Effects of 2 wintering practices on behavioral and physiological indicators of welfare of nonlactating, pregnant dairy cattle in a pasture-based system.

In countries with pasture-based dairy systems and relatively cold winters, such as New Zealand, it is common to manage pregnant, nonlactating cows on forage crop paddocks rather than pasture, due to slow pasture growth rates. Wintering dairy cattle on grazed crops can compromise welfare if wet and muddy underfoot conditions occur, which can reduce lying. This study investigated behavioral and physiological indicators of welfare of cows under 2 wintering practices: cows managed on and grazed kale crop (Brassica oleracea), and cows managed on pasture with baled hay. Following dry-off (d 0), 80 cows were randomly assigned to 1 of the 2 wintering practices (40 cows/practice) and monitored between d 4 and 32 (phase 1). During this period, lying and stepping behavior was continuously recorded using leg-based accelerometers. Blood samples were obtained at d 0 and 32 for measurements of thyroxine (T4), nonesterified fatty acids (NEFA), white blood cells (WBC), and red blood cells. All data for phase 1 were presented descriptively due to the lack of treatment replication. Daily mean air temperature during this period was 5.2°C (range: 0.0-10.7°C), and rainfall was 1.1 mm/d (range: 0-5.6mm/d). Between d 4 and 32, cows in both groups spent similar amounts of time lying (pasture with hay cows: 8.9 h/24 h ± 2.57, kale crop cows: 8.7 h/24 h ± 3.06, mean ± SEM). Both groups reduced their lying on wet and cold days, and there was evidence of rebound lying once unfavorable weather conditions stopped. Cows on kale crop had numerically higher NEFA and lower WBC compared with cows managed on pasture, although most physiological values were within normal ranges. In a second phase of the study (d 34 and 35), cows were managed under controlled, replicated conditions in the 2 wintering practices using typical on-farm stocking rates (2 or 4 cows per group in the pasture with hay and kale crop treatments, respectively; n = 10 groups/treatment). During this period, cow behavior, skin and surface temperatures, hygiene scores, feed intakes, and ground conditions were measured. Weather conditions during the 48-h exposure were mostly cold and dry (mean air temperature: 7.8°C, range: -2.2 to 20.5°C). Cows managed on pasture with hay spent more time lying down on the first day of exposure; however, this was likely due to less space being available to kale cows on this day. Cows managed on pasture with hay ruminated more than cows on kale crop on both days of observations (d 1: 37.9% vs. 30.9% of observations, d 2: 36.8% vs. 28.7% of observations for pasture with hay and kale crop groups, respectively) and were lying more often in postures indicative of greater thermal comfort. Cows managed on pasture with hay had higher skin and surface temperatures compared with cows on kale crop, whereas cows on kale crop had dirtier coats. Results suggest that opportunities for thermal comfort were greater for cows managed on pasture with hay bales, which may be due to increased rumination activities and more insulated lying areas.

Effects of provision of drinking water on the behavior and growth rate of group-housed calves with different milk allowances.

Despite the clear importance of drinking water, calves are not always provided water on farm for the first few weeks of life. The main objective of this study was to investigate the effects of water provision (access or no access) and milk allowance (high or low) on the behavior and growth rate of calves. Fifty mixed-breed calves were each assigned to 1 of 4 treatments: (1) water and high (10 L/d) milk allowance (n = 13), (2) no water and high milk allowance (n = 12), (3) water and low (5 L/d) milk allowance (n = 12), or (4) no water and low milk allowance (n = 13). Visits to the water trough, water intake, milk drinking behavior (visits and drinking speed), proportion of observations eating hay and calf starter, and lying behavior were recorded from when the calves were, on average, 5 d of age (standard deviation: 2 d) for 4 consecutive weeks. Calves were weighed weekly. Some calves began to visit the water trough from the start of the recording period, as early as 4 d of age, and water intake increased with age for all calves that had access to it. This increase was greater for calves provided a high milk allowance. Water intake increased with ambient temperature, which highlights the importance of providing drinking water in warm conditions. Overall, calves spent a greater proportion of observations eating hay and calf starter with age. The provision of drinking water was associated with a greater proportion of observations eating hay but less eating calf starter. The increase in the proportion of observations eating calf starter with age was greater for calves on a low milk allowance than of those provided a high milk allowance; this is likely due to calves on a low milk allowance searching for nutrients and energy. Calves on a high milk allowance grew faster and spent more time lying compared with calves with a low milk allowance, thus suggesting greater satiety of well-fed calves. Our results suggest that calves should have free access to drinking water from birth and that access to drinking water may aid in hay (fiber) intake and possibly rumen development.

Effects of 3 surface types on dairy cattle behavior, preference, and hygiene.

Muddy surfaces have negative effects on the health and welfare of dairy cattle, and if possible, cows will avoid this surface. However, it is unclear whether it is the moisture content or the contamination with manure that is aversive to the cows. This study aimed to assess the use and preference for different wood chip (0.4 m deep) surface types: (1) clean and dry (clean, dry matter content, DM: 44 ± 2.8%), (2) dirty (dirty, contaminated with manure, DM: 40 ± 3.7%), and (3) clean and wet (wet, wetted by water, DM: 23 ± 3.3%). Eighteen nonlactating, pregnant cows were tested individually (mean 24-h temperature: 9.9 ± 4.46°C, mean ± standard deviation for all preceding values). Cows were kept indoors in test pens for 18 h on wood chip without feed and 6 h on pasture to allow for daily feed intake. To ensure cows made informed choices and to measure changes in behavior and hygiene associated with each option, they were first exposed to each surface for 5 d (n = 12 cows per surface type when they were restricted on one surface; i.e., each cow was exposed to 2 treatment surfaces only). Cows on the wet surface spent the least amount of time lying when restricted to one surface for 18 h (wet: 21%, dirty: 57%, clean: 64%) and spent more time lying when on pasture for 6 h (wet: 13%, dirty: 4%, clean: 3%). The total lying times during the 5-d surface exposure were wet: 4.6 ± 1.04 h, dirty: 10.6 ± 0.25 h, and clean: 11.7 ± 0.25 h per 24 h. Cows restricted on the wet surface for 18 h had fewer bouts (no.) of lateral lying (wet: 0.9 ± 1.36, dirty: 6.3 ± 1.36, clean: 8.4 ± 1.38), spent less time lying with their heads supported (wet: 18.9 ± 7.17 min, dirty: 36.7 ± 7.17 min, clean: 39.1 ± 7.26 min), and spent less time with the front legs tucked (wet: 16 ± 4.3%, dirty: 41 ± 4.3%, clean: 50 ± 4.3% of time spent lying, mean ± standard error of the mean for all preceding values), than cows on the other surfaces. Cows on the dirty surface were less clean compared with the other treatment groups (0.6 of a score on a 5-point scale; standard error of the differences of means: 0.11 for both comparisons). They were then given a free choice between 2 known surfaces for 2 consecutive days (n = 6 per pairwise choice). Cows ranked the surfaces as clean > dirty > wet. In summary, there is compelling evidence that wet surfaces impair the welfare of dairy cattle by affecting the quantity and quality of rest. Rebound responses indicate that the motivation to rest is not fulfilled on wet surfaces. Finally, when given a choice, they show clearly that they will avoid wet and dirty surfaces. The combined results indicate that changes in affective state likely underlie these behavioral responses.

Different animal welfare orientations towards some key research areas of current relevance to pastoral dairy farming in New Zealand.

The New Zealand dairy industry needs to meet public expectations regarding animal welfare in order to retain the freedom to operate and achieve market success. Three key orientations towards animal welfare assessment have been identified, namely biological functioning, affective state and natural living, the last two of which are more recent foci for societal concern. Biological functioning was the first and most-studied aspect of animal welfare and continues to be important, but now the contribution of affective state to animal well-being is emphasised much more. Natural living, or naturalness, has received relatively less attention from animal welfare science. It is proposed that increasing the use of naturalness as a contextual reference point for considering species-specific behavioural expressions of affective state will enhance its inclusion in animal welfare assessment. Nevertheless, all three orientations need to be considered in order to evaluate the significance of welfare research findings. On this basis, five key aspects of the New Zealand dairy industry that have been the subject of recent research, due to the risk of them not meeting public expectations, are highlighted and discussed. The aspects are provision of shade and shelter, meeting targets for body condition, provision of comfortable surfaces for rearing calves, and for adult cows while off pasture, and pain relief for disbudding of calves. Research evidence indicates that the industry guidelines on body condition score, if met, would satisfy public expectations across the three orientations to animal welfare, whereas further work is needed on the other aspects. It is concluded that considering these three orientations to animal welfare when planning research and then evaluating the outcomes will help to promote the market success of the dairy industry in New Zealand.

A field study of the behavioral and physiological effects of varying amounts of shade for lactating cows at pasture.

Shade reduces the negative effects of heat load, but little is known about how much is required for efficient cooling in commercial settings. The effect of the amount of shade on 8 Holstein-Friesian herds was studied for 2 consecutive summers (mean temperature: 23 °C) on 6 commercial, pasture-based dairy farms. Farms varied in the amount of natural shade provided (range: 0 to 15.6m(2) shade/cow). Time spent in shade, near water, eating, ruminating, lying, and standing were recorded between 1000 and 1530 h in 31 shaded and 11 unshaded paddocks using 20-min instantaneous scan observations of 15 focal cows/herd. Respiration rate and panting score (0 to 4.5) was recorded for focal animals once per hour. The total numbers of cows in shade, near water, and with panting scores ≥ 2 were recorded every 30 min. Cows without shade spent 4% more time lying than cows with shade (standard error of the difference, SED = 1.9%). A larger proportion of the herd had panting scores ≥ 2 when no shade was available (6 vs. 2% of the herd, SED = 1.2%), and respiration rates were higher by 8 breaths/min in cows without shade (SED = 4.7 breaths/min). Under the conditions tested, the maximum proportion of the herd that was observed using the shade increased by 3.1% for every 1-m(2) increase in shade size [standard error (SE) = 1.51%], and all cows were first seen simultaneously using shade when 2m(2)/cow was provided. For every 1-m(2) increase in shade, 0.3% fewer cows had panting score ≥ 2 (SE = 0.12%). We observed no significant relationships between the amount of shade available and any other variables. Although additional work is required to make specific recommendations, these results indicate that providing more shade allowed a higher proportion of animals to use this resource and reduced respiratory signs of heat load.

Effects of short-term repeated exposure to different flooring surfaces on the behavior and physiology of dairy cattle.

Dairy cattle managed in some pasture-based systems such as in New Zealand are predominantly kept outdoors all year around, but are often taken off pasture for periods of time in wet weather to avoid soil damage. It is common to keep cattle on concrete surfaces during such "stand-off" practices and we investigated whether the addition of rubber matting onto concrete areas improves the welfare of dairy cattle. Sixteen groups of 5 cows (4 groups/treatment, 5 cows/group) were allocated to 1 of 4 treatments (concrete, 12-mm-thick rubber mat, 24-mm-thick rubber mat, or deep-bedded wood chips) and kept on these surfaces for 18 h/24h for 4 consecutive days (6h on pasture/24h). Each 4-d stand-off period was repeated 4 times (with 7 d of recovery between periods) to study the accumulated effects of repeated stand-off. Lying behavior was recorded continuously during the experiment. Gait score, stride length, hygiene score, live weight, and blood samples for cortisol analysis were recorded immediately before and after each stand-off period. Cows on wood chips spent the most time lying, and cows on concrete spent the least time lying compared with those on other surfaces [wood chips: 10.8h, 24-mm rubber mat: 7.3h, 12-mm rubber mat: 6.0 h, and concrete: 2.8h/18 h, standard error of the difference (SED): 0.71 h]. Cows on concrete spent more time lying during the 6h on pasture, likely compensating for the reduced lying during the stand-off period. Similarly, cows on concrete spent more time lying on pasture between stand-off periods (concrete: 12.1h, 12-mm rubber mat: 11.1h, 24-mm rubber mat: 11.2h, and wood chips: 10.7h/24h, SED: 0.28 h). Cows on concrete had higher gait score and shorter stride length after the 4-d stand-off period compared with cows on the other surface types, suggesting a change in gait pattern caused by discomfort. Cows on rubber mats were almost 3 times dirtier than cows on concrete or wood chips. Cortisol and live weight decreased for all treatment groups during the stand-off period. We observed no major effect of the repeated stand-off exposure. In summary, adding rubber matting onto concrete surfaces for stand-off purposes is beneficial for animal welfare. A well-managed wood chip surface offered the best welfare for dairy cows removed from pasture, and the findings of this study confirm that a concrete surface decreases the welfare of cows removed from pasture.

Calving body condition score affects indicators of health in grazing dairy cows.

The objectives of this study were to determine the effect of calving body condition score (BCS) on cow health during the transition period in a pasture-based dairying system. Feed inputs were managed during the second half of the previous lactation so that BCS differed at drying off (BCS 5.0, 4.0, and 3.0 for high, medium, and low treatments, respectively: a 10-point scale); feed allowance was managed after cows were dried off, such that the BCS differences established during lactation remained at the subsequent calving (BCS 5.5, 4.5, and 3.5; n=20, 18, and 19, for high, medium, and low treatments, respectively). After calving, cows were allocated pasture and pasture silage to ensure grazing residuals >1,600 kg of DM/ha. Milk production was measured weekly; blood was sampled regularly pre- and postpartum to measure indicators of health, and udder and uterine health were evaluated during the 6 wk after calving. Milk weight, fat, protein, and lactose yields, and fat content increased with calving BCS during the first 6 wk of lactation. The effect of calving BCS on the metabolic profile was nonlinear. Before calving, cows in the low group had lower mean plasma ß-hydroxybutyrate and serum Mg concentrations and greater mean serum urea than cows in the medium and high BCS groups, which did not differ from each other. During the 6 wk after calving, cows in the low group had lower serum albumin and fructosamine concentrations than cows in the other 2 treatment groups, whereas cows in the low- and medium-BCS groups had proportionately more polymorphonucleated cells in their uterine secretions at 3 and 5 wk postpartum than high-BCS cows. In comparison, plasma ß-hydroxybutyrate and nonesterified fatty acid concentrations increased linearly in early lactation with calving BCS, consistent with a greater negative energy balance in these cows. Many of the parameters measured did not vary with BCS. The results highlight that calving BCS and, therefore, BCS through early lactation are not effective indicators of functional welfare, with the analyses presented indicating that both low and high BCS at calving will increase the risk of disease: cows in the low group were more prone to reproductive compromise and fatter cows had an increased risk of metabolic diseases. These results are important in defining the welfare consequences of cow BCS.

Behavioral and physiological effects of a short-term feed restriction in lactating dairy cattle with different body condition scores at calving.

Body condition score (BCS) around calving, and the typical BCS loss for up to 100 d after parturition, is associated with both production and reproductive performance of dairy cattle. In addition, there is public concern that thin cows may have impaired welfare, particularly in early lactation where feed demand exceeds pasture growth, and a lag exists between peak milk energy requirements and intake. The aim of this experiment was to determine how BCS at calving influences behavioral and physiological responses to a short-term feed restriction at 47 DIM. Body condition score (on a 10-point scale) at calving was manipulated by modifying the diets in the previous lactation of healthy dairy cattle to generate 3 treatment groups: low BCS (3.4; n=17), medium BCS (4.6; n=18), or high BCS (5.4; n=20). Cows were tested in 4 groups for 8 consecutive days; testing consisted of different levels of feed allocation (d 1 and 2: 100%; d 3 and 4: 75%; d 5: 50%; d 6 to 8: 125%), where 100% was 15kg of DM/cow per day. All BCS groups had similar and marked behavioral and physiological responses to feed restriction. For example, they increased vocalization, time spent eating silage and grazing, aggressive behavior, and fat metabolism (as measured by concentrations of ß-hydroxybutyrate and nonesterified fatty acids), and reduced milk production. Body condition affected some of these responses. Fewer cows with low BCS engaged in aggressive interactions in a feed competition test (trough filled with silage that could be consumed in 15 min) on the first day of feed restriction (low: 32%; medium: 74%; high: 64%; standard error of difference=15.4%). High BCS cows had greater concentrations of ß-hydroxybutyrate and nonesterified fatty acids throughout the experimental period, which suggests more fat mobilization; however, plasma leptin and fecal glucocorticosteroid metabolite concentrations were unaffected by BCS. Whereas cows demonstrated marked responses to feed restriction, the results suggest that a BCS of 3.4, 4.6, or 5.4 in healthy cows at calving does not overwhelmingly influence this response at 47 DIM.

Effect of previous handling experiences on responses of dairy calves to routine husbandry procedures.

The nature of human-animal interactions is an important factor contributing to animal welfare and productivity. Reducing stress during routine husbandry procedures is likely to improve animal welfare. We examined how the type of early handling of calves affected responses to two common husbandry procedures, ear-tagging and disbudding. Forty Holstein-Friesian calves (n = 20/treatment) were exposed to one of two handling treatments daily from 1 to 5 weeks of age: (1) positive (n = 20), involving gentle handling (soft voices, slow movements, patting), and (2) negative (n = 20), involving rough handling (rough voices, rapid movements, pushing). Heart rate (HR), respiration rate (RR) and behaviour (activity, tail flicking) were measured before and after ear-tagging and disbudding (2 days apart). Cortisol was measured at -20 (baseline), 20 and 40 min relative to disbudding time. There were no significant treatment differences in HR, RR or behaviour in response to either procedure. However, the following changes occurred across both treatment groups. HR increased after disbudding (by 14.7 ± 4.0 and 18.6 ± 3.8 bpm, positive and negative, respectively; mean ± s.e.m.) and ear-tagging (by 8.7 ± 3.1 and 10.3 ± 3.0 bpm, positive and negative, respectively). After disbudding, there was an increase in RR (by 8.2 ± 3.4 and 9.3 ± 3.4 breaths/min, positive and negative, respectively), overall activity (by 9.4 ± 1.2 and 9.9 ± 1.3 frequency/min, positive and negative, respectively) and tail flicking (by 13.2 ± 2.8 and 11.2 ± 3.0 frequency/min, positive and negative, respectively), and cortisol increased from baseline at 20 min post procedure (by 10.3 ± 1.1 and 12.3 ± 1.1 nmol/l positive and negative, respectively). Although we recorded significant changes in calf responses during ear-tagging and disbudding, the type of prior handling had no effect on responses. The effects of handling may have been overridden by the degree of pain and/or stress associated with the procedures. Further research is warranted to understand the welfare impact and interaction between previous handling and responses to husbandry procedures.

Using water to cool cattle: behavioral and physiological changes associated with voluntary use of cow showers.

Water is commonly used to cool cattle in summer either at milking or over the feed bunk, but little research has examined how dairy cows voluntarily use water separate from these locations. The objectives were to describe how and when dairy cattle voluntarily used an overhead water source separate from other resources, such as feed, and how use of this water affected behavioral and physiological indicators of heat stress. Half of the 24 nonlactating cattle tested had access to a "cow shower" composed of 2 shower heads activated by a pressure-sensitive floor. All animals were individually housed to prevent competition for access to the shower. Over 5 d in summer (air temperature=25.3±3.3°C, mean ± standard deviation), cattle spent 3.0±2.1 h/24h in the shower, but considerable variability existed between animals (individual daily values ranged from 0.0 to 8.2 h/24h). A portion of this variation can be explained by weather; shower use increased by 0.3h for every 1°C increase in ambient temperature. Cows preferentially used the shower during the daytime, with 89±12% of the time spent in the shower between 1000 and 1900 h. Respiration rate and skin temperature did not differ between treatments [53 vs. 61 breaths/min and 35.0 vs. 35.4°C in shower and control cows, respectively; standard error of the difference (SED)=5.6 breaths/min and 0.49°C]. In contrast, body temperature of cows provided with a shower was 0.2°C lower than control cows in the evening (i.e., 1800 to 2100h; SED=0.11°C). Cows with access to a shower spent half as much time near the water trough than control animals, and this pattern became more pronounced as the temperature-humidity index increased. In addition, cattle showed other behavioral changes to increasing heat load; they spent less time lying when heat load index increased, but the time spent lying, feeding, and standing without feeding did not differ between treatments. Cows had higher respiration rate, skin temperature, and body temperature as heat load index increased, regardless of treatment. These data suggest that cattle, when given the opportunity, will make considerable use of a shower to reduce heat load, but that individuals are highly variable in their use of this resource. The variability between cows indicates that the behavioral response to water is likely an important, but poorly understood, consideration in the design of sprinkler systems used for summer cooling.

Dairy cattle prefer shade over sprinklers: effects on behavior and physiology.

Cattle will readily use shade in warm weather, but less is known about voluntary use of sprinklers. We examined preferences of 96 Holstein-Friesian dairy cows (milk yield: 12.7±3.48 kg per day; mean±SD) for sprinklers, shade, or ambient conditions after walking 2.0 km or 0.3 km before afternoon milking (n=48 cows/distance). Each cow was individually tested on 3 consecutive days with a different paired choice each day: 1) shade or sprinklers, 2) shade or ambient conditions, 3) sprinklers or ambient conditions. Average air temperature during testing was 22.3°C. Cows preferred shade over sprinklers (62 vs. 38% ± 5.0%; mean ± SE) and shade over ambient conditions (65 vs. 35% ± 5.1%; mean±SE). Cows showed no preference between sprinklers and ambient conditions (44% of the cows chose sprinklers, SE=5.3%). The preference for shade over sprinklers and ambient conditions increased with air temperature, solar radiation, and wind speed. Walking distance did not influence the preference for any treatment. Respiration rate was decreased most by sprinklers (38% decrease) but also decreased in shade and ambient conditions (17 and 13% decrease, respectively; standard error of the difference=4.7%). Similarly, surface temperature was decreased most by sprinklers (11.4% decrease), compared with that by shade (1.0% decrease), or that by ambient conditions (1.4% increase; standard error of the difference=1.82%). Furthermore, sprinklers reduced insect avoidance behaviors, including number of tail flicks and hoof stamps. In conclusion, dairy cattle preferred to use shade in summer despite sprinklers being more efficient in decreasing heat load and insect avoidance behavior.

The amount of shade influences the behavior and physiology of dairy cattle.

The objective was to understand how the amount of shade (shade cloth blocking 99% of solar radiation) influenced the behavior and physiology of Holstein-Friesian dairy cattle managed on pasture. We compared behavior, body temperature, and respiration rate of cattle provided with 1 of 3 treatments for 5 d: access to 2.4m(2) or 9.6m(2) shade/cow, or no shade (n=4 groups/treatment, 10 animals/group). Behavioral observations were carried out between 1000 and 1550h. Cows spent more than twice as much time in the larger shade (24 vs. 50% of observations for 2.4m(2) and 9.6m(2) shade/cow, respectively, SED: 1.7%) and engaged in fewer aggressive interactions when more shade was provided (10.7 vs. 3.2 aggressive interactions/m(2) during 5.8h of observation for 2.4m(2) and 9.6m(2) shade/cow, respectively, SED: 3.16 interactions/m(2)). Time around the water trough increased when little or no shade was provided (11, 5, and 2% of observations within 4.5m of water trough for no shade, 2.4m(2), and 9.6m(2) shade/cow, SED: 2.4%). Respiration rate was higher when cows had less shade available (62, 57, and 51 breaths/min for no shade, 2.4m(2), and 9.6m(2) shade/cow, respectively, SED: 2.1 breaths/min). All cows used the shade more when 9.6m(2) shade/cow was provided; simultaneous use was observed in 15 versus 0% of observations in the 9.6m(2) and 2.4m(2) treatments on the warmest day, respectively. Weather conditions influenced both the behavioral and physiological responses, and these changes were more pronounced when less or no shade was available. Cows spent more time in shade and less time lying with increasing heat load. In addition, aggressive interactions in the shade, time around the water trough, mean body temperature, and respiration rate increased with environmental heat load. Our findings highlight the importance of determining and providing an effective amount of shade to cattle.