A study was conducted to evaluate the correlation between selected physico-chemical parameters of water and their effects on growth of Rainbow trout (Oncorhynchus mykiss) in raceway system in the area of Sarab Gerdu, Iran. The samples were collected from twenty raceways (270- day old fish, surface area 55m2 flow rate 150 ls-1 total production 15 T). Physico-chemical parameters were the fluctuat...

For long, ammonia has been branded as a harmful acid pollutant causing irreversible damage to the environment. Unlike other pollutants like nitrogen oxides (NOx) and sulphur oxides (SOx), ammonia causes acidification to the environment in a more complex and indirect way. The sequence of reactions between ammonia and acidic aerosols followed with microorganisms to form acidic HNO3 has been well ...

Nitrogenous excretion by the terrestrial anomuran crab Birgus latro L. was examined. The main excretory product was uric acid, representing 79-5 % of total excretory nitrogen. It was eliminated as white faeces separate from undigested food material and made up 82-6% of excretory faecal nitrogen. The faeces were the principal route of nitrogenous excretion, accounting for 96-2% of total excretio...

Six sheep fitted with ruminal fistulas were used in a repeated measurement design with two 24-d periods to investigate the effect of adding a specific mixture of essential oils (MEO) at 0 (control), 0.8 and 1.6 ml/d on apparent nutrient digestibility, rumen fermentation characteristics, rumen microbial population and blood chemical metabolites. Animals were fed with a 50:50 alfalfa hay: concent...

Nitrogenous waste excretion in resting dogfish occurred largely (>90 %) as urea-nitrogen (urea-N) efflux across the gills, with a very small urea efflux via the kidney. Ammonia excretion, almost entirely at the gills, accounted for less than 3 % of total nitrogen excretion. Given the extremely high blood urea levels (approximately 640 mmol-N l-1) 'retained' for osmoregulation, and blood ammonia...

La/Fe/TiO₂ composite photocatalysts were synthesized by Sol-Gel method and well characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen-physical adsorption, and UV-Vis diffuse reflectance spectra (UV-Vis DRS). It is interesting that the doped catalysts were in anatase phase while the pure TiO₂ was in rutile phase. In addition, the composites possessed bette...

Removal of ammonia nitrogen and nitrate nitrogen by an heterotrophic nitrification-aerobic denitrification strain is an economical and effective method. In this article, a kind of heterotrophic nitrification-aerobic denitrification strain which has aerobic denitrification and heterotrophic nitrification ability was selected, and then was identified as rhodococcus sp. by 16S rRNA sequencing anal...

In 1921 Nash and Benedict (11) advanced the hypothesis that urinary ammonia is formed in the kidney from some precursor in the blood. This conclusion was based upon the observation that the concentration of ammonia was higher in the renal vein than in the renal artery, that the quantity of ammonia in arterial blood was too small to supply the ammonia found in the urine, and that the arterial am...

Emission of nitrogen in the form of ammonia from poultry rearing facilities has been an important topic for the poultry industry because of concerns regarding the effects of ammonia on the environment. Sound scientific data is needed to accurately estimate air emissions from poultry operations. Many factors, such as season of the year, ambient temperature and humidity, bird health, and manageme...

Herbicides that bind specifically to Photosystem II greatly increased ammonia liberation by a heterotrophic cyanobacterium incubated with methionine sulfoximine anaerobically in light. Comparison of cells incubated under argon and nitrogen indicated that about one-half of the liberated ammonia came from endogenous sources, as well as from dinitrogen fixation. Chromatography of cell extracts rev...