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We evaluated the supplementation of different sources of the brown seaweed Ascophyllum nodosum (ASCO) meal on taste preference in dairy heifers during a sequential elimination experiment. Six organic certified Jersey heifers averaging (mean ± standard deviation) 16 ± 1.15 wk of age and 92 ± 9.88 kg of body weight at the beginning of the study were used. Treatments consisted of a ground corn-based concentrate mash without seaweed supplementation (control), or this same concentrate mash supplemented with 57 g/d of ASCO meal obtained from Acadian Seaplants (Acadian Kelp), North American Kelp (SeaLife Kelp), or Thorvin Inc. (Thorvin for Animals). The experiment was conducted with 1 heifer enrolled at a time for 11 d each (n = 66 d total) with the feeding regimens distributed as follows: d 0–2 (adaptation phase), d 3–6 (feeding segment 1), d 7–9 (feeding segment 2), and d 10–11 (feeding segment 3). During feeding segment 1 (d 3–6), the control diet was the most consumed treatment resulting in a total dry matter intake of 22.6 kg followed by Acadian, Thorvin, and SeaLife with 17.7, 13.2, and 11.0 kg, respectively. However, Acadian was selected as the most preferred treatment during feeding segment 1 for a total of 11 d, with control, Thorvin, and SeaLife totaling 8, 3, and 2 d, respectively. In the final ranking of treatments, when all 3 feeding segments were included in the evaluation, Acadian was selected as the first choice by 4 heifers with a ranking of 1.67 points, on a scale ranging from 1 (most preferred) to 4 (least preferred), followed by control (2.50 points), Thorvin (2.67 points), and SeaLife (3.17 points). Overall, the treatments containing Acadian and SeaLife were the most and least preferred, respectively, indicating that heifers were able to distinguish different sources of the same seaweed species based on a taste preference sequential elimination experiment.

This study aimed to assess the preference and use of an artificial shelter in dairy cows managed outdoors at calving during winter. We also evaluated whether this preference would be influenced by weather conditions (rain, air temperature, or wind) or the time of the day at calving. Two weeks before their expected calving date, 18 cows were paired based on body weight, body condition score, parity, and expected calving date. Each pair was assigned to an open paddock (42 m²/cow) with a bare soil surface, high mud content, and access to an artificial shelter until calving. The shelter consisted of a 6 × 3 m metal structure, with 3 sides covered with zinc sheets, a polycarbonate roof, and a thick layer of dry sawdust covering the ground surface. Shelter use and cow behavior inside it (lying and sleeping) were continuously recorded via video and analyzed using continuous observation. Observations were divided into 2 periods: the day before calving (24 to 48 h before calving) and the day of calving (24 h before calving until calving). Ninety-four percent (15/16) of the cows preferred to calve inside the artificial shelter, and this preference was not affected by the time of day or weather conditions. Regardless of the day of study (the day before calving or the day of calving), cows spent approximately 64% of their daily time inside the shelter, and once inside, they spent most of the time lying down. Our findings indicate dairy cows prefer using an artificial shelter as a calving and lying place, suggesting that opportunities for protection should be provided when they are managed outdoors in muddy paddock conditions.

Changes in the environment or novel procedures can result in altered cow behavior during data collection; training is often recommended to ensure accurate data is being recorded. Currently, little is known regarding the habituation of dairy cows during methane emission testing with the GreenFeed emission monitoring system (C-Lock Inc., Rapid City, SD), or how behavior relates to enteric methane emission measurements. Methane emissions were estimated from a total of 202 Holstein dairy cows (120–150 d in milk) housed in tiestalls as part of a larger project. Cows were tested on d 0 (training day) and d 1–5 (test day) for approximately 10 min, during which behavior was recorded by a trained observer. While cows spent more time with their head outside of the machine on the training day (d 0) than during the test days (d 1–5), the opposite pattern was observed for the number of leg movements. No differences in estimated methane production were found over the different days, though it was negatively correlated with both behaviors. These results highlight the importance of habituation of dairy cows to the GreenFeed system for methane measurements to minimize changes to cow behavior under tiestall conditions, whereas the methane emissions themselves are less affected. However, further research is needed to determine the impact of cow behavior on the reliability and repeatability of methane emission measurements as it may introduce bias in genetic evaluations for methane efficiency.

The objectives of this study were to determine the social behavior response to repeated social regrouping (SR), and if social rank and the changes of social rank affect the growth rate and some metabolites and hormones linked to energy status, in “resident” replacement dairy heifers subjected to SR for 205 d. Fourteen dairy heifers (153.3 ± 16.1 kg; 9 to 11 mo old), maintained under grazing conditions, were regrouped every 21 d with 5 new animals (total = 10 SR). Two days after each SR, heifers were weighed and their withers height was measured, and blood samples for nonesterified fatty acids, glucose, and IGF-1 were taken. Concentrations of nonesterified fatty acids, glucose, and IGF-1 were taken. Social behavior was registered by continuous sampling and social status was calculated by the ETlog software, considering the total number of agonistic interactions on 2 d before and 7 d after each SR. A dominance scale was constructed in each SR, and heifers were categorized as high-ranked (HRA), medium-ranked (MRA), and low-ranked (LRA). In addition, the social rank in the first and the last 5 SR were compared, resulting in 3 categories: heifers that remained in the same social rank (Mai), and heifers that lowered (Low) and raised (Rai) their social ranks. Variables were analyzed by repeated measures using a generalized lineal mixed model, considering the social rank in each SR or the change in social rank, the number of SR and their interaction as main effects, and the farm of origin and animal as random effects. Heifers performed more agonistic (2.6 vs. 1.8 ± 0.6, day of SR and 7 d later, respectively) and total (3.8 ± 1.2 vs. 2.5 ± 0.7, day of SR and 7 d later, respectively) interactions on the day of each SR than 7 d after, whereas the number of interactions decreased after the first 2 SR. Medium-ranked heifers presented greater IGF-1 concentrations than HRA heifers at SR1, SR4, and SR9, and than LRA heifers at SR3 and SR4, whereas IGF-1 concentrations were greater in HRA heifers than MRA heifers at SR3 and SR7. In addition, LRA heifers had greater IGF-1 concentrations than MRA ones at SR3 and compared with HRA heifers at SR9. Heifers that lowered their social had greater IGF-1 concentrations than Mai heifers along the SR (132.5 ± 17.1 vs. 97.8 ± 11.2 ng/mL, Low and Mai heifers, respectively) and at SR1, SR3, and SR9. In conclusion, although regrouping animals according to their characteristics can facilitate farm handling, it should be considered that endocrine profile may be affected according to heifers' position in the social hierarchy.

Dairy cattle are gregarious animals that are commonly managed in social groups, yet group-level social dynamics remain underexplored in weaned heifers. We characterized activity and social networks after weaned heifers had been raised in social groups on pasture for approximately 2 mo and examined effects of preweaning social housing. Holstein heifers raised in individual pens (n = 17) or paired pens (n = 20; 10 pens of 2) were mingled between treatments and grouped (10–11 heifers/group; total of 4 groups observed) on pasture following weaning (8.8 ± 0.4 wk of age; mean ± standard deviation). When heifers were 17.8 ± 1.0 (mean ± standard deviation) wk of age, we conducted live observation over a period of 5 d (6 h/observation day; morning: 0800 to 1100 h and afternoon: 1200 to 1500 h) for a total of 30 h observation/group. Using instantaneous scans at 10 min intervals, we recorded behavior (feeding, lying, or standing) and social proximity (<3 body lengths of another heifer, with neighbor identity noted) of all heifers. Duration of lying and feeding did not differ between previous housing treatments, but heifers reared in pairs stood for longer in the morning than previously individually housed heifers (30% vs. 24% of scans; standard error = 0.03). Networks of different behaviors showed limited correlation, with some variability between groups. Centrality in social networks was minimally affected by preweaning social housing, although previously pair-housed calves had greater strength (sum of an individual's edge weights) and eigenvector centrality (sum of the centralities of an individual's connections) in the lying social network for one group. Preweaning pair assignment was correlated with network structure for lying and standing networks for some groups. These results suggest that preweaning social housing may subtly affect activity and social behavior longer-term, but that behavior may be most subject to current social context.

The present study aimed to compare the efficiency of different pens and animal flow configuration layouts in freestall pens using a robotic milking system (RMS) with guided flow based on the behavioral patterns of multiparous lactating Holstein dairy cows in a commercial farm. The behavior of 24 cows in freestall pens was evaluated, divided into 4 different stall configurations: original (OR), conversion (CVS), toll-booth I (TBI), and toll-booth II (TBII), each featuring distinct circulation layouts with different configurations of location, position, and number of guided-flow RMS equipment, feed bunk, water trough, commitment pen, sand beds, sorting gates, and one-way gate. Six multiparous cows, parity 2 or 3, with an average (± SD) of 180 ± 20 DIM, were randomly selected from each freestall pen for focal assessment of behavioral patterns. The location, position, and behavior of each animal were recorded in a field ethogram, with individual sequences recorded at 15-min intervals using the focal method during 6 nonconsecutive 10-h periods in each pen, and the proportion of observed time for each behavior was assessed. The pens differed in the number of available milking robots (1, 2, or 3), the number of animals per robot, the quantity and orientation of smart doors, and the placement of feed bunks, water troughs, and sand beds. A completely randomized experimental design was used to compare the 4 stalls, with a nonparametric Kruskal-Wallis test, in which the medians of the treatments were then compared with the Dunn test at a significance level of 5%, using the Minitab software. The behavioral pattern of cows exhibited differences based on the stall configuration with RMS as a proportion of the observed time (60 h). The TBI stall configuration, where the animal needs to be milked to exit the milking robot, showed a higher percentage of observed time spent in the sand bed (68%) and lying position (64%) compared with other stalls, as a proportion of the observed time (60 h). Notably, the TBII stall exhibited a significant amount as a proportion of observed time (60 h) in the holding area (16%), possibly attributed to a layout with a higher number of animals per robot, emphasizing the importance of respecting the number of animals per robot when housing in a stall with RMS. Thus, spatial configuration and the density of robotic systems are factors that influence the behavioral pattern of dairy cows.

Personality affects the behavior of dairy cows in response to various situations on farm, such as novel or social challenges, which can affect the welfare of individual cows. Personality traits are evaluated through behavioral testing, typically in unfamiliar environments, but this can be a time-consuming process. Using a novel object test (NOT) and a forced human approach test (FHAT), we tested 222 individual dairy cows and retested a subset of cows (n = 78) 8 mo afterward. The aim was to see if personality traits can be identified in a familiar environment and if traits were consistent in between test and retest. Principal component analysis was used to identify personality traits. Extracted components (personality traits) were named according to determining variables (loadings <−0.63 or >0.63). Based on identified personality traits we calculated the intraclass correlation (ICC) coefficient and the differences between personality trait in test and retest to assess consistency. We identified 3 personality traits from NOT measurements (“explorative,” “boldness,” and “sociable”) explaining 85% of the variance and one trait from behavioral measurements in the FHAT (“trusting”) explaining 74% of the variance. Mean ICC of 0.6 with a standard deviation of 0.18 shows that although traits are consistent at herd level, cows react individually in stressful situations. As both tests were carried out in a familiar environment and results are similar to other studies that used unfamiliar environments, we can conclude that tests can be performed in a familiar environment.

There is currently societal interest and concern for dairy cow welfare. It has been suggested that boredom poses a welfare issue for dairy cows, particularly when presented with extended disposable time in housed environments that lack stimuli. Farm animals experience a multitude of affective states, which has created a need for positive experiences to be included in welfare management. Environmental enrichment can reduce boredom and facilitate positive experiences; however, the research in cows is limited. To assess the behavioral impact of a simple enrichment on commercially housed dairy cows, we provided 24-h access to a novel object, for 3 wk, for 2 separate groups of cows. Two boredom-associated behaviors significantly decreased when the object was present compared with when it was not present: “idling” behavior and unsuccessful robotic milking attempts (“refusals”). In addition, there was a significant increase in the occurrence of self-grooming during treatment weeks, when the novel object was present. These results suggest that idling and refusals may be behavioral indicators of boredom in dairy cows.