The effect of early housing and companion experience on the grazing and ruminating behaviour of naïve heifers on pasture

Current research considering social behavior to improve the welfare of commercially raised dairy calves

Social contact in early life has broad benefits for behavioral development and welfare of the developing dairy calf. The most accessible approach to providing social contact for commercially raised dairy calves is rearing calves in same-age groups, a practice that is growing in popularity. This symposium review highlights developing areas of research relevant for widespread implementation of social housing on commercial farms. I discuss the onset of social behavior in young calves, development of social preferences, implications of calf management and housing for expression of social behavior, individual differences in social behavior, and implications of environmental complexity within the context of social housing. Under both naturalistic and commercial settings, calves interact socially within the first days of life and develop preferences for familiar social companions. Early introduction to social housing appears to benefit the development of social behavior, which may affect integration in later social groups, with potential long-term effects. Housing and management factors affecting socially housed calves have potential to disrupt social synchrony compared with behavior under more natural conditions, which can reduce social lying, cause competition for access to feed, and may have implications for social bond formation and social learning within the social group. Although calves exhibit preferences for familiar individuals and motivation for social synchrony, social behavior is also widely variable between individuals and over time. Individual differences in social behavior may be attributed to personality as well as transient states such as disease or pain, and accommodating individual preferences for social interaction or isolation may be important within groups of larger calves. Throughout this paper, I contrast behavior of commercially raised calves in social housing with behavior of calves under more naturalistic conditions and address both short-term effects for calf development and potential longer-term implications for behavior and welfare. Welfare of commercially raised calves may be improved by refining social housing to better accommodate natural social behavior.

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.

Taste agents as modulators of the feeding behaviour of grazing yaks in alpine meadows

Feeding behaviour plays a significant role in promoting good animal health and welfare. It is also reflective of the quality and quantity of available feed. In fact, grazing livestock do not select their feed randomly, rather their behaviour is influenced by the texture, taste, and smell of each pasture species. Although taste agents are often used to modify feed intake for captive livestock, the effect on the feeding behaviour of grazing livestock has not yet been extensively evaluated in native grasslands. To address this gap in knowledge, herein, we sprayed three types of taste agents-salty (SA), sweet (SW), and bitter (BT)-on alpine meadows to investigate their effect on the grazing behaviour of yaks (Bos Grunniens) on the Qinghai-Tibetan Plateau (QTP). Behavioural observations showed that grazing was concentrated primarily in the morning and afternoon, while ruminating/resting peaked at noon; however, the diurnal behavioural patterns of grazing yaks were not affected by the taste agents. Application of the SA agent significantly increased the yaks' grazing time, bites per minute, bites per step, time per feeding station, and steps per feeding station, while significantly reducing walking time, steps per minute, and number of feeding stations per minute. Meanwhile, application of the SW agent significantly increased the yaks' time per feeding station, however, significantly reduced the steps per minute and number of feeding stations per minute. In contrast, the BT agent significantly increased the yaks' walking time, steps per minute, and number of feeding stations per minute, while significantly reducing grazing time, bites per minute, bites per step, and time per feeding station. Application of the SA agent also significantly increased the intake of favoured, edible, and inedible forage, while the SW agent improved inedible forage intake, however, had a more subtle effect on favoured and edible forage intake. Meanwhile, the BT agent had an inhibitory effect on grazing intake. Hence, the structural equation model suggested that taste agents may directly or indirectly influence grazing behaviour by regulating feeding behaviour. Our findings provide a theoretical basis for using taste agents in grasslands to control the grazing behaviour of livestock and provide a method to promote the stability of grassland communities, while mitigating the degradation of grasslands in the QTP.

The influence of personality and weaning method on early feeding behavior and growth of Norwegian Red calves

Some research has described a relationship between personality and feeding behavior at weaning in Holstein dairy calves; our objective was to determine if personality traits, especially sociability, are associated with differences in feeding behavior and growth in Norwegian Red calves. Our secondary objective was to assess the interaction between personality traits and gradual weaning method (by age or by concentrate intake) on the behavior and growth of calves. Twenty-seven Norwegian Red calves were housed in 7 groups of 3 to 5 calves, with group composition based on birthdate to ensure that there were no more than 21 d between the youngest and oldest calves. Calves had access to an automated milk and concentrate feeder with ad libitum access to concentrates, water, hay, and silage. Calves were semi-randomly assigned to be either gradually weaned by age at d 56, or weaned by intake, where weaning was initiated based on reaching specific concentrate intake targets. We measured milk intake, concentrate intake, and the number of unrewarded visits to the automated feeder during each of 5 experimental periods: preweaning (12 L/d; 10-30 d of age), weaning (milk allowance gradually reduced by method until completely weaned), weaning week (3 d before weaning and the first 7 d of 0 L/d milk allowance), postweaning (20 d after complete milk removal), and the total experimental period (10-20 d postweaning). At 21 and 80 d of age, individual behavioral responses toward novelty and isolation (indicative of personality) were recorded in 3 personality tests: novel environment, novel object, and a social motivation test (time taken to return the group). At 83 d of age, a group novel object test was conducted. Principal component analysis revealed 3 factors interpreted as personality traits (playful/exploratory, vocal/active, interactive in group test) that together explained 56% of the variance. Calves that were more playful/exploratory consumed more milk per day preweaning and more concentrate per day over the experimental period. Calves that were more vocal/active (interpreted as a type of sociability trait where vocalizations and pacing serve to communicate with conspecifics when isolated from herd) had lower preweaning milk intakes and lower concentrate intakes over the experimental period. Calves that were more interactive in the group test (interpreted as a type of sociability trait when with other herd mates) had lower preweaning and weaning concentrate intakes. There was no interaction between personality traits and weaning method on feeding behavior or performance outcomes; however, calves that were weaned by intake (successfully reached all concentrate targets) had higher average daily gains postweaning, likely due to consuming more concentrate per day over the entire experiment, than calves who failed to reach all targets, or were weaned by age. We concluded that the sociability traits of Norwegian Red calves were related to individual differences in milk and concentrate intake. Although the relationship between personality and feeding behavior and growth did not depend on weaning method, gradual weaning based on individual concentrate intakes provides an opportunity for calves to wean at a pace that fits the needs of each individual calf.

Understanding Behavioural Development of Calves in Natural Settings to Inform Calf Management

Simple Summary

Animal welfare research is intended to address societal concerns regarding animal care, including natural living concerns. We reviewed the literature on calf behaviour when reared in more naturalistic outdoor systems with their mothers and herd. Understanding calf behaviour in more natural settings may help inform changes in calf management and housing that promote behaviours important to calf welfare.

Abstract

One important type of animal welfare concern is “natural living” (i.e., that animals are able to express natural behaviours that are important to them, and to engage with aspects of the natural world that they find important). The aims of this narrative review were to describe the behavioural development of calves (Bos taurus) in natural settings and use this to identify characteristics of natural systems that may be important to consider relative to this natural living conception of animal welfare. At birth, calves are licked by their mothers and soon stand to suckle for colostrum, and during the milk-feeding period, calves spend much of their time lying down. In natural systems, calves perform a variety of social behaviours with herd-mates, and slowly transition from their mother’s milk to eating solid food, by gradually increasing time spent grazing and ruminating. In contrast, on most commercial dairy systems, dairy calves are removed from their mothers at birth, housed individually, fed restricted amounts of milk and weaned abruptly at a young age. The results of this review suggest that accommodating key natural behaviours, for example through the use of teat feeding of milk, social housing, and gradual weaning, can help address welfare concerns.

Early-Life Dam-Calf Contact and Grazing Experience Influence Post-Weaning Behavior and Herbage Selection of Dairy Calves in the Short Term

Rearing dairy calves with their mothers could teach them how to graze, optimizing grass use, and improving their welfare and performance. We tested the short-term effects of dam-calf contact experience on grazing and social behavior of weaned calves, monitored over seven days for their first post-weaning grazing experience. “Dam” (D) calves were reared and grazed with their mothers until weaning. “Mixed” calves (M) were separated from their mothers after 4 ± 0.5 weeks, they experienced dam-calf contact, but not grazing. “Standard” (S) calves had never experienced either dam-calf contact (separated at birth) or grazing. Each group grazed an equivalent pasture plot offering heterogeneous herbage. Scan sampling of calves' activities was performed every 5 min, 6 h per day, on Days 0, 1, 2, 3, and 7. Daily, the time when calves started grazing after introduction to pasture, and the number and duration of their grazing cycles were measured. Daily activities were differentiated into ingestion, rumination, and idling. The proportion of time that calves spent grouped with other individuals or isolated, and standing or lying were recorded. When grazing, their bites were characterized by botanical family group, height of the selected bite and vegetation status. Individual average daily gains from the 2-week periods before and after grazing were calculated, and were equivalent between groups (313 ± 71 g/d). On Day 0, D-calves started grazing immediately (1 ± 4.1 min), unlike M- and S-calves (39 ± 4.1 and 23 ± 4.1 min), and D-calves grazed patches of dry grass 21.7 times less than M-calves and 16.9 times less than S-calves. Dry herbage patch preference and grazing start time differences disappeared on Day 1. Calves spent the same time ingesting and idling, but M-calves spent on average 1.6 times less ruminating than D- or S-calves. The D-calves showed grazing behavior similar to that of adult cows, selecting grasses throughout pasture utilization, although legumes and forbs were present in the grazed layer. On the contrary, M- and S-calves did not express any specific preference. The S-calves spent more time isolated but had more positive reciprocal interactions than the calves in the other groups.

The Influence of Different Types of Outdoor Access on Dairy Cattle Behavior

Pasture access for dairy cows is highly valued both by cows and the public at large. When pasture access is not feasible, farmers can provide cows with alternative forms of outdoor access, such as an outdoor bedded pack, that may be easier to implement on some farms. We reviewed the literature on how lying, standing, walking, feeding, social, and estrus behaviors are influenced by pasture and other types of outdoor areas. Pasture allows the expression of grazing and can facilitate the expression of lying, standing, walking, and estrus behaviors. In addition, pasture can decrease the number of negative social interactions between cows, likely because more space per cow is provided than what is normally available indoors. The provision of soft flooring and an open space in outdoor bedded packs appears to provide some benefits for lying, standing, and walking behavior and may also have positive effects on social behavior, especially with larger space allowances. The effects of an outdoor bedded pack on estrus behavior are less well-documented, but the provision of a standing surface that provides better footing than typically available indoors may promote estrus behavior. Alternative outdoor areas assessed to date appear to be less attractive for cows than pasture, perhaps because these areas do not provide the opportunity to graze. We encourage future research to investigate the importance of grazing for dairy cows. The motivation of dairy cows to access alternative outdoor areas should also be investigated. As cow preference for the outdoors depends on many factors, providing cows a choice may be of particular importance.