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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 15.6 m2 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-m2 increase in shade size [standard error (SE) = 1.51%], and all cows were first seen simultaneously using shade when 2 m2/ cow was provided. For every 1-m2 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. [ABSTRACT FROM AUTHOR]

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/24 h for 4 consecutive days (6 h on pasture/24 h). 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: 10.8 h, 24-mm rubber mat: 7.3 h, 12-mm rubber mat: 6.0 h, and concrete: 2.8 h/18 h, standard error of the difference (SED): 0.71 h]. Cows on concrete spent more time lying during the 6 h 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: 12.1 h, 12-mm rubber mat: 11.1 h, 24-mm rubber mat: 11.2 h, and wood chips: 10.7 h/24 h, 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. [ABSTRACT FROM AUTHOR]

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 15 kg 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 β--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 β--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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Deer farmed in New Zealand for venison production are a composite of Cervus elaphus subspecies. Venison production systems target supply of yearling males for slaughter at live-weights of ≥95 kg between 8 and 12 months of age when first antler development is occurring. If the antlers exceed 110 mm they must be removed before the animal can be transported for slaughter which adds handling and costs which some producers consider unnecessary. We hypothesised that there are associations between live-weight and first antler development that are heritable and it would be possible to select sires on the basis of delayed antler development relative to live-weight of their progeny. Antler and live-weight measurements were recorded on 1033 male progeny from three elite recorded red deer breeding herds, DNA pedigree tested as sired by 106 different stags. Spline models were fitted to the antler length and live-weight data over time. Day-of-the-year was read off these splines to define traits of live-weight when antler length reached 50 mm (WA50) or 80 mm (WA80), and antler length when live-weight reached 95 kg (AW95). The predicted traits were analysed using a single-trait animal model incorporating the extended pedigree of the animals involved to calculate three estimated breeding values (EBVs) WA50, WA80 and AW95. The three antler traits had high heritability estimates of 0.67-0.81 with standard errors of 0.10, and were moderately-highly correlated with weaning and yearling live-weight traits. The phenotypic standard deviation of WA80 of 8.35 kg or 8.6% of the mean predicted live-weight and a genetic standard deviation or 6.86 kg indicated good variation within the population, providing scope for genetically improving the current New Zealand breeding herd for delayed antler growth relative to live-weight. Such selection could reduce the number of rising yearling males requiring velvet antler removal prior to slaughter. [ABSTRACT FROM AUTHOR]

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 2.4 m² or 9.6 m² shade/cow, or no shade (n = 4 groups/treatment, 10 animals/group). Behavioral observations were carried out between 1000 and 1550 h. Cows spent more than twice as much time in the larger shade (24 vs. 50% of observations for 2.4 m² and 9.6 m² shade/cow, respectively, SED: 1.7%) and engaged in fewer aggressive interactions when more shade was provided (10.7 vs. 3.2 aggressive interactions/m² during 5.8 h of observation for 2.4 m² and 9.6 m² shade/cow, respectively, SED: 3.16 interactions/m²). Time around the water trough increased when little or no shade was provided (11, 5, and 2% of observations within 4.5 m of water trough for no shade, 2.4 m², and 9.6 m² shade/ cow, SED: 2.4%). Respiration rate was higher when cows had less shade available (62, 57, and 51 breaths/ min for no shade, 2.4 m², and 9.6 m² shade/cow, respectively, SED: 2.1 breaths/min). All cows used the shade more when 9.6 m² shade/cow was provided; simultaneous use was observed in 15 versus 0% of observations in the 9.6 m² and 2.4 m² 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. [ABSTRACT FROM AUTHOR]

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., (The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)