Characterization of Pseudomonas aeruginosa isolates associated with mortality in broiler chicks.

In mid-2000, a broiler chicken company in Alabama experienced high early mortality rates in chicks from two different hatcheries. Five isolates of Pseudomonas aeruginosa, obtained from these contaminated hatcheries and resulting broiler chicks with omphalitis, were selected to determine virulence of the bacteria. One-day-old specific-pathogen-free white leghorn chicks were placed into positive pressure isolation units (10 chicks per unit); feed and water were provided ad libitum.

The effect of adding copper and various fat sources to the diets of weanling swine on growth performance and serum fatty acid profiles.

An experiment involving 540 weanling pigs was conducted to determine the effect of the addition of Cu (5, 125, or 250 ppm) on the growth performance and serum fatty acid profiles of pigs fed diets that contained no added fat (NO FAT), 5% added soybean oil (SBO), 5% added animal fat (ANI), or 5% added medium-chain triglycerides (MCT). Pigs had ad libitum access to corn-soybean meal-based diets that contained 10% whey and 5% fish meal during the 28-d trial. Pigs were weighed and pen feed intakes were recorded weekly.

Enumeration of Autotrophic Ammonium-oxidizing Bacteria in Marine Waters by a Direct Method.

A membrane filter method was developed for enumerating, in mixed populations, autotrophic nitrifying bacteria which transform ammonium to nitrite. It gave counts in good agreement with estimates obtained by using a most-probable-number procedure. Compared to the most-probable-number procedure, the membrane method is convenient and precise.

Utilization of Inorganic Nitrogen Compounds by Sphaerotilus natans Growing in a Continuous-Flow Apparatus.

Sphaerotilus natans was grown, attached, in a continuous-flow apparatus with inorganic nitrogen compounds (NH(4)Cl, NaNO(2), or NaNO(3)) as the only sources of nitrogen. The growth rate with NH(4)-containing medium did not differ from that with media containing glutamate or Casitone as the nitrogen source.