Katherine C. Creutzinger

In the United States, nonreplacement calves born on dairies are often sold in the first days of life and experience multiple transport events that increase their risk of disease as they enter the dairy-beef sector. The objectives of this cross-sectional cohort study were to evaluate the condition of dairy-beef calves on arrival at calf-raising farms in the Midwestern United States and to identify factors associated with poor health outcomes. From February 2024 to January 2025, 1,436 calves (∼3-7 d of age) were enrolled 6.4 ± 7.2 h after arrival at 20 dairy-beef calf-raising farms (n = 72 calves/farm) in Indiana, Ohio, Wisconsin, and Iowa. Standardized scoring systems were used to perform a clinical health assessment, and a blood sample was collected from each calf to measure serum total protein (STP) as an indicator of failed transfer of passive immunity (FTPI). On a subset of farms (n = 11) where immediate blood sampling was possible after arrival, blood biochemistry was further analyzed for a target of 30 calves/farm (n = 327). Variables were dichotomized using clinically relevant cut points. Given clustering within farms, 95% CI for prevalence estimates of poor health and blood biochemistry outcomes were calculated, with farm specified as the cluster variable. On arrival, 48.3% (95% CI: 45.7%-51.0%) of calves had diarrhea, 35.8% (33.3%-38.3%) had dehydration, 22.0% (19.9%-24.2%) had navel inflammation, and 18.7% (16.7%-20.8%) had depression. Seventy-seven percent (70.6%-83.4%) of calves had at least one poor health outcome, and 40.0% (33.9%-46.2%) had 2 or more. Blood biochemical analyses indicated 21.6% (19.4%-23.7%; cut-point STP <5.1 g/dL) of calves had FTPI, 48.3% (29.0%-67.6%; glucose 0.72 mmol/L) had elevated serum NEFA. Calves sourced from calf dealers were more likely to have FTPI than those arriving directly from dairy farms. Calves with successful transfer of passive immunity had lower odds of experiencing diarrhea or hypoglycemia on arrival, and calves with a normal fecal score had lower odds of experiencing concurrent dehydration, depression, or hypoglycemia. These results suggest a high percentage of dairy-beef calves in the Midwestern United States arrive at calf-raising farms with FTPI, low energy reserves, and clinical disease that may impact long-term welfare and productivity.

The non-lactation ("dry") period and first few weeks after calving are a crucial time in a dairy cow's life which can greatly impact her welfare and success within a herd. Additionally, cow-calf separation has become a controversial topic in dairy production and there is a knowledge gap regarding the time of calf removal from the cow on US dairy farms. A description of animal management practices during the dry period and early lactation can provide key information if recommended practices are being implemented and what can be changed to enhance the overall welfare of transition cows. The objective of this study was to characterize farmer-reported housing, management, and disease incidence of dairy cows from 60 d before to 30 d after calving on dairy farms in Wisconsin and Minnesota. Surveys were mailed to a random sample of 1,503 dairy producers in Wisconsin (n = 948) and Minnesota (n = 555). The survey included questions regarding farm demographics, cow management from 60 d before 30 d after calving, calf separation practices, and transition cow disease incidence. The response rate was 31% (466/1,503; Minnesota: n = 145, Wisconsin: n = 321) at the end of the 10 wk data collection period. Respondents had an average of 219.5 ± 712.3 (±SD) milking cows with a range of 2-12,000 milking cows. Cow management varied greatly between farms during the dry period and early lactation. The most common dry cow housing used was a close-up pen (38% of farms) and freestalls for both fresh (15.9%) and lactating cows (39.3%). Cows were moved into new pens 0 - 6 times (median = 2) during the 60 d before to 30 d after calving and approximately one quarter of farms (26%) moved cows into new pens twice. Removal of calves from the calving pen was most commonly reported to occur less than 1 h (16.7% of farms), 1.1 to 2 h (22.3%), and 2.1 to 12 h (39.5%) after birth. Calf removal from the calving pen was reported to occur sooner after birth on farms with larger herds and if cows remained in the calving pen for less time after calving. Dystocia was reported to occur at a greater incidence than other transition diseases (7.0% ± 7.4), followed by retained placenta (6.4% ± 6.5). The results of this survey provide evidence that recommended care practices, such as using a calving pen and not overstocking a fresh cow pen, are being provided to dry and early-lactation cows on many dairy farms in this region. However, animal-based measures would be required to assess if cows are in a good welfare state. Nonetheless, these results can help identify possible barriers to success and opportunities for improvement for the management and potential performance of dairy cows.

The objective of this study was to investigate the effects of feeding surplus dairy calves a milk replacer (MR) or one of 2 different oral rehydration solutions (ORS) during a midtransportation rest period on metabolic and clinical health indicators, growth, and behavioral outcomes after arrival at a calf-raising facility. Surplus dairy calves (n = 128) were transported in 4 cohorts from February to July 2022 for 12 h to a holding facility, rested for 8 h, then transported for an additional 6 h to a calf-raising facility. Upon arrival at the holding facility, calves were randomly assigned to 1 of 3 treatments: MR (n = 43), a high-sodium ORS developed for diarrhea (ORS-D; n = 43), or a high-potassium ORS developed for transportation (ORS-T; n = 42). The exact age of calves at transportation was unknown; however, all calves were less than 14 d of age. Calf BW at enrollment was 43.9 +/- 5.9 kg, 43.7 +/- 6.5 kg, and 45.0 +/- 4.5 kg for calves fed MR, ORS-D, and ORS-T, respectively. Calves were fed 2.0 L of their treatment twice, once upon arrival and once before leaving the holding facility. At unloading and reloading at the holding facility, calves were weighed and blood samples were obtained. Calves were also health scored at unloading at the holding facility. After arrival at the calf-raising facility, calves were weighed, health scored, and blood samples were taken. Blood samples were collected at 24 and 48 h and BW was recorded at 24 h, 48 h, 72 h, 5 d, 7 d, 14 d, and at 8 wk after arrival at the calf-raising facility. Calves were also health scored daily for 14 d; health scoring included fecal consistency scoring and evaluating the presence or absence of respiratory disease. Lying time, lying bouts, and activity index were measured during transportation and from 3 d relative to transportation using accelerometers. At arrival to the calf-raiser, calves fed ORS-D had higher concentrations of nonesterified fatty acids (NEFA) and BHB than calves fed MR. Furthermore, calves fed ORST had higher concentrations of BHB at arrival to the calf raiser compared with calves fed MR. In the 14 d after arrival at the calf-raiser, there was evidence that calves fed ORS-T had a higher proportion of days with diarrhea and respiratory disease compared with those fed MR. During transportation, calves fed ORS-T had a lower activity index than calves fed MR, suggesting that ORS-T calves had lower overall activity. In addition, on the day of transportation (d 0), ORS-T and ORS-D calves had a lower activity index than calves fed MR. There were no treatment effects on growth outcomes. The results of this study suggest that feeding MR rather than an ORS during a midtransportation rest period could minimize fat mobilization and can potentially improve diarrhea and respiratory disease but does not affect growth outcomes after arrival at calf-raisers.

The objective of this diagnostic accuracy study was to develop and validate an alert to identify calves at risk for a diarrhea bout using milk feeding behavior data (behavior) from automated milk feeders (AMF). We enrolled Holstein calves (n = 259) as a convenience sample size from 2 facilities that were health scored daily preweaning and offered either 10 or 15 L/d of milk replacer. For alert development, 132 calves were enrolled and the ability of milk intake, drinking speed, and rewarded visits collected from AMF to identify calves at risk for diarrhea was tested. Alerts that had high diagnostic accuracy in the alert development phase were validated using a holdout validation strategy of 127 different calves from the same facilities (all offered 15 L/d) for -3 to 1 d relative to diarrhea diagnosis. We enrolled calves that were either healthy or had a first diarrheal bout (loose feces ≥2 d or watery feces ≥1 d). Relative change and rolling dividends for each milk feeding behavior were calculated for each calf from the previous 2 d. Logistic regression models and receiver operator curves (ROC) were used to assess the diagnostic ability for relative change and rolling dividends behavior relative to alert d) to classify calves at risk for a diarrhea bout from -2 to 0 d relative to diagnosis. To maximize sensitivity (Se), alert thresholds were based on ROC optimal classification cutoff. Diagnostic accuracy was met when the alert had a moderate area under the ROC curve (≥0.70), high accuracy (Acc; ≥0.80), high Se (≥0.80), and very high precision (Pre; ≥0.85). For alert development, deviations in rolling dividend milk intake with drinking speed had the best performance (10 L/d: ROC area under the curve [AUC] = 0.79, threshold ≤0.70; 15 L/d: ROC AUC = 0.82, threshold ≤0.60). Our diagnostic criteria were only met in calves offered 15 L/d (10 L/d: Se 75%, Acc 72%, Pre 92%, specificity [Sp] 55% vs. 15 L/d: Se 91%, Acc 91%, Pre 89%, Sp 73%). For holdout validation, rolling dividend milk intake with drinking speed met diagnostic criteria for one facility (threshold ≤0.60, Se 86%, Acc 82%, Pre 94%, Sp 50%). However, no milk feeding behavior alerts met diagnostic criteria for the second facility due to poor Se (relative change milk intake -0.36 threshold, Se 71%, Acc 70%, and Pre 97%). We suggest that changes in milk feeding behavior may indicate diarrhea bouts in dairy calves. Future research should validate this alert in commercial settings; furthermore, software updates, support, and new analytics might be required for on-farm application to implement these types of alerts.

Many indoor-housed cows isolate at calving when given the opportunity, and calving behaviors vary by blind and pen design. The objectives of this study were to determine if cows preferred calving in a visibly separated (blind) or an open area of a group maternity pen, and if there was a preference for the degree of seclusion provided by the blind (50% vs. 100% coverage). Two calving blinds were provided in a group calving pen, and the amount of visibility through the blinds was created using firehoses secured from the top of a metal frame that lined the entire front of the blind (100%) or with every other hose rolled up (50%). Holstein cows and heifers (n = 79) were enrolled into a dynamic group calving pen 21 ± 3 d before calving. Calving location, the difference in blind use prior to calving compared to a baseline period, and social behaviors were recorded using video observation. There was no difference in the number of cows that calved in or outside of a blind (28 vs. 37 calvings, respectively). Cows were more likely to calve in a blind during the day than at night and as the number of cows in the pen increased. For cows who calved in a blind, there was no preference for calving in the 50% or 100% blind (10 vs. 18, respectively). Providing a varied environment for intensively managed cattle can improve their welfare by allowing cows the opportunity to perform natural behaviors and choice over their environment.

Surplus dairy calves are commonly transported long distances from dairy farms to calf-raising facilities and livestock auctions. Current calf transportation research mainly describes physiological changes resulting from transportation. However, few studies have described the impact of transportation on calf behavior. The main objective of this study was to determine the effect of different durations of transportation (6, 12, and 16 h) on lying time and bouts in surplus dairy calves. A secondary objective of this study was to investigate if calf age affected lying behavior around transportation. Surplus dairy calves (n = 175) were transported in 7 cohorts from 5 commercial dairy farms in Ontario to a single veal facility. On the day of transportation (d 0), calves were randomly assigned to one of 3 treatment groups: 1) 6 h (n = 60), 2) 12 h (n = 58), and 3) 16 h (n = 57) of continuous transportation by road. Calf lying and standing behavior was recorded using HOBO data loggers. Daily lying time (h/d) and bouts (no./d) were assessed from -1 to 3 d relative to transportation. The total time spent lying during transportation was assessed as the percentage of time lying (min lying/total min on the trailer × 100) from the time each calf was loaded onto the trailer until the time each calf was unloaded at the veal facility (n = 167). On the day of transportation (d 0), calves transported for 12 and 16 h spent less time lying (6 h: 17.1 h/d; 12 h: 15.9 h/d; 16 h: 15.0 h/d) and had more lying bouts (6 h: 21.9 bouts/d; 12 h: 25.8 bouts/d; 16 h: 29.8 bouts/d) compared with those transported for 6 h. On the day after transportation (d 1), calves transported for 16 h spent more time lying down than calves transported for 6 h (19.9 h/d vs. 18.8 h/d, respectively). In addition, during transportation, calves transported for 12 h and 16 h spent 5.8% and 7.6% more time lying down, respectively, than calves transported for 6 h. On each day relative to transportation (d -1 to 3), younger calves (2 d to 5 d) spent a greater amount of time lying down than older calves (6 d to 19 d) and, overall, had a greater number of lying bouts. The results of this study suggest that longer durations of transportation have an impact on the lying behavior of surplus dairy calves resulting in more fatigue during and after the journey, and therefore, potentially have negative implications on calf welfare. Additionally, longer durations of transportation may be more impactful on younger calves than older calves.