by-DR Saroj Kumar Thakur,TVO,Ranchi
India enriched with variety of livestock genetic resources. In fact it is assumed as the one of the hub of animal domestication lay in this area of the world.The large livestock population of India is well adapted to the local environmental conditions.
The diseases affecting buffaloes and cattle populations in India in regular manners through viral causative agents are, Foot-and-mouth disease, Malignant catarrhal fever, Infectious bovine rhinotracheitis / infectious pustular vulvovaginitis, Blue tongue and Bovine viral diarrhoea while the diseases which are caused by bacteria are Bovine brucellosis, Tuberculosis, Paratuberculosis,Haemorrhagic septicaemia and Anthrax. Similarly the parasitic diseases are Trypanosomiasis, Ascaridiosis, Fasciolosis, Babesiosis, Theileriosis,Strongilosis, Coccidiosis, Echinococcosis / hydatidosis, Mange. There are some fungal diseases have also been seenwhich are Mycotoxicosis, Ringworm and Degnala. The disease which is still needso much attention to be differentially diagnosed in the field is Deg-nala(Local name) or Myctoxicosis.
¨Mycotoxin is a toxin produced by a fungus under special conditions of moisture and temperaturethat produce toxic results in another organism. And the resulting condition is known as Mycotoxicosis¨.
Deg-nala Disease and Ringworm is most common complication seen in India in dairy animals caused due to mycotoxins. Different molds produce variety of Mycotoxins which are characterized as secondary metabolites. FAO has stated that every year about 25% crops are affected by mycotoxins and make it harmful to utilize it as eatable safe food. Molds can be found throughout the planet earth so that they can affect crops at any stage to produce mycotoxins while they are in the field, or at harvesting stage even crops are in storage or being processed they can be caught by molds. Dairy animals got caught by them when they consume the affected feed.
As molds produce toxins to cause acute toxicity in animals they can also cause chronic conditions in them as well like secondary infectious conditions and decreased milk production. Usually the responsible fungal agents of mycotoxicosis are Aspergillus niger, Alternaria alternata, Fusarium avenaceum, Mucor heimalis,Fusarium oxysporum, Fusarium fusarioides, Cladosporium cladosporoides,Aspergillus flavus and Penicillium notatum. Generally most concerning molds and mycotoxins are Aspergillus, which produce mostly aflatoxin, Fusarium which produce a large variety of mycotoxins like T-2 toxin, zearalenone, deoxynivalenol while Fumonisin and Penicilliummolds which produce ochratoxin and PR toxin. In addition to this ergot is also an example of several other mycotoxins which are considered as detrimental to cattle and buffalo due to their prevalence in many feedstuffs.
History:————–
During the earlier era of 1930s in present Punjab Province of Pakistan, the health of buffaloes fed with rice straw from adjacent area and territory of Deg River showed the quite different symptoms in dairy buffaloes. The British animal health technician Shirlaw serving there at that time investigated about those symptoms and tried to find the reasons with all those signs and named it as DEGNALA. But he did not got any success to find out the exact reason of that disease.
Root Cause and Epidemiology: —————-
Hokonoharaet al. has reported that the susceptibility of Degnala disease varies in cattle and buffaloes. The disease rate is higher in the buffaloes. The infection gets more severity when other micro-organisms like bacteria attacks on the immunodeficient buffaloes infected with Degnala disease so secondary bacterial infection is also partly responsible for degree of disease in animal. The dark black spots in the Rice straw areconsidered as an indication of growth of fungus in it. According to Maqbool etal. This economically important disease is mostly reported from South Asian region from countries India, Nepal and Pakistan. In these countries the disease is mostly prevalent in rice growing areas.
The signs and symptoms————-
The signs and symptoms seen in buffaloes are lameness, edema, gangrenous ulceration of limbs, hooves, ears or tail that are cold to the touch so that it is also called gangrenous syndrome. Sometimes the muzzle and tip of the tongue become gangrenous; there is emaciation, recumbency and eventually death. Sometimes gangrenous portions of the body drop off; in the case of hooves, bones can bee xposed.
• Disease is caused by toxins produced by mold (fungus) that grows on feed (eg.ground nut cake, maize etc) and stored fodder that is damp. Also known as “Degnala” disease in cattle & buffaloes.
• The toxins can occur in concentrations high enough to cause major losses in health and performance of the animal.
• The economic impact of reduced productivity is many times the impact caused by fatalities. Milk production may drop by more than 15%.
COMMON SYMPTOMS————-
• Gradual loss of appetite and body condition, intermittent diarrhoea may be seen.
• Alopecia, sloughing of extremities like tail and ear.
• Gangrenous lesions on foot.
• High producers may show symptoms first.
• Reduction in feed consumption, reduced fertility, abortions, weight loss, increased occurrence of ketosis, Retention of Placenta (ROP), metritis, mastitis and other dis¬eases due to lowered immunity.
Pathogenesis Factor ————
The cause of symptoms in this disease has been thoroughly studied by this columnist during his Master degree in veterinary medicine. The mycotoxin produced by the metabolism of Fusariam fungus dissolves the collagen and elastin into collagenase and elastinase respectively. As a result in the dependent parts of ear, tail, foot blood supply is obstructed and ultimately tissue die of anoxia. In addition to this toxin severely affects liver, lungs, heart, and kidney.
Treatment and Control———
If possible avoid feeding of desiccated straw
Feed properly dried straw and feed half quantity. Give adequate supplementation of green fodder and tree fodder.
Treat the infected with sodium hydroxide @ 1% for 20kg straw.
If available use pentasulphate @ 60 gm on first day and then @30 gm for next 15 days.
Antidegnala liquid @ 10ml orally for 10 days.
Mineral mixture and lactoline should be given along with straw.
What can be done for future control?
Vet technician and farmers should be trained regarding the prevention.
Priority should be given for such disease.
Let´s hope winter rain won´t come next year. We can´t wait until symptoms to appear on buffaloes, in winter lean period give above mentioned drugs along with straw. If symptoms appear, report as soon as possible.
Rx:—————
Treatment—–
It is mostly seen that in Deg nala disease due to specific and symptomatic treatment of acute cases the lesions heal within a few weeks, but in chronic and older cases the treatment lasts for 1 to 32 months. To detect the exact fungi species, the feed sample should be tested and isolated in the agar or liquid media and it should be especially differentially diagnosed with ergot poisoning by observing increase in body temperature, pulse rate, respiration rate, epidemic hyperthermia and hyper salivation. Lesions should be washed and dressed with nitroglycerine 2 percent ointment. In order to achieve the fast recovery, a therapeutic regimen can consist in oxytetracycline at 20 mg/kg BW in a single intramuscular injection or, better, in oral administration of penta-sulphate at30 g daily for ten days. The best way to control the disease by improving feed quality and by using of hydrated sodium calcium alumosilicate (HSCAS) or other sorbents to bind aflatoxins in the gastrointestinal tract.
PREVENTION—————-
• Avoid feeding dry fodder that is or has been damp and is obviously moldy and also avoid feeding feed ingredients with fungus.
• Provide adequate mineral mixture supplements and green fodder.
• Consult a veterinarian immediately on observing any of the above symptoms.
Avoid feeding moldy straw and feed–prevent aflatoxicosis
Why this Disease is so much Appealing?———-
The basic reason for its importance is its differential diagnosis with other diseases.
1. Local farmer still think that its buffalo having wounds on its mouth and foot is suffering from foot-and-mouth disease. So the specific treatment get delayed.
2. Wounds on the udder lead to mastitis and local farmer starts to treat it with antibiotics and market available drugs.
3. Alopecia reported in animal not treated specifically as a symptom of Deg-nala but treated as other conditions like Ringworm.
4. Availability of spores and mycotoxins in soil, silos,machinery and stores for longer and longer periods of time so that every year outbreak of mycotoxicosis is being reported in crops and animals as well but no proper response is seen by authorities.
5. Lack of availability of labs near by rural areas or disease potent areas. As the most of the livestock specially dairy animals are being based in rural areas and crops being cultivated in countrysides so this disease can be diagnosed by history,signs and symptoms but the confirm diagnosis will be after hematological tests of animal as well as of feed sample to detect mycotoxins in the sample.
R
e
ference:on request