Some like it varied: individual differences in preference for feed variety in dairy heifers

Motivation to explore is believed to be widespread among animals, but exploratory behaviour varies within populations. Offering variety in feed is one simple way of allowing intensively housed dairy cattle to express exploratory foraging behaviour. Individuals’ exploration of different feed types, as with other new stimuli, likely reflects a balance between exploratory motivation and fear of novelty. We tested the degree to which Holstein heifers (n=10) preferred variety in feed vs. a constant, high quality mixed ration, by first providing varying types of forages and then varying flavours of mixed feed. We also investigated individual differences in exploratory behaviour by measuring switching between feed bins. Individual consistency in preferences was assessed between tests, and longer-term consistency was evaluated by comparing these results with behaviour in novel object and novel feed tests before weaning. On average, the heifers preferred the constant, familiar feed (spending on average just 20% of their time at varied feed bins), but this preference varied among individuals (from 0 to 46% of time eating in the forage trial, and 0 to 93% in the flavour trial). Preference for varied forages correlated positively with intake of novel feed as calves (rs=0.72, n=9). Preference for varied flavours showed a negative correlation with latency to approach a novel object (rs=-0.65). It thus appears that preference for variety and exploratory foraging behaviour reflect consistent personality traits. These results suggest that offering novel feeds on a rotating schedule as a supplement to the regular diet may be an effective form of enrichment for at least some individuals within a herd

Effect of pen size, group size, and stocking density on activity in freestall-housed dairy cows

The purpose was to determine the effects of the physical dimensions of the pen and group size and stocking density on cow activity. Cows (randomly assigned to 4 groups of 6 animals each) were tested in pens with 24 or 12 lying places and in groups with 12 or 6 cows. All groups were tested in each of the 4 treatments with treatment order allocated using a 4 × 4 Latin square. The distance moved and the number of movements were calculated using 5-min scan sampling of video recordings over a 48-h period. Time spent lying down, number of lying bouts, and the duration of each lying bout were recorded using activity sensors. Displacements at the feed bunk were assessed by continuous analysis of video for 3 h after the delivery of the fresh feed in the afternoon. Cows moved greater distances when kept in a large versus small pens (330.2 vs. 270.1 ± 11.6 m/d; mean ± SE), irrespective of group size. Cows moved more often when kept in the larger pen (21.3 vs. 19.2 ± 0.63% of scans). The time spent lying down decreased when density increased (59.1 vs. 55.8 ± 2.3% of scans at 25% and 100% stocking, respectively). Treatment had no effect on the number of displacements at the feed bunk. Physical dimensions of the pen play an important role in how much cows move, and stocking density affects lying time.The purpose was to determine the effects of the physical dimensions of the pen and group size and stocking density on cow activity. Cows (randomly assigned to 4 groups of 6 animals each) were tested in pens with 24 or 12 lying places and in groups with 12 or 6 cows. All groups were tested in each of the 4 treatments with treatment order allocated using a 4 × 4 Latin square. The distance moved and the number of movements were calculated using 5-min scan sampling of video recordings over a 48-h period. Time spent lying down, number of lying bouts, and the duration of each lying bout were recorded using activity sensors. Displacements at the feed bunk were assessed by continuous analysis of video for 3 h after the delivery of the fresh feed in the afternoon. Cows moved greater distances when kept in a large versus small pens (330.2 vs. 270.1 ± 11.6 m/d; mean ± SE), irrespective of group size. Cows moved more often when kept in the larger pen (21.3 vs. 19.2 ± 0.63% of scans). The time spent lying down decreased when density increased (59.1 vs. 55.8 ± 2.3% of scans at 25% and 100% stocking, respectively). Treatment had no effect on the number of displacements at the feed bunk. Physical dimensions of the pen play an important role in how much cows move, and stocking density affects lying time

Inconsistency in dairy calves’ responses to tests of fearfulness

Fear is an important welfare problem for farm animals, including cattle. A variety of methods of assessing fear have been proposed, but the reliability and validity of these methods, and ways of improving these characteristics, have received little study. We conducted a series of experiments to assess the consistency of dairy calves’ responses of novel objects and to humans, and to investigate factors that might improve reliability. In the first experiment, latency to touch a novel object had moderate reliability (rs = 0.54), and latency to touch a stationary, familiar human had negligible reliability (rs = 0.26). Experiment 2a used the same test protocols, but with a shorter interval between repeat testing and using different stimuli in the two novel object tests; this change did not improve reliability (e.g. rs = 0.29 for the novel-object test). Reliability for this test was improved (rs = 0.58) in Experiment 2b, when the same object was used in both tests rather than a truly novel object being used the second time. Experiment 2a found ceiling effects in the response to human test associated with the short period during which approach responses were recorded. High reliability was found in Experiment 2b, where the maximum test duration was doubled, but this effect not due to the extended duration. Experiment 3 assessed reliability of a response to human approach at the farm rather than individual level, in this case assessing responses to an unfamiliar person. The proportion of calves making contact with the person was not reliable (rs = 0.22), but the proportion retreating from the person had moderate reliability (rs = 0.52). Reliability was improved by excluding data from calves that had coughs on the day of testing. Conducting multiple tests per individual using different stimuli and reporting health status of the animals are recommended for future research and animal welfare assessment schemes that include measures of fear

Benchmarking cow comfort on North American freestall dairies: Lameness, leg injuries, lying time, facility design, and management for high-producing Holstein dairy cows

In this paper, we describe a novel approach to corporate involvement in on-farm assessment, driven by the desire to provide a service for dairy producers and to create a vehicle for engagement on issues of dairy cow welfare. This program provides producers with feedback on animal-based (including gait score, leg injuries, and lying time) and facility-based (including freestall design, bedding practices, feed bunk design and management, and stocking density) measures that can be used to better address their management goals. The aim of this paper is to describe variation in the prevalence of lameness and leg injuries, lying behavior, facility design, and management practices for high-producing cows on freestall dairy farms in 3 regions of North America: British Columbia (BC; n = 42); California (CA; n = 39); and the northeastern United States (NE-US; n = 40). Prevalence of clinical lameness averaged (mean ± SD) 27.9 ± 14.1% in BC, 30.8 ± 15.5% in CA, and 54.8 ± 16.7% in NE-US; prevalence of severe lameness averaged 7.1 ± 5.4% in BC, 3.6 ± 4.2% in CA, and 8.2 ± 5.6% in NE-US. Overall prevalence of hock injuries was 42.3 ± 26.2% in BC, 56.2 ± 21.6% in CA, and 81.2 ± 22.5% in NE-US; prevalence of severe injuries was 3.7 ± 5.2% in BC, 1.8 ± 3.1% in CA, 5.4 ± 5.9% in NE-US. Prevalence of swollen knees was minimal in CA (0.3 ± 0.6%) but high (23.1 ± 16.3%) in NE-US (not scored in BC). Lying times were similar across regions (11.0 ± 0.7 h/d in BC, 10.4 ± 0.8 h/d in CA, 10.6 ± 0.9 h/d in NE-US), but individual lying times among cows assessed varied (4.2 to 19.5 h/d, 3.7 to 17.5 h/d, and 2.8 to 20.5 h/d in BC, CA, and NE-US, respectively). These results showed considerable variation in lameness and leg injury prevalence as well as facility design and management among freestall farms in North America. Each of the 3 regions had farms with a very low prevalence of lameness and injuries, suggesting great opportunities for improvement on other farms within the region

A systematic review of the effects of prolonged cow-calf contact on behavior, welfare, and productivity

Separation of calves from cows within hours or days of birth is common on dairy farms. Stakeholders have conflicting perspectives on whether this is harmful or beneficial for the animals’ welfare and production. Our objective was to critically evaluate the scientific evidence for both acute and long-term effects of early separation versus an extended period of cow-calf contact. The outcomes investigated were the behavior, welfare (excluding physical health) and performance (milk yield and growth, respectively) of dairy cows and calves. Primary research papers were found through targeted Web of Science searches, the reference lists of recent reviews for each topic, and the reference lists of papers identified from these sources. Studies were included if they were published in English, the full text was accessible, and they compared treatments with and without contact between dairy cows and calves for a specified period. Early separation (within 24 h post-partum) was found to reduce acute distress responses of cows and calves. However, longer cow-calf contact typically had positive longer-term effects on calves, promoting more normal social behavior, reducing abnormal behavior and sometimes reducing responses to stressors. In terms of productivity, allowing cows to nurse calves generally decreased the volume of milk available for sale during the nursing period, but there was no consistent evidence of reduced milk production over a longer period. Allowing a prolonged period of nursing increased calf weight gains during the milk-feeding period. In summary, extended cow-calf contact aggravates the acute distress responses and reduces the amount of saleable milk while the calves are suckling, but can have positive effects on behaviors relevant to welfare in the longer term and benefit calf growth. The strength of these conclusions is limited, however, given that relatively few studies address most of these effects and that experimental design including timing of contact and observations are often inconsistent across studies. Few studies presented indicators of long-term welfare effects other than abnormal and social behavior of the calves

Review: Using animal welfare to frame discussion on dairy farm technology

The use of technology on dairy farms has increased dramatically over the last half-century. The ways that scientists describe the potential benefits and risk of technology are likely to affect if it is accepted for use on farms. The aim of our study was to identify papers that describe a linkage between technologies used on dairy farms and the welfare of dairy cattle. Our systematic review identified 380 papers, of which 28 met our inclusion criteria and were used to describe the technologies examined, the welfare-relevant measures used, and the ways in which authors framed welfare benefits and risks associated with the technologies. The large majority (27 of 28 papers) used positive frames, considering how the technology could improve welfare. Some authors carefully articulated the logic linking the specific measures to specific welfare-related outcomes (such as the use of accelerometer data to draw inferences about changes in lying times), but others made more general inferences (about health and welfare) that were not (and perhaps could not) be assessed. We conclude that much of the framing focused on animal welfare is biased toward welfare benefits and that future work should strive to address both potential benefits and harms; more balanced coverage may better inform solutions to the problems encountered by the people and animals affected by the technology. Welfare is a complex and multifaced concept, and it is unlikely that any one technology (or perhaps even a combination of technologies) can adequately capture this complexity. Thus, we encourage authors to restrict their claims to specific, welfare-relevant measures that can be assessed independently and thus validated. More general claims about welfare should be treated with skepticism

Water and the Welfare of Farm Animals

Provision of adequate water supplies is essential for the welfare of farmanimals. Water forms the largest component of an animal's body and is an essentialnutrient required for all biological functions, including temperature regulation, digestion, foetal development, and production. This essential nutrient can only be restricted for short periods of time. Water deprivation results in substantial welfare concerns, as it can hinder biological functioning, and has been associated withmorbidity and, in cases of extreme deprivation, mortality. It is likely associatedwith a highly negative emotional state in farm animals (e.g. in humans referred to asthirst). Both quality and quantity of water may limit water intake, and management factors such as high stocking density at the water source can also negatively affect water intake. Providing examples from the primary production species, cattle, pigs, and poultry, we describe the importance of water quality and quantity in foodanimal production

Short communication: dominance in free-stall-housed dairy cattle is dependent upon resource

The main objective was to assess the consistency in competitive success across 3 common resources available to dairy cows housed in free-stall barns. Specifically, we determined if those cows that displaced other cows most often at the feed bunk (high-ranking) had priority of access to free-stalls or a mechanical brush. Our secondary objective was to determine if the displacements at each resource were a function of usage of that resource. These objectives were tested using 6 groups of 12 lactating dairy cows housed in pens with 0.6 m of bunk space per cow, 1 free-stall per cow, and 1 mechanical brush per pen. Time-lapse video was used to quantify the time spent feeding, in the stalls, and using the mechanical brush. The incidence of displacements at the feed alley and lying area was measured for 3 d consecutively. Usage was lower for the brush, so displacements were monitored for 14 d consecutively. The individual measures of competitive success were not highly correlated between resources indicating a cow that frequently displaced other cows for access to one particular resource did not always do so when accessing the other resources. Competition at the feeder was responsible for 87.6 +/- 1.4% of displacements observed throughout the experiment, indicating that gaining access to feed was a high priority for cows. These results suggest that competitive success by dairy cows may vary according to each cow's motivation to access the resource

Regrouping induces anhedonia-like responses in dairy heifers

Intensively housed dairy cattle are commonly regrouped (mixed into a new social group) as part of routine farm procedures. This stressful procedure triggers heightened levels of agonistic behaviors and disrupts animals' time budgets. However, little is known regarding the effects of regrouping on cattle's affective states. The aim of this study was to explore whether regrouping (involving a change in both the social and physical environment) triggers anhedonia (i.e., the reduced ability to experience pleasure) in 6-mo-old dairy heifers, a phenomenon associated with negative mood. In this study, we assessed anhedonia using changes in the use of a mechanical brush. Holstein heifers (n = 16) were trained to use a mechanical brush and then given the opportunity to individually brush for 10 min every 2 d. Time spent brushing (during a 10-min brush test) was collected before, during, and after regrouping (2-d interval) with the assumption that heifers would reduce their use of the brush during regrouping. Each heifer was individually regrouped into a new social group composed of 12 older and unfamiliar heifers and allowed access to the brush at 8 and 56 h after the onset of regrouping. Immediately after the last test, each heifer was brought back to her original pen and allowed to mingle with familiar pen-mates before being tested again 2 and 4 d later. When tested 8 h after regrouping, heifers reduced time spent brushing by 44 ± 27% (95% confidence interval: −96.18 to −41.8) compared with before regrouping; however, no differences were detected 56 h after regrouping. There was no relationship between the intensity of the decrease in brush use and any behaviors (number of agonistic interactions received, time heifers spent resting, or synchronization at the feed bunk) recorded for the 8 h immediately before testing (i.e., between 0 and 8 h and between 48 and 56 h after regrouping). These results indicate that regrouping induces anhedonia-like responses in dairy heifers on the day of regrouping. This routine procedure may thus induce negative mood in dairy heifers. This response was not related to behaviors typically collected to assess the negative effects of regrouping. Maintaining dairy cattle in stable social groups should be favored