Biology subjects

Mills, H.

Publications and source records attributed to Mills, H..

3 recordsLinked to original sources

bioRxiv2018

First data-driven approach to using individual cattle weights to estimate mean adult dairy cattle weight in the UK

IntroductionKnowledge of accurate weights of cattle is crucial for effective dosing of individual animals with medicine and for reporting antimicrobial usage metrics, amongst other uses. The most common weight for dairy cattle presented in current literature is 600 kg, but this is not evidenced by data. For the first time, we provide an evidence-based estimate of the average weight of UK dairy cattle to better inform decisions by farmers, veterinarians and the scientific community.\n\nMethodsWe collected data for 2,747 dairy cattle from 20 farms in the UK, 19 using Lely Automatic Milking Systems with weigh floors and 1 using a crush with weigh scales. These data covered farms with different breed types, including Holstein, Friesian, Holstein-Friesian and Jersey, as well as farms with dual purpose breeds and cross-breeds. Data were used to calculate a mean weight for dairy cattle by breed, and a UK-specific mean weight was generated by scaling to UK-specific breed proportions. Trends in weight by lactation number, DIM and production level were also explored using individual cattle-level data.\n\nResultsMean weight for adult dairy cattle included in this study was 617 kg (standard deviation (sd) 85.6 kg). Mean weight varied across breeds, with a range of 466 kg (sd=56.0 kg, Jersey) to 636 kg (sd=84.1, Holsteins). When scaled to UK breed proportions, the estimated mean UK dairy cattle weight was 620 kg. Overall, first-lactation heifers weighed 9% less than cows. Mean weight declined for the first 30 days post-calving, before steadily increasing. For cattle at peak production, mean weight increased with production level.\n\nConclusionsThis study is the first to calculate a mean weight of adult dairy cattle in the UK based on on-farm data. Overall mean weight was higher than that most often proposed in the literature (600 kg). Evidence-informed weights are crucial as the UK works to better monitor and report metrics to monitor antimicrobial use and are useful to farmers and veterinarians to inform dosing decisions.

animal behavior and cognition↗

bioRxiv2017

Evaluation of Metrics for Benchmarking Antimicrobial Use in the United Kingdom Dairy Industry

The issue of antimicrobial resistance is of global concern across human and animal health. In 2016 the UK government committed to new targets for reducing antimicrobial use (AMU) in livestock. However, though a number of metrics for quantifying AMU are defined in the literature, all give slightly different interpretations.\n\nThis paper reviews a selection of metrics for AMU in the dairy industry: total mg, total mg/kg, daily dose and daily course metrics. Although the focus is on their application to the dairy industry, the metrics and issues discussed are relevant across livestock sectors.\n\nIn order to be used widely, a metric should be understandable and relevant to the veterinarians and farmers who are prescribing and using antimicrobials. This means that clear methods, assumptions (and possible biases), standardised values and exceptions should be published for all metrics. Particularly relevant are assumptions around the number and weight of cattle at risk of treatment and definitions of dose rates and course lengths; incorrect assumptions can mean metrics over- or under-represent AMU.\n\nThe authors recommend that the UK dairy industry work towards UK-specific metrics using UK-specific medicine dose and course regimens as well as cattle weights in order to monitor trends nationally.

epidemiology↗

bioRxiv2017

The effect of a lifestyle intervention in obese pregnant women on change in gestational metabolic profiles: findings form the UK Pregnancies Better Eating and Activity Trial (UPBEAT) RCT.

Background: Pregnancy metabolic disruption is believed to be enhanced in obese women and lead to adverse outcomes in them and their offspring. The UK Pregnancies Better Eating and Activity Trial (UPBEAT), a randomised controlled trial of a lifestyle intervention in obese pregnant women, has already been shown to improve diet and physical activity. We used UPBEAT to determine (a) the magnitude of change in metabolic profiles in obese pregnant women and (b) the impact of a lifestyle intervention that successfully improved diet and physical activity on these profiles. Methods: Detailed targeted metabolic profiling, with quantification of 158 metabolic features (129 lipid measures, 9 glycerides and phospholipids, and 20 low-molecular weight metabolites) was completed on three occasions (~17-, 28- and 35-weeks of gestation) in the UPBEAT participants using NMR. Random intercept and random slope models were used to quantify metabolite changes in obese women using the control (usual care) group only (N = 577). The effect of the intervention was determined by comparing rates of metabolite change between those randomised to intervention and usual care, using intention to treat analyses (N = 1158). Results: There were adverse changes across pregnancy in most lipoprotein subclasses, lipids, glycerides, phospholipids, several fatty acids and glucose. All extremely large, very large, large, medium, small and very small VLDL particles increased by 2 to 3 standard deviation units (SD), with IDL, and large, medium and small LDL particles increasing by 1 to 2SD, between 16- and 36-weeks. Triglycerides increased by 3 to 4SD and glucose increased by 2SD, with more modest changes in other metabolites. The intervention reduced the rate of increase in extremely large, very large, large and medium VLDL, in particular those containing triglycerides. Triglyceride to phosphoglyceride ratio was reduced and there were improvements in fatty acid profiles (increases in the proportion of all fatty acids that were linoleic, omega-6 and polyunsaturated and decreases in the proportion of saturated). Conclusion: Systemic metabolism is markedly disrupted in obese pregnant women, but a lifestyle intervention that improved their diet and physical activity has beneficial effects on some of these profiles; these effects might have long-term benefit. Clinical trial registration ID # ISRCTN89971375.

clinical trials↗