The objectives of this study were to investigate the association of body weight (BW) at first calving (BWFC) and maturity rate (MR; BWFC as a percentage of mature BW) with first-lactation 305-d milk yield (FLMY), milk yield (MY) in the 24 mo following first calving (24MMY), herd life, and BW change (BWC) through the first month of lactation in Holstein heifers. We retrieved daily milk production records and daily BW records from AfiFarm (S. A. E. Afikim, Kibbutz Afikim, Israel). The data set included daily records for 1,110 Holstein cows from The Pennsylvania State University (n = 435,002 records) and 1,229 Holstein cows from University of Florida (n = 462,013 records) that calved from 2001 to 2016. Body weight at first calving was defined as mean BW from 5 to 10 d in milk of the first lactation, whereas BWC represented change from BWFC to average BW from 30 to 40 d in milk. Firstlactation 305-d MY and 24MMY were analyzed with a linear model that included effects of farm-year-season of calving, age at calving, and quintiles of BWFC, MR, or BWC. Body weight change was analyzed with the same model to determine associations with BWFC. Survival analysis was performed to estimate the effect of BWFC on survival. Heifers in the top 60% of BWFC had significantly higher FLMY (10,041 to 10,084 kg) than lighter heifers (9,683 to 9,917 kg), but there was wide variation in every quintile, and no relationship of BWFC and FLMY existed within the top 60%. Relationships between BWFC and 24MMY were not significant. Heifers with higher BWFC or MR lost significantly more BW in early lactation. Although BWFC and MR were significant predictors of FLMY, they accounted for <3% of variation in FLMY or 24MMY, suggesting that BWFC and MR are not primary contributors to variation in MY. Compared with the lightest heifers, the heaviest heifers were 49% more likely to be culled at a given time. These data indicated that, among heifers managed similarly, heavier heifers produced more milk in first lactation than lighter heifers but lost more BW, faced a higher risk of being culled, and did not produce more milk in the long term. Based on our data, heifers that reach between 73 and 77% MR at first calving can produce more milk in their first lactation without sacrificing long-term MY and herd life.
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We use county-level data to examine how the COVID-19 pandemic affected the tourism and hospitality sector, which was by far the most impacted of all sectors, focusing on employment and wage changes. Results support our hypothesis that rural counties experienced fewer negative impacts or even benefited from the COVID-19 pandemic in terms of job growth . We present maps showing the pandemic’s effects on leisure and hospitality (L&H) employment across the nation, identifying the communities both hardest hit and least impacted. A linear regression model is developed to explore independent factors that influenced the pandemic’s local impact. Results are robust across different measures of the key variable (rurality), including rural-urban continuum codes, distance from metropolitan areas, and population density. We also consider the impacts of social capital, income, and local economic diversification, among other factors. Our results suggest that remote, less-populated counties were more likely to experience stable employment in the L&H sector relative to pre-pandemic levels, and in some cases even experienced employment growth. JEL Classification: J2, J3, R1
Although, the male labor force participation rate is comparable in China and India, female labor force participation rate remains very low in India. In this paper, we examine the factors responsible for the difference in female labor force participation rate between the two countries by carrying out decomposition exercise at three points of time covering two decades. We find that the differences in female labor force participation rate are not explained by the differences in characteristics across the two countries in each of the three year studied. The differences in returns to these characteristics explain most of the differences in participation rate.
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