4%) were pregnant at 300 DIM than cows with VD 1/2 (76.5%), VD 3 (76.2%), or VD 4 (74.7%). Hazard of pregnancy by 300 DIM was smaller for VD 5 compared with VD 1/2, VD 3, or VD 4 cows. A greater proportion of VD 5 cows were removed from the herd within 300 DIM compared with other VD groups. There was 760 kg lesser milk production within 300 DIM for VD 5 compared with VD 2, VD 3, and VD 4, whereas VD 2, VD 3, and VD 4 had similar milk production. We did not detect an association between fever at diagnosis of VD 5 and reproductive performance or milk production. A greater proportion of VD 5 cows without fever were removed from the herd by 300 DIM compared with VD 5 cows with fever. Differences in productive and reproductive performance, and removal of the herd were restricted to fetid, watery, and reddish/brownish vaginal discharge, which was independent of fever.

Validation of the Unesp-Botucatu pig composite acute pain scale (UPAPS) in piglets undergoing castration

To accurately assess pain and support broadly-based analgesic protocols to mitigate swine pain, it is imperative to develop and validate a species-specific pain scale. The objective of this study was to investigate the clinical validity and reliability of an acute pain scale (UPAPS) adapted for newborn piglets undergoing castration. Thirty-nine male piglets (five days of age, 1.62 ± 0.23 kg BW) served as their own control, were enrolled in the study and underwent castration in conjunction with an injectable analgesic administered one-hour post-castration (flunixin meglumine 2.2 mg/kg IM). An additional 10, non-painful female piglets were included to account for the effect of natural behavioral variation by day on pain scale results. Behavior of each piglet was video recorded continuously at four recording periods (24 h pre-castration, 15 min post-castration, 3 and 24 h post-castration). Pre- and post-operative pain was assessed by using a 4-point scale (score 0-3) including the following six behavioral items: posture, interaction and interest in surroundings, activity, attention to the affected area, nursing, and miscellaneous behavior. Behavior was assessed by two trained blinded observers and statistical analysis was performed using R software. Inter-observer agreement was very good (ICC = 0.81). The scale was unidimensional based on the principal component analysis, all items except for nursing were representative (rs ≥ 0.74) and had excellent internal consistency (Cronbach's alpha ≥ 0.85). The sum of scores were higher in castrated piglets post-procedure compared to pre-procedure, and higher than in non-painful female piglets confirming responsiveness and construct validity, respectively. Scale sensitivity was good when piglets were awake (92.9%) and specificity was moderate (78.6%). The scale had excellent discriminatory ability (area under the curve > 0.92) and the optimal cut-off sum for analgesia was 4 out of 15. The UPAPS scale is a valid and reliable clinical tool to assess acute pain in castrated pre-weaned piglets.

Failure of clinical cure in dairy cows treated for metritis is associated with reduced productive and reproductive performance

Objectives were to assess reproductive and productive outcomes associated with failure of clinical cure in dairy cows diagnosed with metritis following antimicrobial therapy. This retrospective cohort study included data from 3 experiments performed in 5 dairies. Metritis was characterized by the presence of watery, fetid, reddish-brownish vaginal discharge within 21 DIM (study d 0). Cows not diagnosed with metritis (i.e., cows may have had other diseases postpartum; NoMT; n = 1,194) were paired based on lactation number and calving date. All cows with metritis received antimicrobial therapy (ampicillin or ceftiofur). Clinical cure was evaluated on d 10 based on vaginal discharge score, and cows were categorized as cured (MTC; n = 1,111) or not cured (MTnoC; n = 299). Purulent vaginal discharge (28 ± 3 or 32 ± 3 DIM), cytological endometritis (35 ± 3 or 39 ± 3 DIM), and estrous cyclicity (50 ± 3 and 64 ± 3, 36 ± 3 and 50 ± 3, or 37 ± 5 and 51 ± 5 DIM) were evaluated in subgroups of cows. Proportions of cows with purulent vaginal discharge and cytological endometritis were greatest for MTnoC (91.7 and 91.4%), intermediate for MTC (74.0 and 73.3%), and smallest for NoMT (38.1 and 36.4%). Proportion of cyclic cows was smaller for MTnoC compared with MTC and NoMT (62.0, 71.0, and 71.0%). Pregnancy per artificial insemination following first service was smaller for cows with metritis compared with their counterparts with no metritis (NoMT = 28.1, MTC = 26.1, MTnoC = 22.0%). Pregnancy loss tended to be greater for MTnoC compared with MTC (NoMT = 11.5, MTC = 11.1, MTnoC = 18.4%). Hazard of pregnancy by 300 DIM was smallest for MTnoC, intermediate for MTC, and greatest for NoMT. Death by 60 DIM (3.9, 1.1, and 0.6%) and removal from herd by 300 DIM (26.3, 17.4, and 15.4%) were greatest for MTnoC compared with MTC and NoMT, respectively. Milk production among multiparous cows was smaller for MTnoC compared with MTC and NoMT in the first 10 mo postpartum, whereas MTC produced less milk compared with NoMT only during the first 2 mo postpartum (NoMT = 42.0 ± 0.22, MTC = 40.6 ± 0.28, MTnoC = 37.7 ± 0.54 kg/d). Failure of clinical cure was not associated with milk yield in primiparous cows (NoMT = 35.2 ± 0.31, MTC = 33.9 ± 0.31, MTnoC = 35.0 ± 0.52 kg/d). Cows diagnosed with metritis that do not undergo clinical cure by 10 d of onset of antimicrobial therapy have impaired reproductive performance, reduced milk production, and increased risk of leaving the herd.

Effects of metritis treatment strategies on health, behavior, reproductive, and productive responses of Holstein cows

Our objectives were to compare the effects of ceftiofur crystalline free acid (CCFA) and ampicillin trihydrate (AMP) treatments of cows diagnosed with metritis on uterine health, behavior, reproductive, and productive responses. A controlled randomized clinical trial was designed. Metritis was defined as vaginal discharge (VD) = 5 (fetid, watery, red/brown) within 21 d in milk (DIM) and rectal temperature (RT) <39.5°C, whereas VD = 5 and RT ≥39.5°C was defined as puerperal metritis. On the day of diagnosis (d 0), cows were paired by parity and severity of metritis (metritis vs. puerperal metritis) and assigned randomly to the AMP and CCFA treatments. Cows enrolled in the AMP (n = 308) treatment were moved to a nonsalable-milk pen, where they were treated once daily for 5 d, and were moved back to their original pen 72 h after the last treatment (d 7). Cows enrolled in the CCFA (n = 310) treatment remained in their original pen and received 2 treatments of CCFA, 72 h apart. Rectal temperature was measured daily from d 0 to 6 and on d 11. Vaginal discharge was evaluated on d 4, 6, and 11 to assess cure. Cure was defined as the absence of treatment with additional antimicrobial before experiment d 11, VD <5, and RT <39.5°C. Cows were examined at 28 ± 3 DIM for purulent VD (PVD) and at 35 ± 3 DIM for cytological endometritis. Pregnancy was diagnosed at 40 ± 3 and 60 ± 7 d after first and second artificial inseminations. Cure of metritis did not differ between treatments on d 11 (AMP = 64.6 ± 3.1, CCFA = 63.5 ± 3.1%). Cows treated with AMP had greater RT from experiment d 1 to 6 compared with cows treated with CCFA (AMP = 39.1 ± 0.02, CCFA = 39.0 ± 0.02°C). Cows in the AMP treatment had greater prevalence of PVD at 28 ± 3 DIM (AMP = 82.6 ± 2.3, CCFA = 74.4 ± 2.7%) and tended to have greater prevalence of cytological endometritis at 35 ± 3 DIM (AMP = 77.8 ± 6.2 vs. CCFA = 61.7 ± 7.5%) than CCFA-treated cows. Treatment did not affect the hazard of pregnancy among multiparous cows; however, among primiparous cows, CCFA treatment reduced the hazard of pregnancy and increased the median days to pregnancy (AMP = 145 vs. CCFA = 169 d). Finally, average daily milk yield up to 14 wk postpartum was not affected by treatment (AMP = 38.0 ± 0.4, CCFA = 37.5 ± 0.4 kg). We conclude from the current experiment that CCFA was more effective in reducing RT and improving uterine health of metritic cows; however, the improved hazard of pregnancy of primiparous cows treated with AMP is important and warrants further investigation.

Use of on-farm milk progesterone information to predict fertility outcomes in dairy cows subjected to timed artificial insemination

The objectives of this study were to evaluate the use of a qualitative on-farm milk progesterone test to predict non-pregnancy in dairy cows. Lactating Jersey cows (n = 752) were subjected to the 5-d Cosynch-72 protocol for timed artificial insemination (AI; d -8 GnRH, d -3 and -2 PGF_2α, d 0 GnRH and timed AI). Milk was sampled on d -3, 0, 7, and 28 relative to timed AI, and progesterone concentrations were assessed using a lateral flow immunochromatographic test. Samples were classified into 3 groups indicative of high (hP4; test line not visible or lighter than reference), intermediate (iP4; test line similar to reference), and low (lP4; test line darker than reference) progesterone concentrations. Blood was sampled from a subset of cows (n = 50) on d -3, 0, 7, and 28 relative to timed AI, and plasma progesterone concentrations were determined by RIA. Cows were observed daily for signs of estrus based on removal of tail paint. Pregnancy was diagnosed by ultrasonography on d 34 and 62 after AI. Plasma progesterone concentrations across all time points were greater for hP4 (3.13 ± 0.20 ng/mL) followed by iP4 (1.12 ± 0.27 ng/mL) and lP4 (0.38 ± 0.23 ng/mL). Cows in lP4 on d -3 had lesser pregnancy per AI (P/AI) compared with iP4 and hP4 (17.4, 38.3, and 37.2%, respectively). For measurements performed on the day of AI (d 0), lP4 cows had greater P/AI compared with hP4 and iP4 (34.8, 0.0, and 15.6%, respectively), and the risk of pregnancy loss tended to be greater for iP4 compared with lP4. Cows in lP4 on d 7 after AI had lesser P/AI than those in iP4 and hP4 (12.0, 34.0, and 37.7%, respectively). Cows classified as lP4 on d 28 had the least P/AI on d 62 followed by iP4 and then hP4 (0.8, 9.2, and 59.4%, respectively) and were at the greatest risk for pregnancy loss (lP4 = 74.6%, iP4 = 8.4%, hP4 = 7.1%). Sensitivity and specificity to predict non-pregnancy on d 62 were 0.86 and 0.32 (d -3), 0.95 and 0.15 (d 0), 0.93 and 0.23 (d 7), and 0.99 and 0.53 (d 28), respectively. On-farm milk progesterone profiling using a lateral flow immunochromatographic test was able to identify cows without functional corpus luteum and to predict fertility outcomes following timed AI.