Limited on-animal sensor technology is available to monitor sheep behaviour. We investigated the accuracy and suitability of Hobo Pendant G and IceQube loggers for recording lying behaviour, and steps (IceQube) in pasture-managed sheep. Twenty mixed-breed ewes wore both sensors on their hind legs for 20 consecutive days. Lying behaviour was recorded for 12 h daily (8:00-20:00 h) using video cameras. For step count, four 15-min intervals per sheep (n = 20) were analysed. Bland-Altman plots revealed that the percentage of time recorded as lying per hour by both loggers closely matched video observations. For Hobo/Video and IceQube/Video comparisons, 93% and 99% of data respectively were within +/- 2% of video-observed lying time. The two loggers were also closely matched, with 93% of data within +/- 2%. Sheep spent on average 13.7 +/- 1.24 h (SD) lying per day (range: 7.4-19.2 h). IceQube underestimated steps compared to manual video counts (mean difference; 7 steps, limits of agreement -21.5 to 35.5). After 5 days, one sheep had minor rubbing (IceQube) and after 20 days, 5 sheep had minor or major rubbing from the loggers (3 IceQubes, 4 Hobos). Both loggers accurately captured lying time, but improved attachment materials are needed to prevent rubbing.

Understanding heat stress in dairy cows is important for ensuring their welfare and productivity. While the Temperature Humidity Index is commonly used to determine heat stress conditions it does not consider outdoor factors (e.g. wind speed and solar radiation). To address this, the Grazing Heat Load Index (GHLI) which predicts respiration rate, an indicator of heat stress, was previously developed using data from the Waikato region in New Zealand. This study updated the GHLI using a weather data and animal heat stress indicators (e.g. respiration rate and drooling), collected from dairy herds in the Northland, Waikato, Canterbury, and Southland regions. A mixed-effects linear model, which included air temperature, solar radiation and wind speed as inputs was developed using data from these diverse locations. The updated model slightly outperformed the previous model on a validation dataset when predicting respiration rate. While air temperature remained the primary driver of respiration rate, solar radiation was an exacerbating factor, whereas wind exerted a mitigating effect. Challenges persist in characterising heat stress in conditions such as high wind speed. Non-linear modelling techniques could enhance the predictive capability of the GHLI model, thereby refining heat stress assessment in pasture-based dairy systems nationwide.

This perspective paper provides industry leaders, researchers and policy developers strategic approaches to ensure that the welfare of dairy cattle is protected at the same time as the industry increases its resilience to climate change. Farm systems and practices will evolve in response to the direct impacts of climate change and/or from responses to climate change, such as mitigation strategies to reduce dairy's greenhouse-gas (GHG) emissions. The five domains framework (nutrition, physical environment, health, behaviour, mental state) was used to assess the potential impacts on animal welfare and strategies to minimise these impacts are outlined. Given that the future climate cannot be certain these approaches can be applied under a range of emissions pathways to (1) ensure that the effects of GHG mitigations on animal welfare are considered during their development, (2) engage with end users and the public to ensure solutions to the effects of climate change and weather variability are accepted by consumers and communities, (3) identify and measure the areas where improved animal health can contribute to reducing GHG emissions from dairy production, (4) ensure those supporting farmers to develop and manage their farm systems understand what constitutes a good quality of life for dairy cattle, (5) ensure effective surveillance of animal disease and monitoring of welfare outcomes and farm-system performance in response to climate change and GHG mitigations. Overall, these strategies require a multi-disciplinary co-development approach to ensure that the welfare of dairy cattle is protected at the same time as the industry increases its resilience to the wider impacts of a changing climate.

In countries with pasture-based dairy systems and relatively cold winters, such as New Zealand, it is common to manage pregnant, nonlactating cows on forage crop paddocks rather than pasture, due to slow pasture growth rates. Wintering dairy cattle on grazed crops can compromise welfare if wet and muddy underfoot conditions occur, which can reduce lying. This study investigated behavioral and physiological indicators of welfare of cows under 2 wintering practices: cows managed on and grazed kale crop ( Brassica oleracea), ), and cows managed on pasture with baled hay. Following dry-off (d 0), 80 cows were randomly assigned to 1 of the 2 wintering practices (40 cows/practice) and monitored between d 4 and 32 (phase 1). During this period, lying and stepping behavior was continuously recorded using leg-based accelerometers. Blood samples were obtained at d 0 and 32 for measurements of thyroxine (T4), nonesterified fatty acids (NEFA), white blood cells (WBC), and red blood cells. All data for phase 1 were presented descriptively due to the lack of treatment replication. Daily mean air temperature during this period was 5.2 degrees C (range: 0.0- 10.7 degrees C), and rainfall was 1.1 mm/d (range: 0-5.6mm/d). Between d 4 and 32, cows in both groups spent similar amounts of time lying (pasture with hay cows: 8.9 h/24 h +/- 2.57, kale crop cows: 8.7 h/24 h +/- 3.06, mean +/- SEM). Both groups reduced their lying on wet and cold days, and there was evidence of rebound lying once unfavorable weather conditions stopped. Cows on kale crop had numerically higher NEFA and lower WBC compared with cows managed on pasture, although most physiological values were within normal ranges. In a second phase of the study (d 34 and 35), cows were managed under controlled, replicated conditions in the 2 wintering practices using typical on-farm stocking rates (2 or 4 cows per group in the pasture with hay and kale crop treatments, respectively; n = 10 groups/treatment). During this period, cow behavior, skin and surface temperatures, hygiene scores, feed intakes, and ground conditions were measured. Weather conditions during the 48-h exposure were mostly cold and dry (mean air temperature: 7.8 degrees C, range: -2.2 to 20.5 degrees C). Cows managed on pasture with hay spent more time lying down on the first day of exposure; however, this was likely due to less space being available to kale cows on this day. Cows managed on pasture with hay ruminated more than cows on kale crop on both days of observations (d 1: 37.9% vs. 30.9% of observations, d 2: 36.8% vs. 28.7% of observations for pasture with hay and kale crop groups, respectively) and were lying more often in postures indicative of greater thermal comfort. Cows managed on pasture with hay had higher skin and surface temperatures compared with cows on kale crop, whereas cows on kale crop had dirtier coats. Results suggest that opportunities for thermal comfort were greater for cows managed on pasture with hay bales, which may be due to increased rumination activities and more insulated areas.

Heat stress negatively affects the welfare and production of sheep, particularly in warm climates. Less is known about heat stress and shade requirements of sheep in temperate climates. This study aimed to investigate behavioural and physiological responses of sheep with or without access to shade in summer in New Zealand, which has a predominantly temperate climate. Forty-eight mixed age Romney crossbreed ewes were managed in 4 groups in either shaded (2 m shade/sheep) or unshaded paddocks in a cross-over design (7 days/treatment). A blood sample was obtained before treatments commenced, at the cross-over, and after the second treatment (3 times/sheep) for analyses of red and white blood cells, non-esterified fatty acids (NEFA) and Thyroxine (T). Lying behaviour was recorded continuously using HOBO accelerometers. Shade use, grazing, ruminating, lying, panting and drinking behaviour were recorded for 5 days/treatment using 10-min instantaneous scan sampling between 0900 and 1700 h. Individual respiration rates were obtained 2 times/h during the observation period. Weather was monitored using portable weather stations (mean air temperature was 19.8 degrees C, range: 18.3-23.3 degrees C). Sheep with access to shade were observed using the resource in 25.7% of observations and shade use increased with solar radiation. Unshaded sheep tended to spend more time grazing during the daytime, compared to when shaded (62.6 vs 57.7% of observations, SED=11.92, P=0.080). Both treatment groups were observed ruminating in similar percentage of observations (shaded: 25.5%, unshaded: 22.7% of observations, SED=6.22, P=0.227). Unshaded sheep spent 30.6% of the daytime observations lying down compared to 35.1% for shaded sheep (SED=6.05, P=0.055), however, lying times over 24 h were similar; shaded sheep spent, on average, 12.3 h lying down/24 h compared to 11.8 h for unshaded sheep (SED=0.36, P=0.258). Open mouth panting and tongue out were predominantly observed in unshaded sheep (open mouth: 0.61 vs 0.02%; tongue out: 0.25 vs 0.01% of observations for unshaded and shaded sheep, respectively), however, there were too few observations of these behaviours to be statistically analysed. Unshaded sheep had numerically higher respiration rates than unshaded sheep (130 vs 156 breaths/min, SED=28.5, P=0.410). Average respiration rate was >200 breaths/min on 3 and 7 days for shaded and unshaded animals, respectively. Only sheep without shade had daily average respiration rates >= 300 breaths/min. No physiological effects of warm weather were detected (P >= 0.193). Our results suggest that the welfare of sheep in a temperate climate was improved by providing shade, even in mild summer conditions.

A total of 5500 measurements of the respiration rate of 123 sheep with and without access to shade were obtained on 40 days in the summers (January-April) of 2022(Year 1) and 2023(Year 2). Models to predict respiration rate (breaths per minute (BPM)) based on temperature, humidity, wind speed, and solar radiation were calibrated to the Year 1 unshaded dataset (R2 =0.35, RMSE=39 BPM) and validated with the Year 2 unshaded dataset (R2=0.58, RMSE=40 BPM). Respiration rate increased 6 BPM for each 1 degrees C increase in temperature. The shade treatment decreased respiration rate by 24 BPM and the shaded model for respiration rate had a validation RMSE of 47 BPM. The between sheep variability in respiration rate was described by a standard deviation of 18.9 BPM. The probability of open mouth and tongue out behaviours both increased linearly from 200 BPM. We constructed a daily Heat Load Index based on the cumulative respiration rate greater than 200 BPM. Climate data and sheep density information were used to construct a heat stress risk map for New Zealand from October 2018 to March 2022. Heat stress risk was concentrated in January-February and was primarily located on the east coast of the North Island.

Aims Zoonotic pathogens in bovine herds are major concerns for human and animal health, but their monitoring in animals can be challenging in the absence of clinical signs. Our objective was to determine the association between fecal excretion of Campylobacter jejuni, neonatal immunity, and personality traits of calves. Methods and results Forty-eight dairy calves were reared in three indoor pens from birth to 4 weeks of life. Microbial analyses of the fecal samples collected weekly revealed that the proportion of calves naturally contaminated with C. jejuni in each pen reached 70% after 3 weeks of life. High (>16 g l(-1)) levels of IgG levels in the serum of neonatal calves were negatively (P = .04) associated with fecal detection of C. jejuni over the trial period. Calves that spent more time interacting with a novel object tended to be positive (P = .058) for C. jejuni. Conclusions Overall, the findings indicate that the immunity of neonatal dairy animals and possibly the animal's behavior may contribute to the fecal shedding of C. jejuni.

Management strategies to reduce heat stress are needed, especially when there is no or little shade in pasture -based dairy systems. We investigated management practices used to reduce heat load in summer: milking later when it is cooler, feeding later, and milking only in the morning. Fifteen groups (n = 4 pregnant Friesian -cross cows/group) were managed on pasture and milked at 0700 h followed by a new pasture allocation including silage and one of five afternoon/evening treatments (n = 3 groups/treatment): 1) Late milking (1935 h)/early feed (1630 h), 2) Late milking (1935 h)/late feed (2015 h), 3) Early milking (1550 h)/early feed (1630 h, control), 4) Early milking (1550 h)/late feed (2015 h), 5) Once-a-day milking (OAD): cows were milked only in the morning and provided feed at 1630 h. Lying, grazing and ruminating were recorded using validated accel-erometers over 25 d (mean temperature: 19 degrees C, range: 5-32 degrees C). Body temperature (BT) was recorded using vaginal temperature loggers and respiration rate (RR) was recorded manually. Individual milk production and water intake (group level) were recorded daily. Data were analysed using linear mixed models with group as the experimental unit (n = 3/treatment). There was no evidence of an overall treatment effect at the 5% significance level for grazing, ruminating, lying time, BT or RR, however, the diurnal pattern varied among treatments (grazing, ruminating, lying, BT: P < 0.001). Typically, cows spent more time grazing after fresh pasture was provided followed by rumination, however, this may have resulted in an observed numerical reduction in lying time for cows with delayed milking and/or feeding. Control cows had numerically the highest RR in the after-noon and OAD cows and cows with delayed feeding the lowest. Water intake tended to differ between treatments (P = 0.060); cows milked early in the afternoon consumed most water. Cows with delayed milking had the greatest peak in BT in the afternoon/evening, whereas cows with delayed milking and feeding, and OAD cows had the lowest BT in the afternoon/evening (P < 0.001). Milk production declined over time, which is normal in summer, however, this decline was numerically lowest for cows with delayed milking and feeding. In summary, OAD cows may have experienced reduced heat load. Delaying milking and feeding and milking OAD reduced the afternoon peak in BT that is associated with walking into milking. Modifying milking and feeding times can be used to change diurnal patterns of behaviour but more information is needed to understand what this means for cow welfare.

Dairy cows are motivated to access dry lying surfaces and will seek protection from wind and rain, but winter conditions may limit these opportunities when cows are managed outdoors. The primary aim of this observational study was to determine the effects of weather and paddock soil conditions on lying behavior of dairy cows managed outdoors during winter and fed crop in situ, a practice occurring in New Zealand with year-round grazing of dairy cows. A secondary aim was to characterize eating and ruminating behaviors during winter weather and paddock soil conditions. Four groups (99 nonlactating, pregnant cows each) were managed on 4 outdoor paddock areas on the same farm; the groups were fed pasture silage and grazed either kale (2 groups) or fodder beet (2 groups). Behaviors were recorded using validated leg-based (lying behavior) and ear-based (eating and ruminating time) accelerometers on 30 focal cows in each group over 32 d. Soil depth and wetness were scored daily at 25 points along 4 transects within each paddock area using recognized technical measures (penetrometer, soil volumetric water content), which were compared with practical tools for farmer use (ruler, moisture meter, percentage of sites in paddock scored as dry, wet, sodden, or with surface water pooling). Rainfall occurred most days during the study (mean 1.6 mm/d; maximum 12.2 mm/d), resulting in wet and muddy paddocks (mud depth with ruler: mean 6 cm, maximum 18 cm; paddock sites scored as wet or sodden: mean 34%, maximum 100%; paddock sites with surface water pooling: mean 27%, maximum 100%). Group lying time was 9.6 ± 2.3 h/d (mean ± standard deviation); however, 21% of cows consistently lay less than 8 h/d (to a minimum of 4.9 h/d). A mixed regression model tested the effects of daily weather and paddock soil conditions on daily lying time, with group as the observational unit, day as repeated measure, crop type as a fixed effect, crop type interactions with explanatory variables, and random intercepts of group and paddock within group. Lying time was less on the day of and day after rainfall (24 and 29 min/d less for 1 mm increase in rainfall, respectively). Two days after rainfall, lying time rebounded to about 1 h longer than before the rainfall. On the day after the heaviest rainfall event, group average lying time was only 2.5 ± 1.9 h/d (mean ± standard deviation); in 2 groups, 30% and 38% of cows, respectively, did not lie down at all for 24 h. Lying time decreased with deteriorating paddock soil conditions, especially with increasing surface water pooling, suggesting that this may be a useful measure to estimate the quality of the lying surface. Descriptively, ruminating time appeared to decrease with increased surface water pooling, possibly due to decreased lying time. Our results demonstrated that dairy cows could experience periods of short or no lying time during inclement weather and muddy paddock soil conditions. Prior rainfall and surface water pooling may be useful measures to determine if lying time, and thus animal welfare, are compromised.

Despite the clear importance of drinking water, calves are not always provided water on farm for the first few weeks of life. The main objective of this study was to investigate the effects of water provision (access or no access) and milk allowance (high or low) on the behavior and growth rate of calves. Fifty mixed-breed calves were each assigned to 1 of 4 treatments: (1) water and high (10 L/d) milk allowance (n = 13), (2) no water and high milk allowance (n = 12), (3) water and low (5 L/d) milk allowance (n = 12), or (4) no water and low milk allowance (n = 13). Visits to the water trough, water intake, milk drinking behavior (visits and drinking speed), proportion of observations eating hay and calf starter, and lying behavior were recorded from when the calves were, on average, 5 d of age (standard deviation: 2 d) for 4 consecutive weeks. Calves were weighed weekly. Some calves began to visit the water trough from the start of the recording period, as early as 4 d of age, and water intake increased with age for all calves that had access to it. This increase was greater for calves provided a high milk allowance. Water intake increased with ambient temperature, which highlights the importance of providing drinking water in warm conditions. Overall, calves spent a greater proportion of observations eating hay and calf starter with age. The provision of drinking water was associated with a greater proportion of observations eating hay but less eating calf starter. The increase in the proportion of observations eating calf starter with age was greater for calves on a low milk allowance than of those provided a high milk allowance; this is likely due to calves on a low milk allowance searching for nutrients and energy. Calves on a high milk allowance grew faster and spent more time lying compared with calves with a low milk allowance, thus suggesting greater satiety of well-fed calves. Our results suggest that calves should have free access to drinking water from birth and that access to drinking water may aid in hay (fiber) intake and possibly rumen development.

This study aimed to assess the effects of water quality (contamination with manure) on water and feed intake and subsuquent milk production, and lying behaviour in dairy cattle. Fifteen lactating Holstein-Friesian cows were provided one of three water treatments in a cross-over design; clean (tap) water, or water contaminated with either 0.5 mg or 1 mg fresh manure/g water. Cows were managed individually in indoor pens and milk production, feed and water intake (free and via feed) and lying behaviour were recorded daily. Live weight was recorded before and after each treatment exposure. Cows were in their pens for 5 days with clean water (baseline) before given one of the three water treatments for 4 consecutive days. Between each baseline/treatment period the cows were managed as one group on pasture for 5 days with clean water to minimize any carryover effects. This was repeated until all cows had undergone all treatments. Data were analysed using analysis of variance of the 4-day treatment averages and repeated measures analysis of variance to examine day trends within treatment phases. There was an overall treatment effect on free water intake (P < 0.001, SED: 2.34); cows drank more of the clean water (78.0 L/day, range: 49.2?118.0 L) compared to when it was contaminated with 0.5 mg (68.4 L/day, range: 53.5?82.8 L) or 1 mg manure/g water (67.0 L/day, range: 50.6?86.8 L). The water intake of the two contaminated water treatments increased over the 4 days to be the same as the clean water treatment by day 4 (treatment * day interaction, P = 0.002). The cows obtained considerable amount of water from their feed (on average 48 L/day), however, there was no treatment effect on this water intake (P = 0.511). There was no treatment effect on feed intake, live weight or lying behaviour (P ? 0.064). Our results show that cows are sensitive to manure contamination of their drinking water. Cows consumed less contaminated water for the first three days of exposure, however, this was not evident on day four, and the reasons for this are unclear. Water quality did not influence feed intake, production or lying behaviour, however, this could be due to the relatively low levels of contamination used, and/or the high water intake from the feed (cut pasture) may have contributed to meeting metabolic requirements to maintain milk production.

Previous studies have demonstrated that dairy cattle prefer pasture over indoor conditions especially at night-time, which suggests they perceive pasture as an attractive place to rest. Indeed, cows avoid and spend less time lying on hard surfaces, such as concrete or mattresses, compared to softer surfaces. This study aimed to investigate how much time cows spend lying on pasture at the end of summer when the ground can be hard, compared to a softer surface. Four groups of lactating dairy cattle (5 cows/group) had access to either pasture alone or a pasture containing two deep bedded woodchip areas for 9 consecutive days in a cross-over design. Woodchip usage and posture (upright or lying) were recorded using data loggers and video cameras. We also recorded weather conditions, surface characteristics (hardness, dry matter content, temperature) and milk production. There were no consistent significant differences in lying times of cows with or without woodchip bedded areas. Average lying times for groups with access to pasture only and the woodchip were 8.9 h/24 h (range: 7.8-10.1 h) and 8.5 h/24 h (range: 7.6-9.7 h), respectively, excluding milking times. Average number of hours per day on the woodchip was 2.1 h (range: 0-5.9 h), however, there was considerable animal variation in the use of the woodchip bedded areas. When cows were on the woodchip, they spent on average 51 % of their time lying (SEM: 7 %) and when they were on pasture they spent 36 % of the time lying (SEM: 1 %). Most of the lying, however, was on the grass. Both surfaces likely provided cows with a comfortable lying surface despite pasture being harder than the woodchip. Rainfall prior to data collection may have contributed to pasture being unusually soft for the time of year. Overall, lying times decreased with increasing heat load (air temperature, temperature-humidity index, heat load index, P < 0.001) and rainfall (P=0.002). Cows spent less time on the grass and more time on the woodchip as the daily average air temperature increased; for each 1 degrees C increase in air temperature, the time spent on grass decreased by 1.0 +/- 0.46 (SE) percentage points per day (P=0.047). We speculate that this was due to woodchip being a cooler surface or attracting fewer flies than the grass. In conclusion, cows varied in their use of deep bedded woodchip areas when provided in the pasture, however, most of the time spent lying was on the grass.

Body temperature (BT) is widely used to evaluate health and heat load status in cattle. Despite its importance, studies vary in how BT is measured and in the biological interpretation of the results. Costs, practicality, labor, and welfare concerns can affect how BT is measured, including frequency of measurement and the type of device used. Inaccurate BT outcomes may have implications for cattle welfare; for example, animals may only receive treatment when fever is identified. Our objectives were (1) to compare measurement of vaginal temperature (VT) using relatively small, inexpensive, and low-accuracy loggers (±0.5 to ±1°C, iButton range; Embedded Data Systems, Lawrenceburg, KY) to a high-accuracy logger (±0.1°C; StarOddi, Gardabaer, Iceland), and (2) to evaluate how different BT sampling strategies correspond to 24-h VT in lactating dairy cows. To address the first objective, VT data from 54 cows were recorded every 45 min for 12 d/cow, on average, using 2 different types of temperature loggers (StarOddi DST centi-T and iButton DS1921H or DS1922L) attached to a shortened, hormone-free controlled internal drug release insert. Average VT obtained from both loggers were compared using mixed models and regression analyses. In addition, we tested the consistency of the low-accuracy loggers in detecting cows with elevated BT using the kappa coefficient of concordance. To address the second objective, VT data from 20 cows were recorded every min for 9 to 11 d/cow using StarOddi loggers. Using these data, we estimated average VT using 11 sampling strategies (every 5, 10, 15, 30, 45, 60, and 120 min, 1×/d recorded in the morning or afternoon, 2×/d, or 3×/d). Estimates and observed means were compared using linear regression. Compared with StarOddi loggers, the iButtons either underestimated (H model: 38.7 vs. 38.0 ± 0.06°C) or overestimated VT (L model: 38.7 vs. 39.2 ± 0.04°C). When considering elevated or fever VT thresholds, iButtons did not correctly classify animals; kappa coefficients of concordance were ≤0.35. Measuring VT as often as every 120 min resulted in more accurate estimates compared with strategies that recorded it once to thrice per day. These results indicate that the type of device (i.e., data logger) and sampling strategies affect BT outcomes and that these decisions affect the interpretation of BT data.

This study aimed to evaluate the effect of a buccal meloxicam formulation on the behavioural response to ring castration of calves. Sixty, 3-month-old, Angus calves (40 males, 20 females) were allocated to one of three treatments (n = 20 calves/treatment): (1) rubber ring castration (RING), (2) buccal formulation of meloxicam plus rubber ring castration (RING + BUCC) and (3) handled only (CON). After treatment, calves were observed in five pens (n = 4 calves/treatment/pen) and behaviour individually recorded for 1 min every 20 min, until 3 h post-treatment (9 min/calf). Castrated calves (RING and RING + BUCC) spent less time standing (P < 0.001) and more time lying (P = 0.001) than CON calves. RING and RING + BUCC calves were also observed standing in a stretched positon (P = 0.001) and walking abnormally (P = 0.001) more than CON calves. Further, RING and RING + BUCC calves performed more kicks (P = 0.008) and less pawing (P = 0.04) than CON calves. RING + BUCC calves tended to ruminate (P = 0.085) more than RING calves. Ring castration caused behavioural changes in calves indicative of pain, however, administering a buccal formulation of meloxicam to calves immediately before ring castration did not appear to reduce the acute pain response to this procedure. To thoroughly evaluate the efficacy of a buccal formulation of meloxicam on the pain response to ring castration of calves it may be necessary to observe the animals for longer and to investigate the timing of drug administration further.

The aim of this series of studies was to evaluate the behavioral and physiological responses (experiment 1), the electroencephalographic response (experiment 2), and the efficacy (experiment 3) of cryoablation to determine if it could provide an alternative to cautery disbudding (DB) for calves. In experiment 1, at approximately 3 d of age, 58 female Friesian dairy calves were allocated to one of five treatments: (1) control handling (CON, n = 11), (2) cautery DB (n = 11), DB plus local anesthetic (n = 12), DB using cryoablation (CR, n = 12), and CR plus local anesthetic (n = 12). Behavioral and physiological (complete blood cell counts and plasma cortisol concentrations) measures were recorded for up to 4 and 72 h post-treatment, respectively. In experiment 2, at approximately 4 d of age, the electroencephalographic response was recorded in 20 male and female Friesian-cross dairy calves disbudded using cautery (DB, n = 10) or cryoablation (CR, n = 10). In experiment 3, at approximately 4 d of age, 274 female Friesian-cross dairy calves were enrolled from two dairy farms and each calf had one of two treatments randomly assigned to each horn bud: cryoablation applied for 10 s (CR-10, n = 274 buds) or 15 s (CR-15, n = 274 buds). At approximately 6 months of age, calves were checked for scur or horn growth. In experiment 1, DB calves spent less (P < 0.05) time lying than DB plus local anesthetic, CR, and CR plus local anesthetic calves. At 3 h post-treatment, the total white blood cell counts and neutrophil:lymphocyte ratio were higher (P < 0.05) in CR than DB and CON calves. Plasma cortisol concentrations were greater (P < 0.05) 30 min after DB and CR compared with CON; however, concentrations did not differ between DB and CR calves. Cortisol concentrations were greater (P < 0.05) in CR calves 90 min post-treatment compared with all other treatments. In experiment 2, cryoablation elicited increases in median frequency and 95% spectral edge frequency and a decrease in total power, whereas cautery elicited an increase in 95% spectral edge frequency only. In experiment 3, cryoablation successfully prevented horn growth in only 19% and 33% of CR-10 and CR-15 calves, respectively. Spraying liquid nitrogen directly onto the horn bud region appeared to cause more acute pain than cautery DB and did not effectively prevent horn growth. (C) 2019 Elsevier Inc. All rights reserved.

Abstract Feeding behavior can be measured using automated calf milk feeding systems, that record total number of visits consisting of rewarded (milk consumed) or unrewarded (no milk consumed) visits. Unrewarded visits can be either when the calf is entitled to milk, but does not drink (“Entitled”), or is not entitled to milk, so cannot drink (“Non-entitled”). Feeding behavior can be used as an indicator of sickness in calves; fewer unrewarded visits to an automated feeder has been shown to be a sensitive measure of the onset of illness. However, a greater understanding of sickness behavior would aid in early detection of disease in calves. This study aimed to evaluate unrewarded visits prior to signs of clinical illness in calves. Calves were group-housed in pens with an automated feeder from approximately 1 wk of age and examined daily for signs of illness. Of the 74 calves, 16 were diagnosed with neonatal calf diarrhea. To examine the feeding behavior during the 5 days leading up to calves displaying clinical signs of illness, we calculated a robust estimate of the daily rate of change (the Kendall-Theil slope) over this time and used the one sample t-test to test whether the slopes were significantly different from zero. During the 5 days before clinical signs of illness, there was a decrease in unrewarded visits, in accordance with other studies. Interestingly, the proportion of “Non-entitled” unrewarded visits decreased (KT slope = -0.05, P = 0.037) whereas “Entitled” increased (KT slope = 0.04, P = 0.038). These results suggest that during the days leading up to clinical signs of neonatal calf diarrhea, calves may be less motivated to drink even though they are entitled to, possibly due to reduced appetite

Heat stress is widely understood to be an important, practical challenge in dairy production. Two key aspects of managing this challenge on farm are discussed: detecting increased heat load and abating it before consequences occur. We focus on tools for use on farms, based on research and insights from the cows. We suggest that monitoring the responses of mature animals informs best management practices across all types of dairy systems.