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.

The economic cost of metritis in dairy herds.

The objective of this study was to estimate the cost of metritis in dairy herds. Data from 11,733 dairy cows from 16 different farms located in 4 different regions of the United States were compiled for up to 305 d in milk, and 11,581 cows (2,907 with and 8,674 without metritis) were used for this study. Metritis was defined as fetid, watery, red-brownish vaginal discharge that occurs ≤21 d in milk. Continuous outcomes such as 305-d milk production, milk sales ($/cow), cow sales ($/cow), metritis treatment costs ($/cow), replacement costs ($/cow), reproduction costs ($/cow), feeding costs ($/cow), and gross profit per cow ($/cow) were analyzed using mixed effect models using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC). Gross profit was also compared using the Kruskal-Wallis test. Dichotomous outcomes such as pregnant and culling by 305 d in milk were analyzed using the GLIMMIX procedure of SAS. Time to pregnancy and culling were analyzed using the PHREG procedure of SAS. Models included the fixed effects of metritis, parity, and the interaction between metritis and parity, and farm as the random effect. Variables were considered significant when P ≤ 0.05. Metritis cost was calculated by subtracting the gross profit of cows with metritis from the gross profit of cows without metritis. A stochastic analysis was performed with 10,000 iterations using the observed results from each group. Milk yield and proportion of cows pregnant were lesser for cows with metritis than for cows without metritis, whereas the proportion of cows leaving the herd was greater for cows with metritis than for cows without metritis. Milk sales, feeding costs, residual cow value, and gross profit were lesser for cows with metritis than for cows without metritis. Cow sales and replacement costs were greater for cows with metritis than for cows without metritis. The mean cost of metritis from the study herds was $511 and the median was $398. The stochastic analysis showed that the mean cost of a case of metritis was $513, with 95% of the scenarios ranging from $240 to $884, and that milk price, treatment cost, replacement cost, and feed cost explained 59%, 19%, 12%, and 7%, respectively, of the total variation in cash flow differences. In conclusion, metritis caused large economic losses to dairy herds by decreasing milk production, reproduction, and survival in the herd.

Economic comparison between ceftiofur-treated and nontreated dairy cows with metritis.

The objective was to investigate the economic effect of treating dairy cows with metritis using ceftiofur-free acid or leaving them untreated at the time of diagnosis. Cows with a fetid, watery, red-brownish vaginal discharge were diagnosed with metritis (d 0). Data from 875 dairy cows (506 primiparous and 369 multiparous) from 1 herd in northern Florida that had been part of a larger study evaluating different treatments for metritis were used for the economic analysis. Holstein cows with metritis had been randomly assigned to: Ceftiofur (CEF, n = 239) = subcutaneous injection of 6.6 mg/kg of ceftiofur crystalline-free acid in the base of the ear at d 0 and d 3; Untreated (UNT, n = 233) = no treatment applied at metritis diagnosis. Both groups could receive escape therapy if condition worsened. A group of nonmetritic healthy cows (NMET; n = 403) from the same cohort was randomly selected for comparison. Continuous outcomes such as 300-d milk production (kg/cow), milk sales ($/cow), cow sales ($/cow), treatment cost by 60 days in milk ($/cow), reproduction cost ($/cow), replacement cost ($/cow), feeding cost ($/cow), and gross profit per cow ($/cow) were analyzed using the ANOVA (MIXED procedure of SAS version 9.4). Dichotomous outcomes such as pregnancy and culling by 300 d were analyzed using logistic regression (GLIMMIX procedure of SAS). Models included the fixed effects of treatment, parity, and the interaction between treatment and parity. A stochastic analysis was performed with 10,000 iterations using the observed results from each group. The CEF treatment resulted in greater treatment cost by 60 DIM than UNT ($112 vs. $37), but resulted in a greater proportion of pregnant cows (71 vs. 61%) and decreased culling by 300 DIM (29 vs. 39%) compared with UNT. Gross profit was lesser for UNT than NMET ($2,969 vs. $3,426), and CEF was intermediate ($3,219). The stochastic analysis showed that the mean difference in gross profit between UNT and NMET was -$457; saleable milk (49%) and replacement cost (24%) accounted for most of the variation. The mean difference in gross profit between CEF and NMET group was -$207; saleable milk (82%) and initial metritis treatment cost (9%) accounted for most of the variation. The mean difference in gross profit between the UNT and the CEF group was -$250; replacement cost (41%) and cow sales (31%) accounted for most of the variation. In summary, metritis caused large economic losses when left untreated, and CEF reduced those losses by improving fertility, reducing culling and replacement cost, and reducing milk yield losses.

Using chitosan microparticles to treat metritis in lactating dairy cows.

The main objective of this study was to evaluate the efficacy of intrauterine administration of chitosan microparticles (CM) in curing metritis in dairy cows. A secondary objective was to evaluate the effects of metritis treatments on milk yield, survival, and reproductive performance. Cows with a fetid, watery, red-brownish vaginal discharge were diagnosed with metritis. Holstein cows (n = 826) with metritis from 3 dairies located in northern Florida were blocked by parity (primiparous or multiparous) and, within each block, randomly assigned to one of 3 treatments: CM (n = 276) = intrauterine infusion of 24 g of CM dissolved in 40 mL of sterile distilled water at the time of metritis diagnosis (d 0), 2 (d 2), and 4 (d 4) d later; ceftiofur (CEF; n = 275) = subcutaneous injection of 6.6 mg/kg ceftiofur crystalline-free acid in the base of the ear at d 0 and d 3; Control (CON; n = 275) = no treatment applied at metritis diagnosis. All groups could receive escape therapy if condition worsened. Cure was considered when vaginal discharge became mucoid and not fetid. A group of nonmetritic (NMET; n = 2,436) cows was used for comparison. Data were analyzed by generalized linear mixed and Cox's proportional hazard models. Cows in CM and CON had lesser risk of metritis cure on d 12 than cows in CEF (58.6 ± 5.0 vs. 61.9 ± 4.9% vs. 77.9 ± 3.9, respectively). The proportion of cows culled within 60 days in milk (DIM) was greater for cows in CM than for cows in CEF and CON (21.5 ± 2.7 vs. 9.7 ± 1.9 vs. 11.3 ± 2.0%, respectively). Treatment did not affect rectal temperature or plasma nonesterified fatty acids, ß-hydroxybutyrate, and haptoglobin concentrations. Milk yield in the first 60 DIM differed for all treatments, and it was lowest for CM (35.8 ± 0.3 kg/d), followed by CON (36.8 ± 0.3 kg/d) and CEF (37.9 ± 0.3 kg/d). The hazard of pregnancy up to 300 DIM was lesser for CM than CEF (hazard ratio = 0.62; 95% CI: 0.50-0.76), for CM than CON (hazard ratio = 0.77; 95% CI: 0.62-0.95) and for CON than CEF (hazard ratio = 0.80; 95% CI: 0.65-0.99). Culling was greater, and milk yield and fertility were lesser for CEF than NMET. In summary, CM did not improve the cure of metritis, and was detrimental to milk yield, survival, and fertility compared with CON. In contrast, CEF increased the cure of metritis, milk yield, and fertility compared with CM and CON. Finally, the negative effects of metritis on milk yield culling and fertility could not be completely reversed by CEF.

Association of dry matter intake and energy balance prepartum and postpartum with health disorders postpartum: Part II. Ketosis and clinical mastitis.

The main objective of this study was to determine the association of dry matter intake as percentage of body weight (DMI%BW) and energy balance (EB) prepartum (-21 d relative to parturition) and postpartum (28 d) with ketosis (n = 189) and clinical mastitis (n = 79). For this, DMI%BW and EB were the independent variables and ketosis and clinical mastitis were the dependent variables. A secondary objective was to evaluate prepartum DMI%BW and EB as predictors of ketosis and clinical mastitis. For this, ketosis and clinical mastitis were the independent variables and DMI%BW and EB were the dependent variables. Data from 476 cows from 9 experiments were compiled. Clinical mastitis was diagnosed if milk from 1 or more quarters was abnormal in color, viscosity, or consistency, with or without accompanying heat, pain, redness, or swelling of the quarter or generalized illness, during the first 28 d postpartum. Ketosis was defined as the presence of acetoacetate in urine that resulted in any color change [5 mg/dL (trace) or higher] in the urine test strip (Ketostix, Bayer, Leverkusen, Germany). Cows that developed ketosis had lesser DMI%BW and lesser EB on d -5, -3, -2, and -1 than cows without ketosis. Each 0.1-percentage point decrease in the average DMI%BW and each 1-Mcal decrease in the average of EB in the last 3 d prepartum increased the odds of having ketosis by 8 and 5%, respectively. Cut-offs for DMI%BW and EB during the last 3 d prepartum to predict ketosis were established and were ≤1.5%/d and ≤1.1 Mcal/d, respectively. Cows that developed ketosis had lesser postpartum DMI%BW and EB and greater energy-corrected milk (ECM) than cows without ketosis. Cows that developed clinical mastitis had lesser DMI%BW but similar prepartum EB compared with cows without clinical mastitis. Each 0.1-percentage point decrease in the average DMI%BW and each 1-Mcal decrease in the average EB in the last 3 d prepartum increased the odds of having clinical mastitis by 10 and 8%, respectively. The average DMI%BW and EB during the last 3 d prepartum produced significant cut-offs to predict clinical mastitis postpartum, which were ≤1.2%/d and ≤1.0 Mcal/d, respectively. Cows that developed clinical mastitis had lesser postpartum DMI%BW from d 3 to 15 and on d 17; greater EB on d 18, from d 21 to 23, and on d 26; and lesser ECM. The main limitation in this study is that the time-order of disease relative to DMI%BW and ECM is inconsistent such that postpartum outcomes were measured before and after disease, which was diagnosed at variable intervals after calving. In summary, measures of prepartum DMI were associated with and were predictors of ketosis and clinical mastitis postpartum, although the effect sizes were small.

Association of dry matter intake and energy balance prepartum and postpartum with health disorders postpartum: Part I. Calving disorders and metritis.

The main objective of this study was to determine the association of dry matter intake as percentage of body weight (DMI%BW) and energy balance (EB) prepartum (-21 d relative to parturition) and postpartum (28 d) with calving disorders (CDZ; dystocia, twins, and stillbirths; n = 101) and metritis (n = 114). For this, DMI%BW and EB were the independent variables and CDZ and metritis were the dependent variables. A secondary objective was to evaluate prepartum DMI%BW and EB as predictors of CDZ and metritis. For this, CDZ and metritis were the independent variables and DMI%BW and EB were the dependent variables. Data from 476 cows from 9 experiments were compiled. Cows that developed CDZ had lesser postpartum DMI%BW from d 3 to 12 and lesser energy-corrected milk (ECM) than cows that did not develop CDZ. Dry matter intake as percentage of BW and EB prepartum did not affect the odds of CDZ. Cows with metritis had lesser prepartum DMI%BW and EB. Each 0.1-percentage point decrease in the average DMI%BW and each 1-Mcal decrease in the average EB in the last 3 d prepartum increased the odds of having metritis by 8%. The average DMI%BW and EB during the last 3 d prepartum produced significant cut-offs to predict metritis postpartum, which were ≤1.6%/d and ≤2.5 Mcal/d, respectively. Cows that developed metritis had lesser overall postpartum DMI%BW and ECM and lesser EB from d 2 to 5 and from d 7 to 11 than cows that did not develop metritis. The main limitation in this study is that the time-order of disease relative to DMI%BW and ECM is inconsistent such that postpartum outcomes were measured before and after disease, which was diagnosed at variable intervals after calving. In summary, prepartum DMI%BW and EB were associated with and were predictors of metritis although the effect sizes were small for metritis, and calving disorders and metritis were associated with decreased DMI%BW and ECM postpartum.

Effects of oral calcium supplementation on productive and reproductive performance in Holstein cows.

The objectives of this experiment were to determine the effects of oral Ca supplementation on milk yield, body condition, pregnancy per artificial insemination (P/AI), and days to pregnancy in Holstein cows considered to be of low (LRM; no calving assistance, live singleton without retained placenta) or high (HRM; at least one of the following: dystocia, twins, stillbirth, retained placenta, or vulvo-vaginal laceration) risk of developing metritis. The hypotheses were that oral Ca supplementation during the early postpartum period would reduce the loss of body condition and improve lactation performance and reproduction. Four hundred fifty Holstein cows were blocked by parity as primiparous cows (n=174) or multiparous cows (n=276). Within parity, a cow considered at HRM was matched with a cow of LRM and the pair was randomly assigned to control (no Ca supplementation), 86g of Ca on d 0 and 1 postpartum (CaS1), or 86g of Ca on d 0 and 1 postpartum followed by 43g/d on d 2 to 4 postpartum (CaS4). Body condition was scored at calving and 32 d postpartum and estrous cyclicity was evaluated at 38 and 52 d postpartum. Milk yield was recorded daily. Multiparous cows were classified as above or below the mean 305-d mature equivalent milk yield based on production in the previous lactation. Reproductive performance was evaluated for the first 210 d postpartum. Body condition did not differ among treatments, and cows lost on average 0.44 units of body condition in the first month of lactation. Calcium supplementation did not affect milk yield in the first 5 mo postpartum. For multiparous cows, Ca supplementation was beneficial to milk yield in the first 30 DIM in cows of greater production potential, but detrimental to multiparous cows with below average production potential. Calcium supplementation to primiparous cows reduced P/AI at first (control=55.8, CaS1=31.5, CaS4=37.0%) and all artificial inseminations (control=48.5, CaS1=34.6, CaS4=38.5%); however, Ca supplementation to multiparous cows improved P/AI at the first (control=32.1, CaS1=38.6, CaS4=41.3%) and all artificial inseminations (control=28.1, CaS1=35.3, CaS4=40.5%). These responses in P/AI to Ca supplementation resulted in extended median days to pregnancy (control=75, CaS1=100, CaS4=94 d) and smaller proportion of pregnant cows (control=89.3, CaS1=83.9, CaS4=83.9%) in primiparous cows, but shorter days to pregnancy (control=115, CaS1=94, CaS4=94 d) and increased proportion of pregnant cows in multiparous cows (control=67.0, CaS1=77.2, CaS4=74.3%). Risk of metritis depressed most measures of reproduction evaluated in the experiment. Results indicate that responses to oral Ca supplementation are conditional on parity and production potential of cows. Oral Ca supplementation was detrimental to reproduction in primiparous cows. On the other hand, Ca supplementation benefited reproduction in multiparous cows and milk yield in the cohort of multiparous cows of greater production potential.

Effects of oral calcium supplementation on mineral and acid-base status, energy metabolites, and health of postpartum dairy cows.

Two experiments were conducted to characterize blood concentrations of minerals and acid-base status after oral dosing of Ca salts and to determine the effects of oral Ca on mineral and metabolic status and incidence diseases. The hypotheses were that administration of oral Ca as CaCl2 and CaSO4 maintains blood total Ca (tCa) concentrations ≥2.125 mM and reduces the incidence of diseases in early lactation. In experiment 1, 18 Holstein cows on the day of calving were assigned to receive a single dose of 0, 43, or 86g of Ca as an oral bolus. Blood was sampled before and after treatments to characterize acid-base status and concentrations of minerals. In experiment 2, 450 Holstein cows considered of low (LRM; normal calving) or high risk (HRM; dystocia, twins, stillbirth, retained placenta, vulvo-vaginal laceration, or a combination of these) of metritis (primiparous-LRM=84; primiparous-HRM=84; multiparous-LRM=138; multiparous-HRM=138) on the day of calving were blocked by parity and then randomly assigned to control, no Ca supplementation; 86g of Ca on d 0 and 1 postpartum (CaS1); or 86g of Ca on d 0 and 1 postpartum followed by 43g/d on d 2 to 4 postpartum (CaS4). Blood was sampled before and 30 min after treatment on d 0, and 30 min after treatments on d 1 to 4, and d 7 and 10 for determination of concentrations of minerals and metabolites and blood acid-base responses. Disease incidence was evaluated for the first 30 DIM. Concentrations of ionized Ca (iCa) increased for 2h in cows supplemented with 43g of Ca and fewer than 8h in cows supplemented with 86g of Ca. The changes in iCa concentrations from pretreatment to 30 min after 86g of Ca supplemented on d 0 were 0.11±0.03 mM in multiparous cows and 0.25±0.03 mM in primiparous cows. Oral Ca reduced the incidence of subclinical hypocalcemia (SCH; tCa <2.125mM) in the first 4 d in the experiment (control=69.3%; CaS1=57.5%; CaS4=34.2%). Calcium supplementation decreased the prevalence of SCH on d 0 and 1 postpartum in all cows. Stopping oral Ca in CaS1 on d 1 postpartum, however, caused a rebound in SCH on d 2 to 4 postpartum in primiparous cows. Oral Ca increased the incidence of metritis (control=22.7%; CaS1=34.8%; CaS4=32.8%), primarily because of an increase in LRM primiparous cows (control=17.9%; CaS1=35.7%; CaS4=42.9%). Oral Ca increased morbidity in primiparous cows (control=38.1%; CaS1=61.8%; CaS4=60.3%) but had no effect on multiparous cows (control=38.2%; CaS1=35.1%; CaS4=30.1%). Large doses of oral Ca as salts of chloride and sulfate in the first days postpartum should be avoided in primiparous cows and used only in cows at risk of clinical hypocalcemia.

Vulvovaginal laceration as a risk factor for uterine disease in postpartum dairy cows.

The main objective was to evaluate the association between vulvovaginal laceration and uterine diseases in dairy cows. The secondary objectives were to evaluate the association between vulvovaginal laceration and cyclicity, and reproductive performance. The vulvovaginal region of 660 Holstein cows from a 5,000 lactating-cows herd was inspected at 4d in milk (DIM) for the presence of lacerations, and scored (VLS) as follows: 0=no laceration; 1=laceration <2cm at the dorsal commissure of the vulva or lateral walls of the vulva/vagina; 2=laceration ≥2cm at the dorsal commissure of the vulva or at the lateral walls of the vulva/vagina, or both. Vaginal discharge was scored at 4, 6, and 8 DIM for diagnosis of metritis, and then at 32 DIM for diagnosis of purulent vaginal discharge (PVD). Data were analyzed using LOGISTIC and PHREG procedures of SAS. Cows with VLS 2 had greater incidence of metritis than cows with VLS 0 (69.1 vs. 42.4%), and cows with VLS 1 tended to have greater incidence of metritis than cows with VLS 0 (52.0 vs. 42.4%). Cows with VLS 2 had greater incidence of PVD than cows with VLS 0 (56.5 vs. 43.1%). A lower proportion of cows with VLS 2 than VLS 0 were cyclic by 64 DIM (70.0 vs. 86.8%). A lower proportion of cows with VLS 2 than VLS 0 were pregnant at 60 d after first AI (28.7 vs. 33.6%). Proportion of pregnant cows at 60d after AI tended to be lower for VLS 1 than VLS 0 (28.4 vs. 33.6%). Hazard of pregnancy by 300 DIM was not affected by VLS. Hazard of pregnancy was decreased for cows with metritis, PVD, and anovular cows. In summary, vulvovaginal laceration was associated with uterine disease and cyclicity, which were negatively associated with reproductive performance. Vulvovaginal laceration was recognized as a risk factor for postpartum uterine disease.

Clinical response after chitosan microparticle administration and preliminary assessment of efficacy in preventing metritis in lactating dairy cows.

The objectives were to evaluate the clinical response to intrauterine administration of chitosan microparticles (CM) and to assess efficacy for preventing metritis in dairy cows. Holstein cows (n=104; 40 primiparous and 64 multiparous) at increased risk for metritis (cows that had abortion, dystocia, twins, stillbirth, or retained placenta) were randomly assigned to 1 of 2 treatments at 1d in milk (DIM; 24h postpartum): CM group (n=52), daily intrauterine infusion of 8g of CM dissolved in 40mL of sterile water for 5d; control (CON) group (n=52), daily intrauterine infusion of 40mL of sterile water for 5d. Clinical response was assessed by evaluation of parameters associated with inflammation (rectal temperature and plasma haptoglobin concentration) and metabolism [plasma nonesterified fatty acid (NEFA) and ß-hydroxybutyrate (BHB) concentrations] up to 14 DIM, and daily milk yield up to 30 DIM. Uterine discharge pH was evaluated at 4, 7, 10, and 14 DIM as an indicator of bacterial load and acid byproduct production. The cumulative incidence of metritis was evaluated up to 4, 7, 10, and 14 DIM. Continuous and dichotomous outcomes were evaluated with mixed linear and logistic regression analysis, respectively. Treatment with CM did not affect rectal temperature (39.17±0.04 vs. 39.14±0.04°C), haptoglobin (1.10±0.05 vs. 1.07±0.05mg/mL), NEFA (0.64±0.04 vs. 0.63±0.04mmol/L), BHB (0.61±0.03 vs. 0.57±0.03mmol/L), or milk yield (30.3±0.92 vs. 30.1±0.97kg/d) compared with CON. An interaction between treatment and time showed that NEFA concentrations were lower for CM than CON at 10 DIM (0.46±0.06 vs. 0.64±0.06mmol/L). Treatment with CM resulted in greater uterine discharge pH than CON (6.91±0.03 vs. 6.83±0.02). Cows that developed metritis had increased concentrations of haptoglobin and BHB, and decreased uterine discharge pH and milk yield. Treatment with CM resulted in decreased incidence of metritis up to 7 DIM compared with CON (46.2 vs. 65.4%); however, no differences were found at 4 (11.5 vs. 17.3%), 10 (61.5 vs. 73.1%), and 14 DIM (63.5 vs. 73.1%) for CM versus CON, respectively. In conclusion, CM did not alter clinical parameters of cows at risk for metritis, and may merit further investigation for prevention of metritis. However, the duration of treatment may have to be extended to effectively reduce the incidence of metritis during the high-risk period.

Effect of intrauterine infusion of an organic-certified product on uterine health, survival, and fertility of dairy cows with toxic puerperal metritis.

The objective was to evaluate the effect of intrauterine infusion of an organic certified product (Optimum UterFlush, Van Beek Natural Science, Orange City, IA) on uterine health, survival, and fertility of cows affected with toxic puerperal metritis (TPM) in an organic dairy farm. Cows with TPM were defined as having an abnormally enlarged uterus and a fetid watery red-brown vaginal discharge, associated with systemic illness and fever (rectal temperature ≥39.5°C), within 12 d postpartum. Cows diagnosed with TPM (n=220; study d 0) were blocked by parity (1 and ≥2) and randomly assigned into 1 of 2 intrauterine treatments applied every other day for a total of 3 applications: (1) control (CON)=200mL of povidone iodine diluted in 2L of distilled water (n=113); (2) Optimum UterFlush (UF)=3.75mL diluted in 117mL of distilled water (n=107). All enrolled cows received hypertonic saline solution (500mL 7.2% i.v.), dextrose (500mL 50% i.v.), and oral aspirin (5 boluses/d). Outcome variables for treatment efficacy included fever and presence of fetid vaginal discharge at study d 6 and 14, survival at study d 6 and 14 and at 30 and 100 DIM, and reproductive performance. Control variables were parity, BCS at enrollment, calving season, and milk yield. Occurrence of fever at d 6 and 14 was not different between the 2 treatment groups. Presence of fetid vaginal discharge at d 6 and 14 was lower in cows treated with UF compared with cows in the CON group (10.7 vs. 28% and 1.1 vs. 9.1%). The odds (95% confidence interval) for survival and remaining in the farm at study d 6 and 14 and at 30 and 100 DIM for cows in the UF treatment were 4.67 (1.38-15.8), 2.77 (1.25-6.10), 3.13 (1.22-8.02), and 2.82 (1.38-5.71) times the odds of cows in the CON group, respectively. The odds of AI until 150 DIM and the interval from calving to first AI were not different between the 2 treatments. However, pregnancy was affected by treatment; the odds (95% confidence interval) of pregnancy at the first AI, 150 DIM, and 300 DIM for cows treated with UF were 2.15 (1.05-4.40), 1.81 (1.04-3.15), and 1.92 (1.09-3.38) times the odds of cows in the CON group, respectively. Days to pregnancy were similar in both treatment groups, but the number of artificial inseminations per pregnancy were different (2.69 vs. 2.02 for cows in the CON and UF treatments). Results indicate that cows with TPM administered intrauterine infusion of Optimum UterFlush had higher odds of recovering and improved reproductive performance compared with cows treated with povidone iodine.

Factors associated with early cyclicity in postpartum dairy cows.

The objective of this study was to evaluate factors associated with resumption of ovarian cyclicity within 21 days in milk (DIM) in dairy cows. Cows (n=768) from 2 herds in north Florida had their ovaries scanned at 17±3, 21±3, and 24±3 DIM. Cows that had a corpus luteum ≥20mm at 17±3 or at 21±3 DIM or that had a corpus luteum <20mm in 2 consecutive examinations were determined to be cyclic by 21±3 DIM. The following information was collected for up to 14 DIM: calving season, parity, calving problems, metabolic problems, metritis, mastitis, digestive problems, lameness, body weight loss, dry period length, and average daily milk yield. Body condition was scored at 17±3 DIM. Multivariable mixed logistic regression analysis was performed using the GLIMMIX procedure of SAS. Variables with P≤0.2 were considered in each model. Herd was included as a random variable. Three models were constructed: model 1 included all cows, model 2 included only cows from dairy 1 that had daily body weights available, and model 3 included only multiparous cows with a previous dry period length recorded. In model 1, variables associated with greater cyclicity by 21±3 DIM were calving in the summer and fall rather than in the winter or spring, being multiparous rather than primiparous, and not having metabolic or digestive problems. In model 2, variables associated with greater cyclicity by 21±3 DIM were calving in the summer and fall, not having metritis or digestive problems and not losing >28 kg of BW within 14 DIM. In model 3, variables associated with greater cyclicity by 21±3 DIM were absence of metabolic problems and dry period ≤76 d. In summary, cyclicity by 21±3 DIM was negatively associated with calving in winter or spring, primiparity, metritis, metabolic or digestive problems, loss of >28 kg of body weight, and a dry period >76d. Strategies preventing extended dry period length and loss of BW, together with reductions in the incidence of metritis as well as metabolic and digestive problems should improve early cyclicity postpartum.

Effect of delayed breeding during the summer on profitability of dairy cows.

The objective of this retrospective observational cohort study, combined with simulation, was to evaluate the effect of extending the voluntary waiting period (VWP) during the summer on profitability on a Florida dairy farm. Data from Holstein cows (n=1,416) that calved between June and September of 2007 and 2008 were used. Cows that calved between June 1 and July 21 (regular group; REG; n=719) were artificially inseminated (AI) for the first time upon estrus detection (ED) after the second PGF2α of the Presynch protocol administered between 57 and 63 d in milk (DIM), or underwent timed AI using the Ovsynch protocol (TAI) if not detected in estrus. Cows that calved between July 22 and September 18 (extended group; EXT; n=697) underwent AI for the first time after the first or second PGF2α starting November 14 or November 21 or underwent TAI if not detected in estrus. For second and subsequent AI, all cows underwent AI upon ED or enrolled on TAI after nonpregnancy diagnosis. Following these schemes, average VWP in the REG group and EXT group were 60 and 83 d, respectively. Overall profitability for both experimental and subsequent parities were calculated by subtracting the costs existing of feeding costs ($0.30/kg lactating cow diet; $0.25/kg dry cow diet), breeding costs ($2.65/dose PGF2α; $2.40/dose GnRH; $0.25/injection administration; $10/semen straw; $5/AI; $3/pregnancy diagnosis), and other costs ($3/d) from the daily revenues with milk sales ($0.44/kg of milk), cow sales ($1.76/kg of live weight), and calf sales ($140/calf). A herd budget simulation was used to predict future cash flow after culling or end of subsequent parity until 6 yr after the start of the study to account for all cash flow consequences of extended VWP. Cows in the EXT group had greater first-service pregnancy per AI (PAI1) but still had greater days open and calving interval. Delaying breeding did not affect total cash flow because the EXT group had greater combined profitability for the experimental parity and subsequent parity but lesser future cash flow. Delayed breeding during the summer increased PAI1 but did not improve overall reproductive efficiency and did not affect overall profitability.

Efficacy of ampicillin trihydrate or ceftiofur hydrochloride for treatment of metritis and subsequent fertility in dairy cows.

Our objectives were to evaluate the efficacy of ampicillin trihydrate for the treatment of metritis in dairy cows compared with ceftiofur hydrochloride and the subsequent effects on pregnancy at first insemination (P/AI). Cows in the first 12 d in milk (DIM) with a uterine discharge score of 5 (watery, reddish or brownish discharge of foul smell) and rectal temperature <39.5°C were diagnosed with metritis based on the fetid discharge, and cows with metritis and rectal temperature ≥39.5°C were diagnosed as having puerperal metritis. Cows with metritis (n=528) were blocked by parity and type of metritis as fetid discharge or puerperal metritis and, within each block, assigned randomly to receive 11mg/kg of ampicillin (n=259) or 2.2mg/kg of ceftiofur (n=269) once daily for 5 d. Day of diagnosis of metritis was considered study d 1. A cohort of 268 cows without metritis was selected randomly at 12 DIM. Rectal temperature was measured in cows with metritis on study d 1 to 7, and 12, and vaginal discharge was scored on study d 5, 7, and 12. Metritis cure was characterized by vaginal discharge score of <5 or by vaginal discharge score of <5 and no fever. At 32±3 DIM, vaginal discharge was scored for diagnosis of purulent vaginal discharge. At 39±3 DIM, endometrial cytology was performed. At 53±3 and 67±3 DIM, ovaries were scanned to determine estrous cyclicity. Pregnancy was evaluated after the first AI. Cure of metritis based on vaginal discharge <5 was greater for ampicillin than ceftiofur on d 5 (37.1 vs. 25.2%) and 7 (57.2 vs. 46.3%), but not on d 12 (82.0 vs. 85.0%). Cure of metritis based on vaginal discharge <5 and no fever was greater for ampicillin than for ceftiofur only on d 7 (50.4 vs. 37.9%), but not on d 5 (23.1 vs. 17.6%) and 12 (66.1 vs. 67.4%). Cows with puerperal metritis had reduced cure compared with cows with fetid discharge on d 5 (30.5 vs. 12.8%), 7 (55.2 vs. 33.6%), and 12 (72.0 vs. 61.1%). The proportion of cows with fever on any day after therapy started did not differ between treatments. Fifty-three percent of cows with metritis based on fetid discharge developed fever after initiating antimicrobial therapy. Cows receiving ampicillin had less prevalence of purulent vaginal discharge than those treated with ceftiofur (57.7 vs. 67.8%), but they were both greater than cows without metritis (21.9%). Prevalence of cytological endometritis did not differ between ampicillin and ceftiofur (30.0 vs. 25.4%), but they were both greater than cows without metritis (14.5%). The proportion of estrous cyclic cows (75.0%) and P/AI did not differ among treatments (ampicillin=28.0% vs. ceftiofur=28.3% vs. without metritis=30.5%). Clinical cure was faster for ampicillin than for ceftiofur, but on study d 12 both treatments resulted in similar cure. Clinical cure was less for cows with puerperal metritis than for cows with fetid uterine discharge. Despite differences in uterine health, P/AI at the first insemination did not differ among treatments.

Inducing ovulation early postpartum influences uterine health and fertility in dairy cows.

The objective of the current study was to evaluate the effect of GnRH early postpartum on induction of ovulation, uterine health, and fertility in dairy cows. Holstein cows without a corpus luteum (CL) at 17 ± 3 DIM were assigned randomly to receive i.m. GnRH (n = 245) at 17 ± 3 and 20 ± 3 DIM or remain as controls (n = 245). Ovaries were scanned by ultrasonography twice weekly totaling 4 examinations. Ovulation was characterized by the appearance of a CL ≥ 20 mm at any ultrasound or CL <20mm in 2 consecutive examinations. Clinical and cytological endometritis were diagnosed at 35 DIM. Compared with control, GnRH increased ovulation up to 3.5d after the last treatment (78.7 vs. 45.0%) and did not affect the prevalence of clinical endometritis (23.9 vs. 18.6%) or cytological endometritis (30.9 vs. 32.8%). Prevalence of clinical endometritis increased in cows that had calving problems (32.6 vs. 15.9%) and metritis (40.6 vs. 15.8%). Metritis increased prevalence of cytological endometritis (50.7 vs. 23.5%). Treatment with GnRH did not affect pregnancy per artificial insemination at 32 (37.6 vs. 38.6%) or 74 d after artificial insemination (35.0 vs. 31.5%), but reduced pregnancy loss (6.8 vs. 18.1%). No overall effect of GnRH treatment on hazard of pregnancy was observed; however, an interaction between GnRH treatment and ovulation showed that GnRH-treated cows that ovulated had increased hazard of pregnancy by 300 DIM compared with GnRH-treated and control cows that did not ovulate (hazard ratio=2.0 and 1.3, respectively), but similar to control cows that ovulated (hazard ratio=1.1). Gonadotropin-releasing hormone early postpartum induced ovulation without affecting uterine health, but failed to improve pregnancy per artificial insemination or time to pregnancy, although it reduced pregnancy loss.

Effect of induced subclinical hypocalcemia on physiological responses and neutrophil function in dairy cows.

The objectives were to study the effects of induced subclinical hypocalcemia [SCH, blood ionized Ca (iCa(2+)) <1.0mM, without recumbency] on physiological responses and function of immune cells in dairy cows. Ten nonpregnant, nonlactating Holstein cows were blocked by lactation and assigned randomly to a normocalcemic (NC; intravenous infusion of 0.9% NaCl i.v. plus 43 g of oral Ca, as Ca sulfate and Ca chloride, at -1 and 11h) or an induced SCH [SCHI, 5% ethylene glycol tetraacetic acid (EGTA), a selective iCa(2+) chelator, intravenous infusion] treatment for 24h, using a crossover design. The sequence of treatments was either NC-SCHI or SCHI-NC, with a 6-d washout period. Ionized Ca was evaluated before, hourly during the infusion period, and at 48 and 72 h, to monitor concentrations and adjust the rate of infusion, maintaining blood iCa(2+) <1.0mM in SCHI throughout the 24-h infusion period. Additional measurements included heart and respiratory rates, rectal temperature, dry matter intake, rumen contractions, whole-blood pH, concentrations of glucose and K in whole blood, concentrations of total Ca, Mg, nonesterified fatty acids, ß-hydroxybutyrate, and insulin in plasma, and urinary excretion of Ca. Total and differential leukocyte count in blood was also performed. The concentration of cytosolic iCa(2+) in neutrophils and lymphocytes was quantified and neutrophil function was assayed in vitro. Infusion of a 5% EGTA solution successfully induced SCH in all SCHI cows, resulting in decreased blood iCa(2+) concentrations throughout the 24-h treatment period (0.77 ± 0.01 vs. 1.26 ± 0.01 mM iCa(2+)). Induction of SCH reduced dry matter intake on the day of infusion (5.3 ± 0.8 vs. 9.1 ± 0.8 kg/d) and rumen contractions (1.9 ± 0.2 vs. 2.7 ± 0.2 contractions/2 min) for the last 12h of infusion. Cows in SCHI had decreased plasma insulin concentration (1.44 ± 0.23 vs. 2.32 ± 0.23 ng/mL) evident between 6 and 18 h after the beginning of the infusion, accompanied by increased concentrations of glucose (4.40 ± 0.04 vs. 4.17 ± 0.04 mM). Plasma nonesterified fatty acids concentration was greater for SCHI than NC cows (0.110 ± 0.019 vs. 0.061 ± 0.014 mM). Neutrophils of cows in SCHI had a faster decrease in cytosolic iCa(2+) after stimulation with ionomycin (9.9 ± 1.0 vs. 13.6 ± 1.4 Fluo-4:Fura Red post-end ratio) in vitro. Furthermore, induction of SCH reduced the percentage of neutrophils undergoing phagocytosis (22.1 ± 2.1 vs. 29.3 ± 2.1%) and reduced the oxidative burst response after incubation of pathogenic bacteria (16.1 ± 1.7 vs. 24.2 ± 1.7%). Subclinical hypocalcemia compromised appetite, altered metabolism, and impaired function of immune cells in dairy cows.

Effect of feeding maternal colostrum or plasma-derived or colostrum-derived colostrum replacer on passive transfer of immunity, health, and performance of preweaning heifer calves.

The objective of this study was to evaluate the effect of feeding maternal colostrum (MC), a plasma-derived (PDCR) or colostrum-derived colostrum replacer (CDCR) on passive transfer of immunity, health, and performance of preweaning heifer calves. Preplanned contrasts were performed for MC versus CR (PDCR combined with CDCR) and PDCR versus CDCR. At birth, calves were randomly assigned to 1 of 3 treatment groups: MC (n=49), 3.8L of maternal colostrum; PDCR (n=49), 550 g (1 dose; 150 g of IgG) of a PDCR; or CDCR (n=49), 470 g (1 dose; 100g IgG) of a CDCR. The best total protein cutoff for determining passive transfer was >5.2, 5.6, and 5.1g/dL for MC, PDCR, and CDCR, respectively. Serum total protein was greater for calves fed MC (mean ± SE; 6.14 ± 0.11 g/dL) than for calves fed PDCR (5.29 ± 0.11 g/dL) and CDCR (5.27 ± 0.11 g/dL). Serum IgG concentrations were greater for calves fed MC (2,098 ± 108 g/dL) than for calves fed PDCR (927 ± 107 g/dL) or CDCR (1,139 ± 108 g/dL). Apparent efficiency of absorption was greater for CDCR than PDCR (38.8 ± 3.0 vs. 21.6 ± 3.0%). Adequate passive transfer was greatest for MC (91.8%), followed by CDCR (49%) and PDCR (28.6%). Calves fed MC had greater weaning weights and body weight gain than calves fed CR. Morbidity was lower for calves fed MC (46.9%) than for calves fed PDCR (71.4%) or CDCR (67.3%). Calves fed MC tended to have lower mortality than calves fed CR. Given the conditions of this trial, feeding 3.8L of MC was superior to feeding one dose of CR. Further research is needed to evaluate calf performance when a higher dose of CR is fed.

Clinical endometritis in an Argentinean herd of dairy cows: risk factors and reproductive efficiency.

The objectives of this study were to assess the clinical and metabolic risk factors for clinical endometritis, the likelihood for having a normal vaginal discharge during postpartum, and the effects of endometritis on milk yield, reproductive efficiency, and metabolic status in Holstein cows. The study was conducted in a commercial dairy herd (Cordoba, Argentina) where 303 Holstein cows were enrolled. Cows were body condition scored (1 to 5) and tail bled on -14, 7, 21, 31, 41, and 50 d relative to parturition. Cows having a vaginal discharge with presence of pus between 21 and 41 d postpartum (dpp) were diagnosed as having clinical endometritis. Plasma blood samples were analyzed for nonesterified fatty acids (NEFA), ß-hydroxybutyrate (BHBA), and blood urea nitrogen using commercial kits and insulin-like growth factor 1, insulin, and leptin by RIA. Data were analyzed with PROC MIXED, PROC GENMOD, and PROC PHREG of SAS (SAS Institute Inc., Cary, NC). Abnormal calving and puerperal metritis increased the risk for endometritis [adjusted odds ratio (AOR)=2.21 for both]. High prepartum NEFA and high postpartum BHBA increased the risk for endometritis (AOR=1.003 and 1.001, respectively), whereas high prepartum blood urea nitrogen reduced it (AOR=0.853). Cut-offs of 456.6 µM NEFA and 402.5 µM BHBA had sensitivities of 0.69 and 0.58, and specificities of 0.88 and 0.86, respectively. The likelihood for having normal vaginal discharge increased with time (∼1% × dpp) and with normal calving. Cows with endometritis had higher milk yield than normal herdmates (27.8±0.9 vs. 25.7±0.4 kg/d), lower risk for pregnancy by 100 dpp (AOR=0.10), higher nonpregnancy risk by 200 dpp (AOR=2.87), and higher risk for culling than normal cows (AOR=2.28). Cows with endometritis had a lower hazard rate (0.44) for pregnancy and had approximately 70 d longer calving-to-conception intervals. Finally, endometritis had no effect on metabolic hormones. In conclusion, the risk for clinical endometritis increases with abnormal calving and puerperal metritis, as prepartum NEFA and postpartum BHBA concentrations increase. Prepartum NEFA and postpartum BHBA could be useful for the prediction of endometritis. Last, clinical endometritis has detrimental effects on reproductive efficiency, as affected cows take longer to get pregnant and are at higher risk for culling.

Metritis in dairy cows: risk factors and reproductive performance.

The objectives of this study were to assess the risk factors for metritis, its effects on milk yield and on reproductive performance, and the efficacy of ceftiofur therapy in Holstein dairy cows. Cows (n=303) from a commercial dairy herd in Argentina were studied. Cows were scored for body condition, and blood samples were collected on d -14, 7, 21, 31, 41, and 50 relative to parturition. Cows having a watery, purulent, or brown, and fetid vaginal discharge (VD) and rectal temperature ≤ 39.2°C were diagnosed as having clinical metritis, and those having a similar VD and rectal temperature >39.2°C were diagnosed as having puerperal metritis. Both clinical and puerperal metritis cows were randomly assigned to control (no treatment) or ceftiofur group (2.2mg/kg×3 consecutive days). Cure was declared if clear VD was observed at 21 d in milk (DIM). Blood samples were analyzed for nonesterified fatty acids, ß-hydroxybutyrate, and blood urea nitrogen using commercial kits, and for insulin-like growth factor-1, insulin, and leptin by RIA. Data were analyzed with PROC MIXED, GENMOD, PHREG, and LIFETEST from SAS (SAS Institute Inc., Cary, NC). The risk for metritis increased with dystocia, retained fetal membranes, and dead calf [AOR (adjusted odds ratio)=2.58, 95% CI: 1.189-5.559], and as prepartum nonesterified fatty acids levels increased (AOR=1.001, 95% CI: 0.999-1.002). Conversely, risk decreased as prepartum insulin-like growth factor-1 increased (AOR=0.65, 95% CI: 0.349-1.219). Cows having either clinical or puerperal metritis produced less milk by 90 DIM than did healthy cows (2,236 ± 172 vs. 2,367 ± 77 vs. 2,647 ± 82 kg, respectively). Cows with puerperal metritis had lower risk for pregnancy by 100 DIM (AOR=0.189, 95% CI: 0.070-0.479) and a lower hazard rate for pregnancy by 150 DIM (hazard rate: 0.753, 95% CI: 0.621-0.911), and took longer to get pregnant (129 vs. 111 vs. 109 d, for puerperal metritis, clinical metritis, and healthy cows, respectively). Ceftiofur treatment was not associated with cure rate or milk yield but was related to increased risk for pregnancy at timed artificial insemination (AOR=2.688, 95% CI: 0.687-10.832), and for lower risk of reproductive cull (AOR=0.121, 95% CI: 0.014-1.066). In conclusion, abnormal calving and negative energy balance are associated with increased risk for metritis. Metritis, especially puerperal metritis, correlates with reduced milk production and poor reproductive performance. Finally, the likelihood for having a normal VD (indicative of cure) increased 2.6% for every day of increase in postpartum time and was 2 times higher for cows with clinical metritis than for those with puerperal metritis.

Events occurring during the previous lactation, the dry period, and peripartum as risk factors for early lactation mastitis in cows receiving 2 different intramammary dry cow therapies.

The objective of this study was to investigate the association between mastitis events occurring during the previous lactation, the dry period, and the peripartum period on the incidence of early lactation mastitis in cows receiving ceftiofur hydrochloride or penicillin dihydrostreptomycin as intramammary dry cow antibiotic therapy. Cows (n=402) from 2 large dairy farms in Central Florida were enrolled in the study at the time of dry-off processing and were randomly assigned to 1 of 2 dry cow therapies: ceftiofur hydrochloride or penicillin dihydrostreptomycin. Composite milk samples were collected at dry-off and after calving for bacteriological examination and somatic cell count. Peripartal health disorders were monitored during the first 30 d of lactation and included calving difficulty, metritis, ketosis, and left displaced abomasum. Milk production and individual somatic cell scores (SCS) were recorded monthly by the Dairy Herd Improvement Association. The main outcome variables were the risk of clinical mastitis during the first 30 and 60 d of lactation, and the risk of subclinical mastitis at the first 2 monthly Dairy Herd Improvement Association tests after calving (up to 70 d in milk). Additionally, the SCS and the presence of mastitis pathogens in milk at dry-off and at calving were analyzed. Explanatory variables consisted of events occurring during the previous lactation, at dry-off and during the dry period, at calving, and within the first 30 d after calving. Multiple events occurring during the previous lactation had a significant effect on the incidence of mastitis in the subsequent lactation. These events included low milk yield, intermediate lactation length, clinical mastitis, and lactation SCS average. Similarly, intramammary infections with environmental bacteria at dry-off increased the chances of clinical mastitis the first month after calving. Dry-off therapy had a significant effect on mastitis incidence; cows treated with ceftiofur hydrochloride had lower odds of having clinical and subclinical mastitis in the subsequent early lactation compared with cows treated with penicillin dihydrostreptomycin.