Prenatal heat stress during late gestation exerts longterm effects on growth and productivity of the dairy calf. Further, direct exposure to heat stress during the preweaning period impairs calf thermoregulation and performance. We examined the effects of heat stress abatement during the prenatal period, postnatal period, or both on calf performance. We hypothesized that calves exposed to pre-and postnatal heat stress abatement would perform most optimally in terms of thermoregulation, growth, and health responses when compared with calves that are heat-stressed at any time in the pre-or postnatal periods. Holstein calves born to heat-stressed (HT) or cooled (CL) dams during late gestation (44 ± 5 d; prenatal HT or CL) were exposed to heat stress or cooling postnatally for 56 d (postnatal HT or CL), resulting in 4 treatments: HT-HT, HT-CL, CL-HT, and CL-CL; n = 12/treatment. Calves were administered 4 L of pooled colostrum and after 2 d of age allotted 10 L/d milk replacer and up to 3 kg/d concentrate in automatic feeder group pens (n = 6/pen). Postnatal cooling was achieved by 2 fans (average wind speed 2 m/s). Thermoregulatory responses (respiration rate and heart rate; rectal, body, and skin temperature), feed intake, growth parameters including average daily gain and medication events were recorded, and blood samples were collected weekly. Thermoregulatory responses were lower in postnatal CL calves compared with postnatal HT. In the afternoon, HT-HT calves had the highest respiration rate and rectal temperature, HT-CL calves had the lowest respiration rate, and CL-HT calves had the lowest heart rate compared with the other treatment groups. Prenatal CL calves weighed more at birth and weaning with a tendency for greater average daily gain compared with prenatal HT calves, whereas postnatal CL calves had increased milk replacer and concentrate intake and a tendency for reduced fever, infection, and total medication events relative to postnatal HT. Prenatal HT calves were esophageal tube fed more often than prenatal CL. Blood hematocrit and 24-h serum IgG concentration were greater in prenatal CL calves relative to prenatal HT. Prenatal heat stress abatement improves weight gain, hematocrit, and immunoglobulin transfer, whereas postnatal heat stress abatement modulates thermoregulatory responses, feed intake, and calf health. This study is the first to characterize the combined effects of pre-and postnatal heat stress or active cooling on the dairy calf.

The reuse of gray water for applications ranging from irrigation to showering is a viable means to reduce net water demand when water supplies are stressed. The objective of this study was to investigate the treatment of gray water using biologically active granular-activated carbon (GAC) and

Target specific polymeric micelles loaded with fluorescence dye molecules in their hydrophobic cores were made from block co-polymer of poly(carprolactones) 23 -b-poly(ethylene oxide) 45 (PCL23-b-PEO45). It was found that the micelles are stable against pH changes from 2 to 12 and temperature variation up to 65 °C. The dye molecules can be released to the solution upon exposing the micelles to organic solvents or ultrasound. A rapid and highly sensitive immunoassay based on the above micelles was developed, and the assay can detect specific target proteins in femtomolar range from complex biological samples such as serum mimics and cell lysate. For example, less than 0.15 unit/ml of ovarian cancer specific antigen 125 (CA125), equivalent to 7.5 × 10 -15 M, can be reliably detected in solution. We also demonstrated the assay can detect a cell surface biomarker (SAAE-4) from a single human embryonic stem (hES) cell.

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