JDS communications最新文献

{"title":"Interaction between drinker density and cow social dominance affects drinking behavior","authors":"","doi":"10.3168/jdsc.2023-0479","DOIUrl":"10.3168/jdsc.2023-0479","url":null,"abstract":"<div><p>Dairy cow welfare and milk production levels can be negatively affected when animals lack access to sufficient amounts of good-quality drinking water. Farms vary greatly in how well they meet this standard. Here, we explored how the interaction between drinker density and social dominance level influenced the drinking behaviors of a group of 40 mid-lactation cows. We recorded cow drinking behavior and competitive outcomes (i.e., number of replacements) at the drinkers during the final 5 d of 2 drinker density treatments, applied successively (12 drinkers, then 4 drinkers available). Four social dominance categories were defined by applying the quartile classification method to the normalized David's score obtained from the low-density treatment data (NormDS values). The high- and low-density treatments used approximately 56 (±16) versus 119 (±31) replacements per drinker per day. Subordinate cows were lighter and younger than dominant cows. Dominant cows drank around 5 L more per day in the low- versus high-density treatment. Furthermore, both drinking rate and daily drinking frequency were higher in the low-density treatment, with the most pronounced differences seen for subordinate cows. In the low-density treatment, mid-subordinate cows shifted their drinking times, visiting the drinkers 1 to 2 h after peak water consumption by the group. The results for the low-density treatment thus indicate that the cows were experiencing more intense competition for water, leading to behavioral responses that were related to social dominance. Our findings underscore the need to more broadly explore the effects of increasing drinker numbers under a variety of rearing conditions to provide farmers with better technical recommendations.</p></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 5","pages":"Pages 400-405"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666910223001394/pdfft?md5=89564919f2b4c447a81df16774e46d42&pid=1-s2.0-S2666910223001394-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138614223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adding behavior traits to select for heat tolerance in dairy cattle","authors":"","doi":"10.3168/jdsc.2023-0421","DOIUrl":"10.3168/jdsc.2023-0421","url":null,"abstract":"<div><p>The increase in periods of heat waves leads to an increase in heat stress events in dairy cattle leading to welfare issues, production losses, and health issues. However, the low frequency of milk recording data makes genetic evaluation for heat tolerance still a challenge. A possible solution could be to add behavior data captured through sensors which are recorded permanently, mostly reported on a daily basis. The objective of this study was to evaluate the potential gain of adding behavior traits as proxies for genetic evaluation of heat tolerance. Behavior traits including activity time (ACT), rumination time (RUM), and eating time (EAT) were recorded for 453 Holstein cows equipped with SenseHub (Allflex Livestock Intelligence) collars from October 2019 to July 2022 in 6 herd located in the Walloon Region of Belgium. A multitrait reaction norm model based on separate temperature and humidity index (THI) thresholds was used. Results showed that behavior traits present not only interesting characteristics for genetic evaluation of heat tolerance but also for heat stress detection in farms. Indeed, sensors allow recording of behavior for all events of heat stress in lactating and nonlactating animals. Moderate heritability values were also found for the behavior traits (0.14 for ACT, 0.19 for RUM, and 0.12 for EAT), and a high ratio between the general and thermotolerance additive genetic variances was obtained. In addition, positive correlations of thermotolerance for ACT and EAT with thermotolerance for milk production (fat- and protein-corrected milk: 0.45 and 0.28, respectively) and negative genetic correlations of thermotolerance for ACT with somatic cells (somatic cell score: −0.39) were estimated. The genetic correlation matrix allows us to explain a high part of the variation for the reaction to heat stress of 2 economic traits (fat- and protein-corrected milk: 59% and somatic cell score: 31%) based on behavior data. Based on these results, behavior traits could be used to assess heat stress in nonlactating cattle for which the number of genetic evaluations for heat tolerance is still limited.</p></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 5","pages":"Pages 368-373"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666910224000024/pdfft?md5=8f03e7a308fbedd1266f2ccae054d817&pid=1-s2.0-S2666910224000024-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139540558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differences in standing behavior between Jersey and Holstein dairy cows during the periparturient period","authors":"","doi":"10.3168/jdsc.2023-0502","DOIUrl":"10.3168/jdsc.2023-0502","url":null,"abstract":"<div><p>Jerseys are the second most popular breed in the US dairy industry, yet there are few studies that directly compare their behavior with Holsteins. The objective of this observational study was to describe differences in the standing behavior of healthy Jersey and Holstein dairy cows during the periparturient period. A total of 51 Jerseys (11 primiparous [PP] and 40 multiparous [MP]) and 36 Holsteins (8 PP, 28 MP) were used for this analysis. Data loggers that measured leg orientation were used to determine daily standing time (min/d), number of standing bouts (no./d), and standing bout duration for each cow from approximately 3 wk before until 4 wk after calving. Holstein and Jersey cows were commingled throughout the periparturient period and only healthy cows were included in the analysis. Overall, Jerseys had longer standing times and longer standing bout durations compared with Holsteins during the period before calving. On the day before calving, PP cows had longer standing times than MP cows, but there was no effect of breed on standing behavior during the calving period (d −1, 0, and +1 relative to calving). The number of standing bouts for all cows spiked on the day of calving, but this increase was greatest for the MP cows, regardless of breed. Primiparous cows had longer postpartum standing times compared with MP cows; however, PP Jerseys tended to have the longest daily standing times during the first 10 DIM. After calving, there were no breed differences in the number of standing bouts per day among MP cows; however, PP Jerseys had more standing bouts than PP Holsteins during this time. Understanding how Jersey and Holstein behaviors differ may offer insights into better management of Jerseys during the period around calving.</p></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 5","pages":"Pages 479-483"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S266691022400036X/pdfft?md5=88ee9f83820fa91706a4610bc5660cbc&pid=1-s2.0-S266691022400036X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140090430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seeing through the smoke: The effects of wildfire fine particulate matter (PM2.5) exposure on standing and lying behavior in Holstein heifer calves","authors":"","doi":"10.3168/jdsc.2023-0503","DOIUrl":"10.3168/jdsc.2023-0503","url":null,"abstract":"<div><p>Wildfires are burning more acres annually, contributing to air pollution across the United States. Air pollutants, such as particulate matter (PM_2.5), have health implications for humans and animals, and are known to alter behavior in several species, but effects of wildfire PM_2.5 on dairy calf behavior are unknown. The present study aimed to understand how dairy calf standing and lying behavior is affected by wildfire PM_2.5. Holstein heifer calves (n = 13) were monitored for the first 90 d of life, concurrent with the 2022 wildfire season. Hourly PM_2.5 concentrations and meteorological conditions, which were used to calculate temperature-humidity index (THI), were recorded. Wildfire and wind trajectory mapping was used to determine the contribution of wildfires to spikes in PM_2.5. Calf activity data were recorded every minute using accelerometers and analyzed as total hourly and daily standing and lying times, standing and lying bouts, and duration of bouts. Additionally, the responses of calves to the initial 24-h period of each of 2 separate exposures to wildfire smoke were assessed. Wildfire PM_2.5 exposure was associated with reduced daily standing time and bout duration, increased daily total lying time, and increased, albeit not significantly, daily standing bouts. Percent of time standing hourly was increased, whereas percent of time lying hourly was decreased by wildfire PM_2.5. The initial 24 h of each smoke exposure was characterized by decreased standing and increased lying time, but there was a greater change in behavior during the first event compared with the second event. These results indicate that exposure to wildfire PM_2.5 induces a behavioral response, which may diminish with repeated exposures. Future research should aim to understand the health and welfare implications of the behavioral responses to wildfire PM_2.5.</p></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 5","pages":"Pages 490-494"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666910224000474/pdfft?md5=761d3d2e7c632c71ff592e4dbec28c7c&pid=1-s2.0-S2666910224000474-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140404567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grazing behavior of dairy cows under contrasting pasture allocation frequencies and areas","authors":"","doi":"10.3168/jdsc.2023-0478","DOIUrl":"10.3168/jdsc.2023-0478","url":null,"abstract":"<div><p>This study aimed to compare grazing behavior of dairy cows with highly contrasting pasture allocation frequencies. The study ran from September 9, 2022, to December 2, 2022 (12 wk), during a time when daily pasture growth was expected to exceed daily herd intake. Three pasture allocation frequencies were compared, each with 11 spring-calving cows grazing a 4-ha farmlet. The allocations were high frequency rotational grazing (HFRG; 32.5 m²/cow per allocation and 4 allocations/d), rotational grazing with weekly allocations (7RG; 909 m²/cow per allocation and each allocated area continuously grazed over 7 d), and continuous grazing (CG; 1,818 m²/cow per allocation). Animal behavior was monitored using IceQube accelerometers (Peacock Technology) and CowManager ear tags (Agis Automatisering BV). Milk yield and composition were measured and pasture cover was estimated. Daily eating time was highest for CG animals, whereas lying time, lying bouts, and ruminating time were lowest, with no differences between HFRG and 7RG. There were no differences in fat- and protein-corrected milk yield between farmlets; however, estimated accumulated pasture yield was greater with more frequent allocations. Although milk production did not differ between treatment groups, this appeared to be achieved through greater eating times when allocated pasture less frequently, at the expense of time spent lying.</p></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 5","pages":"Pages 436-440"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666910224000280/pdfft?md5=39204f0431336c7fff7a88f16bf78658&pid=1-s2.0-S2666910224000280-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140462799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring factors influencing machine milk yield of dairy cows in cow-calf contact systems: Cow behavior, animal characteristics, and milking management","authors":"","doi":"10.3168/jdsc.2023-0480","DOIUrl":"10.3168/jdsc.2023-0480","url":null,"abstract":"<div><p>The objective of this study was to explore factors contributing to low machine milk yield of cows with cow-calf contact. Danish Holstein dairy cows were assigned to 1 of 3 cow-calf contact treatments: full-time with the calf (n = 24), part-time with the calf between morning (a.m.) and afternoon (p.m.) milking and separated overnight (n = 23), or separated from the calf at birth (n = 23). Behavior of cows (stepping and kicking in the parlor) and milking procedures (teat or udder stimulation frequency, preparation duration) were recorded at a.m. and p.m. milking on 2 d during wk 4 and 6 of the treatment period (8 milkings per cow). Full-time cows had the lowest machine milk yields (mean ± SE; 6.1 and 6.0 ± 0.7 L at a.m. and p.m. milking, respectively), whereas part-time cows had similar yield to no-contact cows at a.m. milking (19.6 ± 0.7 L) and similar yield to full-time cows at p.m. milking (6.4 ± 0.7 L). Lower machine milk yields in cows with calf contact could not be fully attributed to milk consumption by the calf; however, they also could not be explained by differences in cow parity, calf sex, milking procedures (stimulation frequency; preparation duration), or stepping and kicking (restless) behavior at milking. All cows showed more restless behavior at p.m. milking, which weakly negatively affected machine milk yield, but this was unrelated to stimulation frequency in cow-calf contact cows, indicating that there may be other sources of discomfort or stress at the time of milking for these cows. Part-time versus full-time calf contact improved daily machine milk yields, but low machine milk yield issues merit further research so that cow-calf contact systems can be sustainable for producers.</p></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 5","pages":"Pages 495-499"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666910224000656/pdfft?md5=7133db5d4e736b2040dd69f2f8230daa&pid=1-s2.0-S2666910224000656-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140793109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early pain experiences in dairy calves on pain sensitivity later in life","authors":"","doi":"10.3168/jdsc.2023-0420","DOIUrl":"10.3168/jdsc.2023-0420","url":null,"abstract":"<div><p>In humans, early painful experiences can increase pain sensitivity later in life, but little is known regarding this phenomenon in cattle. This study assessed if a painful event early in life affects later pain sensitivity in 40-d-old calves. Holstein calves (n = 26) were randomly assigned to control or treatment conditions, blocked within sex and birth weight. At 9.5 ± 1.8 d old, treatment calves had 1 horn bud disbudded using caustic paste, whereas control calves had 1 horn sham disbudded; in both cases, multimodal pain control was provided. All calves had the contralateral horn bud disbudded using a hot iron 4 wk later, again with multimodal pain control. Mechanical nociceptive responses were assessed weekly using an algometer applied adjacent to both horn buds and on the rump, beginning 3 d before the first disbudding and ending 30 d after the second disbudding. Following the second disbudding, both groups of calves showed evidence of increased sensitivity (i.e., algometer pressure declined 3.69 ± 0.60 √N to 2.13 ± 0.70 √N) on the contralateral bud, but there was no difference between the control group and the treatment groups. An interaction between treatment and time, likely driven by treatment differences, was found on the rump when tested 5 h after the second disbudding event. These responses are not consistent with the hypothesis that an early pain experience results in increased sensitivity to later painful experiences.</p></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 5","pages":"Pages 390-394"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666910223001126/pdfft?md5=2081b5c34726a58574cb4b348076a049&pid=1-s2.0-S2666910223001126-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139303948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Milk consumption and behavior of calves in automated calf feeders as early indicators of weaning liveweight","authors":"","doi":"10.3168/jdsc.2023-0488","DOIUrl":"10.3168/jdsc.2023-0488","url":null,"abstract":"<div><p>Modern intensive dairy farming relies on data to aid and prioritize management decisions made on farm. Decisions made early in an animal's life can have lasting effects on welfare, productivity, longevity, and profitability. Precision technology such as automated calf feeders (ACF) allow the customization of feeding programs, but despite this, weaning weights (WWT) vary substantially between calves. This observational study used a 3-yr dataset comprising 1,440 female Holstein Friesian calves at a single intensive commercial dairy farm (Dairy Australia feeding system 5; indoor, total mixed ration) using ACF to (1) determine the variability in WWT (as a proxy of animal performance) of calves within this system; (2) identify the contributing factors responsible for the variation in WWT; and (3) identify potential early management intervention points that could be indicative of the performance of calves at weaning within the system. Calves entered the ACF at 10 d of age with 12 calves per ACF; calves were weighed at birth and weaning using weigh scales. We discovered a large range of calf WWT (41–118 kg/head) at ~60 d of age despite the application of strict uniform management protocols. Our results from modeling showed that WWT was significantly and positively associated with birth weight (BWT), with low BWT calves (&lt;36 kg) achieving an average of 70 kg weight at weaning. In contrast, heavier BWT (&gt;36 kg) calves achieved an average of 82 kg at weaning. Based on calf feeder data, cumulative milk consumption and cumulative unrewarded visits to the feeder, as well as BWT, were identified as indicators of greater WWT as all these were highly significant terms in the model for WWT. Results suggest that quantifying consumption and number of visitations to the ACF at d 5 may allow farmers to identify, with time to intervene, calves underperforming within the feeder or system, therefore increasing their potential for growth. Additionally, this demonstrated that greater milk consumption (&gt;30 kg) and interaction with the feeder up to d 5 in the feeder is more likely to yield a WWT &gt;75 kg, identifying a potential point for management intervention for calves below consumption and interaction thresholds (e.g., by developing alarm systems based on consumption or visitation number).</p></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 5","pages":"Pages 474-478"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666910224000346/pdfft?md5=a7bb495e3e8ea435a6cb21f94e9f2161&pid=1-s2.0-S2666910224000346-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140089295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automated, longitudinal measures of drinking behavior provide insights into the social hierarchy in dairy cows","authors":"","doi":"10.3168/jdsc.2023-0487","DOIUrl":"10.3168/jdsc.2023-0487","url":null,"abstract":"<div><p>Dairy cows compete for feed and water access on commercial farms. In this study we used EloSteepness to assess the summed Elo winning probabilities (i.e., dominance) of 87 cows housed in a dynamic group and compared the resulting social hierarchies based on their steepness (i.e., the average degree of differences in winning probability between adjacently ranked individuals in the group, ranging from 0 to 1). We identified a hierarchy at the drinker with a steepness of 0.55 ± 0.02 (SD), whereas the hierarchy detected at the feeder during the same time period was 0.45 ± 0.02, indicating smaller dominance differences among cows when competing for feed compared with competing for water. Individual cows' winning probabilities at the feeder and drinker were moderately correlated (r_s = 0.55), and cows at the lower and upper ends of the hierarchy showed good agreement. We compared the drinker hierarchy between hot (i.e., temperature-humidity index [THI] ≥72) and normal (i.e., THI &lt;72) periods. The hierarchy steepness was similar in both hot (0.54 ± 0.03) and normal conditions (0.56 ± 0.03), and there was a strong correlation in cows' individual winning probabilities across these periods (r_s = 0.87). Cows with higher winning probability visited the drinker less frequently (hot: r_s = −0.40, normal: r_s = −0.33) but had a higher average daily water intake (hot: r_s = 0.38, normal: r_s = 0.37). We also found evidence that individual cows' drinking times differ depending on their winning probability; cows with lower winning probability shifted their drinking times to before or after the visit peak after milking. Automatically identifying cows with consistently high or low winning probabilities using drinkers may help inform grouping decisions and water provision on farms.</p></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 5","pages":"Pages 411-415"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666910223001400/pdfft?md5=c2c6a631454e40687d6c6646e3116925&pid=1-s2.0-S2666910223001400-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138624506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of debonding on stress indicators in cows and calves in a cow-calf contact system","authors":"","doi":"10.3168/jdsc.2023-0468","DOIUrl":"10.3168/jdsc.2023-0468","url":null,"abstract":"<div><p>Premature separation, entailing a mixture of stressful events, follows a period of cow-calf contact in dairy production. We hypothesized that timing and length of debonding (i.e., gradually adapting cow and calf to separation) may affect behavioral responses indicating stress and reinstatement of the cow-calf bond. Initially, cows had 24 h/d smart-gate access to their calves before reduction to 12 h/d, 6 h/d, and finally 0 h/d, either commencing at 4 wk after birth over 28 d: long debonding (LDB, n = 16 pairs), or at 6.5 wk, over 10 d: short debonding (SDB, n = 14 pairs). We aimed to compare the vocal response (high- and low-pitched vocalizations) and proximity (&lt;1 m to separation barrier) of LDB versus SDB cows and calves at each reduction of access and finally at 0 h/d contact. We also aimed to assess the impact of calf supplemental milk intake on their vocal behavior. Direct observations (2 h × 2 d) were performed during the following different phases: 24 h/d access (baseline, BL24h), once cow access was reduced (separation, SEP12h), once pairs were habituated to the change (BL12h), after cow access was further reduced (SEP6h), once pairs were habituated (BL6h), and at 0 h/d contact (SEP0h). Mixed effect linear regression models indicate that overall, treatment did not affect cow behaviors nor the main indicator of separation stress, high-pitched vocalizations. Both calves and cows responded with vocal and reinstatement behavior once cows' access was reduced, with great individual variation. The LDB calves spent less time close to separation barrier and emitted more low-pitched vocalizations. Otherwise, the effect of treatment differed with phase: SDB calves emitted more high-pitched vocalizations in response to the initial reductions of cow access than LDB calves. The LDB cows (but not calves) produced more high- and low-pitched vocalizations when access was reduced to 6 h/d and 0 h/d. Calves drinking &gt;1.5 L of supplemental milk/d emitted fewer high-pitched vocalizations. In conclusion, a longer debonding period initiated at a lower age before separation may alleviate the initial behavioral response to separation, especially for calves. The vocal response of calves increases with age at separation but is modulated by intake of supplemental milk. For cows, our results indicate that the studied debonding methods affected the behavioral response to separation only to a limited degree.</p></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 5","pages":"Pages 426-430"},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S266691022400005X/pdfft?md5=77922f59ba3f7929c789fdbff7fe8ae5&pid=1-s2.0-S266691022400005X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139638043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}