A multidisciplinary approach to assess the welfare of weaned pigs during transport at three space allowances.

Transport can be a stressful experience for pigs, especially in pigs simultaneously experiencing weaning stress. The objective of this study was to use a multidisciplinary approach to assess the welfare of weaned pigs during transport at 3 space allowances. A commercial semitrailer, fitted with compartments, provided 0.05, 0.06, and 0.07 m(2)/pig. The study recorded frequency of standing, lying, sitting, and standing-rearing on another pig during the entire duration of transport. Blood samples, body weights, and lesion scores were collected from a subset of pigs (n = 48 per space allowance) in each experimental compartment. Transport time for the pigs was 148.0 +/- 10.0 min to the wean-to-finishing site. Total white blood cell counts, cortisol, and several blood chemistry values increased (p < .05) after transport regardless of space allowance. Glucose and body weight decreased (p < .05) after transport regardless of space allowance. Space allowance influenced stand-rearing, sitting, standing, and lying behaviors in pigs. Combining behavioral and physiological measures of stress provides a robust picture of piglet welfare during transport at different space allowances.

Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates.

Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, & 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments.

The effects of coal tar based pavement sealer on amphibian development and metamorphosis.

Coal tar based pavement sealers are applied regularly to parking lots and contain significant levels of polycyclic aromatic hydrocarbons (PAHs). Recently a connection between elevated levels of PAHs in streams and storm water runoff from parking lots has been identified. We tested the hypothesis that coal tar based pavement sealers could alter the survival, growth, and development of amphibians using a model species, Xenopus laevis. Ten fertilized individuals were placed singly into containers containing one of four treatment groups: control, low, medium, and high (respective nominal concentrations 0, 3, 30, and 300 ppm TPAH). All of the individuals in the high exposure group died by the sixth day of exposure. By day 14 there were significant patterns of stunted growth (p<0.0001) and slower development (p=0.006) in the medium and high exposure groups relative to the control and low treatment groups. When the experiment ended on day 52 the control and low-dose individuals had achieved more advanced developmental stages than the medium group (p=0.0007). These data indicate that these commonly used coal tar based pavement sealers may potentially affect the amphibian taxa living in areas that receive storm water runoff.