AMMONIA TOXICITY - A SILENT KILLER

AMMONIA TOXICITY - A SILENT KILLER

Ammonia poisoning is one of the largest killers of poultry. It is a gas present in the atmosphere of every poultry house. Ammonia is a product of protein catabolism. It results from the chemical decomposition of uric acid in the droppings by certain bacteria in the litter. It is particularly high in houses where litter is not changed for the use of successive flocks. The main factors affecting atmospheric ammonia concentration in poultry houses are litter conditions and air movements (ventilation). Moisture content, pH and the temperature of the litter, influence the degradation of uric acid by bacteria. Poor ventilation, loose droppings and faulty, over filled or low positioned drinkers, are common causes of wet litter in poultry houses. At room temperature, ammonia (NH3) is a highly water-soluble, colorless, irritant gas with a unique pungent odor. People can generally smell ammonia at concentrations between 20 and 30 ppm. The most common mechanism by which ammonia gas causes damage occurs when anhydrous ammonia (liquid or gas) reacts with tissue water to form the strongly alkaline solution, ammonium hydroxide. In the case of ammonium hydroxide, the tissue breakdown, liberates water, thus perpetuating the conversion of ammonia to ammonium hydroxide.

NH3 + H2O→ NH4 OH

Ammonium hydroxide can cause severe alkaline chemical burns to skin, eyes, and especially the respiratory system. High continuous exposure causes ulceration of cornea, opacity which leads to the blindness due to which birds can not eat the feed. Mild exposures primarily affect the upper respiratory tract. The gastrointestinal tract also may be affected if ammonia is ingested. In the respiratory tract, this results in the destruction of cilia and the mucosal barrier to infection. Furthermore, secretions, sloughed epithelium, cellular debris, edema, and reactive smooth muscle contraction cause significant airway obstruction. As a result opportunistic Mycoplasma with the help of E. coli cause complex respiratory disease (C.R.D). In this case antibodies titer can not be formed properly. As a result Chances of N.D. increases. In case of N.D this disease is called choronic complex respiratory disease (C.C.R.D). Ammonia toxicity also cause cirrhosis of liver, due to which imbalance of osmolarity and osmotic pressure occur which lead to Ascities.

Treatment and Control: We can control ammonia concentration in the farm by ammonia sensors and with proper ventilation according to the environment. Wet litter should be removed from the shed. There is no blood supply in air sacs so no antibiotic can cause damage to the Mycoplasma. But we can use Macrolide group, because they absorb and come in secretions and cause inactivation of secondary bacteria. If N.D come in the neighbor farm and in our farm ammonia problem is present then do the spray of N.D.V. which causes the local immunization.

 By Dr. Rauf Aslam (D.V.M,Mphil scholar)

 raufaslam@hotmail.com