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Hexavalent chromium (Cr6+) is a toxic carcinogenic pollutant that might be released by the mining and processing of ultramafic rocks and nickel laterites and which requires permanent removal from the contaminated biosphere. Ultramafic material can also serve as a feedstock for the sequestration of CO2 resulting from the growth of new minerals, raising the intriguing proposition of integrated sequestration of both pollutants, CO2 and chromium, into magnesium carbonates. Such a synergistic process downstream of ore recovery and mineral processing could be an elegant proposition for more sustainable utilisation and management of the Earth's resources. We have therefore carried out an experimental and microanalytical study to investigate potentially suitable carbonate minerals. Uptake of chromium in carbonate phases was determined, followed by identification of the crystalline phases and characterisation of the local structural environment around the incorporated chromium centres. The results suggest that neither nesquehonite nor hydromagnesite have the structural capacity to incorporate Cr6+ or Cr3+ significantly at room temperature. We therefore propose that further research into this technology should focus on laboratory assessments of other phases, such as layered double hyroxides, that have a natural structural capacity to uptake both chromium and CO2.
The relationship between dietary habits and microbiota composition during adolescence has not been well examined. This is a crucial knowledge gap to fill considering that diet–microbiota interactions influence neurodevelopment, immune system maturation and metabolic regulation. This study examined the associations between diet and the gut microbiota in a school-based sample of 136 adolescents (Mage = 12·1 years; age range 11–13 years; 48 % female; 47 % Black, 38 % non-Hispanic White, 15 % Hispanic or other minorities) from urban, suburban and rural areas in the Southeast USA. Adolescents completed the Rapid Eating Assessment for Participants and provided stool samples for 16S ribosomal RNA gene sequencing. Parents reported their child and family socio-demographic characteristics. The associations between diet and socio-demographics with gut microbiota diversity and abundance were analysed using multivariable regression models. Child race and ethnicity, sex, socio-economic status and geographic locale contributed to variation within microbiota composition (β-diversity). Greater consumption of processed meat was associated with a lower microbial α-diversity after adjusting for socio-demographic variables. Multi-adjusted models showed that frequent consumption of nutrient-poor, energy-dense foods (e.g. sugar-sweetened beverages, fried foods, sweets) was negatively associated with abundances of genera in the family Lachnospiraceae (Anaerostipes, Fusicatenibacter and Roseburia), which are thought to play a beneficial role in host health through their production of short-chain fatty acids (SCFAs). These results provide new insights into the complex relationships among socio-demographic factors, diet and gut microbiota during adolescence. Adolescence may represent a critical window of opportunity to promote healthy eating practices that shape a homoeostatic gut microbiota with life-long benefits.
The number of incidences of violence and restrictive practices within acute inpatient psychiatric wards are significantly high which makes these units less conducive for recovery and less therapeutic. Staff and patient survey results highlighted their concerns and their desire to have a safe environment to work and a less volatile therapeutic environment.
Objectives
The aim of this QI project was to reduce violence and restrictive practices within acute inpatient units.
Methods
PDSA cycle was used to achieve the objective.
Plan
Primary and secondary drivers were identified and were illustrated using driver diagram. Three units were identified for pilot study. The group has agreed to collate change ideas from service users and restraint data from internal system will be used to review the impact of changes.
Do
Meeting were conducted with service users from these units to populate change ideas. Additionally, the Acute care group also outlined some practice related change ideas such as enhanced recruitment of substantive staff, safety pods, introducing safety huddles, revising therapeutic planner, developing safe care champions and inclusion of professionals from various disciplines such as drama therapist, sports technicians and peer support workers that are traditionally not included in MDT. The change ideas were implemented in one of the selected units.
Study
The group reviewed the feasibility of change ideas and agreed on change ideas that got more support from service users which were projectors to play music, soothing DVDs to assist with relaxation and ear defenders.
Action
All change ideas were implemented on the pilot units.
Results
The QI project has enabled the trust to reduce the number of violence and restrictive practices on all the three units, with a team approach and using a multipronged approach, co-production and openness key to positive results.
In due course we also liaised with the wards to get qualitative feedback from the service users to see how they felt about this new change.
A year after the initial data was collected, to see if there had been the intended 50 per cent reduction in violence and restrictive practices. The team were delighted to find that they had exceeded this aim with a 56 per cent reduction with only 12.3 incidents being reported over the 3-month period.
Conclusions
The QI project on pilot wards have enabled to reduce the number of violence and restrictive practices on all the three units.
Team approach and using a multipronged approach, coproduction and openness key to positive results.
The next step is to implement these change ideas on all other units and looking into the economic value and saving as part of this project, given lesser incidents and staff requirements.
OBJECTIVES/GOALS: To evaluate the clarity of plain-language informed consent forms (ICF) created using a browser-based tool called the ICF Navigator, we solicited feedback from two community review boards (CRB) to ensure the resulting ICF met the informational needs of all potential participants, including those with limited health literacy skills. METHODS/STUDY POPULATION: Community-engaged research highlights the importance of involving community members in the planning and execution of translational research projects. Virtual discussions were held to elicit feedback from two separate CRBs on the understandability of an ICF that was generated using an online, browser-based tool that we designed to aid researchers in the creation of plain-language ICFs. CRBs included representation of diverse communities from across the state of Arkansas, including individuals who may have limited health literacy skills, those with and without prior experience participating in clinical research projects, members living in rural and urban settings, and those whose race or ethnicity have been traditionally underrepresented among clinical research participants. RESULTS/ANTICIPATED RESULTS: CRB feedback was used to inform actionable improvements to the tool, such as removing content redundancies and embedding tips to guide researchers on how best to optimize the clarity and understandability of resulting ICFs. Program refinements in response to the feedback have been implemented and will be evaluated in another round of CRB discussions in early 2023. Feedback from this follow-up CRB session will also be presented in addition to a discussion of how the feedback was used to improve the online tool, which will ultimately be available for free use by other institutions. DISCUSSION/SIGNIFICANCE: The use of community feedback to optimize the functionality of the ICF Navigator demonstrates the value of CRBs for ensuring that ICFs are culturally salient and readily understandable by all potential research participants, particularly those who may have limited health literacy skills, thereby promoting more equitable opportunities for all.
Despite evidence for its efficacy, exposure therapy for anxiety is rarely used in routine care settings. Efforts to address one major barrier to its use – therapists’ negative beliefs about exposure – have included therapist-level implementation strategies, such as training and consultation. Experiential training, in which therapists themselves undergo exposures, has recently demonstrated feasibility, acceptability and preliminary effectiveness for increasing exposure use.
Aims:
This study aimed to assess: (1) therapists’ perceptions of experiential training and (2) barriers and facilitators to implementing exposure following training.
Method:
Therapists who underwent experiential training (n=12) completed qualitative interviews and quantitative questionnaires. Interviews were coded using an integrated approach, combining both inductive and deductive approaches. Mixed methods analyses examined how themes varied by practice setting (community mental health versus private practice) and exposure use.
Results:
Results highlight how therapist-level factors, such as clinician self-efficacy, interact with inner- and outer-setting factors. Participants reported positive perceptions of exposure after training; they noted that directly addressing myths about exposure and experiencing exposures themselves improved their attitudes toward exposure. Consistent with prior literature, issues such as insufficient supervisory support, organizational constraints, and client characteristics made it challenging to implement exposures.
Discussion:
Results highlight the benefits of experiential training, while also highlighting the need to consider contextual determinants. Differences in responses across practice settings highlight areas for intervention and the importance of tailoring implementation strategies. Barriers that were specific to therapists who did not use exposure (e.g. hesitancy about its appropriateness for most clients) point to directions for future implementation efforts.
Ancient Egyptian art features many carefully observed depictions of wild animals and birds. A famous example is the late Eighteenth Dynasty (fourteenth-century BC) wall paintings of the Green Room in the North Palace at Amarna, where naturalistic depictions of birds feature prominently. Their taxonomic identity, however, is not resolved in all cases. Here, the authors revisit the facsimiles produced in the 1920s by Nina de Garis Davies. Mindful of previous works, taphonomy and the interplay between naturalistic observation and artistic licence, they employ ornithological resources to conduct a qualitative assessment and propose a parsimonious scheme of identifications, relating the results to long-standing questions concerning ecological and stylistic aspects in the artwork.
Informed consent forms (ICFs) and practices vary widely across institutions. This project expands on previous work at the University of Arkansas for Medical Sciences (UAMS) Center for Health Literacy to develop a plain language ICF template. Our interdisciplinary team of researchers, comprised of biomedical informaticists, health literacy experts, and stakeholders in the Institutional Review Board (IRB) process, has developed the ICF Navigator, a novel tool to facilitate the creation of plain language ICFs that comply with all relevant regulatory requirements.
Methods:
Our team first developed requirements for the ICF Navigator tool. The tool was then implemented by a technical team of informaticists and software developers, in consultation with an informed consent legal expert. We developed and formalized a detailed knowledge map modeling regulatory requirements for ICFs, which drives workflows within the tool.
Results:
The ICF Navigator is a web-based tool that guides researchers through creating an ICF as they answer questions about their project. The navigator uses those responses to produce a clear and compliant ICF, displaying a real-time preview of the final form as content is added. Versioning and edits can be tracked to facilitate collaborative revisions by the research team and communication with the IRB. The navigator helps guide the creation of study-specific language, ensures compliance with regulatory requirements, and ensures that the resulting ICF is easy to read and understand.
Conclusion:
The ICF Navigator is an innovative, customizable, open-source software tool that helps researchers produce custom readable and compliant ICFs for research studies involving human subjects.
This study aimed to evaluate the effect of an extended voluntary waiting period (VWP) on SCC, SCC elevations and clinical mastitis incidence during the complete lactation and the first 6 weeks of the next lactation. Holstein-Friesian dairy cows (N = 154) were blocked for parity, expected milk yield, calving season and breeding value for persistency and were randomly distributed across 3 VWP (50, 125, or 200 d: VWP-50, VWP-125, VWP-200). Cows were monitored from calving until 6 weeks into the next lactation, or until culling. An elevation of SCC in milk was defined as SCC in milk ≥200 000 cells/ml after two previous weeks with SCC < 200 000 cells/ml. Over the complete lactation, extending the VWP did not affect SCC elevations and the occurrence of clinical mastitis per lactation or per cow per year. There was no clear effect of VWP length on SCC in the complete lactation, except that multiparous cows in VWP-125 had a higher SCC compared with multiparous cows in VWP-50. Dry-off antibiotic usage per cow per year was lower in VWP-200 compared with VWP-50 for multiparous cows. In the first 6 weeks of the next lactation, cows in VWP-200 had a higher SCC compared with cows in VWP-50, with no effect of VWP on the number of elevations of SCC or the occurrence of clinical mastitis. Extending the VWP may therefore be used to reduce the frequency of transition periods and the associated use of dry-cow antibiotics, with limited impact on udder health, and a similar occurrence of SCC elevations and clinical mastitis per year.
This study presents the results of ancient DNA analyses of eight snakehead (Channa sp.) bones from the Market Street Chinatown, a nineteenth-century Chinese diaspora archaeological site in San Jose, California. The sequences of a short stretch of the mitochondrial DNA identify the Market Street Chinatown snakeheads as Giant Snakehead (Channa micropeltes), a species native to Southeast Asia. These results provide the first archaeological evidence of the nineteenth-century trade of Asian freshwater fishes to North America, and they reveal that preserved fish products from throughout the Pacific World were readily distributed across the Chinese diaspora. We place our findings within the broader context of nineteenth-century Chinese migration to show how the common Chinese small shareholding business model and access to trade connections facilitated by Chinese-operated import/export firms known as jinshanzhuang allowed Chinese fishers to be successful across the Pacific World. Finally, we suggest avenues for future study by comparing Chinese migration-based, flexible fishing strategies using generalist methods with the highly specialized collection and trade of species like Atlantic Cod (Gadus morhua) in the North Atlantic.
People living in Mesoamerica and what is now the eastern and southwestern United States used turkeys (Meleagris gallopavo) as sources of meat, eggs, bones, and feathers. Turkey husbandry and domestication are confirmed in two of these regions (Mesoamerica and the American Southwest), but human-turkey interactions in Eastern North American (eastern United States and Canada) are not fully explored. We apply stable isotope (δ13C, δ15N) and ancient mitochondrial DNA analyses to archaeofaunal samples from seven sites in the southeastern United States to test whether turkeys were managed or captively reared. These combined data do not support prolonged or intensive captive rearing of turkeys, and evidence for less intensive management is ambiguous. More research is warranted to determine whether people managed turkeys in these areas, and whether this is generalizable. Determining whether turkeys were managed or reared in the southeastern United States helps define cultural and environmental factors related to turkey management or husbandry throughout North America. This inquiry contributes to discussion of the roles of intensified human-animal interactions in animal domestication.
Few studies have examined the healthy eating environments within the Australian out of school hours care (OSHC) setting. This study aims to describe healthy eating environments, consisting of: (a) the alignment of provided food and beverages to Australian Dietary Guidelines; (b) healthy eating promotion practices; (c) nutrition education through cooking experiences; (d) staff role modelling healthy eating and (e) regular water availability.
Design:
A cross-sectional study was conducted using direct observations and the validated System for Observing Staff Promotion of Activity and Nutrition (SOSPAN) tool.
Setting:
OSHC located in urban and semi-rural regions of NSW, Australia.
Participants:
Staff (151) and children (1549) attending twelve OSHC services operating in the hours after school.
Results:
Fifty per cent (50 %) of services offered fruits and 100 % offered water as a part of the afternoon snack on all four observation days. Discretionary foods were offered on more days compared to vegetables (+1·9/d, P = 0·009), lean meats (+2·7/d, P =·0 004) and wholegrains (+2·8/d, P = 0 002). Staff promoted healthy eating on 15 % of days, sat and ate with children 52 %, consumed high sugar drinks 15 % and ate discretionary foods in front of children 8 % of days, respectively. No opportunities for cooking or nutrition education were observed.
Conclusion:
Afternoon snacks regularly contained fruits and water. Opportunities exist to improve the frequency by which vegetables, wholegrains and lean meats are offered in addition to staff healthy eating promotion behaviours. Future research is warranted to further explore healthy eating behaviours, practices and policies within the after-school sector.
Integration of depression treatment into primary care could improve patient outcomes in low-resource settings. Losses along the depression care cascade limit integrated service effectiveness. This study identified patient-level factors that predicted detection of depressive symptoms by nurses, referral for depression treatment, and uptake of counseling, as part of integrated care in KwaZulu-Natal, South Africa.
Methods
This was an analysis of baseline data from a prospective cohort. Participants were adult patients with at least moderate depressive symptoms at primary care facilities in Amajuba, KwaZulu-Natal, South Africa. Participants were screened for depressive symptoms prior to routine assessment by a nurse. Generalized linear mixed-effects models were used to estimate associations between patient characteristics and service delivery outcomes.
Results
Data from 412 participants were analyzed. Nurses successfully detected depressive symptoms in 208 [50.5%, 95% confidence interval (CI) 38.9–62.0] participants; of these, they referred 76 (36.5%, 95% CI 20.3–56.5) for depression treatment; of these, 18 (23.7%, 95% CI 10.7–44.6) attended at least one session of depression counseling. Depressive symptom severity, alcohol use severity, and perceived stress were associated with detection. Similar factors did not drive referral or counseling uptake.
Conclusions
Nurses detected patients with depressive symptoms at rates comparable to primary care providers in high-resource settings, though gaps in referral and uptake persist. Nurses were more likely to detect symptoms among patients in more severe mental distress. Implementation strategies for integrated mental health care in low-resource settings should target improved rates of detection, referral, and uptake.
Selection for prolificacy in sows has resulted in higher metabolic demands during lactation. In addition, modern sows have an increased genetic merit for leanness. Consequently, sow metabolism during lactation has changed, possibly affecting milk production and litter weight gain. The aim of this study was to investigate the effect of lactational feed intake on milk production and relations between mobilization of body tissues (adipose tissue or skeletal muscle) and milk production in modern sows with a different lactational feed intake. A total of 36 primiparous sows were used, which were either full-fed (6.5 kg/day) or restricted-fed (3.25 kg/day) during the last 2 weeks of a 24-day lactation. Restricted-fed sows had a lower milk fat percentage at weaning and a lower litter weight gain and estimated milk fat and protein production in the last week of lactation. Next, several relations between sow body condition (loss) and milk production variables were identified. Sow BW, loin muscle depth and backfat depth at parturition were positively related to milk fat production in the last week of lactation. In addition, milk fat production was related to the backfat depth loss while milk protein production was related to the loin muscle depth loss during lactation. Backfat depth and loin muscle depth at parturition were positively related to lactational backfat depth loss or muscle depth loss, respectively. Together, results suggest that sows which have more available resources during lactation, either from a higher amount of body tissues at parturition or from an increased feed intake during lactation, direct more energy toward milk production to support a higher litter weight gain. In addition, results show that the type of milk nutrients that sows produce (i.e. milk fat or milk protein) is highly related to the type of body tissues that are mobilized during lactation. Interestingly, relations between sow body condition and milk production were all independent of feed level during lactation. Sow management strategies to increase milk production and litter growth in modern sows may focus on improving sow body condition at the start of lactation or increasing feed intake during lactation.
Reintroduction to, or reinforcement of, threatened wild populations are commonly used conservation strategies. Reintroductions of the Southern Ground-hornbill Bucorvus leadbeateri have been tested as a potential conservation tool for this vulnerable species since 1995. Forty-two individuals have been reintroduced under varying management strategies. We analysed the outcomes of these attempts to assess which factors contributed most to success or failure. The species exhibits complex social learning and hierarchy, and is long-lived, with delayed sexual maturity. Immediate survival was significantly affected by the season in which the release was done and by the quality of the released birds. The best-quality release birds were reared with wild behavioural characteristics and were well-socialised to captive conspecifics prior to being placed into managed groups (‘bush schools’), where social learning was led by an experienced, wild alpha male. Once reintroduced birds had survived their first year after release, continued wild experience and wild mentorship significantly affected their survival. Since sample sizes limited the rigour of some statistical analyses, other factors were considered that may also determine success. These quasi-experimental reintroductions revealed novel threats to the species, such as the importance of a nest to group cohesion, that harvested second-hatched chicks provide viable release birds, which essentially doubles wild productivity, and that reintroductions generate valuable civil society awareness of the plight of the species.
There has been increasing interest in identifying individuals with pathological healthy eating behaviours, or orthorexia nervosa (ON). This study aimed to investigate the validity (construct- and criterion-related) and reliability (internal consistency) of the Eating Habits Questionnaire (EHQ) as a measure of ON. A secondary aim was to examine how the EHQ would predict a distinct feature of ON, adequate dietary intake.
Design:
Cross-sectional online questionnaire incorporating existing measures of ON and dietary intake.
Setting:
Participants were recruited online via social media and a university’s research webpage.
Participants:
Women (n 286) ranging in age from 17 to 73 years.
Results:
Exploratory factor analysis established that the EHQ represented four ON dimensions (Healthy Eating Cognitions, Dietary Restriction, Diet Superiority and Social Impairment), inconsistent with the scale’s original three dimensions (Problems, Knowledge and Feelings). Cronbach’s α coefficients ranged from 0·72 to 0·80 for the four subscales and was 0·89 for the total EHQ scale. Criterion-related validity revealed a significant moderate to strong correlation (r = −0·54, P < 0·001) between the EHQ and ORTO-10 (a ten-item version of ORTO-15). The EHQ, particularly the EHQ–Diet superiority subscale, was found to be predictive of better, as opposed to, poorer dietary adequacy.
Conclusions:
Findings suggest that improvements still need to be made to the EHQ for it to be a valid and reliable measure of ON. Ideally, new assessment tools based on established diagnostic criteria are needed to advance our understanding of ON.
We systematically reviewed implementation research targeting depression interventions in low- and middle-income countries (LMICs) to assess gaps in methodological coverage.
Methods
PubMed, CINAHL, PsycINFO, and EMBASE were searched for evaluations of depression interventions in LMICs reporting at least one implementation outcome published through March 2019.
Results
A total of 8714 studies were screened, 759 were assessed for eligibility, and 79 studies met inclusion criteria. Common implementation outcomes reported were acceptability (n = 50; 63.3%), feasibility (n = 28; 35.4%), and fidelity (n = 18; 22.8%). Only four studies (5.1%) reported adoption or penetration, and three (3.8%) reported sustainability. The Sub-Saharan Africa region (n = 29; 36.7%) had the most studies. The majority of studies (n = 59; 74.7%) reported outcomes for a depression intervention implemented in pilot researcher-controlled settings. Studies commonly focused on Hybrid Type-1 effectiveness-implementation designs (n = 53; 67.1), followed by Hybrid Type-3 (n = 16; 20.3%). Only 21 studies (26.6%) tested an implementation strategy, with the most common being revising professional roles (n = 10; 47.6%). The most common intervention modality was individual psychotherapy (n = 30; 38.0%). Common study designs were mixed methods (n = 27; 34.2%), quasi-experimental uncontrolled pre-post (n = 17; 21.5%), and individual randomized trials (n = 16; 20.3).
Conclusions
Existing research has focused on early-stage implementation outcomes. Most studies have utilized Hybrid Type-1 designs, with the primary aim to test intervention effectiveness delivered in researcher-controlled settings. Future research should focus on testing and optimizing implementation strategies to promote scale-up of evidence-based depression interventions in routine care. These studies should use high-quality pragmatic designs and focus on later-stage implementation outcomes such as cost, penetration, and sustainability.
We present a broad study of linear, clustered, noble gas puffs irradiated with the frequency doubled (527 nm) Titan laser at Lawrence Livermore National Laboratory. Pure Ar, Kr, and Xe clustered gas puffs, as well as two mixed-gas puffs consisting of KrAr and XeKrAr gases, make up the targets. Characterization experiments to determine gas-puff density show that varying the experimental parameter gas-delay timing (the delay between gas puff initialization and laser-gas-puff interaction) provides a simple control over the gas-puff density. X-ray emission (>1.4 keV) is studied as a function of gas composition, density, and delay timing. Xe gas puffs produce the strongest peak radiation in the several keV spectral region. The emitted radiation was found to be anisotropic, with smaller X-ray flux observed in the direction perpendicular to both laser beam propagation and polarization directions. The degree of anisotropy is independent of gas target type but increases with photon energy. X-ray spectroscopic measurements estimate plasma parameters and highlight their difference with previous studies. Electron beams with energy in excess of 72 keV are present in the noble gas-puff plasmas and results indicate that Ar plays a key role in their production. A drastic increase in harder X-ray emissions (X-ray flash effect) and multi-MeV electron-beam generation from Xe gas-puff plasma occurred when the laser beam was focused on the front edge of the linear gas puff.
Shortening or omitting the dry period improves the energy balance and metabolic status of dairy cows in early lactation. Metabolic, behaviour and welfare effects throughout lactation, however, are unclear. The current paper reviews long-term metabolic and welfare consequences of short and no dry period, as well as feeding strategies and individual cow characteristics that could support in optimising management of cows with a short or no dry period. The paper will conclude with impacts of short and no dry periods at herd level and in practice. Energy balance after no or a short dry period is more positive during the complete subsequent lactation. After the initial improvement in early lactation, cows after no dry period tend to fatten and may have a too low lactation persistency to be continuously milked until the onset of the subsequent lactation. Reducing dietary energy level for cows with no dry period reduced fattening during the complete lactation but did not improve lactation persistency. Feeding a more lipogenic diet for cows with a short or no dry period did not affect the energy balance or lactation persistency during the complete lactation, although a lipogenic diet resulted in lower plasma insulin and IGF-1 concentration and greater plasma growth hormone concentration, compared with a glucogenic diet. Effects of dry period length on udder health are ambiguous, whereas short and no dry periods improved fertility in most studies. Omission of the dry period changed behaviour of cows both before and after calving, with a longer lying time and greater feed intake after calving, suggesting a better adaptation to a new lactation. Individual cow characteristics like parity, genotype, prepartum body condition score, and milk yield level determined the metabolic response of cows to a short or no dry period. In conclusion, short or no dry periods increase the energy balance in the complete lactation. Feeding strategies can be used to limit fattening of cows with no or short dry period, but the studied feeding strategies did not increase lactation persistency. Improved fertility and behavioural changes around calving suggest a better adaptation to a new lactation in case of no dry period. Customised dry period lengths for individual cows could improve metabolic status of cows at risk of a severe negative energy balance while minimising milk losses.
The transition period is the most critical period in the lactation cycle of dairy cows. Extended lactations reduce the frequency of transition periods, the number of calves and the related labour for farmers. This study aimed to assess the impact of 2 and 4 months extended lactations on milk yield and net partial cash flow (NPCF) at herd level, and on greenhouse gas (GHG) emissions per unit of fat- and protein-corrected milk (FPCM), using a stochastic simulation model. The model simulated individual lactations for 100 herds of 100 cows with a baseline lactation length (BL), and for 100 herds with lactations extended by 2 or 4 months for all cows (All+2 and All+4), or for heifers only (H+2 and H+4). Baseline lactation length herds produced 887 t (SD: 13) milk/year. The NPCF, based on revenues for milk, surplus calves and culled cows, and costs for feed, artificial insemination, calving management and rearing of youngstock, was k€174 (SD: 4)/BL herd per year. Extended lactations reduced milk yield of the herd by 4.1% for All+2, 6.9% for All+4, 1.1% for H+2 and 2.2% for H+4, and reduced the NPCF per herd per year by k€7 for All+2, k€12 for All+4, k€2 for H+2 and k€4 for H+4 compared with BL herds. Extended lactations increased GHG emissions in CO2-equivalents per t FPCM by 1.0% for All+2, by 1.7% for All+4, by 0.2% for H+2 and by 0.4% for H+4, but this could be compensated by an increase in lifespan of dairy cows. Subsequently, production level and lactation persistency were increased to assess the importance of these aspects for the impact of extended lactations. The increase in production level and lactation persistency increased milk production of BL herds by 30%. Moreover, reductions in milk yield for All+2 and All+4 compared with BL herds were only 0.7% and 1.1% per year, and milk yield in H+2 and H+4 herds was similar to BL herds. The resulting NPCF was equal to BL for All+2 and All+4 and increased by k€1 for H+2 and H+4 due to lower costs for insemination and calving management. Moreover, GHG emissions per t FPCM were equal to BL herds or reduced (0% to −0.3%) when lactations were extended. We concluded that, depending on lactation persistency, extending lactations of dairy cows can have a positive or negative impact on the NPCF and GHG emissions of milk production.
Blood metabolite and hormone concentrations are indicative of metabolic status, but blood sampling and analysis is invasive and time-consuming. Monitoring behavior can be done automatically, and behaviors may also be used as indicators of metabolic status. The aim of this study was to analyze the relationships between metabolic status and feeding behavior, lying behavior, motion index and steps of dairy cows in week 4 postpartum. Behavioral data from 81 Holstein-Friesian cows were collected using computerized feeders and accelerometers, and blood samples were collected for analysis of free-fatty acid (FFA), β-hydroxybutyrate (BHB), glucose, insulin, IGF-1 and growth hormone (GH) concentrations. First, cluster analysis was performed to categorize cows as having poor, average, good or very good metabolic status based on their plasma FFA, BHB, glucose, insulin, IGF-1 and GH concentration. Subsequently, the performance and behavior of cows in clusters with poor, average and good metabolic status were compared using GLM. Cows with a poor or average metabolic status tended to have greater fat-and-protein-corrected milk yield than cows with good metabolic status. Furthermore, cows with a poor metabolic status had a lower energy balance and dry matter intake (DMI) than cows with an average or good metabolic status and had a lower number of meals than cows with good metabolic status. Daily number of visits to the feeder and lying time tended to be positively related with metabolic status. Feeding rate (kg/min), daily meal time (min/day), number of lying bouts per day, steps and motion index were not related with metabolic status. In conclusion, better metabolic status in dairy cows in early lactation was associated with a greater DMI, increased feeding activity and a tendency to more time spent lying, compared with poor metabolic status. These results suggest that compromised metabolic status is reflected in altered cow’s behavior in week 4 of lactation.