Cradle-to-farm gate environmental footprints of beef cattle production in Kansas, Oklahoma, and Texas.

A comprehensive national assessment of the sustainability of beef is being conducted by the U.S. beef industry. The first of 7 regions to be analyzed is Kansas, Oklahoma, and Texas. A survey and visits conducted throughout the region provided data on common production practices. From these data, representative ranch and feedyard operations were defined and simulated for the varying climate and soil conditions throughout the region using the Integrated Farm System Model. These simulations predicted environmental impacts of each operation including cradle-to-farm gate footprints for greenhouse gas emissions, fossil-based energy use, nonprecipitation water use, and reactive N loss. Individual ranch and feedyard operations were linked to form 28 representative production systems. A weighted average of the production systems was used to determine the environmental footprints for the region where weighting factors were developed based on animal numbers reported in the survey and agricultural statistics data. Along with the traditional beef production systems, Holstein steer and cull cow production from the dairy industry in the region were also modeled and included. The carbon footprint of all beef produced was 18.3 ± 1.7 kg CO2 equivalents (CO2e)/kg carcass weight (CW) with the range in individual production systems being 13 to 25 kg CO2e/kg CW. Energy use, water use, and reactive N loss were 51 ± 4.8 MJ/kg CW, 2,470 ± 455 L/kg CW, and 138 ± 12 g N/kg CW, respectively. The major portion of each footprint except water use was associated with the cow-calf phase; most of the nonprecipitation water use was attributed to producing feed for the finishing phase. These data provide a baseline for comparison as new technologies and strategies are developed and implemented to improve the sustainability of cattle production. Production information also will be combined with processing, marketing, and consumer data to complete a comprehensive life cycle assessment of beef.

Serum estrogenicity and biological responses in African catfish raised in wastewater ponds in Ghana.

Reuse of wastewater for aquaculture improves the efficient use of water and promotes sustainability but the potential effects of endocrine disrupting compounds including estrogens in wastewater are an emerging challenge that needs to be addressed. We examined the biological effects of wastewater-borne estrogens on African catfish (Clarias gariepinus) raised in a wastewater stabilization pond (WSP) of a functioning municipal wastewater treatment plant, a wastewater polishing pond (WWP) of a dysfunctional treatment plant, and a reference pond (RP) unimpacted by wastewater, located in Ghana. Measurements of estrogen concentrations in pond water by liquid chromatography/tandem mass spectrometry showed that mean 17 ß-estradiol concentrations were higher in the wastewater ponds (WWP, 6.6 ng/L±2.7 ng/L; WSP, 4.9 ng/L±1.0) than the reference (RP, 3.4±1.1 ng/L). Estrone concentrations were found to be highest in the WSP (7.8 ng/L±1.7) and lowest in the WWP (2.2 ng/L±2.4) with the RP intermediate (4.7±5.0). Fish serum estrogenicity assayed by E-SCREEN was significantly higher in female vs. male catfish in the RP and WSP but not in the WWP (p≤0.05). Histological examination of liver and gonad tissue showed no apparent signs of intersex or pathology in any ponds. The similarities in various measures of body indices between fish of this study and African catfish from freshwater systems suggest that aquaculture may be a suitable reuse option for treated municipal wastewater.