Biology subjects

Cellier, M.

Publications and source records attributed to Cellier, M..

4 recordsLinked to original sources

bioRxiv2026

Validation of behavioural tests for personality assessment in tie-stall dairy cows

The study of animal personality has gained increasing attention in recent years, as researchers recognize that non-human animals exhibit stable individual differences in behaviour. In dairy cattle, understanding personality traits holds potential for improving animal welfare, enhancing management practices, and supporting productivity outcomes. However, validating the behavioural tests used to assess these traits remains a significant challenge. The present study aimed to evaluate the consistency and validity of five commonly used behavioural tests in dairy cows: the Human Approach Test (HAT), Sudden Test (SUD), Novel Object Test (NOT), Open Field Test (OFT), and Novel Surface Test (NST). These tests were chosen for their potential to assess personality dimensions that parallel components of human personality, particularly Openness, Neuroticism, Extraversion, and Agreeableness. Repeated assessments were conducted across three time periods to evaluate both intra-test (temporal) and inter-test (contextual) consistency. Results revealed that only the SUD exhibited significant behavioural consistency across all periods, suggesting its potential as a reliable tool for personality assessment. Additionally, a moderate correlation between the HAT and SUD was observed, indicating that these tests may capture overlapping personality traits. In contrast, the remaining tests (NOT, OFT, NST) lacked consistent behavioural patterns over time and across contexts, raising questions about their reliability and the complexity of trait expression. These findings highlight the challenges of identifying stable personality traits in cattle and emphasize the need for more rigorous validation of behavioural tests. This research contributes to the growing field of animal personality by providing insights into trait stability, the limitations of current testing methods, and the potential application of personality assessment in future livestock management practices.

animal behavior and cognition↗

bioRxiv2026

Investigating cognitive enrichment for dairy calves through behavioral measures of participation and engagement: a pilot study

Introducing cognitive enrichment from an early age has the potential to enhance an animals capacity to learn both simple and complex tasks, promote neural plasticity, and support cognitive development. This is applicable for young cattle who are at a critical stage in their development and could benefit from the influence cognitive enrichment has on their behavioral expression. This study aims to explore the effects cognitive enrichment has on weaned dairy calves through analyzing behavioral measures of voluntary participation and short-term behavioral reactions to enrichment exposure. Our study involved a total of five pairs of weaned calves (n=8 treatment; n=2 control). The treatment groups were presented with three variations of a puzzle box, each equipped with unique challenges that offer different solutions (push, slide, pull). These boxes were provided to the calves twice daily over the span of nine days in an isolated corridor located behind their pen. We hypothesized that motivated calves would consistently engage with cognitive enrichment voluntarily over time and express directed natural behaviors, reflecting sustained participation across repeated trials. Results demonstrated that calves consistently visited the cognitive enrichment area across trials, with an average latency of 75.7 {+/-} 47.0s from the pen to the enrichment. Secondly, the calves spent a significant proportion of trial time within the enrichment area at 65% (870.1 {+/-} 21s). Lastly, all calves expressed a broad range of behaviors in line with their natural exploration within the enrichment area, while the puzzle box treatment groups expressed higher durations of behavioral expressions when compared to the control (F=11.7, p<0.0001). Combined, these results indicate the calves motivations to voluntarily participate in a cognitive challenge. While these are promising findings for cognitive enrichment and its applicability to dairy calves, further work is needed to understand broader parameters. Specifically, how can social dynamics influence enrichment interaction in groups, how can this type of enrichment be implemented on farms, and what are the long-term effects to providing cognitive enrichment in the early stages of development.

zoology↗

bioRxiv2026

Responses of dairy cows following a change in housing system and social group: a living lab experiment

To investigate how the disturbances associated with a relocation to a bedded-pack barn, such as a housing system change, a milking system change and a social regrouping, impacts the behavior of lactating dairy cows, 38 cows from a total of 9 tie-stall or free-stall commercial farms were moved to a newly built bedded-pack barn on an enrollment basis, with a social regrouping occurring after 2 weeks. Scan sampling of video data was done to assess behavior expression in the pen, and live data was collected to assess milking reactivity and animal handling procedures. Results indicate that the cows adapted quickly to the relocation to the new housing system as there were no changes in the locations in the pen, the body positions or the behaviors of cows in time between arrival and regrouping. The social regrouping had a bigger impact with a decrease in 16% of the observed time spent lying and an increase of 9.7% of the observed time spent feeding. Cows also adapted quickly to the milking procedures with a rapid decrease in the occurrence of negative social interactions between cows at the parlor, and in needing less human-animal manipulations and less time to be brought to the parlor. The housing system of origin had a slight effect on behaviors with cows from tie-stalls spending 1.7 times more of the observed time lying than free-stall cows, and free-stall cows spending 1.6 times more of the observed time feeding than tie-stall cows. This study provides a better understanding of how dairy cows respond to disturbances and is encouraging for producers that need to make changes to their current housing system as cows were shown to be quickly adaptable to the challenges presented to them. SummaryDairy cows from cubicle systems were shown to adapt quickly after a relocation to a bedded pack barn, the first use of a milking parlor, and a social regrouping. This was supported by limited changes observed in their behaviors after the disturbances, and observed deviations were temporary and short-lived. Animal handling procedures also observed a quick improvement in time with the trips to the milking parlor needing 2x less time and 3.5x fewer physical contacts from handlers after 5 days. These results are encouraging to producers needing to make changes to their barns.

zoology↗

bioRxiv2017

CYRI1-mediated inhibition of RAC1 signalling restricts Salmonella Typhimurium infection

Salmonella presents a global public health concern. Central to Salmonella pathogenicity is an ability to subvert host defence mechanisms through bacterial effectors that target key host proteins implicated in restricting infection. Thus, to gain insight into host-pathogen interactions governing Salmonella infection, a thorough understanding of host defence mechanisms is needed. To tackle this, we performed an in vivo genome-wide ENU mutagenesis screen to uncover novel host defence proteins. Through this screen we identified an uncharacterised protein, which we name CYRI1 (CYFIP-related RAC1 Interacting protein 1) that serves as a Salmonella resistance factor. We show that CYRI1 binds to the small GTPase RAC1 through a conserved domain present in CYFIP proteins, which are known RAC1 effectors that stimulate actin polymerisation. However, unlike CYFIP proteins, CYRI1 negatively regulates RAC1-driven actin cytoskeleton remodelling, thereby attenuating processes such as phagocytosis and cell migration. This, in turn, enables CYRI1 to counteract Salmonella at various stages of infection, including bacterial entry into epithelial cells, internalisation into myeloid-derived phagocytes as well as phagocyte-mediated bacterial dissemination. Together, this outlines a novel host defence mechanism that is crucial for determining bacterial fate.

cell biology↗