Pen-Based Swine Oral Fluid Samples Contain Both Environmental and Pig-Derived Targets.

Laboratory methods for detecting specific pathogens in oral fluids are widely reported, but there is little research on the oral fluid sampling process itself. In this study, a fluorescent tracer (diluted red food coloring) was used to test the transfer of a target directly from pigs or indirectly from the environment to pen-based oral fluid samples. Pens of ~30, ~60, and ~125 14-week-old pigs (32 pens/size) on commercial swine farms received one of two treatments: (1) pig exposure, i.e., ~3.5 mL of tracer solution sprayed into the mouth of 10% of the pigs in the pen; (2) environmental exposure, i.e., 20 mL of tracer solution was poured on the floor in the center of the pen. Oral fluids collected one day prior to treatment (baseline fluorescence control) and immediately after treatment were tested for fluorescence. Data were evaluated by receiver operating characteristic (ROC) analysis, with Youden's J statistic used to set a threshold. Pretreatment oral fluid samples with fluorescence responses above the ROC threshold were removed from further analysis (7 of 96 samples). Based on the ROC analyses, oral fluid samples from 78 of 89 pens (87.6%), contained red food coloring, including 43 of 47 (91.5%) pens receiving pig exposure and 35 of 42 (83.3%) pens receiving environmental exposure. Thus, oral fluid samples contain both pig-derived and environmental targets. This methodology provides a safe and quantifiable method to evaluate oral fluid sampling vis-à-vis pen behavior, pen size, sampling protocol, and target distribution in the pen.

Estimating the effectiveness of control actions on African swine fever transmission in commercial swine populations in the United States.

Given the proximity of African swine fever (ASF) to the U.S., there is an urgent need to better understand the possible dissemination pathways of the virus within the U.S. swine industry and to evaluate mitigation strategies. Here, we extended PigSpread, a farm-level spatially-explicit stochastic compartmental transmission model incorporating six transmission routes including between-farm swine movements, vehicle movements, and local spread, to model the dissemination of ASF. We then examined the effectiveness of control actions similar to the ASF national response plan. The average number of secondary infections during the first 60 days of the outbreak was 49 finisher farms, 17 nursery farms, 5 sow farms, and less than one farm in other production types. The between-farm movements of swine were the predominant route of ASF transmission with an average contribution of 71.1%, while local spread and movement of vehicles were less critical with average contributions of 14.6% and 14.4%. We demonstrated that the combination of quarantine, depopulation, movement restrictions, contact tracing, and enhanced surveillance, was the most effective mitigation strategy, resulting in an average reduction of 79.0% of secondary cases by day 140 of the outbreak. Implementing these control actions led to a median of 495,619 depopulated animals, 357,789 diagnostic tests, and 54,522 movement permits. Our results suggest that the successful elimination of an ASF outbreak is likely to require the deployment of all control actions listed in the ASF national response plan for more than 140 days, as well as estimating the resources needed for depopulation, testing, and movement permits under these controls.

Network analysis of live pig movements in North Macedonia: Pathways for disease spread.

Globalization of trade, and the interconnectivity of animal production systems, continues to challenge efforts to control disease. A better understanding of trade networks supports development of more effective strategies for mitigation for transboundary diseases like African swine fever (ASF), classical swine fever (CSF), and foot-and-mouth disease (FMD). North Macedonia, bordered to the north and east by countries with ongoing ASF outbreaks, recently reported its first incursion of ASF. This study aimed to describe the distribution of pigs and pig farms in North Macedonia, and to characterize the live pig movement network. Network analyses on movement data from 2017 to 2019 were performed for each year separately, and consistently described weakly connected components with a few primary hubs that most nodes shipped to. In 2019, the network demonstrated a marked decrease in betweenness and increase in communities. Most shipments occurred within 50 km, with movements <6 km being the most common (22.5%). Nodes with the highest indegree and outdegree were consistent across years, despite a large turnover among smallholder farms. Movements to slaughterhouses predominated (85.6%), with movements between farms (5.4%) and movements to market (5.8%) playing a lesser role. This description of North Macedonia's live pig movement network should enable implementation of more efficient and cost-effective mitigation efforts strategies in country, and inform targeted educational outreach, and provide data for future disease modeling, in the region.

Descriptive and Multivariate Analysis of the Pig Sector in North Macedonia and Its Implications for African Swine Fever Transmission.

North Macedonia, a country in the Balkan region of Europe, is currently bordered to the north and east by countries with active African swine fever (ASF) outbreaks. The predominantly traditional backyard pig farming sector in this country is under imminent threat of disease incursion. The characteristics and practices of such sectors have rarely been described, and thus the implications for these factors on disease introduction and spread are poorly understood. Using a semi-structured questionnaire, 457 pig producers were interviewed, providing information on 77.7% of the pig population in North Macedonia. In addition, a pilot study of 25 pig producers in Kosovo was performed. This study aimed to provide a detailed description of the North Macedonian pig sector, to make comparisons with nearby Kosovo, and to identify areas with high-risk practices for targeted mitigation. Descriptive data were summarized. Results of the questionnaire were used to identify farm-level risk factors for disease introduction. These factors were used in the calculation of a biosecurity risk score. Kernel density estimation methods were used to generate density maps highlighting areas where the risk of disease introduction was particularly concentrated. Multiple correspondence analysis with hierarchical clustering on principal components was used to explore patterns in farm practices. Results show that farms were predominantly small-scale with high rates of turnover. Pig movement was predominantly local. The highest biosecurity risk scores were localized in the eastern regions of North Macedonia, concerningly the same regions with the highest frequency of wild boar sightings. Veterinarians were highly regarded, regularly utilized, and trusted sources of information. Practices that should be targeted for improvement include isolation of new pigs, and consistent application of basic sanitary practices including washing hands, use of disinfection mats, and separation of clean and dirty areas. This study provides the most complete description of the North Macedonian pig sector currently available. It also identifies regions and practices that could be targeted to mitigate the risk of disease incursion and spread. These results represent the first steps to quantify biosecurity gaps and high-risk behaviors in North Macedonia, providing baseline information to design risk-based, more cost-effective, prevention, surveillance, and control strategies.

Impacts from Wildfires on Livestock Health and Production: Producer Perspectives.

Wildfires are increasing in frequency and severity across the Western United States. However, there is limited information available on the impacts these fires are having on the livelihood of livestock producers and their animals. This work presents the results of a survey evaluating the direct and indirect impacts of the 2020 wildfire season on beef cattle, dairy cattle, sheep, and goat, producers in California, Oregon, and Nevada. Seventy completed surveys were collected between May and July 2021. While dairy producers reported no direct impacts from the fires, beef, sheep, and goat producers were impacted by evacuations and pasture lost to fires. Only beef producers reported losses due to burns and burn-associated deaths or euthanasia. Dairy, beef, sheep, and goat producers observed reduced conception, poor weight gain, and drops in milk production. All but dairy producers also observed pneumonia. Lower birthweights, increased abortion rates, and unexplained deaths were reported in beef cattle, sheep, and goats. This work documents the wide-ranging impacts of wildfires on livestock producers and highlights the need for additional work defining the health impacts of fire and smoke exposure in livestock, as well as the policy changes needed to support producers experiencing direct and indirect losses.

Feasibility of an asynchronous general practitioner-to-general physician eConsultant outpatient substitution program: A Queensland pilot study.

BACKGROUND AND OBJECTIVES: The use of an 'eConsultant' to support the family physician is an established outpatient substitution model in North America. This pilot study investigates the feasibility of the eConsultant model for complex chronic disease management within the Australian setting. METHOD: This pilot study was implemented in one urban and four rural/remote general practices in one state. The general practitioner (GP) sent a request for advice (RFA), a clinical summary with a specific clinical question/s, via secure messaging to a physician working remotely. Responses were required for GP/patient follow-up within 72 hours. RESULTS: The mean (standard deviation [SD]) time for general physician reply was 2.1 (1.2) days, and mean (SD) time from initial to subsequent GP/patient review was 14.8 (16.7) days. Only 13.3% of eConsultations required a subsequent face-to-face outpatient department appointment. DISCUSSION: The eConsultant model is feasible in Australia, with potential for improving access and reducing time to non-GP specialist input.

Evaluating the association between climatic factors and sheep condemnations in the United States using cluster analysis and spatio-temporal modeling.

Sheep in the United States are primarily raised and fed on pasture, making them particularly susceptible to the impacts of climatic factors. This study sought to evaluate the association between climate and whole carcass condemnations in the U.S. as a proxy to evaluate overall sheep health across the U.S. USDA FSIS inspection data was evaluated for whole carcass sheep condemnations between 2005-2016. The analysis focused on condemnations attributed to caseous lymphadenitis, the most frequent cause of sheep condemnations during this period. Data was analyzed on the climate division scale - 344 subdivisions of the contiguous United States that divide states into nearly homogenous climatic regions. Using space-time cluster analysis for high rates of condemnations, ten clusters were identified ranging across the United States. All but one of these clusters was confined to single climate division, with lengths ranging from 1 to 72 months. A zero-inflated Poisson regression found significant associations between condemnation counts and precipitation, cooling degree days (an indicator of higher temperatures), year, and division of the United States. The model had a marginal R-squared of 0.54. This study has identified high risk clusters where higher than expected condemnations are concentrated. The confirmation of an association between climatic factors and condemnation numbers suggests that management practices targeted at protecting pasture-raised small ruminants from weather extremes would improve overall animal health and welfare. Mitigation strategies should be considered as we face increasing frequency of extreme weather events and other environmental fluctuations associated with climate change.

Main Outcomes of a Peer-Led Healthy Lifestyle Intervention for People With Serious Mental Illness in Supportive Housing.

OBJECTIVE: The effectiveness of the Peer-led Group Lifestyle Balance (PGLB) intervention, a 12-month manualized healthy lifestyle intervention delivered by peer specialists, was investigated in a sample of persons with serious mental illness who were overweight or obese and living in supportive housing. METHODS: The authors randomly assigned 314 participants from three supportive housing agencies to PGLB or usual care, with assessments at baseline and 6, 12, and 18 months. Outcomes were clinically significant changes from baseline in weight (≥5% weight loss), cardiorespiratory fitness (CRF; increase of ≥50 meters in the 6-minute walk test), and cardiovascular disease (CVD) risk reduction (clinically significant weight loss or CRF improvement). RESULTS: Most participants were from racial-ethnic minority groups (82%, N=255). The mean±SD baseline weight of this sample was 218.8±54.0 pounds, and the body mass index was 33.7±7.2. Compared with the usual care group, a larger proportion of the PGLB group achieved clinically significant changes in study outcomes at 12 and 18 months, but none of these changes was statistically significant. Outcomes differed by site: two sites reported no significant differences between the two groups, and one reported that PGLB significantly outperformed usual care on clinically significant weight loss at 18 months and CVD risk reduction at 6 and 12 months. CONCLUSIONS: The null findings indicate that PGLB was not superior to usual care in helping participants achieve clinically significant changes in weight, CRF, and CVD risk reduction at 12 and 18 months. Questions remain regarding how PGLB works, for whom, and in which settings.

Network Analysis of Swine Shipments in China: The First Step to Inform Disease Surveillance and Risk Mitigation Strategies.

China's pork industry has been dramatically changing in the last few years. Pork imports are increasing, and small-scale farms are being consolidated into large-scale multi-site facilities. These industry changes increase the need for traceability and science-based decisions around disease monitoring, surveillance, risk mitigation, and outbreak response. This study evaluated the network structure and dynamics of a typical large-scale multi-site swine facility in China, as well as the implications for disease spread using network-based metrics. Forward reachability paths were used to demonstrate the extent of epidemic spread under variable site and temporal disease introductions. Swine movements were found to be seasonal, with more movements at the beginning of the year, and fewer movements of larger pigs later in the year. The network was highly egocentric, with those farms within the evaluated production system demonstrating high connectivity. Those farms which would contribute the highest epidemic potential were identified. Among these, different farms contributed to higher expected epidemic spread at different times of the year. Using these approaches, increased availability of swine movement networks in China could help to identify priority locations for surveillance and risk mitigation for both endemic problems and transboundary diseases such as the recently introduced, and rapidly spreading, African swine fever virus.

Evaluation of Implementation of Massachusetts Sports Concussion Regulations: Results of Focus Groups with Athletic Directors.

In 2018, the Massachusetts Department of Public Health (MDPH) conducted focus groups with athletic directors (ADs) from Massachusetts middle and high schools to assess the implementation of legislated regulations relative to the management of concussion (mild traumatic brain injuries; mTBI) among students engaged in extracurricular sports. Two tape-recorded focus groups were conducted with a facilitator. Lists of themes were synthesized by investigators. Overall, participating ADs expressed that the law and accompanying regulations were necessary and important for protecting student athletes, despite some burdensome aspects of implementation. Emerging themes included support for the law, some implementation problems, impact on workload, and recommendations for improving mandated procedures. ADs assume an important role in the management of middle and high school students' mTBI when given the authority to do so through legislation and regulation. Nonetheless, challenges to the daily application of legislated protocols exist and should continue to be evaluated.

Replens prevents preterm birth by decreasing type I interferon strengthening the cervical epithelial barrier.

PROBLEM: A breakdown of the cervical epithelial barrier has been associated with preterm cervical remodeling. It is unknown if Replens, the vehicle for vaginal progesterone, alters cervical epithelial junctional proteins impacting cervical remodeling and preterm birth. METHOD OF STUDY: E17 CD-1 pregnant mice received an intrauterine injection of saline or lipopolysaccharide (LPS). Effect of intravaginal Replens given on day E16 and on E17 coincident with LPS was tested. A second experiment determined if an antibody to the interferon receptor (IFNaR) blocked the effects of LPS. Mice were killed after six hours, the preterm birth rate was recorded, and the serum and cervices were collected for analysis. Additionally, the epithelial cell barrier was assessed using an in vitro permeability assay. RESULTS: Replens decreased the rate of LPS-induced preterm birth within six hours, from 87.5% to 37.5% (P < .005). LPS + IFNaR antibody decreased the rate of preterm birth or vaginal bleeding compared to LPS + control antibody mice, 43.8% vs 87%, respectively (P < .01). E-Cadherin in the mouse serum was increased by LPS, an effect mitigated by treatment with Replens (P < .0001) or the IFNaR antibody (P < .01). Replens + LPS decreased the expression of IFN-ß (P < .01). The anti-IFNaR, as well as Replens, decreased the expression of MMP13 (P < .05) compared to LPS mice. Replens also prevented the LPS-induced increase in permeability (P < .001). CONCLUSION: Replens prevents preterm birth by decreasing the interferon-induced upregulation of MMP13 and the degradation of the cell adhesion protein E-Cadherin. Further studies are needed to determine if Replens can be useful as treatment for preterm birth.

Block of Granulocyte-Macrophage Colony-Stimulating Factor Prevents Inflammation-Induced Preterm Birth in a Mouse Model for Parturition.

OBJECTIVE: A multitude of factors promotes inflammation in the reproductive tract leading to preterm birth. Macrophages peak in the cervix prior to birth and their numbers are increased by the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF). We hypothesize GM-CSF is produced from multiple sites in the genital tract and is a key mediator in preterm birth. STUDY DESIGN: Ectocervical, endocervical, and amniotic fluid mesenchymal stem cells were treated with lipopolysaccharide (LPS), and the concentration and expression of GM-CSF was measured. Pregnant CD-1 mice on gestational day 17 received LPS and an intravenous injection of either anti-mouse GM-CSF or control antibody. After 6 hours, the preterm birth rate was recorded. RESULTS: Treatment with LPS increased the GM-CSF concentration and messenger RNA expression after 24 hours in all 3 cell lines ( P < .01). Mice treated with LPS and the GM-CSF antibody had a preterm birth rate of 25%, compared to a 66.7% preterm birth rate in controls, within 6 hours ( P < .05, χ2). Treatment with the anti-mouse GM-CSF antibody decreased the concentration of GM-CSF in the mouse serum ( P < .01) but did not alter the number of macrophages or collagen content in the cervix. CONCLUSION: These studies demonstrate that GM-CSF is produced from multiple sites in the genital tract and that treatment with an antibody to GM-CSF prevents preterm birth. Curiously, the anti-mouse GM-CSF antibody did not decrease the number of macrophages in the cervix. Further research is needed to determine whether antibodies to GM-CSF can be utilized as a therapeutic agent to prevent preterm birth.

Older adult fall prevention practices among primary care providers at accountable care organizations: A pilot study.

BACKGROUND: Falls are a serious and common problem among older adults. Low-tech, inexpensive, community-based fall prevention programs have been shown to be both effective and cost effective, however, these programs are not well-integrated into clinical practice. RESEARCH DESIGN: We surveyed primary care providers at a convenience sample of two accountable care organizations in Massachusetts to assess their beliefs, attitudes, knowledge, and practices relative to fall risk assessment and intervention for their older patients. RESULTS: Response rate was 71%. Providers' beliefs about the efficacy of fall risk assessment and intervention were mixed. Eighty-seven percent believed that they could be effective in reducing fall risk among their older adult patients. Ninety-six percent believed that all older adults should be assessed for fall risk; and, 85% believed that this assessment would identify fall risk factors that could be modified. Nonetheless, only 52% believed that they had the expertise to conduct fall risk assessment and only 68% believed that assessing older adult patients for fall risk was the prevailing standard of practice among their peer providers. Although most providers believed it likely that an evidence-based program could reduce fall risk among their patients, only 14% were aware of the Centers for Disease Control and Prevention's fall risk assessment algorithm (STEADI Toolkit), and only 15% were familiar with Matter of Balance, the most widely disseminated community fall risk prevention program in Massachusetts. DISCUSSION: New strategies that more directly target providers are needed to accelerate integration of fall risk assessment and intervention into primary care practice.

Towards a feminist understanding of intersecting violence against women and children in the family.

While intimate partner violence (IPV) against women and violence against children (VAC) have emerged as distinct fields of research and programming, a growing number of studies demonstrate the extent to which these forms of violence overlap in the same households. However, existing knowledge of how and why such co-occurrence takes place is limited, particularly in the Global South. The current study aims to advance empirical and conceptual understanding of intersecting IPV and VAC within families in order to inform potential programming. We explore shared perceptions and experiences of IPV and VAC using qualitative data collected in December 2015 from adults and children in Kampala, Uganda (n = 106). We find that the patriarchal family structure creates an environment that normalizes many forms of violence, simultaneously infantilizing women and reinforcing their subordination (alongside children). Based on participant experiences, we identify four potential patterns that suggest how IPV and VAC not only co-occur, but more profoundly intersect within the family, triggering cycles of emotional and physical abuse: bystander trauma, negative role modeling, protection and further victimization, and displaced aggression. The discussion is situated within a feminist analysis, including careful consideration of maternal violence and an emphasis on the ways in which gender and power dynamics can coalesce and contribute to intra-family violence.

Developing a peer-based healthy lifestyle program for people with serious mental illness in supportive housing.

Overweight and obesity disproportionally impact people with serious mental illness (SMI). Healthy lifestyle interventions can improve the health of people with SMI but may need to be adapted for this population. The aims of this study were: to (1) examine the feasibility and acceptability of delivering the Peer-based Group Lifestyle Balance (PGLB) intervention and (2) describe intervention adaptations for people with SMI in supportive housing. Peer specialists and social workers co-facilitated 12 weekly PGLB sessions for 14 supportive housing clients. We conducted structured interviews and collected qualitative data through field notes and two focus groups. Frequencies and measures of central tendencies were used to describe participant characteristics and PGLB feasibility and acceptability measures. Qualitative data was analyzed using directed content analysis. Participants on average attended 8 of 12 sessions, and reported that services were satisfactory and helpful. Intervention adaptations, ongoing throughout the study, focused on adding peer-specialists as co-facilitators, increasing individualized support and developing strategies to address socioeconomic barriers impacting participants' ability to engage in healthy lifestyle changes. Study findings suggest that participants with SMI in supportive housing perceived PGLB as feasible and acceptable. Expanding the relevance and reach of peer-based healthy lifestyle interventions in community settings serving people with SMI requires careful adaptations to the socioeconomic realities of this population and the complexities of living with co-morbid health and mental health conditions.

Characterizing Factors of Employment Status in Persons With Major Depressive Disorder.

Employment is fundamental to mental health recovery. The aim of this study is to construct a parsimonious profile indicating employment potential of people with major depressive disorder (MDD) to facilitate clinical assessment on employment participation. Data were drawn from Waves 1 (2001-2002) and 2 (2004-2005) of the National Epidemiologic Survey on Alcohol and Related Conditions. We included participants who had MDD at Wave 1 and were interviewed in both waves (N = 2,864). We conducted Classification and Regression Tree (CART) analysis to identify key characterizing factors of Wave 2 employment among 32 Wave 1 risk and protective factors. The results show that 82.1% of those employed at Wave 1 were likely to be employed at Wave 2. Among those unemployed at Wave 1, 51% of those motivated to work, measured by work-seeking behavior in the prior year, were likely to be employed at Wave 2. Among those unemployed and motivated to work, better functional mental health was associated with employment (>25.3 vs. ≤25.3). Results highlight the importance of motivation to work, shown in active work seeking, in facilitating employment despite clinical conditions.

Peer-led healthy lifestyle program in supportive housing: study protocol for a randomized controlled trial.

BACKGROUND: The risk for obesity is twice as high in people with serious mental illness (SMI) compared to the general population. Racial and ethnic minority status contribute additional health risks. The aim of this study is to describe the protocol of a Hybrid Trial Type 1 design that will test the effectiveness and examine the implementation of a peer-led healthy lifestyle intervention in supportive housing agencies serving diverse clients with serious mental illness who are overweight or obese. METHODS: The Hybrid Trial Type 1 design will combine a randomized effectiveness trial with a mixed-methods implementation study. The effectiveness trial will test the health impacts of a peer-led healthy lifestyle intervention versus usual care in supportive housing agencies. The healthy lifestyle intervention is derived from the Group Lifestyle Balanced Program, lasts 12 months, and will be delivered by trained peer specialists. Repeated assessments will be conducted at baseline and at 6, 12, and 18 months post randomization. A mixed-methods (e.g., structured interviews, focus groups, surveys) implementation study will be conducted to examine multi-level implementation factors and processes that can inform the use of the healthy lifestyle intervention in routine practice, using data from agency directors, program managers, staff, and peer specialists before, during, and after the implementation of the effectiveness trial. DISCUSSION: This paper describes the use of a hybrid research design that blends effectiveness trial methodologies and implementation science rarely used when studying the physical health of people with SMI and can serve as a model for integrating implementation science and health disparities research. Rigorously testing effectiveness and exploring the implementation process are both necessary steps to establish the evidence for large-scale delivery of peer-led healthy lifestyle intervention to improve the physical health of racial/ethnic minorities with SMI. TRIAL REGISTRATION: www.clinicaltrials.gov; NCT02175641, registered 24 June 2014.

The p150(Glued) CAP-Gly domain regulates initiation of retrograde transport at synaptic termini.

p150(Glued) is the major subunit of dynactin, a complex that functions with dynein in minus-end-directed microtubule transport. Mutations within the p150(Glued) CAP-Gly microtubule-binding domain cause neurodegenerative diseases through an unclear mechanism. A p150(Glued) motor neuron degenerative disease-associated mutation introduced into the Drosophila Glued locus generates a partial loss-of-function allele (Gl(G38S)) with impaired neurotransmitter release and adult-onset locomotor dysfunction. Disruption of the p150(Glued) CAP-Gly domain in neurons causes a specific disruption of vesicle trafficking at terminal boutons (TBs), the distal-most ends of synapses. Gl(G38S) larvae accumulate endosomes along with dynein and kinesin motor proteins within swollen TBs, and genetic analyses show that kinesin and p150(Glued) function cooperatively at TBs to coordinate transport. Therefore, the p150(Glued) CAP-Gly domain regulates dynein-mediated retrograde transport at synaptic termini, and this function of dynactin is disrupted by a mutation that causes motor neuron disease.

Effect of short-term fasting on bone elongation rates: an analysis of catch-up growth in young male rats.

Bone elongation in the postnatal animal is a result of cellular activity during endochondral ossification. Growth plate chondrocytes undergo a differentiation cascade involving stem cell clonal expansion and cellular enlargement during hypertrophy. Nutritional status has a significant effect on rates of bone growth, and a period of accelerated growth will occur if nutritional stunting of growth in early childhood can be corrected. This study focuses on changes in rates of increase in bone length in a model of catch-up growth in 4-wk-old male rats. Animals fasted for 3 d reached a weight approximately 60% of the control littermates. By 28 d postfasting, fasted animals had regained weight to 95% of control levels. A 3-d fast caused an immediate and profound decrease in rate of growth in the proximal tibial growth plate to only 30% of that of control animals, while stopping growth in the distal tibial growth plate. During the rapid initial rate acceleration of bone elongation, growth rate in both growth plates reached that of the control littermates by 7 d postfasting. The proximal tibial growth plate then maintained rates that were 10-15% higher than control over the rest of the experimental period. By 10 d postfasting, the previously fasted animals were on the same weight/rate trajectory as the control littermates. Changes in elongation rates were reflected by dramatic changes in growth plate morphology in all cellular zones. This is the first study to directly correlate weight recovery during catch-up with growth rate responses at the level of the growth plate.