Early-life contact with non-maternal adult cows and a pasture-based rearing environment influence behavioural responses of dairy heifers to novelty.

The complexity experienced in early life can affect trait development of individuals, including sociability and fearfulness. The modern dairy calf's rearing environment often lacks environmental and social complexity. This study examined the effects of early-life, non-maternal adult contact and access to a physically complex environment on the responses of dairy heifers to several stressors, including restraint, social isolation, and novelty at 18 months of age. From the age of 2-13 weeks, 60 dairy heifers (Bos taurus) were reared according to one of three treatments applied to 20 calves each: (1) Hand-reared at pasture in groups of ten, with three unrelated dry cows (+S); (2) Hand-reared at pasture in groups of ten (-S); or (3) Hand-reared in sheds in groups of 10-12 as a commercial control (CC). At 13 weeks, all treatment groups were mixed and managed at pasture as a single herd. At 18 months, the responses of 50 heifers to restraint in a crush, social isolation and a novel object were observed (+S = 16, -S = 17, CC = 17). Treatment did not influence responses to restraint or social isolation, but influenced some indicators of fearfulness during exposure to a novel object. Six +S heifers interacted with the novel object compared to 0 -S and one CC, and CC heifers spent around 50% more time in vigilance than +S or -S heifers. Dairy heifers provided with early-life social enrichment in the form of non-maternal adult contact may have reduced fear of novelty. The implications for lifelong ability to adapt to novel situations, such as entry into the milking herd, should be assessed.

Contact with Mature Cows and Access to Pasture during Early Life Shape Dairy Heifer Behaviour at Integration into the Milking Herd.

This study aimed to determine the effects of early-life physical and social enrichment on the ability of dairy heifers to integrate into a herd of mature cows. Fifty heifer calves were reared from the ages of 2-13 weeks in one of three treatments: (1) Hand-reared and group-housed in sheds (CC); (2) Hand-reared and group-housed at pasture (-S); or (3) Hand-reared and group-housed at pasture, with 3 non-familial dry cows per group (+S). At 23 months of age, these heifers were introduced in groups to small herds of cows (Cows) at pasture. Social interactions were recorded continuously for two 1-h periods. Feeding, ruminating and resting behaviours of all animals and walking, standing and lying behaviours of 36 heifers only (+S = 14, -S = 13, CC = 9) were recorded for 48 h after mixing. Heifers that were managed as calves according to the CC treatment delivered less agonistic behaviour to other heifers after mixing than those reared in the +S or -S treatments (p = 0.002 and p = 0.041, respectively). On Day 2, +S heifers and cows spent the lowest proportion of time feeding (p = 0.961), with -S heifers spending significantly more time feeding than cows (p = 0.046), while CC heifers spent more time feeding than both +S heifers and cows (p = 0.027 and p < 0.002, respectively). Increasing the complexity of the early-life environment, particularly socially, may aid heifers in integrating into groups of multiparous cows later in life and shape their lifelong social experiences with same-age conspecifics.

Enhancing foci on breast MRI: Identifying criteria that increase levels of suspicion.

OBJECTIVE: Prior studies evaluating features of foci associated with malignancy have not been conclusive. This study evaluates foci that were deemed suspicious and assesses multiple imaging and clinical findings with the goal of identifying criteria that can increase diagnostic confidence when evaluating foci on breast MRI. METHODS: After Institutional Review Board approval, a retrospective chart review was performed to identify patients who underwent an image-guided biopsy of an enhancing focus. To be included in the study, a breast MRI performed between 2012 and 2019 must have been classified as suspicious for an enhancing focus or foci, and a biopsy using imaging guidance must have been subsequently performed. Patient and imaging characteristics as well as the corresponding biopsy results were recorded and statistically analyzed. RESULTS: There were 74 patients with 85 foci of enhancement who underwent biopsy within the study period. Thirteen of the 85 foci yielded malignant results for an overall positive predictive value of 15.3% (95% confidence interval: 7.7-22.9%). Additionally, twenty-six of the 85 cases (30.6%) yielded high risk lesions. There was a statistically significant negative correlation between screening breast MRIs and biopsies that yielded cancer or atypia (p = 0.04). There was also a significant association between foci and malignant results if the focus was in the same quadrant of a known malignancy (p = 0.001). CONCLUSION: Clinical information, such as the indication for a breast MRI or the location of a focus relative to a known cancer, can play an important role in evaluating foci of enhancement. Diagnostic confidence in identifying suspicious foci can be aided by incorporating clinical context with imaging findings deemed suspicious by prior research studies.

Distraction, the desire to eat and food intake. Towards an expanded model of mindless eating.

This study compared the impact of different forms of distraction on eating behaviour with a focus on the mechanisms behind this association and the link between the amount consumed and changes in the desire to eat. Participants (n=81) were randomly allocated to four conditions: driving, television viewing, social interaction or being alone in which they took part in a taste test. Measures of the desire to eat (i.e. Hunger, fullness, motivation to eat) were assessed before and after the intervention. The results showed that those watching television consumed more than the social or driving conditions. Food intake was associated with a decreased desire to eat for those eating alone, but was unrelated to changes in the desire to eat for those driving. Watching television also created a decrease in the desire to eat commensurate with food intake whereas social eating resulted in the reverse relationship. The results are discussed in terms an expanded model of mindless eating and it is argued that eating more requires not only distraction away from the symptom of hunger but also sufficient cognitive capacity left to attend to the process of eating.