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The New Zealand Government’s National Policy Statement on Fresh Water Management has resulted in increased scrutiny of New Zealand grazing systems with regards to their environmental impact. With this has been greater interest in nitrogen (N) loss mitigation options, including identifying crops with high nutritive value but low protein content. New Zealand data have been collated with key data fields: publication, experiment, site and, crop details and chemical analysis. This paper discusses these data with respect to the range of nutritive values observed in these New Zealand crops and feed supplements, including the implications for reducing N leaching risk. Feeds most likely to result in less urinary nitrogen (UN) excretion, and thus less nitrate (NO3−) leaching, include fodder beet, swedes, turnips, barley and wheat grain. The high soluble sugar and starch content of these feeds will support high animal production but may increase the risk of nutritional disorders. [ABSTRACT FROM PUBLISHER]

Dairy cows are motivated to access dry lying surfaces and will seek protection from wind and rain, but winter conditions may limit these opportunities when cows are managed outdoors. The primary aim of this observational study was to determine the effects of weather and paddock soil conditions on lying behavior of dairy cows managed outdoors during winter and fed crop in situ, a practice occurring in New Zealand with year-round grazing of dairy cows. A secondary aim was to characterize eating and ruminating behaviors during winter weather and paddock soil conditions. Four groups (99 nonlactating, pregnant cows each) were managed on 4 outdoor paddock areas on the same farm; the groups were fed pasture silage and grazed either kale (2 groups) or fodder beet (2 groups). Behaviors were recorded using validated leg-based (lying behavior) and ear-based (eating and ruminating time) accelerometers on 30 focal cows in each group over 32 d. Soil depth and wetness were scored daily at 25 points along 4 transects within each paddock area using recognized technical measures (penetrometer, soil volumetric water content), which were compared with practical tools for farmer use (ruler, moisture meter, percentage of sites in paddock scored as dry, wet, sodden, or with surface water pooling). Rainfall occurred most days during the study (mean 1.6 mm/d; maximum 12.2 mm/d), resulting in wet and muddy paddocks (mud depth with ruler: mean 6 cm, maximum 18 cm; paddock sites scored as wet or sodden: mean 34%, maximum 100%; paddock sites with surface water pooling: mean 27%, maximum 100%). Group lying time was 9.6 ± 2.3 h/d (mean ± standard deviation); however, 21% of cows consistently lay less than 8 h/d (to a minimum of 4.9 h/d). A mixed regression model tested the effects of daily weather and paddock soil conditions on daily lying time, with group as the observational unit, day as repeated measure, crop type as a fixed effect, crop type interactions with explanatory variables, and random intercepts of group and paddock within group. Lying time was less on the day of and day after rainfall (24 and 29 min/d less for 1 mm increase in rainfall, respectively). Two days after rainfall, lying time rebounded to about 1 h longer than before the rainfall. On the day after the heaviest rainfall event, group average lying time was only 2.5 ± 1.9 h/d (mean ± standard deviation); in 2 groups, 30% and 38% of cows, respectively, did not lie down at all for 24 h. Lying time decreased with deteriorating paddock soil conditions, especially with increasing surface water pooling, suggesting that this may be a useful measure to estimate the quality of the lying surface. Descriptively, ruminating time appeared to decrease with increased surface water pooling, possibly due to decreased lying time. Our results demonstrated that dairy cows could experience periods of short or no lying time during inclement weather and muddy paddock soil conditions. Prior rainfall and surface water pooling may be useful measures to determine if lying time, and thus animal welfare, are compromised. [ABSTRACT FROM AUTHOR]

This perspective paper provides industry leaders, researchers and policy developers strategic approaches to ensure that the welfare of dairy cattle is protected at the same time as the industry increases its resilience to climate change. Farm systems and practices will evolve in response to the direct impacts of climate change and/or from responses to climate change, such as mitigation strategies to reduce dairy's greenhouse-gas (GHG) emissions. The five domains framework (nutrition, physical environment, health, behaviour, mental state) was used to assess the potential impacts on animal welfare and strategies to minimise these impacts are outlined. Given that the future climate cannot be certain these approaches can be applied under a range of emissions pathways to (1) ensure that the effects of GHG mitigations on animal welfare are considered during their development, (2) engage with end users and the public to ensure solutions to the effects of climate change and weather variability are accepted by consumers and communities, (3) identify and measure the areas where improved animal health can contribute to reducing GHG emissions from dairy production, (4) ensure those supporting farmers to develop and manage their farm systems understand what constitutes a good quality of life for dairy cattle, (5) ensure effective surveillance of animal disease and monitoring of welfare outcomes and farm-system performance in response to climate change and GHG mitigations. Overall, these strategies require a multidisciplinary co-development approach to ensure that the welfare of dairy cattle is protected at the same time as the industry increases its resilience to the wider impacts of a changing climate. [ABSTRACT FROM AUTHOR]